Distribution
The human body has been estimated to contain less than 17 mg of tin, with approximately 6 mg in soft tissues and the remaining fraction associated with skeletal tissues (ICRP 1981a). In a survey of tin concentrations in postmortem human tissues collected from several hundred subjects, the highest concentrations occurred in the kidney, liver, lung, and bone (Kehoe et al. 1940; Schroeder et al. 1964; see Table 3-13). Tin was not detected in brain tissue (Kehoe et al. 1940). In kidney and liver, the highest concentrations (kidney 57–60 mg/kg, liver 48–61 mg/kg) were observed at ages 1–10 years; concentrations were 20–40 mg/kg thereafter; tin was not detected in kidney or liver at birth (Schroeder et al. 1964). In the lungs, tin appeared to increase with age, with the highest levels (53–64 mg tin/kg) at ages 51–84 (Schroeder et al. 1964). Although, these data indicate trends in tin accumulation in human tissues, wide variations in tissue concentrations were observed, most likely