Association between arsenic, cadmium, manganese, and lead levels in private wells and birth defects prevalence in North Carolina: a semi-ecologic study

Abstract

BackgroundToxic metals including arsenic, cadmium, manganese, and lead are known human developmental toxicants that are able to cross the placental barrier from mother to fetus. In this population-based study, we assess the association between metal concentrations in private well water and birth defect prevalence in North Carolina.MethodsA semi-ecologic study was conducted including 20,151 infants born between 2003 and 2008 with selected birth defects (cases) identified by the North Carolina Birth Defects Monitoring Program, and 668,381 non-malformed infants (controls). Maternal residences at delivery and over 10,000 well locations measured for metals by the North Carolina Division of Public Health were geocoded. The average level of each metal was calculated among wells sampled within North Carolina census tracts. Individual exposure was assigned as the average metal level of the census tract that contained the geocoded maternal residence. Prevalence ratios (PR) with 95% confidence intervals (CI) were calculated to estimate the association between the prevalence of birth defects in the highest category (≥90th percentile) of average census tract metal levels and compared to the lowest category (≤50th percentile).ResultsStatewide, private well metal levels exceeded the EPA Maximum Contaminant Level (MCL) or secondary MCL for arsenic, cadmium, manganese, and lead in 2.4, 0.1, 20.5, and 3.1 percent of wells tested. Elevated manganese levels were statistically significantly associated with a higher prevalence of conotruncal heart defects (PR: 1.6 95% CI: 1.1-2.5).ConclusionsThese findings suggest an ecologic association between higher manganese concentrations in drinking water and the prevalence of conotruncal heart defects.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2458-14-955) contains supplementary material, which is available to authorized users.

Maternal arsenic exposure and nonsyndromic orofacial clefts

“…In contrast to the literature on occupational arsenic exposures, several studies have examined the relations between maternal exposures to arsenic‐contaminated drinking water and birth defects (Brender, Suarez, et al, 2006; Jin et al, ; Kwok, Kaufmann, & Jakariya, ; Mazumdar et al, ; Rudnai et al, ; Sanders et al, ; Zierler, Theodore, Cohen, & Rothman, ). Only one of these studies specifically examined OFCs (Sanders et al, ). The study examined arsenic levels in well water in North Carolina and reported a positive prevalence ratio for CL/P and an inverse prevalence ratio for CP; reported confidence intervals for each OFC subtype were consistent with the null.…”

Incorporating ToxCast and Tox21 datasets to rank biological activity of chemicals at Superfund sites in North Carolina

“…Interestingly, among the 29 contaminants present at >25% of North Carolina Superfund sites, 13 (45%) were metals or metalloids (Figure 2). Many metals are naturally occurring in North Carolina (Kim et al, 2011; Sanders et al, 2014, 2011; Spangler and Spangler, 2009), but are also used for various commercial purposes, including wood preservation, ingredients of dyes and pigments, and in production of electronics (Miller et al, 2016; Zeng et al, 2016). Also common among the chemicals frequently found at North Carolina Superfund sites were industrial organic solvents, such as trichloroethene and tetrachloroethene.…”

Modeling the Effects of Lead Pollution on Lactate Dehydrogenase Activity

“…The negative effects of these heavy metals on health, from the embryonic stage of development, and the linkage of environmental degradation, are being studied by scientists from different countries (Sanders et al, 2014;Ashley-Martin et al, 2018). At the same time, the mechanisms of both toxic and physiological action of lead to the present time are studied rather weakly and revealed much worse than for other trace elements.…”