Research news 2010

N I F E S e x a m i n e s t h e s e a f o o d y o u e a tRESEARCH NEWS

2010

Dear reader,

Norway is one of the world's largest seafoodnations, and the fisheries and aquacultureindustry is responsible for a considerablefood production, both in a national andinternational context. In this respect Norwayhas an important responsibility to documentthat the seafood in different markets, both inNorway and abroad, is safe and healthy. Atthe same time, it gives a unique opportunityto acquire the knowledge necessary to securethe future framework for one of Norway’smost important industries. In this innovativedevelopment, NIFES research will beessential.

The Health Directorate's report from 2009which deals with the trends in the Norwegiandiet says that we eat less fish than we should.If we alter the diet to include more fish andless of the foods that contain saturated fat,this will together with exercise help us toprevent lifestyle diseases such as obesity,heart attacks and diabetes 2. Until now, thehealth effects of eating fish have mainly beenassociated with marine omega-3 fatty acids,

however, there are many otherbeneficial components in seafood.For example, it seems that fishproteins may have an ability to limitthe development of obesity. This isan example of the kind of researchwe are carrying out here at NIFES. Inaddition to examine how seafoodaffects the health of the consumer weexamine the effects of environmentalpollutants on seafood safety and thecomposition of future feeds forfarmed fish.

The Institute conducts several surveillanceprogrammes in order to examine the contentsof various undesirable substances in fish feedand seafood, such as environmentalpollutants. Results from surveillanceprogrammes in 2009 showed that levels ofenvironmental pollutants in seafood aregenerally low. Research results suggest thatcertain nutrients in seafood such as seleniumand omega-3 fatty acids may counteract theeffects of certain pollutants. These effects arevery interesting and will be investigatedfurther. Research at the Institute has also

shown that cod larvae feed should have adifferent nutritional composition than thefeed used today for an optimal developmentof cod fry in aquaculture.

In this booklet you will find a summary ofthe NIFES`s activity in 2009, and we hopethat you will find the information bothinteresting and useful!

Enjoy.

Øyvind Lie

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Research News from NIFES

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ContentsSustainable development of fish farming 7

Alternative feed raw materials 7

- Genetically modified plants, fish healthand consumer health 7

- What is the effect of plant raw materials infeed for full-scale production? 8

- Do plant oils increase the risk of bone deformities? 9- Plant raw materials do not increase the

incidence of cataracts among salmon 10

Fish farming of other species 12

- The correct composition of nutrientsfor farmed cod 12

Climate and fish nutrition 15

- What are the consequences of climate changesfor feeding of farmed salmon? 15

Fish nutrition and the development of disease 16

- Too little phosphorus in the feed and lightmanipulation affects bone formation 16

- The heart disease ”cardiomyopathic syndrome ”(CMS) in salmon 16

- Fish in research studies – well being and environment 17

Regulations for safe feeds and seafood 19

- Upper limits for endosulfan in fish feed 19- Purified fish oil in the feed has no

negative effect on fish health 20- Exposure to toxaphene through the feed 21- Synthetic antioxidants in feed – their

significance for food safety 22

Undesirable substances in Norwegianseafood– status 25

- Baseline of undesirable substances inmajor fish species 25

- Continuing the Barents Sea management plan 30- Management plans for the Norwegian Sea

and the North Sea 30- Long-term surveillance 31- Unique monitoring of parasites in pelagic fish 31

Environmental status of seafoodin Bergen’s City Fjord 32

- Generally low levels of environmental pollutantsin various species of cod fish and blue mussel 32

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Surveillance in proximity to shipwrecks 36

- Monitoring by the submarine wreckU864 off Fedje 36

- Analysis of seafood taken aroundMS Welheim 39

- Evaluation of food safety after oil spills 39

Surveillance for the Norwegian Food Safety Authority 41

- Status report on the levels of undesirablesubstances and drug residues in farmed fish 41

- Marine oils for human consumption 42- Low level of undesirable substances in

mackerel from Grenland Fjord area 43- Low level of undesirable substances in

Svolvær paste 43- High dioxin level in eel from the

Grenland Fjord area 43- Low level of undesirable substances and

varying microbiological quality in sushi 44

Monitoring of shellfish 46

- Mainly good microbiological quality of shellfish 46- Low level of undesirable substances in shellfish 48- Grading oyster quality 48

Environment and effect on seafood safety 50

- How are cod in a seawater inlet in Bergenaffected by environmental pollutants? 50

- Does oil recovery affect the reproductivepattern of the cod? 52

- Combination effects of environmentalpollutants in salmon 52

Interactions between environmentalpollutants and nutrients 55

- Is mercury toxicity affected by nutrientsin the fish? 55

- Zebra fish 55- Interactions between nutrients in

salmon and PCB 57- Salmon silage is a possible source of

bioactive components 57- Do plant oils in feed affect intake of

mercury by salmon? 58- The marine omega-3 fatty acid EPA

protects cells against mercury 58

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Can seafood provide protectionagainst lifestyle diseases? 61

Obesity and diabetes 62

- Fat combined with sugar or starch playsa role in the development of obesity 62

- Do mice get fatter from a yo-yo diet? 63- Proteins from marine sources and

insulin resistance 64

Mental health 64

- Can seafood help for postnatal depression? 64

Cardiovascular diseases 65

- Eating salmon reduces the risk ofcardiovascular disease 65

Back and joint pains 66

- Do marine oils help against back pains? 66- Whale and seal oil alleviate joint pains 67- Oxidised omega-3 products – do they

affect our health? 68

Bone health 68

- Vitamin D in fish fillet – what is itssignificance for bone health? 68

Aquamax 70

NORAD cooperation project 73

Method development – undesirablesubstances and nutrients 75

- NIFES: A national reference laboratory 75- Renewed accreditation status for NIFES 75- Method activity 76

Aquaculture Nutrition 78

”Fiskesprell” 78

Teaching and education 79

Teaching for the University of Bergen 79

Innhold

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Forecasts show that in 2030 theglobal production of seafood fromthe aquaculture industry will becomparable to the production fromthe traditional fishing industry. Thelimited supply of marine feed rawmaterials will therefore be aconsiderable challenge. At present,commercial fish feed may containup to 50% vegetable oils and 50%vegetable proteins, as analternative to marine raw materials.Alternative feed raw materials

include plant oils, plant meal, gene-modified plant raw materials andkrill meal. A prerequisite for majorchanges in feed composition, suchas a high proportion of plant rawmaterials, is an understanding ofthe right balance of nutrients thatneed to be in the new feed, inorder to maintain fish health andwellbeing and facilitatesustainable development of the fishfarming industry.

Alternative feed rawmaterials

Genetically modified plants,fish health and consumerhealth

Soy and maize are used as alternative plant-based raw materials in fish feed. Since alarge proportion of these and other plant rawmaterials are genetically modified (GM), it isimportant to establish whether the GM-modifications in feed affect the fish. NIFEShas previously carried out a number offeeding trials to examine the effects of GMraw materials on salmon health. Fish healthstatus has been established by using a set ofcommon indicators that can reveal alterationsof fish health. NIFES has so far seen onlyvery small differences in the health of salmonthat have been given GM soy of the Roundup Ready (RRS) type and those that havebeen fed unmodified soy. As a feedingredient, RRS appears to be just as safe asunmodified soy.

Sustainable development of fish farming

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“A prerequisite for major changes in feedcomposition, such as a high proportion ofplant raw materials, is an understanding ofthe right balance of nutrients that need to bein the new feed”

GM maize and fish healthSince the genetic changes are unique for eachGM plant type, the effects of each type mustbe considered individually. NIFES hastherefore carried out a study to determinewhether salmon health is affected when thefeed contains GM maize of the MON810type. The results will be available in 2010.

Is consumer health affected bysalmon fed a feed containingGM maize?Following up research carried out todetermine whether salmon health is affectedby GM maize in the feed, NIFES is carryingout trials to determine whether eating suchsalmon affects the health of the consumer.Rats are used as a model in these studies.

In collaboration with: Norwegian Schoolof Veterinary Science, National VeterinaryInstitute and Aquaculture Protein Centre.Funding: Research Council of Norway andMinistry of Fisheries and Coastal Affairs.

What is the effect of plantraw materials in feed forfull-scale production?

The results from small-scale feeding trialscannot without further ado be transferred tolarge-scale salmon production, partly becausethe production and environmental conditionsin a large production unit can vary greatly.Alternative feed raw materials for salmonhave been a key topic at the Centre forAquaculture Competence (CAC) from 2007to 2009. CAC is a commercially run R&Dcentre which carries out fish farming

research based on full-scale production.

NIFES has provided knowledge accumulatedfrom previous feed trials, and participated inthe planning and design of a full-scale studyof plant-based raw materials. The purposewas to determine whether the effects ongrowth, fish health and product quality foundin full-scale feed trials were the same asthose found in smallscale trials. A further aimwas to document food safety in full-scaleproduction. Fish oil in feed may containpersistent organic pollutants (POPs).Preliminary results from the full-scale studyshow that when 64% of the oil in the feed

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What is a gene-modified plant product?A genetically modified plant product has had its genetic properties changed by using genetechnology. Gene technology makes it possible to reorganize genetic material (DNA) in newways and to transfer DNA between organisms. Through gene modification, an organism canbe given additional genes, genes can be changed, or individual genes can be removed inpart or completely. For example, the soy plant GTS 40-3-2 (Roundup Ready® soy (RRS))contains additional genes which together make the plant resistant to a special type ofpesticide. In the same way, maize variants of the Bt type, such as Mon810, have been maderesistant to certain types of insects through the addition of a gene from the bacterium Bacillusthuringiensis (Bt).

was replaced by plant oil the level of POPsin the salmon was below the level found insalmon that were given a feed where theprotein and the oil content is marine-based.

Heavy metals may accumulate in fish andother seafood, and here fish meal in the feedis a potential source. It was shown that therewere small differences in the levels of heavymetals in both the feed and the salmon when74.5% - 80% of the marine protein sourcewas replaced by plant proteins.

The growth rate was however somewhatlower in the highest plant protein group. It

was no feed related effect on fish health andwelfare, except for moderate intestinalpathological changes observed in all groups.

The data from this trial confirm thatknowledge acquired from small-scale feedtrials on food safety, product quality and fishhealth are transferable to large-scale, usingthese feed ingredients.

In collaboration with: Marine Harvest,Skretting and Akva Group, NationalVeterinary Institute and Institute of MarineResearch.Funding: Marine Harvest, Skretting, AkvaGroup og Ministry of Fisheries and CoastalAffairs

Do plant oils increase therisk of bone deformities?

Farmed salmon can develop bone deformitiesin the spine. This is a recurring problem inthe fish farming industry which givesgrounds for concern with respect to the

wellbeing of fish. The causes of bonedeformities are complex, but access tonecessary nutrients appears to be animportant factor.

In the last few years a steadily increasingproportion of plant oil and plant meal hasbeen used in fish feed. NIFES has carried outfeeding trials in order to determine whetherusing plant oil in feed makes the salmonmore predisposed to inflammatory conditionsin the bone, and whether this in turn leads tobone deformities. The results showed thatthat plant oils in the feed do not increase therisk of salmon developing inflammation-related bone deformities.

In collaboration with: Institute of MarineResearch.Funding: Research Council of Norway.

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What are POPs?Persistent organic pollutants (POPs) areundesirable substances which accumulatein the food chain in the marineenvironment. They are lipid-solublesubstances which therefore re-appear infish oil, which in turn is also used in theproduction of fish feed.

Plant raw materials do notincrease the incidence ofcataracts among salmon

Farmed salmon are predisposed to thedevelopment of cataracts of the eye, whichcan lead to blindness, reduced feed intakeand other consequential conditions. Previousresearch at NIFES has shown a link betweenusing plant oil in the feed and thedevelopment of cataracts among salmonfarmed in net pens.

Fish oil versus plant oilOsmotic stress is one of several causes ofcataracts. In 2009 NIFES studied thedevelopment of cataracts in a culture of eyelenses. The lenses were taken from salmonfed on a feed where the oil content consistedsolely of either plant oils or fish oils. Thesalmon in both groups were equallysusceptible to the development of cataractsdue to osmotic stress. This was despite thefact that some markers indicated an increasedrisk of cataracts when the salmon had been

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given feed containing plant oils and wherethe environmental conditions wereunfavourable.

The fat source of the feed affects thecomposition of fatty acids in the cellmembranes in the organs of the fish. This inturn may be of significance for thedevelopment of cataracts. When the salmonhad consumed feed containing plant oils, thechanges in the composition of fatty acids inthe eye cell membrane were small, comparedwith the eyes from salmon whose feed hadcontained fish oil.

Is histidine an antioxidant?Previous trials have shown that when theamino acid histidine is added to the feed itcan prevent the development of cataracts insalmon. An experiment where the salmon eyelens was studied in culture showed thathistidine may play a role as an antioxidant.Histidine can therefore protect the lensagainst osmotic stress.

These results show that salmon fed a dietcontaining plant raw materials are not moresusceptible to cataracts than salmon given afeed containing marine raw materials.

In collaboration with: Marine Harvest,Institute of Marine Research et al.Funding: Research Council of Norway andMinistry of Fisheries and Coastal Affairs.

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What are antioxidants?Antioxidants are used as preservatives infeeds, food and cosmetics. There are manydifferent types of antioxidants both naturaland synthetic, the best known naturalantioxidant is probably vitamin C.Antioxidants are present in all livingorganisms and they protect cells fromoxidative damage. Synthetic antioxidantsare classified as additives and havetraditionally been divided into two groups,one which maintains colour, and onewhich protects against rancidity.

Osmotic stressOsmosis is the movement of water andother fluids through a semi-permeablemembrane. If the membrane does notrelease particles through, for example salt,the water will flow towards the highest saltconcentration to balance out theconcentrations. If the membrane is a cellmembrane, this can cause osmotic stress inthe cell, because too much water will flowout of or into the cell.

