Objective To observe the changes of mineral elements' levels in biological samples of chronic cadmium poisoning patients and to provide references for the treatment of chronic cadmium poisoning.

Methods Chronic cadmium poisoning workers (n=200) in a nickel-cadmium battery factory were chosen as the observation group, and another 200 healthy workers in the same factory were chosen as the control group. Cadmium, calcium, magnesium, zinc, iron, copper, and selenium levels in blood and urine samples of the two groups were examined for statistical analysis.

Results Compared with the healthy workers, the urinary concentrations of calcium, zinc, iron, copper, and selenium in the cadmium poisoning patients were higher (P < 0.01); however, the blood concentrations of calcium, zinc, iron, and copper were lower (P < 0.01). Among the observation workers grouped by urinary cadmium concentrations, the concentrations of zinc, copper, and selenium showed significant difference (P < 0.05), while the concentrations of calcium, magnesium, and iron showed no significant difference (P > 0.05). Among the observation workers grouped by blood cadmium concentrations, the concentrations of iron and copper showed significant difference (P < 0.05), while the concentrations of calcium, magnesium, zinc, and selenium showed no significant difference (P > 0.05).

Conclusion Chronic cadmium poisoning could cause metabolic disturbance of mineral elements in human body, especially calcium, zinc, iron, and copper.