CU asks FDA for full assessment on use of engineered nanoparticles

October 30, 2008
The Honorable Andrew C. von Eschenbach, M.D.
U.S. Food and Drug Administration
5600 Fishers Lane, Room 15-47
Rockville, MD 20857
Dear Dr. von Eschenbach:
We are writing to ask the FDA to require a full safety assessment on the use of engineered nanoparticles particularly in cosmetics, sunscreens and sunblocks, and to investigate possible enforcement action to ensure accurate labeling as to the presence or absence of nanoparticles. New findings published in Consumer Reports today confirm that use of certain nanoparticles is widespread in mineral-based sunscreens, and that company representatives are making erroneous assertions about these particles in their products.
Consumers Union began investigating nanoparticles in sunscreens in 2007. An article in the July 2007 Consumer Reports revealed that 8 out of 8 mineral-based sunscreens tested contained nanoparticles of zinc oxide and/or titanium dioxide. However, only one on them disclosed that fact on the label; the rest had no label disclosures (article attached).
Given that some consumers have expressed a desire to avoid products with nanoparticles, we set out in 2008 to purchase sunscreens that manufacturers said do not contain nanoparticles, and to test them to verify their assertions. In early 2008, we bought a number of sunscreens that contain titanium dioxide or zinc oxide (or both) focusing on products that, according to company representatives, did not contain nanoparticles. The December 2008 Consumer Reports contains the results of our testing (article attached). We found that four of the five companies’ statements to us about their products— Aubrey Organics Natural Sun SPF 25 Green Tea Protective Sunscreen, Badger SPF 30 Sunscreen, Kiss My Face SPF 30+ Sun screen, and Mexitan SPF 30 Sunscreen—asserting that they did not contain nanoparticles, were not correct. Each of these products was labeled natural or organic. Our commissioned test found nanoparticles of titanium dioxide and/or zinc oxide in all the sunscreens except Zinka Colored Nosecoat.
Thus, our two test projects suggest that use of nanoparticles of titanium dioxide and/or zinc oxide in mineral-based sunscreens is widespread and that consumers will generally not be able to avoid exposure by buying mineral-based products that manufacturers say do not contain nanoparticles.
Ensuring the safety of these products, which are widely used on children and adults, is therefore of paramount importance. Studies of macro-scale titanium dioxide and zinc oxide have long demonstrated their safety in a range of applications including drugs. By contrast, animal studies show that titanium dioxide nanoparticles can damage the lungs(1) . In vitro studies show that such nanoparticles can cause damage to nerve and brain cells(2) and damage DNA in a number of cultured cells(3). Whether, or under what conditions, nanoparticles of titanium dioxide or zinc oxide can be absorbed through the skin and whether dermal absorption is a prerequisite for adverse health effects are still open questions.
The European Union is sufficiently concerned about nanoparticles in sunscreen to be requiring a full safety assessment. The European Union’s Scientific Committee on Emerging and Newly-Identified Health Risks has clearly stated that size matters: “the behaviour of nanoparticles is critically dependent on several characteristics, including size, surface area and surface reactivity, and the risk assessments related to both human health and the environment have to be based on these characteristics.”(4) Furthermore, the EU’s Scientific Committee on Consumer Products issued an “Opinion on Safety of Nanomaterials in Cosmetics Products” late last year that stated “Review of the safety of the insoluble nanomaterials [e.g. titanium dioxide, zinc oxide] presently used in sunscreens is required.”(5) Indeed, on September 10, 2008, the European Commission asked companies to submit safety data “with regard to all substances used at nano-scale and the final [cosmetic] products in which they are used” by December 31, 2008, so that a full risk assessment can be performed.(6)
The EU has recognized that nanoparticles—including those of zinc oxide and titanium dioxide—used in sunscreens and other cosmetics may have different toxicological profiles/characteristics than larger versions of these materials, and therefore need to be assessed as to their safety, and have asked manufacturers to submit the data needed to conduct a full risk assessment. Given the apparent widespread use of these nanoparticles of titanium dioxide and zinc oxide in sunscreens in the US, as determined by our tests, we urge the FDA to do the same: to require safety assessment data on nanoparticles used in sunscreens. We also urge the FDA to require manufacturers to disclose the presence of nanoparticles on the label of any cosmetic or over-the-counter drug product that contain such particles, and to immediately investigate misstatements by manufacturers to Consumer Reports about absence of these nanoparticles in sunscreen products. Furthermore, we specifically urge the FDA to investigate whether the failure to disclose the presence of nanoparticles renders these sunscreen products misbranded, within the meaning of Section 201(n) of the Federal Food, Drug, and Cosmetic Act, codified at 21 U.S.C. § 321(n), in violation of 21 U.S.C. § 332(b).
Please contact me at 914-378-2452 if you have any questions or need additional information.
Michael Hansen, PhD
Senior Scientist
(1) Chen, HW, Su, SF, Chien, CT, Lin, WH, Yu, SL, Chou, CC, Chen, JJW and PC Yang. 2006. Titanium dioxide nanoparticles induce emphysema-like lung injury in mice. The FASEB Journal, 20: E1732-E1741. At:
(2) Long, TC, Tajuba, J, Sama, P, Saleh, N, Swartz, C, Parker, J, Hester, S, Lowry, GV and B Veronesi. 2007. Nanosize Titanium Dioxide Stimulates Reactive Oxygen Species in Brain Microglia and Damages Neurons in Vitro. Environmental Health Perspectives, 115(11): 1631-1637.
(3) Sayes, CM, Wahi, R, Kurian, PA, Liu, Y, West, JL, Ausman, KD, Warheit, DB and VL Colvin. 2006. Correlating Nanoscale Titania Structure with Toxicity: A Cytotoxicity and Inflammatory Response Study with Human Dermal Fibroblasts and Human Lung Epithelial Cells. Toxicological Sciences, 91(1): 174-185. At:
(4) pg. 13 in:
(5) pg. 4 in: