ABSTRACT
The purpose of this article is to examine the current literature regarding the relationship between adverse childhood experiences (ACEs) and environmental exposures. Specifically, the paper will focus on how this relationship between ACEs and physical environmental factors impacts the neurocognitive development of children. With a comprehensive literary search focusing on ACEs, inclusive of socioeconomic status (SES), and environmental toxins common in urban environments, the paper explores how these factors contribute to cognitive outcomes that are associated with the environment and childhood nurturing. The relationship between ACEs and environmental exposures reveals adverse outcomes in children's neurocognitive development. These cognitive outcomes include learning disabilities, lowered IQ, memory and attention problems, and overall poor educational outcomes. Additionally, potential mechanisms of environmental exposures and children's neurocognitive outcomes are explored, referencing data from animal studies and evidence from brain imaging studies. This study further analyzes the current gaps in the literature, such as the lack of data focusing on exposure to environmental toxicants resulting from experiencing ACEs and discusses the research and social policy implications of ACEs and environmental exposure in the neurocognitive development of children.
ABSTRACT
BACKGROUND/AIMS: The association between social adversity and externalizing behavioral problems in children is well-documented. What is much less researched are biological mechanisms that may mediate such relationships. This study examines the hypothesis that low blood lead mediates the relationship between social adversity and child externalizing behavior problems. METHODS: In this cross-sectional study, participants were 131 children aged 11-12 years (mean = 11.90) from Philadelphia, US. A venous fasting blood sample was taken and analyzed for blood lead levels. A social adversity index was calculated based on 10 total indicators derived from a psychosocial interview of the parent and official neighborhood data, while child behavior outcomes (internalizing and externalizing behavior) were assessed using both parent-report and child self-report. RESULTS: The mean blood lead level was 2.20 µg/dL. Both relatively higher blood lead levels and higher social adversity scores were associated with higher levels of parent-reported and child self-reported externalizing behaviors. Additionally, blood lead mediated the relationship between social adversity and child-reported externalizing behavior (Indirect effect: B = 0.03, 95% CI: 0.004, 0.09) and partially mediated the relationship between social adversity and parent-reported externalizing behavior (Indirect Effect: B = 0.03, 95% CI: 0.01, 0.07). CONCLUSION: To our knowledge, this study is the first to suggest that blood lead levels play a mediating role in the relationship between externalizing behavior problems and social adversity. Findings have potentially important implications for public health and environmental regulation as well as understanding biological mechanisms that link social inequality with health outcomes, especially in youth from low-income, urban areas.
