Environmental Effects of Pesticides Environmental Effects of Pesticides Photograph by Ken Hammond. Stephen J. Toth, Jr. Wayne G. Buhler Department of EntomologyDepartment

EnvironmentalEffects of Pesticides

EnvironmentalEffects of Pesticides

Photograph by Ken Hammond.

Stephen J. Toth, Jr. Wayne G. BuhlerDepartment of Entomology Department of Horticultural ScienceNorth Carolina State University North Carolina State University

Erwin W. Cole

What is theWhat is theEnvironmentEnvironment

?? The “environment” The “environment”

is everything is everything around us natural around us natural and manmade; not and manmade; not limited to the limited to the outdoors, but outdoors, but including indoor including indoor areas in which we areas in which we live and work.live and work.

Ken Hammond

How do Pesticides EffectHow do Pesticides Effectthe Environment?the Environment?

Point-Source PollutionPoint-Source Pollution: contamination that : contamination that comes from a specific, identifiable place (a comes from a specific, identifiable place (a point)point)

Includes pesticide Includes pesticide spills, wash water spills, wash water from cleanup sites, from cleanup sites, leaks from leaks from storage storage sites, and improper sites, and improper disposal of pesticides disposal of pesticides and their containers and their containers

Tim McCabe

How do Pesticides EffectHow do Pesticides Effectthe Environment?the Environment?

Nonpoint-Source PollutionNonpoint-Source Pollution: : contamination that comes contamination that comes from a wide area from a wide area

Includes the drift of Includes the drift of pesticides through pesticides through the air, pesticide run- the air, pesticide run- off off into waterways, into waterways, pesticide movement pesticide movement into ground water, etc. into ground water, etc.

Bob Nichols

Environmentally-Sensitive AreasEnvironmentally-Sensitive Areas

areas where ground areas where ground water is near surface water is near surface or easily accessed or easily accessed through wells, through wells, sinkholes, etc.sinkholes, etc.

areas near surface areas near surface waters (oceans, waters (oceans, lakes, streams)lakes, streams)

Sensitive areas include sites or living things that are easily injured by pesticides, including:

NCSU Communication Services

Environmentally-Sensitive Environmentally-Sensitive AreasAreas

areas heavily areas heavily populated with people populated with people (schools, playgrounds, (schools, playgrounds, hospitals, nursing hospitals, nursing homes, etc.)homes, etc.)

areas populated with areas populated with livestock and petslivestock and pets


Ken Hammond

Environmentally-Environmentally-Sensitive AreasSensitive Areas

areas near the habitats areas near the habitats of endangered species of endangered species and other wildlifeand other wildlife

areas near honey beesareas near honey bees areas near food crops areas near food crops

and ornamental plantsand ornamental plants


Steve Bambara

Environmental Impact of Environmental Impact of Pesticides in AirPesticides in Air

The atmosphere is an important part of the hydrologic cycleThe atmosphere is an important part of the hydrologic cycle Pesticides enter the Pesticides enter the

atmosphere through atmosphere through drift, wind erosion drift, wind erosion and and

evaporationevaporation Pesticides can move Pesticides can move

great distances in the great distances in the atmosphere atmosphere

Pesticides reach the Pesticides reach the earth’s surface via earth’s surface via dry deposition and dry deposition and precipitationprecipitation

U. S Geological Survey


DDT and other organochlorine pesticides DDT and other organochlorine pesticides detected in Arctic and Antarctic fish and detected in Arctic and Antarctic fish and mammals; used in 1960s and 1970s mammals; used in 1960s and 1970s

Toxaphene is still transported Toxaphene is still transported into Great Lakes region by into Great Lakes region by winds from the Gulf of winds from the Gulf of Mexico; used on cotton in Mexico; used on cotton in the South, banned in the South, banned in 1982 1982

USDA/ARS

Long-range movement of long-lived pesticides documented:


Organochlorine insecticides (DDT, dieldrin and Organochlorine insecticides (DDT, dieldrin and lindane): widespread use in 1960s and 1970s; lindane): widespread use in 1960s and 1970s; resistant to environmental degradationresistant to environmental degradation

Organophosphate insecticides (chlorpyrifos, Organophosphate insecticides (chlorpyrifos, diazinon, malathion and methyl parathion): diazinon, malathion and methyl parathion): not long-lived in environment; used heavily in not long-lived in environment; used heavily in the past and at presentthe past and at present

Triazine herbicides (atrazine): heavily-used Triazine herbicides (atrazine): heavily-used herbicides, persistant in environment herbicides, persistant in environment

Acetanilide herbicides (alachlor and Acetanilide herbicides (alachlor and metolachlor): used heavily, but not as metolachlor): used heavily, but not as persistant as triazine herbicidespersistant as triazine herbicides

Pesticides frequently detected in the atmosphere:


Number of pesticides detected in air, rain, snow and fog. U. S. Geologic Survey (1995).


