Children's Health Advance Publication
Prenatal Organochlorine and Methylmercury Exposure and Memory and Learning in School-Age Children in Communities Near the New Bedford Harbor Superfund Site, Massachusetts
This EHP Advance Publication article has been peer-reviewed, revised, and accepted for publication. EHP Advance Publication articles are completely citable using the DOI number assigned to the article. This document will be replaced with the copyedited and formatted version as soon as it is available. Through the DOI number used in the citation, you will be able to access this document at each stage of the publication process.
Citation: Orenstein ST, Thurston SW, Bellinger DC, Schwartz JD, Amarasiriwardena CJ, Altshul LM, Korrick SA. Prenatal Organochlorine and Methylmercury Exposure and Memory and Learning in School-Age Children in Communities Near the New Bedford Harbor Superfund Site, Massachusetts. Environ Health Perspect; http://dx.doi.org/10.1289/ehp.1307804.
Received: 25 October 2013
Accepted: 24 July 2014
Advance Publication: 25 July 2014
Background: Polychlorinated biphenyls (PCBs), organochlorine pesticides, and methylmercury (MeHg) are environmentally persistent with adverse effects on neurodevelopment. However, especially among populations with commonly experienced low levels of exposure, research on neurodevelopmental effects of these toxicants has produced conflicting results.
Objectives: We assessed the association of low-level prenatal exposure to these contaminants with memory and learning.
Methods: 393 children, born between 1993-1998 to mothers residing near a PCB-contaminated harbor in New Bedford, Massachusetts were studied. Cord serum PCB, DDE, and maternal peripartum hair Hg levels were measured to estimate prenatal exposure. Memory and learning were assessed at age 8 (range: 7-11) years using the Wide Range Assessment of Memory and Learning (WRAML), age-standardized to a mean of 100 and standard deviation of 15. Associations with each WRAML index – Visual Memory, Verbal Memory, and Learning – were examined with multivariable linear regression, controlling for potential confounders.
Results: While cord serum PCB levels were low (sum of 4 PCBs, mean: 0.3 ng/g serum; range: 0.01, 4.4), hair Hg levels were typical of the U.S. fish eating population (mean: 0.6 µg/g; range: 0.3, 5.1). In multivariable models, each µg/g increase in hair Hg was associated with, on average, decrements of -2.8 on Visual Memory (95% CI: -5.0, -0.6, p=0.01), -2.2 on Learning (95% CI: -4.6, 0.2, p=0.08), and -1.7 on Verbal Memory (95% CI: -3.9, 0.6, p=0.14). There were no significant adverse associations of PCBs or DDE with WRAML indices.
Conclusions: These results support an adverse relationship between low-level prenatal MeHg exposure and childhood memory and learning, particularly visual memory.
New Search FunctionWe're pleased to present our improved search page. Try it, and let us know what you think!
CEHN September 2014 Article of the Month“Prenatal Polybrominated Diphenyl Ether Exposures and Neurodevelopment in U.S. Children through 5 Years of Age: The HOME Study” (Environ Health Perspect; DOI:10.1289/ehp.1307562) has been selected by the Children’s Environmental Health Network (CEHN) as its September 2014 Article of the Month. These CEHN summaries discuss the potential policy implications of current children’s environmental health research.
Register Today for PPTOX IVEnvironmental Stressors in Disease and Implications for Human Health
October 26–29, 2014
Boston Marriott Long Wharf Hotel
Join the Endocrine Society for the fourth international summit of Prenatal Programming and Toxicity (PPTOX), a premiere conference series dedicated to cutting-edge discussion of environmental hazards during early life and long-term consequences.* Housing deadline: Monday, October 6
For more information, visit the Endocrine Society website.
Sign Up to Receive E-mail Alerts
Recent Advance Publications
Structural and Functional Profiling of Environmental Ligands for Estrogen Receptors
Neurobehavioral Function in School-Age Children Exposed to Manganese in Drinking Water
Modeled PFOA Exposure and Coronary Artery Disease, Hypertension, and High Cholesterol in Community and Worker Cohorts
Characteristics of Walkable Built Environments and BMI z-Scores in Children: Evidence from a Large Electronic Health Record Database
Asthma in Inner-City Children at 5-11 Years of Age and Prenatal Exposure to Phthalates: The Columbia Center for Children’s Environmental Health Cohort