10 Questions and Answers on Pesticides and Their Use

Man spraying garden with pesticides

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According to the National Safety Council, a pesticide is any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest.

They are used to control a vast array of pests beyond the insect and rodent pests with which most people associate them.

What Products Are Considered to Be Pesticides?

Pesticides used in and around the home may be in the form of sprays, liquids, sticks, powders, crystals, balls, and foggers. They include:

  • Insecticides to control flying and crawling insects, as well as those used on people or pets to prevent bites (such as mosquito spray, flea and tick sprays, and collars, etc.
  • Termiticides to control termites
  • Rodenticides, generally in the form of solid or liquid baits, for control and elimination of rats and mice
  • Fungicides to kill mold and mildew
  • Disinfectants, such as cleaners, sanitizers and even air fresheners to control or eliminate microbes.
  • Herbicides used to kill weeds and other unwanted vegetation.
  • Other products such as pool and spa chemicals, wood treatments and preservatives for decks, etc. can also be defined as pesticides.

Why Are They Hazardous?

Pesticides are produced specifically because they are toxic to specific organisms. Although they are valuable for home and yard maintenance, the inherent toxicity of most pesticides means they can also pose risks to humans at certain levels. Misuse, especially when products are used in inappropriate applications or quantities, can cause illness, injury, and even death.

Shouldn't They Be Safe?

Not necessarily. EPA, which regulates pesticides, does not allow pesticide manufacturers to make safety claims. That is why it is critical the products be used only for the intended purpose and according to all label directions.

How Much Is Dangerous?

It depends. In its overview, EPA quotes the "father of modern toxicology," stating, "The dose makes the poison. In other words, the amount of a substance a person is exposed to is as important as how toxic the chemical might be."

What Are the Possible Health Effects?

Depending on the pesticide and the level and type of exposure or contact, pesticide effects can be as non-threatening as irritation to the eyes, nose, throat, or skin. Or their effects can be much more severe such as damage to the central nervous system and kidney or increased risk of cancer. Symptoms may include a headache, dizziness, muscular weakness, and nausea. Chronic exposure to some pesticides can result in damage to the liver, kidneys, endocrine, and nervous systems. Additionally, exposure to high levels of cyclodiene pesticides (most of which are no longer permitted for use by EPA), commonly associated with misapplication, has produced various symptoms, including headaches, dizziness, muscle twitching, weakness, tingling sensations, and nausea.

Is Exposure Only During Application?

It has been found that measurable levels of up to a dozen pesticides have been found in the air inside homes. While some of this is caused by pesticide use in those households, exposure can also come from contaminated soil or dust that floats or is tracked in from outside, stored pesticide containers, and household surfaces that collect and then release the pesticides.

What Is the Risk of Exposure?

According to EPA, people can be exposed to pesticides in three ways: Inhaling pesticides (inhalation exposure), absorbing pesticides through the skin (dermal exposure), and getting pesticides in their mouth or digestive tract (oral exposure). In 2009, the American Association of Poison Control Centers reported that 92,240 people were exposed to pesticide; 41,882 were ages 5 or younger.

How Can I Reduce Exposure? 

  • It is a good idea to try nonchemical methods of pest control first, then chemical if needed.
  • Before purchasing or using a pesticide, identify the pest, then buy/use only pesticides that have that pest listed on the label.
  • Read and reread the label directions every time you use the pesticide and carefully follow all directions. Use only the labeled amount for the specified time, under the labeled conditions, for the listed purpose and pest(s).
  • Ventilate the area during and after pesticide use.
  • Store pesticides out of the reach of children and pets, preferably in a locked cabinet.
  • Dispose of unused pesticides safely.
  • To check for safety to children, EPA recommends, "Crawl around on your hands and knees to see if you've missed any potential dangers from your child's viewpoint."

What About Hiring a Professional?

NSC advises that "Anyone considering the use of a pest control company should receive satisfactory answers to questions about the company's track record, insurance coverage, licenses, affiliation to professional pest control associations, and the proposed treatment."

Where Can I Get More Information?

Aside from the NSC and EPA, you can go to the National Pesticide Information Center website or call 800-858-PEST.