Environmental Contaminant Exposures and Preterm Birth: A Comprehensive Review

a Department of Environmental Health Sciences , University of Michigan School of Public Health , Ann Arbor , Michigan , USA.
Journal of Toxicology and Environmental Health Part B (Impact Factor: 4.97). 02/2013; 16(2):69-113. DOI: 10.1080/10937404.2013.775048
Source: PubMed


Preterm birth is a significant public health concern, as it is associated with high risk of infant mortality, various morbidities in both the neonatal period and later in life, and a significant societal economic burden. As many cases are of unknown etiology, identification of the contribution of environmental contaminant exposures is a priority in the study of preterm birth. This is a comprehensive review of all known studies published from 1992 through August 2012 linking maternal exposure to environmental chemicals during pregnancy with preterm birth. Using PubMed searches, studies were identified that examined associations between preterm birth and exposure to five categories of environmental toxicants, including persistent organic pollutants, drinking-water contaminants, atmospheric pollutants, metals and metalloids, and other environmental contaminants. Individual studies were summarized and specific suggestions were made for future work in regard to exposure and outcome assessment methods as well as study design, with the recommendation of focusing on potential mediating toxicological mechanisms. In conclusion, no consistent evidence was found for positive associations between individual chemical exposures and preterm birth. By identifying limitations and addressing the gaps that may have impeded the ability to identify true associations thus far, this review can guide future epidemiologic studies of environmental exposures and preterm birth.

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    • "Substances classified in category 2 include 5 mutagenic substances (M), 11 substances impairing fertility (RF), and 6 substances with developmental toxicity (RE). Lead and second-hand tobacco smoke only are classified in category 1 of substances causing developmental toxicity (RE), since evidence of an association between exposure to these agents and the risk of adverse pregnancy outcomes such as preterm birth and low birth weight is consistent [70-72]. The most common industrial uses of mutagenic and reprotoxic substances are related to the manufacture and/or use of adhesives, resins, additives, coatings, pigments, inks, polymers, papers, organic solvents, pesticides and woods and textiles. "
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