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Reviewing New Chemicals under the Toxic Substances Control Act (TSCA)

Actions under TSCA Section 5

After EPA reviews a pre-manufacture notice (PMN), a Microbial Commercial Activity Notice (MCAN) or Significant New Use Notice (SNUN) and makes a determination under section 5 of the Toxic Substances Control Act (TSCA), EPA may take certain actions.


New Chemicals Working Approach to Determinations Under TSCA Section 5

In December 2019, EPA updated its Working Approach for making new chemicals determinations under section 5 of TSCA. The updated document was discussed at a public meeting on December 10, 2019 and will be available for public comment for 45 days upon publication in the Federal Register in docket number EPA-HQ-OPPT-2019-0684. EPA previously published a version in 2017 and took comment.

Comments are due on or before February 18, 2020.

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TSCA section 5(a)(3)(C) “Not likely to present an unreasonable risk” determinations

In cases where EPA determines that a new chemical or significant new use is not likely to present an unreasonable risk of injury to health or the environment, without consideration of costs or other nonrisk factors, including an unreasonable risk to a potentially exposed or susceptible subpopulation under the conditions of use, EPA will notify the submitter of its decision under TSCA section 5(a)(3)(C) and publish its findings in a statement in the Federal Register pursuant to TSCA section 5(g).

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Significant New Use Rules (SNURs)

SNURs for Existing Chemicals (i.e., SNURs not promulgated as a result of TSCA New Chemicals Program review)

TSCA Section 5(a) Significant New Use Rules (SNURs) can be used to require notice to EPA before chemical substances and mixtures are used in new ways that might create concerns.

Under section 5(a) EPA can determine that a use of a chemical substance is a “significant new use.” EPA must make this determination by rule after considering all relevant factors, including those listed in TSCA section 5(a)(2):

  • Projected volume of manufacturing and processing of a chemical substance.
  • Extent to which a use changes the type or form of exposure of humans or the environment to a chemical substance.
  • Extent to which a use increases the magnitude and duration of exposure of humans or the environment to a chemical substance.
  • Reasonably anticipated manner and methods of manufacturing, processing, distribution in commerce, and disposal of a chemical substance.

Once EPA determines that a use of a chemical substance is a significant new use, TSCA section 5(a) requires persons to submit a significant new use notice (SNUN) to EPA at least 90 days before they manufacture (including import), or process the chemical substance for that use. The notification required by SNURs, known as a Significant New Use Notice (SNUN), obligates EPA to assess risks that may be associated with the significant new use, including risks to potentially exposed or susceptible subpopulations identified as relevant by EPA under the conditions of use; make a determination under the statute; and, if appropriate,  regulate the proposed activity before it occurs.

Learn about how to submit a Significant New Use Notice (SNUN).

Use of SNURs in the TSCA New Chemicals Program

EPA also issues SNURs associated with the Agency's review of a notice received under TSCA section 5.   EPA utilizes SNURs in the new chemicals program in three ways:

SNURs Preceding “Not Likely” Determinations. Promulgation of a significant new use rule (SNUR) can be an effective and efficient way to address reasonably foreseen conditions of use about which EPA has concerns, as part of the basis for EPA to conclude that the chemical is not likely to present an unreasonable risk of injury to health and the environment under the conditions of use under section 5(a)(3)(C).  A SNUR requires any manufacturer or processor – including the PMN submitter – who intends to undertake the activities subject to the SNUR  to submit to EPA a significant new use notice (SNUN). EPA must either conclude, following review of a SNUN, that the activities are not likely to present an unreasonable risk, or take appropriate action under section 5(e) or 5(f) to protect against any unreasonable risk. The review would factor in the conditions of use of the chemical specifically associated with the significant new use and, as appropriate, any other conditions of use relevant to the evaluation of the significant new use under section 5(a)(3).  The ability to issue a SNUR during the review period enables EPA to focus its technical analysis on the intended conditions of use of a chemical and defer further analysis of reasonably foreseen conditions of use until such time as the submitter (or any other entity) actually intends to undertake them.  This is consistent with EPA’s long-standing use of SNURs to defer detailed analysis of activities associated with chemicals until such time as someone indicates the intention to undertake the activities by submitting a SNUN.  See, e.g., 80 Fed. Reg. 2071 (January 15, 2015). 

