Cadmium-exposed population in Mae Sot District, Tak Province: 4 bone mineral density in persons with high cadmium exposure.

OBJECTIVE

To measure bone mineral density in cadmium-exposed persons aged 40 years and older that lived in the 12 contaminated villages in northwestern Thailand.

MATERIAL AND METHOD

Five hundred seventy three persons with urinary cadmium levels > or = 5 microg/g creatinine during the 2004-2006 surveys were screened in 2007 for urinary excretion of cadmium, bone formation and resorption markers, and renalfunction markers. Calcaneus bone density was measured in each person by a dual-energy X-ray absorptiometry bone scanner.

RESULTS

The mean age of the study persons was 57 years old. The geometric mean level of urinary cadmium for women was significantly higher than that for men. Women had a lower mean of calcaneus bone density than men. The rate of osteoporosis in women (21.5%) was significantly higher than that for men (14.7%). Calcaneus bone density was negatively correlated with urinary excretion of calcium (in both genders) and crosslinked N-telopeptide of type I collagen (in women), after adjusting for other co-variables. Increasing urinary cadmium levels appeared to correlate with reduced bone density in women, but not in men. In both genders, urinary excretion of beta2-microglobulin and N-acetyl-beta-D-glucosaminidase was higher in persons with osteoporosis than those without.

CONCLUSION

Bone mineral loss is correlated with urinary cadmium levels and renal dysfunction in this female population.