Blood Lead Levels of Primary School children in Kathmandu Municipality, Nepal

Abstract

Introduction: Lead is a toxic metal which has contaminated our environment and created health problems around the globe. Children are vulnerable to lead as the intake per unit body weight is higher and even low levels can cause neurological damage. Nepal lacks data on sources of lead exposure and its health impacts; hence screening of blood lead is mandatory.

Objectives: To determine blood lead levels, its associated risk factors and impact on health in primary school children in Kathmandu municipality, Nepal.

Methods: A total of 218 school children between 6-16 years age from Kathmandu were included in the study undertaken from November 2012 to June 2013. Consents were taken from guardians and students. Questionnaire was used to acquire data followed by blood sampling. Lead was measured using atomic absorption Spectrophotometer, hemoglobin and serum calcium was measured using commercial kits. Intelligent Quotient was assessed using serum form board. Data was analyzed using SPSS version 20.

Results: Overall, 63% (137) had detectable blood lead level (BLL) and 54% (117) had BLL ≥ 5 ug/dl. 55% were male and 45% female. The median BLL (IQR) was 8(0-34) and 4(0-18)b in males and females respectively. The mean hemoglobin and serum calcium was 13.7±2.4 and 8.1±1.8 respectively. On risk factors evaluation, the odds of having elevated blood lead level (EBLL) was significantly higher in children living in homes with chipping walls (p value 0.001). Children belonging to families with lower socioeconomic status (p value 0.001) and residing near traffic congested areas (p value 0.007). The median IQ was 73.5(66–91). EBLL showed significant negative correlation with IQ (p value 0.001). EBLL was identified as significant risk factor lowering IQ by 2.35 points per 10 ug/dl rise in blood.

Conclusion: Children living in homes with chipping walls, having lower socioeconomic status and residing near traffic congested areas had significantly higher lead level. EBLL showed significant negative correlation with IQ.