[Excretion of urinary metallothionein and osteal damage induced by cadmium in an environmentally cadmium exposed population].

OBJECTIVE

To observe the relationship between urinary metallothionein excretion and osteal damage induced by cadmium in a general population.

METHODS

The inhabitants living in both cadmium polluted and non-polluted areas were asked to participate in this study. Urinary cadmium (UCd) and blood cadmium (BCd) were measured by GF-AAS. Total cadmium(TCd)was evaluated with environmental cadmium exposure. URBP, UB2M, UALB and UMT were measured by ELISA method. UNAG, UNAGB were measured by fluorescence analysis method. Forearm bone mineral density in human were mensurated by SPA.

RESULTS

UMT can reflect the change of cadmium body burden. Renal dysfunction and osteoporosis would appear successively after high level of cadmium exposure. UMT had a complex relationship with bone mineral density which related to the amount of UMT excretion. The BMDLs of UCd were calculated using software of BMDS Versionl. 3.2 for these biomarkers. The values of BMDL of these biomarkers were arranged: UNAGB < UNAG < UB2M < UMT < URBP < Tscore < UALB.

CONCLUSION

Cadmium exposure could induce bone damage which occurred later than renal dysfunction related to cadmium exposure. UMT could be not only a specific and sensitive biological indicator of cadmium-induced renal dysfunction but also could reflect the damage on bone induced by cadmium.