Safe Herbicide Use Environmental Consequences Social Concerns Max Williamson

Pesticide Any substance or mixture of substances used to kill, destroy,repel, prevent or mitigate a pest.

Pesticide Names Chemical name Common name Product name There are three names associated with every pesticide.

Toxicity- Extent or degree to which a chemical substance is poisonous to humans/animals

Measures of Toxicity: The Median Lethal Dose LD 50 The amount (dose) of a chemical which produces death in 50% of a population of test animals to which it is administered by any of a variety of methods mg/kg Normally expressed as milligrams of substance per kilogram of animal body weight

 Acute Toxicity-Effects of a Single Dose  Chronic Toxicity-Effects after a Long Term Exposure

SUBCHRONIC/CHRONIC TESTING ( Long-term, low level exposures). Carcinogenicity (cancer). Reproduction/fertility. Teratogenicity (birth defects). Delayed neurotoxicity (nervous system). Dominant lethal (potential for genetic change)

Relative Acute Toxicity: Insecticides Parathion 13.0 mg/kg Paraquat 95.0 mg/kg Carbaryl270.0 mg.kg Malathion370.0 mg/kg

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

Relative Toxicity: Are all substances toxic? YES!  All are toxic to some quantifiable degree  Sugar has an LD 50 of 30,000 mg/kg  Ethanol has an LD 50 of only 13,700 mg/kg  Even water has a recognized LD 50 of slightly greater than 80,000 mg/kg

Primary Routes of Exposure to Pesticides There are three primary routes by which organisms are exposed to pesticides Oral Inhalation Dermal

Signal Words The relative acute toxicity of a pesticide is reflected on the label in the form of a “signal word” The (toxicologically) appropriate signal word MUST appear on every pesticide label The three possible signal words are: CAUTION WARNING DANGER

Formulator Product name EPA Registr # Statement of Ingredients Signal words & human health precautions WPS Precautions General information

Worker Protection Standard EPA’s requirements for workers and handlers of pesticides

Social Concerns Communications

Environmental Movement r

Does your Herbicide have a Range and Pasture Label?

Carefully kept records allow you to honestly answer questions without relying on, sometimes selective, memory

Good communication requires that sufficient accurate information be given

Appropriate Tools of Communication Accurate information and Appropriate language

Always try to know your audience

Don’t prejudice yourself based on labels There are almost always surprises Environmental scientist Wildlife biologist Senator-Physician

WHERE AND WHO Often the most effective places for communication are the places where you normally meet people - the country store, the grocery, your church,... this means that technicians and temporaries are often doing the talking – keep them up to speed on projects

Don’t promise things that you can’t deliver! “I WANT A SPRAY THAT KILLS EVERYTHING BUT ISN’T DANGEROUS.”

DON’T !!!

What To Do: Be prepared; know your material Listen carefully Keep your cool Keep the level of discussion appropriate to the audience and, everything else we have said in this talk But, most of all, USE COMMON SENSE!

Maintain records of what you are doing and what is going on in your pesticide program

Seek Experienced Assistance