EPA Mandates Testing of "Forever Chemical" 6:2 Fluorotelomer Acrylate under National Testing Strategy

On October 9, 2024, the U.S. Environmental Protection Agency (EPA) issued its fifth Test Order under the Toxic Substances Control Act (TSCA) as part of its National PFAS Testing Strategy. This is the latest step in EPA’s PFAS Strategic Roadmap to address contamination from "forever chemicals". The order requires several companies to test 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl prop-2-enoate (CAS 17527-29-6), also known as 6:2 fluorotelomer acrylate or 6:2 FTAc. 6:2 FTAc, a chemical used in plastics, textiles, and other materials, with annual production ranging from 1 million to 20 million pounds.

Risk and Hazard Assessment Outcome

Summaries of studies on rodent exposure to 6:2 fluorotelomer acrylate (6:2 FTAc) indicate that it may alter blood cell counts, increase liver and kidney size, and affect animal behaviour. The chemical's structure raises concerns about its potential carcinogenic effects. PFAS, including 6:2 FTAc, can accumulate in the body and the environment, with even minimal exposure posing long-term health risks, including cancer, liver and heart damage, and developmental harm to infants and children.

EPA has determined that 6:2 FTAc may present an unreasonable risk to human health and the environment due to these hazards. The data gathered under this order will enhance the Agency’s understanding of the health effects of 6:2 FTAc and provide insights into the potential impacts of over a hundred structurally similar PFAS compounds. This information will also contribute to EPA's overall knowledge of this category of substances.

Recommendations in the Order

Companies affected by the Test Order may either perform the specified tests on physical-chemical properties and health effects from exposure or submit existing information that meets the order's requirements. EPA encourages collaborative testing to minimize duplication and will consider combining tests to address multiple endpoints, thus reducing time, costs, and reliance on animal subjects.

The order utilizes a tiered testing process, as mandated by TSCA. All but one of the first-tier test results must be submitted to EPA within one year of the order's effective date. Hydrolysis, as affected by pH, is a first-tier test that must be completed within 390 days. The outcomes of these initial tests will determine any additional testing requirements and methodologies.

Testing Required by the Order:

1. Physical-Chemical Properties

Tier 1.1- required testing

a. Melting point/ melting range (OECD 102 (1995))

b. Boiling point (OECD 103 (1995))

c. Vapor pressure (OECD 104 (2006)) as applicable to liquids

d. Water solubility (OECD 105 (1995))

e. Hydrolysis as a function of pH (OECD 111 (2004))

f. n-octanol/water Partition Coefficient HPLC Method, or KOW (OECD 117 (2022))

2. Environmental Fate and Behavior

Tier 1.1 – required testing

1. Estimation of the Adsorption Coefficient, or KOC, on Soil and Sewage Sludge using High

Performance Liquid Chromatography (HPLC) (OECD 121 (2001))

Tier 2.1 – required testing

1. Bioaccumulation in Fish: Aqueous and Dietary Exposure (OECD 305 (2012))

3. Health Effects: Dermal Route

Tier 1.2 – required testing dependent on results of Tier 1.1 Hydrolysis as a Function of pH test

a. Skin Absorption: In Vitro Method (OECD 428 (2004))

4. Health Effects: Mechanistic for Genotoxicity

Tier 1.2 – required testing dependent on results of Tier 1.1 Hydrolysis as a Function of pH; specific protocol may depend on results of the Tier 1.1 Vapor Pressure test

a. Bacterial Reverse Mutation Test (OECD 471 (2020))

b. One of the following:

i. In Vitro Mammalian Chromosomal Aberration Test (OECD 473 (2016))

ii. In Vitro Mammalian Cell Micronucleus Test (OECD 487 (2023))

iii. In Vitro Mammalian Cell Gene Mutation Tests Using the Thymidine Kinase Gene (OECD 490 (2016))

5. Health Effects: Oral and Inhalation Routes

Tier 2.1 – required testing

a. Toxicokinetics, oral exposure (OECD 417 (2010))

Tier 2.2 – required testing in a single rodent species dependent on TK oral study results

b. Toxicokinetics, inhalation exposure (OECD 417 (2010))

c. Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity

Screening Test (OECD 422 (2016))

The order and any data submitted in response will be publicly accessible on EPA’s website and in the relevant docket on Regulations.gov, with confidentiality provisions in accordance with TSCA Section 14.