Effect of Calcium Supplementation on School Children's Blood Lead Levels in Indonesia

Population exposures to lead are mainly related to vehicle exhaust, in areas where leaded-gasoline is still being used, paint and lead solder in canned food, drinking water pipes, and from certain culturally-based exposures, such as use of lead-glazed ceramics or traditional medication. It is well documented that excess exposure to lead causes health problems in children including neurobehavioral deficits. The objective of this study was to examine the effect of daily calcium supplementation for a three months period on reducing blood lead levels (BLLs) among elementary school children aged 9 to 11 years old in Bandung, Indonesia. Forty elementary schools were randomly selected, 400 children enrolled, and a total of 298 children completed follow-up of 3 months periode. Schools were divided randomly into two groups of calcium-supplement intervention groups (250 mg and 500 mg) and one control group with no intervention. Capillary blood samples were analyzed for lead levels before and after three months of calcium supplementation. Paired-t test, ANOVA, and multivariate risk factors models using Generalized Estimating Equations (GEE) were performed. The percent reduction in BLLs for each group was 15.1 % (no calcium) from the baseline of 13.7 ug/dL, 49.8 % (250 mg Ca) from the baseline of 14.8 ug/dL, and 74.5 % (500 mg Ca) from the baseline of 14.1 ug/dL. This study found statistically significant inverse associations with dietary Ca supplementation and BLLs in young children. These findings suggest that calcium supplementation effectively lowers BLLs in school children.