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February 26, 2013

EPA Proposes SNURs for 37 Chemical Substances, Including 14 Nanomaterials

The ACTA Group

On February 25, 2013, the U.S. Environmental Protection Agency (EPA) published proposed significant new use rules (SNUR) under the Toxic Substances Control Act (TSCA) for 37 chemical substances that were the subject of premanufacture notices (PMN). In addition, 17 of the chemical substances are subject to TSCA Section 5(e) consent orders issued by EPA. If issued in final, the SNURs would require persons who intend to manufacture, import, or process the chemical substances for an activity that is designated as a significant new use to notify EPA at least 90 days before commencing that activity. EPA states that the required notification would provide it with the opportunity to evaluate the intended use and, if necessary, to prohibit or limit that activity before it occurs. Comments are due April 26, 2013.

EPA notes that the proposed SNURs include 14 PMN substances whose reported chemical names include the term “carbon nanotube” (CNT) or “carbon nanofibers.” EPA states that, because of a lack of established nomenclature for CNTs, the TSCA Inventory names for CNTs are currently in generic form, e.g., CNT, multi-walled carbon nanotube (MWCNT), double-walled carbon nanotube (DWCNT), or single-walled carbon nanotube (SWCNT). According to the notice, EPA uses the specific structural characteristics provided by the PMN submitter to characterize more specifically the TSCA Inventory listing for an individual CNT. All submitters of new chemical notices for CNTs have claimed those specific structural characteristics as confidential business information (CBI). EPA states that it is publishing 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.

Because confidentiality claims preclude a more detailed description of the identity of these CNTs, EPA asks that an intended manufacturer, importer, or processor of CNTs that is unsure whether its CNTs are subject to the proposed SNUR contact EPA or obtain a written determination from EPA pursuant to the bona fide procedures at 40 C.F.R. Section 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.

Importantly, EPA has compiled a generic list of those structural characteristics entitled “Material Characterization of Carbon Nanotubes for Molecular Identity (MI) Determination & Nomenclature,” which will be available at under docket ID number EPA-HQ-OPPT-2012-0727. If EPA develops a more specific generic chemical name for these materials, that name will be made publicly available.

The proposed rule includes 17 PMN substances for which EPA determined, pursuant to TSCA Section 5(e), that uncontrolled manufacture, import, processing, distribution in commerce, use, and disposal may present an unreasonable risk of injury to human health or the environment. Accordingly, EPA states, these substances are subject to “risk-based” consent orders under TSCA Section 5(e)(1)(A)(ii)(I). These consent orders require protective measures to limit exposures or otherwise mitigate the potential unreasonable risk. EPA states that the “so-called ‘section 5(e) SNURs'” on these PMN substances are proposed pursuant to 40 C.F.R. Section 721.160, and are based on and consistent with the provisions in the underlying consent orders. The Section 5(e) SNURs designate as a “significant new use” the absence of the protective measures required in the corresponding consent orders.

According to the notice, where EPA determined that the PMN substance may present an unreasonable risk of injury to human health via inhalation exposure, the underlying TSCA Section 5(e) consent order usually requires that potentially exposed employees wear specified respirators unless actual measurements of the workplace air show that air-borne concentrations of the PMN substance are below a New Chemical Exposure Limit (NCEL) established by EPA. In addition to the actual NCEL concentration, EPA states that the comprehensive NCELs include requirements addressing performance criteria for sampling and analytical methods, periodic monitoring, respiratory protection, and recordkeeping. No comparable NCEL provisions currently exist for SNURs, however. For these cases, the individual SNURs typically state that persons subject to the SNUR who wish to use NCELs as an alternative to the 40 C.F.R. Section 721.63 respirator requirements may request to do so under Section 721.30. According to the notice, EPA expects that persons whose Section 721.30 requests to use the NCELs approach are approved will be required to comply with NCELs provisions comparable to those contained in the corresponding TSCA Section 5(e) consent order for the same chemical substance.

In addition, the notice includes proposed SNURs for 20 PMN substances that are not subject to TSCA Section 5(e) consent orders. EPA states that, in these cases, for a variety of reasons, it did not find that the use scenario described in the PMN triggered the determinations set forth under TSCA Section 5(e). EPA notes that it does believe that certain changes from the use scenario described in the PMN could result in increased exposures, however, thereby constituting a “significant new use.” EPA determined that every activity designated as a “significant new use” in all non-Section 5(e) SNURs issued under 40 C.F.R. Section 721.170 satisfies the two requirements stipulated in Section 721.170(c)(2), i.e., these significant new use activities “(i) are different from those described in the premanufacture notice for the substance, including any amendments, deletions, and additions of activities to the premanufacture notice, and (ii) may be accompanied by changes in exposure or release levels that are significant in relation to the health or environmental concerns identified” for the PMN substance.


Based on a review of past notices proposing SNURs since 2011, it appears that most if not all of those proposals involve substances whose PMNs were submitted in the same approximate timeframe (i.e., since 2010). Although EPA provides no explanation in the Federal Register notice as to why it is proposing the SNURs in the current rule at this time, it is interesting to note that about one-third of these substances had PMN review periods prior to 2010 with a number of them dating back more than ten years ago.

The 15 nanoparticle SNUR cases involving nanotubes or nanofibers (including the proposed SNUR concerning a “carbide derived nanocarbon,” which seems to represent a different form of carbon-based nanoparticle) have PMN submission years between 2008 and 2011, as follows:


* Carbide derived nanoparticle.

More pronounced lags between PMN submission and proposed SNUR can be seen in the non-nanoparticle SNURs that have PMN submissions dating back to the year 2000 up through 2012, as follows:


Based on these statistics, most of the proposed SNURs are from the recent past (P-10 through P-12), although 22 percent (8/37) come from fairly dated PMNs (submitted P-00 through P-04). The chemical classes for the non-nanoparticle substances are relatively diverse although 13 of the cases involve various types of isocyanate-based chemicals and polymers (the earliest was P-03), while three of the cases involve lithium metal phosphates used as electrodes (the earliest of these was P-02). Thus, while EPA is continuing to make progress in clearing out its older SNUR cases, evidently some number remain at play.

EPA may have anticipated that given the passage of time, comment might reasonably be expected from regulated entities, which is perhaps why the rule has been issued as a proposed rule instead of a direct final rule. Under some circumstances, SNUR requirements may no longer be needed or appropriate, again given the passage of time, and stakeholders interested in a particular PMN should review the proposal with this in mind. Or perhaps EPA did not give those long-ago notifiers the required notice of its intent to use the expedited SNUR procedure during the 90-day review period and is required to use notice and comment procedures (for more discussion on this point, see the September 12, 2011, BNA Daily Environment Report article on SNURs, available online, which discusses procedural aspects of the expedited SNUR). Regardless, in these instances, interested stakeholders should carefully consider if the proposed SNUR triggers for those chemicals are in fact “significant new uses” or, if these proposed significant new uses are currently on-going, whether a comment to that effect should be developed. Interestingly, because EPA has dispensed with the direct final rule approach as to these SNURs, issuance of a final rule may actually occur sooner than it would if EPA were to issue a direct final rule and received an intent to submit adverse comment on it. In that case, EPA would be required to withdraw that portion of the direct final rule and seek notice and comment on a newly issued proposed rule.

As noted, comment is due by April 26, 2013.