Shedding Light on a Cause of Breast Cancer
Posted on February 9, 2010 - Filed Under Air Pollution, Curbing Pollution, Environmental Pollution, General, Global Warming, Land Pollution, Ocean Pollution, Pollution News, Water Pollution |
When Edison invented the light bulb, did he accidentally spawn a cancer epidemic? It's certainly starting to look that way. In study after recent study, exposure to artificial light has been linked to certain kinds of tumors, especially those in the breast.
Consider some of the evidence: Blind women have low rates of breast cancer. So do women in underdeveloped countries, where artificial lighting is an uncommon luxury. By contrast, female nurses and other women who frequently work night shifts have high breast cancer rates. The reason, experts believe, is that their schedules expose them to illumination during what should be the darkest hours of their days, and that disrupts the body's production of the cancer-suppressing hormone melatonin. In lab experiments, human breast tumors have been found to grow relatively quickly when fed by the blood of women who have been in a brightly lit room in the middle of the night. When blood is drawn from women who've been sitting in darkness, it's richer in melatonin and less nourishing to the cancer.