“These results show thatsalmon fed a dietcontaining plant rawmaterials are not moresusceptible to cataractsthan salmon given a feedcontaining marine rawmaterials”

Fish farmingof other speciesA correct nutritional composition of feed iscrucial for a normal development of farmedfish, fish health and seafood safety. NIFEScarries out research to determine the fish’srequirements for the various nutrients andwhat effects these and other substances haveon fish health, wellbeing and development.NIFES has been particularly focused onalternative feed raw materials includinggenetically modified plants. The Institute’sactivities also include the role of correctnutrition in ensuring the predictable and

sustainable production of healthy larvaeprevents deformities, and the debilitation ofbrood stock. In this connection, it isespecially important to understand how thedifferent nutrients in the feed affect eachother, and what consequences this has forfish health.

The correct composition ofnutrients for farmed cod

The correct composition of nutrients isimportant if cod larvae are to grow anddevelop normally, without developingconditions such as bone deformities. NIFEScarries out research to determine how

variations in the composition of nutrients inthe feed for young fish affect growth anddevelopment.

MineralsUnlike salmon larvae, the gastro-intestinaltract of cod larvae is not sufficientlydeveloped to allow digestion of dry feed. Innature, cod larvae eat copepods, which aredifficult to cultivate in a laboratory. Inintensive fish farming the larvae thereforedepend on receiving a supply of rotifers,which are another type of live feed. Rotiferscontain lower levels of minerals thancopepods.

NIFES has carried out a number of feedingtrials where cod larvae have been givenrotifers enriched with one or more minerals.The results indicate that the level of seleniumshould be increased in live feed for codlarvae. It may also be beneficial to increasethe level of iodine. With respect to the otherminerals, we need more knowledge in orderto make any recommendations.

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“NIFES carries out research to determine the fish’srequirements for the various nutrients and what effectsthese and other substances have on fish health, wellbeingand development”

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Fat and fat digestionIt is known that marine fish larvae do notdigest proteins and fats very well. This mayaffect both fish health and growth. NIFEShas therefore carried out research todetermine how much fat cod is able todigest. The results show that codlarvae are able to utilise fatwell 40 days afterhatching.

NIFES has also examinedwhether partly digested fatcan be better utilised by thelarvae. When partly digested fat wasgiven to the larvae before they were weanedonto dry feed, it turned out to be toxic forcod larvae. This kind of fat should thereforenot be added to larvae feed. This is especiallyimportant if fat that has been exposed tohydrolysis treatment is to be used in dry feed.NIFES now plans to compose an optimally

enriched diet for cod larvae based on theaccumulated knowledge of the cod larva’smineral, fat and protein requirement. The diet

will be tested in a full-scale feed trial. TheInstitute will also be carrying out research todetermine how important the iodine level inthe feed is for the growth and developmentof cod larvae.

Bone developmentNIFES is currently

working toestablishmethodologythat can be

used to identifythe mechanisms

involved in the cod’s bonedevelopment, affected by various nutrients.These tools will then be used to determinehow access to different nutrients in the feed,such as fatty acids and vitamin A, inhibit orpromote bone formation at cellular level. Todate, NIFES has characterised some of thegenes that are necessary for bone formationand development.In order to determine the role played by thesegenes in bone development, and how they areaffected by nutrients in the feed, NIFES is

going to set up a bone cell line in thelaboratory (a cell line consists of cells thatare cultured over several generations).

In collaboration with: University ofBergen, Institute of Marine Research, Alltechand Sagafjord Seafarm AS, RadboudUniversity in Nijmegen, University of theAlgarve and Genofisk.Funding: Research Council of Norway’sOutstanding Young Researcher scheme forgene researchers, EU’s 7th FrameworkProgramme, Research Council of Norwayand Ministry of Fisheries and CoastalAffairs.

Climate and fishnutrition

What are the consequencesof climate changes forfeeding of farmed salmon?

Climate changes can lead to changes in thetemperature and pH value of the sea.Forecasts show that the sea temperature isrising along the Norwegian coast. This couldhave consequences for salmon which thrivewhen the temperature is below 17°C. NIFESis engaged in research to determine howchanges in the sea temperature affect thesalmon’s ability to utilise nutrients in thefeed.

Reduced feed intakeFeeding trials conducted at temperatures inthe range 13 − 19°C show that salmon eatless and the feed intake is reduced when thewater temperature rises. The trials werecarried out in tanks on land where it was

possible to keep the temperature stablethroughout the entire trial period. At higherwater temperatures the salmon grew moreslowly and they were less physically activewhen the temperature increased. This maypartly explain the decline in the feed factorand the feed intake. The fat level of the feedwas also important with respect to how muchfeed the salmon consumed. The feeding trialsalso revealed that key genes are controlled bythe environmental temperature. This is anarea that requires more research.

Vitamin E level in the feed may helpAn optimal composition of nutrients in thefeed is important for the wellbeing and goodhealth of the salmon. Vitamin E is anantioxidant which stops the cells in the fishorgans from breaking down, partly byprotecting the fatty acids in the cells againstoxidation (oxidative stress). In higher watertemperatures the salmon experiences a higherlevel of oxidative stress.

The results from the controlled feed trials

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Feed factorThe factor describes how much dry food that is necessary to produce one kilogram of farmedAtlantic salmon.

Feed intakeDescribes the amount of feed the fish eats.

What is oxidative stress?Cells create free radicals in their metabolism. These are neutralized by antioxidants. If morefree radicals are created than can be neutralized by the body, oxidative stress occurs.Oxidative stress may affect many of the normal processes in a cell. A stress response ischaracterized by biochemical and physiological changes in the cell, such as the production ofdifferent proteins, due to an external influence.

show clearly that the salmon’s vitamin Estores were tapped when the temperaturerose. A full-scale feeding trial was thereforecarried out where the salmon in the tankswere given a feed enriched with vitamin E.The temperature decreased with the depth ofthe water, and at its deepest it was 16°C.Salmon which had been given a feedcontaining high levels of vitamin E were lesspredisposed to oxidative stress than salmonwhich had been given a feed with low levelsof vitamin E. High levels of vitamin E in thefeed had a positive effect on the final qualityof the fillet and also prolonged the product´sshelf-life, as well as improving the colour.

These results will contribute to the process ofestablishing a feed composition whichensures that the fish thrives and grows and isbetter able to utilise the feed at high seatemperatures. This knowledge will beimportant for the future good health of thesalmon.In collaboration with: Institute of MarineResearch, Marine Harvest Norway, NofimaMarin and Skretting.Funding: Research Council of Norway.

Fish nutrition and thedevelopment of disease

Too little phosphorus in thefeed and light manipulationaffects bone formation

The bone in salmon is built up of structuralproteins and minerals (mainly calcium andphosphorus).

In fish farming it is customary to addphosphorus to maximise growth and ensureproper sone mineralisation. At the same time,every effort is made to keep the phosphorusconcentration as low as possible asphosphorus in the fish faeces and feed wastehas negative environmental effects .

In fish farming, one of the uses of lightmanipulation is to control sexual maturationand stimulate growth. In collaboration withthe Institute of Marine Research, NIFES hascarried out feeding trials which show that thevitamin D system in salmon is affected by

low phosphorus levels in the feed andexposure to continuous light. (The vitamin Dsystem: How vitamin D and phosphorusregulate the uptake of these nutrients fromthe intestine and how it also regulates bonemineralisation.)

This led to changes in bone development inthe salmon, which can result in bonedeformities. NIFES will continue to workwith development of bone deformities andthe level of phosphorus in salmon feed.

In collaboration with: Institute of MarineResearch.Funding: Research Council of Norway.

The heart disease”cardiomyopathicsyndrome” (CMS) in salmon

The make-up of nutrients in the feed isimportant for the health of farmed fish. Theheart disease CMS leads to fish mortality andis an increasing problem among adultsalmon. A large research programme,

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involving many researchers andrepresentatives from the commercial sector,is now focusing on CMS. The project willinclude both experimental infection trials andfield studies.A model established previously shows thatCMS is an infectious disease, but the factorswhich give rise to a predisposition toinfection, and the cause of the disease are asyet unknown. NIFES will contribute byidentifying the development of the disease inthe cardiac muscle as well as the role playedby nutrition, by developing possiblephysiological and nutrition-related markersof the disease. Analytical work has startedand the results are expected by the end of2010.In collaboration with: Marine Harvest,Norwegian Veterinary Institute, NorwegianSchool of Veterinary Science, NofimaMarin, Pharmaq, AquaGen, Lerøy SeafoodGroup and Skretting/Ewos.Funding: Research Council of Norway,Fishery and Aquaculture Industry ResearchFund and Ministry of Fisheries and CoastalAffairs.

Fish in research studies –well being and environment

More than 90% of the animals used inresearch studies in Norway are fish, and theyare used in applied, biomedical and basicresearch. Where research is carried out usinganimals, there is a requirement to ensure thatthe animals’ wellbeing is protected inaccordance with the Animal Protection Actand Regulations relating to researchinvolving animals. Different species, such assalmon, halibut, cod and zebrafish havecompletely different environmentalrequirements and, consequently, may alsohave different needs in order to ensurewellbeing. At the same time, it should bepossible to measure and recogniseappropriate wellbeing, in order to ensure thatthis is implemented in fish trials.

On behalf of the Research Council ofNorway, researchers from several researchinstitutes have written a report called ” Fishin research – environmental requirements andindicators of wellbeing among fish”, whichdeals with research requirements in the areaof animal wellbeing with respect to fish inresearch studies available atwww.forskningsradet.no. The aim of thereport is to contribute to rising the quality ofresearch results through better use of fewerfish in trials. A researcher from NIFES hasheaded this work.

In collaboration with: Norecopa,Norwegian Institute for Nature Research,Institute of Marine Research, Nofima Marin,Bergen University College and Veso Vikan.Funding: Research Council of Norway.

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“More than 90% of the animals used in researchstudies in Norway are fish, and they are used inapplied, biomedical and basic research”

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Regulations for safe feed and seafood

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Internationally and nationally thereis an increasing focus on foodsafety and an increasing number oflegislation exist for undesirablesubstances in both feed and food.Scientifically based knowledge ofenvironmental pollutants in seafoodand their effects is a prerequisite forestablishing legislation Undesirablesubstances found in feeds can betransferred to edible parts of thefish and affect food safety. Hence,knowledge regarding thesesubstances is important to enablethe authorities to give dietaryadvice about seafood to the public.

An understanding of the effects,and transfer of undesirablesubstances from the feed to the filletis an important scientific basis forrisk assessments conductednationally by the NorwegianScientific Committee for FoodSafety and the European FoodSafety Authority (EFSA) in the EU.Risk assessments form the scientificbasis for risk managementdecisions such as establishing EUmaximum limits for contaminants infeed and food, which are primarilyset by the European Commission.

Upper limits for endosulfanin fish feed

The increasing use of plant raw materialsrather than marine ingredients in fish feedcan result in higher levels of the insecticideendosulfan in fish feed. Endosulfan is anorganic chloride pesticide which is banned inNorway but is still used in agriculture insome parts of the world. It can affect thehormone balance in humans and mammals,and the effect can be is reinforced when itoccurs along with other chlorine pesticides.

Fish, and particularly salmon are vulnerableto water- borne endosulfan, but there islimited knowledge regarding the effect ofdiet-borne endosulfan exposure in salmon.The EU’s upper limit for endosulfan in fishfeed is based on its toxicity via exposure towater, and not on exposure through the feed.The upper limit for endosulfan in fish feed(5 μg per kg of feed) is therefore much lowerthan the upper limit for endosulfan in feedfor other animals (100 μg per kg of feed).

This restricts the use of plant raw materialsin feed for fish.

In order to study the toxicity and transfer ofendosulfan from feed to fish, researchers atNIFES have carried out a feeding trial withsalmon which were fed a diet containing oneof three different levels of endosulfan. Groupone was given a feed with 5 μg of endosulfanper kg of feed (the current upper limit forfish feed), group two received 50 μg ofendosulfan per kg of feed, while group threewas given 100 μg of endosulfan per kg offeed (the current upper limit in feed forspecies other than fish). No effects werefound on growth, the ability to digestnutrients, blood health parameters or changesin cells taken from the fish organs in any ofthe groups.

In another study on cultured salmon livercells , the results showed that thecomposition of fatty acids in the liver cellsfrom salmon which had been given feedcontaining plant oils differed from thefindings from salmon which had been givenfeed containing fish oils. However, the

overall conclusion was that the source of theoil in the feed had little significance for theway the liver cells responded to endosulfan.The studies described above along with the

results from three previous studies carriedout by researchers at NIFES on the effect ofendosulfan on fish wellbeing will form thescientific basis of part of the re-evaluation ofthe limit for endosulfan in fish feed by theEU Commission.

In collaboration with: Ewos-Innovation,Skretting ARC, Biomar.Funding: Fishery and Aquaculture IndustryResearch Fund and Ministry of Fisheries andCoastal Affairs.

Purified fish oil in the feedhas no negative effect onfish health

Persistent organic pollutants (POPs) arepredominantly man-made, undesirablesubstances which accumulate in the foodchain. They are fat-soluble substances whichare present in fish oil, which in turn is used

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in the production of fish feed. In order toeliminate them from the feed, fish oil can berefined. The purification process removes notonly undesirable substances, but also the fat-soluble vitamins A, D, E and K. Consequentlyfat soluble vitamins are supplemented to fishoil. The purification process affects the smelland consistency of the oil. It is also possiblethat the process removes other componentswhich are important for the fish, in addition tonutrients.

NIFES has examined the effect that purifiedoil in the feed has on fish health and nutrients,and on the composition of undesirablesubstances in the fillet. A feeding trial hasbeen carried out where salmon with a startingweight of 80 grams were given a feedcontaining refined or unrefined fish oil. Thetrial continued until the salmon had a marketweight of 5 kg.

