Applying Pesticides Correctly: A Guide for Private and Commercial Applicators

UNIT 6: Harmful Effects and Emergency Response

Learning Objectives

After you complete your study of this unit, you should be able to:

Explain the concepts of hazard, exposure, and toxicity and how they relate to one another,
List the four routes by which your body can be exposed to pesticides, and name the route that should be of most concern to you,
List three factors that determine how quickly pesticides will be absorbed through your skin.
Explain the three main types of harmful effects that pesticides can cause in humans.
Describe how to avoid harmful effects from pesticides.
Describe some general signs and symptoms of pesticide poisoning and of pesticide irritation effects.
Describe appropriate first aid for pesticide exposures.
Define "heat stress" and describe some signs and symptoms of heat stress.
Describe appropriate first aid for heat stress.

Terms to Know

Active Ingredients - The chemicals in a pesticide that control the target pest.
Carrier - The primary material used to allow a pesticide to be dispensed effectively; for example, the talc in a dust formulations, the water mixed with a wettable powder before a spray application, or the air that disperses the pesticide in an air blast application.
Diluent - Anything used to dilute a pesticide.
Dilute - To make less concentrated.
Drift - Pesticide movement away from the release site in the air.
Formulation - Pesticide product as sold, usually a mixture of active and inert ingredients.
Inert ingredients - Inactive components of a pesticide formulation that are used to dilute the pesticide or to make it safer, more effective, easier to measure, mix, and apply, and more convenient to handle.
Labeling - The pesticide product label and other accompanying materials that contain directions that pesticide users are legally required to follow
Personal protective equipment (PPE) - Devices and clothing worn to protect the human body from contact with pesticides or pesticide residues.
Pesticide handling - Directly working with pesticides, such as during mixing, loading, transporting, storing, disposing, and applying, or working on pesticide equipment.
Precautionary statements - Pesticide labeling statements that alert you to possible hazards from use of the pesticide product and that sometimes indicate specific actions to take to avoid the hazards.
Solvent - A liquid, such as water, kerosene, xylene, or alcohol, that will dissolve a pesticide (or other substance) to form a solution.

Harmful Effects and Emergency Response

Most pesticides are designed to harm or kill pests. Because some pests have systems similar to the human system, some pesticides also can harm or kill humans. Fortunately, humans usually can avoid harmful effects by avoiding being exposed to pesticides.

Humans may be harmed by pesticides in two ways: they may be poisoned or injured. Pesticide poisoning is caused by pesticides that harm internal organs or other systems inside the body. Pesticide-related injuries usually arc caused by pesticides that are external irritants.

Pesticides that are chemically similar to one another cause the same type of harmful effects to humans. These effects may be mild or severe, depending on the pesticide involved and the amount of overexposure. But the pattern of illness or injury caused by each chemical group is usually the same. Some chemical families can cause both external irritation injuries and internal poisoning illnesses.

Some pesticides are highly toxic to humans: only a few drops in the mouth or on the skin can cause extremely harmful effects. Other pesticides are less toxic, but too much exposure to them will cause harmful effects also. A good equation to remember is:

Hazard = Toxicity x Exposure

Hazard is the risk of harmful effects from pesticides. Hazard depends on both the toxicity of the pesticide and the exposure you will receive in any situation.

Exposure

When a pesticide comes into contact with a surface or an organism, that contact is called a pesticide exposure. For humans, a pesticide exposure means getting pesticides in or on the body. The toxic effect of a pesticide exposure depends on how much pesticide is involved and how long it remains there.

Types of Exposures

Pesticides contact your body in four main ways:

oral exposure (when you swallow a pesticide),
inhalation exposure (when you inhale a pesticide),
ocular exposure (when you get a pesticide in your eyes), or
dermal exposure (when you get a pesticide on your skin).

Avoiding Exposure

Avoiding and reducing exposures to pesticides will reduce the harmful effects from pesticides. You can avoid exposures by using safety systems, such as closed systems and enclosed cabs, and you can reduce exposures by wearing appropriate personal protective equipment, washing exposed areas often, and keeping your personal protective equipment clean and in good operating condition.

