Although the United States does not have overarching regulations specific to nanomaterials yet, it is moving towards the control of nanoscale materials under the Toxic Substances Control Act (TSCA) and the National Institute for Occupational Safety and Health (NIOSH) has issued draft guidance on employee exposure. The US Environmental Protection Agency (EPA) has controlled and limited exposures to certain nanomaterials pursuant to its new chemical notice. These controls include limiting their use, requiring personal protective equipment, limiting environmental releases, and requiring testing.
Nanotechnology has been on the US government’s radar since at least 2001, when it launched the National Nanotechnology Initiative. In February 2007, the EPA published the Nanotechnology White Paper. The paper defined “nanotechnology” as “research and technology development at the atomic, molecular, or macromolecular levels using a length scale of approximately one to one hundred nanometers in any dimension; the creation and use of structures, devices and systems that have novel properties and functions because of their small size; and the ability to control or manipulate matter on an atomic scale.”
According to the White Paper, “nanotechnology has potential applications in many sectors of the American economy [… and] presents new opportunities to improve” the measuring, monitoring, managing, and minimization of contaminants in the environment. The EPA stated its interest in these benefits, but also its obligation “to protect human health and safeguard the environment by better understanding and addressing potential risks from exposure to nanoscale materials and products containing nanoscale materials”.
Since publishing the White Paper, the US has developed further studies and proposed rules, which may eventually have an impact on both environmental regulations and occupational health and safety (OHS) exposure limits.
Currently, on the environmental side, the EPA established that chemical manufacturers of carbon nanotubes must comply with the notification procedures of section 5 of the TSCA. Section 5 of the TSCA requires that any person manufacturing or importing a new chemical substance must file with the EPA a premanufacture notice (PMN). The EPA stated that it does not expect that all nanoscale substances will qualify as new chemicals under the TSCA. The EPA thus intends to determine whether nanoscale substances are new or existing chemical substances based on the case-by-case approach.
Additional environmental developments include proposed rules for single and multi-walled carbon tubes under TSCA, a petition for registration rulemaking requirements under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and the Nanoscale Materials Stewardship Program (NMSP).
EPA has also requested to classify nanoscale silver as a pesticide under the FIFRA. This would require formal pesticide registration of all products containing nanoscale silver, analysis of the potential human health and environmental risks of nanoscale silver, regulatory actions under the FIFRA against existing products that contain nanoscale silver, and other regulatory actions under the FIFRA as appropriate for nanoscale silver products. The EPA has not yet issued a proposed rule on this matter.
The EPA has published two proposed significant new user rules (SNUR) for carbon nanotubes. The first proposed SNUR would amend the TSCA and require persons who intend to manufacture, import, or process single-walled and multi-walled carbon nanotubes in an activity designated as a significant new use to notify the EPA at least 90 days prior to beginning the activity. The notice would provide the EPA with an opportunity to evaluate, and if necessary limit or prohibit the activity. Significant new uses under the proposed amendments for both multi-walled carbon nanotubes and single walled carbon nanotubes include:
– protection in the workplace;
– industrial, commercial, and consumer activities;
– release to water.
The second SNUR on carbon nanotubes addressed multi-walled carbon nanotubes specifically, and would amend the TSCA to include protection in the workplace and industrial, commercial, and consumer activities as significant new uses (subject to existing regulations).
The EPA is also developing rules under TSCA sections 8(a) and 4 to be proposed as SNURs by the end of 2010. The section 8(a) rule would require manufacturers of nanomaterials to provide “information including production volume, methods of manufacture and processing, exposure and release information, and available health and safety data.” The section 4 rule would “require testing for certain nanoscale materials that are already in commerce […], particularly [those] not already being tested by other federal and international organizations.”
On 25 May 2010, the United States Government Accountability Office (GAO) issued recommendations related to the regulation of nanomaterials, which would require companies to submit information to the EPA regarding use, manufacture and health and environmental risks of nanomaterials. Required information may include use of any nanoingredients in pesticides. Eventually, this information may be used to restrict use and manufacture of certain types of nanomaterials, including requiring protective equipment for workers, limits on discharges to waterways, product restrictions, etc. These recommendations will be considered by the EPA in forming future policy.
The EPA is also working with both domestic and international stakeholders, including the International Organization for Standardization and the Organization for Economic Cooperation and Development (OECD), with the aim of developing international standards for nanomaterials. Along with the OECD’s Working Party on Manufactured Nanomaterials (WPMN), the EPA lists the following nanoscale materials as representative for environmental health and safety testing:
– fullerenes (C60)
– single-walled carbon nanotubes (SWCNTs)
– multi-walled carbon nanotubes (MWCNTs)
– silver nanoparticles
– iron nanoparticles
– carbon black
– titanium dioxide
– aluminum oxide
– cerium oxide
– zinc oxide
– silicon dioxide
Potential nanotechnology regulation on the OHS side has been less pronounced. However, in 2007 the NIOSH issued a draft Current Intelligence Bulletin entitled, “Interim Guidance on Medical Screening of Workers Potentially Exposed to Engineered Nanoparticles.” The draft guidance concluded that no medical screenings of potentially exposed workers were warranted at the time. However it did recommend that workplaces take prudent measures to control workers’ exposure to nanoparticles; conduct hazard surveillance; and consider establishing medical surveillance. While no rules have yet been proposed in the OHS universe, it is possible that medical surveillance requirements may arise once further data is gathered.
Nanotechnology remains largely unregulated in the US, but the federal government is quickly moving in the direction of establishing controls and restrictions on such materials through environmental regulations under the TSCA and the FIFRA, and may develop occupational regulations as further medical surveillance data becomes available.