The composition of this feed was otherwisethe same as the feed used on the market today,apart from the fact that the fish oil wasrefined. The levels of undesirable substancesand vitamins in the muscle and liver where

measured throughout the entire period, alsopaying attention to bone development,cataracts, skin injuries, taste and colour. Theresults show that, fish growth and health wereequally good when refined fish oil was usedwith the addition of synthetic fat-solublevitamins in the feed. The level of undesirablesubstances in salmon given a feed containingrefined oil is comparable to the concentrationfound in lean fish such as cod or beef.

In collaboration with: Skretting ARC, EwosInnovation, Biomar, Polar Feed, GIFAS,Norwegian Fishermen’s` Sales Organisationfor Pelagic Fish.Funding: Fishery and Aquaculture IndustryResearch Fund, Research Council ofNorway, Fishery and Aquaculture IndustryResearch Fund , Ministry of Fisheries andCoastal Affairs, GIFAS, NorwegianFishermen’s` Sales Organisation for PelagicFish.

Exposure to toxaphenethrough the feed

Toxaphene is a pesticide which is found in fishoil used in feeds. Most of the studies on thetoxicity and metabolism of toxaphene in fishhave been via water-borne exposure. Fish aresensitive to toxaphene in water. There is also aneed to know how fish react to toxaphenewhen it is ingested through the feed in order toevaluate any possible threats to fish wellbeingand food safety.

Zebra fish are used as a model organism toidentify the toxicity of undesirable substances.A feeding trial has been conducted on theeffects different concentrations and chemicalforms of toxaphene in zebra fish.

The purpose of the study was to determinewhether the different forms of toxaphene areabsorbed in different ways by the fish, andwhether some forms are more toxic thanothers. It is also important to acquireknowledge of how undesirable substancessuch as toxaphene affect fish egg quality,hatching and development. Researchers at

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NIFES are examining how toxaphene affectsthe development of zebra fish embryos andwhether toxaphene is transferred fromspawning fish to the eggs. Zebra fish are verysuitable for this purpose as they spawn year-round. The eggs also develop quickly and aretranslucent, making the development easy tofollow.

In collaboration with: University ofPlymouth and University of Nijmegen.Funding: Research Council of Norway andMinistry of Fisheries and Coastal Affairs.

Synthetic antioxidants infeed – their significance forfood safety

Ethoxyquin (EQ) is a synthetic additive usedin fish feed to prevent it from turning rancidduring storage. It is mandatory to addethoxyquin to fish meal prior to seatransportover long distances, to avoid oxidation andthe subsequent danger of self-ignition. EQ isnot authorised as a food additive in the EU,and is therefore not desired in fish. The EU’supper limit for the sum of the syntheticantioxidants BHA, BHT and EQ in feed is150 mg per kg, and results from monitoringof feeds and feed ingredients show that thecontent of these antioxidants in Norwegianfish feed is below this level.

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Previous studies by researchers at NIFEShave shown that EQ is transferred from thefeed to the fish where it is stored as themetabolite ethoxyquin dimer, EQDM in allof the salmon’s organs, including muscle.NIFES monitors the presence of EQ andEQDM in farmed salmon. In 2008, meanconcentrations of EQ + EQDM in salmonfillet were measured in the range 0.2 – 2.5mg per kg.

Researchers at NIFES have examined thetoxicity of EQDM, and how this substanceaffects fish health and food safety. A 3-monthfeeding trial has been carried out with rats.The animals were given a feed in which thelevel of synthetic EQDM was 2500 times theacceptable daily intake of 0.005 mg per kg ofbodyweight (ADI) established by the ”Joint

FAO/WHO Meetings on Pesticide Residues”for EQ. Preliminary results showed goodgrowth and no visible negative health effectsamong the rats. This indicates that rats cantolerate relatively high doses of EQDM.

Researchers at NIFES will also be examininginteractions between EQ, EQDM and othercommonly used synthetic antioxidants infeeds, such as BHT and BHA.

In collaboration with: University ofBergen, Norwegian University of Scienceand Technology, Trondheim, University ofApplied Science, Switzerland.Funding: Research Council of Norway,Ministry of Fisheries and Coastal Affairsand Fishery and Aquaculture IndustryResearch Fund.

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About ADI - for substances used in food productionAn Acceptable Daily Intake (ADI) is the amount of a substance that a person can eat everyday throughout their life without posing a health risk. ADIs are established by risk assessmentbodies (e.g. EFSA and JECFA) for authorized feed and food additives and are usually givenin mg per kg of body weight.

What are synthetic antioxidants?In the European Union and Norway there are five synthetic antioxidants which are authorizedfor use in fish feed: butyl-hydroxy-anisole (BHA), butyl-hydroxy-toluene (BHT), ethoxyquin (EQ),propyl gallate (PG) and octyl gallate (OG). They are classified as additives with the followingE-numbers: E310 (PG), E311 (OG), E320 (BHA), E321 (BHT) and E324 (EQ). Theseantioxidants prevent the fat in the feed from turning rancid.

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It is a prerequisite that the seafoodwe eat is safe. NIFES carries outseveral annual surveillanceprogrammes which measure thecontent of undesirable substances infish, fish products and fish feed. It isimportant to have updatedknowledge regarding the levels ofundesirable substances in wild andfarmed fish from Norwegian watersto protect consumers, and form thebasis of risk assessments anddevelop sufficient surveillance ofdifferent species.

Recently, research has shown thatthe present surveillance system forwild fish is insufficient. NIFES istherefore in the process of carryingout a thorough surveillance of thelevel of undesirable substances infish from Norwegian waters, so-called “baseline projects”. The aimis to establish background levels ofdifferent undesirable substances inthe most important commercialspecies.

Baseline of environmentalpollutants in major fishspecies

NIFES has started an extensive investigationof undesirable substances in fish species thatare important in Norwegian fisheriesmanagement. The aim of the project is toestablish background levels of differentundesirable substances in the most importantcommercial species in Norway. It isimportant to have updated knowledgeregarding the levels of undesirablesubstances in wild and farmed fish to protectconsumers, and form the basis of riskassessments and targeted surveillanceprogrammes. In 2008 the Institute completedthe baseline study on Norwegian springspawning herring, and in 2010 the baselinestudy for Greenland halibut was completed.New baseline studies have been initiated formackerel, North Atlantic cod, North Seaherring and the saithe in the Norwegian andthe Barents seas.

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Undesirable substances in Norwegian seafood – status

“In 2008 the Institute completed the baseline study onNorwegian spring spawning herring, and in 2010 thebaseline study for Greenland halibut was completed.New baseline studies have been initiated for mackerel,North Atlantic cod, North Sea herring and the saithe inthe Norwegian and the Barents seas”

Greenland halibutNIFES has carried out a comprehensivemonitoring programme on the levels ofenvironmental pollutants in Greenlandhalibut. The results show that the levels ofdioxins and dioxin-like PCBs exceed EU’supper limit in the two positions northwest ofTraenabanken and one at Eggakanten outsideLofoten.

NIFES has initiated a comprehensivemapping of the background levels ofdifferent environmental pollutants inNorway’s most important commercial fishstocks, referred to as baseline studies.Greenland halibut is the second species thatthe institute has established a baseline studyfor, following the one conducted onNorwegian Spring Spawning Herring in2008.

The baseline study on Greenland halibutshows that the levels of dioxins and dioxin-like PCBs, as well as mercury are high infish from several locations. However, whenthe results are evaluated as lots in accordancewith EU legislation the levels of dioxin and

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Figure 1.

dioxin-like PCBs in Greenland halibutexceed EU’s upper limit, at two positionsnorthwest of Traenabanken and one inEggakanten outside Lofoten. The baselinereport of Greenland halibut can bedownloaded on www.nifes.no (available inNorwegian).

Sampling locationsA total of 1288 Greenland halibut from 27locations from four areas; south of Lofoten,Lofoten to Tromsøflaket, East-Finnmark andWest of Bjørnøya towards Svalbard havebeen collected and analysed for severalenvironmental pollutants. Either 30 – 55 fishwere collected from each location. Thesampling locations are shown in Figure 1.

Levels compared with EU legislationBaseline studies are carried out in order toget a comprehensive overview of the levelsof environmental pollutants in seafood fromNorwegian waters, and are tools to ensure anappropriate surveillance of species in thefuture. The fish sampling system is tailoredwith this in mind, and therefore deviatesfrom the requirements set by EU-legislation,

used to evaluate food safety and assess thenecessity of actions in order to meet potentialchallenges. Legislation states thatmeasurement uncertainty should besubtracted from an analytical result before

comparing the value to EU’s upper limits forenvironmental pollutants in food. This isdone in order to ensure that levels whichexceed the EU´s upper limit, do so without“reasonable doubt,” and to ensure that any

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actions are based on a high level of certainty.In addition, EU-legislation states that pooledsamples of five fish should be taken when acatch is between 50 and 500 kg. Theanalytical results in the present report onGreenland halibut have generally beenpresented without subtracting themeasurement uncertainty. In order to evaluatethe results according to EU-legislation,several calculations have been presented inan Appendix of the report. These have beensent to the Norwegian Food Safety Authorityto take appropriate actions.

Three positions pose a potentialchallengeWhen the measurement uncertainty issubtracted from the analytical data, thereappears to be no samples which exceed theEU’s upper limit for mercury in fish of 0.5mg/kg wet weight. However, there aresamples from five locations which exceedEU’s upper limit for dioxins and dioxin-likePCBs, shown in Figure 2. The probability ofidentifying a sample which exceeds EU’supper limit for the sum of dioxins and

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Figure 2.

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dioxin-like PCBs of 8 ng TEQ/kg wet weightin a catch is; approximately 6% for thelocations 3 and 13, approximately 35% forlocation 6, around 31% at location 7 and13% at location 8.

The levels of other environmental pollutantsin Greenland halibut which were measured(including arsenic, cadmium and lead), wherefound to be generally low, thus they are not aconcern for seafood safety.

Future surveillance of GreenlandhalibutOne of the objectives of the baseline studieson fish is to determine the strategy for futuresurveillance of environmental pollutants in agiven species. The results for Greenlandhalibut suggest that surveillance should beannual, and 30 fish should be sampled from atotal of 10 locations. Eight samplinglocations should be in the area from 70°Nand 63°N (from Vesterålen and going south),

and two locations in the area west ofBjørnøya to Svalbard. This will enablespatial and temporal monitoring of thecontent of mercury and dioxins, and dioxin-like PCBs. Greenland halibut is also animportant species in the integratedmanagement plan of the marineenvironments of the Barents Sea and theNorwegian Sea (White paper 37 2008-2009).The proposed monitoring programme willalso support the management plan for thisarea.

Funding: Norwegian Food SafetyAuthority, Ministry of Fisheries and CoastalAffairs and Fishery and Aquaculture IndustryResearch Fund.

MackerelA baseline study for mackerel has started.

Funding: Ministry of Fisheries and CoastalAffairs, Norwegian Fishermen’s` SalesOrganisation for Pelagic Fish, Fishery andAquaculture Industry Research Fund.

Atlantic CodNortheast Arctic cod, North Sea cod andcoastal cod are different cod populationsfound in Norwegian waters. Baseline studyfor cod in the Barents Sea has started.

Funding: Fishery and Aquaculture IndustryResearch Fund.

North Sea HerringBaseline study for North Sea herring hasstarted.

Funding: Fishery and Aquaculture IndustryResearch Fund.

“The results for Greenland halibut suggest that surveillance should beannual, and 30 fish should be sampled from a total of 10 locations”

Continuing the Barents Seamanagement plan

Through the White paper No. 12(2001–2002) entitled ”A clean and rich sea”,the Norwegian parliament has concluded thatthere is a need for more comprehensivemanagement of the Norwegian sea areas. Thefirst stage in this process was the preparationof a management plan for the Barents Seaand the sea areas around the Lofoten Islands.Two working groups were formed, one forThe Risk of Acute Pollution and one forSurveillance, as well as an Expert Forum forthe Barents Sea. NIFES is represented ineach of these bodies.

The Surveillance Group coordinatesmonitoring activity in the Barents Sea. Thisincludes physical parameters, stock levels forvarious fish species and the pollutionsituation which includes the area of ”safeseafood”, where NIFES has a nationalresponsibility.

In 2009, a total of 100 cod fillet and liversamples were collected from four differentlocations, as well as three 5 kg collectsamples of shrimps, capelin and Polar cod,respectively. They were analysed for anumber of substances, including metals,PCB7, dioxins and dioxin-like PCBs,bromated flame retardants (PBDE),pesticides and perfluorated alkylatedsubstances (PFAS). In 22 of 97 cod liversamples the concentration of dioxins anddioxin-like PCBs exceeded EU’s upper limitfor fish liver which is 25 ng TE per kilo wetweight, and from one location the meanvalue was above the upper limit (the resultsare not adjusted for the measurementuncertainty). The surveillance results areincluded in the report from the SurveillanceWorking Group which will be part of thescientific basis to be used when themanagement plan for the Barents Sea isrevised in 2010. The results from theanalysed samples showed low concentrationsof other undesirable substances.

Funding: Ministry of Fisheries and CoastalAffairs.

Management plans for theNorwegian Sea and theNorth Sea

Stage two in the process of preparingmanagement plans for the Norwegian watersrelates to a comprehensive management planfor the Norwegian Sea. NIFES hascontributed within the area of food safety intwo of the reports: ”Proposed indicators ofenvironmental status for the Norwegian Sea”and ”Assessment of status and knowledgerequirement” which formed the basis of themanagement plan for the Norwegian Sea,which resulted in a white paper St. Meld. 37in spring 2009.

NIFES is also represented in the North SeaExpert Group, which is headed by the

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Climate and Pollution Agency. This agency isresponsible for drawing up the managementplan for the North Sea.


