1 / 57

Pesticide Safety & Toxicity

Pesticide Safety & Toxicity. Dave Moorhead Warnell School of Forest Resources University of Georgia. Insecticides Nurseries Seed Orchards Plantations Fungicides Nurseries Plantations. Herbicides Nurseries Plantations Repellents Worker use Animal use .

khylton
Download Presentation

Pesticide Safety & Toxicity

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


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

  2. InsecticidesNurseries Seed Orchards Plantations Fungicides Nurseries Plantations HerbicidesNurseries Plantations Repellents Worker use Animal use Pesticides:Chemicals to control unwanted forms of life - Pests

  3. Relative Toxicity • Organisms can’t differentiate between “natural” and “synthetic” chemicals • “Synthetic” does not mean toxic or poisonous • “Natural” does not mean safe or even low risk • Chemicals must be evaluated in their biological context of behavior in organisms • Mode of action, not source, is the concern • Pesticides should be treated with care and proper respect – but so should household cleaners, gasoline and kerosene, bleaches,paints and all other chemicals Mistretta USFS R-8

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

  5. Relative Toxicity:Are all substances toxic? YES! • All are toxic to some quantifiable degree • Sugar has an LD50 of 30,000 mg/kg • Ethanol has an LD50 of only 13,700 mg/kg • Even water has a recognized LD50 of slightly greater than 80,000 mg/kg

  6. Pesticide Toxicity Toxicity -measure of ability of a chemical to injure /kill Exposure -contact with chemical Hazard - degree of exposure & toxicity level LD50 - lethal dose to kill 50% of test animals

  7. Pesticide Toxicity Acute toxicity -injury/death from one exposure Chronic toxicity -injury/death after long-term exposure Oral toxicity - injury/death from swallowing chemical Dermal toxicity- injury/death from exposure to skin

  8. Pesticide Toxicity PPM (parts per million) -1 oz in 62,500 lbs or 1 tbs in 3,906 gal PPB (parts per billion) -1000 times less than ppm - 1 tbs in 3,906,000 gal Half-life - time for 1/2 of initial concentration to be degraded Volatility - ability of a liquid to evaporate

  9. Parts per Millionppm 1 liter of water = 1 kg 1 mg / kg = 1 ppm 1mm3 / liter = 1 ppm 1 mg / liter = 1 ppm

  10. One part per million is • 1 inch in 16 miles • 1 minute in two years • 1 cent in $10,000 • 1 ounce of salt in 31 tons of potato chips • 1 bad apple in 2,000 barrels of apples Mistretta USFS R-8

  11. One part per billion is • 1 inch in 16,000 miles • 1 second in 32 years • 1 cent in $10,000,000 • 1 pinch of salt in 10 tons of potato chips • 1 lob in 1,200,000 tennis matches • 1 bad apple in 2,000,000 barrels of apples Mistretta USFS R-8

  12. One part per trillion is • 1 postage stamp in the area of the city of Dallas • 1 inch in 16 million miles (more than 600 times around the earth) • 1 second in 320 centuries • 1 flea on 360 million elephants • 1 grain of sugar in an Olympic sized pool • 1 bad apple in 2 billion barrels Mistretta USFS R-8

  13. Remember – • For pesticides – less is more when dealing with toxicity • The less you need to cause a toxic effect – the more toxic the substance is • Thus an LD50 of 25 mg/kg is more toxic than is one of 7,000 mg/kg Mistretta USFS R-8

  14. Signal WordsDANGER “Danger” reflects the highest degree of relative toxicity All pesticides with an LD50 of less than 50 mg/kg must display this word on their label Pesticides here are classed as “highly toxic” Mistretta USFS R-8

  15. Signal WordsWARNING “Warning” reflects an intermediate degree of relative toxicity All pesticides with an LD50 of greater than 50 and less than 500 mg/kg must display this word on their label Pesticides in this category are classed as “moderately toxic” Mistretta USFS R-8

  16. Signal WordsCAUTION “Caution” reflects the lowest degree of relative toxicity All pesticides with an LD50 of greater than 500 mg/kg must display this word on their label

  17. POISON!!! • Legally defined term – not just anything you don’t like • Any pesticide with an LD50 of 50 mg/kg or less • Labels must reflect this classification • Label must have the signal word “DANGER” plus the word “POISON” • Label also must display the skull and crossbones icon Mistretta USFS R-8

  18. Toxicities of Forest Pesticides

  19. Pesticide Toxicity • Toxicity decreases when mixed (diluted) with water • 1 gallon of pesticide in 1 gallon of water is 50% less toxic • 1 gallon of pesticide in 20 gallons of water is 95% less toxic

  20. LD50s of field formulationsGarlon 4 • Garlon 4 --LD50 = 1,419 mg/kg • Streamline uses a 17% solution of Garlon 4 => 1,419 / 0.17 = 8,347 mg/kg • Foliar spray is normally done as a 3% solution => 1,419 / 0.03 = 47,300 mg/kg Mistretta USFS R-8

