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Published on: March 29, 2018
Associations Between Disinfection By-Product Exposures and Craniofacial Birth Defects
John A Kaufman1, J Michael Wright, Amanda Evans
1Association of Schools and Programs of Public Health, hosted by U.S. Environmental Protection Agency, National Center for Environmental Assessment, Office of Research and Development, Cincinnati, Ohio (Mr Kaufman); National Center for Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, Ohio (Dr Wright); Campbell University, School of Osteopathic Medicine, Lillington, North Carolina (Ms Evans); Radiation Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey (Dr Rivera-Núñez); Independent Researcher, New York, New York (Ms Meyer); and National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina (Dr Narotsky).
Objective:
The aim of this study was to examine associations between craniofacial birth defects (CFDs) and disinfection by-product (DBP) exposures, including the sum of four trihalomethanes (THM4) and five haloacetic acids (HAA5) (ie, DBP9).
Methods:
We calculated first trimester adjusted odds ratios (aORs) for different DBPs in a matched case-control study of 366 CFD cases in Massachusetts towns with complete 1999 to 2004 THM and HAA data.
Results:
We detected elevated aORs for cleft palate with DBP9 (highest quintile aOR = 3.52; 95% CI: 1.07, 11.60), HAA5, trichloroacetic acid (TCAA), and dichloroacetic acid. We detected elevated aORs for eye defects with TCAA and chloroform.
Conclusion:
This is the first epidemiological study of DBPs to examine eye and ear defects, as well as HAAs and CFDs. The associations for cleft palate and eye defects highlight the importance of examining specific defects and DBPs beyond THM4.
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