The overall aim of this project is to identify suspect organic and inorganic chemicals during critical periods of intrauterine exposure that are associated with child developmental disabilities and mental retardation (DD/MR). The study will compare individual level analysis with new spatial and temporal statistical methods to infer from analysis of clusters to individuals about the risk associated with temporal and spatial exposures. The study will be divided into three phases. During Phase I we will test the hypothesis that there are clusters of DD/MR among infants identified by maternal residence during pregnancy. We will link over 152,000 maternal child pairs using Medicaid prenatal and postnatal medical data, and monthly addresses, so clusters of DD/MR can be identified using spatial statistics. During Phase II we will test the hypothesis that soil samples will show variation in toxicity levels that can be used to identify locations with potentially greater concentrations of suspect organic and inorganic chemical which may be associated with DD/MR. This will involve collecting and analyzing soil samples from cluster sites and from comparison areas where rates of DD/MR are not elevated. In addition, we will test the hypothesis that mercury, chromium, arsenic, PCBs, and other selected chemical contaminants will be measured in higher concentration in the higher toxicity soil samples compared to the lower toxicity soils, as identified using Microtox. We will send a subsample of the high and low toxicity soil for chemical analyses at an external analytical laboratory. During Phase III we will test the hypothesis that maternal residence proximal to toxic waste sites with identified chemical exposures, during critical periods of fetal development, will be associated with higher risk for DD/MR in the infant, after controlling for maternal and child risk factors. This will involve the development of statistical methods that combine traditional and spatial procedures to analyze associations between the spatial relationship, temporal exposure (month of pregnancy), and soil samples. These can be used to generate hypotheses about specific environmental exposures associated with DD/MR. This research will be both multidisciplinary and multimethod, with specific emphasis on the development of new techniques, to analyze the complex associations of environmental and medical data. ? ?

National Institute of Health (NIH)
National Institute of Environmental Health Sciences (NIEHS)
Research Project (R01)
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Study Section
Epidemiology of Chronic Diseases Study Section (ECD)
Program Officer
Gray, Kimberly A
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University of South Carolina at Columbia
Family Medicine
Schools of Medicine
United States
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Cai, Bo; Lawson, Andrew B; McDermott, Suzanne et al. (2016) A Bayesian semiparametric approach with change points for spatial ordinal data. Stat Methods Med Res 25:644-58
Davis, Harley T; Aelion, C Marjorie; Liu, Jihong et al. (2016) Potential sources and racial disparities in the residential distribution of soil arsenic and lead among pregnant women. Sci Total Environ 551-552:622-30
Davis, Harley T; Aelion, C Marjorie; Lawson, Andrew B et al. (2014) Associations between land cover categories, soil concentrations of arsenic, lead and barium, and population race/ethnicity and socioeconomic status. Sci Total Environ 490:1051-6
McDermott, Suzanne; Bao, Weichao; Aelion, C Marjorie et al. (2014) Does the metal content in soil around a pregnant woman's home increase the risk of low birth weight for her infant? Environ Geochem Health 36:1191-7
Onicescu, Georgiana; Lawson, Andrew B; McDermott, Suzanne et al. (2014) Bayesian importance parameter modeling of misaligned predictors: soil metal measures related to residential history and intellectual disability in children. Environ Sci Pollut Res Int 21:10775-86
Aelion, C Marjorie; Davis, Harley T; Lawson, Andrew B et al. (2014) Temporal and spatial variation in residential soil metal concentrations: implications for exposure assessments. Environ Pollut 185:365-8
McDermott, Suzanne; Bao, Weichao; Tong, Xin et al. (2014) Are different soil metals near the homes of pregnant women associated with mild and severe intellectual disability in children? Dev Med Child Neurol 56:888-97
Aelion, C Marjorie; Davis, Harley T; Lawson, Andrew B et al. (2013) Associations between soil lead concentrations and populations by race/ethnicity and income-to-poverty ratio in urban and rural areas. Environ Geochem Health 35:1-12
Lawson, Andrew B (2013) Commentary: Assessment of chance should be central in investigation of cancer clusters. Int J Epidemiol 42:448-9; discussion 455-6
Aelion, C Marjorie; Davis, Harley T; Lawson, Andrew B et al. (2012) Associations of estimated residential soil arsenic and lead concentrations and community-level environmental measures with mother-child health conditions in South Carolina. Health Place 18:774-81

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