I never use sunscreen...everyone should consider not using it...
Free Radical Generators and Gender-Bending Estrogenic Chemicals
For decades, irresponsible cosmetic companies and a small group of very vocal, publicity-seeking dermatologists have strongly advocated that chemical sunscreens should be heavily applied before any exposure to sunlight, even on young children. They insisted that such sunscreen use would prevent skin cancer and protect your health. This was despite of a lack of any adequate safety testing of these chemicals. (It should be emphasized that most dermatologists are much more cautious and careful.)
On the other hand, over the past decade, many scientists studying cancer have come to virtually the opposite conclusion; that is, the use of sunscreen chemicals may be increasing the incidence of cancer and that sunlight exposure may actually decrease human cancer rates and improve your health.
It now appears that many heavily-used chemical sunscreens may actually increase cancers by virtue of their free radical generating properties. And more insidiously, many commonly used sunscreen chemicals have strong estrogenic actions that may cause serious problems in sexual development and adult sexual function, and may further increase cancer risks.
Adding to the problem is that large amounts of applied sunscreens can enter the bloodstream though your skin. In the 1970s, Prof. Howard Maibach warned that up to 35 percent of sunscreen applied to the skin can pass through the skin and enter the bloodstream but this had little effect on sunscreen promotion or safety testing. (Maibach, H. "NDELA-Percutaneous Penetration." FDA Contract 223-75-2340, May 19, 1978) The longer sunscreen chemicals are left on the skin, the greater the absorption into the body. (Bronaugh, R.L., et al. "The effect of cosmetic vehicles on the penetration of N-nitrosodiethanolamine through excised human skin, J Invest Dermatol; 1981; 76(2): 94-96.) This may be a factor in the large increases in cancer (breast, uterine, colon, prostate) observed in regions, such as Northern Australia, where the use of sunscreen chemicals has been heavily promoted by medical groups and the local governments.
Do Chemical Sunscreens Increase Cancer?
Worldwide, the greatest rise in melanoma has been experienced in countries where chemical sunscreens have been heavily promoted The rise in melanoma has been exceptionally high in Queensland, Australia where the medical establishment has vigorously promoted the use of sunscreens. Queensland now has more incidences of melanoma per capita than any other place on Earth. (Garland, Cedric F., et al. Could sunscreens increase melanoma risk? American Journal of Public Health, Vol. 82, No. 4, April 1992, pp. 614-15)
Many Common Sunscreen Chemicals are Strong Estrogens
er group tested six common chemicals that are used in sunscreens, lipsticks and facial cosmetics. Five of the six tested chemicals (benzophenone-3, homosalate, 4-methyl-benzylidene camphor (4-MBC), octyl-methoxycinnamate and octyl-dimethyl-PABA) behaved like strong estrogen in lab tests and caused cancer cells to grow more rapidly.
Schlumpf's group also found estrogenic sunscreens in the breast milk of mothers at levels of nanograms per kilogram of fat. This is the about same level as other known environmental contaminants such as PCBs. Schlumpf commented that this exposure could be dramatically increased in childhood by the large amount of sunscreen used by bathers, especially children. Her group is following the offspring of 4-MBC exposed rats to see if they develop health problems.
Based on these results, the Swiss researchers concluded that the impact of sunscreens containing these "endocrine disruptors" should be investigated more closely, in particular their penetration through human skin.