Pesticide Safety & Toxicity Dave Moorhead Warnell School of Forest Resources University of Georgia

Pesticide Safety Pesticide Safety & &

ToxicityToxicity

Dave MoorheadDave Moorhead

Warnell School of Forest ResourcesWarnell School of Forest Resources

University of GeorgiaUniversity of Georgia

Pesticides:Pesticides:Chemicals to control unwanted Chemicals to control unwanted

forms of life - Pestsforms of life - Pests

• InsecticidesInsecticidesNurseries Nurseries Seed OrchardsSeed Orchards

PlantationsPlantations

• FungicidesFungicidesNurseriesNurseriesPlantationsPlantations

• HerbicidesHerbicidesNurseries Nurseries PlantationsPlantations

• RepellentsRepellentsWorker useWorker use

Animal use Animal use

Relative ToxicityRelative Toxicity• Organisms can’t differentiate between “natural” and Organisms can’t differentiate between “natural” and

“synthetic” chemicals“synthetic” chemicals

• ““Synthetic” does Synthetic” does notnot mean toxic or poisonous mean toxic or poisonous

• ““Natural” does Natural” does notnot mean safe or even low risk mean safe or even low risk

• Chemicals must be evaluated in their biological context of Chemicals must be evaluated in their biological context of behavior in organismsbehavior in organisms

• Mode of action, not source, is the concernMode of action, not source, is the concern

• Pesticides should be treated with care and proper respect – but Pesticides should be treated with care and proper respect – but so should household cleaners, gasoline and kerosene, bleaches,so should household cleaners, gasoline and kerosene, bleaches, paints and all other chemicalspaints and all other chemicals

Mistretta USFS R-8Mistretta USFS R-8

““I WANT A SPRAY THAT KILLS EVERYTHING BUT ISN’T I WANT A SPRAY THAT KILLS EVERYTHING BUT ISN’T DANGEROUS.”DANGEROUS.”

Relative Toxicity:Relative Toxicity:Are all substances toxic?Are all substances toxic?

YES!YES!

All are toxic to some quantifiable degreeAll are toxic to some quantifiable degree

Sugar has an LDSugar has an LD5050 of 30,000 mg/kg of 30,000 mg/kg

Ethanol has an LDEthanol has an LD5050 of only 13,700 mg/kg of only 13,700 mg/kg

Even water has a recognized LDEven water has a recognized LD5050 of slightly of slightly

greater than 80,000 mg/kggreater than 80,000 mg/kg

Pesticide ToxicityPesticide ToxicityToxicity -Toxicity - measure of ability of a measure of ability of a

chemical to injure /killchemical to injure /kill

Exposure -Exposure - contact with chemicalcontact with chemical

Hazard -Hazard - degree of exposure & toxicity degree of exposure & toxicity levellevel

LDLD50 50 -- lethal dose to kill 50% of test lethal dose to kill 50% of test

animalsanimals

Pesticide ToxicityPesticide ToxicityAcute toxicity -Acute toxicity - injury/death from one injury/death from one

exposureexposure

Chronic toxicity -Chronic toxicity - injury/death after injury/death after

long-term exposurelong-term exposure Oral toxicity -Oral toxicity - injury/death from injury/death from

swallowing chemical swallowing chemical

Dermal toxicityDermal toxicity -- injury/death from injury/death from

exposure to skinexposure to skin

Pesticide ToxicityPesticide Toxicity

PPM (parts per million) -PPM (parts per million) - 1 oz in 1 oz in 62,500 lbs or 1 tbs in 3,906 gal62,500 lbs or 1 tbs in 3,906 gal

PPB (parts per billion) -PPB (parts per billion) - 1000 times less 1000 times less than ppm - 1 tbs in 3,906,000 gal than ppm - 1 tbs in 3,906,000 gal

Half-life -Half-life - time for 1/2 of initial time for 1/2 of initial concentration to be degradedconcentration to be degraded