In most pesticide handling situations, the skin is the part of the body that is most likely to receive exposure. Evidence indicates that about 97 percent of all body exposure that happens during pesticide spraying is by contact with the skin. The only time that inhalation is a greater hazard than skin contact is when you are working in a poorly ventilated enclosed space and are using a fumigant or other pesticide that is highly toxic by the inhalation route.

The amount of pesticide that is absorbed through your skin (and eyes) and into your body depends on:

the pesticide itself and the material used to dilute the pesticide. Emulsifiable concentrates, oil-based liquid pesticides, and oil-based diluents (such as xylene) are, in general, absorbed most readily. Water-based pesticides and dilutions (such as wettable and soluble powders and dry flowables) usually are absorbed less readily than the oil-based liquid formulations but more readily than dry formulations. Dusts, granules, and other dry formulations are not absorbed as readily as liquids.
the area of the body exposed. The genital area tends to be the most absorptive. The scalp, car canal, and forehead are also highly absorptive.
the condition of the skin exposed. Cuts, abrasions, and skin rashes allow absorption more readily than intact skin. Hot, sweaty skin will absorb more pesticide than dry, cool skin.

Causes of Exposure

One of the best ways to avoid pesticide exposures is to avoid situations and practices where exposures commonly occur.

Oral exposures often are caused by:

not washing hands before eating, drinking, smoking, or chewing,
mistaking the pesticide for food or drink,
accidentally applying pesticides to food, or
splashing pesticide into the mouth through carelessness or accident.

Inhalation exposures often are caused by:

prolonged contact with pesticides in closed or poorly ventilated spaces,
breathing vapors from fumigants and other toxic pesticides,
breathing vapors, dust, or mist while handling pesticides without appropriate protective equipment,
inhaling vapors present immediately after a pesticide is applied; for example, from drift or from reentering the area too soon, and
using a respirator that fits poorly or using an old or inadequate filter, cartridge, or canister.

Dermal exposures often are caused by:

not washing hands after handling pesticides or their containers,
splashing or spraying pesticides on unprotected skin or eyes,
wearing pesticide-contaminated clothing (including boots and gloves),
applying pesticides (or flagging) in windy weather,
wearing inadequate personal protective equipment while handling pesticides, and
touching pesticide-treated surfaces.

Eye exposures often are caused by:

splashing or spraying pesticides in eyes,
applying pesticides in windy weather without eye protection.
rubbing eyes or forehead with contaminated gloves or hands, and
pouring dust, granule, or powder formulations without eye protection.

Toxicity

Toxicity is a measure of the ability of a pesticide to cause harmful effects. Toxicity depends on:

type and amount of active ingredient(s),
type and amount of carrier or solvent ingredient(s),
type and amount of inert ingredient(s), and
type of formulation, such as dust, granule, powder, or emulsifiable concentrate.

The toxicity of a particular pesticide is measured by subjecting laboratory animals (usually rats, mice, rabbits, and dogs) or tissue cultures to different dosages of the active ingredient and of the formulated product over various time periods. These toxicity studies help to estimate the risk that the pesticide may cause harmful effects in humans. However, some people react more severely or more mildly than estimated. Be alert to your body's reaction to the pesticides you are handling. Some people seem to be especially sensitive to individual pesticides or to groups of similar pesticides.

You may have a choice of pesticides for a particular pest problem. One of the factors you should consider is how toxic each possible choice is to persons who will use it or be exposed to it.

Harmful Effects

Pesticides can cause three types of harmful effects: acute effects, delayed effects, and allergic effects.

Acute Effects

Acute effects are illnesses or injuries that may appear immediately after exposure to a pesticide (usually within 24 hours). Studying a pesticide's relative capability of causing acute effects has been the main way to assess and compare how toxic pesticides are. Acute effects can be measured more accurately than delayed effects, and they are more easily diagnosed than effects that do not appear until long after the exposure. Acute effects usually are obvious and often are reversible if appropriate medical care is given promptly.

Pesticides cause four types of acute effects:

acute oral effects,
acute inhalation effects.
acute dermal effects,
acute eye effects.