Long-term surveillance

Annually, since 1994 NIFES has analysedrandom samples of fish and other seafoodcaught in the Barents Sea, the Norwegian Seaand the North Sea,in order to determine thelevel of undesirable substances and nutrients.What species are analysed and the number ofsamples taken each year varies depending onthe volume of the catch. In 2009 NIFESanalysed pooled sample of fish and shrimpsfrom the Barents Sea. The pooled samplescomprised of 5 kg each. One hundredsamples of cod were also taken fromdifferent locations in the same area. Pooledsamples of 5 kilos were taken of capelin andPolar cod from three locations. Also, pooled

samples of 5 kilos were taken of peeledshrimps and whole shrimps from threelocations. Analyses of cod (100 fish) andsalmon (50 fish) were carried out onindividual fish. The level of undesirablesubstances in capelin, Polar cod, shrimps andcod fillet were low, but the level of dioxinsand dioxin-like PCB was relatively high incod liver. The mean value from one of thelocations was about 25 ng TE/kg wet weight,which is similar to EU’s upper limit. Theseresults were also part of the managementplan for the Barents sea. The Institute alsomonitors the level of undesirable substancesin farmed fish. The status of samplescollected in the course of 2009 showed lowlevels of these substances in various speciesof farmed fish, and a decline in total dioxinsand dioxin-like PCB in farmed salmon.Monitoring thus provides documentation thatfarmed salmon conforms to regulations onseafood safety. The results of the analyses arepublished in Seafood Data(http://www.nifes.no/sjomatdata).


Unique monitoring ofparasites in pelagic fish

A higher sea temperature can lead to anincreased incidence of parasites inNorwegian waters. Since 2004 NIFES hasmonitored the level of parasites in pelagicfish from Norwegian waters, and the Instituteis represented in the European Food SafetyAuthority’s (EFSA) working group for ”Riskassessment of parasites in fishery products”.Monitoring of the parasite status is importantfor food safety, and continuous monitoring isnecessary in order to follow trends in theincidence of parasites. This monitoringactivity is the only one of its kind in the EU.All analyses of parasite monitoring of pelagicfish in Norway are carried out on the vesselswhich made the catch. This ensures that thedata is reproducible and can easily be

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Environmental status ofseafood in Bergen’sCity FjordThe National Institute of Nutrition andSeafood Research (NIFES) has carried outnew research to determine the levels ofenvironmental pollutants in various fishspecies, crabs and blue mussel from Bergen’sCity Fjord and the port of Bergen.

The survey relates to two projects, one underan assignment for the County Governor’sDepartment of the Environment in the countyof Hordaland: ”An extended dietary advicesurvey – Bergen’s City Fjord 2009”, and theother for the Norwegian Food SafetyAuthority: ”Dietary Advice Survey –Recreational Fishing Bergen, 2008-2009”.

The purpose of the survey is to provide newdata on environmental pollutants in fish toenable the appropriate bodies to consider

taking action to reduce the effects ofpollution and, if necessary, to revise dietaryadvice given previously. The areas examinedare marked 1 (port of Bergen) and 2-10(Bergen’s City Fjord) in the map below.

Generally low levels ofenvironmental pollutants invarious species of cod fishand blue mussel

The Norwegian Food Safety Authority haspreviously issued dietary advice for pregnantand breast feeding women advising them toavoid eating fish fillets from lean fish fromspecific areas in the port of Bergen. Whenthis advice was given, few species of leanfish had been examined, but now severalspecies have been studied, including cod,saithe, pollock, whiting, haddock and ling.The new research shows a generally lowlevel of undesirable substances in these fishfrom all of the areas examined. The onlyexception was the level of mercury in fish

compared. In its report to the EuropeanCommission, EFSA states that theNorwegian parasite monitoring activities canalso serve as a model for correspondinginvestigations in other important Europeanfishing areas for pelagic fish. In the event,this will make it possible to compare datafrom several sea areas and thus obtain abetter overview of the parasite status inseveral European sea areas. This knowledgecould also contribute important data for usein a future evaluation of the effect of man-made environmental influences such asclimate changes in the North-East Atlanticpelagic ecosystem.

In collaboration with: Fishery andAquaculture Industry Research Fund, ThePelagic Industry (fleet and land-based).Funding: Ministry of Fisheries and CoastalAffairs.

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fillet from Eidsvågen in Åsane which wasabove the level used by the food authoritieswhen they made their dietaryrecommendation for pregnant and breastfeeding women. Previously, high levels ofmercury had been found in cusk and lingfillets close to the centre of Bergen, andslightly elevated levels were found in cod.

Apart from the area around Eidsvågen andcod in the port of Bergen, there may bereasons to revise the current dietary adviceconcerning low-fat fish from the areasexamined.

The levels of environmental pollutants inblue mussel were low in all of the areasexamined. The exception was the area fromSotra North to Askøy (Ramsøy), where theremay be a local source of pollution.

High levels of environmental pol-lutants in fish liverAnalyses of fish liver reveal high levels ofenvironmental pollutants such as dioxins and

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Figure 3.

dioxin-like PCBs. Dietary advice about fishliver is already in place, and the new researchgives no fundation to revise this advice.

Is there reason to revise the outerlimits for dietary advice on crab,cusk and eel in Bergen’s City Fjord?Our analyses have increased the knowledgebase on environmental pollutants in cusk, eeland brown crab in Bergen’s City Fjord,which might become useful in case of arevision of how far out from the port ofBergen the existing dietary advice relating tothese species should apply (see fig. 3).Nationwide dietary advice about brown crabmeat is already issued which recommendspregnant women to avoid eating brown crabmeat.

Samples were taken from thefollowing species:- Fillet and liver samples from cod (Gadus

morhua) *- Fillet and liver samples from saithe **

- Fillet and liver samples from pollock **- Fillet and liver samples from whiting **- Fillet and liver samples from haddock **- Fillet from cusk (Brosme brosme) *- Fillet from ling (Molva molva) *- Fillet from eel (Anguilla anguilla) *- Brown meat from edible crab (Cancer

pagurus) *- Entire contents from pooled samples of

blue mussel (Mytilus edulis)*

* Species/samples taken in areas on mapmarked 2, 3, 4, 5, 6, 7, 8, 9, 10

** Species/samples taken in areas on mapmarked 1, 3, 4, 5, 8

(1=Bergen port, 2=Askøy-Åsane,3=Nordhordland Bridge, 4=Askøy-Meland,5=Sotra North-Askøy, 6=Grimstad Fjord,7=Nordås Lake, 8=Sotra South-Hjellestad,9=Kollevåg, 10=Flesland)The above species were selected as they are

especially predisposed to accumulate certainkinds of environmental pollutants while atthe same time they represent different kindsof seafood.

The species were analysed for thefollowing undesirables:

Species marked *were analysed forarsenic, mercury, lead, cadmium, PCB7,dioxins, dioxin-like PCB and polyaromatichydrocarbons (PAH).

Exceptions: Cod fillet and blue musselswere only analysed for metals. Blue musselswere only analysed for metals and PAH.

Species marked ** were analysed forarsenic, selenium, mercury, lead, cadmiumand PCB7.

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“Our analyses have increased the knowledge baseon environmental pollutants in cusk, eel andbrown crab in Bergen’s City Fjord”

Surveillance inproximity to shipwrecksShipwrecks can contain environmental toxinsand they represent a challenge to food safetyif the pollutants start to leak out. Therefore,NIFES examines and monitors the level ofenvironmental pollutants in various speciescaught in and around the wreck of submarineU-864 off Fedje and MS Welheim near Florø.NIFES has also assessed food safety ofseafood caught in connection with emissionsfrom Full City and Petrozavodsk. NIFESparticipates in the Norwegian CoastalAdministration’s Surveillance Group.

Monitoring by thesubmarine wreck U-864off Fedje

West of Fedje lays the wreck of the Germansubmarine U-864 at a depth of 150 metres. Itmay have contained 60-70 tons of mercurywhen it was torpedoed in 1945. In order to

assess food safety, NIFES has therefore since2004, monitored the level of mercury in fishand crabs from this area on behalf of theNorwegian Coastal Administration todetermine whether the seafood is affected bymercury in the area. Analyses have beencarried out on the species it has been possibleto catch in fish traps.

In 2009 NIFES measured the level ofmercury in tusk and crab as it is almostexclusively these species that have beencaught in this area in the last few years.Samples were taken near the wreck, and fournautical miles north and south of the wreck.

Uncertain if tusk is affectedThe results for 2009 show that the level ofmercury in tusk fillet is in line with theaverage for previous years. Throughout themonitoring period, from 2004 to 2009, a totalof 322 tusk were analysed. Although themean values for mercury in tusk caught inthe area near the wreck have always beenbelow the EU’s upper limit value of 0.5 mgper kg wet weight, levels exceeding this werefound in 17 individual fish, of the 322

analysed. Most of these higher levels werefound during monitoring in 2008, while in2009 two of 75 analysed fish had levelsexceeding EU’s upper limit. Nevertheless,the tusk from the area around Fedje do notshow especially high levels of mercurycompared with tusk caught elsewhere.

Crabs are probably affectedThe results of analysis carried out in theperiod 2004-2009, of a total of 297 crabs,show that only claw meat from one crabhad a level of mercury that was above theEU’s upper limit of 0.5 mg per kg wet weight(the results are not adjusted for themeasurement uncertainty). Monitoring alsoshows that the level of mercury in browncrab meat was relatively high, compared withother areas. This is probably due to the crabbeing polluted by the mercury in sedimentsaround U-864. The result from 2009 showsthat the mercury levels in crabs wasconsiderably lower than in previous years.The reason for this may be that the crabs in2009 were caught later in the year and inshallower water, and thus further away from

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the wreck, than previous years. EU has noupper limit for mercury in the brown crabmeat. During the entire period, sevenindividual crabs had a mercury level inbrown meat that exceeded 0.5 mg per kg wetweight. In 2009, none of the samples showeda measured value above 0.5 mg per kg wetweight.

Still dietary adviceThe Norwegian Food Safety Authority haspreviously issued a dietary advice whichrecommend pregnant and breast-feedingwomen to avoid seafood from the areaaround the wreck. The new analyses do notchange the food safety situation.

Important to continue monitoringAs individual specimens of different specieshave been shown to have a level of mercurythat is above the EU’s upper limit value, andas the pattern of dispersion of mercury couldchange, it is important to continuemonitoring the level of mercury in seafood inthis area. NIFES recommends continued

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monitoring of seafood, regardless of whatsteps are taken to deal with the wreck.

Funding: Norwegian CoastalAdministration.

Analysis of seafood takenaround MS Welheim

The wreck of MS Welheim is located about10 km south of Florø on a sloping seabed, ata depth of 30 -65 metres. The ship sunk in1944 and may have had between 300 and1200 tons of diesel oil on board. For severalyears there have been several minor leakagesfrom the wreck. NIFES are examining thelevels of the environmental pollutants PAHand PCB in samples of Norwegian lobster,brown crab meat, blue mussel, tusk, ling andfarmed fish around the wreck before and

after emptying it for oil. Diesel oil containspolyaromatic hydrocarbons (PAH), some ofwhich are toxic and can damage hereditarymaterial and may be carcinogenic.Polychlorinated biphenyls (PCBs) are health-hazardous synthetically produced compoundswhich are oil-soluble. NIFES will alsomeasure the level of PCB and PAH in farmedfish from three localities in the vicinity.

The wreck has now been emptied, and thesamples were collected by the NorwegianFood Safety Authority before emptying.Samples taken after emptying will becollected in spring 2010. The results will beavailable when the samples after emptyinghave been collected and analysed.

Funding: Norwegian CoastalAdministration.

Evaluation of food safetyafter oil spillsPolyaromatic hydrocarbons (PAHs) are foundin crude oil and various oil products. Thesubstances can be detrimental to consumers`health. In connection with oil spills, theeffect on food safety is assessed by analysingthe level of the PAH compoundbenzoapyrene (BaP) in seafood samples. BaPis one of the most toxic PAH compounds.

“Full City”In July 2009 the cargo ship ”Full City” ranaground outside Langesund in Telemark. TheNorwegian Coastal Administration wasresponsible for co-ordinating theenvironmental assessment and remediationafter the oil spill. NIFES was responsible forassessing the seafood safety aspect. Samplesof cod, saithe, haddock, pollock, eel,mackerel, crab and blue mussel wereanalysed for PAHs.

The results showed low levels of BaP in thefish fillets and in brown crab meat. The

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“NIFES are examining the levels of the environmentalpollutants PAH and PCB in samples of Norwegian lobster,brown crab meat, blue mussel, tusk, ling and farmed fisharound the wreck before and after emptying it for oil”

values were below the EU’s upper limit. TheBaP levels in mussels from several impactedlocations were high, exceeding EU’s upperlimit for BaP in mussels. Based on theseresults, NIFES recommended that theNorwegian Food Safety Authority maintainthe consumption advisory to avoid eatingmussels which was issued for this areaimmediately after the oil spill, based on theprecautionary principle.

PetrozavodskIn May 2009 the freezer ship Petrozavodskran aground outside Bjørnøya in Troms,resulting in diesel leakage. NIFES wasrequested by the Norwegian CoastalAdministration to assess whether seafoodcaught in the vicinity of the grounded vesselwas safe to eat. Samples of cod liver wereanalysed for PAHs and PCB.

As mentioned above, the effect of oil spills

on food safety is assessed by analysing thelevel of the PAH compound benzoapyrene(BaP). The BaP levels in all of the liversamples which were analysed were below thequantification limit. This limit is below theEU’s upper limit for BaP in fish which is 2mg per kilo. It was not considered necessaryto advise against eating cod liver from thisarea on the basis of the results from theanalyses conducted.

In collaboration with: The NorwegianCoastal Administration, the Institute ofMarine Research and the Norwegian FoodSafety Authority.Funding: Norwegian CoastalAdministration.

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Quantification limitThe smallest amount of a compound thatcan be determined with a givenuncertainty.

Oil spill from «Full City» outside Langesund. Picture from The Norwegian Coastal Administration.

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Surveillance for theNorwegian FoodSafety Authority

Status report on the levelsof undesirable substancesand drug residues infarmed fish

The levels of contaminants in farmed fishfillets largely reflect the feed the fish hasconsumed. Commercial fish feed is regulatedby EU directives which Norway alsoimplement. Thus the EU and Norway haveestablished maximum levels in feed forseveral pollutants, such as dioxins anddioxin-like PCBs and heavy metals. TheNorwegian Food Safety Authority has aprogramme for monitoring the levels ofundesirable substances in fish feed, whichalso covers feed ingredients, as well as amonitoring programme on drug residues andthe levels of certain environmental pollutantsin farmed fish.