It can be more efficient for EPA to address concerns associated with reasonably foreseen conditions of use by issuing a SNUR that applies to all parties, including the submitter, rather than by issuing an order to the submitter addressing activities the submitter does not intend to undertake, and then taking an additional regulatory action to issue a SNUR.

SNURs following TSCA section 5(e) or 5(f) Orders. TSCA section 5(e) or 5(f) Orders are only binding on the original PMN submitter for that substance. Consequently, after issuing a section 5 Order, EPA generally promulgates a SNUR that requires notice to EPA by any manufacturer or processor who wishes to manufacture or process the chemical in a way other than described in the terms and conditions contained in the Order. TSCA section 5(f)(4) requires EPA to either initiate a SNUR rulemaking or explain its reasons for not doing so following action under section 5(e) or 5(f). As described above, a SNUR requires that manufacturers (including importers) or processors notify EPA at least 90 days before beginning any activity that EPA has designated as a "significant new use." These new use designations are typically those activities prohibited by the section 5 Order. The required notification initiates EPA’s evaluation of the conditions of use associated with the chemical substance within the applicable review period. The review of the SNUN would be the same as described above.

SNURs following “Not Likely” Determinations. If EPA has determined that the chemical substance under its conditions of use is “not likely to present an unreasonable risk,” EPA may still issue a SNUR that follows the determination. Specifically, where EPA has identified other circumstances that – should they occur in the future, even if not reasonably foreseen – may present risk concerns, EPA may consider identifying those other circumstances as significant new uses. This ensures that those circumstances will not occur absent notification to the Agency and further review before manufacture or processing for the significant new use is commenced.  EPA has a long history of identifying such circumstances as significant new uses in a SNUR.

View all SNURs in ChemView by checking the SNUR box under EPA Actions in the Show Output Selection area of ChemView.

Proposed Changes to General Provisions for SNURs

EPA is proposing changes to the existing regulations governing significant new uses of chemical substances under TSCA to update and align these regulations with revisions to the Occupational Safety and Health Administration’s Hazard Communications Standard , the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals and with changes to the OSHA Respiratory Protection Standard and the National Institute for Occupational Safety and Health respirator certification requirements pertaining to respiratory protection of workers from exposure to chemicals. EPA is also proposing changes to other general significant new use regulations. Based on a request to extend the comment period, EPA reopened the comment period on October 21, 2016. Comments were due by November 21, 2016. Read the proposal.

EPA’s efforts to coordinate its SNUR program with Canada

EPA and Environment and Climate Change Canada/Health Canada (ECCC/HC) have been working together under the Regulatory Cooperation Council (RCC) to conduct a comparison of the new chemicals review programs in both nations, specifically EPA’s SNUR and Canada’s Significant New Activity (SNAc) programs that require notice to the governments before chemical substances and mixtures are used in new ways that might create environmental or health concerns. EPA and Canada convened stakeholders throughout the supply chain and facilitated two roundtable discussions to identify opportunities for regulators and stakeholders to increase regulatory transparency and coordination between the two countries. Read the summary report of the SNUR/SNAc RCC roundtable meetings, which identifies ways in which government and industry can work to better educate and inform stakeholders throughout the supply chain on their compliance requirements.

In April 2018, the RCC released an educational primer developed by the two governments on U.S. and Canadian regulations of chemical substances. Download in English or French.

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Is My Chemical Subject to a SNUR?

To facilitate determining whether a substance is subject to a SNUR, substances on the TSCA Inventory that are subject to SNUR requirements are designated as such by an "S" flag in the Inventory listing. If your chemical substance is subject to a SNUR and your intended manufacture, processing, or use of the substance is a significant new use, you would be required to submit a SNUN 90 days prior to the manufacture of that substance.

Several steps should be followed to ascertain the TSCA Inventory/SNUR status of a chemical substance. Information on non-confidential chemical substances can be found in the TSCA Chemical Substance Inventory. Because the chemical identities of the chemical substances can be claimed to be Confidential Business Information (CBI) by the submitters of PMNs, EPA maintains a CBI version of the TSCA Inventory. If an intended manufacturer submits a PMN or a Notice of Bona Fide Intent to Manufacture (pursuant to the procedures at 40 CFR Section 720.25 or 721.11) on a substance that has a listing on the Confidential Inventory, the Agency will notify the submitter of the existence of the SNUR.

