Mercury concentration in organs of contemporary Japanese

Concentrations of inorganic mercury (IHg), methylmercury (MeHg), and total mercury (THg) were determined for autopsy samples from 46 Japanese subjects. Two laboratories (Labs A and B) participated in Hg analyses: Lab A for THg and IHg and Lab B for THg and MeHg. Total mercury concentration values were in good agreement between the two laboratories: the averages were several hundreds of ng/g in kidney cortex, kidney medulla, and liver, and were several tens of ng/g in cerebrum, cerebellum, heart, and spleen. Inorganic mercury accumulated more in kidney and liver: its percentage THg was 81-84% in the kidney, 67% in the liver, 25% in the heart, 22% in the spleen, 20% in the cerebrum, and 14% in the cerebellum. Methylmercury levels in tissues were uniform through all organs except the liver. Approximately 80% was in the form of MeHg in the cerebrum, cerebellum, heart, and spleen, whereas the values were 33%, 15%, and 11% in the liver, kidney medulla, and kidney cortex, respectively. Age was a significant factor in increased IHg concentrations in the cerebrum and heart, decreased values of %MeHg in the cerebrum, cerebellum, and heart, and increased values of %IHg in the cerebrum and heart.