EPA’s TSCA Pre-Prioritization Webinar

On September 30, 2024, a lead toxicologist in the Data Gathering Management and Policy Division within the Office of Pollution Prevent and Toxics presented an overview of prioritization and pre-prioritization efforts for existing chemicals under the Toxic Substances Control Act (TSCA). The Agency’s goal was to collaborate with attendees to evaluate the potential risks of existing industrial chemicals regulated under TSCA. Topics covered included a high-level overview of TSCA authorities, requirements, and timelines for evaluating existing chemicals. Additionally, EPA covered the Agency’s approach for identifying the chemicals that may undergo prioritization.

Under TSCA, EPA is required to evaluate the potential risks of chemical substances comprehensively, taking into account their cradle-to-grave life cycle. This process involves assessing the chemical’s potential exposure and risks from production through disposal and includes all identified uses.  First, the webinar touched on the key aspects for the Risk Evaluation process.

  • Cradle-to-Grave Analysis
    • 6-Year Timeline for Risk Regulation
      • Initiation and Prioritization: 9-12 months.
      • Risk Evaluation: 3 to 3.5 years.
      • Regulation Development: Remainder of the timeline as needed.
  • Public Engagement and Information Gathering

 

EPA then noted that the prioritization process reflects the Agency’s evolving approach to addressing chemical risks efficiently and inclusively under TSCA. EPA identified 27 chemical substances that are being considered for prioritization under TSCA, focusing on their inclusion in the 2014 TSCA Work Plan, the interests of other agencies, and the availability of hazard and exposure data. The 2014 TSCA Work Plan identified approximately 90 chemicals as priorities for risk evaluation based on hazards, exposure risks, and their environmental or health impact. In addition, three chemical substances that were not listed in the 2014 Work plan are being considered for prioritization Two of these chemicals were identified through TSCA Section 21 petitions:  Hydrogen fluoride (HF) and 6PPD.  Bisphenol S (BPS) is also being considered for prioritization.  The Agency explained that BPS could become a priority if bisphenol A (BPA) undergoes prioritization, as BPS is a key alternative to BPA in the market.

EPA reminded participants that the Agency uses Section 4 and Section 8 under TSCA to gather data on the chemicals for prioritization, risk evaluation, and risk management. TSCA Section 4 provides authority for mandatory testing of chemicals to fill data gaps through test orders, test rules, and consent agreements. TSCA Section 8 allows for reporting and recordkeeping of existing chemical-related data, including reports of significant adverse health or environmental reactions.

The Agency noted that it prioritizes chemicals with robust existing data to streamline risk evaluation and reduce delays caused by insufficient information. The inclusion of both 2014 TSCA Work Plan chemicals and newly highlighted substances reflects intent to address historical priorities while also adapting to emerging concerns raised by stakeholders or other agencies.

Work Plan Chemicals:

1-Hexadecanol
2-Ethylhexyl
tetrabromobenzoate (TBB)
4-tert-Octylphenol (4-(1,1,3,3-Tetramethylbutyl)-phenol)
Benzene
bis(2-Ethylhexyl) – 3,4,5,6-Tetrabromophthalate (TBPH)
Bisphenol A
Creosote
Di-n-octyl phthalate (DnOP)
Ethylbenzene
Naphthalene
N-Nitroso-diphenylamine
p,p’-Oxybis(benzenesulfonylhydrazide)
Styrene
Tribromomethane
Triglycidyl isocyanurate
m-Xylene
o-Xylene
p-Xylene
Antimony & Antimony Compounds
Arsenic & Arsenic Compounds
Cobalt & Cobalt Compounds
Lead & Lead Compounds
Long-chain chlorinated paraffins (C18-20)
Medium-chain chlorinated paraffins (C14-17)

 

Non-Work Plan Chemicals:

Bisphenol S
Hydrogen fluoride
N-(1,3-Dimethylbutyl)-N’-phenyl-pphenylenediamine (6PPD)

DTSC Approves Preliminary Report on 6PPD Alternatives

This August, the California Department of Toxic Substances Control (DTSC) approved a revised stage 1 alternatives analysis report for 6PPD (CASRN 793-24-8) from the U.S. Tire Manufacturers Association (USTMA).  The preliminary report identified seven potential 6PPD alternatives for use in tires, which will be further assessed in the stage 2 alternatives analysis report due in August 2026.

