Laboratory studies suggest that many of the chemicals found in our everyday lives may trigger breast tumors or hasten their growth, yet teasing out environmental clues to breast cancer is an extremely complex undertaking. We must estimate, for example, a woman’s exposure to chemicals years—or even decades—before her tumor first appeared. It is unlikely that any one study will bring dramatic breakthroughs. Rather, knowledge will build incrementally from many studies using multiple methods.
Those studies are desperately needed. Most breast cancer research has focused on detection and treatment rather than cause and prevention. Yet breast cancer remains the most common invasive cancer in women worldwide and each year more than 40,000 women in the United States alone die from the disease.
We often do not understand what factors put those women at risk of disease. Unexplained patterns of risk do contain a glimmer of hope, however. Breast cancer rates can rise—increasing over time, varying across regions, and changing as women move to new places. If we can understand why those rates increase, then we may be able to learn how to make them fall. This hope underlies the mission of Silent Spring Institute: to identify the links between the environment and women’s health, especially breast cancer.