v>EPA

December 2022
EPA Document #740-S-22-006
United States	Office of Chemical Safety and

Environmental Protection Agency	Pollution Prevention

Non-Technical Summary of the Risk Evaluation for
n-Methylpyrrolidone (2-Pyrrolidinone, 1-Methyl-)

CASRN: 872-50-4

December 2022

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BACKGROUND

•	The TSCA risk evaluation for n-methylpyrrolidone (NMP) was issued in December 2020.

•	Uses for NMP include domestic manufacturing and import; processing as a reactant or
intermediate or into a formulation, mixture or reaction product; repackaging and recycling; a
variety of industrial and commercial uses including as a paint and coating additive and paint
and coating removers, a solvent in a variety of applications such as electrical equipment
manufacturing, a processing aid in a variety of applications including petrochemical
manufacturing, and for cleaning or degreasing. A variety of consumer and commercial
products use NMP in formulations including paints and coatings, paint and coating removers,
adhesives and sealants, and automotive and furniture cleaning products.

•	The total annual aggregate production volume reported under the Chemical Data Reporting
rule for the 2020 period indicates between 100 to 250 million pounds of NMP were
manufactured (including imported) in the United States.

ACTION

•	EPA is releasing a final revision to the risk determination on NMP with an order withdrawing
the TSCA section 6(i)(l) order previously included in the December 2020 risk evaluation. This
action follows issuance of a draft revised risk determination that EPA issued for comment in
July 2022 (87 FR 39511). EPA has determined that NMP presents an unreasonable risk of
injury to health under its conditions of use.

•	This final risk evaluation, which includes the 2020 risk evaluation and a 2022 final revised
unreasonable risk determination, is conducted pursuant to the Toxic Substances Control Act
(TSCA), as amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act,
which requires EPA to prioritize and evaluate the risk of existing chemicals to determine
whether a chemical presents an unreasonable risk of injury to health or the environment under
the conditions of use. Under TSCA, if a chemical is determined to present an unreasonable
risk, then EPA will propose risk management regulatory action to the extent necessary so that
the chemical substance no longer presents an unreasonable risk.

•	The 2020 risk evaluation, supplemental materials, 2022 revised unreasonable risk
determination and corresponding response to public comments can be found in dockets EPA-
HQ-OPPT-2019-0236 and EPA-HQ-OPPT-2016-0743 on www.regulations.gov.

•	NMP was selected in 2016 as one of the first 10 chemicals for risk evaluation under section 6
of TSCA.

KEY POINTS

•	EPA has identified risks for non-cancer adverse effects from acute and chronic inhalation and
dermal exposures to NMP. In the NMP risk characterization developmental effects were
identified as the best representative endpoint for non-cancer adverse effects from acute
inhalation and dermal exposures, and reproductive effects were identified as the best
representative endpoint for non-cancer adverse effects from chronic inhalation and dermal
exposures for all conditions of use.

•	Additional risks associated with other adverse effects (e.g., liver toxicity, kidney toxicity,
immunotoxicity, neurotoxicity, irritation and sensitization) were identified for acute and
chronic exposures.

•	Public comments and external scientific peer review informed the development of the NMP
final risk evaluation. EPA published the NMP final revised unreasonable risk determination in

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December 2022, the NMP draft revised unreasonable risk determination in July 2022, the NMP
risk evaluation in December 2020, the NMP draft risk evaluation in November 2019 (for a 60-
day public comment period), the NMP problem formulation document in June 2018, and the
scope document in June 2017.

•	Additionally, EPA held a peer review meeting of the Science Advisory Committee on
Chemicals (SACC) on the draft risk evaluation of NMP on December 5-6, 2019.

•	In the revised unreasonable risk determination for NMP, EPA is making an unreasonable risk
determination for NMP as a whole chemical substance, rather than taking a condition of use-
specific approach. The whole chemical approach is appropriate for NMP because there are
benchmark exceedances for a substantial number of conditions of use for human health and
there are irreversible health effects associated with NMP exposures.

•	After evaluating 37 conditions of use, EPA determined that NMP presents an unreasonable risk
to human health under its conditions of use based on risk of injury to health of workers during
occupational exposures and to consumers.