6PPD, or N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine, has been used as an anti-degradant in tires since about the 1950s.  In 2020, it was discovered that 6PPD has a transformation product, 6PPD-quinone, that is extremely toxic to salmon and other aquatic species.  According to USTMA’s website, the organization “is not aware of any new motor vehicle tires available today that do not contain 6PPD.”

The seven potential 6PPD alternatives identified by the preliminary report are 7PPD, IPPD, 77PD, CCPD, specialized graphene, octyl gallate, and Irganox 1520, selected based on available information on potential hazards, performance, and chemical and physical properties indicative of exposure potential.  7PPD, IPPD, 77PD, and CCPD come from the same chemical family as 6PPD.  Eliminating the use of 6PPD without replacement is not an option, according to the preliminary report.

The stage 2 alternatives analysis will include a “more in-depth evaluation of hazard and exposure potential,” including additional evaluation of potential transformation products.  “At the end of [stage 2], we are optimistic that we will have identified one or more possible alternatives that hold promise to replace or materially reduce 6PPD in motor vehicle tires,” the preliminary report states.

The initial report was revised due to a notice of deficiency issued by DTSC, which was described by USTMA as “a standard step in the alternatives analysis process” that allows “regulators to provide suggestions and seek clarification about certain parts of a preliminary submission.”  Octyl gallate and Irganox 1520 were added to the list of potential alternatives in the revised report.

DTSC added 6PPD to the list of Priority Products under California’s Safer Consumer Products Program effective October 2023, prompting the alternatives analysis.  The following month, EPA granted a Toxic Substances Control Act citizen petition requesting that EPA take action to prohibit its use in tires.  EPA has since proposed a data call for substances including 6PPD-quinone, discussed in a previous blog post.

EPA Proposes Risk Management Rule for 1-Bromopropane

On August 8, 2024, EPA published a proposed rule to restrict use of the solvent 1-bromopropane (1-BP) (CASRN 106-94-5).  The proposed rule is the result of the agency’s revised 2022 determination that 1-BP presents an unreasonable risk of injury to human health due to effects including neurotoxicity, developmental toxicity, and carcinogenicity.

According to EPA, 1-BP is used in a wide variety of applications, including “vapor degreasing, aerosol degreasing, adhesives and sealants, and in insulation.”  Data from the Chemical Data Reporting rule shows that annual production of the substance, also known as n-propyl bromide, increased from 15.4 to 25.8 million pounds between 2012 and 2015.  This increase was because 1-BP is “an alternative to ozone-depleting substances and chlorinated solvents,” according to a 2020 EPA risk evaluation.

Under the proposed rule, all consumer uses of 1-BP would be banned except for use in insulation.  EPA is also proposing to prohibit four industrial and commercial uses, including use in adhesives and sealants, dry cleaning solvents, and automotive care products.  EPA estimates that these banned uses represent about 3% of the current annual production of 1-BP.

Other industrial and commercial uses would be subject to a workplace chemical protection program (WCPP), which would implement an inhalation exposure concentration limit for 1-BP of 0.05 ppm as an eight-hour time weighted average.  Use of chemically resistant gloves would also be required for uses including manufacturing, processing, and disposal.

Notably, in an effort to protect fenceline communities, EPA is proposing to prohibit owners or operators from increasing releases of 1-BP to outdoor air to comply with WCPP requirements.

EPA is proposing staggered compliance dates for the prohibited uses, which would become effective in six months for manufacturers, nine months for processors, and in 12 months for distribution to retailers.  Non-federal entities subject to the WCPP would be required to conduct baseline airborne exposure testing within six months and ensure that the inhalation exposure limit is met within nine months.

1-BP was added to the Toxics Release Inventory list of reportable chemicals in 2015 and became the first addition to the list of hazardous air pollutants in 2022.  More on 1-BP’s addition to the list can be found in a previous blog post.

Comments on the proposed rule are due September 23, 2024.

EPA Proposes to Designate Five Substances as High Priority

On July 25, 2024, EPA published a notice proposing to designate a new batch of existing chemicals as high priority substances under section 6 of the Toxic Substances Control Act (TSCA).  TSCA section 6 requires EPA to continually designate existing chemicals as “high-priority” based on factors including hazard and exposure potential.  Once a high priority designation is made, EPA is required to conduct a risk evaluation and regulate the chemical if it is found to present an unreasonable risk.

