More than a decade after 3M stopped production of PFOS-based AFFF agents; there is continued discussion within the fire protection industry on the environmental impact and efficacy of fire fighting
foams. The discussion of environmental impact is usually focused on foams that contain fluorochemicals, while the discussion of efficacy is usually focused on foams that do not contain fluorochemicals.
Key facts
All modern AFFF agents (except some produced in China) contain telomer-based fluorosurfactants.
Telomer-based AFFF agents are the most effective foams currently available to fight flammable liquid fires in military, industrial, aviation, and municipal applications. They provide rapid
extinguishment, burnback resistance, and protection against vapour release.
Fire test results presented at the 2011 SUPDET conference and 2013 Reebok conference showed that AFFF agents are significantly more effective at extinguishing flammable liquid fires than
fluorine-free foams.
Telomer-based foams do not contain or break down into PFOS (per fluorooctane sulfonate) or homologues of PFOS such as PFHxS (perfluorohexane sulfonate).
Telomer-based foams do not contain or break down into any chemicals that are currently listed as persistent organic pollutants (POPs) under the Stockholm Convention.
Telomer-based foams are not made with PFOA (perfluorooctanoic acid) or any PFOA-based products.
Telomer-based foams are not made with any chemicals that are currently considered by environmental authorities to be persistent, bioaccumulative, and toxic (PBT).
Telomer-based foams are not banned or restricted from use. We are aware of no pendinglegislation to regulate telomer-based foams in Australia, Canada, Europe, Japan, or the United States.
The C6-based fluorosurfactants that have been the predominant fluorochemicals used in telomer based AFFF for the last 25 years are low in toxicity and not considered to be bioaccumulative or
biopersistent.
Foam manufacturers are in the process of transitioning to the use of pure C6-based fluorosurfactants in response to the US EPA PFOA stewardship program.
Fluorinated Surfactants
All AFFF firefighting agents contain fluorinated surfactants (fluorosurfactants). They are key ingredients that provide AFFF with the required low surface tension (15 to 17 mN/m) and positive
spreading coefficient that enables film formation on top of lighter fuels. It is this film formation capability that gives AFFF its name and its effectiveness against flammable liquid fires. The chemicals
used to produce fluorosurfactants can be manufactured by different processes and have different chemical structures. The fluorosurfactants used in AFFF have historically been produced from
fluorochemicals manufactured by two methods: electrochemical fluorination and telomerization. AFFF agents manufactured by 3M contain fluorosurfactants produced by electrochemical fluorination. All other AFFF agents contain fluorosurfactants produced by telomerization.
PFOS
In 2002, 3M voluntarily stopped production of a number of products including AFFF agents because they contain and degrade into perfluorooctane sulfonate (PFOS). PFOS is considered by environmental authorities to be persistent, bioaccumulative and toxic (PBT). Regulations in the United States, Canada, European Union, Australia, and Japan act as a ban on new production of PFOS-based products including foams. These regulations do not currently restrict the use of existing stocks of PFOS-based foam in the US, Australia, or Japan. In the EU and Canada, existing stocks of PFOS-based foam must be removed from service in 2011 and 2013, respectively. Production and sale of PFOS foams continues in China.
Telomers
All modern AFFF agents (except some produced in China) contain telomer-based fluorosurfactants. Telomer-based AFFF agents do not contain or break down into PFOS and have about 30 - 60% less
fluorine than PFOS-based AFFF. Telomer-based AFFF agents are not made with any chemicals that are currently considered by environmental authorities to be PBT. The US Environmental Protection Agency (EPA) has indicated that some telomer-based fluorochemicals can break down in the environment into perfluorooctanoic acid (PFOA) or other perfluorocarboxylic acids (PFCAs). Further, EPA states that their concern is focused on long-chain perfluorinated chemicals (LCPFCs) containing eight carbons or more (C8, C10, C12). Existing data shows that shorter-chain compounds (C6 and below) have a lower potential for toxicity and bioaccumulation.
EPA PFOA Stewardship Program
Under the EPA 2010/15 PFOA Stewardship Program eight fluorochemical manufacturers have voluntarily agreed to reduce by 95% by year-end 2010 and work to eliminate by year-end 2015 both
plant emissions and product content of PFOA, PFOA precursors, and related higher homologue chemicals. EPA intends to propose a regulation in 2012 that would close any loopholes in the
Stewardship Program such as treated article imports.
