Pesticide loss to the atmosphere

Pesticides may be transformed by chemical and biological processes or transported from the site of application by several processes including runoff, movement through the soil to ground water, volatilization, transport on soil particles, and wind erosion. Contamination of water by pesticide residues is a matter of concern as is contamination of the earth's atmosphere. The form in which a pesticide enters the air and the dimensions of pesticide-containing particulate matter affect movement and deposition. Local transport over distances of several miles may be responsible for adverse effects on nontarget species. Effects of long-range transport are more difficult to assess, but pesticides increase the burden of organic chemicals in the atmosphere. Field measurements of pesticide volatilization and deposition of residues in rainfall, particulate matter, fog, etc., provide information on the relative importance of these processes. Adequate information concerning chemical reactions of pesticides in air is lacking. Because it is desirable to minimize low-level human and environmental exposure resulting from airborne pesticide residues, potential for losses to the air should be taken into account in selecting pesticide formulations and application methods.