Pesticides are defined by the US Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) as "any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest, and any substance or mixture of substances intended for use as a plant regulator, defoliant, or desiccant."24,109 Pesticides are most commonly categorized into four major and several minor classes based on the intended targets. The four major classes are insecticides, herbicides (weeds), fungicides (fungi and molds), and rodenticides. Minor classes include acaricides and miticides (mites), molluscides (snails etc.), larvicides, pediculocides (lice), nematocides, and scabicides, as well as attractants (pheromones), defoliants, dessicants, plant regulators, and repellants.23 Currently, the Annual Report of the American Association of Poison Control Centers, National Poison Data System (AAPCC-NPDS) lists six categories of pesticides: fumigants, fungicides, herbicides, insecticides, repellents, and rodenticides. In 2007, the total number of exposures mentioned was 95,657, of which 85,617 were described as unintentional and 43,469 were in children younger than 6 years of age. Remarkably, despite these large numbers, fewer than 20 annual deaths were attributed to all pesticides by AAPCC in 2006 and 2007 (Chap. 135).
Since 1947, the production, use, and distribution of pesticides in the United States have been regulated under FIFRA and its subsequent amendments in 1972, 1975, and 1978. In 1970, the Environmental Protection Agency (EPA) was given the authority to administer and enforce FIFRA regulations. Under FIFRA, all pesticides and their manufacturers must be registered with the EPA, and the pesticide must be classified for either general use or restricted use by licensed or certified applicators. Also, a pesticide must be sold exactly as formulated, registered, and labeled. Failure to comply with any of these regulations can result in civil and criminal penalties, and product recall, seizure, or ban from future sales.109 The EPA and FDA together establish pesticide tolerance concentrations for agricultural products and foods, and the 1978 amendment to FIFRA allows individual states to enact and enforce pesticide regulations, resulting in some states establishing even more stringent requirements and lower acceptable concentrations than EPA itself.109 However, the EPA retains the authority to act when states are unable or unwilling to do so.
In addition to its authority under FIFRA, the EPA regulates pesticides under several other acts: the Federal Environmental Pesticide Control Act; the Resource Conservation Recovery Act of 1972 (RCRA); the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, also called the "superfund" Act); the Toxic Substance Control Act (TSCA); the Clean Water Act and the Safe Drinking Water Act.
FIFRA is granted considerable authority to protect the health of the population. When evidence indicates that a pesticide may pose a significant hazard, one or more of the following actions may be taken: permissible workplace exposure limits may be issued, a product may be removed from sale or its registration canceled, restrictions on use or application of a product may be ordered and tolerance concentrations ...