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A. Kungolos1, V. Tsiridis2, M. Petala2, C. Emmanouil1, S. Kipouros1, D. Antoniadis3, G. Drakopoulos3, P. Dimakos1 and
K. Perakis1
1Department of Planning and Regional Development, University of Thessaly, 38334 Volos, Greece
2Department of Civil Engineering, Aristotle University of Thessaloniki, 54006, Thessaloniki, Greece
3NGO Epidro, Massalias 16, 10680 Athens, Greece
Ecotoxicological assays as a means of monitoring vulnerable aquatic ecosystems
How to determine the hazard resulting from pollution?
Chemical approach Chemical analyses of the pollutants
Biomonitoring
Bioassays: effects of chemicals, natural waters, pollutants, wastes,…on aquatic and terrestrial living organisms
Why do we need Monitoring?
Water quality may be affected by: Spills of oil and industrial products from tanks, pipelines
Pesticides from agricultural area, leaching pathogens
Endocrine disrupting chemicals
Neurotoxins, hepatotoxins from algae blooms
Contamination from terrorist attack (toxins, microbes, viruses, radioactive compounds)
Accidents, sabotage etc.
Why do we need Biomonitoring?
It is impossible to analyze all chemical substances, which are brought into nature by human
Scientists suggest that there are more than 100 000 harmful chemicals
Even with the most advanced instruments it is not yet possible to detect them all
With the help of biomonitoring, a much broader view of the possible dangerous effects can be detected
Toxicity testing used in our Lab in the University of Thessaly, Greece
15 min inhibition test of the photobacterium Vibrio fischeri
72 h growth inhibition test of the microalae Pseudokirchneriella subcapitata
24 or 48 h immobilization test of the crustacean Daphnia magna
Normal bioluminescence
Contaminated sample is added!!
Bioluminescence inhibition
Photobacterium Vibrio fischeri (Microtox test)
Photobacterium Vibrio fischeri
Bioluminescence measurement at exposure time 5, 15 and 30 minMicrotox M500 analyzer
Microalgae Pseudokirchneriella subcapitata(Algaltoxkit F)
Immobilized algae
mobilization
Measurement of the optical density (at 670 nm) after 72 h
Crustacean Daphnia magna (Daphtoxkit F magna)
Measurement of the immobilized/dead organisms
Addition of the samples and live organisms in multiwell test plate
Exposure for 24 h at 20 oC
Hatching of the ephippia
Toxicity tests have been used for:
Marine and fresh waters biomonitoring
Toxicity testing of wastewaters and soils
Toxicity testing of fly ash leachates
Toxicity assessments of pure compounds, heavy metals and
pesticides
Wastewater treatment plant applications
Applications of ecotoxicity testing
Correlation between the toxicity of lignite fly ash leachates towards D. magna and the concentration of Cr(VI) detected in the leachates
Correlation coefficient, r= 0.961Level of significance, p<0.01
Investigation of the interactive toxic effects of chemicals on live test organisms
MODE OF INTERACTION
•Additive if there is no significant difference between expected and observed effect
• Synergistic if the observed effect is significantly higher
• Antagonistic if the observed effect is significantly lower
Expected and observed effects
Expectedby a model based on the theory of probabilities
P(E) = P1 + P2 – P1P2/100
where P(E): the theoretically expected additive effect of a binary chemical mixture
Pi : the effect caused by a certain concentration of a
chemical when it acts alone
ObservedThe measured effect of the binary chemical mixture
Combined effect of Cu2+ and Zn2+ on V. fischeri(Synergistic effect)
0
20
40
60
80
100
A B C D E F G
Concentration combinations
Effe
ct,
%
Expected
Observed
Cu2+ Zn2+ (mg/L) (mg/L)A: 0.117 0.432B: 0.117 0.864C: 0.117 1.727D: 0.168 1.727E: 0.252 0.432F: 0.252 0.864G: 0.252 1.727
Comparison between theoretically expected and observed immobilization for the combined effect of metalaxyl-M and copper on D. magna
(antagonistic action)
0
20
40
60
80
100
A B C D E F
Concentration combinations
Imm
obil
izat
ion
, %
ExpectedObserved
Metalaxyl-M Cu (mg/L) (mg/L) A: 10 0.05 B: 10 0.10 C: 30 0.05 D: 30 0.10 E: 60 0.05 F: 60 0.10
Current project on ecotoxicity testing
Ecotoxicity testing of selected lake waters and treated wastewater effluents
- Lakes Koronia and Karla- Treated wastewater efluents from Tyrnavos region
- Ecotoxicity testing using the photobacterium Vibrio fischeri, the crustacean Daphnia magna and the algae Pseudokirchneriella subcapitata
The research is funded by Ministry of Environment, Energy and Climatic Change/Green Fund programme: Environmental Research-Innovation- National Cooperations 2012”: “Improvement of monitoring water quality with the use of ecotoxicological assays”
The only way to get an “integrated” answer to the hazard caused by pollutants to the environment, is to expose organisms of the receiving environment to these pollutants
Chemical analyses Bioassays Environmental
Hazard Assessment
+ =
Chemical analysis in many cases deals with a restricted number of compounds due to financial and technical limitations
For a “real hazard” monitoring, phenomena such as bioavailability, synergistic or antagonistic effects on the biota have to be examined
A single toxicity test does not tell whether other important groups of biota are affected by exposure to the same samples. It is thus necessary to use a battery of tests with species representative of the different links in the trophic chains
SECOTOX 2013 & CEMEPE Conference(Conference on Environmental Management, Engineering,
Planning and Economics)
Myconos, June 24 – 28, 2013
THANK YOU FOR YOUR ATTENTION!
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