Levels of Urine Cadmium in Children from Non-Polluted Areas of China

Objectives: The database on cadmium (Cd) concentration in children is limited, especially in China. The present study aimed at evaluating the body burden of Cd and to propose reference values for urine Cd in young children, who lived in areas with no point sources of metal exposure.
Methods: Overall, 1170 children aged from 1 month to 17 years old were enrolled in the study. A questionnaire was used to obtain essential information about age, gender, etc. Urine samples were collected to determine urinary Cd and urine creatinine.
Results: A total of 1070 children, 544 males and 526 females, were included in the analysis. Based upon their age, the population was divided to three age groups (0 to 5 years, 6 to 11 years, and 12 to 17 years). The reference value of urinary Cd for children without disease and Cd exposure was as follows: 0 to 5 years < 0.56 g/L, 6 to 11 years < 0.65 g/L, and 12 to 17 years < 0.74 g/L. The reference value of urinary Cd adjusted by urine specific gravity was as follows: 0 to 5 years < 0.83 g/L, 6 to 11 years < 0.01 g/L, and 12 to 17 years < 1.15g/L. The reference value of urinary Cd corrected by urinary creatinine was as follows: 0 to 5 years < 2.17g/L, 6 to 11 years < 1.23 g/L, and 12 to 17 years < 1.25 g/L.
Conclusions: In this study, we determined urine cadmium levels in children from non-polluted areas in china. The reference intervals could be used to offer recommendations for clinical work.