EPA Extends Comment Period for Proposed SNURs

The U.S. Environmental Protection Agency (EPA) has announced that, in response to public comments, it will provide the public more time to comment on the December 28, 2011, proposed significant new use rules (SNUR) for 17 chemical substances that were the subject of premanufacture notices (PMN). Of particular interest, seven of the PMN substances’ reported chemical names include the term “carbon nanotube” (CNT) or “CNT.” EPA states “the comment period is being reopened until 45 days following publication of the new notice (until approximately mid-March).”  Importantly, the docket reveals that requests for extension were submitted by the International Center for Technology Assessment (ICTA), the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO), the United Automobile, Aerospace & Agricultural Implement Workers of America (UAW), and the United Steelworkers Union (USW).  The USW comment specifically asserts that the “specific protection measures required for individual PMN substances indicate that personal protective equipment, including gloves and respirators, should be the first line of defense to protect workers.  These requirements do NOT follow occupational health and safety best practices” (emphasis in original). The comment then goes on to cite the ANSI/AIHA Z10 2005 standard and the Occupational Safety and Health Administration (OSHA) standards as best practices.

This is an important perspective in the ongoing worker protection debate and the requests for comment deadline extension suggest that the unions are likely to become more engaged in this discussion.

 

EPA Publishes Proposed SNURs for CNTs

The U.S. Environmental Protection Agency (EPA) published on December 28, 2011, proposed significant new use rules (SNUR) for 17 chemical substances that were the subject of premanufacture notices (PMN). Of particular interest, seven of the PMN substances’ reported chemical names include the term “carbon nanotube” (CNT) or “CNT.”  EPA states that because of a lack of established nomenclature for CNTs, the Toxic Substances Control Act (TSCA) Inventory names for CNTs are currently in generic form, e.g., “carbon nanotube (CNT), multi-walled carbon nanotube (MWCNT), double-walled carbon nanotube (DWCNT), or single-walled carbon nanotube (SWCNT).” EPA uses the specific structural characteristics provided by the PMN submitter to characterize more specifically the TSCA Inventory listing for an individual CNT. According to EPA, all submitters of new chemical notices for CNTs have claimed those specific structural characteristics as confidential business information (CBI). The proposed rule includes the generic chemical name along with the PMN number to identify that a distinct chemical substance was the subject of the PMN without revealing the confidential chemical identity of the PMN substance. Comments are due January 27, 2012.

EPA notes that, since confidentiality claims preclude a more detailed description of the identity of the CNTs, if an intended manufacturer, importer, or processor of CNTs is unsure of whether its CNTs are subject to the proposed SNURs, the company can either contact EPA or obtain a written determination from EPA pursuant to the bona fide procedures at 40 C.F.R. § 721.11. EPA states that it is using the specific structural characteristics, for all CNTs submitted as new chemical substances under TSCA, to help develop standard nomenclature for placing these chemical substances on the TSCA Inventory. EPA has compiled a generic list of those structural characteristics entitled “Material Characterization of Carbon Nanotubes for Molecular Identity (MI) Determination & Nomenclature.”

Study Examines Cell Entry of One-Dimensional Nanomaterials

On September 18, 2011, Nature Nanotechnology posted an article entitled “Cell entry of one-dimensional nanomaterials occurs by tip recognition and rotation.” The authors state that materials with high aspect ratio, such as carbon nanotubes (CNT) and asbestos fibers, have been shown to cause length-dependent toxicity in certain cells because these long materials prevent complete ingestion, which frustrates the cell. The authors note that, while “[b]iophysical models have been proposed to explain how spheres and elliptical nanostructures enter cells,” one-dimensional nanomaterials have not been examined. The authors show “experimentally and theoretically” that cylindrical one-dimensional nanomaterials, such as CNTs, enter cells through the tip first. The abstract states:

For nanotubes with end caps or carbon shells at their tips, uptake involves tip recognition through receptor binding, rotation that is driven by asymmetric elastic strain at the tube-bilayer interface, and near-vertical entry.  The precise angle of entry is governed by the relative timescales for tube rotation and receptor diffusion.  Nanotubes without caps or shells on their tips show a different mode of membrane interaction, posing an interesting question as to whether modifying the tips of tubes may help avoid frustrated uptake by cells.