•	In addition, EPA is revising the assumption that workers always and properly use personal
protective equipment (PPE), although EPA does not question public comments received
regarding the occupational safety practices often followed by industry. Information on the use
of PPE as a means of mitigating risk will be considered during the risk management phase.
Removing the assumption that workers wear PPE means that three additional conditions of use
in addition to the original 26 drive the unreasonable risk for NMP, and for five conditions of
use, acute effects in addition to chronic effects also drive the unreasonable risk to workers.

•	Overall, 29 of the 37 conditions of use evaluated drive the NMP whole chemical unreasonable
risk determination due to risks identified for human health. These conditions of use include but
are not limited to: domestic manufacturing and import; processing as a reactant or intermediate
or into a formulation, mixture or reaction product; repackaging and recycling; a variety of
industrial and commercial uses including as a paint and coating additive and paint and coating
removers, a solvent in a variety of applications such as electrical equipment manufacturing, a
processing aid in a variety of applications including petrochemical manufacturing, and for
cleaning or degreasing. A variety of consumer and commercial products use NMP in
formulations including paints and coatings, paint and coating removers, adhesives and sealants,
and automotive and furniture cleaning products.

•	The conditions of use that do not drive EPA's unreasonable risk determination for NMP
include distribution in commerce; consumer use in paint and coating removers; adhesive
removers; lacquers, stains, varnishes, primers and floor finishes; paint and coating additives;
automotive care products; cleaning and furniture care products; and lubricant and lubricant
additives including hydrophilic coatings.

•	For NMP the exposure pathways that were or could be regulated under another EPA-
administered statute were not fully assessed as part of the final risk evaluation (see section
1.4.2 of the December 2020 NMP Risk Evaluation). For NMP, some exposure pathways
received only a screening-level analysis. During problem formulation, EPA conducted a first-
tier screening analysis for the ambient air pathway to near field populations downwind from
industrial and commercial facilities releasing NMP which indicated low risk. In the December
2020 NMP Risk Evaluation EPA conducted a first-tier analysis to estimate NMP surface water
concentrations and did not identify risks from incidental ingestion or dermal contact during
swimming. This resulted in the ambient air and drinking water pathways for NMP not being
fully assessed in the risk evaluation published in December 2020. EPA is conducting a

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screening approach to assess risks from the air and water pathways for several of the first 10
chemicals, including NMP. The goal of the recently-developed screening approach is to
remedy this exclusion and to determine if there are risks that were unaccounted for in the NMP
risk evaluation. EPA expects to describe its findings regarding the chemical-specific
application of this screening-level approach in the forthcoming proposed rule under TSCA
section 6(a) for NMP.

•	EPA did not identify risks of injury to the environment that drive the unreasonable risk
determination for NMP.

•	As noted above, EPA is releasing a final revision to the unreasonable risk determination with
an order withdrawing the TSCA section 6(i)(l) order previously included in the December
2020 risk evaluation. EPA is also releasing a document with response to public comments
received on the draft revised risk determination for NMP published in July 2022.

NEXT STEPS

•	EPA has issued the final risk evaluation (2020 risk evaluation and 2022 revised risk
determination) for NMP, meeting the requirements set forth in TSCA section 6(b) for chemical
risk evaluations. EPA is now initiating the process to address the unreasonable risk identified.
Following the issuance of the final risk evaluation, EPA will address, by rule, the unreasonable
risk identified. The public will have an opportunity to comment on a proposed rule before EPA
issues a final rule.

SUMMARY OF UNREASONABLE RISK DETERMINATION

EPA has determined that NMP presents an unreasonable risk of injury to human health under the
conditions of use.