Farmed salmonPollutants such as PCB7 and heavy metals insalmon fillets have been monitored for morethan 10 years, while dioxins and dioxin-likePCB have been included since 2004.Documentation of the levels undesirablesubstances in salmon comes from twosources; one is NIFES’s surveillanceprogramme which examines individual fishand these results can be accessed in NIFES’ssearchable database(http://www.nifes.no/seafooddata), while theother is the Norwegian Food SafetyAuthority’s surveillance programme linked toEU Directive 96/23 (these reports can beaccessed on the websites of both theNorwegian Food Safety Authority andNIFES).

The levels of pollutants in salmon fillets in2009 were low compared with the EU’supper limits for those pollutants where suchvalues have been established. The level ofdioxins and dioxin-like PCBs in salmon filletis approximately 1/8 of the limit set by theEU and Norway for the legal sale of seafood,and is comparable to the levels found in oily

fish species such as mackerel, spring-spawning herring and North Sea herring. Asyet, no upper limit has been set for PCB7 inthe Codex or by the EU or Norway, but thelevels are low and largely comparable withthe levels found in mackerel, spring-spawning herring and North Sea herring. Asregards the presence of the heavy metalsfrom 2009, The levels of mercury, cadmiumand lead in farmed salmon, stated as a

Deloucing agents in fishStatistics of pharmaceuticals used in fishfarming published in 2009 (NorwegianInstitute of Publich Health) shows anincreased use of deloucing agents. In2009 NIFES analysed around 9000samples from fish for a variety of differentsubstances. For delousing agents, 725 fishwere analysed, and 145 fish wereexamined for residues of diflubenzuronand teflubenzuron. The surveillance did notreveal any use of illegal substances orresidues of legally used substances abovethe internationally set limits. Therefore, theuse of pharmaceuticals for farmed fish didnot affect seafood safety.

percentage of the EU’s upper limit are 6%,4% and 3%, respectively. The levels ofdioxins and dioxin-like PCBs and PCB7 havedeclined in recent years, while the heavymetal concentrations are low and show astable trend.Farmed troutFarmed trout is included in the NorwegianFood Safety Authority’s surveillanceprogramme and the results found forpollutants in this species are comparable withthose reported above for farmed salmon.Farmed codFarmed cod is a lean species with a low fatcontent and the levels of organic pollutantssuch as dioxins and PCB in the fillet areabout 1/10 of the concentrations found inoily fish species, but are comparable with thelevels found in wild cod. Similarly the levelsof heavy metals in farmed cod are similar tothose measured in wild cod.

Drug residues in farmed fishIn order to ensure that farmed fish for humanconsumption do not contain remnants of

approved drugs, including anti-lice agents, inquantities that represent a health risk, orresidues of unauthorised drugs, Norway has asystem of controls that is in completeconformity with international guidelines. Thesystem was introduced in Norway at the endof the 90s and is based on the control andregistration of drug use, the establishment ofretention periods which ensure that the fishcannot be harvested until a specified periodhas elapsed after drug treatment, andanalytical controls to determine any presenceof drug residues in farmed fish. Analyses ofsamples taken in 2009 and previous yearshave not shown any remnants ofunauthorized drugs, or remnants ofauthorised drugs above internationallyaccepted levels.

Surveillance systemUnder international regulations, Norway iscommitted to monitor the level of certaindrugs and environmental pollutants in farmedfish. These regulations also apply to all otherfood-producing livestock and products ofanimal origin. The Norwegian Food Safety

Authority is responsible for sampling, wherasNIFES carries out the analyses and isresponsible for reporting on issues related tofarmed fish. The system is monitored by theEFTA Surveillance Authority (ESA) whichensures that EU law is correctly enforced inEFTA states. The samples taken in 2009 werefrom approximately 9000 farmed fish. Thesurveillance results are published in publiclyavailable reports which can be accessed atwww.nifes.no

Marine oils for humanconsumptionCod liver oil and marine oils are purified toeliminate undesirable substances beforebeing sold as a food supplement. Data fromprevious years’ research shows that cod liveroil and other marine oils, in addition to fattyfish and seafood products, are mostpredisposed to accumulate fat-solubleorganic environmental toxins such as dioxinsand dioxin-like PCB.

In 2009, 10 samples of fish oil and sixsamples of seal oil were analysed. The total

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level of dioxins and dioxin-like PCB wasbelow the EU’s upper limit of 2.0 ng TE perkilo in all of the 21 samples analysed. Noneof the samples were above the Norwegianupper limit of 5.0 ng TE per kilo of fat fortotal dioxins and dioxin-like PCB, and notabove the EU’s upper limit value of 10 ng TEper kilo of fat. The data basis for dioxins anddioxin-like PCB in food is still very limitedin both Norway and the EU. It is thereforeimportant that Norway contributes tostrengthening this data basis, especially in thearea of seafood.Funding: Norwegian Food SafetyAuthority.

Low levels of undesirablesubstances in mackerel fromGrenland Fjord area

Analyses showed that there were low levelsof heavy metals, brominated flame retardants(total PBDE and total HBCD), dioxins anddioxin-like PCB in five pooled samples, eachcomprising five mackerel from the Grenland

Fjord and surrounding areas along the coastof Telemark. The levels were comparablewith the levels found in mackerel caught inthe North Sea and the Norwegian Sea.Funding: Norwegian Food SafetyAuthority.

Low levels of undesirablesubstances in Svolvær paste

The sandwich filling called Svolvær pastecontains fish liver. The levels of PCB in fishliver can vary, but the level is high enoughfor the Norwegian Food Safety Authority toadvise children and women of child-bearingage or those who are breast feeding to avoideating fish liver. NIFES has analysed thelevel of undesirable substances in pooledsamples consisting of five tins of Svolværpaste. The level of PCB and otherundesirable substanses were low in thesesamples and below the EU’s upper limits,where these have been set.Funding: Norwegian Food SafetyAuthority.

High dioxin levels in eelfrom the Grenland Fjordarea

NIFES has determined the content of theheavy metals cadmium and lead in 25random samples of eel fillet from theGrenland area. The levels were below EU’supper limit. This was also the case formercury. Nevertheless, the eel samples fromthe Grenland Fjord contained more mercurythan eel samples taken from unpolluted areas.

Measurements of dioxins and dioxin-likePCBs in the same eel samples showed levelsof these substances exceeding EU’s upperlimit of 12 ng TE per kilo. In the samplesfrom the Eidanger Fjord the level of totaldioxins was more than 10 times higher thanthe EU’s upper limit of 4 ng TE per kilo. Thelevel of dioxins and mercury in the eelsamples which were analysed, particularlythe level in the eels caught in the EidangerFjord, indicates that there is a source ofpollution in the area.

The Norwegian Food Safety Authority hasgiven a dietary advice for the GrenlandFjord, which includes a recommendation toavoid consuming eel from specific areas.

The Directorate of Fisheries stopped all eelfishing in August 2009 and has placed a totalban on eel fishing from 2010. The banapplies to both recreational and professionalfishing.

Funding: Norwegian Food SafetyAuthority.

Low levels of undesirablesubstances and varyingmicrobiological quality insushi

NIFES has analysed the level of undesirablesubstances in a total of 25 samples of sushifrom restaurants and retailers in Bergen andTrondheim. Each sushi sample consisted of a

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mixture of different seafood products, rice,vegetables, condiments and, in some cases,sauces.

Undesirable substansesThe content of undesirable substances waslow in all of the samples analysed, and thelevels of heavy metals, the PAH compoundbenzo(a)pyrene, dioxins and dioxin-likePCBs were below EU’s upper limits forthese substances. The level of the undesirablesubstanses which were the subject of theanalysis (arsenic, inorganic arsenic,tributyltin, several PAH compounds, PCB,DDT and other chlorated pesticides as wellas bromated flame retardants) were very low,and in many cases below the quantificationlimit. No upper limits have been establishedby the EU for these compounds. No traces ofdrug residues (seven different compounds)were found in any of the 13 samplesanalysed.

Listeria, enterococci, E.coli andSalmonellaListeria monocytogenes is a bacterium whichis commonly found in nature and occursoccasionally in seafood. In rare cases it cangive rise to the disease listeriosis in humansand animals.

In 2009 a total of 50 sushi samples wereanalysed for L. monocytogenes, and eachsushi sample consisted of a mixture ofdifferent seafood products, rice, vegetables,condiments and, in some cases, sauces. Thebacterium was found in 20% of the samples.In all of the positive samples, the number ofbacteria was less than 10 bacteria per gram,and thus well below EU’s upper limit of 100bacteria per gram of fresh food product. Thisupper limit is valid at the end of the shelf lifeand assumes that the product is intended forconsumption by healthy adults. Given theshort shelf life stated for sushi, the scope forL. monocytogenes to replicate itself islimited.

E. coli and enterococci are used as indicatororganisms for faecal pollution, and thus apossible health risk. E. coli was found in atotal of 18 of the 50 samples analysed,indicating that there is scope for improvingthe hygienic standard in the production ofsushi. In an international context, bacteriarelated to the Salmonella genus are amongthe commonest causes of infections fromfood products. However, only very rarely doseafood products produced in Norwaycontain Salmonella, and none of the 50 sushisamples analysed contained this bacterium.Some parasites, such as the intestinal worm(Nematoda), can represent a threat to humanhealth, but no parasites were found in any ofthe samples examined.


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Monitoring of shellfishShellfish have a special ability to accumulatemetals. They may therefore have relativelyhigh levels of undesirable metals such ascadmium, lead and inorganic arsenic. InJune 2008 the Norwegian Food SafetyAuthority published a dietary advice relatedto the consumption of scallops and horsemussels due to the high level of bothcadmium in the digestive gland of scallops aswell as lead and cadmium in the kidney ofthe horse mussel. NIFES carries outmicrobiological analysis of the presence of E.coli, enterococci and Salmonella, as well aschemical analyses of undesirables (metals,DDT, PCB, dioxins, polybrominated flame

retardants and PAH) in shellfish and crab onbehalf of the Norwegian Food SafetyAuthority. However, the data basis is stillunsatisfactory for shellfish, with the possibleexception of the blue mussel. Based onrandom sampling, the examinations show agenerally low level of undesirablesubstances, and a mainly goodmicrobiological quality of shellfish.

Mainly good microbiologicalquality of shellfish

Shellfish can absorb gastrointestinal bacteriasuch as E. coli, enterococci and Salmonella ifthey are found in the water where the

shellfish grow. Analyses of E. coli andenterococci are used to identify faecalpollution, and thus possible health risks.

Among a total of 388 samples analysed forE. coli, 337 (87 %) had concentrations whichwere below the limit for classification as anA-location, which means that they can betaken directly for consumption.Concentrations of E. coli corresponding to aB-location were found in 46 samples, whilethe level found in five samples correspondedto a C-location. Shellfish from B- and C-locations must be replaced or heat treatedbefore they can be sold. Enterococci werefound in eight of the 388 samples analysed.

There are more than 2500 variants ofSalmonella bacteria. Many of them causeinfection in humans, and foodstuffs shouldtherefore not contain Salmonella bacteria.Salmonella was not found in any of the 61samples analysed.


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“The data basis is still unsatisfactory for shellfish, with thepossible exception of the blue mussel. Based on randomsampling, the examinations show a generally low level ofundesirable substances, and a mainly good microbiologicalquality of shellfish”

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Low level of undesirablesubstances in shellfish

NIFES monitors the level of undesirablesubstances in several species of shellfish. In2008, 62 samples of blue mussel were takenfrom 36 different locations along the entirecoast. The level of metals in blue mussel wasthe same as previous years, and none of theheavy metals cadmium, mercury or lead werein concentrations that exceeded EU’s upperlimit. The levels of dioxins and dioxin-likePCB, PCB7 and bromated flame retardantswere low in the nine blue mussel samplesthat were analysed for these substances.

Previously, high levels of cadmium and leadhave been found in the horse mussel kidney,as well as high concentrations of cadmium inthe digestive gland of the scallop.The Norwegian Food Safety Authority hastherefore published dietary advicerecommending the public to avoid eating thekidney from horse mussels and the dietarytract of scallops.

Monitoring of horse mussels involvedanalysis of the entire soft parts, while onlythe mussel and roe of the scallops wereanalysed (most commonly consumed inNorway). The two horse mussel sampleswhich were analysed had a cadmium levelabove EU’s upper limit of 1.0 mg per kilo,while the level of lead was below the limit of1.5 mg per kilo. This underpin theimportance of following the dietary advicefrom the Norwegian Food Safety Authoritywith respect to scallops and horse mussel.The levels of polyaromatic hydrocarbons(PAH) were below the quantification limit forhorse mussel. The muscle and roe of theanalysed scallops had a generally low levelof both heavy metals and PAH.


Grading oyster quality

In the European market, the flat oyster isconsidered to be the most exclusive species

of oyster. Norway has never had a stronghome market for oysters, and nor is there anyquality standard for the flat oyster.

In cooperation with several other institutions,NIFES has carried out a study of seasonalvariations in quality at three locations byBømlo in Sunnhordland. The work was basedon simplified, but practical methods wherebythe visual degree of fullness, the sweetness oftaste and the mineral taste were all assessedon a scale with defined categories. Tastingwas done by two shellfish researchers fromthe Marine Research Institute and NIFES.This was done in a rudimentary fashionwhich made it possible to assess more than600 oysters over 10 different time periods,and within a limited budget.

The visual degree of fullness was consideredto be the most appropriate quality target forpractical use in the oyster industry.

A tool in the form of a chart with text andphoto has been developed for this purpose.Some instruction and experience is required

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to be able to judge the oyster effectively withregard to the visual degree of fullness. Theadvantage is that the method is quick and hasdirect relevance for the quality in the sensethat the visual impression is an importantpart of the quality.

