Immunotoxic effects of dialkyltins used for stabilization of plastics

After single administration of di-n-octyltin dichloride (DOTC) 4-61 mg/kg iv, 30-120 mg/kg im, and 120-240 mg/kg p.o.--a reversible, dose-dependent reduction of thymus weight and of the number of thymocytes was observed in mice. Di-n-butyltin dichloride (DBTC) induced similar effects. After iv administration of DBTC the level of total bilirubin in serum of mice was highly increased. DOCT did not elevate the bilirubin content of the serum. The level of bilirubin in serum did not correlate with the thymotoxic effects of DOTC and DBTC in mice. The inhibition of macrophage migration from spleen fragments of guinea pigs, which was measured as a parameter of the cytotoxic activity of DOTC in vitro, appeared at 10(-5)-10(-4) M.