Association Between Lead Exposure and Anthropometric Indicators in School-aged Children: A Longitudinal Study

Objective To investigate the association between lead exposure and anthropometric indicators in school-aged children. Methods Data were derived from a cohort of children in a district of Chongqing, Southwest China. At baseline, a self-administered questionnaire was used to collect information on date of birth, sex, parental education, household income per capita, residence, birth weight, and feeding practices during the first six months. Anthropometric measurements were conducted at baseline and during three follow-up visits. Urinary lead levels were quantified using inductively coupled plasma mass spectrometry (ICP-MS). Linear mixed-effects models were employed to evaluate the impact of urinary lead concentrations on anthropometric outcomes. Results A total of 699 children (423 boys and 276 girls) with a mean age of 7.92 ± 0.88 years were included. Urinary lead levels were negatively associated with body weight (β = -1.83; 95% CI: -3.14, -0.51), BMI (β = -0.70; 95% CI: -1.26, -0.14), WC (β = -2.16; 95% CI: -3.81, -0.51), HC (β = -1.69; 95% CI: -3.08, -0.30), WtHR(β = -0.01; 95% CI: -0.02, 0.00), and BF% (β= -1.75; 95% CI: -3.43, -0.08). Longitudinal analysis indicated that, over each six-month interval, higher urinary lead levels were associated with an accelerated increase in BF% within a certain range. Conclusion Lead exposure in school-aged children is negatively associated with body weight, BMI, WC, HC, and BF%.These findings underscore the importance of minimizing lead exposure in children as early as possible.