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Assessing and Managing Chemicals under TSCA

Persistent, Bioaccumulative, and Toxic (PBT) Chemicals under TSCA Section 6(h)

As required under the Toxic Substances Control Act (TSCA), as amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act, EPA  issued five final rules on January 6, 2021 to reduce exposures to certain chemicals that are persistent, bioaccumulative and toxic (PBT). These chemicals build up in the environment over time and can therefore have potential risks for exposed populations, including the general population, consumers and commercial users, and susceptible subpopulations (such as workers, subsistence fishers, tribes and children).

In March 2021, EPA announced a 60-day public comment period to collect additional input on these final rules. Additionally, EPA issued a temporary 180-day “No Action Assurance” indicating that the agency will exercise its enforcement discretion regarding the prohibitions on processing and distribution of PIP (3:1) for use in articles, and the articles to which PIP (3:1) has been added in order to ensure that the supply chain of these important articles is not interrupted while EPA continues to collect the information needed to best inform subsequent regulatory efforts and allow for the issuance of a final agency action to extend the March 8, 2021, compliance date as necessary.

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Uses and Risk Management for Five PBT Chemicals under TSCA section 6(h)

The Frank R. Lautenberg Chemical Safety for the 21st Century Act, enacted on June 22, 2016, includes a provision under TSCA section 6(h) requiring EPA to take expedited action on specific PBT chemicals to address risk and reduce exposures to the extent practicable. EPA identified five PBT chemicals for expedited action in 2016, following criteria outlined in section 6(h) of TSCA and issued a proposed rule in 2019. EPA issued final rules on January 6, 2021. Pursuant to the statute, no risk evaluation was required for these chemicals.

Below is a summary of the uses, identified hazards, and risk management actions for each of the five PBT chemicals.

EPA is accepting additional public comments in docket EPA-HQ-OPPT-2021-0202 on www.regulations.gov for 60 days on these final rules.

Chemical  Uses and Identified Hazards Risk Management Actions
Decabromodiphenyl ether (DecaBDE)

DecaBDE is used as an additive flame retardant in plastic enclosures for televisions, computers, audio and video equipment, textiles and upholstered articles, wire and cables for communication and electronic equipment, and other applications. DecaBDE is also used as a flame retardant for multiple applications for aerospace and automotive vehicles, including replacement parts for aircraft and cars. Learn more about DecaBDE uses.


Identified Hazards – DecaBDE is toxic to aquatic
invertebrates, fish, and terrestrial invertebrates.
Data indicate the potential for developmental,
neurological, and immunological effects, general
developmental toxicity, liver effects, and carcinogenicity. While many uses of DecaBDE have ceased, EPA has concluded that humans or the environment are likely exposed to DecaBDE under the conditions of use identified in the final rule.

EPA is prohibiting the manufacture (including import), processing, and distribution in commerce of decaBDE, and products containing decaBDE, for all uses, except for the following:

  • Manufacture, processing, and distribution in commerce for use in curtains in the hospitality industry, and the distribution of the curtains themselves, for a period of 18 months, after which the prohibition would go into effect;
  • Processing and distribution in commerce for use in wire and cable insulation in nuclear power generation facilities, and the distribution of the wire and cable insulation that contains decaBDE, for a period of two years, after which the prohibition would go into effect;
  • Manufacture, processing, and distribution in commerce for use in parts for new aerospace vehicles, and distribution in commerce of the new vehicles containing such parts, for a period of three years, after which the prohibitions would go into effect;
  • Manufacture, processing, and distribution in commerce for those aerospace vehicles produced with decaBDE containing parts will be excluded from the prohibition until the end of their service lives; manufacture, processing, and distribution in commerce for use in replacement parts for aerospace vehicles, and distribution in commerce of the replacement parts themselves;
  • Manufacture, processing, and distribution in commerce for use in replacement parts in motor vehicles, and distribution in commerce of the replacement parts themselves until the end of the vehicles service lives or 2036, whichever is earlier;
  • Distribution in commerce of plastic shipping pallets manufactured prior to the publication of the final rule that contain decaBDE until the end of the pallets service lives; and
  • Processing and distribution in commerce for recycling of plastic that contained decaBDE before the plastic was recycled (i.e., the plastic to be recycled is from articles and products that were originally made with decaBDE), and the articles and products made from such recycled plastic so long as no new decaBDE is added during the recycling or production process.

Phenol, isopropylated phosphate (3:1)
(PIP (3:1))

PIP (3:1) is used as a plasticizer, a flame retardant, an anti-wear additive, or an anti-compressibility additive in hydraulic fluid, lubricating oils, lubricants and greases, various industrial coatings, adhesives, sealants, and plastic articles. As a chemical that can perform several functions simultaneously, sometimes under extreme conditions, it has several distinctive applications. Learn more about PIP (3:1) uses.

Identified Hazards – PIP (3:1) is toxic to aquatic plants, aquatic invertebrates, sediment invertebrates and fish. Data indicate the potential for reproductive and developmental effects, neurological effects and effects on systemic organs, specifically adrenals, liver, ovary, heart, and lungs.

