Pesticide Safety – Part I – Video (timer)

The student is to:

(1) Watch the Video.

(2) Read the print version of the lesson below.

(3) The link to the test will magically appear at the bottom of the lesson once the 50 minute timer has expired.  When this occurs, click on the link to the test and answer the questions provided.

General: Pesticide Safety – Part I

Introduction

• Virtually 100% of the U.S. population has some pesticide residue in their body.
• Approximately 30 people die of pesticide poisoning in the U.S. each year.
• Estimated $3.00 return per $1.00 invested in pest control measures.

Benefits of Pesticide Use

• Control of disease organisms, weeds and insects.
• Lower food prices.
• Protection of structures from damage caused by termites and other wood destroying insects.
• Prevention of disease outbreaks due to rodent and insect populations.
• Sanitation of drinking and recreational water.
• Disinfections of indoor areas as well and dental and surgical instruments.
• Taxes paid by pesticide manufacturers, distributors, dealers, commercial applicators and farmers.

Risks of Pesticide Use

• Acute poisoning caused by short-term exposure to a pesticide.
• Chronic effects caused by long-term exposure to pesticides.
• Degradation of natural resources when pesticides enter surface waters or ground water.
• Injury to nontarget plants, birds, fish, or other wildlife.
• Soil and water contamination when pesticides are mishandled.

Pesticide Toxicity

• Definition – The inherent capability of a substance to produce injury or death.
• In contrast, Hazard is the probability that injury will result from the use of a pesticide in a given formulation, quantity or manner.
• Any chemical substance is toxic/poisonous if absorbed by the body in excessive amounts.
• Different pesticides can vary greatly in their level of toxicity.
• Pesticide toxicity is generally expressed as LD₅₀ or LC₅₀ value.  These represent the lethal dose or lethal concentration required to kill 50% of a test population.
• The toxicity of a pesticide can vary greatly based on the species of animal, test method, sex of the animal, the animal’s health, purity of the chemical tested, carrier in which the pesticide is administered, route of administration, time length and frequency of exposure.
• LD₅₀ values are simply a statistic. They provide no information on the dosage that will be fatal to a specific member of a population.
• The LD₅₀ value is usually expressed in terms of a single dosage such as:

Acute oral – single dosage taken or ingested by mouth.

Acute dermal – single dosage applied to and absorbed by the skin.

• LD₅₀ values provide little or no information as to the possible cumulative effects of a pesticide.

Pesticide Toxicity Categories

Toxicity Category I:

• Labeled “Danger-Poison” if based on its oral, inhalation or dermal toxicity and the word “Poison” will be in red with a skull and crossbones in the immediate proximity of the word poison.
• Labeled “Danger” alone where the pesticide is corrosive, causes severe eye and skin burning but is not highly toxic orally or through inhalation.

Toxicity: Highly toxic

Signal word: Danger-Poison or Danger

Oral LD₅₀: 0-50mg/kg

Dermal LD₅₀: 0-200 mg/kg

Inhalation LC₅₀: 0-2000 µg/l

Toxicity Category II:

Toxicity: Moderately toxic

Signal word: Warning

Oral LD₅₀: 50-500 mg/kg

Dermal LD₅₀: 200-2000 mg/kg

Inhalation LC₅₀: 2000-20,000 µg/l

Toxicity Category III:

Toxicity: Slightly toxic

Signal word: Caution

Oral LD₅₀ : 500-5000 mg/kg

Dermal LD₅₀: 2,000-20,000 mg/kg

Inhalation LC₅₀: Over 20,000 µg/l

Toxicity Category IV:

Toxicity: Relatively nontoxic

Signal word: Caution

Oral LD₅₀: ˃ 5000 mg/kg

Dermal LD₅₀: ˃ 20,000 mg/kg

Chronic Toxicity

This relates to the effects of prolonged or repeated exposures to low levels of a poisonous substance and is dose related.  Chronic effects may include tumors, cancer, reproductive problems such as sterility and birth defects, damage to the nervous system, damage or degeneration of internal organs such as the liver and allergic sensitization to certain chemicals.

Pesticide Entry into the Body

Pesticides can enter the body through the skin, mouth, eyes and lungs.

     Dermal

• People are most frequently exposed to chemicals by contact with the skin.
• Pesticides that are oil soluble penetrate the skin more readily than water soluble compounds.
• To prevent dermal exposure, wear protective clothing and avoid plants that have been recently treated.