Acute oral effects

Your mouth, throat, and stomach can be burned severely by some pesticides. Other pesticides that you swallow will not burn your digestive system, but will be absorbed and carried in your blood throughout your body and may cause you harm in various ways. For some pesticides, swallowing even a few drops from a splash or wiping your mouth with a contaminated glove can make you very ill or make it difficult to eat and drink and get nourishment.

Acute inhalation effects

Your entire respiratory system can be burned by some pesticides, making it difficult to breathe. Other pesticides that you inhale may not harm your respiratory system, but are carried quickly in your blood throughout your whole body where they can harm you in various ways.

Acute dermal and skin irritation effects

Contact with some pesticides will harm your skin. These pesticides may cause your skin to itch, blister, crack, or change color. Other pesticides can pass through your skin and eyes and get into your body. Once inside your body, these pesticides are carried throughout your system where they can cause you harm in various ways.

Acute eye effects

Some pesticides that get into your eyes can cause temporary or permanent blindness or severe irritation. Other pesticides may not irritate your eyes, but pass through your eyes and into your body. These pesticides can travel throughout your body, causing you harm in various ways.

Delayed Effects

Delayed effects are illnesses or injuries that do not appear immediately (within 24 hours) after exposure to a pesticide or combination of pesticides. Often the term "chronic effects" is used to describe delayed effects, but this term is applicable only to certain types of delayed effects.

Delayed effects may be caused by:

repeated exposures to a pesticide, a pesticide group, or a combination of pesticides over a long period of time, or
a single exposure to a pesticide (or combination of pesticides) that causes a harmful reaction that does not become apparent until much later.

Some pesticides cause delayed effects only with repeated exposure over a period of days, months, or even years. For example, if a rat eats a large amount of the pesticide cryolite at one time, the pesticide passes through the rat's system quickly and is eliminated without harmful effects. However, if the rat regularly eats small amounts of cryolite, it soon becomes ill and dies. Cryolite does not readily dissolve in water. The small amount of pesticide that is absorbed into the rat's system from a one-time exposure is not enough
to cause illness. Bur if that same small amount is absorbed day after day, enough poison will be absorbed into the rat's system to cause illness and death.

Sometimes repeated exposures to a pesticide or family of pesticides will result in a delayed effect, but a larger exposure will cause an acute effect. Organophosphate and carbamate pesticides inhibit a chemical, called cholinesterase, in the nervous system of humans. A large exposure causes immediate acute illness. Smaller exposures cause no apparent problem at first. They inhibit the cholinesterase, but not enough to cause immediate illness. Small, repeated exposures to these pesticides over several days or weeks may greatly reduce cholinesterase levels in the body. At that point, even a small exposure to a pesticide with relatively low cholinesterase-inhibiting properties may trigger severe illness.

A person who is repeatedly exposed to two or more specific chemicals may become ill even though anyone of the chemicals alone would have had no harmful health impact. Some organophosphate pesticides have been shown to have this effect when they are used in combination.

In some cases, a single exposure to a pesticide (or combination of pesticides) could adversely affect the exposed person's health after a period of time. For example, large exposures to paraquat, a herbicide, may cause severe or fatal lung injury that does not appear for 3 to 14 days after the initial exposure. After an exposure, paraquat slowly builds up in the lungs and destroys lung cells.

Some kinds of harmful effects may not occur unless a certain set of circumstances is present. These effects can occur after the first exposure, but the likelihood is small. Continuous or frequent exposures over a long period of time make it more likely that all the necessary factors will be present. Some genetic changes that result in the development of cancer or other delayed effects are in this category.

Types of delayed effects include:

chronic effects,
developmental and reproductive effects, and
systemic effects.

Chronic effects

Chronic effects are illnesses or injuries that appear a long time, usually several years after exposure to a pesticide. Some delayed effects that are suspected to result from pesticides' chronic toxicity include:

production of tumors (oncogenic effect).
production of malignancy or cancer (carcinogenic effect),
changes in the genes or chromosomes (mutagenic effect).

