Letters to the Editor
September 25, 2007Your article on tap water vs. bottled water (August-September) was generally right on target, but there is one misundrerstanding . The World Health Organization has stated that about 90% of all cancers are linked to environmental factors as opposed to genetic factors. Environmental factors relate largely to what we eat, smoke, and drink as well as viruses for some cancers, solar UV irradiances, and what we breathe. The large differences in cancer rates in different countries largely reflect different national diets, smoking rates, and alcohol consumption rates. While solar UV is a risk factor for skin cancers as well as lip cancer, maybe a couple more, solar UVB, through production of vitamin D, reduces the risk of at least 20 types of cancer. Those taking 1500-2000 IU of vitamin D3 per day can cut their cancer risk by 30-50%. As far as pollutants per se, they might account for 5-10% of all cancer. Pesticides, for example, are primarily risk factors for cancer for those working in agricultural fields without adequate protection, often in other countries such as Mexico. Pesticide applicators in the United States seem to have lower, rather than higher, cancer rates.
William B. Grant, Ph.D.
Sunlight, Nutrition, and Health Research Center
San Francisco
Copyright 2007 TheCityEdition.com
Editorial