Volatility -Volatility - ability of a liquid to evaporate ability of a liquid to evaporate

Parts per MillionParts per Million ppmppm

1 liter of water = 1 kg1 liter of water = 1 kg

1 mg / kg = 1 ppm1 mg / kg = 1 ppm

1mm1mm33 / liter = 1 ppm / liter = 1 ppm

1 mg / liter = 1 ppm1 mg / liter = 1 ppm

One part per million isOne part per million is

• 1 inch in 16 miles1 inch in 16 miles

• 1 minute in two years1 minute in two years

• 1 cent in $10,0001 cent in $10,000

• 1 ounce of salt in 31 tons of potato chips1 ounce of salt in 31 tons of potato chips

• 1 bad apple in 2,000 barrels of apples1 bad apple in 2,000 barrels of apples


One part per billion isOne part per billion is

• 1 inch in 16,000 miles 1 inch in 16,000 miles

• 1 second in 32 years1 second in 32 years

• 1 cent in $10,000,0001 cent in $10,000,000

• 1 pinch of salt in 10 tons of potato chips1 pinch of salt in 10 tons of potato chips

• 1 lob in 1,200,000 tennis matches1 lob in 1,200,000 tennis matches

• 1 bad apple in 2,000,000 barrels of apples1 bad apple in 2,000,000 barrels of apples


One part per trillion isOne part per trillion is

• 1 postage stamp in the area of the city of Dallas1 postage stamp in the area of the city of Dallas• 1 inch in 16 million miles (more than 600 times 1 inch in 16 million miles (more than 600 times

around the earth)around the earth)• 1 second in 320 centuries1 second in 320 centuries• 1 flea on 360 million elephants1 flea on 360 million elephants• 1 grain of sugar in an Olympic sized pool1 grain of sugar in an Olympic sized pool• 1 bad apple in 2 billion barrels1 bad apple in 2 billion barrels


Remember –Remember –

• For pesticides – less is more when dealing For pesticides – less is more when dealing with toxicitywith toxicity

• The less you need to cause a toxic effect – The less you need to cause a toxic effect – the more toxic the substance isthe more toxic the substance is

• Thus an LDThus an LD5050 of 25 mg/kg is more toxic of 25 mg/kg is more toxic than is one of 7,000 mg/kgthan is one of 7,000 mg/kg


Signal WordsSignal WordsDANGERDANGER

““Danger” reflects the highest degree of relative Danger” reflects the highest degree of relative toxicity toxicity

All pesticides with an LDAll pesticides with an LD5050 of less than 50 of less than 50

mg/kg must display this word on their labelmg/kg must display this word on their label

Pesticides here are classed as “highly toxic”Pesticides here are classed as “highly toxic”


Signal WordsSignal WordsWARNINGWARNING

““Warning” reflects an intermediate degree of relative Warning” reflects an intermediate degree of relative toxicity toxicity

All pesticides with an LDAll pesticides with an LD5050 of greater than 50 and less of greater than 50 and less than 500 mg/kg must display this word on their labelthan 500 mg/kg must display this word on their label

Pesticides in this category are classed as “moderately Pesticides in this category are classed as “moderately toxic”toxic”


Signal WordsSignal WordsCAUTIONCAUTION

““Caution” reflects the lowest degree of Caution” reflects the lowest degree of relative toxicity relative toxicity

All pesticides with an LDAll pesticides with an LD5050 of greater than of greater than

500 mg/kg must display this word on 500 mg/kg must display this word on their labeltheir label

POISON!!!POISON!!!

