By Wendee Nicole
Excerpt: In 2007 the National Academy of Sciences called for a paradigm shift in how chemicals are tested, recommending that toxicity testing look not just at disease end points such as tumors or birth defects but also at “upstream” events, meaning early changes in developmental processes that may later lead to disease. In this issue of EHP, a team of researchers apply that recommendation in a novel framework in which they work backward from a specific health outcome—in this case, breast cancer—through the biological mechanisms associated with it to identify appropriate assays for disease-specific chemical risk assessment.
The Hazard Identification Approach for Breast Carcinogens (HIA-BC) was developed by the University of California (UC) Berkeley Breast Cancer and Chemicals Policy project. An interdisciplinary panel of 18 scientists combed the breast cancer literature and cataloged molecular, cellular, and tissue changes that are strongly associated with the disease. These biological changes fell under three broad categories: endocrine disruption, alterations to mammary gland development, and processes generally associated with cancer, including cell cycle changes and genotoxicity (ability to cause DNA damage).
“We really have the chance, by improving the way we’re testing chemicals, to detect those that are setting us up for future disease,” says lead author Megan Schwarzman, a physician and environmental health researcher at UC Berkeley. “I’m eager to see the work continue, and continue relative to other diseases, so it can enrich the chemical testing being done on the national level.”