NIOSH Seeks Comment on Draft CIB Concerning Occupational Exposure to Carbon Nanotubes and Nanofibers

The National Institute for Occupational Safety and Health (NIOSH) released a draft Current Intelligence Bulletin (CIB) entitled Occupational Exposure to Carbon Nanotubes and Nanofibers, which recommends that, until results from research studies can fully elucidate the physicochemical properties of carbon nanotubes (CNT) and carbon nanofibers (CNF) that define their inhalation toxicity, employers should take steps to minimize CNT and CNF exposures of all workers and implement an occupational health surveillance program that includes elements of hazard and medical surveillance.  The draft CIB includes more specific recommendations for employers and workers to minimize potential health risks associated with exposure to CNTs and CNFs. NIOSH will hold a public meeting on the draft CIB on February 3, 2011, in Cincinnati, Ohio. According to NIOSH, during the meeting, it will place special emphasis on:

  • Whether the hazard identification, risk estimation, and discussion of health effects for CNTs and CNFs are a reasonable reflection of the current understanding of the evidence in the scientific literature;
  • Workplaces and occupations where exposure to CNTs and CNFs occur;
  • Current strategies for controlling occupational exposure to CNTs and CNFs (e.g., engineering controls, work practices, personal protective equipment);
  • Current exposure measurement methods and challenges in measuring workplace exposures to CNTs and CNFs; and
  • Areas for future collaborative efforts (e.g., research, communication, development of exposure measurement and control strategies).

Notification of intent to intend the meeting is due to NIOSH on January 28, 2011. Comments on the draft CIB are due February 18, 2011.

 

CDTSC and EPA Hold Public Workshop on State and Federal Nanomaterial Activities

On September 22, 2010, the California Department of Toxic Substances Control (CDTSC) and the U.S. Environmental Protection Agency (EPA) held a public workshop on state and federal nanomaterial activities. During the workshop, CDTSC and EPA discussed the results of California’s data call-in (DCI) for carbon nanotubes (CNT), its plans for future DCIs, and EPA’s efforts related to CNTs. The candidate chemicals for CDTSC’s second DCI, which it intends to issue this Fall, include nanosilver, nano zero valent iron, nano titanium dioxide, nano zinc oxide, nano cerium oxide, and quantum dots. CDTSC may also include in the DCI a request for more information concerning CNTs incorporated in nanometals. According to CDTSC, the DCI will focus its initial questions on analytical test methods for the respective nanomaterial chemical, as well as its metabolites and breakdown products, in various matrices. The meeting presentations for each of the DCI candidates include more specific information regarding applications, production, human health and environmental concerns, why CDTSC is interested, and possible DCI questions.

 

EPA Issues Final SNURs for Carbon Nanotubes

On September 17, 2010, the U.S. Environmental Protection Agency (EPA) issued final significant new use rules (SNUR) for two chemical substances that were the subject of premanufacture notices (PMN). The two chemical substances are identified generically as multi-walled carbon nanotubes (MWCNT) (PMN P08177) and single-walled carbon nanotubes (SWCNT) (PMN P08328). Persons who intend to manufacture, import, or process either of these substances for a use that is designated as a significant new use by the final rule must notify EPA at least 90 days before commencing that activity. EPA states that it believes the SNURs are necessary because these chemical substances may be hazardous to human health and the environment. The required notification would provide EPA with the opportunity to evaluate the intended use and, if necessary, to prohibit or limit that activity before it occurs. The final rule is effective October 18, 2010.

