Risk Factors and Hazards in the Household Environment for Elevated Blood Lead Levels in Urban Preschool Children of Vellore: A Case–Control Approach in the MAL-ED Birth Cohort

To study the household environmental risk factors and hazards associated with elevated blood lead levels (EBLLs) in preschool children in an urban setting of Vellore, South India. A case–control study within the MAL-ED (Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development) birth cohort was conducted between January 2014 and January 2015. The study included 153 pre-school children: 87 cases and 66 controls with elevated and normal BLLs, respectively. A structured questionnaire was used to assess the sociodemographic profile, household environment, breastfeeding practices, children’s habits, and the use of cosmetics in them. Household environmental samples of wall and door paint, floor dust, drinking water, and cosmetics were estimated for lead levels using gas flame atomic absorption spectrometry (FAAS). Children born with low birth weight, those living in houses painted at least once in the last five years and those residing in houses older than ten years had a higher odds of EBLLs [OR (95% CI) = 3.79 (1.24–11.1); 4.84 (1.42–16.53); 5.07 (2.06–12.46), and 2.58 (0.99–6.69)], respectively. Drinking water samples from both cases (88%) and controls (95%) had lead levels more than the Environmental Protection Agency (EPA), USA recommendation of 0.015 ppm. Low birth weight and the household environment pose important risk factors/hazards for elevated blood lead levels in urban preschool children. Multipronged interventions that include government legislations, household environmental modification, safe water supply, and community education are pivotal in reducing lead exposure in young children.