Background: Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk.
Methods: Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk. We identified corresponding assays to develop the Hazard Identification Approach for Breast Carcinogens (HIA-BC), a method for detecting chemicals that may raise breast cancer risk. Finally, we conducted a literature-based pilot test of the HIA-BC.
Results: The HIA-BC identifies assays capable of detecting alterations to biological processes relevant to breast cancer, including cellular and molecular events, tissue changes, and factors that alter susceptibility. In the pilot test of the HIA-BC, chemicals associated with breast cancer all demonstrated genotoxic or endocrine activity, but not necessarily both. Significant data gaps persist.
Conclusions: This approach could inform the development of toxicity testing that targets mechanisms relevant to breast cancer, providing a basis for identifying safer chemicals. The study identified important end points not currently evaluated by federal testing programs, including altered mammary gland development, Her2 activation, progesterone receptor activity, prolactin effects, and aspects of estrogen receptor β activity. This approach could be extended to identify the biological processes and screening methods relevant for other common diseases.
1Center for Occupational and Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA; 2Silent Spring Institute, Newton, Massachusetts, USA; 3California Pacific Medical Center Research Institute, San Francisco, California, USA; 4Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA; 5Department of Nutritional Sciences and Toxicology, and 6Department of Environmental Health, University of California, Berkeley, Berkeley, California, USA; 7California Environmental Protection Agency, Sacramento, California, USA; 8Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California, USA; 9Division of Occupational and Environmental Medicine, University of California, San Francisco, San Francisco, California, USA; 10Natural Resources Defense Council (NRDC), San Francisco, California, USA
Recommended Citation:
Megan R. Schwarzman,1 Janet M. Ackerman,2 Shanaz H. Dairkee,et al. Screening for Chemical Contributions to Breast Cancer Risk: A Case Study for Chemical Safety Evaluation[J]. Environmental Health Perspectives,2015-01-01,Volume 123(Issue 12):1255