EPA issued direct final SNURs on these two substances on June 24, 2009. EPA withdrew the notices on August 21, 2009, after receiving notices of intent to submit adverse comments on the SNURs. EPA issued proposed SNURs on November 6, 2009. In response to comments on the applicability of the SNURs for these chemicals, EPA has included clarifying language for those forms of the subject PMN substances that are exempt from the provisions of the SNURs.  These exemptions apply to quantities of the PMN substances: after they have been completely reacted (cured); incorporated or embedded into a polymer matrix that itself has been reacted (cured); or embedded in a permanent solid polymer form that is not intended to undergo further processing except for mechanical processing. In response to comments on the basis for the SNURs, EPA developed revised human health effects and environmental effects summaries for carbon nanotubes (CNT).

CDTSC Reschedules Public Workshop on State and Federal Nanomaterial Activities

The California Department of Toxic Substances Control (CDTSC) has rescheduled its workshop on state and federal nanomaterial activities for September 22, 2010. CDTSC, the U.S. Environmental Protection Agency (EPA), and the University of California, Los Angeles (UCLA) are cosponsoring the workshop to discuss the results of California’s carbon nanotube (CNT) information call-in, future data call-in requests for additional nanomaterials, and federal efforts related to CNTs for nanomaterials. The workshop is open to the public.

CDTSC Postpones Public Workshop on State and Federal Nanomaterial Activities

Due to California’s budget issues and resulting furlough for civil service employees, the California Department of Toxic Substances Control (CDTSC) has postponed its August 13, 2010, workshop on state and federal nanomaterial activities. CDTSC, the U.S. Environmental Protection Agency (EPA), and the University of California, Los Angeles (UCLA) are cosponsoring the workshop to discuss the results of California’s carbon nanotube (CNT) information call-in, future data call-in requests for additional nanomaterials, and federal efforts related to CNTs for nanomaterials. CDTSC states that it will reschedule the workshop at a later date.

EPA Proposes a Second SNUR for Multi-Walled Carbon Nanotubes

The U.S. Environmental Protection Agency (EPA) published on February 3, 2010, a proposed significant new use rule (SNUR) under Section 5(a)(2) of the Toxic Substances Control Act (TSCA) for multi-walled carbon nanotubes. The proposed rule would require persons who intend to manufacture, import, or process the substance for an activity that is designated as a significant new use by the proposed rule to notify EPA at least 90 days before commencing that activity. EPA states that the required notification would provide EPA with the opportunity to evaluate the intended use and, if necessary, to prohibit or limit that activity before it occurs. Comments are due March 5, 2010.

The proposed rule provides the following basis for action:

The PMN states that the substance will be used as an additive/filler for polymer composites and support media for industrial catalysts. Based on test data on analogous respirable, poorly soluble particulates and on other carbon nanotubes (CNTs), EPA identified concerns for lung effects, immunotoxicity, and mutagenicity from exposure to the PMN substance. For the uses described in the PMN, worker inhalation and dermal exposures are minimal due to the use of adequate personal protective equipment. Therefore, EPA has not determined that the proposed manufacturing, processing, or use of the substance may present an unreasonable risk. EPA has determined, however, that use of the substance without the use of gloves and protective clothing, where there is a potential for dermal exposure; use of the substance without a National Institute for Occupational Safety and Health (NIOSH)-approved full-face respirator with an N100 cartridge, where there is a potential for inhalation exposure; or use other than as described in the PMN, may cause serious health effects. Based on this information, the PMN substance meets the concern criteria at 721.170(b)(3)(ii).

The proposed SNUR would apply only to the multi-walled carbon nanotubes described in premanufacture notice (PMN) P08-199. According to EPA, in the past, some stakeholders have asked whether these types of SNURs apply to all variants of carbon nanotubes. EPA states: “This is not the case.” The chemical name listed in the proposed SNUR is “multi-walled carbon nanotubes (generic),” and the CAS Number is “not available.” On November 6, 2009, EPA published a proposed SNUR for the multi-walled carbon nanotubes described in PMN P08-177.

