The role of geophagy and artisanal gold mining as risk factors for elevated blood lead levels in pregnant women in northwestern Tanzania

Abstract

Neither artisanal and small-scale gold mining (ASGM) or geophagy practices have received substantial attention related to blood lead levels despite the well documented deleterious effects of lead. This cross-sectional analytical study aimed to document the risk of lead exposure from geophagy and mining-related occupational activities for pregnant women. The study recruited 1056 pregnant women (883 in an ASGM area and 173 in a non-ASGM area) between April 2015 –April 2017. Generalized Linear Model with an identity link function was used to model the association between blood lead levels (BLLs) and geophagy practices and involvement in gold mining. The prevalence of geophagy was 36.2% (95% CI: 33.6, 39.4%) and 6.3% engaged in mining as a primary occupation. Practicing geophagy increased BLLs by 22% (β = 1.22, 95% CI: 1.116, 1.309, p<0.0001). Living in a gold mining area increased BLLs by 33.4% (β = 1.334, 95% CI: 1.2, 1.483, p<0.0001). Having mining as a primary occupation increased BLLs by 1.3% β = 1.013, 95% CI: 0.872, 1.176, p = 0.869) even though the association was not statistically significant. Socioeconomic wealth quantile (β = 1.037, 95% CI: 1.021, 1.054, p<0.001) increased blood lead levels by 3.7%. Developing a comprehensive inventory capturing sources of community-level lead exposure is essential. Further, increasing public health campaigns and education are crucial to limit geophagy practices and to minimize work in gold mining activities during pregnancy.