Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments

摘要

The partitioning, bioavailability, and toxicity of cypermethrin in water-sediment systems was investigated. Cypermethrin adsorbed extensively and rapidly, with an overall mean organic carbon(OC) adsorption partition coefficient(K_oc) of 350,000, and approximately 99/100 adsorption occurred within 24 h. Bioavailability was measured via body burdens of Daphnia magna and Chironomus tentans. Mean biota-sediment accumulation factor (BSAFs), that is, the concentration in the organism as a proportion Of the concentration in the sediment, decreased with increasing OC content. The BSAF values were 0.31, 0.14, and 0.08 for D. Magna and 0.63, 0.19, and 0.08 for C. tentans, in 1, 3, and 13/100 OC sediments, respectively.