The results from the study of seasons showthat the visual degree of fullness is wellcorrelated with the sweetness of taste. Mostof the oysters were good, but nevertheless theresults show a clear connection with the timeof year, with the quality peaking aroundChristmas time.

In collaboration with: Bømlo Skjell AS,Vest i havet AS and Institute of MarineResearch.

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Photo:

ArneDuinker

Environment and effecton seafood safety

How are cod in a seawaterinlet in Bergen affected byenvironmental pollutants?

In the process of establishing biomarkers forenvironmental pollutants in fish and studyinghow these substances affect fish health andseafood safety, researchers at NIFES haveexamined the gene expression in cod fromthe Store Lungegårdsvann, a seawaterrecipient in Bergen. This is an area definedas relatively polluted, with considerableamounts of organic environmental pollutantsin the sediments. Cod sampled at thislocation was compared with cod from theouter Hardanger Fjord, which is not

considered to be a polluted area. The genesexamined code for proteins known torespond to environmental pollutants oftenfound in sewage and surface drainage waterin urban areas.

The findings showed that cod in the StoreLungegårdsvann are exposed to organicenvironmental pollutants which affect theexpression of genes which are important forthe detoxification mechanisms of the cod.The expression of two of these genes differsin the male and the female cod. The resultsindicated that the male cod are affected byenvironmental oestrogens. These aresubstances which mimic natural oestrogen inthe body and which have a disturbing effecton natural hormonal processes.

The effects may be due to organicenvironmental pollutants or the discharge of

sewage and indicates a stress response in thecod. Follow-up studies with measurement ofthe proteins which these genes code for arenecessary before it can be determinedwhether these gene expressions can be usedas biomarkers for environmental pollutants infish.

In collaboration with: University ofBergen.Funding: Research Council of Norway.

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What is meant by geneexpression?All cells in the body have a cell nucleuswhich contains DNA. The DNA containsgenetic sequences which define thestructure of different proteins with differentfunctions. For a protein to be created, theDNA must undergo a process whereby thegenetic sequences are transcribed tomRNA, which is transported out of the cellnucleus. The term “gene expression”means the amount of mRNA in a cell or atissue at a given time.

“The findings showed that cod in the Store Lungegårdsvannare exposed to organic environmental pollutants whichaffect the expression of genes which are important for thedetoxification mechanisms of the cod”

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Does oil production affectthe reproductive pattern ofthe cod?

Environments can contain environmentalpollutants which can have various effects onfish health and wellbeing. Alkylphenols arecomponents of crude oil. They are found inproduced water, which is the water that isproduced along with the recovered crude oil.These substances, known as tensides, areused in a number of products, includingdetergents.

There are several kinds of alkylphenols.Some of them are long-chain compoundswhich may be the cause of hormonaldisturbances. Researchers at NIFES haveanalysed the expression of vitellogenins(female egg yolk proteins) in female codexposed to environmentally relevant doses ofalkylphenols. The results showed that theproduction of these proteins decreased whenthe female cod were exposed to alkylphenols,and at the same time the maturing processof the gonads is delayed. This means that the

reproductive pattern of the cod is delayed,and if this period is prolonged it will havesignificance for the number of fish larvaethat survive.

In collaboration with: Marine ResearchInstitute.Funding: Research Council of Norway.

Combination effects ofenvironmental pollutants insalmon

Novel substances and products arecontinuously being produced and newpollutants are released in nature, adding tothose that already exist. Animals and humansare commonly exposed to the combinedeffects of these pollutants through food, airand water, and in order to protect us againstenvironmental pollutants in food they aresubject to risk assessments.

Dioxins and dioxin-like PCBs areenvironmental pollutants which break down

slowly in nature and may have detrimentaleffects. Over the last 20 years attempts tocombat pollution have greatly reduced thelevel of these substances in food products.

The toxicity of environmental pollutants isknown to vary, depending on whether theyact together or alone, but we have littleunderstanding of the way dioxins and dioxin-like PCB affect their respective toxicities.Environmental pollutants can accumulate infish and other animals. The liver is the maindetoxification organ of the fish. Theexpression of genes from liver cells sayssomething about which cell mechanisms areaffected. In one study, liver cells fromsalmon were exposed to either non-dioxin-like PCB (PCB 138), or the dioxinspentachlorodibenzo-p-dioxin (1,2,3,7,8-PCDD) and tetrachlorodibenzofuran(2,3,7,8,-TCDF) alone, or a mixture. It wasseen that the two dioxin compounds wereless toxic when acting together thanseparately, while the non-dioxin-like PCB138and dioxin were more toxic when actingtogether than separately.

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For several dioxin-like compounds toxicity ismeasured using Toxic Equivalent Factors(TEFs). TEFs gives an indication of therelative toxicity of a dioxin-likeenvironmental pollutants compared to thedioxin compound 2,3,7,8 -TCDD, which isknown to be most toxic. When mixtures of

several dioxin-like environmental pollutantsare assessed, the concentration of eachsubstance is multiplied by its TEF- value andthe sum of these values is used as a measureof how potentially toxic the mixture is givenin toxic equivalent, TEQs.

PCB 138 has not been assigned a TEF sinceit is not a dioxin-like PCB. The studytherefore shows that in some situations theTEQ may underestimate the toxicity ofcompounds when they are present in amixture.

As the study was carried out on liver cellsthe results are not necessarily representativefor the whole fish. Likewise, changes at themRNA level do not necessarily reflect effectson proteins in the cells. Nevertheless, theresults give some indication of whichmechanisms are affected in the liver cells,and in this respect cells can be used as a toolto identify possible effects before conductingstudies with live animals.

Funding: Research Council of Norway andMinistry of Fisheries and Coastal Affairs.

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Risk-benefit assessments fromseveral countries have concludedthat seafood is safe and healthyand is a natural part of a healthyand varied diet. Nevertheless, theseassessments highlight the need formore research in order tounderstand how nutrients andcontaminants in seafood interact,and what their overall effects areon our health. This knowledgetogether with dietary surveys willhelp us to develop targetedrecommendations related toseafood consumption.

Is mercury toxicity affectedby nutrients in the fish?

Fish and other seafood are a good source ofseveral nutrients, such as selenium, but mayalso contain methyl mercury, one of the mosttoxic forms of mercury in nature. Throughanalysis of behaviour and gene expression inthe brain, researchers at NIFES havepreviously shown effects on gene expressionin the brain of offspring from mice whichhad been fed different chemical forms ofmethyl mercury in the feed. Gene expressionwas most affected by protein-bound methylmercury in the feed. Changes in the brain asa result of exposure to mercury affectedmotor skills and behaviour.

The combined effects of selenium andprotein-bound methyl mercury on braindevelopment, behaviour and motor skillshave been assesed in offspring of dams feddiets containing either selenium or mercuryor both selenium and mercury duringgestation and lactation. Results from thesestudies showed that if the mice were givenboth protein-bound methyl mercury and

selenium in the feed, the selenium protectedthe young mice against the negative effectsof protein-bound methyl mercury.

A feeding trial has been conducted todetermine whether the composition ofnutrients in different fish species givesprotection against the toxic effect of protein-bound methyl mercury in young mice. Damswere fed a mercury-containing salmon-basedor cod-based feed during gestation andlactation. Again, the effects on geneexpression in the offsprings’ brain, and theirmotor skills and behaviour will be analysed.

In collaboration with: Kings CollegeLondon, NTNU, University of Canterbury,New Zealand.Funding: EUs 6th framework programmeproject “Aquamax”, the Research Council ofNorway and the Ministry of Fisheries andCoastal Affairs.

Zebrafish

Zebrafish are commonly used as a model

Interactions between environmental pollutants and nutrients

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system for the study of biologicaldevelopment. Researchers at NIFES arestudying how mercury affects the developmentof the nervous system in embryos when thezebrafish has been exposed to feed containingmercury during gestation. Results to date showthat mercury is transferred from the female tothe embryo, and that nerve cells, which controlthe motor function showed developmentmalformations in the embryo. Further studieswill determine whether selenium cancounteract these malformations when femalefish are given feed containing both mercuryand selenium.

Knowledge of how environmental pollutantsin feed affect fish development is important inorder to safeguard fish health and food safetyfor the consumers.

In collaboration with: National ResearchInstitute of Fisheries Science, Japan.Funding: Research Council of Norwayand the Fishery and Aquaculture IndustryResearch Fund.

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Seafood may contain methylmercury, but usually in concentrations that areconsiderably lower than the EU’s upper limit for mercury in fish of 0.5 mgper kilo of fillet for most species and 1 mg per kilo for some predatory fishspecies, such as tuna and Atlantic halibut.

Interactions betweennutrients in salmon and PCB

Many pregnant women avoid eating fishduring pregnancy due to environmentalpollutants that may be present in seafood thatcould potentially damage the foetus.However, seafood is a source of manyimportant nutrients, such as omega-3 fattyacids which we know are important for thedevelopment of the brain.There are 209 different PCB compounds.PCBs are fat-soluble and are found in oilyfish and other seafood. Long term exposureto PCB can weaken the immune system,affect reproductive ability, lead to thedevelopment of cancer, and disturb thebody’s hormone balance. The foetus andinfants are most vulnerable to negativeeffects of PCB.PCB-153 is one of the most commonlyoccurring forms of PCB in the environment.In order to determine the effect of thissubstance on the development of young mice,researchers at NIFES have carried out

preliminary feeding trials where gestatingand lactating dams were given PCB-153 indifferent types of feeds (either casein- orfish-based). The purpose was to determinewhether nutrients in the salmon had anyameliorating effect on PCB-153.

The fish-based feed did not lead to a loweraccumulation of PCB-153 in the motherscompared with the results from a feed basedon milk protein. It was shown that PCB-153was effectively transferred to the offspringand was present in their liver and fattytissues. Fish-based feed provided limitedprotection against the transfer of PCB-153from mother to young, compared with aprevious trial carried out at NIFES, wheremice were given fish-based feed containingthe brominated flame retardant PBDE-47.Results also indicate that there was littledifference between the behaviour of offspringfrom mice that had been given casein-basedfeed containing PCB-153 versus offspring ofmice fed on fish-based feed containing PCB-153.Increased knowledge regarding interactions

between nutrients and contaminants inseafood contributes to risk-benefitassessments by national and internationalbodies such as the Norwegian ScientificCommittee for Food Safety, and theEuropean Food Safety Authority and toprovide science-based dietary advice forsusceptible consumer groups, such aspregnant and breast-feeding women, andinfants.

In collaboration with: Kings College,London and Instituto Superiore di Sanità,Italy.Funding: EU’s 6th Framework Programmeproject “Aquamax”, Ministry of Fisheriesand Coastal Affairs and Research Councilof Norway.

Salmon silage is a possiblesource of bioactivecomponents

By developing functional food, a dietarysupplement over and above basic

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requirements, it is possible to influence oneor more of the body’s processes in abeneficial way and thus improve health andreduce the risk of illness. An example offunctional food is food to which so-calledbioactive peptides have been supplemented.One source of peptides from seafood isprotein fractions that can be extracted fromsalmon silage following salmon production.To determine whether salmon silage containsbioactive components, it is necessary toanalyse the level of undesirable substances inthe protein fractions. A high level ofundesirables is unfavourable if bioactivepeptides are to be used in the futureproduction of food. NIFES has thereforeexamined different protein fractions andfound that the level of undesirables was low.The Institute has also initiated a feed trialwhere mice are given these protein fractionsin the feed in order to determine whetherthey have a negative effect on health.In collaboration with: University ofBergen. Funding: NordForsk, the Nordicresearch councils, Ministry of Fisheries andCoastal Affairs.

Do plant oils in feed affectintake of mercury bysalmon?

Plant oils and plant proteins are currentlyused as alternatives to marine raw materialsin fish feed. Fish and other seafood may alsocontain environmental pollutants and otherundesirable substances, which couldrepresent a challenge to fish health and foodsafety.

We have limited understanding of the waypositive and negative components in seafoodinteract and what effect they have on fish andthus on food safety. In order to establishwhether plant oils in the feed limited orincreased the intake of environmentalpollutants from feed, researchers at NIFEScarried out a feeding trial where salmon weregiven feed where the main component waseither plant oils or fish oils, both with highmethyl mercury present in the feed. Methylmercury is a harmful mercury compound thatmay be present in seafood. However, it isimportant to note that levels of methylmercury in farmed salmon are low. The

results showed that the source of fat in thefeed had no significance for the intake ofmethyl mercury in the fillet. In other words,neither plant oils nor fish oils in the feedprotect the salmon against exposure tomercury through the feed.


The marine omega-3 fattyacid EPA protects cellsagainst mercury

Laboratory cell cultures are an effective toolto determine which biological and geneticmechanisms are affected by various kinds ofnutrients and undesirable substances.

Researchers at NIFES have carried out astudy where kidney cells from salmon wereexposed to a mixture of methylmercury and,respectively, the marine omega-3 fatty acidEPA, the marine omega-3 fatty acid DHA, orthe omega-6 fatty acid arachidonic acid.

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The cells were compared with cells that hadonly been exposed to methyl mercury. Thestudy showed that more cells die when theyare exposed to a mixture of DHA and methylmercury, rather than methyl mercury alone.The opposite was the case when the cellswere exposed to a mixture of EPA andmethyl mercury. The combination of theomega-6 fatty acid arachidonic acid andmethyl mercury had no effect on the numberof viable cells, compared to the cells thatwere only exposed to methyl mercury. Workis now in progess to establish whichbiological and genetic mechanisms areinvolved, in order to understand how EPAprotects the cells against the negative effectof methylmercury.


