Colorado Pesticide Exam Turf: Environmental Concerns, Laws and Regulations, Applicator Safety

Transportation (examples)

movement of a pesticide away from its intended site of action

examples: leaching, runoff, volatilization, particle drift, adsorption, plant absorption

Transformation (examples)

when a pesticides chemical structure is altered, usually a desirable fate, because most pesticides used today become less toxic or nontoxic

examples: photodecomposition, microbial decomposition, chemical degradation

Leaching

downward movement of pesticides and nutrients through the soil, carries pesticide and nutrient contaminants to groundwater resources

Soil organic matter and leaching

has a greater ability to stop the movement of pesticides

Runoff

occurs when the precipitation rate exceeds the rate of water infiltration into the soil

Volatilization

when a pesticide changes from a solid or liquid phase to gaseous phase, this increases with temperature

Vapor pressure

point where solids vaporize and liquids evaporate

Esters

a compound formed by the union of an organic acid and an organic base, they have a greater tendency to volatize than amine forms

How to reduce particle drift

- use the lowest practical pressure

- leave an untreated edge

- angle nozzle toward ground, slightly forward in direction of travel

- use nozzles with largest practical openings

- use low-volatile formulations of chemicals

- spray when wind speed is low

- do not spray during a temperature inversion

- spray when sensitive vegetation is not actively growing

Temperature inversion

warm air traps cooler air near the earth's surface

Adsorption

pesticides binding or sticking to a surface (pesticides that adsorb to soil are less likely to leach)

Absorption

movement of pesticides into a plant, most pesticides are then broken down by the plant

Photodecomposition

sunlight-induced transformation, generally alter chemical properties of a pesticide making it less toxic or effective

Microbial decomposition

most common means of pesticide degradation where microorganisms use the pesticide as a food source resulting in degradation, may alter the structure of the pesticide usually resulting in detoxification

What conditions encourage microbial activity in soil?

warm, moist soil that is well aerated and has a pH range of 6.5-7

Hydrolysis

the way a pesticide reacts with water, may be enhanced or reduced by the presence of mineral or organic absorbing surfaces

Two ways a nontarget organism may be harmed by pesticides

- cause injury by contacting directly

- leave a residue that causes later injuries

Residue

part of a pesticide remaining in the environment after an application or spill

Rate of pesticide breakdown may be affected by environmental conditions such as

- surface type, chemical composition, and pH

- surface moisture

- presence of microorganisms

- temperature

- exposure to direct sunlight

Persistence

how long a pesticide remains in an active form in the environment, persistent pesticides do not break down

Accumulative pesticides

these build up in plants, animals or the environment

Considerations for contamination of ground and surface water

- proximity of treated area to surface waters, wells, and aquifers

- depth of the water table

- soil conditions

- hazard of pesticide (potential to contaminate)

- conditions during application that affect drift into surface waters

- IPM practices that minimize leaching

Written statement for pesticide application includes

- statement that pesticide has been applied

- pesticide type applied

- date of application

- precautionary statements

Sign notifying public of application requirements

bottom of sign at least 18" aboveground, top of the sign no higher than 48" above ground

Single residences sign requirements

must be posted 2-5 feet from the road or property boundary, if not easy to see due to landscape, place each flag so it can be seen to anyone entering the property

Sign requirements for greenbelts, parks, golf courses, athletic fields, playgrounds, common property of multi-residential and commercial properties, or similar recreational or common property

post signs immediately next to areas within property where pesticides have been applied so they can easily be seen and read by anyone entering the treated area(s)

post a sign at any and all logical entrances onto the treated area for anyone entering or leaving the property

Notice-of-application sign requirements

- must be water resistant

- measure at least 4" high x 5" wide

- black lettering on bright yellow background

- the word "WARNING" in at least 60 point bold

- the words "PESTICIDES APPLIED" in at least 24 point bold

- symbol of a circle at least two inches in diameter with diagonal slash over an adult, child, and dog

- name of applicator in 18 point bold

Notice-of-application sign requirements when owner is not present

in at least 18 point bold:

- telephone number of applicator

- name of pesticide applied

- date the pesticide was applied

Endangered Species Act

it is unlawful to "take" any animal listed as an endangered species by the USFWS ("take"= harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or attempt to do any of these)

Endangered Species Act penalties

$25k for each violation, criminal penalties up to $50k or imprisonment for 1 year

Citizen suit provision

private citizens may sue the Secretary of the Interior to compel enforcement actions against a violator or to enjoin any activity threatening an endangered species

Toxicity

the potential a substance has to produce injury or death to humans, animals, or plants

Hazard

also known as risk, is the possibility that injury will result from the use of a substance in a given formulation, quantity, or manner

hazard/risk = toxicity + exposure

Pesticide can be extremely toxic but presents little hazard to applicator when used

- in a very dilute formulation

- in a formulation that is not readily absorbed through the skin or inhaled

- humans are not being exposed

- properly equipped to handle chemical safely

A chemical low in toxicity but present a hazard

- normally used in a concentrated form

- rapidly absorbed or inhaled

- used frequently by untrained persons who become exposed to it

LD50

lethal dose: dose that will kill 50% of a large population of test animals

LC50

lethal concentration: concentration in air or water that will kill 50% of test animals

