Some Comments on the Current State of Nanotechnology and the Consumer
The nanotechnology field is experiencing incredible growth. Nanotechnology is incorporated into products as diverse as paints, coatings, sporting goods, sunscreens, cosmetics, personal care products, stain-resistant clothing, food and food packaging. Nanomaterials are scientifically intriguing and potentially paradigm-shifting because the physio-chemical properties of these particles are fundamentally different from the corresponding bulk material. The number of nanopatents has risen exponentially. In 1980, there were 19 (total) such patents issued by the US, Europe and Japan, by 2008 the total had risen to 12,000 approved nanotechnology patents (H. Chen, M. C. Roco, X. Li and Y. Lin, Nature Nanotechnology 3, (2008) 125). The potential for patent infringement disputes is obvious. Other legal issues have arisen based on perceived environmental or health issues. Rick Weiss, a Senior Fellow at the Center for American Progress and Science Progress, (http://www.scienceprogress.org/2009/02/the-big-business-of-nano-litigation/) stated: “Whether it’s about suing or being sued, it seems that nanotechnology—and every other new technology with a still-uncertain benefit-to-risk ratio—is a 21st century Full Employment Act for attorneys”. The absence of federal regulation, discussed in detail below, means that we are essentially in a free-for-all situation. For example, some experiments have drawn parallels between the health issues of asbestos and the potential problems of carbon nanotubes. It has been strongly suggested by several groups that multiwalled carbon nanotubes could mimic asbestos and induce mesothelioma in those who suffer inhalation exposure. Recent research (Jessica P. Ryman-Rasmussen, et al, Nature Nanotechnology 4, (2009) 747) casts some doubt on a direct parallel. However, the uncertainty in all nanotechnology toxicity experiments arises here as well. Nanotubes did cause pathology in mice, however, the exact effects differed from those observed in asbestos-derived mesothelioma. The authors of this report note that this pathology maybe a reflection of mice physiology, rather than an inherent effect of nanotube exposure and that it might also reflect the impurities present in nanotubes produced by different techniques using different catalysts.
Nanotechnology-derived consumer products are in something of a regulatory vacuum. While aware of the need to consider the development of appropriate laws and certifications, the actual implementation of regulations by the relevant agencies is often stymied by the scientific inability to accurately define the material under consideration. Meanwhile, some environmental groups call for outright bans on the release of any nanoparticle-containing product. In many ways, such a call is fruitless, as we are exposed to many nanoparticles, both natural and man-made, everyday, and none of these particles are part of a particular consumer product, but rather the result of our way of life; soot, for example, contains nanoparticles of carbon.
One federal agency grappling with the classification of nanomaterials is the EPA, charged with regulating new substances under the Toxic Substance Control Act. Several sessions involving interested (see, for example, EPA Peer Consultation September 6-7, 2007; http://www.epa.gov/oppt/nano/mc09072007-mtgsummary.pdf) parties, including this writer, were held as part of an effort to decide whether to classify nanomaterials as a variant of current (macro) materials, carbon vs. nanotubes, or as new materials. The goal of these sessions was to collect comments on descriptions of nanomaterials, properties of potential interest, characterization data and data gaps. Experts at these sessions made it clear that, in many cases, each nanomaterial is a separate entity. That is, for example, nanotubes from different producers have different properties depending upon the production technique. At one level, that observation could require a separate regulatory response to every commercial nanomaterial; clearly, an unworkable solution. The EPA Voluntary Nanoscale Materials Stewardship Program began soon after these meetings in January, 2008, and ended recently. An interim report has been made publicly available on the EPA website (http://www.epa.gov/oppt/nano/nmsp-interim-report-final.pdf). Thirty-one companies submitted data on 132 materials during this period. Non-confidential portions of this material are available on the EPA website. At this point, the EPA is beginning to develop procedures through the use of Significant New Use Regulations (SNUR) (http://www.epa.gov/oppt/nano/index.html): “The Agency is developing a SNUR under section 5(a)(2) of TSCA ... The SNUR would require persons who intend to manufacture, import, or process certain nanoscale materials for an activity that is designated as a significant new use to submit a Significant New Use Notice (SNUN) to EPA at least 90 days before commencing that activity…The SNURs would provide the Agency with a basic set of information on nanoscale materials…would help the Agency evaluate the intended uses of these nanoscale materials and to take action to prohibit or limit activities that may present an unreasonable risk to human health or the environment. As part of the Agency's efforts to ensure a more comprehensive understanding of nanoscale materials that are already in commerce, EPA is also developing proposed rules under TSCA section 8(a) to require the submission of additional information, and under TSCA section 4 to require testing for nanoscale materials of particular interest, which are already in commerce…EPA anticipates proposing these rules by the end of 2010”. The EPA has issued two SNURs (http://www.epa.gov/oppt/nano/index.html#existingmaterials) dealing with multiwalled carbon nanotubes (MWCNT). The SNURs would identify existing uses of nanoscale materials based on information submitted under the Agency's voluntary stewardship program.