EPA's unreasonable risk determination for NMP is driven by risks associated with the following
conditions of use, considered singularly or in combination with other exposures:

•	Manufacturing - Domestic manufacture;

•	Manufacturing - Import;

•	Processing as a reactant or intermediate in plastic material and resin manufacturing and
other non-incorporative processing;

•	Processing for incorporation into a formulation, mixture, or reaction product in multiple
sectors;

•	Processing for incorporation into articles—in lubricants and lubricant additives in
machinery manufacturing;

•	Processing for incorporation into articles in paint additives and coating additives not
described by other codes in transportation equipment manufacturing;

•	Processing for incorporation into articles as a solvent (which become part of product
formulation or mixture), including in textiles, apparel, and leather manufacturing;

•	Processing for incorporation into articles in other sectors, including in plastic product
manufacturing;

•	Processing in recycling;

•	Processing for repackaging (wholesale and retail trade);

•	Industrial and commercial use in paints, coatings, and adhesive removers;

•	Industrial and commercial use in paints and coatings in lacquers, stains, varnishes, primers,
and floor finishes, powder coatings (surface preparation);

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•	Industrial and commercial use in paint additives and coating additives not described by
other codes in computer and electronic product manufacturing in electronic parts
manufacturing;

•	Industrial and commercial use paint additives and coating additives not described by other
codes in computer and electronic product manufacturing in semiconductor manufacturing;

•	Industrial and commercial use paint additives and coating additives in multiple
manufacturing sectors;

•	Industrial and commercial use as a solvent (for cleaning or degreasing) in electrical
equipment, appliance and component manufacturing;

•	Industrial and commercial use as a solvent (for cleaning or degreasing) in electrical
equipment appliance and component manufacturing in semiconductor manufacturing;

•	Industrial and commercial use in processing aids specific to petroleum production in
petrochemical manufacturing, in other uses in oil and gas drilling, extraction, and support
activities, and in functional fluids (closed systems);

•	Industrial and commercial use in adhesives and sealants including binding agents, single
component glues and adhesives, including lubricant additives, two-component glues, and
adhesives including some resins;

•	Industrial and commercial use in other uses in anti-freeze and de-icing products,
automotive care products, and lubricants and greases;

•	Industrial and commercial use in metal products not covered elsewhere and lubricant and
lubricant additives including hydrophilic coatings;

•	Industrial and commercial uses in other uses in laboratory chemicals;

•	Industrial and commercial uses in other uses in lithium ion battery manufacturing;

•	Industrial and commercial uses in other uses in cleaning and furniture care products
including wood cleaners and gasket removers;

•	Industrial and commercial use in ink, toner, and colorant products (printer ink; inks in
writing equipment);

•	Industrial and commercial use in other uses in soldering materials;

•	Industrial and commercial use in other uses in fertilizer and other agricultural chemical
manufacturing in processing aids and solvents;

•	Consumer use in adhesives and sealants (glues and adhesives including lubricant
adhesives); and

•	Disposal.

The following conditions of use do not drive EPA's unreasonable risk determination for NMP:

•	Distribution in commerce;

•	Consumer use in paint and coating removers;

•	Consumer use in adhesive removers;

•	Consumer use in paints and coatings in lacquers, stains, varnishes, primers and floor
finishes;

•	Consumer use in paint additives and coating additives not described by other codes in
paints and arts and crafts paints;

•	Consumer use in other uses in automotive car products;

•	Consumer use in other uses in cleaning and furniture care products, including wood
cleaners and gasket removers; and

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• Consumer use in other uses in lubricant and lubricant additives, including hydrophilic
coatings.

EPA is not making condition of use-specific risk determinations for these conditions of use, is not
issuing a final order under TSCA section 6(i)(l) for these conditions of use, and does not consider
the revised risk determination for NMP to constitute a final agency action at this point in time.

Consistent with the statutory requirements of TSCA section 6(a), EPA will propose risk
management regulatory action to the extent necessary so that NMP no longer presents an
unreasonable risk. EPA expects to focus its risk management action on the conditions of use that
drive the unreasonable risk. However, it should be noted that, under TSCA section 6(a), EPA is not
limited to regulating the specific activities found to drive unreasonable risk and may select from
among a suite of risk management requirements in section 6(a) related to manufacture (including
import), processing, distribution in commerce, commercial use, and disposal as part of its
regulatory options to address the unreasonable risk. As a general example, EPA may regulate
upstream activities (e.g., processing, distribution in commerce) to address downstream activities
(e.g., consumer uses) driving unreasonable risk, even if the upstream activities do not drive the
unreasonable risk.

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