Migration and Accumulation of Octachlorodipropyl Ether in Soil-Tea Systems in Young and Old Tea Gardens

The migration and accumulation of octachlorodipropyl ether (OCDPE) in soil-tea systems were investigated using a gas chromatography-electron capture detector (GC-ECD) method in young and old tea gardens. When the residual concentration of OCDPE was 100 g a.i. hm(−2) in soils, the peak concentrations of OCDPE in fresh leaves of young and old tea plants were 0.365 mg/kg and 0.144 mg/kg, taking 45 days and 55 days, respectively. Equations for the accumulation curves of OCDPE in fresh leaves of young and old tea plants were C(t) = 0.0227e(0.0566t) (R(2) = 0.9154) and C(t) = 0.0298e(−0.0306t) (R(2) = 0.7156), and were C(t) = 3.8435e(0.055t) (R(2) = 0.9698) and C(t) = 1.5627e(−0.048t) (R(2) = 0.9634) for dissipation curves, with a half-life of 14.4 days and 12.6 days, respectively. These results have practical guiding significance for controlling tea food safety.