Severe lead contamination among children of samurai families in Edo period Japan

This paper presents evidence for severe lead contamination among children of samurai families living in a castle town in Edo period Japan (1603–1867). Excavated rib bones were analyzed by atomic absorption, and soft X-ray roentgenograms of long bones were taken. The median values of lead concentration in the bones of children 3 years of age and under(1241.0 μg Pb/g dry bone) and 4–6 years of age (462.5 μg Pb/g dry bone) were significantly higher than those of adult males (14.3 μg Pb/g dry bone) and females (23.6 μg Pb/g dry bone) (p < 0.001). In addition, that of children over 6 years of age (313.0 μg Pb/g dry bone) was significantly higher than those of adult males (p < 0.01) and adult females (p < 0.05). The median value of lead in the bones of children 3 years of age and under was over fifty times higher than that of their mothers (adult females). Hypertrophy was seen in the long bones of five samurai children. In this area, lead lines or lead bands were distinguished by soft X-ray roentgenogram. Samurai children suffered from severe lead contamination in Edo period Japan. When the mothers were nursing their children, the children might have ingested their mother’s white lead non-selectively.