Typical precautionary statements on pesticide labeling include:

Cancer Hazard Warning Statement: This product contains an ingredient which has been determined to cause tumors in laboratory animals.

NOTE: This product has been shown to cause cancer in laboratory animals.

The use of this product may he hazardous to your health. This product contains an ingredient which has been determined to cause tumors in laboratory animals.

Developmental and reproductive effects

A developmental effect is an injury or illness that occurs to a fetus in the womb of a woman who has been exposed to a pesticide(s). These effects include:

birth defects (teratogenic effect), and
illness or death (miscarriage or stillbirth) to a fetus (fetotoxic effect).

A reproductive effect is an injury to the reproductive system of exposed men or women. These effects include:

infertility or sterility in men or women, and
impotence in men.

Some developmental or reproductive effects are thought to occur immediately after exposure to a pesticide or combination of pesticides, but they may not be apparent for some time after the exposure. For example, a birth defect may be seen only after the birth of a child, which may be several months after the exposure.

Other developmental or reproductive effects are thought to result from repeated exposures to a pesticide or combination of pesticides over a period of time.

A typical precautionary statement on pesticide labeling is:

This product may be hazardous to your health. This product has been determined to cause birth defects in laboratory animals.

Systemic effects

A delayed systemic effect is an illness or injury to a system in the body that does not appear immediately (within 24 hours) after exposure to a pesticide or combination of pesticides. Such effects include:

blood disorders (hemotoxic effects), such as anemia or an inability to coagulate,
nerve or brain disorders (neurotoxic effects), such as paralysis, nervous excitation, behavioral changes, tremor, blindness, and brain damage,
skin disorders, such as rash, irritation, discoloration, and ulceration,
lung and respiratory disorders, such as emphysema and asthma,
liver and kidney disorders, such as jaundice and kidney failure.

Typical precautionary statements on pesticide labeling include:

May produce kidney and liver damage upon prolonged exposure.

Inhalation may cause delayed lung, nerve, or brain injury.

Liquid or vapor may cause serious skin or eye injury which may have a delayed onset.

Determining delayed effects

Because of the time delay between the exposure and the observable effect, and because many other types of exposures may have occurred during the delay, it is sometimes hard to identify the cause of a delayed effect. Although some pesticides may cause delayed effects in laboratory animals, further studies are needed to determine whether these pesticides will affect humans the same way.

When there is clear evidence that a pesticide may cause chronic, developmental, reproductive, or systemic effects in humans, the Environmental Protection Agency will determine what steps are appropriate to reduce or eliminate the risk. Such actions include:

removing the pesticide from use.
requiring label warning statements about the possible effect,
requiring specific personal protective equipment or safety systems during handling of the pesticide,
requiring changes in dosages, method or frequency of application, and waiting times before entry or harvest/slaughter/grazing.
restricting the use to certified applicators.

Avoiding delayed effects

Scientists, pesticide manufacturers, and the Environmental Protection Agency cannot yet be sure what the delayed effects of too much exposure to individual pesticides or combinations of pesticides may be. It may be years before there are clear answers on the effects of all the pesticides and combinations of pesticides in use today. Meanwhile, it makes good sense to reduce your exposure to all pesticides as much as possible.

Allergic Effects

Allergic effects are harmful effects that some people develop in reaction to substances that do not cause the same reaction in most other people. Allergic reactions are not thought to occur during a person's first exposure to a substance. The first exposure causes the body to develop repelling response chemicals to that substance. A later (the second, third, or more) exposure results in the allergic response. This process is called sensitization, and substances that cause people to become allergic to them are known as sensitizers.

Certain substances cause many people to develop an allergic reaction. Poison ivy, for example, causes a severe skin rash in many people. Other substances cause allergic reactions in only a few people. Turfgrass, for example, causes a severe skin rash in relatively few people.

Types of allergic effects

Some people are sensitized to certain pesticides. After being exposed once or a few times without effect, they develop a severe allergy-like response upon later exposures. These allergic effects include:

systemic effects, such as asthma or even life-threatening shock,
skin irritation, such as rash, blisters, or open sores, and
eye and nose irritation, such as itchy, watery eyes and sneezing.