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One of the biggest healthchallenges facing the Westernworld today relates to poor diet(including too much saturated fatand sugar), in addition toinsufficient exercise. The WorldHealth Organisation (WHO) is veryconcerned with this developmentand has increased its focus on therapid growth of lifestyle diseases,which is also related to poornutritional status. Lifestyle diseasesinclude cardiovascular diseases,obesity, osteoporosis and mentaldisorders. The prevention of lifestylediseases through a healthier diet,

more physical activity and quittingsmoking will be highly prioritiseditem on the WHO agenda:Engaging for health. A globalhealth agenda (WHO). Populationsat large are generally advised toincrease the consumption of fishand other seafood, and betterdocumentation underpinning thebeneficial health effects of eatingseafood, will make an importantcontribution to achieving the goalof a higher intake of seafood.According to ”A comprehensiveassessment of fish and seafood inthe Norwegian diet” published by

the Norwegian ScientificCommittee for Food Safety, it is sofar mainly the positive effect ofmarine omega-3 on cardiovasculardiseases that has been sufficientlydocumented. This is largelybecause many studies havefocused, on cod liver oil or fish oil,and not on the fish itself. Seafoodcontains a unique combination ofnutrients; proteins, vitamins,minerals and marine omega-3 fattyacids, and NIFES conduct researchto understand the health effectsfrom consuming seafood.

Can seafood provide protection against lifestyle diseases?

“Populations at large are generally advised to increase the consumption of fish and otherseafood, and better documentation underpinning the beneficial health effects of eating seafoodwill make an important contribution to achieving the goal of a higher intake of seafood”

Obesity and diabetes

Fat combined with sugar orstarch plays a role in thedevelopment of obesity

The positive effects of fish oil on health arewell known, but presently the scientificdocumentation of the effects of fish oil onobesity is relatively limited. NIFES istherefore also engaged in research todetermine whether proteins, sugar and othertypes of carbohydrates affect thedevelopment of obesity when they areconsumed along with fish oil.

Previous feeding trials carried out at NIFEShave shown that mice which were given fishoil and sugar together became considerablymore obese than those which were given acombination of fish oil and large quantitiesof protein. The level of calories in the feedtypes was identical.

The institute has now carried out a

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corresponding feed trial where the mice weregiven either fructose or glucose incombination with fish oil in order todetermine whether the increase in weight wasrelated to one or the other of thesecarbohydrates.The mice which were given fish oil andglucose together put on weight, while thosethat were given fructose and fish oilaccumulated fat in the liver, which plays avital role in fat metabolism.

One other feed trial was carried out on mice.This time the mice were given fish oil alongwith two different kinds of starch, one with ahigh and one with a low glycemic index. Thecalorie content in both feed types wasidentical. Starch which is sugar, a type ofcarbohydrate, is found in a number of foodproducts. Processed types of starch have ahigh glycemic index and increase bloodsugar. The mice which were given fish oiland starch with a high glycemic indexbecame more obese than those which weregiven a mixture of starch with a lowglycemic index and fish oil in the feed.

The reason for the development of obesitymight be that the level of the hormoneinsulin rises when the mice eat differenttypes of carbohydrates. Insulin plays animportant role in the metabolism and storageof energy (mainly in the form of fat) in thebody. In order to investigate whether insulinproduction is instrumental in thedevelopment of obesity in mice, a feed trialis to be started which will be identical to thefeed trial where the mice were given acombination of fish oil and sucrose or fish oiland protein. But this time some of the micewill also be given a substance that inhibitsthe production of insulin.

In collaboration with: University ofCopenhagen, University of Bergen andBeijing Genome Institute.Funding: Research Council of Denmark.

Do mice get fatter from ayo-yo diet?

People who slim repeatedly by going on lowcalorie diets claim that they put on weightquicker and weigh more when they havecompleted the diet. To test whether this has aphysiological explanation, NIFES has beenstudying fat storage in mice which have beengiven a diet rich in sugar and fat, alternatingwith a low calorie diet over some time. Thefat storage in these mice was compared withmice which had received a continuous dietwith a high fat and sugar content. Despite thefact that the mice that had been on the yo-yodiet had eaten fewer overall calories than themice that ate the same diet over the entireperiod, both groups weighed exactly thesame. The ”yo-yo mice” probably producemore fat cells as a result of hunger, andNIFES will assess why this happens.

In collaboration with: University ofCopenhagen.Funding: Research Council of Denmark.

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Glycemic indexIt serves as a measure or ranking of foodsaccording to how fast and high the bloodsugar rises after a meal.

Proteins from marine sourcesand insulin resistance

A diet with too much fat increases the risk ofdeveloping insulin resistance. Insulinresistance can lead to type II diabetes. In aprevious study, NIFES showed thathydrolysed salmon proteins in the feed havea protective effect against obesity and insulinresistance in rats, and the Institute has nowstarted a study to determine how differenttypes of marine proteins affect insulinresistance in mice. In this study, the micewere given feed containing either proteinsfrom whale or salmon, or milk proteins.

In collaboration with: University ofCopenhagen and INSERM.Funding: Research Council of Norway.

Mental health

Can seafood help forpostnatal depression?

Previous studies have shown that there maybe a link between seafood in the diet andmental health. Postnatal depression affects10-15% of mothers in Norway.

The diet is important both before and aftergiving birth, but Norwegian women who areat a reproductive age and pregnant consumelittle seafood. At the same time, it is perhapsthese women who need it most, since theyare carrying a child whose nutrition comesfrom the mother.

NIFES will be carrying out a study todetermine how diet can affect both themental health of the mother during and afterpregnancy and the development of the childafter birth. The aim is to find out whethermore seafood in the diet can lead to a betternutritional status and fewer mental disordersamong mothers, and to study the significance

this can have for the child. We will also beexamining vitamin D, vitamin B12 and theiodine status of the pregnant women in boththe prenatal and postnatal period. These arenutrients that are important for the health ofboth the mother and the child. I In the lasttrimester of the pregnancy and in the perioduntil the infant is one year old we will keep arecord of the food that is eaten by the mother,the father and the child, and we will takebiological samples of both the mother andthe child. Recruitment to the project startedin autumn 2009.

In collaboration with: The regional centrefor the mental health of children andadolescents (Uni Helse/RBUP Vest) and theMunicipality of Fjell.Funding: Programme Board for Nutrition,University of Bergen and Ministry ofFisheries and Coastal Affairs.

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“The diet is important bothbefore and after giving birth,but Norwegian women whoare at a reproductive ageand pregnant consume littleseafood”

Cardiovasculardiseases

Eating salmon reduces therisk of cardiovasculardisease

Many studies have confirmed the positiveeffect of a supplement of marine omega-3fatty acids in people suffering fromcardiovascular diseases. This knowledge iswell established, but in most of these studiesfish oil capsules have been used. NIFES istherefore studying how marine omega-3 fattyacids from fish affect this group of people.

In 2008 NIFES finished an eating trial whereChinese men participated at risk fordeveloping cardiovascular/lifestyle diseases.The aim was to study how fatty fish affectsthe risk of developing cardiovascular/lifestylediseases in high risk groups. The result fromthis study showed that consuming salmonwhich is rich in omega-3 and other importantnutrients had a positive effect on the

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participants’ health parameters. In 2009 theInstitute started recruiting Chinese womenfor a corresponding eating trial.

In collaboration with: Institute for Nutritionand Food Safety, Beijing, China.Funding: Research Council of Norway,Norwegian Seafood Export Council,Ministry of Fisheries and Coastal Affairs.

Back and joint pains

Do marine oils help againstback pains?

Muscular and skeletal pains are commonamong the public at large, accounting for halfof the cases of long-term sick leave inNorway.

NIFES studies how cognitive treatment ordietary supplements affect patients who areon sick leave due to chronic lower back pains(www.cins.no). The aim is to get the patientsback to work, and to examine painalleviation.

All of the patients will receive short-termcognitive specialist treatment that isstandardised and quality-assured. Thetreatment includes thorough medicalexaminations, advice on physical activity and

how to come to terms with the complaints.The patients will then be split into fourdifferent groups. One group of patients willreceive no further supplementary treatment.The patients in group two will receive alonger course of behavioural therapy focusedon thought and behaviour patterns related tothe back pains. The last two groups will get adiet supplement in the form of capsules,either seal oil, which has been shown toreduce pain, or soy oil for control purposes,and administered on a double blind basiswhere neither patient nor the doctor knowwhat has been given. Blood samples will beanalysed for different fatty acids and the datawill be compared with information about thepatients’ consumption of seafood.

In collaboration with: Uni Helse,University of Bergen, and clinics/hospitalsin various parts of Norway.Funding: Ministry of Fisheries and CoastalAffairs.

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“NIFES studies how cognitive treatment or dietarysupplements affect patients who are on sick leavedue to chronic lower back pains”

Whale and seal oil alleviatejoint pains

Joint pains due to inflammatory boweldisease (IBD) are often difficult to treat asthe medicines normally used for joint painsmay make IBD worse. Marine oils are rich inthe fatty acid EPA which has an anti-inflammatory effect.

Under a study carried out at NIFES, 18patients were given seal or whale oil for 10days. The oil was administered directly intothe small intestine where the inflammation islocalised. Both groups experienced areduction in the pain and a better quality oflife after taking the oil. The results alsoshowed that the patients who had been givenseal oil had a lower level of PEG2, which isa biomarker for inflammation and pain, afterthey had taken the oil for 10 days. This wasnot equally clear, however, in the patientgroup which had been given whale oil,possible because the level of EPA in whaleoil is lower than in seal oil. The results are inline with findings from studies where

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patients have been drinking fish oil for 14days.

As both seal oil and whale oil contain lessmarine omega-3 fatty acids, it is thereforepossible that there are also other componentsin whale and seal oil which contribute to thepositive effect.

In collaboration with: HaukelandUniversity Hospital, University of Bergen.Funding: University of Bergen, HaukelandUniversity Hospital, Fishery and AquacultureIndustry Research Fund, Ministry of Fisheriesand Coastal Affairs.

Oxidised omega-3 products– do they affect our health?

In a project funded by the Food ResearchProgramme, of the Research Council ofNorway, NIFES will examine whether thereare negative health effects associated witheating rancid fish oil. It seems obvious thatfresh fish oil is healthier than rancid fish oil,but the effects are not well documented. Both

consumers, the government and the industryare interested to know more about howomega-3 from different products may beabsorbed in the body and which criteriashould be followed with respect to freshness.The studies will make use of cellexperiments, animal experiments and humaneating trials.

In collaboration with: University of Oslo,University of Uppsala.Funding: Research Council of Norway,Ministry of Fisheries and Coastal Affairs,Smartfish AS, Marine Harvest Ingredients.

Bone health

Vitamin D in fish fillet –what is its significance forbone health?

Throughout life, the calcium in our bones isconstantly replaced. When less calciumreplaces the calcium that is lost, our bonesbecome weaker and more brittle and we aremore exposed to fractures. Persons with theearly symptoms of osteoporosis are advisedto take a calcium and vitamin D supplement.Fatty fish and fish liver, as well as someother seafoods, are the only natural sourcesof vitamin D in our diet.

Vitamin D increases the absorption ofcalcium in the intestine and is necessary toregulate the body’s calcium balance. VitaminK appears to ensure that calcium is taken upin the bone tissue. NIFES has producedsalmon enriched with vitamins D and Kwhich has been used in an eating trialinvolving women in the menopause who areespecially susceptible to osteoporosis. In the

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salmon, vitamin D is converted into activemetabolites, and the aim of the trial is to seeif vitamin D and vitamin D metabolites havea better effect on bone health when they aretaken up through the salmon rather than whenvitamin D is taken in pill form.Three groups made up of 123 participants inall were given salmon with different levels ofvitamins D and K, while one group wasgiven vitamin D and calcium as a dietsupplement. The amount of vitamin D andK was measured before and after theconsumption of salmon or the supplementin order to determine whether the enrichedsalmon had an effect on the women’svitamin status. The bone metabolism rate(the rate at which calcium is replaced inbone) was also measured. The resultsindicate that there is a differencebetween the different groups, but it isstill too early to state the cause of thedifference.In collaboration with: Skretting, Universityof Bergen (Haukeland University Hospital).Funding: Research Council of Norway,Ministry of Fisheries and Coastal Affairs.

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Search yourself!

Do you want to know the content ofenvironmental pollutants andnutrients in Norwegian commercialfish species? Take a look at thesearchable database onwww.nifes.no/seafood

Fourteen countries with a total of 33 partners haveparticipated in the four-year project Aquamax,which is headed by NIFES. The full name of theproject is ”Sustainable AquaFeeds to Maximise theHealth Benefits of Farmed Fish for Consumers”and it will be concluded in 2010. The project isintegrated in the EU’s 6th Framework Programme,and the countries participating which are outsidethe EU are Norway, India and China. The projecthas an overall cost framework of € 15 million.

Aquamax has provided the opportunity to preparevarious tailor-made feeds using alternative rawmaterials for farmed salmon, rainbow trout, seabass, sea bream and carp. The aim has been toarrive at a plant based feed which is good for boththe fish and the consumers. A number of trialshave been carried out, covering the entire valuechain from the fjord to the dinner table. Theresearch has resulted in important new knowledgeabout the nutritional needs of the fish, and aboutfish as safe and health food.

Cholesterol in salmon is reduced by plantraw materials in the feedThis project has shown that it is possible to replace

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Research News from NIFES Aquamax

70% of the fish oil and 80% of the marineproteins in traditional salmon feed by plantraw materials without this being at theexpense of the salmon’s nutritionalrequirements. The level of nutrients in plantbased raw materials and marine rawmaterials differ, but there are also othercomponents in plant raw materials whichmay affect fish health. Various animalmodels have also shown that certaincomponents in plants affect the level ofcholesterol in the blood, and among these arephytosteroles which have the effect ofreducing cholesterol in humans. The projectshowed that the level of phytosteroles in thesalmon’s blood increased as the proportion ofplants in the feed increased, and the level ofcholesterol in the salmon’s blood fell as theamount of plants in the feed was increased.

However, as the level of phytosteroles in thefillet was relatively low, the level ofcholesterol in the consumer will not beaffected to any appreciable extent by eatingsalmon fed on plant-based feed.

