PPesticides cause four types of acute effects: Oral, Inhalation, Skin, and Eye – 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 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.
Acute inhalation effects — Your entire respiratory system can be burned by some pesticides, making it difficult to breathe. Other pesticides that you may inhale may not harmyour respiratory system but are carried quickly in your blood throughout your whole body where they can harm you.
Acute dermal 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 harm you.
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, harming you.
Delayed effects are illnesses or injuries that donot 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.
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. A person who is repeatedly exposed to two or more specific chemicals may become ill even though any one of the chemicals alone would have had no harmful health impact.
In some cases, a single exposure to a pesticide (or combination of pesticides) could adversely affect the exposed person’s health later. For example, large exposures to herbicide paraquat 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), or ▪ changes in the genes or chromosomes (mutagenic effect).
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 EPA 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 effects, 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 EPA 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 used today. Meanwhile, it makes good sense to reduce your exposure to all pesticides as much as possible.
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. Later exposures result 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 lifethreatening 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, and redness or rash on exposed skin areas. Persons having allergic reactions should contact a physician.”
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.
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 under 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) forall hazardous substances on their list and keep them in a file that is available to all workers,
- ensure that all containers of hazardous materials are labeled at all times,
- train all workers about the hazardous materials in their workplace.