Accumulation of organochlorinated pesticides by triolein-containing semipermeable membrane device (triolein-SPMD) and rainbow trout

摘要

An important advance in aquatic ecotoxicology is the development and application of biomimetic sampling technology for hydrophobic contaminants. In this paper, accumulation kinetics of five organochlorinated pesticides, i.e. hexachlorobenzene, lindan, aldrin, heptachlor epoxide and 4,4′-DDT, by triolein-containing semipermeable membrane device (triolein-SPMD) and by fish (rainbow trout) were compared in a laboratory continuous flow system. Accumulation kinetics of organochlorinated pesticides by the triolein-SPMD and by rainbow trout were linear during the exposure period of 20 d, except for lindan. Approach of an asymptote could be observed for lindan at the end of the exposure for rainbow trout. When the kinetic data were used to calculate the first-order uptake rate constants, it was found that the uptake rates of the chemicals in triolein-SPMD were 1-2.5 times higher than those in the fish. The estimated bioconcentration factors of the five pesticides in rainbow trout were in the range of 1000-7000 and the device concentration factor in the range of 1500-18000. Although equilibrium was not reached for most pesticides under 21-d exposure period, correlations between C_L/C_w and K_(ow) (R~2 = 0.887) and C_f/C_w and K_(ow) (R~2 = 0.931) could be observed which was a clear indication that triolein-SPMD accumulates chlorinated pesticides in a quite similar way as fish do. Our results show that triolein-SPMD could serve as a good surrogate for rainbow trout for simulating accumulations of chlorinated pesticides and may be used as a universal surrogate for fish in natural waters.