Chemical mixtures and neurobehavior: a review of epidemiologic findings and future directions
-
Ann M. Vuong
,
Kimberly Yolton
Abstract
Background
Epidemiological studies have historically focused on single toxicants, or toxic chemicals, and neurodevelopment, even though the interactions of chemicals and nutrients may result in additive, synergistic, antagonistic, or potentiating effects on neurological endpoints. Investigating the impact of environmentally-relevant chemical mixtures, including heavy metals and endocrine disrupting chemicals (EDCs), is more reflective of human exposures and may result in more refined environmental policies to protect the public.
Objective
In this review, we provide a summary of epidemiological studies that have analyzed chemical mixtures of heavy metals and EDCs and neurobehavior utilizing multi-chemical models, including frequentist and Bayesian methods.
Content
Studies investigating chemicals and neurobehavior have the opportunity to not only examine the impact of chemical mixtures, but they can also identify chemicals from a mixture that may play a key role in neurotoxicity, investigate interactive effects, estimate non-linear dose response, and identify potential windows of susceptibility. The examination of neurobehavioral domains is particularly challenging given that traits emerge and change over time and subclinical nuances of neurobehavior are often unrecognized. To date, only a handful of epidemiological studies examining neurodevelopment have utilized multi-pollutant models in the investigation of heavy metals and EDCs. However, these studies were successful in identifying contaminants of importance from the exposure mixtures.
Summary and Outlook
Investigators are encouraged to broaden their focus to include more environmentally relevant mixtures of chemicals using advanced statistical approaches, particularly to aid in identifying potential mechanisms underlying associations.
Funding source: Environmental Protection Agency
Award Identifier / Grant number: P01R829389
Funding source: National Institute of Environmental Health Sciences
Award Identifier / Grant number: P01 ES11261R01 ES014575R01 ES020349R01 ES024381R01 ES025214R01ES028277
Research Funding: National Institute of Environmental Health Sciences (P01 ES11261, R01 ES020349, R01 ES024381, R01 ES025214, R01 ES014575, R01ES028277) and Environmental Protection Agency (P01 R829389).
Author contribution: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: Authors state no conflict of interest.
Informed consent: Not applicable.
Ethical statements: Ethical statements are mandatory for original research that involved human or animal subjects.
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© 2020 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Editorial
- Assessing and mitigating environmental exposures in early life
- Mini Reviews
- Impact of pesticide exposure in childhood
- Risk of Mercury exposure during childhood: a review of Sri Lankan situation
- Methylmercury-induced pro-inflammatory cytokines activation and its preventive strategy using anti-inflammation N-acetyl-l-cysteine: a mini-review
- Multi-level analysis of symptoms of poison exposure reported to the Japanese Poison Information Center
- Review Article
- Chemical mixtures and neurobehavior: a review of epidemiologic findings and future directions
- Original Articles
- Human health risk assessment of heavy metals via consumption of fish from Kao Bay
- The relationship of mercury exposure with neurological problems in artisanal gold in Makassar city
- Contribution of house dust contamination towards lead exposure among children in Karachi, Pakistan
- Concentration of folic acid (FA) in serum of Japanese pregnant women
- Introducing the ORIGINS project: a community-based interventional birth cohort
- Effect of particulate matter 2.5 exposure to urinary malondialdehyde levels of public transport drivers in Jakarta
Articles in the same Issue
- Frontmatter
- Editorial
- Assessing and mitigating environmental exposures in early life
- Mini Reviews
- Impact of pesticide exposure in childhood
- Risk of Mercury exposure during childhood: a review of Sri Lankan situation
- Methylmercury-induced pro-inflammatory cytokines activation and its preventive strategy using anti-inflammation N-acetyl-l-cysteine: a mini-review
- Multi-level analysis of symptoms of poison exposure reported to the Japanese Poison Information Center
- Review Article
- Chemical mixtures and neurobehavior: a review of epidemiologic findings and future directions
- Original Articles
- Human health risk assessment of heavy metals via consumption of fish from Kao Bay
- The relationship of mercury exposure with neurological problems in artisanal gold in Makassar city
- Contribution of house dust contamination towards lead exposure among children in Karachi, Pakistan
- Concentration of folic acid (FA) in serum of Japanese pregnant women
- Introducing the ORIGINS project: a community-based interventional birth cohort
- Effect of particulate matter 2.5 exposure to urinary malondialdehyde levels of public transport drivers in Jakarta
