An alternative view
Published: 31 March, 2009
Tom Cortina of the Fire Fighting Foam Coalition puts forward an alternative view on the Norwegian State Pollution Control Agency’s report on polyfluorinated organic compounds at the four fire training facilities in Norway.
The SFT study of fire training facilities in Norway confirms the findings of previous studies that the likely ultimate biodegradation products of the fluorochemicals used in currently manufactured AFFF agents are persistent, but are not considered to be significant environmental toxins. The low bioaccumulation values developed in this study reinforce previous assertions of the general safety of these products. Because these studies were done at fire training areas where foams were released uncontrolled numerous times over many years, the findings should not be used to assess the impact of a one-time use of a firefighting foam to extinguish a fire, which would result in significantly smaller contaminant concentrations. Current accepted practice is to use fluorine-free training foams whenever possible as well as to collect and treat foam discharges when fluorine-containing foams are used for training or testing. The three main fluorochemicals found in the SFT study – PFOS, PFOA, and 6:2 FTS – have been found previously in groundwater studies from fire training facilities in the United States (1). PFOS and PFOA were likely contaminants and/or biodegradation products of the ECF-based fluorosurfactants contained in AFFF agents primarily manufactured by 3M prior to 2002. 6:2 FTS is a likely contaminant and/or biodegradation product of the fluorotelomer-based surfactants contained in currently manufactured AFFF agents (manufactured since the 1970s). Neither of these compounds (PFOS or 6:2 FTS) was used directly “as is” in the AFFF agents, as was cited incorrectly in the SFT study.
As noted above they are contaminants and/or biodegradation products of the more complex fluorosurfactants that are the key functional ingredients in AFFF. Of note in the SFT study is that concentrations for all perfluorochemicals (PFCs) other than PFOS were below their limit of quantitation in all “background” soils. Therefore concern regarding potential impact on soil dwelling organisms applies only to the immediate area surrounding sites where these repeated releases occurred.
The SFT study does confirm previously reported data that 6:2 FTS is neither bioaccumulative nor biopersistent. The bioaccumulation factor (BAF) values for 6:2 FTS in earthworms from the SFT report and in rainbow trout from previous studies (2) are 100-1,000 times lower than EU regulatory criteria for bioaccumulation.
The BAF values were slightly higher for 6:2 FTS than for PFOS and PFOA in the SFT study. For this reason we would expect advocates of alternative foams to argue that 6:2 FTS has similar environmental properties to PFOS and therefore the use of fluorotelomer-based foams should be limited. We would argue that the SFT study results do not change the basic conclusion from a broad range of existing data that 6:2 FTS is not similar to PFOS in either its physical or ecotoxicological properties (3, 4, 5, 6). Recent studies on AFFF fluorotelomer-based surfactants likely to break down to 6:2 FTS show it to be generally low in acute, sub-chronic, and aquatic toxicity, and neither a genetic nor developmental toxicant.
Both the AFFF surfactant and 6:2 FTS were significantly lower than PFOS when tested in biopersistence screening studies that provide a relative measure of biouptake and clearance (Figure 1) (7). The body of available data on the C6-based fluorotelomer surfactants used in AFFF agents provides strong evidence of the product’s safety for its intended use in Class B fires.
On the other hand, many global environmental authorities have strictly regulated the use of PFOS due to its documented PBT properties.
In the European Union existing stocks of PFOS-based foams must be removed from service by June 27, 2011. PFOA is not likely to have come from fluorotelomer-based AFFF in any significant amounts. The fluorotelomer-based surfactants used in AFFF agents are not made with PFOA and PFOA is not used in the manufacturing process. Current unintended trace quantities of PFOA in fluorotelomer-based AFFF will be virtually eliminated under the EPA PFOA global stewardship program.
Under the program telomer producers have committed to 95 per cent reductions of PFOA, PFOA precursors, and related higher homologue chemicals by year end 2010 and are working toward the elimination of these chemicals from both plant emissions and finished products by year end 2015. Fluorotelomer-based AFFF agents are the most effective agents currently available to fight flammable liquid fires (Class B) in military, industrial, and municipal settings. They neither contain nor break down into PFOS and are not likely to be significant sources of PFCAs. They do contain fluorosurfactants that are persistent, but are not generally considered to be significant environmental toxins.
FFFC members who make fluorotelomer-based AFFF agents and fluorosurfactants are in position to meet the goals of the EPA global stewardship program years ahead of the target date with a new family of fluorosurfactants that provide the same fire protection characteristics with reduced environmental impacts.
Over the last few years much has been said and written about the effects of firefighting foam ingredients and their breakdown products on the environment. We, Dr Sthamer - Hamburg, as a manufacturer of firefighting foams, produce a wide range of foams to suit all applications from class A wetting agents to high performance AFFF and alcohol-resistant AFFF’s.
As a major supplier to the German municipal and industrial fire brigades, we are constantly asked to provide solutions for new risks and to satisfy the strict requirements of the German environmental protection agency (UBA).
The most visible user of firefighting foams are the municipal fire brigades, however, in Germany the majority use multipurpose detergent based foam which provide good class A and small class B fire protection capabilities. However with the increasing calls for bio fuels, these foams are ineffective when used on fuel spills of ethanol-enriched petrol and diesels following a vehicle accident.
In discussions with members of the UK Fire and Rescue Services, it is evident that they are having similar pressures from the UK Environment Agency, and are having to look at all aspects of firefighting foams usage and disposal of fire water runoff.
There has been a culture change within the service and each brigade is investigating:
1) the types of foams they have in stock
2) Its effectiveness on Class A and B fires
3) Ease of cleanup post discharge.
4) Their historical usage of foams.
5) Environmental data on COD and BOD.
Some brigades have also started sharing knowledge which will lead to better understanding of where they are and what they have to do to achieve a balanced way forward. This approach to information sharing must be rolled out to all brigades to ensure that best practice is adopted across the country. The decisions made, are made with full information and for the right reasons. We fully support the efforts of these brigades, by supplying all necessary documentation on request.
In line with these efforts, we have recently launched a new environmentally-friendly fluorine free alcohol-resistant foam, which is ideal for fire brigades increasingly dealing with conventional and ethanol enhanced fuel incidents.
Although it was launched only three months ago, we have received much interest and we are already involved in detailed discussions with a number of brigades. Proof indeed that interest in this type of product from the municipal sector is on the increase.