Unfortunately, there is no way to tell which people may develop allergies to which pesticides. However, certain people seem to be more chemically sensitive than others. They develop an allergic response to many types of chemicals in their environment. These persons may be more likely to develop allergies to pesticides.

Typical precautionary statements on pesticide labeling include:

This product may produce temporary allergic side effects characterized by redness of the eyes, mild bronchial irritation, all redness or rash on exposed skin areas. Persons having allergic reaction should contact a physician.

May be a skin sensitizer.

The active ingredient may cause skin sensitization reactions in certain individuals.

Avoiding allergic effects

Depending on how severe the allergic reaction is, persons with allergies to certain pesticides may have to stop handling or working around those pesticides. They may be unable to tolerate even slight exposures. Sometimes persons with allergies to certain pesticides can continue to work in situations where those pesticides are present by reducing their exposure to them.

Typical Precautionary Statements on Pesticide Labeling

Acute Oral

Highly Toxic: “Fatal if swallowed,” or “Can kill you if swallowed.”
Moderately Toxic: “Harmful or fatal if swallowed,” or “May be fatal if swallowed.”
Slightly Toxic: “Harmful if swallowed,” or “May be harmful if swallowed.”

Acute Inhalation

Highly Toxic: “Poisonous if inhaled,” or “Can kill you if breathed,” combined with the statement “Do not breathe dusts, vapors, or spray mist.”
Moderately Toxic: “Harmful or fatal if inhaled," or "May be fatal if breathed," followed by a statement such as "Do not breathe dusts, vapors, or spray mist."
Slightly Toxic: "Harmful if inhaled," or "May be harmful if breathed," combined with statement "Avoid breathing dusts, vapors or spray mists."

Acute Dermal

Highly Toxic: "Fatal if absorbed through the skin," or "Can kill you by skin contact," combined with the statement "Do not get on skin or clothing."
Moderately Toxic: "Harmful or fatal if absorbed through the skin" or "May be fatal by skin contact," followed by a statement such as "Do not get on skin or clothing."
Slightly Toxic: "Harmful if absorbed through skin," or "May be harmful by skin contact," combined with the statement "Avoid contact with skin or clothing."

Skin Irritation

Highly Toxic: "Corrosive - causes severe skin burns," combined with the statement "Do not get on skin."
Moderately Toxic: "Causes skin irritation," or "Causes skin burns," followed by a statement such as "Do not get on skin."
Slightly Toxic: "May irritate skin," combined with the statement "Avoid contact with skin."

Eye Irritation

Highly Toxic: "Corrosive - causes irreversible eye damage," or "Causes severe eye burns or blindness," combined with the statement "Do not get into eyes."
Moderately Toxic: "Causes eye irritation," or "Causes eye burns," followed by a statement such as "Do not get in eyes."
Slightly Toxic: "May irritate eyes," combined with the statement, "Avoid contact with eyes."

Signs and Symptoms of Harmful Effects

Watch for two kinds of clues to pesticide-related illness or injury. Some clues are feelings that only the person who has been poisoned can notice, such as nausea or headache. These are symptoms. Others clues, like vomiting or fainting, can be noticed by someone else.

These are signs you should know:

what your own symptoms might mean, and
what signs of poisoning to look for in your coworkers and others who may have been exposed.

Many of the signs and symptoms of pesticide poisoning are similar to signs and symptoms of other illnesses you might experience, such as the flu or even a hangover. If you have been working with pesticides and then develop suspicious signs and symptoms, call your physician or poison control center. Only a physician can diagnose pesticide poisoning injuries.

External irritants cause:

redness, blisters, rash, and/or burns on skin, and
swelling, a stinging sensation, and/or burns in eyes, nose, mouth, and throat.

Pesticide poisoning may cause:

nausea, vomiting, diarrhea, and/ or stomach cramps,
headache, dizziness, weakness, and/or confusion,
excessive sweating, chills, and/ or thirst,
chest pains,
difficult breathing,
cramps in your muscles or aches all over your body.

