THE ROLE OF SOIL AND ACTIVE INGREDIENT PROPERTIES IN DEGRADATION OF PESTICIDES - A PRELIMINARY ASSESSMENT

Pesticide disappearance from soils was observed in laboratory studies in which leaching and runoff were impeded, and volatilisation and degr adation evaluated. Advection by volatilisation was negligible for the less volatile chemicals, and significant for the more volatile (Triflu ralin and Heptachlor). Basic statistics applied to degradation DT50 da ta of 14 active ingredients in four different soils showed that the pr operties of pesticides play a major role in determining their degradab ility.