Seeing the Light on Darkness: Studies Link Light Pollution and Cancer
” recent study done in Israel headed by Richard Stevens, a professor and cancer epidemiologist at the University of Connecticut Health Center, and published in Chronobiology International, has shown some disturbing trends between women exposed to large amounts of artificial night light and breast cancer.
Stevens’ team overlaid satellite photos to measure nighttime artificial light levels with a map detailing the distribution of breast cancer cases. Those women living in the brightest areas (as defined by being able to read at outdoors at midnight) had a 73% higher risk of developing breast cancer than those living in areas with the least outdoor lighting.
These results correlate with an earlier study done in 2005 that showed women who worked night shifts in hospitals also had higher incidences of breast cancer. The report, published in Cancer Research, suggests that melatonin-or rather the lack of it-may be the cause. Melatonin is an essential hormone that our bodies make at night while we sleep. It requires darkness and plays a critical role in regulating our internal clocks. For women, the light-sensitive hormone is particularly important since scientists suspect that melatonin helps to reduce estrogen levels—higher estrogen levels being a factor in developing breast cancer. And melatonin levels drop precipitously in the presence of artificial light.”
April 01, 2009, 10:43am