Source of exposure to pesticides Source of exposure to pesticides through inhalation (lungs have through inhalation (lungs have surface area equal to tennis court)surface area equal to tennis court)

Source of contamination of surface Source of contamination of surface waters and ground water through waters and ground water through dry deposition and precipitationdry deposition and precipitation

Transport of pesticides from Transport of pesticides from application sites to sensitive areasapplication sites to sensitive areas

Accumulation of pesticides in the Accumulation of pesticides in the environment (soil, wildlife, etc.)environment (soil, wildlife, etc.)

Gene Alexander

Hazards of atmospheric pesticides to humans and environment:

Environmental Impact of Environmental Impact of Pesticides in SoilPesticides in Soil

Pesticides can move in the environment via Pesticides can move in the environment via the soil by two methods: erosion and leachingthe soil by two methods: erosion and leaching

ErosionErosion: soil particles : soil particles which are transported which are transported by wind and water; by wind and water; pesticides pesticides attached attached to soil particles to soil particles

LeachingLeaching: downward : downward movement of pesticides movement of pesticides in the soil through in the soil through cracks and pores cracks and pores

USDA Photograph

Environmental Impact of Pesticides in Environmental Impact of Pesticides in SoilSoil

LeachingLeaching Soil normally filters water Soil normally filters water

as it moves downward, as it moves downward, removing contaminants removing contaminants such as pesticidessuch as pesticides

Soil and pesticide Soil and pesticide properties, geography and properties, geography and weather can influence the weather can influence the movement of pesticides movement of pesticides (leaching)(leaching)

Pesticides that leach Pesticides that leach through soils may reach through soils may reach ground waterground water

USDA Photograph


Soil Properties That Affect LeachingSoil Properties That Affect Leaching Organic matterOrganic matter: plant and : plant and

animal material animal material decomposing in the soil; decomposing in the soil; organic matter binds organic matter binds pesticides; the more organic pesticides; the more organic matter in the soil, the less matter in the soil, the less likely pesticides will leachlikely pesticides will leach

Soil textureSoil texture: determined by : determined by the percentage of sand, silt the percentage of sand, silt and clay; the higher and clay; the higher percentage of sand, the percentage of sand, the more likely pesticides will more likely pesticides will leachleach

USDA Photograph


Soil Properties That Affect LeachingSoil Properties That Affect Leaching

Soil aciditySoil acidity ( (pHpH): the ): the acidity of the soil affects acidity of the soil affects chemical properties of chemical properties of pesticides; as the soil pesticides; as the soil pH decreases (becomes pH decreases (becomes more acidic), pesticides more acidic), pesticides bind more to the clay bind more to the clay in the soil making the in the soil making the pesticides less likely to pesticides less likely to reach the ground waterreach the ground water

Scott Bauer


Pesticide Properties That Affect Pesticide Properties That Affect LeachingLeaching

SolubilitySolubility: ability to dissolve in water; the more : ability to dissolve in water; the more soluble the pesticide, the more likely it will leachsoluble the pesticide, the more likely it will leach

AdsorptionAdsorption: the ability of the pesticide to bind : the ability of the pesticide to bind tightly and quickly to organic matter in the soil tightly and quickly to organic matter in the soil affects leaching; the greater the ability to bind to affects leaching; the greater the ability to bind to organic matter, the less likely pesticides will leachorganic matter, the less likely pesticides will leach

PersistencePersistence: how long the pesticide remains in the : how long the pesticide remains in the soil; pesticides degraded primarily by sunlight, soil soil; pesticides degraded primarily by sunlight, soil microbes and chemicals in the soil; the more microbes and chemicals in the soil; the more persistent a pesticide, the more likely it will leach persistent a pesticide, the more likely it will leach into ground waterinto ground water

Environmental Impact of Environmental Impact of Pesticides in Soil Pesticides in Soil Effects of Effects of

Pesticide Application on LeachingPesticide Application on Leaching Rate of applicationRate of application: the higher the rate : the higher the rate

(amount) of pesticide applied, the greater (amount) of pesticide applied, the greater the chance the pesticides will leachthe chance the pesticides will leach

