The relationship between mental retardation and developmental delays in children and the levels of arsenic, mercury and lead in soil samples taken near their mother’s residence during pregnancy

Abstract

This study was designed to evaluate the association between lead, mercury, and arsenic in the soil near maternal residences during pregnancy and mental retardation or developmental disability (MR/DD) in children. The study was conducted using 6,048 mothers who did not move throughout their pregnancies and lived within six strips of land in South Carolina and were insured by Medicaid between January 1, 1997 and December 31, 2002. The mother child pairs were then followed until June 1, 2008, through their Medicaid reimbursement files, to identify children diagnosed with MR/DD. The soil was sampled for mercury (Hg), lead (Pb), and As based on a uniform grid, and the soil concentrations were Kriged to estimate chemical concentration at individual locations. We identified a significant relationship between MR/DD and As, and the form of the relationship was nonlinear, after controlling for other known risk factors.

Bayesian importance parameter modeling of misaligned predictors: soil metal measures related to residential history and intellectual disability in children

“…This research is motivated by a study of ID cases in children who were born to mothers who were pregnant, and insured by Medicaid, in South Carolina between 1996 and 2002 (Aelion et al 2009a, b; Kim et al 2009, 2010; Liu et al 2010; McDermott et al 2012, 2011; Zhen et al 2008). In our analysis, we included only the first child for each mother.…”

“…Studies in animals suggest that ingested inorganic arsenic may produce developmental effects at high doses that also produce overt maternal toxicity (Centers for Disease Control and Prevention 2007a). High levels of As have been found to increase the probability of ID in children (Liu et al 2010; McDermott et al 2012, 2011; Vahter 2009). There is evidence of an association between As in soil and the combined outcome of ID and developmental delay (McDermott et al 2011); however, there is no evidence of an association of As combined with other metals in soil and the outcome of ID (Liu et al 2010).…”

“…People are exposed to Pb via dust, old lead-based paints, drinking water, food, or drink. High soil concentration of Pb has been found to be associated with a higher probability of ID in children, and the Centers for Disease Control and Prevention now states that even low levels of Pb are a concern (Liu et al 2010; McDermott et al 2012). Mn is an essential nutrient, with small amounts necessary for normal body functioning; however, in excess, it can be detrimental to health.…”

Solid–liquid separation method governs the in vitro bioaccessibility of metals in contaminated soil-like test materials

“…Also, environmental exposures have occasionally been associated with adverse health effects in terms of biochemical variables, neurological endpoints, intelligence, verbal ability, long-term memory, activity disorders, and DNA damage in human populations http://dx.doi.org/10.1016/j.chemosphere.2014.12.019 0045-6535/Ó 2014 Elsevier Ltd. All rights reserved. (Ericson and Mishra, 1990;Baghurst et al, 1992;Sergeev and Carpenter, 2005;Liu et al, 2010;Wu et al, 2011;GaminoGutierrez et al, 2013;McDermott et al, 2014). These toxicological and epidemiological studies have underscored the obligation of regulatory agencies to monitor, mitigate, and remediate both current and legacy contaminated sites.…”

Associations of estimated residential soil arsenic and lead concentrations and community-level environmental measures with mother–child health conditions in South Carolina

“…In an ongoing study in South Carolina (SC), data from a cohort of Medicaid mother-child pairs were analyzed to assess intellectual disability (ID; previously classified as mental retardation) and developmental delay (DD) outcomes in children (Cai et al, 2011; Zhen et al, 2009; Zhen et al, 2008) and potential associations with soil metal concentrations (McDermott et al, 2011; Liu et al, 2010). Building upon those studies, we undertook an aggregate analysis of mother-child variables at the United States (US) Census 2000 block group level, and spatially interpolated soil As and Pb concentrations in case areas with significantly higher ID and/or DD prevalence rates, and in a control area with ID and DD prevalence rates similar to the state background rate.…”