Oral

• Contaminated food or beverages
• Splashing pesticide solution or dust into mouth while mixing or spraying.
• Smoking
• Keeping mouth closed
• Protective equipment over the mouth
• Wash thoroughly before eating, drinking or smoking.
• Keep beverages and food away from areas where pesticides are stored mixed or applied.
• Keep pesticides in their original packages.
• Never store a pesticide in a container that can be mistaken for a food or beverage container.

Respiratory

• Once in the lungs, pesticides are quickly adsorbed and transported throughout the body.
• A respirator should be worn when mixing and applying pesticides.
• The pesticide label should be read to see if there are special instructions regarding respiratory equipment.

Eyes

• Chemical contact with the eyes may result in serious injury.
• Pesticides can be absorbed into bloodstream through the eyes.
• Face shield or goggles

Symptoms of Pesticide Exposure

• Acute symptoms appear shortly after a person is exposed to a pesticide.
• Chronic symptoms appear weeks, months or even years after being exposed to a pesticide.
• Chronic symptoms may appear suddenly or gradually.
• Common symptoms of pesticides exposure include skin rashes, headaches, or irritation of the eyes, nose or throat.
• Other symptoms of exposure include blurred vision, dizziness, heavy sweating, weakness, nausea, stomach pain, vomiting, diarrhea, extreme thirst and blistered skin.
• May also result in apprehension, restlessness, anxiety, unusual behavior, shaking, convulsions or unconsciousness.
• Symptoms of an allergic reaction to a pesticide can include breathing difficulties, sneezing, eye watering and itching, skin rashes, apprehension, and general discomfort.

Applicator Safety 

      Selecting a Pesticide

• Ability to control the target pest versus effects on nontarget organisms.
• Economic or aesthetic injury level, health problem or nuisance
• Emulsifiable concentrates that contain a petroleum based carrier are generally more hazardous to the user than water soluble pesticides since they readily penetrate the skin and are more difficult to wash off.
• Granular-type formulations are generally safer than sprays and dusts because they drift less.

      Loading and Mixing Pesticides

• This is the most hazardous time when using a pesticide.
• Always read the pesticide label before mixing or loading a pesticide.
• Never work alone.
• Mix outside or in well ventilated area.
• Measure in clean containers of appropriate size.
• Triple rinse containers before disposed.
• Immediately clean up spills.
• Pesticide spilled on the skin should be immediately washed off with soap and water.
• Wash off protective gloves before removing.
• Never smoke, eat or drink while handling a pesticide.
• Never use one’s mouth to siphon a pesticide from a container.
• To prevent back siphoning, never allow the hose or pipe used to fill a spray tank to be below the highest possible water surface.

      Pesticide Application

• Read the label before applying a pesticide.
• Use protective clothing prescribed in the label.
• Never apply at a higher rate or dosage than that prescribed in the label.
• Properly calibrate and maintain application equipment.
• When there is a breeze, the applicator should drive at right angles to the wind to prevent the pesticide from blowing onto the applicator.

Training

• The employer is responsible for providing the applicator with the proper equipment and training.

Continuing Education

• It is the responsibility of all who work with pesticides to keep current with the pesticide laws and regulations.
• Pest control applicators must continue their education in order to stay in touch with modern pest control practices and pesticide application techniques.

      Medical Exams

      An individual who applies pesticides should have periodic medical checkups.

Planning for Accidents

• Always be prepared for an accident.
• Always have an emergency source of water for washing an exposed person’s eyes and skin.
• Be familiar with the first aid required to treat a person exposed to a pesticide.
• Have the necessary emergency numbers on-hand in case of an emergency. Many cities have a “911” emergency number that can be called.

Medications and Alcohol

• Alcohol should not be consumed before, during or immediately after a pesticide application.
• If taking any kind of medication, consult a physician before handling a pesticide.

Material Safety Data Sheets

      Material Safety Data Sheets (MSDSs) are available for every pesticide label.  These can be obtained from the         manufacturer or pesticide supplier.

Pesticide Label

        A pesticide label is a legal document that one is obligated to follow.  By law, an individual is not allowed to use a pesticide in a manner not consistent with label instructions.

The pesticide label should be thoroughly read and understood each time a person handles a chemical.

References

Bohmont, B. L. 2007. The standard pesticide users guide. 7th ed. Pearson Prentice-Hall,     Upper Saddle River, N. J., Columbus, Ohio.

Marer, P. J. 2000. The safe and effective use of pesticides. University of California Publ.    3324.

Renchie, D. L. 2009. Texas pesticide applicator general. Texas AgriLife Extension Service Publ. B-5073.

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