The FDA is a second federal agency in a similar regulatory situation; nanomaterials are already included in drugs or other products regulated by this agency, but the FDA is still in the process of developing an approach to the assessment of new nanomaterial-containing product safety. In fact, the largest category of known nanomaterial-containing products is the health and fitness category, including sunscreens, cosmetics and personal care products. In addition, there are a number of nanotechnology delivered drugs currently in use. Generally Regarded as Safe (GRAS) products or ingredients do not necessitate FDA review; however, these products are designated GRAS by the manufacturers subject to FDA review. The Government Accounting Office (GAO) has considered FDA oversight of nanomaterials as part of a general review of FDA procedures. The GAO report provided the following recommendation (GAO-10-246 February 3, 2010; http://gao.gov/products/GAO-10-246): “To better ensure FDA's oversight of the safety of GRAS substances, the Commissioner of FDA should develop a strategy to help ensure the safety of engineered nanomaterials that companies market as GRAS substances without the agency's knowledge, including taking steps such as issuing guidance recommended by the agency's nanotechnology taskforce, developing an agency definition of engineered nanomaterials, and requiring companies to inform FDA if their GRAS determinations involve engineered nanomaterials”. The FDA has established an internal task force to consider how to proceed. However, Congress is pushing the issue more strongly. Senators Pryor and Cardin introduced Senate Bill S. 2942 that would establish, with $25 million over each of the next five years, a program “to assess the health and safety implications of nanotechnology in everyday products…” Up to this time, the agency has not moved on its own to establish such a program.
The inability to accurately define the nanotechnology under regulatory consideration goes even as far as the need to ascertain whether a nano-labeled product contains any nanotechnology component at all. The first nano-scare involved a German product called “Magic Nano”, an aerosol bathroom cleaner (Rick Weiss, Washington Post April 6, 2006). The product was recalled after approximately 100 people reported respiratory problems, several requiring hospitalization. This experience provided a two-fold lesson: (1) it may be fashionable to label a new product as “Nano-X” whether or not it includes nanoparticles, but such a label must come with the realization that it invites additional scrutiny and (2) one must be certain of the final state of the consumer product. In this particular case, the spray was determined to be nanoparticle-free; minor adjustments to the chemistry caused silanes, which were expected to form nanoparticles, to deposit on the bottom of the spray can. The company, at the same time as attempting to create a “nanoformulation”, switched to an aerosol spray from a previously employed pump spray. This delivery change resulted in a finer mist that remained airborne for a longer time (Howard Wolinsky, European Molecular Biology Organization Reports, Vol. 7, Issue 9, p. 858). The aerosol released by the consumer using the spray was simply a fine mixture of ethanol and water and excessive spraying caused irritation by inhalation of the alcohol, not by inhalation of nanoparticles. This incident led, not unexpectedly and prior to a study of the chemistry, to a call for greater regulation of nanotechnology products. It also led to a hunt for class action lawsuit clients (http://www.lawyersandsettlements.com/case/magic_nano_recall.html). As noted in the San Francisco Chronicle’s online website, “…no industry -- including the nanotechnology industry -- is beyond the reach of American trial lawyers…” (SFGate.com: Keay Davidson October 31, 2005).
