The depletion of dieldrin and DDT concentrations in Kinglake soils

Abstract

Twenty-two sites on 14 former potato growing properties at Kinglake, Victoria, with similar soil type, topography and history of chemical use, were soil tested for organochlorine chemicals during 1987–88 and again during 1997–98. The 95% confidence limits for the decline in concentrations of dieldrin and DDT in the soil were 5.5–41.5% and 29.1–48.5%, respectively. There were no significant differences between farms in the rate of depletion of either organochlorine. Reductions in both to 1997–98 were not significantly associated with the concentration in 1987–88.