New FDA sunscreen rules called blind to nanotechnology

(Nanowerk News) The U.S. Food and Drug Administration's newly released sunscreen rules fail to meaningfully consider the risks posed by nanoscale ingredients, according to public interest groups including Friends of the Earth, The International Center for Technology Assessment and Consumers Union (ICTA).
"The FDA's new rule fails to address any of the concerns we raised five years ago in our legal petition," said George Kimbrell senior attorney at ICTA. "FDA's continuing failure to address these pressing health and environmental risks is extremely disappointing and unlawful."
Nanoscale ingredients are widely used in sunscreens to make the sun-blocking ingredients titanium dioxide (TiO2) and zinc oxide (ZnO) rub on clear instead of white. These materials have been shown to exhibit different fundamental physical, biological, and chemical properties than their larger counterparts. Very few nanomaterials have been adequately tested for safety, though the limited data available shows their small size enables them to enter the lungs, pass through cell membranes, and possibly penetrate damaged or sun-burnt skin.
"The FDA's new sunscreen standards miss the boat by ignoring this key health threat. The FDA has known about the threats posed by nanotech sunscreens for years, yet it refuses to regulate or require labelling for these products," said Ian Illuminato, health and environment campaigner at Friends of the Earth. "Why is it that the FDA continues to falter in protecting Americans' health?"
In 2006 ICTA filed a legal petition on behalf of consumer and environmental groups with the FDA insisting the agency issue specific regulations for nanotechnology and properly regulate the use of nanoscale ingredients in sunscreens. FDA has broad authority under the Federal Food, Drug and Cosmetic Act (FFDCA) over many nanomaterial products, including nanoscale ingredients in sunscreens and cosmetics. Despite the agency's lackluster guidance, FDA has yet to respond to ICTA's 2006 petition in full.
"Despite a separately released Guidance to Industry on nanotech products last week, FDA failed to connect the dots in its rule for over-the-counter sunscreens," said Colin O'Neil regulatory policy analyst for ICTA.
Whether or not nanomaterials readily penetrate human skin remains an important question, yet reason for concern has already been highlighted in the scientific literature. Isotope-labeled zinc used in nanoscale sunscreen ingredients can potentially reach the blood stream and urine of humans, suggests an Australian study by Macquarie University Professor Brian Gulson. This study undermines claims that nanoscale ingredients in sunscreens will stay on the outer layers of dead skin.
Michael Hansen, PhD, senior scientist at Consumers Union stated, "One of the main concerns with other studies conducted on nano skin penetration is that those studies were carried out in a short period of time — most studies only last 24 hours. This could be a reason why other studies have differed from the Gulson study."
In Gulson's study, the levels of isotope labelled zinc in the blood were still elevated after six days, suggesting the zinc may have been stored in reservoirs (e.g. hair follicles) and released over time. In addition, one of the test participants with sensitive skin had highly elevated levels, suggesting that a minority of the population may be at greater risk of skin penetration.
"Our government must promote research focused on the health and safety of nanomaterials and in the meantime protect the public from these ingredients. We are far from getting 'full-spectrum' protection from our regulators when it comes to sunscreens, the FDA rules will also allow other potentially toxic ingredients such as oxybenzone to remain in sunscreens," said Hansen.
France's health products safety agency (AFSSAPS) recently released a report and recommendations on TiO2 and ZnO as sunscreen agents. The report calls for further studies, and advises against the use of sunscreens containing nanoscale TiO2 on damaged or sunburnt skin. The report also recommends not using spray sunscreen containing nano TiO2 on the face or in closed premises. The FDA admits knowing little about nanomaterials and inhalation toxicity.
Nanoparticles do not have to enter a cell to be toxic — simple contact between nano-TiO2 and the cell membrane is enough to damage cell membranes in bacteria and crustaceans. Nano-TiO2 has also been demonstrated to cause cancer in mice. UCLA researchers suggest that the cancer was caused by genetic damage from the ingestion of nanoparticles and warn against occupational exposure to nanoparticles used in food colors, vitamins, and drug additives and spraying sunscreens containing TiO2 nanoparticles. Additional research has shown that nano-TiO2 can pass from pregnant mice to their offspring, causing functional and pathological disorders. Zinc oxide, in nano and conventional/bulk form, is not approved for use in cosmetics in the European Union due to inherent toxicity.
Source: International Center for Technology Assessment