  21. Relative Acute Toxicity • Garlon 4 1,581 mg/kg Rainbow trout 0.74 mg/L Bluegill 0.87 mg/L • Garlon 3A 2,574 mg/kg Rainbow trout 117 mg/L Bluegill 148 mg/L • Roundup, Glypro Plus >5,000 mg/kg Rainbow trout 8.2 mg/L Bluegill 5.8 mg/L • Accord, Rodeo >5,000 mg/kg Rainbow trout >1,000 mg/L Bluegill >1,000 mg/L

  22. Tordon RUP? Tordon is a very low-risk herbicide with regard to human health **High risk of off-site movement** Great potential to damage non-target plants over an **extended period of time** Mistretta USFS R-8

  23. Picloram PERSISTENCE AND BREAKDOWN Persistent in soil; half-life may be 1 year or more, but it is typically 90 days or less in the South in favorable conditions Breakdown is by photolysis Mistretta USFS R-8

  24. Picloram SOIL ACTIVITY AND MOBILITY Soil active; highly mobile in soil especially if percolating water is present Tends to be excreted by plant roots; results in soil activity even when applied by injection or other cut-surface treatments Mistretta USFS R-8

  25. The Pesticide LabelInformation & Instructions • Precautionary Statements & Warnings • Application, Storage & Disposal • Chemical Formulation

  26. The Pesticide LabelRead 4 Times! • Before Buying the Pesticide • Before Preparing the Material for Use • Before Mixing &Applying • Before Storing or Disposing the Pesticide

  27. Handling Herbicides

  28. Storage, Transport, & DisposalStorage • Approved designated storage area Locked Warning-Pesticides-Keep Out Fire-resistant Containment Ventilation Inventory

  29. Storage, Transport, & Disposal Transport • Check for damaged containers • Transport only needed amounts • Do not transport in passenger section • Secure containers • Prevent over-heating

  30. Secure herbicide containers when transporting

  31. Storage, Transport, & Disposal Spill Procedures • Administer first aid • Contain spill • Contact manufacturer • Dispose of contaminated absorbent

  32. Mixing, Handling , & Applying PesticidesMixing & Handling • Handling Concentrated Forms • Personal Protection Equipment Gloves Eye Protection Clothing • Specific Mixing Recommendations

  33. BE CAREFUL WHEN OPENING HERBICIDE CONTAINERS ESPECIALLY HOT ONES

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

  35. Carry two emergency eye wash bottles

  36. What to Do if a Herbicide Accident Occurs • Treat injury first • Check eyes for contamination & wash out immediately • Remove contaminated clothing & wash off herbicides • Take a copy of label & Material Safety Data Sheet to Doctor • Notify supervisor

  37. Mixing, Handling , & Applying PesticidesApplication • PPE, Water & Detergent • Calibration Check • Prescribed Cleaning Rinsing • Protect Water Supplies!

  38. Storage, Transport, & DisposalDisposal • Estimate job requirements • Mix to avoid excess volume • Triple rinse & dispose/recycle empty containers

  39. Protecting the EnvironmentConcerns • Off-site application • Off-site movement in air • Off-site movement in water • Pesticide persistence

  40. Off-site Movement Generalizations • More clay and organics = less leaching • Higher temperature = more volatilization • Lower relative humidity = more volatilization • Higher wind speed = more volatilization and drift • Nearer to moving water = higher probability of contamination and off-site movement • Finer droplets = more movement Mistretta USFS R-8

  41. Hotter temperature = faster breakdown Higher relative humidity = faster breakdown More microbes = faster breakdown pH effect = chemical dependant More slope = more runoff Breakdown Generalizations Mistretta USFS R-8

  42. Georgia’s Forestry BMPsBMPs for Chemical Applications • Establish appropriate SMZ along perennial & intermittent streams & flowing bodies of water • Consider weather conditions (temperature, wind speed & precipitation) equipment capabilities & pesticide formulations to avoid pesticide drift into the SMZ • Conduct all on-site pesticide handling, such as tank mixing, loading & rinsing equipment away from streams, ponds, wells, & roadside ditches

  43. Georgia’s Forestry BMPsBMPs for Chemical Applications • Dispose of pesticide containers &/or excess pesticides according to local, State & Federal regulations & label requirements • Clean up &/or contain all pesticide spills immediately • Report spills to GA EPD Emergency Response Program 1-800-241-4113

  44. Georgia’s Forestry BMPsPractices to Avoid During Chemical Applications • Applying a pesticide directly to water bodies (streams, lakes, and swamps) unless it is specifically prescribed & labeled for aquatic management • Broadcast applications of pesticides in SMZs

  45. On-Line References Pesticide Applicator Training Course USDA Forest Service Region 8 www.bugwood.org

More Related