Childhood Blood Lead Levels and Environmental Risk Factors in Madagascar

Abstract

One-third of children globally have blood lead levels (BLLs) exceeding the US CDC reference value of 5 µg/dL; this value may be as high as one-half for children in low- and middle-income countries (LMICs). Lead exposure occurs through a variety of routes (e.g., water, dust, air), and in LMICs specifically, informal economies (e.g., battery recycling) can drive lead exposures due in part to absent regulation. Previous work by our team identified a ubiquitous source of lead (Pb), in the form of Pb-containing components used in manually-operated pumps, in Toamasina, Madagascar. Characterization of BLLs of children exposed to this drinking water, and identification of additional exposure routes were needed. BLLs were measured for 362 children (aged 6 mo to 6 yr) in parallel with surveying to assess 14 risk factors related to demographics/socioeconomics, diet, use of pitcher pumps, and parental occupations. BLL data were also compared against a recent meta-review of BLLs for LMICs. Median childhood BLL (7.1 µg/dL) was consistent with those of other Sub-Saharan African LMICs (6.8 µg/dL) and generally higher than LMICs in other continents. Risk factors significantly associated (p<0.05, univariate logistic regression) with elevated BLL (at ≥5 µg/dL) included male gender, living near a railway or major roadway (owing potentially to legacy lead pollution), having lower-cost flooring, daily consumption of foods (beans, vegetables, rice) commonly cooked in recycled aluminum pots (a previously identified lead source for this community), and a maternal occupation (laundry-person) associated with lower socioeconomic status. Findings were similar at the ≥10 µg/dL BLL status. Our methods and findings may be appropriate in identifying and reducing lead exposures for children in other urbanizing cities, particularly in Sub-Saharan Africa, where lead exposure routes are complex and varied owing to informal economics and substantial legacy pollution.

Convergence of Social Marketing and Engineering: A Lead Mitigation Study in Madagascar

“…Prior studies in Toamasina have found that approximately one-third of the pitcher pumps with leaded components exhibit lead concentrations above the WHO provisional drinking water guideline of 10 µg/L (Buerck et al, 2021). In turn, exposure from cooking and drinking this water results in around 34% of children ages one to five with blood lead level (BLLs) concentrations of over 5 µg/dL, a level at which point irreversible health consequences occur (ACCLPP, 2012; Buerck et al, 2021; Champion et al, 2022; World Health Organization, 2010, 2019).…”