The Causes of Breast Cancer: What Is Known?
There are few known causes of breast cancer, although there are numerous factors that have been identified as associated with a higher risk of developing the disease (Sasco 2001). One of the known causes of breast cancer is ionizing radiation, an environmental factor. There is also intense research into other possible environmental risk factors for breast cancer, including pesticide exposures, secondhand smoke, air pollutants, and estrogenic chemicals in the environment. Despite some excellent epidemiologic research, the scientific studies looking at breast cancer and environmental toxicants are extraordinarily conflicting, with a frustrating lack of clear, cohesive answers. The particularly conflicting nature of the breast cancer studies may have several explanations. Breast cancer is a multifactorial disease, meaning that many different genetic, lifestyle, and environmental factors contribute to the development of an individual case of cancer. This makes it difficult to pin down any
