Potential Harmful Effects of Pesticides

David Fourqurean

The two broad types of effects from pesticide exposure are: local or contact and systemic.
Local effects may occur to the area of contact with skin, eyes, or respiratory tract. They are referred to as contact symptoms or effects. Examples of local (contact) effects:

  • Skin irritation or injury; itching, redness, rashes, blisters, burns, and discoloration. Many herbicides and fungicides cause dermatitis. Fumigants can cause severe blisters.
  • Eye irritation or injury: swelling, stinging, and burning. Herbicides, fungicides, insecticides, and fumigants may cause eye irritation or injury through contact, sometimes resulting in irreversible damage.
  • Nose, mouth, or throat irritation or injury: Swelling, stinging, and burning. Permanent respiratory damage occurs less often.

Systemic effects may occur once the substance is absorbed and distributed throughout the body. They may be acute or chronic. These effects depend on the toxicological profile of the chemical itself, the amount absorbed, and the individual’s ability to detoxify and eliminate the chemical. Examples of systemic effects are:

  • Damage to nerves.
  • Reduced ability of blood to clot.
  • Some cancers.
  • Reproductive problems.
  • Impaired metabolism (the body’s ability to use energy).
  • Hormonal effects.
  • Damage to various organ systems, such as the kidneys or liver.

The U.S. Environmental Protection Agency (EPA) considers local and systemic effects when deciding whether to register a chemical. They are also used to set label restrictions, such as limiting the method, timing, or rate of application; to determine appropriate levels of PPE; or to establish restricted entry intervals (REIs) in combination with exposure factors.

Allergic effects are harmful effects that occur in some people after exposure to certain substances. An allergy to a chemical contained in a product formulation may cause skin irritation, blisters, or hives. Occasionally, more serious problems, such as asthma or even life-threatening shock can develop.

Pesticide allergy symptoms include red and/or itchy eyes, respiratory discomfort, and asthma-like effects. Unfortunately, there is no way to predict which people will develop allergies to a particular product. Having an allergic reaction does not predict whether someone would also be more sensitive to other effects of the pesticide, such as chronic or delayed effects. These types of effects depend on different chemical reactions within the body.

Always, always read and follow label information to avoid any pesticide related exposure problems that can occur when applying pesticides. Attend a proper training course to be able to recognize any health related problems that might occur during or after pesticide application and be able to render proper first aid to the affected person.