Pesticide Use: Its Influence on Free Radicals
In recent years, there has been mounting concern over the possible effects of pesticide residues in food. The use of such substances in agriculture is both necessary and widespread. However, many of these materials have been associated with various pathophysiologic phenomena. For example, the herbicide, paraquat, exerts its toxic effects through the intracellular formation of free radicals. Fortunately though, government regulatory mechanisms serve to minimize public exposure. According to the Federal Insecticide, Fungicide, and Rodenticide Act, a pesticide is defined as "any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any insects, rodents, nematodes, fungi, or weeds, or any other forms of life declared to be pests; and any substance or mixture of substances intended for use as a plant regulator, defoliant, or desiccant" (Archibald & Winter, 1990, p. 3). The use of such agents involves both benefits and risks. For example, the pesticides increase crop yields, protect stored food, and enhance the general attractiveness of many food products. It has been estimated that, without them, 40% of the world's food supply might be in jeopardy (Archibald & Winter, 1990, p. 2). However, pesticides may also have negative effects. In general, these compounds are biologically active and can harm the environment. In addition, the presence of undesirable residues in the air, the water, or on food represents a potential threat to human health (Fan & Jackson, 1989, p. 159). Unfortunately though, it is difficult to quantify the negative effects of pesticides. For example, their widespread use does not necessarily mean that residues occur in food. Many pesticides are applied to food crops before the plants emerge from the soil or to trees during the dormant season. This type of application precludes unwarranted exposure of fru...