Benchmark Dose Estimation for Cadmium-Induced Renal Effects Based on a Large Sample Population from Five Chinese Provinces.

A survey involving 6103 participants from five Chinese provinces was conducted to evaluate the threshold value of urinary cadmium (UCd) for renal dysfunction as benchmark dose low (BMDL). The urinary N-acetyl-β-D-glucosaminidase (UNAG) was chosen as an effect biomarker. The UCd BMDLs for UNAG ranged from 2.18 μg/g creatinine (cr) to 4.26 μg/g cr in the populations of different provinces. The selection of the sample population and area affect the evaluation of the BMDL. The reference level of UCd for renal effects was further evaluated based on the data of all 6103 subjects. With benchmark responses (BMR) of 10%/5%, the overall UCd BMDLs for males in the total population were 3.73/2.08 μg/g cr. The BMD was slightly lower in females, thereby indicating that females may be relatively more sensitive to Cd exposure than are males.