Application methodApplication method: pesticides applied to : pesticides applied to growing plants can be absorbed by the growing plants can be absorbed by the plants or broken down by sunlight before plants or broken down by sunlight before reaching soil; soil incorporated pesticides are reaching soil; soil incorporated pesticides are not exposed to sunlight and have greatest not exposed to sunlight and have greatest chance of leaching into ground waterchance of leaching into ground water

Environmental Impact of Environmental Impact of Pesticides in SoilPesticides in Soil

Effects of Geography & Weather Effects of Geography & Weather on Leachingon Leaching GeographyGeography: depth from soil surface to ground : depth from soil surface to ground

water (closer ground water is to soil surface, water (closer ground water is to soil surface, the more pesticide leaches into ground water)the more pesticide leaches into ground water)

WeatherWeather: pesticides : pesticides break down faster break down faster in warm, moist soil; in warm, moist soil; therefore, less therefore, less likely likely to leachto leach

Gene Alexander

Environmental Impact of Pesticides in Environmental Impact of Pesticides in Ground WaterGround Water

Ground water is Ground water is water located water located beneath the beneath the earth’s surface, earth’s surface, usually in rock or usually in rock or soilsoil

Ground water is Ground water is the primary the primary source of drinking source of drinking water for 50% of water for 50% of population, 95% of population, 95% of rural residents in rural residents in the United States the United States

Ron Nichols


At least 143 pesticides and 21 of their At least 143 pesticides and 21 of their transformation products have been found in transformation products have been found in ground water, from every major chemical ground water, from every major chemical classclass

Pesticides commonly Pesticides commonly found at low levels found at low levels in agricultural areas in agricultural areas (seldom (seldom exceed water- exceed water- quality standards) quality standards)

Pesticides also found in Pesticides also found in non-agricultural setting non-agricultural setting such as golf courses and such as golf courses and residential areas residential areas

Ken Hammond


Triazine (atrazine) and Triazine (atrazine) and acetanilide (alachlor acetanilide (alachlor and metolachlor) and metolachlor) herbicides: used herbicides: used extensively on corn and extensively on corn and soybeans in Midwestsoybeans in Midwest

Carbamate insecticide Carbamate insecticide aldicarb (Temik): aldicarb (Temik): ground water ground water contamination contamination problems, sampled for problems, sampled for extensivelyextensively

Pesticides most frequently detected in ground water:

Bill Tarpenning


High pesticide usage High pesticide usage in the areain the area

High recharge of High recharge of ground water by ground water by precipitation or precipitation or irrigationirrigation

High soil permeabilityHigh soil permeability Well contamination is Well contamination is

greatest in shallow, greatest in shallow, inadequately sealed inadequately sealed wellswells

Tim McCabe

Factors strongly associated with pesticide contamination ofof ground water are:

Environmental Impact of Pesticides in Environmental Impact of Pesticides in Surface WatersSurface Waters

Surface waters Surface waters include streams, include streams, rivers, lakes, rivers, lakes, reservoirs and reservoirs and oceansoceans

Streams and Streams and reservoirs supply reservoirs supply approximately 50% approximately 50% of the drinking water of the drinking water in United Statesin United States

Ken Hammond


Pesticides enter surface Pesticides enter surface waters through run-off, waters through run-off, wastewater discharges, wastewater discharges, atmospheric deposition atmospheric deposition (dry and precipitation), (dry and precipitation), spills and ground waterspills and ground water

Pesticide Pesticide concentrations in concentrations in surface waters follow surface waters follow the seasonal patterns the seasonal patterns of pesticide application of pesticide application and run-offand run-off

U. S Geological Survey


Low levels of pesticides are widespread in Low levels of pesticides are widespread in surface waters in the United Statessurface waters in the United States

Herbicides are detected Herbicides are detected more frequently than more frequently than insecticides, due to their insecticides, due to their greater use greater use

Some pesticides exceed Some pesticides exceed water-quality standards water-quality standards during certain seasons, during certain seasons, but the annual but the annual average average concentrations seldom concentrations seldom exceed standards exceed standards Doug Wilson


Triazine (atrazine) and Triazine (atrazine) and acetanilide (alachlor and acetanilide (alachlor and metolachlor) and 2,4-D metolachlor) and 2,4-D herbicides: widely used herbicides: widely used in agriculturein agriculture

Carbofuran and diazinon Carbofuran and diazinon were the most frequently were the most frequently detected insecticides in detected insecticides in current usecurrent use

Pesticides most frequently detected in surface waters:

Bill Tarpenning

Environmental Environmental Impact Impact

of Pesticides on of Pesticides on PlantsPlants Pesticides can move Pesticides can move

from the intended from the intended target and damage target and damage nearby plants, nearby plants, including crops, including crops, forests and forests and ornamental plantsornamental plants

PhytotoxicityPhytotoxicity: plant : plant injury resulting from injury resulting from contact with contact with pesticides and/or inert pesticides and/or inert ingredients in ingredients in pesticide formulationspesticide formulations

Scott Bauer

Bruce Fritz

Environmental Impact of Environmental Impact of Pesticides on WildlifePesticides on Wildlife

Fish kills caused by pesticide residues carried into Fish kills caused by pesticide residues carried into waterways by run-off, drift, etc. (e.g., fish kills in waterways by run-off, drift, etc. (e.g., fish kills in Mississippi River resulting from Guthion use in Mississippi River resulting from Guthion use in Louisiana)Louisiana)

Bird kills caused by birds Bird kills caused by birds consuming pesticide-treated consuming pesticide-treated vegetation/insects, pesticide vegetation/insects, pesticide granules, bait or treated seed granules, bait or treated seed (e.g., birds poisoned by (e.g., birds poisoned by eating granular eating granular carbofuran) carbofuran)

Ken Hammond

Acute Poisoning: short exposures to some pesticides may kill or sicken wildlife


Populations of bald eagles and other Populations of bald eagles and other birds of prey were reduced by the birds of prey were reduced by the widespread use of organochlorine widespread use of organochlorine insecticides (DDT) in 1950s and insecticides (DDT) in 1950s and 1960s1960s

These compounds and metabolites These compounds and metabolites caused caused reproductive effects in birdsreproductive effects in birds

Reduction in use of organochlorine Reduction in use of organochlorine insecticides in the insecticides in the 1970s and early 1970s and early 1980s resulted in greatly 1980s resulted in greatly improved improved reproduction and increasing bird reproduction and increasing bird populations populations

Tim McCabe

Chronic Poisoning: exposure to non-lethal levels of pesticides over extended periods can cause reproductive effects, etc.


Predators become sick Predators become sick after feeding on dead after feeding on dead or dying animals or dying animals poisoned by pesticidespoisoned by pesticides

Pesticide residues Pesticide residues move up the food move up the food chain (plants eaten by chain (plants eaten by plant feeding animals plant feeding animals which in turn are which in turn are eaten by predators) eaten by predators)

USDA Photograph

Secondary Poisoning: occurs when animals consume prey that contain pesticide residues and concentrate the pesticide in their bodies (i.e., bioaccumulation) resulting in their poisoning


Herbicides can reduce Herbicides can reduce food, cover and nesting food, cover and nesting sites for wildlifesites for wildlife

Insecticides can reduce Insecticides can reduce insects that serve as insects that serve as food supply for other food supply for other animalsanimals

Plant pollination can be Plant pollination can be effected by reductions effected by reductions in populations of bees in populations of bees and other plant and other plant pollinatorspollinators

Ken Hammond

Indirect Effects: adverse effects caused by the modification or elimination of wildlife habitat or food supply

Endangered and Threatened Endangered and Threatened SpeciesSpecies

of Plants and Animalsof Plants and Animals Endangered speciesEndangered species: “any : “any

species which is in danger of species which is in danger of extinction throughout all or a extinction throughout all or a significant portion of its significant portion of its range”range”

Threatened speciesThreatened species: “any : “any species which is likely to species which is likely to become an endangered become an endangered species within the species within the foreseeable future”foreseeable future”

Endangered / threatened Endangered / threatened species of plants and species of plants and animals protected by the U. animals protected by the U. S. EPA under the federal S. EPA under the federal Endangered Species ActEndangered Species Act

Tim McCabe

Harmful Effects of Pesticides on Harmful Effects of Pesticides on SurfacesSurfaces

Pesticides can leave Pesticides can leave a visible deposit a visible deposit on surfaces (i.e., on surfaces (i.e., clothes, carpets, clothes, carpets, walls, etc.)walls, etc.)

Pesticides can Pesticides can corrode metal corrode metal surfaces (i.e., paint surfaces (i.e., paint on automobiles)on automobiles)

Pesticides can Pesticides can short-circuit short-circuit electrical equipmentelectrical equipment N. C. Pesticide Applicator Training Program

Documents

Environmental Effects of Pesticides Environmental Effects of Pesticides Photograph by Ken Hammond. Stephen J. Toth, Jr. Wayne G. Buhler Department of EntomologyDepartment