Headlines
As reported by the New Haven Register, July 23, 2006.
You’re Cooked: Sunscreens Don’t Block the Really Dangerous Rays
By Abram Katz
Americans have applied only partially effective sunscreen for almost
10 years although the U.S. Food and Drug Administration knew that the
products did not block dangerous radiation and sat on regulations that
could have corrected the problem, administration documents show.
Countless beach-goers and outdoorsmen have used sunscreen, believing
they were protecting themselves from solar ultraviolet rays, but most
sunscreens block only ultraviolet B rays and not ultraviolet A,
dermatologists said.
The B rays cause sunburn, while the A portion of the spectrum damages deeper layers of skin.
Overexposure to sunlight causes more than 1 million new cases of skin cancer every year in the United States. This includes 111,900 cases of melanoma, which kills about 8,000 people in the United States annually, according to the American Academy of Dermatology.
"People aren’t aware that sun protection factor (SPF) relates only to UVB," said Marla Campbell, associate clinical professor of pharmacy at the University of Connecticut Health Center.
"There are no standards for UVA. The FDA proposed label changes in 1999. The average consumer doesn’t know about this," she said.
Ultraviolet A, with a wavelength of 400 to 320 nanometers is less energetic than ultraviolent B, at 320 to 290 nanometers, but penetrates the skin more deeply. UVB causes sunburn. Visible light has a longer wavelength than ultraviolet.
Sunscreens able to deflect a broad spectrum of ultraviolet light should include avobenzone, oxybenzone, dioxybenzone, and/or zinc oxide, Campbell said.
One ounce of sunscreen should be applied every two hours, or more often if going swimming, she said.
This means that a 6-ounce tube of sunscreen may last a weekend, but not all summer, she said.
However, sunscreen alone does not provide a sufficient defense, said Dr. David J. Leffell, professor of dermatology and surgery at the Yale School of Medicine.
"People should practice sun protection. Stay out of the sun between 10 a.m. and 4 p.m., use a sunscreen with an SPF of 15 to 30 and reapply it every two hours. Wear a broad brimmed hat and sun protective clothing," Leffell said.
Meanwhile, products approved to defend against ultraviolet A and B have been delayed by uncertainty over how to measure the effectiveness of chemicals intended to block ultraviolet A radiation, the FDA contends.
Connecticut Attorney General Richard Blumenthal said that may be true, but it does not explain why companies have been allowed to keep putting false claims of "all day" protection against "all harmful rays" and being "waterproof" on their products.
Blumenthal sent a letter to the acting commissioner of the FDA two weeks ago urging him to put the abandoned sunscreen regulations into effect without delay. Congress requested the regulations in 1997 and they were published in the Federal Register in 1999.
"Ten years is a lot of time for people to be relying on misleading labels and false promises," Blumenthal said. "I am not a doctor, but I do know about regulations."
An FDA spokeswoman said amended and updated regulations will have to wait until this fall, at the earliest, when the FDA issues a new study of ultraviolet light testing and sunscreen labeling, including UVA.
Kimberly Rawlings, of the FDA, said the 42-page regulations were stayed in 1999 because they did not contain information about ultraviolet A light. "FDA had to resolve complex and scientific issues raised regarding the science of UVA," she said.
While the effects of UVB are clear and rapidly apparent — sunburned skin turns pink in response to solar damage — the impact of UVA becomes evident only after years or decades of exposure.
This makes testing for UVA more complicated.
However, UVA is important because it causes certain kinds of cancer and prematurely aged and wrinkled skin, dermatologists said.
The FDA "monograph" of 1999 refers to two agents, avobenzone and zinc oxide, that effectively absorb or scatter ultraviolet A. In the Federal Register of Sept. 16, 1996, "...The agency amended the proposed (monograph) to include avobenzone as a single ingredient and in combination with certain other sunscreen ingredients," the Federal Register of May 21, 1999, states.
The FDA, in the Federal Register of Oct. 22, 1998, "... proposed a specific skin damage and premature skin aging claim for sunscreen products containing specific concentrations of avobenzone or zinc oxide based upon the submission of data to support claims of UVA radiation protection in such products."
And that’s where the matter dropped, although the FDA apparently acknowledged that sunscreens should contain protection against ultraviolet A.
The FDA Consumer magazine of July-August 2000 states, "According to a 1998 review article, most sunscreens do not protect the skin from the longer UVA wavelengths. And that may be critical to the creation of skin cancer."
Rawlings said that since the 1999 rules were set aside, "the FDA has been resolving complex scientific issues and continuing to interact with the global, scientific and regulatory community to come to an understanding regarding the evolving science surrounding UVA."
Meanwhile, the U.S. Environmental Protection Agency unambiguously lists avobenzone and zinc oxide as two sunscreen ingredients that provide "extensive" protection against UVA — citing the FDA.
Dr. Philip Kerr, director of the melanoma clinic at the UConn Health Center, said there are two types of sunscreens, physical and chemical.
Zinc oxide and titanium dioxide reflect, absorb and block ultraviolet rays.
Current versions contain extremely small particles of the metal oxides, so that they are transparent and do not appear as opaque white.
Chemical screens include dozens of ingredients, including avobenzone, dioxybenzone, and similar compounds; cinnimates; homosalates; menthyl anthranilate; and octocrylenes in different combinations and proportions.
These chemicals absorb ultraviolet light and convert it to heat, said Dr. Kalman Watsky, dermatologist at the Hospital of Saint Raphael.
While SPF 50 sunscreen offers only a small percentage more protection than an SPF 30 product, the extra defense may be worthwhile for people especially sensitive to the sun, he said.