Pesticides

Pesticides are substances designed to kill, repel, or mitigate pests. They include a number of chemical and biological agents commonly used in and around the home to control a broad range of pests: insecticides (for insects, including cockroaches, ants, and termites), rodenticides (for mice and rats), fungicides (for mold and fungi), herbicides (for plants), and antimicrobials (for bacteria and viruses).

Use and Exposure

Approximately 4.4 billion pesticide applications are made each year to American homes, gardens, and yards. According to surveys by the Environmental Protection Agency (EPA), more than three-quarters of U.S. households use pesticides, with 66 percent treating major living areas in the home one or more times per year. Cockroaches and ants are the most common targets. More than one-third of households used insecticides in the absence of a major insect problem.

Children may be exposed to pesticides in food, water, and their environments. However, pesticide use in the home, lawn, and garden is responsible for most children’s exposures. Children may come into contact with pesticides that have been applied in the home, or they may gain access to pesticides that have not been stored safely. They also can be exposed to pesticides applied outdoors or to pets. Pesticides used outdoors can contaminate the home when pesticide-laden dust is tracked inside on shoes and pets. The number and concentrations of pesticides found in household dust exceed those found in food, soil, or air. To make matters worse, pesticide contamination in the home can persist for years, particularly in carpets, due to the lack of sun, rain, and other factors that help to break down pesticides outdoors.

Health Impacts

Pesticides can cause a wide range of health problems, ranging from acute and persistent injury to the nervous system, injury to reproductive systems, birth defects, and cancer. Of the 28 pesticides estimated by EPA to be most widely used in agriculture, in and around U.S. homes, and by commercial pesticide applicators, more than 40 percent are classified by EPA as likely, probable, or possible carcinogens, according to a review by the Northwest Coalition for Alternatives to Pesticides (NCAP). Use of these pesticides totals 350 million pounds per year. An EPA database summarizing studies of 19 of these commonly used pesticides indicates that 18 of the 19 have caused reproductive problems in laboratory tests. Immediate health impacts can include dizziness; vomiting; headaches; sweating; skin, eye, and respiratory tract irritation; and fatigue. The health effects from exposure to pesticides vary depending upon the level and duration of exposure. As with most environmental toxins, children are at greater risk from exposure than adults.

Regulation

EPA regulates pesticides used for residential purposes under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). Under FIFRA, EPA can register the use of pesticides or ban or limit their use if they are found to cause unreasonable risks to human health and the environment. The Food Quality Protection Act (FQPA) establishes a higher standard for pesticides used on food: tolerance levels (the maximum amount of pesticide residue permissible on food) must be safe, taking into account exposures from dietary and other sources, as well as the special vulnerability of children to pesticide exposures. While many pesticides are registered for agricultural use, some are registered only for other uses, such as controlling pests in the home.

Subject to some limited exemptions, a pesticide cannot be used legally in the US unless it has been registered with EPA. Since FIFRA was amended in 1988, EPA has been reviewing the health and environmental effects of pesticides registered prior to 1984 to ensure that they meet current, more stringent standards. The 1996 FQPA also requires EPA to review food tolerance levels to ensure their safety and to review pesticide registrations every 15 years.

These review processes have led to bans and use restrictions on some pesticides widely used in the home. For example, chlorpyrifos (marketed by Dow as Dursban) was the most commonly used insecticide in homes, gardens, schools, hospitals, and day care centers for control of cockroaches, ants, fleas, spiders, and ticks. In addition to acute poisonings, chlorpyrifos was found to cause chronic headaches, blurred vision, fatigue, memory loss, depression, irritability, and low birth weights among infants. EPA banned all residential uses in 2004.

In addition to risks presented by older pesticides, some recently registered pesticides may pose health or environmental hazards. According to NCAP, a survey of 19 pesticides registered since 1997 found that nearly all of them posed hazards, including increased risk of cancer, genetic damage, birth defects, and other serious health problems. Some “inert” ingredients cleared for use by EPA also may be harmful.

States also regulate the use of pesticides. States may register pesticides, restrict their use, and establish certification requirements for pesticide applicators. They also may require notification prior to pesticide use and/or posting of areas where pesticides are applied.

Controlling Pests Safely

Pesticides do not offer a long-term, complete solution to pest problems; they kill pests, but typically need to be re-applied periodically. In order to more effectively eliminate pests, it is necessary to identify the factors that are allowing the pests to thrive and alter them. This typically involves eliminating food and water sources and preventing pests from entering the home. This process is known as integrated pest management, or IPM.

Sources and Additional Information:

Asthma, Children, and Pesticides brochure [PDF] – www.beyondpesticides.org/children/asthma/asthma%20brochure%20high%20res.pdf

Beyond Pesticides – www.beyondpesticides.org

Cox, C., Journal of Pesticide Reform, “EPA Takes Action on Diazinon: Too Little, Too Late” (Winter 2000) – www.pesticide.org/diazinonNEWS.pdf

Cox, C., Journal of Pesticide Reform, “Ten Reasons Not to Use Pesticides” (Winter 2001) – www.pesticide.org/TenReasons.pdf

Environmental Health Watch, Pests and Asthma Resources (includes IPM information) – www.ehw.org/Asthma/ASTH_home1.htm#Pests

Gumm, Brian, Home Energy, “Integrated Pest Management in the Home,” Vol. 21 Iss. 6 pp. 36-39 (Nov-Dec 2004)

Natural Resources Defense Council – www.nrdc.org

Northwest Coalition for Alternatives to Pesticides – www.pesticide.org

Northwest Coalition for Alternatives to Pesticides, Journal of Pesticide Reform, “Does Government Registration Mean Pesticides are Safe?” (Summer 1999) – www.pesticide.org/BasicRegistration.pdf

Our Stolen Future – www.ourstolenfuture.org

Pesticide Action Network – www.pesticideinfo.org

Safer Pest Control Project – http://spcpweb.org/

Silent Spring Institute – www.silentspring.org

U.S. Environmental Protection Agency, Pesticides Program – www.epa.gov/pesticides/index.htm

Zahm, S.H., and Ward, M.H., Environmental Health Perspectives, “Pesticides and Childhood Cancer,” Vol. 106 Suppl. 3, pp. 893-908 (June 1998) – http://ehp.niehs.nih.gov/members/1998/Suppl-3/893-908zahm/zahm-full.html