With uncharacteristic speed and remarkable clarity, the U.S. Environmental Protection
Agency (EPA) National Pollution Prevention and Toxics Advisory Committee (NPPTAC)
forwarded to EPA Administrator Stephen L. Johnson on November 22, 2005, its document
entitled Overview of Issues for Consideration by NPPTAC.
The Overview of Issues document sets forth NPPTAC’s “analysis and views” on a framework for a voluntary program on existing engineered nanoscale materials. The framework is intended to complement the new nanoscale chemicals requirements promulgated under the Toxic Substances Control Act (TSCA).
This column describes the voluntary nanoscale program outlined in the overview document, and discusses some of the challenging policy and technical issues facing EPA in implementing the program and regulating (under TSCA) new engineered nanoscale materials consisting of chemical substances. A prior installment of this column offers additional background on issues surrounding nanoscale materials.(1)
Background: The Promises and Pitfalls of Nanotech
EPA is very much aware of the promise of nanotechnology, and equally aware of potential risks to human health and the environment posed by engineered nanoscale materials. The Agency program office now most engaged in the regulatory implications of engineered nanoscale materials is EPA’s Office of Pollution Prevention and Toxics (OPPT), the office tasked with implementing TSCA and regulating existing and new chemical substances. Since engineered nanoscale materials consisting of new chemical substances are subject to EPA approval before they are manufactured or imported into the United States, EPA’s authority under TSCA is very much in the regulatory foreground.
EPA formally initiated its nanoscale materials TSCA regulatory explorations on May 10, 2005, when OPPT issued a Federal Register notice announcing its decision to convene a public meeting to assess the feasibility and wisdom of establishing a voluntary program on existing nanoscale materials consisting of chemical substances.(2)
The decision to convene such a meeting and to develop a voluntary reporting program was prompted, in part, by growing recognition that:
- engineered nanoscale materials consisting of chemical substances are finding their way into many commercial applications, including coatings, clothing, computers, cosmetics, and medical devices,
- some nanoscale materials have entered one or more of EPA’s various regulatory review processes, and
- the Agency needs a comprehensive and cogent risk assessment process that is able to identify, characterize, and manage risks that may be associated with nanoscale materials consisting of chemical substances.
While much has been written about the inherent promise of nanotechnology, particularly the use of nanoscale materials for environmental remediation, much less is known about the human health and environmental effects of engineered nanomaterials and structures.
What is known has given some cause for concern. According to a recent paper prepared
by the International Life Sciences Institute Research Foundation/Risk Science Institute, “the
existing research raises some concerns about the safety of nanomaterials and has led to increased
interest in studying the toxicity of nanomaterials for use in risk assessment and protection of
human health and the environment.”(3)
EPA is also aware of critically important legal/regulatory policy issues under TSCA with significant implications that need to be resolved. For example, much of the appeal of engineered nanoscale materials is their ability to impart novel physical and chemical properties that enhance certain functionalities and improve commercial appeal. Nano-sizing a material may enhance its conductivity, reactivity, luminescence, or some other physical or chemical attribute.
A core issue that OPPT is now trying to address involves the difference between new and existing substances under TSCA. “Existing” chemical substances (i.e., listed on the TSCA Inventory) may be nano-engineered to impart unique physical or other characteristics that may cause the nanoengineered substance to pose risks that are not associated with its bulk form. The issue is when might these characteristics or other changes to the chemical substance cause the substance to be sufficiently different from its bulk counterpart to make it a “new” chemical such that TSCA Section 5 is triggered, giving the Agency authority to obtain pre-market approval of the nanoengineered chemical.
EPA and others question, however, whether the Agency actually has sufficient
information to make distinctions between “new” and “existing” nanoscale materials for TSCA
regulatory and definitional purposes. This is one of the many reasons EPA is seeking to develop
quickly a voluntary nanomaterials program.
Many believe that it is important that EPA demonstrate clearly its ability under TSCA to
review and assess nanoscale materials and ensure that they pose no unreasonable risk to human health and the environment, as TSCA requires. Without sufficient toxicological and environmental fate and monitoring data, however, making this finding is challenging.
Many also believe that it is important that EPA demonstrate its ability to review new engineered nanoscale substances competently and consistent with its mandate under TSCA in order to preserve TSCA’s integrity. After all, TSCA’s core provisions pertinent in this regard were drafted almost 30 years ago, well before nanotechnology was known to allow the manipulation of matter at dimensions of one to 100 nanometers.
EPA’s abilities under TSCA are also under renewed scrutiny and TSCA is being compared to the European Union’s (EU's) new Registration, Evaluation, and Authorization of Chemicals (REACH) program, which many believe allows for a more thorough review of new chemicals as a condition of pre-market approval, and continued marketing in the case of existing chemicals. The contrast between TSCA and REACH will make it all the more important for EPA to demonstrate that its existing authorities are sufficient to achieve EPA’s overarching goal under the Voluntary Nanomaterials Program, namely that of providing the public with an assurance of safety with respect to these materials.