Fluorotelomer

Types

There are many broad categories of fluorotelomers:

• Fluorotelomer alcohols (FTOH)
• Fluorotelomer ethoxylates (FTEO)
• Fluorotelomer fumarates
• Fluorotelomer methacrylates (FTMAC)
• Fluorotelomer sulphonates (FTS)

Production

In the radical telomerization of fluorotelomer molecules, a variety of fluorinated alkenes can serve as unsaturated taxogens including tetrafluoroethylene, vinylidene fluoride, chlorotrifluoroethylene, and hexafluoropropene. However, many fluorotelomers, such as fluorotelomer alcohols, are fluorocarbon-based because they are synthesized from tetrafluoroethylene. In addition to alcohols, synthetic products include fluorotelomer iodides, olefins, and acrylate monomer.{{cite journal

Applications

Fluorotelomers are used in fire-fighting foams, grease-resistant food packaging, leather protectants and stain-resistant carpeting, textiles, anti-fogging sprays and wipes.{{cite news

Environmental and health concerns

Fluorotelomers that contain PFOA precursors can be metabolized into, and degrade to, PFOA, a persistent global contaminant found in people in the low-parts per billion range.{{cite journal

PFOA is also formed as an unintended byproduct in the production of fluorotelomers,{{cite web |url=http://www2.dupont.com/PFOA/en_US/ |title=Information on PFOA |publisher=DuPont |access-date=14 February 2009 |archive-date=24 May 2009 |archive-url=https://web.archive.org/web/20090524053639/http://www2.dupont.com/PFOA/en_US/ |url-status=dead}} and is thus present in finished goods treated with fluorotelomers, including those intended for food contact. In a U.S. Food and Drug Administration (USFDA) study, fluorotelomer-based paper coatings (which can be applied to food contact paper in the concentration range of 0.4%) were found to contain 88,000–160,000 parts per billion PFOA, while microwave popcorn bags contained 6–290 parts per billion PFOA.

Industry and government actions

In 2002 Burger King stopped using fluorotelomer coated boxes.

After more than a year of negotiating with "telomer makers Asahi Glass, Clariant, Daikin America, and DuPont to perform degradation studies on 13 of their products", the U.S. Environmental Protection Agency (USEPA) and companies were not able to agree on terms.{{cite journal |url-access=subscription}} Thus, in late June 2004 the USEPA announced it would perform the degradation studies itself, with an expected time to complete the studies of 1 year. Yet, in late December 2008, the USEPA and DuPont filed a joint motion stating that DuPont needed additional time to purify the products. USEPA lawyers extended the deadline by three years, to 27 December 2011, in the last month of the Bush administration.

In 2009 a 546-day USEPA study was published that estimated a degradation half-life for a fluorotelomer-based polymer in the range of 10–17 years.{{cite journal |doi-access=free}} Given this discrepancy, the USEPA undertook an extensive effort to develop methods for testing the degradation rate of commercial fluorotelomer-based polymers.{{cite journal

References

References

1. (5 January 2022). "High levels of toxic 'forever chemicals' found in anti-fogging sprays and wipes". The Guardian.
2. "Analysis of the unknown pool of PFAS: Total Oxidizable Precursors (TOP), PFOS Precursor (PreFOS) and Telomer Degradation". Eurofins.
3. (5 January 2022). "Characterization of Per- and Polyfluorinated Alkyl Substances Present in Commercial Anti-fog Products and Their In Vitro Adipogenic Activity". Environmental Science & Technology.
4. (2022). "Synthesis Report on Understanding Side-Chain Fluorinated Polymers and Their Life Cycle". OECD.
5. (2015). "Decades-Scale Degradation of Commercial, Side-Chain, Fluorotelomer-based Polymers in Soils & Water". Environ. Sci. Technol..
6. (2015). "Abiotic hydrolysis of fluorotelomer polymers as a source of perfluorocarboxylates at the global scale". Environ. Sci. Technol..
7. Sanford Lewis. [http://www.dupontshareholdersalert.org/DuPont_Shareholder_PDF/DSFV%202007%20Shareholders%20Report.pdf "The Shareholder’s Right To Know More - 2007 Update: DuPont’s Market and Liability Exposures Continue from PFOA and Related Issues"]{{Dead link. (November 2022)
8. Ward, Jr., Ken. (7 February 2009). "Bush EPA gave DuPont more time on key PFOA tests". The Charleston Gazette.