Effects of elevated levels of Manganese and Iron in drinking water on birth outcomes

Abstract

We examined the impact of elevated levels exposure of pregnant women to manganese and iron through drinking water on singleton pregnancy outcome. We conducted an epidemiological study among 16 408 preg- nant women of Kaunas. We assessed each woman at her residence for exposure to manganese and iron levels measured in four Kaunas public water supply networks. We used a logistic regression to model the associa- tion between drinking water quality and birth outcomes controlling for the confounding variables. Analysis yielded increase in adjusted odds ratios (AOR) for term low birth weight (LBW) for moderate exposure level, 1.53 (95% confidence interval (CI) 0.89-2.66); and 1.70 (95% CI 1.07-2.71) for high exposure level. Maternal exposure was associated with a mean reduction of 21 g (SE, 9 g; p=0.02) in birth weight. No associations were observed between manganese and iron levels and preterm birth. These findings suggest that elevated levels of manganese and iron in drinking water are associated with a reduction in birth weight in term-born infants. However, further individual-level epidemiologic studies are necessary to investigate the factors that contribute to the increased sensitivity of some pregnant women.