Objective: To estimate the benchmark dose for osteoporosis caused by cadmium exposure in a Chinese general population with an epidemiological study.
Methods: The inhabitants living in both cadmium polluted and non-polluted areas served as the exposure group and the control group. Urinary cadmium (UCd) and Blood cadmium (BCd) were used as exposure biomarkers while the Z score was used as effect biomarker for the osteoporosis.
Results: The UCd and BCd in the habitants of the polluted areas were significantly higher than those in the habitants of the control area on average (P < 0.05) and the UCd and BCd in the habitants of the highly polluted areas were significantly higher than those in the habitants of the moderately polluted area on average (P < 0.05). The bone mineral density was significantly decreased in the groups of the highest UCd and BCd level compared with the 5 microg/g Cr group with the significant difference (P < 0.05). The morbidity of the osteoporosis would increase significantly with the increase of the cadmium exposure (P < 0.05) with the linear correlation (P < 0.05). BMDs were calculated using BMDS Version l.3.2 software and BMDLs were also determined. The BMDL of UCd for cadmium-induced osteoporosis was higher than those representing cadmium-induced renal dysfunction.
Conclusion: High level of cadmium exposure can induce osteoporosis, which occurs later than renal damage related to cadmium exposure. The BMD is a practical method.