Iron deficiency increases blood lead levels in boys and pre-menarche girls surveyed in KNHANES 2010-2011

Introduction: We present data from the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-11 on the distribution of blood lead levels, and examine their association with iron deficiency in a representative sample of the adolescent Korean population. Methods: This study was based on data obtained from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. Serum ferritin was categorized into three levels: low (serum ferritin <15.0. μg/L), low normal (serum ferritin 15.0-30.0. μg/L for girls and 15.0-50.0 for boys), and normal (serum ferritin ≥30.0. μg/L for girls and ≥50.0 for boys), and its association with blood lead levels was assessed after adjustment for various demographic and lifestyle factors. Results: The geometric mean (GM) of blood lead in the low serum ferritin group was significantly higher than that in the normal group among boys but not girls. After controlling for covariates, multiple regression analysis showed that blood lead was inversely correlated with serum ferritin levels in boys and pre-menarche girls only. Discussion: The present study shows that iron deficiency increases blood lead levels in a representative sample of the male and pre-menarche female adolescent population, as evaluated in KNHANES. The confounding effect of estrogen on blood lead levels should be considered.