10/21/2009 05:12 am ET | Updated Nov 17, 2011

The National Cancer Institute Should be on the Forefront of Identifying the Causes of Cancer

Samuel Epstein has been a respected, champion of environmental causes of cancer for many years but I must challenge his recent blog post here on HuffPost regarding the Love/Avon Army of Women.

It is certainly true that the chemicals mentioned in his piece have theoretical potential as causes of cancer, however almost all of the data comes from studies on cells and rats. This type of research is very useful in generating hypothesis but cannot prove cause and effect in women. For that we need studies in women. As has been well pointed out in the Breast Cancer Fund's State of the Evidence: The Connection Between Breast Cancer and the Environment, "We need to begin to think of breast cancer causation as a complex web of often interconnected factors, each exerting direct and interactive effects on cellular processes in mammary tissue." Studying one chemical at a time in cells or rats will not be able to predict what the effects in women might be. As one basic scientist said to me the problem with studying women is that "they are so messy and we can't control all the factors." But it is this messiness, or complex web of factors that leads to breast cancer. And it is only by studying women in all their complexity that we will be able to figure out all the causes of breast cancer. It was to this end that the Love Army of Women was launched with a generous grant from the Avon Foundation for Women. Over 330,000 women have signed up to be part of finding the answers by being willing to consider participating in research into the cause and prevention of breast cancer.

Could there be carcinogens in cosmetics that increase breast cancer risk? Of course! Should companies try to use the safest ingredients possible? Of course! In fact Avon is eliminating phthalates in response to the concerns of breast cancer advocates. Could they do more, undoubtedly but they also should be congratulated on funding research into all the possible causes of breast cancer even when the results may not be in its own corporate self-interest. And the National Cancer Institute should be congratulated for being willing to collaborate on new projects to find the answers once and for all.