If the notice is finalized as proposed, EPA would immediately initiate risk evaluations for the following five substances:

  • Vinyl Chloride (CASRN 75-01-4)
  • Acetaldehyde (CASRN 75-07-0)
  • Acrylonitrile (CASRN 107-13-1)
  • Benzenamine (CASRN 62-53-3)
  • 4,4’-methylene bis(2-chloroaniline) (MBOCA) (CASRN 101-14-4)

According to an EPA press release, vinyl chloride is a known human carcinogen linked to liver, brain, and lung cancer in exposed workers.  In the release, EPA stated that vinyl chloride’s health hazards helped motivate the passage of TSCA in 1976.

The press release noted that the other four substances are probable human carcinogens and that some pose other types of hazards, such as respiratory and reproductive harms.  All five substances are used to make plastic; vinyl chloride is mostly used to make polyvinyl chloride, better known as PVC.

EPA announced that it was beginning the process of prioritizing these chemicals in December 2023.  In that announcement, EPA also stated that that it “expects to initiate prioritization on five chemicals every year, which will create a sustainable and effective pace for risk evaluations.”

Comments on the notice are due October 23, 2024.

EPA Proposes to Restrict Use of N-Methylpyrrolidone

Multiple occupational uses of n-methylpyrrolidone (NMP) would be banned and others would be restricted under a proposed rule published by EPA on June 14, 2024.  The proposed rule follows EPA’s 2020 determination that NMP presents an unreasonable risk to human health due to health effects including fetal death and reduced fertility.

According to the proposed rule, NMP is a widely used solvent with applications in the manufacturing of lithium-ion batteries, “semiconductors, polymers, petrochemical products, paints and coatings, and paint and coating removers.”  2020 Chemical Data Reporting rule data indicates that total annual production ranged from 100–250 million pounds from 2016 to 2019, EPA says.

The proposed rule would ban the manufacture, processing, distribution, and use of NMP for industrial and commercial use in lubricants, anti-freeze products, automotive care products, and cleaning products, among others.  All industrial and commercial uses not prohibited would be subject to a workplace chemical protection program (WCPP) to minimize direct dermal contact with NMP through incorporation of the hierarchy of controls.  Where controls are insufficient, EPA proposes to require implementation of a PPE program.

The proposed rule would also implement prescriptive controls for certain industrial and commercial uses, such as capping the allowed concentration of NMP in industrial and commercial paints and stains at 45%. Similar concentration maximums would apply to a handful of consumer products, including adhesives.

Although no consumer products would be banned, EPA proposes to implement container size limitations and labelling requirements for some consumer uses, including paint removers, paints, automotive care products, and cleaning products.

EPA proposes that the bans take effect under a staggered schedule, varying from one to two years after publication depending on whether an entity is a manufacturer, processor, distributor, or user of NMP.  Private entities subject to WCPP requirements would have one year to establish the program, and consumer product container size limitations and labelling requirements would also take effect after one year.

Comments on the proposed rule are due on July 29, 2024.

EPA Proposes to Request Unpublished Studies for 16 Chemicals

On March 26, 2024, EPA published a proposed rule that would require manufacturers of sixteen chemical substances to submit a wide breadth of unpublished studies to the Agency.

If finalized, the rule would amend the list of chemicals subject to health and safety reporting located at 40 CFR 716.120 by adding the following:

  • 4,4-Methylene bis(2-chloraniline) (CASRN 101–14–4)
  • 4-tert-octylphenol(4-(1,1,3,3- Tetramethylbutyl)-phenol) (CASRN140– 66–9)
  • Acetaldehyde (CASRN75–07–0)
  • Acrylonitrile (CASRN 107–13–1)
  • Benzenamine (CASRN 62–53–3)
  • Benzene (CASRN 71–43–2)
  • Bisphenol A (CASRN 80–05–7)
  • Ethylbenzene (CASRN 100–41–4)
  • Naphthalene (CASRN 91–20–3)
  • Vinyl Chloride (CASRN 75–01–4)
  • Styrene (CASRN 100–42–5)
  • Tribomomethane (Bromoform) (CASRN 75–25–2)
  • Triglycidyl isocyanurate; (CASRN 2451–62–9)
  • Hydrogen fluoride (CARN 7664– 39–3)
  • N-(1,3-Dimethylbutyl)-N′-phenyl-pphenylenediamine (6PPD) (CASRN 793– 24–8)
  • 2-anilino-5-[(4-methylpentan-2-yl) amino]cyclohexa-2,5-diene-1,4-dione (6PPD-quinone) (CASRN 2754428–18– 5).

