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Pesticides Pro and ConPesticides Pro and Con Kill unwanted pests that Kill unwanted pests that
carry disease (rats, carry disease (rats, mosquitoes, Tse-Tse mosquitoes, Tse-Tse flies)flies)
Increase food suppliesIncrease food supplies More food means food is More food means food is
less expensiveless expensive Effective and fast-actingEffective and fast-acting Newer pesticides are Newer pesticides are
safer, more specific safer, more specific Reduces labor costs on Reduces labor costs on
farmsfarms Food looks betterFood looks better Agriculture is more Agriculture is more
profitableprofitable
Accumulate in food chainAccumulate in food chain Pests develop resistance – Pests develop resistance –
500 species so far500 species so far Resistance creates Resistance creates
pesticide treadmillpesticide treadmill Estimates are $5-10 in Estimates are $5-10 in
damage done for $1 spent damage done for $1 spent on pesticideon pesticide
Pesticide runoffPesticide runoff Destroy bees - $200 Destroy bees - $200
millionmillion Threaten endangered Threaten endangered
speciesspecies Affect egg shell of birdsAffect egg shell of birds 5% actually reach pest5% actually reach pest ~20,000~20,000 human human
deaths/yeardeaths/year
Types of PesticidesTypes of Pesticides Biological – Ladybugs, parasitic wasps, etc.Biological – Ladybugs, parasitic wasps, etc. Carbamates effect nervous system of pests Carbamates effect nervous system of pests
more water soluble than chlorinated more water soluble than chlorinated hydrocarbonshydrocarbons– Aldicarb, aminocarb, carbaryl (Sevin), Aldicarb, aminocarb, carbaryl (Sevin),
carbofuran, Mirexcarbofuran, Mirex Chlorinated Hydrocarbons affect nervous Chlorinated Hydrocarbons affect nervous
system –system –– Aldrin, Chlordane, DDT, dieldrin, lindane and Aldrin, Chlordane, DDT, dieldrin, lindane and
paradichlorobenzeneparadichlorobenzene Fumigants are used to sterilize soil and Fumigants are used to sterilize soil and
prevent grain infestationprevent grain infestation
Types of PesticidesTypes of Pesticides Inorganic – arsenic, copper, lead, Inorganic – arsenic, copper, lead,
mercurymercury– Highly toxic and bioaccumulation Highly toxic and bioaccumulation
Organic or natural – derived from Organic or natural – derived from plants such as tobacco and plants such as tobacco and chrysanthemumchrysanthemum
Organophosphates – extremely toxic, Organophosphates – extremely toxic, low persistencelow persistence– Malathion, parthion, chlophyrifos, Malathion, parthion, chlophyrifos,
acepate, propetamphos and trichlofonacepate, propetamphos and trichlofon
Chlorinated HydrocarbonsChlorinated Hydrocarbons
DDTDDT Affect the nervous system of pestAffect the nervous system of pest Remain in ecosystem 15+ yearsRemain in ecosystem 15+ years
CarbamatesCarbamates Carbamates effect nervous system of Carbamates effect nervous system of
pestspests More water soluble than chlorinated More water soluble than chlorinated
hydrocarbons – which means greater hydrocarbons – which means greater risks of dissolving in surface water or risks of dissolving in surface water or percolating into groundwaterpercolating into groundwater
100 grams has the same effect as 100 grams has the same effect as 2,000 grams chlorinated hydrocarbons2,000 grams chlorinated hydrocarbons
Examples: Aldicarb, aminocarb, Examples: Aldicarb, aminocarb, carbaryl (Sevin), carbofuran, Mirexcarbaryl (Sevin), carbofuran, Mirex
AldicarbAldicarb
Potato growers on eastern Long Island used Potato growers on eastern Long Island used Aldicarb from 1975 – 1979 to control the Aldicarb from 1975 – 1979 to control the Colorado potato beetle and the golden Colorado potato beetle and the golden nematode. In 1979, Aldicarb residues were nematode. In 1979, Aldicarb residues were detected in well water. Subsequent testing detected in well water. Subsequent testing found more than 2,000 wells with very high found more than 2,000 wells with very high concentrations. It was banned in New York.concentrations. It was banned in New York.