Nanometer-sized silver particles have emerged as, perhaps, the leading edge of nanotechnology in consumer products. The Project on Emerging Nanotechnologies (http://www.nanotechproject.org/) lists 235 consumer products containing nanometer dimensioned silver particles. This emergence has resulted from the antimicrobial properties of the material. The antimicrobial effects differ substantially from those brought about by antibiotics, supposedly eliminating the potential for microbial resistance and the applications of silver particles seem endless. Products as diverse as kitchen appliances, clothing, cutting boards, toothpaste and hairbrushes are included on the list of products, produced primarily in Asia. There is some preliminary research that suggests that these silver particles could have an impact on the immune response (http://www.sciencenews.org/view/generic/id/38913/), but more extensive research is required to confirm these results. There are vocal opponents of the widespread adoption of this nanotechnology without additional proof of its safety. These groups (see, for example, Friends of the Earth; http://www.foe.org/) cite both potential human health effects and a perceived uncertainty regarding the environmental fate of this nanomaterial. However, other groups (see, for example, the industry sponsored Silver Nanotechnology Working Group; http://www.silverinstitute.org/snwg.php) support widespread application of the technology, citing that the material “has been used in a wide range of consumer applications such as swimming pool treatments and drinking water filters with an established record under FIFRA (Federal Insecticide, Fungicide, and Rodenticide Act) of regulated and safe use dating as far back as the 1950’s… nanosilver is not a “new” material requiring some type of special regulation and EPA needs to look beyond general conceptions of nano terminology and consider the broader established regulatory record of nanoscale silver products within the Agency”. For its part, the Scientific Advisory Panel of the EPA has released a report that recommends that the EPA treat nanoparticle silver (http://www.epa.gov/scipoly/sap/meetings/2009/november/110309ameetingminutes.pdf) differently from “conventional” silver and require more extensive data to approve new applications for nanosized silver pesticide materials. The disagreement will certainly continue for some time.
A prevalent use of nanoparticles in the health and fitness category is in sunscreens. A Scientific American article that is now more than three years old (David Biello, Scientific American, August, 2007: http://www.scientificamerican.com/article.cfm?id=do-nanoparticles-and-sunscreen-mix) notes that of 38 participating companies in a survey, 29 used nanoparticles in their sunscreen formulation. Titanium dioxide (TiO2) and zinc oxide (ZnO) are effective sunscreens that work by blocking a wide spectrum of light. Macroscopic formulations of these metal oxides leave a white-colored layer on the skin. The smaller particles are invisible; the nanoparticles are even more effective at scattering light than larger particles. In Australia, the Therapeutic Goods Administration estimates that 70% of sunscreen products containing nanoparticles use TiO2 and 30% contain ZnO. The FDA has concluded that there is no evidence that nanoparticle formulations of sunscreen are unsafe. However, many groups have opposed the use of nanoparticle sunscreen formulations noting that zinc, for example, may penetrate the skin and that nanoparticles promote the formation of free radicals that may cause DNA damage (see, for example, Friends of the Earth, Australia: http://www.foe.org/healthy-people/nanotechnology-and-sunscreens). Peer-reviewed research has shown that ZnO nanoparticles may be absorbed through the skin, but that the amount absorbed was less than the recommended dietary intake of zinc (B. Gulson, et al, Toxicology Letters, Vol. 180S, (2008) S32). The potential danger of skin cancer has led at least one environmental group to endorse the sunscreens, declaring them (http://www.ewg.org/cosmetics/report/sunscreen09/investigation/Nanotechnology-Sunscreens) safe and effective. This controversy will not end anytime soon.
By reviewing the current state of regulatory affairs and considering the controversy arising from just several examples of consumer products, it is clear that careful consideration of the ingredients in nanoparticle formulations is a necessity. Moreover, public perception must be considered, as well as legal implications. In addition, although not discussed in this essay, the potential for litigation based on the number of issued patents is tremendous. Once a successful product is introduced, comparisons will be made to a range of related patents. The need for scientific scrutiny is obvious.