Our scientific understanding of breast cancer and the environment has evolved rapidly in the last two decades. We’ve learned that low doses of some chemicals may increase risk to disease, that combinations of chemicals (mixtures) have different effects than single chemicals alone, and that there are distinct subtypes of breast cancer. We’re also beginning to understand the interaction between environmental exposures and genetic and social factors.
Glossary of Exposures
We’ve reviewed the evidence linking more than three dozen chemical and physical agents to breast cancer. For each, we explore the evidence and tips for avoiding the exposure.
Low dose effects and timing of exposures
Scientific evidence now shows that some chemicals, especially endocrine disrupting compounds, can exert negative effects at extremely low levels of exposure, sometimes with more serious or different effects than at higher doses. The timing, duration and pattern of exposure are just as important as the dose. While it’s good to limit exposure to toxic chemicals and radiation at every stage of life, it is even more important during critical periods, including gestation, childhood and pregnancy.
Mixtures and interactions
Repeated, low-dose exposures occur for an array of chemicals every day. Some chemicals are used in multiple products and may also be present in air and water, and many of the products we use routinely contain many chemicals of concern. The social and biological contexts in which those exposures occur are important for understanding breast cancer risk. Research suggests that exposure to different kinds of mixtures affects breast cancer risk, but only a small number of those combinations have actually been tested.
Cancer cells behave differently than normal, healthy cells and tissues. For a long time, cancer was thought to occur because of mutations in the genes (DNA) in individual cells. Newer understandings suggest that the picture is more complex.
Breast cancer subtypes
Breast cancer is not a single disease, and different cancer subtypes may be associated with different traditional risk factors.
Breast cancer statistics
Globally, breast cancer affects more women than any other type of cancer and is the leading cause of cancer-related deaths among women.
Hormone disruption and breast development
Low doses of EDC’s, especially during critical stages of development can increase the risk of adverse health effects including cancers, neurodevelopmental and neurodegenerative diseases, metabolic disorders, asthma and immune disorders.