Telltale Signs or Symptoms

Poisoning by some pesticide chemical families results in distinctive signs that help others to recognize the cause of the poisoning. Organophosphate and n-methyl carbamate poisoning, for example, is often identified by the presence of very small (pinpoint) pupils in the victim's eyes. Poisoning by pesticides containing arsenic or phosphorus is often identified by a garlic odor on the victim's breath.

Ask your physician or poison control center to obtain the latest edition of "Recognition and Management or Pesticide Poisonings" by Donald P. Morgan, M.D., Ph.D. It is available through the U.S. Environmental Protection Agency or from the U.S. Government Printing Office. Many physicians have not been trained to recognize and treat pesticide poisonings or injury and may rarely see such cases.

Be Informed

You should know the kinds of harmful effects most likely to be caused by the pesticides you use. The appendix, "Effects of Pesticides on the Human Body," contains a guide to help you judge how the products you are using might be expected to affect you. The chart lists the major groups of pesticides. For each group, it tells:

the action of the poison on the human system,
acute poisoning (systemic) effects,
acute irritation effects,
delayed or allergic effects,
type of pesticide.

Responding to a Poisoning Emergency

Be prepared. When handling pesticides it is necessary to have the label with you, and this label will be very important when seeking medical attention and administering first aid. It is advised that the handlers also have the SDS of each product that they are handling, even adjuvants, as sometimes these products have higher acute toxicity than the pesticide being applied. Get medical advice quickly if you or any of your fellow workers have unusual or unexplained symptoms starting at work or later the same day. Do not let yourself or anyone else get dangerously sick before calling your physician or going to a hospital It is better to be too cautious than too late. Take the pesticide container (or the labeling and SDS if available) to the physician. Do not carry the pesticide container in the passenger space of a car or truck. The information in the label or SDS will provide the physician with valuable information on how to correctly treat the exposed person. For example it may contain information regarding Atropine as a treatment for Organophosphate exposure or have recommendations on weather to induce vomiting or not.

First Aid for Pesticide Poisoning

The best first aid in pesticide emergencies is to stop the source of pesticide exposure as quickly as possible. First aid is the initial effort to help a victim while medical help is on the way. If you are alone with the victim, make sure the victim is breathing and is not being further exposed to the pesticide before you call for emergency help. Apply artificial respiration if the victim is not breathing. Do not become exposed to the pesticide yourself while you are trying to help.

In an emergency, look at the pesticide labeling, if possible. If it gives specific first aid instructions, follow those instructions carefully. If labeling instructions are not available, follow these general guidelines for first aid:

Pesticide on skin:

Drench skin and clothing with plenty of water. Any source of relatively clean water will serve. If possible, immerse the person in a pond, creek, or other body of water. Even water in ditches or irrigation systems will do, unless you think they may have pesticides in them.
Remove personal protective equipment and contaminated clothing.
Wash skin and hair thoroughly with a mild liquid detergent and water. If one is available, a shower is the best way to completely and thoroughly wash and rinse the entire body surface.
Dry victim and wrap in blanket or any clean clothing at hand. Do not allow to become chilled or overheated.
If skin is burned or otherwise injured, cover immediately with loose, clean, dry, soft cloth or bandage.
Do not apply ointments, greases, powders, or other drugs in first aid treatment of burns or injured skin.

Pesticide in eye:

Wash eye quickly but gently.
Use an eyewash dispenser, if available. Otherwise, hold eyelid open and wash with a gentle drip of clean running water positioned so that it flows across the eye rather than directly into the eye.
Rinse eye for 15 minutes or more.
Do not use chemicals or drugs in the rinse water. They may increase the injury.

Inhaled pesticide:

Get victim to fresh air immediately.
If other people are in or near the area, warn them of the danger.
Loosen tight clothing on victim that would constrict breathing.
Apply artificial respiration if breathing has stopped or if the victim's skin is blue. If pesticide or vomit is on the victim's mouth or face, avoid direct contact and use a shaped airway tube, if available, for mouth-to-mouth resuscitation.

Pesticide in mouth or swallowed:

Rinse mouth with plenty of water.
Give victim large amounts (up to 1 quart) of milk or water to drink.
Induce vomiting only if instructions to do so are on the labeling.

