Lead and cadmium levels in human milk and blood

Lead and cadmium levels were determined (with AAS) in blood and milk obtained at 6 weeks after delivery from women living in the vicinity of a copper and lead metal smelter and in a control area. Analyses of lead and cadmium were also performed in blood samples obtained at delivery. Accuracy of the analysis was confirmed by the analysis of quality control samples. In general, blood and milk levels of lead and cadmium were low in both areas. At 6 weeks after delivery the lead levels in blood and milk were 32 ± 8 and 0.7 ± 0.4 μg Pb/l, respectively (total mean ± S.D., n = 75). Cadmium levels in blood and milk were 0.9 ± 0.3 and 0.06 ± 0.04 μg Cd/l, respectively (n = 75). At delivery the lead levels in blood of women in the smelter area were higher, 38.7 μg Pb/l, than the blood lead levels in women from the control area, 32.3 μg Pb/l, (P < 0.001). At 6 weeks after delivery there was no difference in blood lead levels between the two groups. In contrast, the lead levels in milk were higher in women from the smelter area, 0.9 μg Pb/l, than in women from the control area, 0.5 μg Pb/l, (P < 0.001). No differences in blood cadmium levels were found between the two groups. Milk cadmium levels in women from the control area, 0.07 μg Cd/l, were somewhat higher (P < 0.01) than in women from the smelter area, 0.05 μg Cd/l. Blood cadmium levels were significantly influenced by smoking habits. The mean blood cadmium level for smokers was 1.12 μg Cd/l compared with 0.87 μg Cd/l for non-smokers.