EPA Extends Comment Period for Proposed CNT SNURs

On January 8, 2010, the U.S. Environmental Protection Agency (EPA) extended until February 8, 2010, the comment period for its November 6, 2009, proposed significant new use rules (SNUR) for multi-walled carbon nanotubes (CNT) and single-walled CNTs.  According to the January 8, 2010, notice, EPA received a request to extend the comment period.  On December 1, 2009, the U.S. World Trade Organization (WTO) Technical Barriers to Trade (TBT) Inquiry Point at the National Institute of Standards and Technology (NIST), on behalf of the European Economic Community (EEC) WTO TBT Enquiry Point, submitted a request to extend the comment period. According to the request, “the European Communities are currently reviewing the draft regulation,” and request that the comment deadline be extended. According to Charles Auer, formerly the Director of EPA’s Office of Pollution Prevention and Toxics (OPPT) and now affiliated with Bergeson & Campbell, P.C., this is the first request he is aware of from the EEC TBT Enquiry Point to OPPT. Auer noted that the EEC is not necessarily raising a trade concern, but may simply want to know the scope of the proposed regulation.

EPA Proposes SNURs for Carbon Nanotubes

On November 6, 2009, the U.S. Environmental Protection Agency (EPA) proposed significant new use rules (SNUR) under Section 5(a)(2) of the Toxic Substances Control Act (TSCA) for two chemical substances that were the subject of premanufacture notices (PMN). EPA identified the substances generically as multi-walled carbon nanotubes and single-walled carbon nanotubes. According to the notice, these substances are subject to TSCA Section 5(e) consent orders issued by EPA. The consent orders require protective measures to limit exposures or otherwise mitigate the potential unreasonable risk. The proposed SNURs are based on and consistent with the provisions in the underlying consent orders, and designate as a significant new use the absence of the protective measures required in the corresponding consent orders. Persons who intend to manufacture, import, or process either of these two substances for an activity that is designated as a significant new use would be required by the proposed rule to notify EPA at least 90 days before commencing that activity. The required notification would provide EPA with the opportunity to evaluate the intended use and, if necessary, to prohibit or limit that activity before it occurs. Comments are due December 7, 2009.

EPA Withdraws Final SNURs for CNTs

Today’s Federal Register includes a notice from the U.S. Environmental Protection Agency (EPA) withdrawing the June 24, 2009, final significant new use rules (SNUR) for multi- and single-walled carbon nanotubes (CNT). EPA states that it published the final SNURs using direct final rulemaking procedures. Because EPA received a notice of intent to submit adverse comments on the rules, it is withdrawing the SNURs for CNTs. The Federal Register notice does not identify the commenter. The docket for the rulemaking includes a July 22, 2009, letter from WilmerHale stating that it intends to submit adverse comments on behalf of one or more clients. According to the notice, EPA “intends to publish in the Federal Register, under separate notice and comment rulemaking procedures, proposed SNURS for these two chemical substances.” The withdrawal is effective August 21, 2009.

EPA Clarifies Final CNT SNURs

On July 28, 2009, the U.S. Environmental Protection Agency (EPA) clarified its June 24, 2009, final Significant New Use Rules (SNUR) for multi- and single-walled carbon nanotubes (CNT).  According to EPA, upon review of the final rule, stakeholders asked whether the SNURs applied to all types of CNTs.  EPA responded:

 

This is not the case.  These SNURs only apply to the specific carbon nanotubes that were the subject of the premanufacture notices (PMN) submitted under Section 5 of TSCA and not to any other carbon nanotubes.  Other carbon nanotubes must be notified through EPA's New Chemicals Program.  The U.S. EPA strongly encourages all manufacturers and importers of nanoscale materials that are intended for commercial use to consult with the Agency in advance of production or importation.

EPA Considering Test Rule For Multiwall CNTs

According to a notice in the U.S. Environmental Protection Agency's (EPA) May 11, 2009, Regulatory Agenda, a Toxic Substances Control Act (TSCA) Section 4(a) test rule “may be needed to determine the health effects” of multiwall carbon nanotubes (CNT). EPA states that the results of the tests that could be required under the rule could assist in understanding the health effects of the substance to manage/minimize any potential risk and exposure. Results could also help with establishing a correlation between the chemical/physical properties and health effects needed to protect the health of workers handling the substance. EPA has not determined when it will publish a notice of proposed rulemaking (NPRM).

