Environmental Factors Associated with Change of Blood Lead Levels in Children and Adolescents

Abstract

Objective: Low-dose lead exposure in childhood and adolescents affects health later in life. This study was conducted to determine the contribution of three environmental media (parental cotinine concentration, nutritional consumption and residential household environmental factors) to the blood lead level.

Methods: The study group consisted of 39 children and 40 adolescents, aged between 5 and 19 years. Children blood lead level in an industrial residence area was collected in the environmental health cohort survey conducted from 2005 to 2008.

Results: The overall mean blood lead level for the subjects was 1.28 μg/dL (95%CI 0.77-1.78). Blood lead levels were consistently higher for boys than for girls (B= -0.14409, P= 0.0017), for older children (B= 0.03827, p= 0.0027) than young children and for Shihwa city residents than Ansan residents (B= -0.58061, P= 0.0312). Blood lead levels was significantly correlated to maternal cotinine concentration (p=0.0270) but not to paternal cotinine concentration (p=0.2014) and subjects cotinine concentration (p=0.0931). This study examined the association between blood lead levels and dietary intake using multiple linear regression analysis. Calcium intake was observed to have a statically significant reverse relationship with blood lead levels (B -0.00083055, p=0.0093). Residential environmental factor and blood lead levels are associated with type of drinking water, type of heating, maternal education level after adjusting age, sex, and previous blood lead levels (two years ago). The final mixed model for repeated measurement of blood lead levels is associated with maternal cotinine levels and type of drinking water after adjusting family effect.

Conclusion: The subjects blood-lead levels were essentially linked to two factors: maternal cotinine levels and type of drinking water.