EPA proposed to prioritize five of the listed chemicals (underlined above) for TSCA section 6 risk evaluation in December 2023.  The proposed rule also includes 10 chemicals EPA is considering including in its December 2024 initiation of prioritization.  The last substance, a 6PPD transformation product, was included as a result of EPA’s decision to grant a citizen’s petition on 6PPD.

Pursuant to 40 CFR 716.10 and 716.50, the requested information would include studies on health and safety, environmental effects, physical-chemical properties, exposure, and degradation.  Copies of unpublished studies, lists of known unpublished studies not in the submitter’s possession, and lists of ongoing studies would all be required.  Copies of each study previously listed as ongoing would also be required upon completion, regardless of the study’s completion date.

Studies previously submitted to EPA pursuant to a requirement under TSCA would be exempted from the request.  However, EPA proposes not to apply the typical exemption for persons manufacturing one of the 16 substances only as an impurity.

In addition to current manufacturers (including importers), persons who have manufactured or proposed to manufacture a listed substance within the past ten years would be required to submit the requested information.  Comments on the proposed rule are due on May 28, 2024.

EPA Proposes to Revise Rules for PBTs DecaDBE and PIP (3:1)

On November 24, 2023, EPA released a proposed rule to revise the final rules for decabromodiphenyl ether (“decaBDE”) and phenol, isopropylated phosphate (3:1) (“PIP (3:1)”), two persistent, bioaccumulative, and toxic substances (PBTs) subject to regulation under section 6 of the Toxic Substances Control Act (TSCA).

Section 6(h) of TSCA (as amended by the Lautenberg Amendments in 2016) required EPA to take expedited action to complete TSCA section 6(a) rules on certain PBTs.  In January 2021, EPA released final rules for decaBDE, PIP (3:1), and three other PBTs.  The final rules for decaBDE and PIP (3:1) generally prohibit their manufacture, processing, and use beginning in March 2021, though the rules contained phased-in prohibitions and exclusions for certain uses; EPA has extended certain phased-in prohibitions for PIP (3:1) multiple times since.

In light of new information and the Agency’s reinterpretation of the directive in TSCA section 6(h)(4) to “reduce exposures to the substance to the extent practicable,” EPA is proposing revisions to the final rules for decaBDE and PIP (3:1).  For decaBDE, the proposed revisions include:

  • Requiring a label on existing plastic shipping pallets containing decaBDE,
  • Requiring use of PPE for certain activities involving decaBDE,
  • Prohibiting releases to water during the manufacturing, processing, and commercial distribution of decaBDE and decaBDE-containing products,
  • Extending the current compliance extension for the processing and distribution in commerce of decaBDE-containing wire and cable insulation for use in nuclear power generation facilities, and
  • Requiring export notification for decaBDE-containing wire and cable for nuclear power generation facilities.

The proposed revisions to the PBT rule for PIP (3:1) include:

  • Narrowing the exclusion of prohibition for PIP (3:1) use in lubricants and greases to only include use in aerospace and turbine applications,
  • Replacing the exclusion from prohibition for motor and aerospace vehicle parts containing PIP (3:1) with phased-in prohibitions,
  • Excluding from prohibition the processing and commercial distribution of PIP (3:1) and PIP (3:1)-containing products for use in wire harnesses and circuit boards, and
  • Requiring PPE during manufacturing and processing of PIP (3:1).

In the proposed rule, EPA states that the Agency is not reconsidering the final rules for the other three PBTs–2,4,6-TTBP, HCBD, and PCTP–subject to final rules in January 2021.

According to EPA, decaBDE is a flame retardant that is used in textiles, plastics, adhesives, and polyurethane foam, and PIP (3:1) is a flame retardant, a plasticizer, and an anti-compressibility and anti-wear additive used in lubricants, hydraulic fluids, and in the manufacture of other compounds.

