While one is hard-pressed to name an industry that has not jumped on the nanotechnology bandwagon, the makers of cosmetics and sunscreens have capitalized on nanotechnology more aggressively than any other. The appeal of using nano-sized particles in sunscreens and cosmetics rather than their conventional counterparts comes from their small size — they can provide UV protection while remaining transparent, avoiding the pasty white appearance of conventional sunscreens. With cosmetics, nano-sized particles hold the promise to provide deep, targeted delivery of moisturizers to the living layers of skin. Makers of nano-cosmetics and nano-sunscreens not only acknowledge that they will penetrate the skin more deeply, but tout their health effects as well. With any new or powerful technology, there is the potential for bad along with the potential for good. However, the possibility for harm has been largely ignored by the U.S. Food and Drug Administration. Unlike the FDA's robust regulation of drugs, which requires drug makers to secure approval for marketing by showing safety and efficacy through human trials, cosmetics can be marketed without such proof. A raft of studies have now examined whether nano-sized particles penetrate or harm damaged or intact skin. These studies show that nano-sized particles have different toxicity because of their small size and high reactivity, and sometimes exert drug-like effects on the body. This emerging body of evidence calls into question the wisdom of leaving nano-sunscreens and nano-cosmetics largely unregulated. The weight of the evidence suggests that, at a minimum, questions about safety need to be asked — and answered. This Chapter shows that concerns over the safety of nano-cosmetics and nano-sunscreens have moved rapidly from the realm of speculation to grounds for real concern and, as a consequence, this regulatory void is no longer tenable or responsible. Part I demonstrates that many cosmetics and sunscreens use NPs. This Chapter explains the legal regulation of nano-cosmetics and nano-sunscreens, highlighting both Congress’ choice in the Food, Drug and Cosmetic Act, enacted in 1938, to subject cosmetics to far less scrutinizing than drugs and the FDA’s 1999 policy stance that nano-sunscreens pose no more risk than their larger counterparts. This Chapter then presents studies over the past decade that have shown that NPs, far from acting like SSPs, penetrate the protective outer layers of the skin to reach living tissues. There, NPs can cause oxidative stress, damaging cellular DNA. NPs also trigger structural changes and even programmed cell death in many cells they reach. Finally, in light of this evidence of biological impacts, this chapter calls upon the Congress and the FDA to revisit the laissez-faire regulation of nano-cosmetics and nano-sunscreens to better ensure the public’s safety
