(Credit: Bigstock)

A rare moment of bipartisan agreement came last fall when Congress unanimously passed the Sunscreen Innovation Act, which President Obama promptly signed into law.

Lawmakers on Capitol Hill might not agree on federal budgets or trade bills, but members of both parties said the Food and Drug Administration needed to speed up its review of new and potentially better sunscreen ingredients, some of which have languished at the agency for more than a decade. While countries around the world have long had access to sunscreens that many dermatologists and cancer research groups say are more effective at blocking the sun's harmful rays, the United States has not expanded its list of approved sunscreen ingredients since 1999.

The Sunscreen Innovation Act mandated that the FDA work to reduce its backlog of applications, streamlined the existing review process and required the agency to report to Congress regularly on its progress. Cancer awareness groups, industry officials and some legislators who pushed for the new law believed it might finally break the logjam and that 2015 could be the summer when more advanced sunscreens arrived on American shores.

They were wrong.

Earlier this year, the FDA rejected all eight applications for new sunscreen ingredients pending at the agency, saying that companies such as BASF and L'Oreal must provide still more data before the products can be considered "generally recognized as safe and effective." That process could take months -- or even years -- but it certainly means no new-fangled sunscreens for U.S. consumers this summer.

[FDA review of sunscreen ingredients languishes, frustrating advocates]

The ongoing stalemate, perhaps not surprisingly, has exasperated people such as Sen. Johnny Isakson (R-Ga.), a principal backer of the Sunscreen Innovation Act, who said important new technologies are being held hostage by a painfully sluggish and overly rigid regulatory process.

"It's going way too slow. I'm very disappointed," Isakson, who himself has a history of melanoma, said in an interview.

That disappointment has been clear in Isakson's grilling of top FDA officials in recent months. "Can you tell me why the FDA is so reluctant to follow through on what Congress passed in the Sunscreen Innovation Act?" he asked the agency's then-commissioner, Margaret Hamburg, in March.

"Why do you do continue to delay in taking action? Some of those [applications] have been pending for 12 years," the senator asked Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, at a hearing last month.

The answer from Hamburg, Woodcock and other officials at the agency has been some variation of the following: We're frustrated, too. We're moving as quickly as we can and following deadlines set by the new law. But rules are rules, and the FDA can't abandon its standards and simply approve sunscreen ingredients that might not be entirely safe, even if they've been marketed in other countries for years.

Theresa Michele, director of the FDA's Division of Nonprescription Drug Products, said the agency has been transparent about how it is meeting the requirements of the new legislation, and that it has long made clear to companies with pending applications that it needs more information on which to base a decision.

"We're very committed to doing our part to provide consumers with additional options," Michele said in an interview. "But the sponsors also have to do their part to provide safety and efficacy data."

One key question for the FDA, Michele said, concerns the effects of regular sunscreen usage over time. She noted that decades ago people typically applied sunscreen sporadically or only when they hit the beach, but these days consumers are encouraged to use sunscreen anytime they are in the sun and to reapply every few hours. While that might help prevent damage from the sun, she said, regulators want to make sure there aren't other harmful effects over time from sunscreen being absorbed into the skin.

Michele also said that while the evaluation of new sunscreen ingredients is important, it's not the only work the FDA has done regarding sunscreen in recent years. She pointed to new rules announced in 2011 meant to cut back on misleading labels. For example, only products that meet the FDA standards for protecting against all types of ultraviolet rays can be labeled as providing "broad spectrum" protection. Likewise, the new regulations prohibit the use of terms such as "sweatproof" and "waterproof," because the FDA said such claims overstate their proven effectiveness. The agency also proposed limiting the maximum sun protection factor on labels to "50+," saying data didn't support claims that higher SPF offer greater protection.

Both UVA and UVB types of ultraviolet radiation from the sun can contribute to skin damage, premature aging and cancer. But UVA rays penetrate the skin more deeply, potentially damaging cells and contributing to the development of skin cancers.

In the United States, common UVA filters include chemicals such as oxybenzone and avobenzone. Those ingredients are effective, dermatologists say, but they either protect against only certain UVA rays or break down too quickly. Other UVA filters such as zinc oxide don’t break down as quickly but cover the skin in a white paste that can deter use. The pending applications at the FDA include chemical filters such as Tinosorb S, Tinosorb M and Mexoryl SX (also known as ecamsule), which experts say offer stronger and potentially longer-lasting UVA protection.

As the impasse over new sunscreen ingredients continues, Michele said Americans do have "access to a large number of sunscreen products" to help protect against skin damage, especially when combined with other measures, such as wearing protective clothing and seeking shade.

But others have excoriated the agency for the ongoing delay. In a recent editorial, the Wall Street Journal said the FDA's "willful culture of control and delay is the real public-health menace, and its sun-block blockade will surely lead to tens of thousands of needless melanoma deaths."

Attorney Michael Werner, a policy adviser to a coalition of doctors, cancer research foundations and manufacturers that lobbied for the Sunscreen Innovation Act, said he worries companies producing newer sunscreens might eventually give up on the U.S. market.

"FDA’s response is clearly a disincentive to innovate and bring innovative products to market in the United States," Werner said. "American consumers absolutely lose out."

According to the American Cancer Society, nearly 74,000 melanomas will be diagnosed this year in the United States, and nearly 10,000 people will die from the disease.