safe herbicide use environmental consequences social concerns max williamson
TRANSCRIPT
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
LD50
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/kgNormally 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
• Carbaryl 270.0 mg.kg
• Malathion 370.0 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 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
Primary Routes of Exposureto 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:CAUTIONWARNINGDANGER
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