Lead in teeth of weanling rats received via the maternal drinking water.

Pregnant rats were dosed with 0, 3 or 10 parts/10(6) lead (as acetate) in their drinking water, during pregnancy and during lactation until 21 days post partum. The litters were killed at the age of 21 days and the incisors, first, second and third molars analysed for lead by atomic absorption spectrophotometry. The findings confirmed that even at low concentrations lead has an affinity for hard tissues. The mean lead levels of the teeth of the three groups differed at the 1 per cent level. Pb levels of the first and second molars and the incisors also differed at the 1 per cent level. No significant differences between the four types of teeth within a group could be demonstrated. The no-effect level of Pb administered in drinking water, to the mother during lactation, and during pregnancy, was lower than 3 parts/10(6).