NIOSH Requests Data on CNTs

On April 8, 2009, the National Institute for Occupational Safety and Health (NIOSH) published a Federal Register notice announcing that it “intends to evaluate the scientific data on carbon nanotubes (CNTs) and develop appropriate communication documents, such as an Alert and/or Current Intelligence Bulletin [CIB], which will convey the potential health risks and recommend measures for the safe handling of these materials.” CIBs are issued by NIOSH “to disseminate new scientific information about occupational hazards. A CIB may draw attention to a previously unrecognized hazard, report new data on a known hazard, or disseminate information on hazard control.”

According to the notice, NIOSH has developed guidelines for managing the potential health concerns associated with occupational exposures to engineered nanoparticles, which “will provide the framework for developing specific recommendations for CNTs.” Comments are due May 15, 2009.

NIOSH is requesting the following information:

  1. Published and unpublished reports and findings from in vitro and in vivo toxicity studies with CNTs;
  2. Information on possible health effects observed in workers exposed to CNTs;
  3. Information on workplaces and products in which CNTs can be found;
  4. Description of work tasks and scenarios with a potential for exposure;
  5. Workplace exposure data; and
  6. Information on control measures (e.g., engineering controls, work practices, personal protective equipment) that are being used in workplaces where potential exposures to CNTs occur.

HSE Publishes Information Sheet Regarding the Risk Management of CNTs

On March 6, 2009, the United Kingdom (UK) Health and Safety Executive (HSE) published an information sheet on the risk management of carbon nanotubes (CNT). According to HSE, the information sheet “is specifically about the manufacture and manipulation of carbon nanotubes and has been prepared in response to emerging evidence about the toxicology of these materials. However, the risk management principles detailed here are equally applicable to other nanodimensioned bio-persistent fibres with a similar aspect ratio.” HSE cites as “new evidence” a recent study by the University of Edinburgh, which “found that long, straight [multi-walled CNTs] with a high aspect ratio produced a marked inflammatory reaction and the formation of granulomas when injected into the abdominal cavity of mice.”

HSE states:

HSE views CNTs as being substances of very high concern. Although the recent findings only apply to some CNTs, we think a precautionary approach should be taken to the risk management of all CNTs, unless sound documented evidence is available on the hazards from breathing in CNTs. If their use cannot be avoided, HSE expects a high level of control to be used.

The information sheet includes specific recommendations for risk management. According to the information sheet, waste CNTs “should be classified and coded as hazardous waste.”

 

CDTSC Issues Data Call-In for Carbon Nanotubes

In a January 22, 2009, letter, the California Department of Toxic Substances Control (CDTSC) announced that it is requiring the submission of data “regarding analytical test methods, fate and transport in the environment, and other relevant information from manufacturers of carbon nanotubes” (CNT). CDTSC states that the term “manufacturers” includes persons and businesses that produce CNTs in California or import CNTs into California for sale.  According to the letter, CDTSC is using its authority under California Health and Safety Code, Chapter 699, Sections 57018-57020. Section 57019(d)(2) requires that the data requested be provided within one year of the date of the letter.

Researchers Review Environmental and Human Health Knowledge Base of Carbon Nanotubes

On May 10, 2007, EHP-in-Press posted an article entitled “Reviewing the Environmental and Human Health Knowledge Base of Carbon Nanotubes.” The authors reviewed the currently available literature about the human health and environmental risk potential of carbon nanotubes (CNT). The authors also investigated the life cycle of the CNT, as release into different environmental compartments may occur at the production stages as well as the product’s usage and disposal stages, which may indirectly or directly cause human exposure. Because, according to the authors, the published literature revealed many open questions, they also systematically interviewed seven leading scientists worldwide and integrated their contemporary knowledge in the review. The authors interviewed scientists who were key authors or project leaders, having investigated and reported the potential impacts of CNT on human health or environment. Through this combined approach, the authors present an updated and contemporary knowledge base for scientific discussion.