In 1984 areas with deep wells were found to have In 1984 areas with deep wells were found to have increased levels from 1979 levels. 1400 wells increased levels from 1979 levels. 1400 wells are still contaminated above state guidelines.are still contaminated above state guidelines.
Aldicard has been found in groundwater in 26 Aldicard has been found in groundwater in 26 other states.other states.
FumigantsFumigantsGaseous pesticides use Gaseous pesticides use
to sterilize soil and to sterilize soil and prevent pest prevent pest infestation of stored infestation of stored grains.grains.
Used on grain weevils, Used on grain weevils, beetles and moth beetles and moth catepillars.catepillars.
Comparable to “mustard Comparable to “mustard gases” used in WWII.gases” used in WWII.
Phosphine is the most Phosphine is the most popular today – others popular today – others were tied to were tied to contaminated (toxic) contaminated (toxic) bread and grain bread and grain products.products.
Methyl Bromide was banned in 2005 due to it’s damage to the ozone layer.
InorganicInorganic
Broad-based pesticides.Broad-based pesticides.
Includes arsenic, copper, lead, mercury.Includes arsenic, copper, lead, mercury.
Highly toxic and accumulates in the Highly toxic and accumulates in the environment.environment.
Organic or Natural PesticidesOrganic or Natural PesticidesNatural poisons derived from plants Natural poisons derived from plants
such as tobacco or chrysanthemum.such as tobacco or chrysanthemum.NeemNeem Ingredients:Ingredients: Contains 2 ingredients, azadirachtin Contains 2 ingredients, azadirachtin
(AZA0 and liminoids, both from the seed kernels of the (AZA0 and liminoids, both from the seed kernels of the neem tree fruit. neem tree fruit.
Application:Application: Sprayed onto plant leaves. Sprayed onto plant leaves. How It Works:How It Works: Upsets the insects hormonal system Upsets the insects hormonal system
and prevents it from developing to its mature stage. and prevents it from developing to its mature stage. Most effective on immature insects and species that Most effective on immature insects and species that undergo complete metamorphosis. undergo complete metamorphosis.
Pros:Pros: Non-toxic to humans Non-toxic to humans Cons:Cons: Washes away in rain. Slow acting. Breaks down Washes away in rain. Slow acting. Breaks down
in sunlight Indiscriminate pesticide in sunlight Indiscriminate pesticide Precautions:Precautions: Keep pets from treated leaves until they Keep pets from treated leaves until they
dry. dry.
Organic PesticidesOrganic Pesticides
PyrethrinsPyrethrins Ingredients:Ingredients: Derived from Derived from Chrysanthemum Chrysanthemum
cinerariifoliumcinerariifolium Application:Application: Generally found in powder form Generally found in powder form
and dusted on leaves. and dusted on leaves. How It Works:How It Works: Poisons the insect, causing a Poisons the insect, causing a
quick death quick death Pros:Pros: Quick acting. Low toxicity to animals. Quick acting. Low toxicity to animals.
Degrades within a day. Degrades within a day. Cons:Cons: Broad spectrum insecticide. Kills any Broad spectrum insecticide. Kills any
insect. Very toxic to honeybees insect. Very toxic to honeybees Precautions:Precautions: Use cautiously, only when you Use cautiously, only when you
have a major problem with hard-to-kill insects. have a major problem with hard-to-kill insects.
Organic or Natural PesticidesOrganic or Natural Pesticides
RotenoneRotenone Ingredients:Ingredients: Derived from the roots of Derived from the roots of
tropical legumes tropical legumes Application:Application: Dust onto plant Dust onto plant How It Works:How It Works: Inhibits a cellular process, Inhibits a cellular process,
depriving insects of oxygen in their tissue cells. depriving insects of oxygen in their tissue cells. Pros:Pros: Low residual effect. Breaks down quickly Low residual effect. Breaks down quickly
in sunlight. in sunlight. Cons:Cons: Broad spectrum pesticide Broad spectrum pesticide Precautions:Precautions: Apply in the evening, when bees Apply in the evening, when bees
are less active. are less active.
OrganophosphatesOrganophosphates
Malathion and ParthionMalathion and Parthion Extremely toxic but only remains in Extremely toxic but only remains in
the environment for a brief amount the environment for a brief amount of time.of time.
Effects the central nervous system Effects the central nervous system by interfering with the enzyme by interfering with the enzyme cholinesterase.cholinesterase.
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