Toxicity values for acute oral or dermal

mg per kg of body weight, micrograms of mist or dust per liter of air, parts per million (ppm) by volume of gas or vapor

Chronic poisoning

result of prolonged exposure to small amounts of a pesticide that create long-term effects

Acute poisoning

a single, substantial exposure to a dose of toxicant that creates immediate effects

Most common route of exposure

dermal contact

When is the danger of dermal exposure at its greatest?

when the temperature is high and the skin is wet or skin abrasions and cuts are present

Guidelines to reduce likelihood of oral ingestion

- store pesticides in original labeled containers

- never use your mouth to clear a spray hose or nozzle or to begin siphoning a pesticide

- never eat, drink, or use tobacco until after leaving the work area and washing thoroughly

Of inhalation poisoning, what poses the greatest risk of exposure?

vapors and very small particles

The most significant health hazard pesticides (families) and why

Organophosphates and Carbamates, they inhibit cholinesterase

Acephate and chlorpyrifos

examples of organophosphates

Carbaryl

example of a carbamate

Cholinesterase

enzyme essential to proper functioning of the nervous system

Signs and symptoms of MILD exposure to organophosphates and carbamates

- headache, fatigue, dizziness, loss of appetite, nausea, stomach cramps, diarrhea

- blurred vision associated with excessive tearing

- contracted pupils

- excessive sweating and salivation

- slowed heartbeat (less than 50 per min)

- rippling of surface muscles

Signs and symptoms of MODERATELY SEVERE organophosphates and carbamates poisoning

- unable to walk

- chest discomfort and tightness

- constriction of pupils

- muscle twitching

- involuntary urination and bowel movement

Signs and symptoms of SEVERE organophosphates and carbamates poisoning

- Incontinence (no control of bowel movement)

- Unconsciousness

- Seizures

Pyrethroids

synthetically produced compounds of naturally occurring biological insecticides extracted from chrysanthemum flower heads

not very toxic, kidney can excrete

Permethrin and deltamethrin

examples of pyrethroids

Triazines

herbicides that are often formulated as emulsifiable concentrates and liquids, not very toxic

usually moderately irritating to eyes, skin, and respiratory tract

Atrazine and metribuzin

examples of triazines

Chlorophenoxy

also referred to as phenoxy acid herbicides, sometimes mixed into commercial fertilizers to control growth of broadleaf weeds

2,4-D and mecoprop (MCPP)

examples of chlorophenoxy

Chlorophenoxy signs/symptoms

ingestion causes vomiting, diarrhea, headache, confusion, and bizarre or aggressive behavior, a particular odor is on breath

Substituted Benzenes

fungicides that are often formulated as wettable powders or granules

Chlorothalonil and pentachlorbenzene

examples of substituted benzenes

Chlorothalonil

available as wettable powders, water dispersible granules, and flowable powders

can cause irritation of skin, mucous membranes of the eye, and respiratory tract on contact

Pentachlorobenzene (PCNB)

used to treat soil, formulations include emulsifiable concentrates, wettable powders, and granules

high concentrations and prolonged contact cause sensitization in some

Ethylene Bis Dithiocarbamates (EBDC compounds) signs/symptoms

fungicides which may cause irritation of skin, respiratory tract and eyes, sometimes systemic toxicity

Mancozeb

example of EBDC and formulated as dust, wettable powders, and liquid flowable powders

Arsenical Pesticides

many compounds have been discontinued in the US due to government regulations

Monosodium methane arsonate (MSMA)

example of arsenic compound used in turf

Signs/symptoms of acute arsenic poisoning

usually appear within one hour after ingestion but may be delayed several hours

garlic odor of the breath and feces may help to identify the toxicant in a severely poisoned person

metallic taste in the mouth

vomiting, abdominal pain, and watery or bloody diarrhea

How the central nervous system (CNS) is affected by acute arsenic exposure

headache, dizziness, drowsiness, and confusion

progress into muscle weakness/spasms, hypothermia, lethargy, delirium, coma, and convulsions

death usually occurs 1-3 days following symptoms and is the result of circulatory failure, renal (kidney) failure may contribute

Hypersensitivity can occur when

repeated minor exposure occurs with many kinds of pesticide products, may create adverse reactions to a family of chemicals

Where to find information for chemical spills

CHEMTREC: provides information on hazardous materials to local emergency responders and links them with the shipper, product manufacturer, or other expert resources

To the manufacturer, the label is:

a license to sell

To the state or federal government, the label is:

a way to control the distribution, storage, sale, use, and disposal of the product

To the dealer and user, the label indicates:

if the pesticide is general or restricted use

To the buyer or the user, the label is:

a main source of facts on how to use the product correctly and legally, it is a way to tell users about special safety measures needed

To dealers and pest control experts, the label is:

an aid in making recommendations to buyers and users

To physicians, the label is:

a way to determine what antidote or first aid procedure to use in the treatment of poisoning cases