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Free Radical Generators & 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.
It is not that these compounds were ever viewed as benign substances. Organic chemists have been long aware of the dangers of compounds in chemical sunscreens. Such chemicals are widely used to start free radical reactions during chemical synthesis.
These chemicals are the dangerous types that one carefully keeps away from your skin while working in a laboratory. To use them, you mix them into a combination of other chemicals, then flash the mixture with an ultraviolet light. The ultraviolet absorbing chemicals then generate copious amounts of free radicals that initiated the desired chemical reactions.
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Chemical Sunscreens Are Free-Radical Generators
Most chemical sunscreens contain from 2 to 5% of benzophenone or its derivatives (oxybenzone, benzophenone-3) as their active ingredient. Benzophenone is one of the most powerful free radical generators known. It is used in industrial processes as a free radical generator to initiate chemical reactions. All chemical sunscreens absorb the ultraviolet radiation but this energy is trapped in the chemical and increases the chemical's reactivity.
Benzophenone is activated by ultraviolet light energy that breaks benzophenone's double bond to produce two free radical sites. It is also a fat-soluble chemical that easily passes through the skin's barrier and cell membranes and can enter the cell's interior where our fragile DNA resides. The free radicals then can initiate chain reactions which damage DNA and increase the risks of skin cancers.
Researchers at the Harvard Medical School have discovered that psoralen, another ultraviolet light-activated free radical generator, is an extremely efficient carcinogen. They found that the rate of squamous cell carcinoma among patients with psoriasis, who had been repeatedly treated with UVA light after a topical application of psoralen, was 83 times higher than among the general population.
Dr. Gordon Ainsleigh in California believes that the use of sunscreens causes more cancer deaths than it prevents. He estimates that the 17% increase in breast cancer observed between 1991 and 1992 may be the result of the pervasive use of sunscreens over the past decade2. Recent studies have also shown a higher rate of melanoma among men who regularly use sunscreens and a higher rate of basal cell carcinoma among women using sunscreens.
Dr. Martin Rieger reported that PABA may play a role in DNA-dimer formation, a type of DNA damage that can induce carcinogenic changes.
Most Chemical Sunscreens in the U. S. are Banned Elsewhere 
In 1997, Europe, Canada, and Australia changed sunscreens to use three specific active sunscreen ingredients - avobenzone (Parsol 1789), titanium dioxide, and zinc oxide - as the base.
In the US, the cosmetic companies have held off this policy as they try to sell off their stockpiles of cosmetics containing sunscreens banned in other countries. Many scientists have presented evidence that chemical sunscreens may increase your risk of cancers of the breast, ovaries, prostrate and colon.
Many common sunscreen chemicals also have estrogen-like effects. Margaret Schlumpf from the Institute of Pharmacology and Toxicology at the University of Zurich, Switzerland, found that they trigger developmental abnormalities in rats. Her research team tested six common UV screening chemicals used in sunscreens, lipsticks and other cosmetics.
All five tested UVB screens -benzophenone-3, homosalate, 4-methyl-benzylidene camphor (4-MBC), octyl-methoxycinnamate and octyl-dimethyl-PABA - acted like estrogen in lab tests and caused cancer cells to grow more rapidly. One of the most common sunscreens, 4-MBC, when mixed with olive oil and applied to rat skin, caused a doubling of the rate of uterine growth well before puberty.
"That was scary, because we used concentrations that are in the range allowed in sunscreens," said Schlumpf.
Why are Doctors Not Talking About This?
Despite the medical establishment's near unanimity on the issue of sunlight exposure, on other health issues in the past, serious errors been promoted to the public.
1.In 1927, 12,745 physicians endorsed smoking Lucky Strike cigarettes as a healthful activity. In the 1940s and 1950s, thousands of prominent surgeons were used in national cigarette advertisements to reassure the public about the safety of cigarette smoking.
2. In the 1950s, lobotomies were promoted for mental disorders and produced near-totally dysfunctional people.
3. In the 1960s and 1970s, diets high in omega-6 polyunsaturated fats and partially hydrogenated fatty acids such as safflower oil and margarine were recommended to reduce heart disease. However, long term studies found that, while such diets decreased heart disease, they increased the total death rate and the cancer rate and produced accelerated aging.
Physicians prescribed 15 to 30 minutes of sunlight twice daily and were warned not to start sunlight exposure too rapidly.