Procedure for inducing vomiting:

Position victim face down or kneeling forward. Do not allow victim to lie on his back, because the vomit could enter the lungs and do additional damage.
Put finger or the blunt end of a spoon at the back of victim's throat or give syrup of ipecac.
Do not use salt solutions to induce vomiting.

Do not induce vomiting:

If the victim is unconscious or is having convulsions.
If the victim has swallowed a corrosive poison. A corrosive poison is a strong acid or alkali. It will burn the throat and mouth as severely coming up as it did going down. It may get into the lungs and burn there also.
If the victim has swallowed an emulsifiable concentrate or oil solution. Emulsifiable concentrates and oil solutions may cause death if inhaled during vomiting.

Heat Stress

Heat stress is the illness that occurs when your body is subjected to more heat than it can cope with. Heat stress is not caused by exposure to pesticides, but may affect pesticide handlers who are working in hot conditions. Personal protective equipment worn during pesticide handling activities can increase the risk of heat stress by limiting your body's ability to cool down. If you are under a physician's care, you should consult your physician before working in hot conditions.

Signs and Symptoms of Heat Stress

Mild forms of heat stress will make you feel ill and impair your ability to do a good job. You may get tired sooner, feel weak, be less alert, and be less able to use good judgment. Severe heat stress is a serious illness. Unless victims are cooled down quickly, they can die. Severe heat stress is fatal to more than 10 percent of its victims, even young, healthy adults. Many who survive suffer permanent damage. Sometimes the victims remain highly sensitive to heat for months and are unable to return to the same work.

Learn the signs and symptoms of heat stress and take immediate action to cool down if you suspect you may be suffering from even mild heat stress. Signs and symptoms may include:

fatigue (exhaustion, muscle weakness),
headache, nausea, and chills,
dizziness and fainting,
severe thirst and dry mouth,
clammy skin or hot, dry skin,
heavy sweating or complete lack of sweating,
altered behavior (confusion, slurred speech, quarrelsome or irrational attitude).

First Aid for Heat Stress

It is not always easy to tell the difference between heat stress illness and pesticide poisoning. The signs and symptoms are similar. Don't waste time trying to decide what is causing the illness. Get medical help.

First aid measures for heat stress victims are similar to those for persons who are overexposed to pesticides:

Get the victim into a shaded or cool area.
Cool victim as rapidly as possible by sponging or splashing skin, especially face, neck, hands, and forearms, with cool water or, when possible, immersing in cool water.
Carefully remove all personal protective equipment and any other clothing that may be making the victim too warm,
Have the victim, if conscious, drink as much cool water as possible.
Keep the victim quiet until help arrives.

Severe heat stress or heat stroke is a medical emergency! Brain damage and death may result if treatment is delayed.

Heat Cramps

Heat cramps can be quite painful. These muscle spasms in the legs, arms, or stomach are caused by loss of body salt through heavy sweating. To relieve cramps, have the victim drink lightly salted water or "sports drinks." Stretching or kneading the muscles may temporarily relieve the cramps. However, if you suspect that stomach cramps are being caused by pesticides rather than heavy sweating, get medical help right away.

Know the Law

The Hazard Communication Standard (HCS), a regulation under the Occupational Safety and Health Act (OSHA), requires employers to provide protections to workers who may be exposed to hazardous chemicals undr normal operating conditions or in foreseeable emergencies. The HCS, which is administered by the U.S. Department of Labor, requires employers to:

make a list of the hazardous chemicals in the workplace,
obtain material safety data sheets (MSDS) for all hazardous substances on their list,
ensure that all containers of hazardous materials are labeled at all times,
train all workers about the hazardous materials in their workplace, and
keep a file (including the MSDS's) on the hazardous chemicals, and make it available to workers.

2014 update: When you try to get the MSDS for your pesticide product, you may find a substitute called a “safety data sheet" (SDS) instead.

The Occupational Safety and Health Act (OSHA), administered by the U.S. Department of Labor, contains some requirements that could affect you if you or one of your employees is involved in a pesticide-related injury or illness.

