The Association of Cadmium Exposure and Anthropometrics in School-Age Children: A Longitudinal Study

Objective There is currently conflicting evidence about the potential effects of cadmium (Cd), a common heavy metal pollutant, on children's physical development. Therefore, we explored the association between school-age children's exposure to cadmium and a number of anthropometric measurements. Methods Data from a development cohort of 699 children in an urban district of Chongqing, southwest of China were used. At baseline, we collected urine from children and used Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) to evaluate the amounts of cadmium in the urine. Anthropometric measurements were conducted at baseline and two follow-ups, with body mass index (BMI), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) calculated. A linear mixed model (LMM) was employed to assess the impact of urine cadmium concentration on these anthropometric indices. Results Our findings indicated that urinary cadmium concentration was negatively associated with WC (β[95%CI]=-1.83[-3.43, -0.23]), HC (β[95%CI]=-1.56[-2.95, -0.17]), and WHtR (β[95%CI]=-0.01[-0.02, -0.00]). Analysis of follow-up data indicated that for each additional time unit (six months), the higher the cadmium levels in children's urine, the slower their height growth rate, while their WHtR growth rates are faster. Conclusion Cadmium exposure in school-aged children is associated with slower height growth and is negatively correlated with WC, HC, and WHtR. Limiting cadmium exposure in children as early as possible is therefore essential.