CSPH researchers are hopeful about untangling the web of factors that cause breast cancer. Prior to the 1990's, no one was willing to look at environmental risk factors. The research on physical activity is very promising and so is working with molecular markers. Things are very hopeful. Molecular Epidemiology Molecular biology is a relatively new field that has grown exponentially since the early 1980s when Environmental Health Sciences' Frederica Perera, Dr. P.H., led the first molecular epidemiologic study of cancer.
People react differently when exposed to carcinogens.
Some may be more or less able to activate a carcinogen than others. Similarly, certain individuals are better at detoxifying a carcinogen once it is activated or at repairing DNA damage. These genetically determined differences may be complicated by lifestyle factors, such as antioxidant vitamin levels. If you look at ten people who smoke a pack of cigarettes a day, only one or two will get cancer. In dust, water and soil, you can measure pesticides.