A new study shows that hundreds of common chemicals, including pesticides, ingredients in consumer products, food additives, and drinking water contaminants, could increase the risk of Breast Cancer by causing cells in breast tissue to produce more of the hormones estrogen or progesterone.
Ruthann Rudel, a toxicologist and research director at Silent Spring Institute and the co-author said that the connection between estrogen and progesterone and Breast Cancer is well established. So, we should be extremely cautious about chemicals in products that increase levels of these hormones in the body.
For instance, in 2002, when the Women’s Health Initiative study found combination hormone replacement therapy to be associated with an increased risk of Breast Cancer, women stopped taking the drugs and incidence rates went down. Rudel said that one of the most common therapies for treating is a class of drugs called aromatase inhibitors that lower levels of estrogen in the body, depriving Breast Cancer cells of the hormones they need to grow.
The goal of ToxCast is to improve the ability of scientists to predict whether a chemical will be harmful or not. The program uses automated chemical screening technologies to expose living cells to chemicals and then analyze the different biological changes they cause.Reporting in the journal Environmental Health Perspectives, Rudel and Cardona identified 296 chemicals that were found to increase estradiol or progesterone in cells in the laboratory. Seventy-one chemicals were found to increase levels of both hormones. The chemicals included components in personal care commodities such as hair dye, chemical flame retardants in building materials and furnishings, and several pesticides.