• Legally defined term – not just anything you don’t likeLegally defined term – not just anything you don’t like

• Any pesticide with an LDAny pesticide with an LD5050 of 50 mg/kg or less of 50 mg/kg or less

• Labels must reflect this classificationLabels must reflect this classification

• Label must have the signal word “DANGER” plus the Label must have the signal word “DANGER” plus the word “POISON”word “POISON”

• Label also must display the skull and crossbones iconLabel also must display the skull and crossbones icon


Toxicities of Forest PesticidesToxicities of Forest Pesticides

Trade Name Acute oral

LD50

mg/kg Category Signal Word

AAtrex 4L 1075 III Caution

Accord >5000 IV Caution

Arsenal >5000 IV Caution

Garlon 4 1338 III Caution

Tordon 2598 III Caution

Velpar L 6887 IV Caution

Pesticide ToxicityPesticide Toxicity

• Toxicity decreases when mixed (diluted) Toxicity decreases when mixed (diluted) with waterwith water

• 1 gallon of pesticide in 1 gallon of water 1 gallon of pesticide in 1 gallon of water is 50% less toxic is 50% less toxic

• 1 gallon of pesticide in 20 gallons of water 1 gallon of pesticide in 20 gallons of water is 95% less toxicis 95% less toxic

LDLD5050s of field formulationss of field formulations

Garlon 4Garlon 4• Garlon 4 --LD50 = Garlon 4 --LD50 = 1,4191,419 mg/kg mg/kg

• Streamline uses a 17% solution of Streamline uses a 17% solution of Garlon 4 => 1,419 / 0.17 = Garlon 4 => 1,419 / 0.17 = 8,3478,347 mg/kg mg/kg

• Foliar spray is normally done as a 3% Foliar spray is normally done as a 3% solution => 1,419 / 0.03 = solution => 1,419 / 0.03 = 47,30047,300 mg/kg mg/kg


Relative Acute ToxicityRelative Acute Toxicity

• Garlon 4Garlon 4 1,581 mg/kg 1,581 mg/kgRainbow troutRainbow trout 0.74 mg/L 0.74 mg/LBluegillBluegill 0.87 mg/L 0.87 mg/L

• Garlon 3AGarlon 3A 2,574 mg/kg 2,574 mg/kgRainbow troutRainbow trout 117 mg/L 117 mg/LBluegillBluegill 148 mg/L 148 mg/L

• Roundup, Glypro PlusRoundup, Glypro Plus >5,000 mg/kg>5,000 mg/kgRainbow troutRainbow trout 8.2 mg/L 8.2 mg/LBluegillBluegill 5.8 mg/L 5.8 mg/L

• Accord, RodeoAccord, Rodeo >5,000 mg/kg>5,000 mg/kgRainbow troutRainbow trout >1,000 mg/L>1,000 mg/LBluegillBluegill >1,000 mg/L>1,000 mg/L

Tordon RUP?Tordon RUP?

Tordon is a very low-risk herbicide with regard Tordon is a very low-risk herbicide with regard to human health to human health

**High risk of off-site movement****High risk of off-site movement**

Great potential to damage non-target plants Great potential to damage non-target plants over an over an **extended period of time****extended period of time**


PicloramPicloram

PERSISTENCE AND BREAKDOWNPERSISTENCE AND BREAKDOWN

Persistent in soil; half-life may be Persistent in soil; half-life may be 1 year1 year or more, but it is or more, but it is typically 90 days or lesstypically 90 days or less

in the South in favorable conditionsin the South in favorable conditions

Breakdown is by photolysisBreakdown is by photolysis


PicloramPicloram

SOIL ACTIVITY AND MOBILITYSOIL ACTIVITY AND MOBILITY

Soil active; Soil active; highly mobilehighly mobile in soil in soil especially if percolating water is presentespecially if percolating water is present

Tends to be Tends to be excreted by plant rootsexcreted by plant roots; ; results in soil activity even when applied results in soil activity even when applied

by injection or other cut-surface by injection or other cut-surface treatmentstreatments


The Pesticide LabelThe Pesticide Label Information & InstructionsInformation & Instructions

• Precautionary Statements & WarningsPrecautionary Statements & Warnings

• Application, Storage & DisposalApplication, Storage & Disposal

• Chemical FormulationChemical Formulation

The Pesticide LabelThe Pesticide Label Read 4 Times!Read 4 Times!