Employers must keep records of all work-related deaths, injuries, and illnesses and make periodic reports. Minor injuries needing only first aid treatment need not be reported. You must keep records if the injury involved medical treatment, loss of consciousness, restriction of work or motion, or transfer to another job.
OSHA will investigate employee complaints related to exposure to hazardous materials, such as pesticides.

TEST YOUR KNOWLEDGE

Q. Explain the terms hazard, toxicity, and exposure and tell how they relate to one another.
A. Hazard is the risk of harmful effects from pesticides. Toxicity is a measure of the ability of a pesticide to cause harmful effects. Exposure is the total amount of pesticide that gets on or in the body. HAZARD = TOXICITY x EXPOSURE.

Q. What are the four routes through which pesticides can contact your body and cause you to be exposed?
A. 1. Oral exposure (when you swallow a pesticide),
2. Inhalation exposure (when you inhale a pesticide),
3. Ocular exposure (when you get a pesticide in your eyes), and
4. Dermal exposure (when you get a pesticide on your skin).

Q. Which route of exposure should you, as a pesticide handler, be most concerned about?
A. Exposure to the skin is the most common route of exposure for pesticide handlers.

Q. What three factors determine how much pesticide will be absorbed through your skin and into your body?
A. The amount of pesticide that is absorbed through your skin (and eyes) and into your body depends on:
1. The pesticide itself and the material used to dilute the pesticide.
2. Which area of the body is exposed.
3. The condition of the skin that is exposed.

Q. Explain acute effects, delayed effects, and allergic effects.
A. Acute effects are illnesses or injuries that may appear immediately after exposure to a pesticide (usually within 24 hours). Delayed effects are illnesses or injuries that do not appear immediately (within 24 hours) after exposure to a pesticide or combination of pesticides. Allergic effects are harmful effects that some people develop in reaction to pesticides that do not cause the same reaction in most other people.

Q. How can you avoid harmful effects from pesticides?
A. Avoiding and reducing exposures to pesticides will reduce the harmful effects from pesticides. You can avoid exposures by using safety systems, such as closed systems and enclosed cabs, and you can reduce exposures by wearing appropriate personal protective equipment, washing exposed areas often, and keeping your personal protective equipment clean and in good operating condition.

Q. Name four signs or symptoms of pesticide poisoning and two signs or symptoms of irritation effects from pesticides.
A. Pesticide poisoning may cause nausea, vomiting, diarrhea, and/or stomach cramps; headache, dizziness, weakness, and/or confusion; excessive sweating, chills, and/or thirst; chest pains; difficult breathing; cramps in your muscles or aches all over your body. External irritants may cause redness, blisters, rash, and/or bums on skin, and swelling, a stinging sensation, and/or bums in eyes, nose, mouth, and throat.

Q. What is the first thing you should do when you or someone else is overexposed to pesticides?
A. The best first aid in pesticide emergencies is to stop the source of pesticide exposure as quickly as possible. If pesticide is on the skin or in the eyes, flood with water; if the pesticide has been swallowed, drink large amounts of water; if the pesticide has been inhaled, get to fresh air.

Q. What is heat stress?
A. Heat stress is the illness that occurs when your body is subjected to more heat than it can cope with.

Q. What are some common signs and symptoms of heat stress?
A. Heat stress may cause fatigue (exhaustion, muscle weakness); headache, nausea, and chills; dizziness and fainting; severe thirst and dry mouth; clammy skin or hot, dry skin; heavy sweating or complete lack of sweating; altered behavior (confusion, slurred speech, and quarrelsome or irrational behavior).

Q. What can Atropine be used to counteract?
A. Organophosphate exposure

Q. If you are not sure whether a person is suffering from heat stress or pesticide poisoning, what should you do?
A. Because so many signs and symptoms could be from either heat stress or pesticide poisoning, do not waste time trying to diagnose the problem - get medical help. In the meantime, get the person to a cooler place that is away from pesticides. Remove personal protective equipment or other clothing that could be contaminating the skin or making the person too warm, use water to clean and cool the skin, and give the person plenty of water to drink.

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