Effects of N,N-dimethylformamide and its degradation products in zebrafish embryos.

The response of zebrafish (Brachydanio rerio) embryos, cultured in reconstituted water, to continuous treatment with N,N-dimethylformamide (DMF) or its degradation products until hatching, was investigated. The embryos were distinctly susceptible to DMF, N-(hydroxymethyl)-N-methylformamide (DMF-OH), N-methylformamide (NMF), N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC), and formamide (FA). Concentrations of 18 (DMF-OH), 121 (DMF), 163 (AMCC), 186 (NMF) and 203 (FA) mmol/litre produced 50% embryo lethality (LC(50)). Only treatment with DMF, NMF or FA induced malformations, involving curvature of the spine and tail and reduction of heart size and action with decreased blood circulation.