Access the TSCA Chemical Substance Inventory and learn about submitting a Notice of Bona Fide Intent to Manufacture.

It is always the obligation of the manufacturer or processor selling a chemical substance to notify the user of the SNUR status of that substance. Buyers of a chemical substance whose identity is confidential, and thus not disclosed to them, should seek certification from the sellers that their intended use is not a significant new use.

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TSCA section 5 (e) Orders

One outcome of EPA's review of a PMN or MCAN for a new chemical substance or review of a SNUN for a significant new use is the issuance of an order under section 5(e) of TSCA. Most TSCA section 5(e) Orders issued by EPA are Consent Orders that are negotiated with the submitter of the notification. The Agency can determine that:

  • the information in the notice is insufficient to allow the Agency to make a reasoned evaluation of the health and environmental effects of the new chemical substance or the significant new use, or
  • in the absence of sufficient information, the manufacture, processing, distribution in commerce, use or disposal of the chemical may present an unreasonable risk to health or the environment, without consideration of costs or other non-risk factors, including an unreasonable risk to a potentially exposed subpopulation identified as relevant to the Administrator under the conditions of use, or
  • the chemical substance is or will be produced in substantial quantities and will either enter the environment in substantial quantities or there may be significant or substantial human exposure to the substance.

Where EPA makes one of these determinations, EPA must issue an order under TSCA section 5(e). These orders are typically issued on consent. A section 5(e) order typically contains some or all of the following requirements as conditions:

  • Testing for toxicity or environmental fate once a certain production volume or time period is reached
  • Use of worker personal protective equipment
  • New Chemical Exposure Limits (NCELs) for worker protection
  • Hazard communication language
  • Distribution and use restrictions
  • Restrictions on releases to water, air and/or land, and
  • Recordkeeping.

Consent Orders generally follow the relatively standard format used in the "boilerplate".

Consent Orders with NCELs provisions will include the NCELs section Order insert.

A company subject to a TSCA section 5(e) Order that requires testing to be conducted must notify, in writing, the EPA Monitoring Assistance and Media Programs Division (2227A), Office of Enforcement and Compliance Assurance (OECA), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, N.W., Washington D.C. 20460, of certain study-related information within 10 days of scheduling any study required to be performed pursuant to the Order.

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Coordination with other federal agencies

In January 2021, EPA and the Occupational Safety and Health  Administration (OSHA) announced a Memorandum of Understanding (MOU) that advances collaboration and communication on EPA’s review of new chemicals under the Toxic Substances Control Act (TSCA). This MOU provides a framework for coordination and communication between the two agencies on exposure to new chemicals in the workplace and will help achieve a common goal of ensuring workers are protected from potential risks.

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Reducing vertebrate testing where practicable

EPA has modified language in its regulatory documents to ensure consistency with TSCA section 4(h) requirements to reduce testing on vertebrates to the extent practicable. Section 5(e) Consent Orders will now contain a statement of need that explains the basis for any decision that requires the use of vertebrate animals. In addition, EPA is modifying language in its legal documents describing test requirements to reflect a preference for tiered testing and use of non-vertebrate testing strategies first and using that test data to inform whether higher tiered testing (including testing of vertebrates) is necessary.

Similarly, EPA is modifying language in its SNURs to more generally describe the information EPA believes would help characterize chemical properties, fate and/or the potential human health and environmental effects associated with a significant new use of the chemical substance, rather than list specific recommended tests. EPA is encouraging companies to consult with the Agency on the potential for use of alternative test methods and strategies (also called New Approach Methodologies, or NAMs) to generate data to inform risk assessment. EPA encourages dialogue with Agency representatives to help determine how best the submitter can meet both the data needs and the objective of TSCA section 4(h).

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Section 5(f) Actions: Protection Against Unreasonable Risk

If EPA determines that a new chemical or significant new use presents unreasonable risk of injury to health or the environment without consideration of cost or other nonrisk factors, including an unreasonable risk to a potentially exposed subpopulation under the conditions of use, EPA may (1) limit the amount manufactured/processed/distributed in commerce or impose other restrictions on the substance via an immediately effective proposed rule under section 6 of TSCA, or (2) issue an order to prohibit or limit the manufacture, processing or distribution in commerce to take effect on the expiration of the applicable review period.

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