A pesticide is any substance or mixture of substances that is intended to repel or destroy a pest1. Pesticides are classified by the type of organism they are designed to control including herbicides for weeds, fungicides for fungus or mold, microbes for bacteria, or insecticides for insects3. Common indoor applications of pesticides control for insects, termites, rodents, fungi, and microbes1. Inherent in their design, pesticides are toxic, so it is important that they be handled properly and that human exposure to them be minimized3. Exposure to pesticides can occur through accidental ingestion, inhalation, or by absorbtion through the skin2.
Pesticides can enter the home by tracking it in from outdoor sources or by using it indoors2. Indoor sources of pesticides come in many forms with a wide variety of products sold as sprays, liquids, solid sticks, powders, crystals, and foggers. The most frequently applied pesticides are those designed for insect control (insecticides) and microbial control (disinfectants)1. Pesticides are made up of both active and inactive ingredients4. The active ingredients directly affect the welfare of the pest, while the inactive ingredients act as carrier agents, permitting the active ingredient to dissolve and access to the pest4. These ingredients are known as semi-volatile chemicals, which means that once released into the environment, they have some desire to be present in the air. The behavior of the pest, its life cycle, and its resistance to the pesticide will each affect where indoor sources of pesticides arise, how long those sources are present, and what the levels are of pesticide chemicals in the indoor air1. As a result, the level of pesticides in homes varies greatly, although current studies suggest a widespread presence of pesticide residues indoors.
With respect to human health, both types of ingredients can contribute to health effects such as eye, nose, and throat irritation, damage to the central nervous system and kidneys, and increased risk of cancer2. Symptoms may include headache, dizziness, muscular weakness, and nausea4. Chronic exposure to some pesticides can result in damage to the liver, kidneys, endocrine and nervous systems4. Although it is known that exposure to the chemicals in pesticides can contribute to adverse health effects, it is not known what concentrations of pesticides are required to induce these effects1. In the absence of more information, erring on the side of caution is well-advised when handling pesticides.
Below is a list of steps created by the United States Environmental Protection Agency (EPA) that help to reduce exposure to pesticides indoors1:
As of yet, there are no air concentration standards for pesticides indoors, but the Environmental Protection Agency recommends ‘Integrated Pest Management', which minimizes the use and hazards of chemical pesticides5. Pesticide products must be used according to application and ventilation instructions provided by the manufacturer.
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