In the News
As published in 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. |