Toxicokinetic and metabolic study of dimethylnitrosamine and diethylnitrosamine in crayfish Austropotamobius pallipes

Abstract

1. The acute toxicities of dimethylnitrosamine and diethylnitrosamine have been evaluated in adult male crayfish Austropotamobius pallipes; LD₅₀ values are 2250 mg/kg and 230 mg/kg, respectively.

2. Toxicokinetic studies of ¹⁴C-dimethylnitrosamine and ¹⁴C-diethylnitrosamine in crayfish, administered by i.v. injection, show high concentrations of ¹⁴C in abdominal muscle and hepatopancreas. Excretion is greater with dimethylnitrosamine, and retention in the tissues, especially the hepatopancreas, is greater with diethylnitrosamine.

3. Metabolites identified in excreta include monomethylnitrosamine from dimethylnitrosamine, and hydroxyethyl-ethyl-, bishydroxyethyl- and carboxyethyl-ethyl-nitrosamine from diethylnitrosamine.