[Availability of 14C-carbaryl after oral intake by pregnant rats]

After a single per os administration of an anticholinesterasic drug, 1-naphthyl-N-methyl 14C-carbamate to the pregnant Rat (18th day) we determine 14C activity from blood, liver, kidney, spleen, lung, brain, heart, placenta and foetus at intervals between 1 and 96 hrs. We compare membranous transfer of carbaryl metabolites. Hemato-encephalic diffusion is slow. Intestine and placental transfers are effective from the 1st hr. and of important value.