• Before Buying the PesticideBefore Buying the Pesticide

• Before Preparing the Material for UseBefore Preparing the Material for Use

• Before Mixing &ApplyingBefore Mixing &Applying

• Before Storing or Disposing the PesticideBefore Storing or Disposing the Pesticide

Handling HerbicidesHandling Herbicides

Storage, Transport, & DisposalStorage, Transport, & Disposal StorageStorage

• Approved designated storage areaApproved designated storage areaLockedLockedWarning-Pesticides-Keep OutWarning-Pesticides-Keep OutFire-resistantFire-resistantContainmentContainmentVentilationVentilationInventoryInventory

Storage, Transport, & Disposal Storage, Transport, & Disposal TransportTransport

• Check for damaged containersCheck for damaged containers

• Transport only needed amountsTransport only needed amounts

• Do not transport in passenger sectionDo not transport in passenger section

• Secure containersSecure containers

• Prevent over-heatingPrevent over-heating

Secure herbicide containers when transportingSecure herbicide containers when transporting

Storage, Transport, & Disposal Storage, Transport, & Disposal Spill ProceduresSpill Procedures

• Administer first aidAdminister first aid

• Contain spillContain spill

• Contact manufacturerContact manufacturer

• Dispose of contaminated absorbentDispose of contaminated absorbent

Mixing, Handling , & Applying Mixing, Handling , & Applying PesticidesPesticides

Mixing & HandlingMixing & Handling

• Handling Concentrated FormsHandling Concentrated Forms

• Personal Protection EquipmentPersonal Protection EquipmentGlovesGloves

Eye ProtectionEye ProtectionClothingClothing

• Specific Mixing RecommendationsSpecific Mixing Recommendations

BE CAREFUL WHENBE CAREFUL WHENOPENING HERBICIDEOPENING HERBICIDECONTAINERSCONTAINERSESPECIALLY HOT ONESESPECIALLY HOT ONES

If Accidental Exposure Occurs: If Accidental Exposure Occurs: Immediately Wash Thoroughly With Soap & WaterImmediately Wash Thoroughly With Soap & Water

Carry two emergency eye wash bottlesCarry two emergency eye wash bottles

What to Do if a Herbicide What to Do if a Herbicide Accident OccursAccident Occurs

• Treat injury firstTreat injury first

• Check eyes for contamination & wash out Check eyes for contamination & wash out immediatelyimmediately

• Remove contaminated clothing & wash off Remove contaminated clothing & wash off herbicidesherbicides

• Take a copy of label & Material Safety Data Take a copy of label & Material Safety Data Sheet to DoctorSheet to Doctor

• Notify supervisorNotify supervisor

Mixing, Handling , & Applying Mixing, Handling , & Applying PesticidesPesticides

ApplicationApplication

• PPE, Water & DetergentPPE, Water & Detergent

• Calibration CheckCalibration Check

• Prescribed Cleaning RinsingPrescribed Cleaning Rinsing

• Protect Water Supplies!Protect Water Supplies!

Storage, Transport, & DisposalStorage, Transport, & Disposal DisposalDisposal

• Estimate job requirementsEstimate job requirements

• Mix to avoid excess volumeMix to avoid excess volume

• Triple rinse & dispose/recycle empty Triple rinse & dispose/recycle empty containerscontainers

Protecting the EnvironmentProtecting the EnvironmentConcernsConcerns

• Off-site applicationOff-site application

• Off-site movement in airOff-site movement in air

• Off-site movement in waterOff-site movement in water

• Pesticide persistencePesticide persistence

Off-site Movement GeneralizationsOff-site Movement Generalizations

• More clay and organics = less leachingMore clay and organics = less leaching• Higher temperature = more volatilizationHigher temperature = more volatilization• Lower relative humidity = more volatilizationLower relative humidity = more volatilization• Higher wind speed = more volatilization and Higher wind speed = more volatilization and

driftdrift• Nearer to moving water = higher probability Nearer to moving water = higher probability

of contamination and off-site movementof contamination and off-site movement• Finer droplets = more movementFiner droplets = more movement


