The statute authorizes EPA to exempt a pesticide from the requirements that would ordinarily apply if the agency determines that the substance is either adequately regulated by another federal agency or of a character that is unnecessary to regulate under FIFRA to carry out the purposes of that statute (US Congress 1947, section 136 w(b)). Examples of exemptions issued by EPA are shampoo products designed to kill head lice and subject to FDA regulation as human drugs; articles treated with pesticides, such as insect-protected lumber and mildew-resistant paints, in which the pesticides are already registered for such use; and natural and synthetic pheromones when used in traps (EPA 1988a, sections 152.20b, 152.25a, and 152.25b). EPA has also issued regulations identifying substances that are not considered pesticides at all because they are not for use against pests or not used for a pesticidal effect (EPA 1988a, sections 152.8 and 152.10). Such substances include fertilizers, plant nutrients, deodorizers, and products that exclude pests by providing a physical barrier and that contain no toxicants, such as pruning paints for trees. In sharp contrast with pesticides exempted from FIFRA regulation, substances that EPA deems to fall outside the definition of a pesticide are subject to regulation under other federal statutes, such as section 409 of FFDCA (US Congress 1958) for food additives, the Toxic Substances Control Act (US Congress 1976b) for industrial and consumer chemicals, and the Consumer Product Safety Act (US Congress 1976a).
Modern genetic techniques permit the development of plants that produce their own pesticides or are otherwise resistant to insects, viruses, and other plant pests. That capability is in some respects an extension of conventional plant breeding techniques that attempt to select the heartiest and most disease-resistant strains for use in producing hybrid seeds and plants for commercial agriculture and home gardens. Plants and other macroorganisms with pesticidal properties have been exempted from the requirements of FIFRA for many years (EPA 1988a, section 152.20a). The exemption was established before any consideration of modern biotechnology to exempt the many plant species that are naturally pest-protected (such as chrysanthemums) and insects and other macroorganisms (such as lady bugs and praying mantises) that act as natural pest control agents (OSTP 1986, p. 23320). EPA refers to this entire category of products as “biological control agents. ”
To be registered under FIFRA, a pesticide must not cause “unreasonable adverse effects on the environment”. This phrase is defined as including both ecological concerns and risks to human health. Traditionally, that criterion required EPA to balance the potential adverse effects associated with the use of compounds that are often inherently toxic against their social, economic, and environmental benefits (US Congress