Temporal Trends of Organochlorine Pesticides in Prawn (Macrobrachium nipponense) from Lake Kasumigaura, Japan, During 1978–2000

Abstract

Temporal trends of organochlorine pesticides such as β-hexachlorocyclohexane (β-HCH), hexachlorobenzene (HCB), and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p′-DDE), were determined in freshwater prawn (Macrobrachium nipponense) collected from Lake Kasumigaura in 1978 to 2000. The organochlorine pesticides elucidated a 72.4% decrease in β-HCH, from 42 (1978) to 11.6 ng/g fat (2000); an 89.6% decrease in HCB, from 1.64 (1978) to 0.17 ng/g fat (2000); and an 87.3% decrease in p,p′-DDE, from 97.5 (1978) to 12.4 ng/g fat (1992). After organochlorine pesticide prohibition in 1971, the declining trend of β-HCH, HCB, and p,p′-DDE concentrations persisting in the prawns could be approximated by exponential equations.