Breakdown GeneralizationsBreakdown Generalizations• Hotter temperature = faster breakdownHotter temperature = faster breakdown

• Higher relative humidity = faster breakdownHigher relative humidity = faster breakdown

• More microbes = faster breakdownMore microbes = faster breakdown

• pH effect = chemical dependantpH effect = chemical dependant• • More slope = more runoffMore slope = more runoff


Georgia’s Forestry BMPsGeorgia’s Forestry BMPs BMPs for Chemical ApplicationsBMPs for Chemical Applications

• Establish appropriate SMZ along perennial & Establish appropriate SMZ along perennial & intermittent streams & flowing bodies of waterintermittent streams & flowing bodies of water

• Consider weather conditions (temperature, wind Consider weather conditions (temperature, wind speed & precipitation) equipment capabilities & speed & precipitation) equipment capabilities & pesticide formulations to avoid pesticide drift pesticide formulations to avoid pesticide drift into the SMZinto the SMZ

• Conduct all on-site pesticide handling, such as Conduct all on-site pesticide handling, such as tank mixing, loading & rinsing equipment away tank mixing, loading & rinsing equipment away from streams, ponds, wells, & roadside ditchesfrom streams, ponds, wells, & roadside ditches

Georgia’s Forestry BMPsGeorgia’s Forestry BMPs BMPs for Chemical ApplicationsBMPs for Chemical Applications

• Dispose of pesticide containers &/or excess Dispose of pesticide containers &/or excess pesticides according to local, State & Federal pesticides according to local, State & Federal regulations & label requirementsregulations & label requirements

• Clean up &/or contain all pesticide spills Clean up &/or contain all pesticide spills immediately immediately

• Report spills to GA EPD Emergency Response Report spills to GA EPD Emergency Response Program 1-800-241-4113Program 1-800-241-4113

Georgia’s Forestry BMPsGeorgia’s Forestry BMPs Practices to Avoid During Chemical ApplicationsPractices to Avoid During Chemical Applications

• Applying a pesticide directly to water bodies Applying a pesticide directly to water bodies (streams, lakes, and swamps) unless it is (streams, lakes, and swamps) unless it is specifically prescribed & labeled for aquatic specifically prescribed & labeled for aquatic managementmanagement

• Broadcast applications of pesticides in SMZsBroadcast applications of pesticides in SMZs

On-Line ReferencesOn-Line References

Pesticide Applicator Training Course Pesticide Applicator Training Course USDA Forest Service Region 8USDA Forest Service Region 8

www.bugwood.orgwww.bugwood.org

InformationInformation on the Webon the Web

Bugwood Bugwood

www.bugwood.orgwww.bugwood.org

Forestry ImagesForestry Images

www.forestryimages.orgwww.forestryimages.org

Invasive SpeciesInvasive Species

www.invasive.orgwww.invasive.org

Arsenal InjectionArsenal Injection

MixMix• 20% Arsenal AC20% Arsenal AC

(25 oz +103 oz water)(25 oz +103 oz water)

ApplyApply• 1 injection cut for every 1 injection cut for every

3” stem dbh3” stem dbh

• Spray 1 ml of herbicide Spray 1 ml of herbicide into each cutinto each cut

• Treat August - MarchTreat August - March

Wide –spaced Injection with Wide –spaced Injection with Arsenal for Hardwood ControlArsenal for Hardwood Control

1 quart of Arsenal 1 quart of Arsenal treats 4,700 3” stemstreats 4,700 3” stems

Documents

Pesticide Safety & Toxicity Dave Moorhead Warnell School of Forest Resources University of Georgia