Occupational exposure occurs through dermal contact and inhalation of sprays, especially to workers applying the compound as an insecticide. Since phosmet has been detected in U.S. foods, exposure to the general population may occur through consumption of foods containing phosmet residues. The US Dept of Agric's Pesticide Properties Database lists a soil half-life of 19 days for phosmet . Insufficient data are available to assess the relative importance of biodegradation in soil. In one screening study, however, hydrolysis rates of the wettable powder formulation of commercial phosmet were slower than found in other hydrolysis studies .
Insufficient data are available to assess the relative importance of biodegradation in water.
Volatilization from water and bioconcentration are not expected to be important fate processes. Particulate-phase phosmet and aerosols released to air during applications of phosmet insecticides will be physcially removed from air by dry and wet deposition. Leachate samples collected near a pesticide manufacturing facility in Barcelona, Spain during the summer of 1984 contained phosmet concns of 5-10 ppm .