EPA Issues Draft Risk Evaluation for Flame Retardant TCEP

EPA has preliminarily determined that tris(2-chloroethyl) phosphate (TCEP) presents an unreasonable risk to human health and the environment, according to its draft risk assessment of the flame retardant released on December 14, 2023.  Animal testing data revealed that exposure to TCEP may increase risk of kidney cancer and other cancers, and could harm neurological and reproductive systems, the draft states.

According to EPA, domestic production of TCEP has decreased by about 99 percent since 2014.  However, the agency notes that TCEP is still used in paints, coatings, and in certain aerospace applications, and that previously-manufactured products containing TCEP—such as fabrics, certain types of foam, and construction materials—may still be in use.  The draft also states that “TCEP may still be found in a wide range” of imported goods.

Because TCEP is mixed into materials rather than being chemically bonded, it can leach out of products, EPA said.  Infant and child exposure from mouthing consumer products containing TCEP was determined to present an unreasonable risk.  The agency also found unreasonable risk of health effects for breastfed infants, people who handle TCEP at work, people who inhale TCEP dust off consumer products, and people who eat TCEP-contaminated fish.

EPA determined that TCEP presents an unreasonable risk to the environment due to studies on chronic exposures in fish and sediment-dwelling organisms.  The draft identified a number of ways by which TCEP can enter the environment, including manufacturing processes, air emissions, and leaching from products and landfills.  Although TCEP is not considered bioaccumulative, it is persistent in the environment, EPA said.

The draft risk evaluation is open for public comment and will undergo peer review by independent scientific and technical experts starting in March 2024.  If EPA still concludes that TCEP presents an unreasonable risk after public comment and peer review, the Toxic Substances Control Act requires the agency to take steps to mitigate its risks.

EPA Releases Draft Supplement for 1,4-Dioxane

In July 2023, EPA announced the release of a draft supplement to the Risk Evaluation for 1,4-dioxane for public comment and peer review.  1,4-dioxane is solvent used to manufacture other chemicals such as adhesives and sealants.  It is also used as a processing aid and laboratory chemical. In addition, some manufacturing processes, such as the process used for making commercial and consumer dish soaps, result in the chemical being present as a byproduct.

The draft supplement focuses on air and water exposure pathways that were not included in the 2020 Risk Evaluation.  The 2020 Risk Evaluation focused on health risks to workers, consumers, and the general public, but not from drinking water, the air, or exposure where 1,4-dioxane is present as a byproduct.  The omission was identified by the Scientific Advisory Committee on Chemicals (SACC) as an oversight.  The SACC informed EPA that failure to assess the risks posed to the general population from exposure to the chemical may present a risk to human health – with an emphasis on drinking water as an exposure pathway.

The draft supplement identified cancer risk estimates higher than 1 in 10,000 for 1,4-dioxane present as a byproduct and higher than 1 in 1 million for general population exposure scenarios associated with 1,4-dioxane in drinking water sourced downstream of release sites and in air within 1 km of releasing facilities.

The draft supplement did note that the risk estimates include inherent uncertainties and the overall confidence in specific risk estimates fluctuates.  However, the document also stated that the information is beneficial in helping the Agency make a determination on whether the chemical poses an unreasonable risk to people with occupational exposure, through sources of drinking water, and breathing air near release sites.

DuPont De Nemours Inc. Sues EPA Regarding GenX Test Order

Earlier this year, the US Court of Appeal for the Third Circuit ordered EPA to provide documentation regarding the Agency’s decision to order DuPont De Nemours Inc. to provide information on GenX chemicals through two section 4 test orders under the Toxic Substances Control Act (TSCA). DuPont brought this case to challenge the testing requirements imposed on the company, asserting that EPA had incorrectly identified the company as a manufacturer of the chemicals identified in the test orders:  hexafluoropropylene oxide (also known as trifluoro(trifluoromethyl)oxirane) and 6:2 Fluorotelomer sulfonamide betaine, two GenX chemicals. The test orders required testing on the inhalation effects toxicity of the chemicals in order to enable EPA to further understand protentional risks posed to human health and the environment. In addition to the cost of the toxicity studies, the manufacturers subject to the orders were assessed a fee of $11,650 to be split evenly amongst them.

After receiving the order to provide documentation, EPA requested several time extensions, but eventually stipulated to an agreement dismissing the case. The motion filed in May 2023 released DuPont from the test orders on 6:2 fluorotelomer sulfonamide betaine and hexafluoropropylene oxide. The Court then dismissed the case.