br Conclusion br In summary the
In summary, the results from this study add to a small body of epidemiologic evidence that suggests PBDE exposures captured at middle age or older are not related to breast cancer risk. While our large study had substantially greater statistical power to detect effects than the prior two studies, it shares with those studies the primary limitation of reliance upon biomarkers of exposure that may not provide adequate estimates of chronic or early-life exposures. Furthermore, in our study we could not consider a number of factors that may be important modifiers of risks associated with these compounds, including poly-morphisms in Cytochrome p450 genes and other factors such as body fat that may affect endogenous AMG 925 levels.
Given the few epidemiologic studies conducted to date, none of which have been able to adequately address these methodologic lim-itations, it would be premature to conclude that PBDEs pose no risk for breast cancer. Further laboratory and epidemiologic investigations that can better address these outstanding issues are warranted given the ubiquitous human exposures to these compounds that are expected to persist for many decades.
This research was supported by funds provided by The Regents of the University of California, California Breast Cancer Research Program, Grant Number 16ZB-8501 and National Cancer Institute (NCI) of the National Institutes of Health (NIH), Grant R01 CA77398. The collection of cancer incidence data used in this study was supported by the California Department of Public Health pursuant to California Health and Safety Code Section 103885; Centers for Disease Control and Prevention’s (CDC) National Program of Cancer Registries, under cooperative agreement 5NU58DP006344; the National Cancer Institute’s Surveillance, Epidemiology and End Results Program under contract HHSN261201800032I awarded to the University of California,
San Francisco, contract HHSN261201800015I awarded to the University of Southern California, and contract HHSN261201800009I awarded to the Public Health Institute. The opinions, findings, and conclusions herein are solely the responsibility of the authors and do not necessarily represent the official views of the NIH, the California Department of Toxic Substances Control, the California Department of Public Health, the Regents of the University of California, or any of its programs.
Declarations of interest
We express our appreciation to all the participants in the California Teachers Study and to the phlebotomists, the researchers, analysts and staff who have contributed to the success of this research, including Hyoung-Gee Baek, Christine Duffy, Weihong Guo, Suhash Harwani, Megan Johnson, Minhthu Le, Sabrina Smith, Jane Sullivan-Halley, Yunzhu Wang and the California Teachers Study Steering Committee members who continue to work on other aspects of the CTS cohort, including Jessica Clague deHart, Dennis Deapen, James V. Lacey Jr., Eunjung Lee, Huiyan Ma, Hannah Park, Richard Pinder, Sophia S. Wang, and Argyrios Ziogas.
Appendix A. Supplementary data
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