The effects of plant-incorporated methylmercury on its distribution, excretion and demethylation patterns in the rat.

Rats were dosed once per os with either plant-incorporated or solution-radioactive methylmercury (MeHg). While whole-body retention did not change, the incorporation into some organs was approx. 2.5 X higher when administered Hg was in the plant-incorporated rather than in solution form. The only noticeable change in demethylation occurred in the cerebrum where MeHg:Hg ratios were 79:10 (plant-incorporated MeHg) and 65:24 (solution-MeHg). Between 5 to 7% of the total mercury was excreted in faeces and urine either in the inorganic (faeces) or organic (urine) forms. Mercury levels in mitochondrial and soluble fractions of cerebrum were noticeably lower with plant-MeHg than with solution-MeHg.