BEHAVIOR OF PARATHION RESIDUES IN THE FLORIDA VALENCIA ORANGE AGROECOSYSTEM

Parathion and paraoxon residues were measured in air, on foliage, fruit, and cover crop, and on the soil surfacein a Valencia orange grove ecosystem. On the basis of residues, the greatest potential for worker exposure to parathion was on leaf and soil surfaces. For paraoxon, the greatest potential worker exposure was on the leaf surface. Negligible potential worker exposure was indicated in ambient air or on the fruit surface. Seventy-six percent of the parathion residue behavior on fruit and leaves could be explained by solar radiation, rainfall, and temperature, whereas only 55% of this variation was explained by time alone. Seventy-eight percent of the soil surface parathion residue behavior could be explained by solar radiation, rainfall, and temperature and only 42% with time alone. Solar radiation was the most highly correlated environmental variable with parathion disappearance. Rainfall was the most highly correlated environmental variable with paraoxon disappearance. © 1979, American Chemical Society. All rights reserved.