High cholesterol is a risk factor forcardiovascular diseases in humans, andNIFES will now do research to determinehow phytosteroles affect heart health insalmon. This is part of a new project aimedat analysing heart health and obesity, in bothsalmon given plant-based feed, and inhumans who consume this salmon.

Lower level of heavy metals, PCB,dioxins and bromated flameretardantsSeveral environmental pollutants degradevery slowly and accumulate in livingorganisms. These substances are also foundin fish and other seafood. Marine feedproducts contain more organic environmentalcontaminants such as PCB, dioxins andbrominated flame retardants, also calledPersistent Organic Pollutants (POPs), than

plant raw materials. These substances are fat-soluble and are found in fish oil. Fish mealsare a potential source of heavy metals.However, plant raw materials may alsocontain other undesirable substances whichare not found in marine raw materials.

NIFES has examined the transfer of differentundesirable sustances from feed to fish in theentire production cycle for salmon whichwere given a traditional marine based feed,or a feed containing 70% plant oils and 80%plant protein. It was found that using plantraw materials reduced the content of POPs insalmon fillet by 51 – 82%, while the level ofarsenic and mercury fell by 80 – 90%.However, the level of polyaromatichydrocarbons (PAH) was significantly higherin the fillet from salmon that had been givenplant-based feed compared with salmon thathad consumed a feed containing marine rawmaterials. The results show that the use ofplant based raw materials in the feed reducesthe level of POPs in the fillet, but canincrease the level of undesirable substancessuch as PAH which are found in plants.

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“The research has resulted inimportant new knowledgeabout the nutritional require-ment of the fish, and aboutfish as safe and health food”

Do women who eat fish havechildren who are free of allergicconditions?A steadily increasing number of childrendevelop atopic eczema, asthma and other

allergic conditions. Several scientific studiesindicate that this is connected to a lowomega-3 status among women duringpregnancy. There is therefore reason tobelieve that the development of allergies hasalready started before the child is born.

Under the Aquamax project pregnant womenin the UK were given salmon for dinnertwice a week, from the 21st week ofpregnancy until birth takes place. Salmoncontains especially low levels ofenvironmental contaminants such as POPs

and heavy metals, and more than enoughomega-3 fatty acids to ensure thatthe women receive an amountcorresponding to ISSFAL’srecommended weekly intake ofomega-3. The results so farindicate that the intake of salmonhas had a good effect on thewomen’s general nutritional status,and that both mother and childhave an improved omega-3 status.This confirms that a healthy andvaried diet is important for themother’s nutritional status. It isstill too early to say whether thewomen’s intake of salmon has anyeffect on the development ofatopic eczema in the children.

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Programme 1: Sustainable feedThis programme aims to develop novel aquafeeds enabling theproduction of healthy and contaminant free: carpe, rainbow trout,Atlantic salmon and seabream.

Programme 2: Health benefitsThis programme will assess the human health benefits of fish producedon new feeds.

Programme 3: Seafood safetyThis programme will assess the safety of fish farmed on the newfeeds.

Programme 4: Public perceptionThis programme will assess public perception of farmed fish anddevise a framework to communicate the risk and benefits of consumingfarmed fish to the public and other other stakeholders.

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ht tp://www.aquamaxip.eu

- Norway- China- France- Sweden- Spain- Italy- United Kingdom

- Estonia- Greece- Netherland- Hungary- Germany- India- Belgium

The tropical island of Mauritius inthe Indian Ocean wants to increaseits fish farming activities. NIFES isproviding competence to aidMauritius in establishingappropriate legislation andmonitoring of both fish, feed andmedication. In 2008 NORADinitiated a 3-year programme ofcollaboration between Norway andMauritius. The aim of the project isa transfer of competence in themanagement of fisheries and fishfarming activities.

By participating in workingmeetings and providing guidance,NIFES has helped to enhance thelevel of public management inMauritius and to establishmonitoring systems for the island’sfish farming activities. This includesthe production of fish feed, the useof medication and control ofresidual medication in fish. At aworking meeting held in May 2009

the agenda included fish nutrition,feed resources and feed regulations.

At a new meeting in January 2010the focus was on laboratory controlof feed, quality assurance, sampling,reviews of international regulationsand the introduction of nationalregulations for the use ofmedication and controls inMauritius.

In collaboration with: Centre forDevelopment Cooperation inFisheries (CDCF), Institute ofMarine Research, Directorate ofFisheries and Ministry of AgriIndustry and Fisheries (MAIF) onMauritius.Funding: NORAD.

NORAD collaboration project

Collaborators from:

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NIFES: A nationalreference laboratory

NIFES is accredited in accordance with theISO-NS-17025 standard, and complies withobligations set under the EEA Agreementpursuant to its status as a national referencelaboratory (NRL) for the determination ofpollutants, nutrients and microbiologicalcontent in accordance with the followingdirectives:

Dir. 96/23EC – Measures to monitorsubstances and residues (only in aquacultureproducts), Dir. 92/117/EEC – Monitoring ofzoonoses and zoonotic agents (only parasitesin marine organisms), Dir. 01/492 and 79/023– Blue mussel directive, Dir. 2002/32/EC of7 May 2002 – Undesirable substances infeed, Regulations 1831/2003 – Foodadditives (only for fish feed), CommissionRegulation 466/2001 – Limit values forcontaminants in food.

The obligations which NIFES has as NRL isrelated to Control Regulation 882/2004, art.33 and include cooperation with the

Community Reference Laboratory (CRL). Ifthere are several national referencelaboratories (NRL) in an area, they arerequired to cooperate.

As a national reference laboratory, NIFEShas a responsibility to arrange nationallaboratory tests, analyse random samplesfrom accredited laboratories, giveprofessional advice and guidance within thereference function area, give advice aboutaccreditation of analyses and engage inmethod development and method adjustment.The laboratory is also required to be updatedon the international development of methodswithin the reference function area.

Renewed accreditationstatus for NIFES

NIFES determines nutrients and undesirablesubstances in foodstuffs, mainly fish andother seafood, for the Norwegian authorities.Based on these data and research in the fieldsof aquaculture nutrition and human nutrition,seafood safety and surveillance, the Institute

gives advice to the public sector, the foodindustry and regulatory bodies as part of theprocess of ensuring that it is safe and healthyto eat seafood.

Norwegian accreditation is carried outannually, and every fifth year there is athorough review of the quality system at thelaboratories of NIFES. In 2009 the institutereceived renewal of its accreditation statusfor a further five years. This confirms thatthe activities of NIFES are in line withcurrent standards and that the internalprocedures at the laboratories ensuresatisfactory traceability and control of data.The methods are also tested regularly onringtests (interlaboraty proficiency test)which give an indication of how the methodsperform compared with correspondingmethods at external laboratories. Norwegianaccreditation requires that accreditedcompanies take part in ring tests.

NIFES currently has around 70 accreditedmethods of analysing different undesirablesubstances and nutrients in foodstuffs,including fish and seafood. NIFES also has a

Method development – undesirable substances and nutrients

number of accredited microbiologicalmethods of identifying parasites, residualmedication and bacteria in seafood andseafood products.

Method activity

A common method has been developed forthe collection of samples to be analysed fororganic environmental pollutants. Its area ofapplication includes PCB, dioxin-like PCB,dioxins and brominated flame retardants. Themethod makes analysis work more effective.

A common method has also been developedfor the collection of samples to be analysedfor pesticides. The method has been validatedand is used in routine analyses.

Several new methods have been developedfor the analysis of undesirable substances andmetals. This includes a new method ofanalysis for the minerals sodium, potassium,magnesium, calcium and phosphorus usingICPMS which has been developed and


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validated. The method can be used to analysefor all five minerals at the same time. Amethod of determining the level of methylmercury using isotope dilution GC-ICPMShas also been validated.

NIFES has started work on the developmentof more selective and sensitive analysismethods for residual medicines.

Steps are in hand to implement a newmethod for determining the presence ofmalachite green, crystal violet and brilliantgreen, as well as leukoforms of the two first-mentioned.

NIFES has developed a method that canquantify 18 different PFAS compounds(perfluorated organic compounds). PFAS hasbeen found in low concentrations in seafood.Several of them have not been found inseafood before.

Fish and shellfish can take up PAH(polyaromatic hydrocarbons), also in the caseof discharges from oil tankers. NIFES has

therefore been working on the developmentof an effective and automated method ofdetermining the different PAH compounds.

NIFES has developed a method foridentifying the fatty acid that is bound toglycerol in a specific position (position 2).The fatty acid can be identified in differentmarine oils, whale oils and seal oils. Themethod is automated and very effective.Research shows that it is the fatty acid inposition 2 that has the greatest nutritionalvalue.

Cell cultures are among the tools used tounderstand how individual nutrients affectfish and humans. It is a tool which reducesthe use of animal testing. NIFES hasdeveloped cell models which can be used tostudy the effects of different nutrients andundesirable substances on the immunesystem of salmon and cod.

NIFES already has a cell model system tostudy the effect of environmental pollutants

on the liver cells of salmon, but as differentspecies react differently to contaminants theInstitute has now developed a correspondingmodel system for liver cells from cod. Thishas not been done before.

In order to understand how omega-3 andomega-6 in the diet affect the body’sproduction of chemical messengers whichincrease or reduce inflammatory effects,there is a need to measure biomarkers indifferent cells and tissues. NIFES haspreviously developed a reproducible, rapidand simple method for identification of thebiomarker PGE-2 (eicosanoid) in cellscultivated in the laboratory. Furtherdevelopment work is being carried out onthis method so that it can also be used tomeasure biomarkers of this kind in othersample types.

Funding: Ministry of Fisheries and CoastalAffairs

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Aquaculture NutritionNIFES has editorial responsibility for thescientific journal ”Aquaculture Nutrition”, whichis published by Wiley-Blackwell. The journalreceives an increasing number of manuscripts tobe assessed for publication, particularly frommajor aquaculture nations like China, India andBrazil. Wiley-Blackwell has a new websitepresenting both the publishing house and thejournal, and the efficiency of the search enginehas been improved. The journal currently has onechief editor and three co-editors. The steadilyincreasing number ofarticles in the journal,and the need to increasethe number of pages,shows that”AquacultureNutrition” is aninternationallyrecognised journal inthe area of fishnutrition.

”Fiskesprell”The action plan for a better diet amongthe public at large (2007-2011)concluded, among other things, that theconsumption of seafood by Norwegiansis lower than it ideally should be, andchildren eat less fish than adults. It wasbecause of this that the “Fiskesprell”project was started. It’s aim is toincrease the focus of fish consumptionamong children and young people,partly by integrating this topic inteaching activities in nurseries and inthe Food & Health curriculum insecondary schools.

The project is administrated by theMinistry of health and Care Services,the Ministry of Fisheries and CoastalAffairs, and the Norwegian Directoratefor Health and Social Affairs, and isheaded by the Norwegian SeafoodExport Council. NIFES previously hadresponsibility for the nutritional aspects

of the project through the booklets”Fiskesprell for nursery personnel”,"Fiskesprell, a teacher’s guide for Food& Health in secondary schools" and"Fiskesprell, a study manual for the 9thand 10th grade”.

In 2009 the process of extending theproject to include primary schools wasstarted, and NIFES was responsible fordesigning the booklet “Fiskesprell, astudy manual for the 5th-7th grades”. Inconformity with the teaching plan, thecontents are divided into ”Food &Lifestyle”, ”Food & Consumption” and”Food & Culture”. The booklet can beused separately or as a supplement toother teaching material. Several of theexercises in the booklet can also beused in other subject areas. SinceFebruary 2010 the project has beenopen to primary schools throughoutNorway.

Teaching for the University of Bergen

Fish NutritionMAR 253(10 ECTS)

Seafood MicrobiologyMAR 255(10 ECTS)

Food Chemistry and AnalysisMAR 352(15 ECTS)

Food ToxicologyMAR 353(10 ECTS)

Macro - and micro nutrientsNUTR 207(10 ECTS)

Human Nutrition - MacronutrientsNUTR 300(10 ECTS)

Human Nutrition - Micro nutrientsNUTR 301(10 ECTS)

Human nutrition - DigestionNUTR 302(10 ECTS)

Human nutrition – Methods inNutrition AnalysisNUTR 310(5 ECTS)

The structure and function oflipidsHUCEL367A(5 ECTS)

Teaching and educationThe University of Bergen offers education atboth Master and PhD-level within aquaculturenutrition and human nutrition in collaborationwith NIFES. Six of NIFES’ academic staff wereaffiliated to the University of Bergen beingresponsible for teaching 10 subjects throughout2009. All together NIFES contributed withteaching in 13 subjects, giving about 90 credits.

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The National Institute of Nutrition and SeafoodResearch (NIFES) is a research institute withadministrative duties, affiliated to the Norwegian Ministryof Fisheries and Coastal Affairs. The institute givesresearch-based advice to the government, food authoritiesand the aquaculture- and fishery industries in mattersconcerning fishfeed, health and safety aspects of seafood

consumption. The Institute is independent and publishes theresults of its research nationally and internationally.

NIFES has modern laboratory facilities including alaboratory for nutrient analysis, a laboratory for analysingundesirable substances and a molecular biologylaboratory. The institute functions as a national referencelaboratory for a number of methods and has approx. 70accredited methods in accordance with Norwegianstandard NS-EN ISO/IEC 17025.

In collaboration with NIFES, the University of Bergen offerseducation at bachelor- master- and PhD levels in the fieldsof human nutrition and fish nutrition. In addition, NIFEShosts apprentices in laboratory work.

NIFES holds the editorial responsibility for the internationalperiodical Aquaculture Nutrition.

Research at NIFES is divided into four programmes:

• Seafood and Health• Seafood Safety• Aquaculture Nutrition• Surveillance

More information onwww.nifes.no

NIFESP.O. Box 2029 Nordnes,5817 BergenNorway

Telephone: +47 55 90 51 00Fax: +47 55 90 52 99E-mail: [email protected]

Visiting address:Strandgaten 229, 5004 Bergen, Norway

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Research news 2010