EPA is prohibiting processing and distribution in commerce of PIP (3:1), and products containing the chemical substance, for all uses, except for the following:

  • Processing and distribution in commerce for use in aviation hydraulic fluid in hydraulic systems and use in specialty hydraulic fluids for military applications; 
  • Processing and distribution in commerce for use in lubricants and greases;
  • Processing and distribution in commerce for use in new and replacement parts for the aerospace and automotive industries;
  • Processing and distribution in commerce for use as an intermediate in the manufacture of cyanoacrylate glue;
  • Processing and distribution in commerce for use in specialized engine air filters for locomotive and marine applications;
  • Processing and distribution in commerce for use in sealants and adhesives; and
  • Processing and distribution in commerce for recycling of plastic that contained PIP (3:1) before the plastic was recycled (i.e., the plastic to be recycled is from articles and products that were originally made with PIP (3:1), and the articles and products made from such recycled plastic so long as no new PIP (3:1) is added during the recycling or production process.

 
EPA is requiring that persons manufacturing, processing, and distributing in commerce PIP (3:1) and products containing PIP (3:1) notify their customers of these restrictions.

EPA is also prohibiting releases to water from the remaining manufacturing, processing, and distribution in commerce activities, and requiring commercial users of PIP (3:1) and PIP (3:1)-containing products to follow existing regulations and best practices to prevent releases to water during use. 

2,4,6-Tris(tert-butyl)phenol (2,4,6-TTBP)

2,4,6-TTBP is used as an intermediate/reactant in processing and is incorporated into formulations destined for fuel and fuel-related additives, as well as into formulations intended for the maintenance or repair of motor vehicles and machinery, including in oils and lubricants. Learn more about 2,4,6-TTBP uses.

Identified Hazards – 2,4,6-TTBP is toxic to aquatic plants, aquatic invertebrates, and fish. Surveyed animal data indicate the potential for liver and developmental effects. The studies presented in this document demonstrate these hazardous endpoints. EPA has concluded that exposure to 2,4,6-TTBP under the conditions of use is likely.

EPA is prohibiting the distribution in commerce of 2,4,6-TTBP and products containing 2,4,6-TTBP at concentrations above 0.3% by weight in any container with a volume of less than 35 gallons in order to effectively prevent the use of 2,4,6-TTBP as a fuel additive or fuel injector cleaner by consumers and small commercial operations (e.g., automotive repair shops, marinas).

EPA is also prohibiting the processing and distribution in commerce of 2,4,6-TTBP, and products containing 2,4,6-TTBP, for use as an oil or lubricant additive in concentrations above 0.3% by weight regardless of container size.
Hexachlorobutadiene (HCBD) HCBD is used as a halogenated aliphatic hydrocarbon that
is produced as a byproduct during the manufacture of
chlorinated hydrocarbons, particularly perchloroethylene, trichloroethylene, and carbon tetrachloride and is subsequently burned as a waste fuel. Learn more about HCBD uses.

Identified Hazards – HCBD is toxic to aquatic invertebrates, fish, and birds, and has been identified as a possible human carcinogen. Data indicate the potential for renal, reproductive, and developmental effects.

EPA is prohibiting the manufacturing (including import), processing, and distribution in commerce of HCBD and HCBD-containing products or articles, except for the unintentional production of HCBD as a byproduct during the production of chlorinated solvents, and the processing and distribution in commerce of HCBD for burning as a waste fuel.

Pentachlorothiophenol (PCTP)

PCTP, which is also called PCTP, is used to make rubber more pliable in industrial uses. Learn more about PCTP uses.

Identified Hazards – PCTP is toxic to protozoa, fish, terrestrial plants, and birds. Data for analogous chemicals (pentachloronitrobenzene and hexachlorobenzene) indicate the potential for liver and reproductive effects. However, no animal or human hazard data has been identified.
EPA is prohibiting the manufacture (including import), processing, and distribution in commerce of PCTP, and products or articles containing PCTP, unless PCTP concentrations are at or below 1% by weight.

Additional Information

Letter Peer Reviews of Exposure and Hazard Information

EPA conducted letter peer reviews of exposure and hazard information for the five PBT chemicals. EPA also accepted written comments on the charge questions and other documents to be considered by the peer reviewers. These materials are available in docket EPA-HQ-OPPT-2018-0314.

Learn more about the letter peer reviews.

Webinar

On Thursday, September 7, 2017, at 2 pm EDT, EPA hosted a webinar, “Use Information for Persistent, Bioaccumulative, and Toxic (PBT) Chemicals Under TSCA Section 6(h).” This webinar provided background on the requirements for PBT chemicals under amended TSCA and explained to interested parties the process for gathering use and exposure information the five PBT chemicals.

Public Dockets

The public docket for all five final rules is EPA-HQ-OPPT-2019-0080.

Additionally, EPA previously established public dockets for each of the five PBT chemicals to facilitate receipt of information on exposure and use which may be useful to the agency’s rulemaking effort. To read the comments EPA received, visit the docket for each chemical.