Novel Fluorinated Surfactants Discovered In Firefighters’ Blood | Chemical & Engineering News
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Web Date: February 3, 2015

Novel Fluorinated Surfactants Discovered In Firefighters’ Blood

Persistent Pollutants: New technique helps to identify unreported fluorinated compounds in fire-suppressing foams
Department: Science & Technology | Collection: Life Sciences
News Channels: Environmental SCENE, Analytical SCENE
Keywords: PFOS, perfluorinated compounds, fluorinated contaminants, firefighting foams, firefighters
Firefighting foam contains a complex mix of fluorinated compounds used as surfactants, many of which have not been identified by environmental scientists.
Credit: Shutterstock
Photo of firefighters putting out a burning bus with fire-suppressant foam.
Firefighting foam contains a complex mix of fluorinated compounds used as surfactants, many of which have not been identified by environmental scientists.
Credit: Shutterstock

Perfluorinated compounds, such as perfluorooctane sulfonate (PFOS), help firefighting foams rapidly flow over flaming liquids such as gasoline and jet fuel, cooling and quenching fires. But despite environmental scientists’ concerns about these possibly toxic compounds accumulating in wildlife and lurking in firefighters’ blood, researchers don’t know the identity of many of the chemicals in the mixtures on the market. For the first time, a new study borrows a medical research tool to pinpoint fluorochemicals in the blood of firefighters, identifying novel compounds that have never before been publicly reported (Environ. Sci. Technol. 2015, DOI: 10.1021/es503653n).

PFOS and other perfluorinated compounds are extremely persistent in the environment, and toxicological studies have linked the chemicals to kidney and bladder cancer and thyroid disease. Airports and military bases use large amounts of firefighting foams for training purposes, and in some cases, the perfluorinated surfactants have slipped into groundwater and surface water supplies, triggering drinking water shutdowns. The complex mix of largely unknown fluorinated compounds in foams included PFOS until 3M, the largest manufacturer of PFOS, voluntarily phased out the compound in 2002 because of toxicity concerns. Firefighting foam manufacturers have since replaced PFOS with shorter chain fluorinated compounds, many of which are not named by manufacturers.

To identify these mystery compounds, earlier studies have taken advantage of improved analytical techniques, such as quadrupole time-of-flight tandem mass spectrometry (QTOF-MS/MS). “But since QTOF-MS/MS generates thousands of organic compounds from an environmental sample, identifying the unknowns is like trying to find a needle in a haystack,” says María José Gómez Ramos, an analytical chemist at the University of Queensland, in Australia, and an author of the study.

She and her team realized they could isolate the unknowns using a similar strategy to ones that medical researchers use to identify unique biomarkers of diseases. In those studies, researchers might compare compounds found in the blood of cancer patients with those in a healthy control group. For the new study, the scientists compared the fluorinated surfactants in the blood of 20 firefighters with compounds in the blood of 20 students and office workers who had not been exposed to firefighting foams. Gómez Ramos figured that the compounds unique to firefighters would contain unknown fluorinated surfactants.

The scientists ran the blood samples through QTOF-MS/MS, identifying more than 3,000 organic and fluorinated chemicals. But when the research team applied a statistical analysis to the data, a clear separation between the firefighters and controls emerged. The team found nine fluorinated compounds, either exclusively or at significantly higher levels, in the firefighters’ blood. Only five of those compounds appeared in online chemical databases or in the literature. Interpreting the MS data, Gómez Ramos tentatively identified the four unknown compounds as sulfonic acids analogous to PFOS. “It is likely that the unknowns have similar properties to PFOS, such as toxicity and persistence in humans and environment,” Gómez Ramos says. But further studies on the compounds are warranted, she says.

Ian T. Cousins, an environmental chemist at Stockholm University, points out that these new sulfonic acids haven’t been found in commercial foams, so they might be metabolites. But if they are in the foams, “then we should be concerned for highly exposed groups like firefighters,” Cousins says. “We know nothing about their risks.”

Chemical & Engineering News
ISSN 0009-2347
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Tony Loro (February 4, 2015 9:09 AM)
Concerned yes. Surprised, no.
Bill Brooks (February 4, 2015 11:31 AM)
This is important research, not just for firefighters, but for the millions who are exposed to PFOAs, their breakdown products, and metabolites from foods cooked in "non-stick" PFOA coated cookware. These exposures happen in the home, restaurants, and from industrial cooking processes.

Another significant exposed population is to citizens who have the misfortune of being along waterways contaminated by PFOAs, or who eat fish from these waters. Citizens of Washington, WV, and Ohio who get the fugitive and intentional emissions from Dupont are one such population.

Another such population is the Georgia and Alabama residents who are on and below Georgia's Conasauga RIver--heavily tainted with PFOAs from "Stainmaster" carpet effluents from the City of Dalton's 6,000 acre sewage spray field--a reservoir of PFOAs leaching downstream. These PFOAs slide right through the city's wastewater treatment plants--designed for "treating" biological treatment, not exotic halogenated compounds. The few humans tested have scored some of the highest blood levels of PFOAs yet measured. Their health is declining as a result, but no responsibility is sticking to those responsible.

Read "Chemical on the Conasauga" or the Charleston Gazette's Ken Ward's blog for more...
John Wiles (February 4, 2015 1:33 PM)
The final comment by Ian Cousins warrants more detail - do firefighters use commercial foams "that new sulfonic acids haven't been found in."

And, how do firefighters clean up PFOS 'persistent in the environment' and greater risk of exposure?

My son is a captain in a municipal fire department so I am concerned.

chemist (February 5, 2015 1:14 AM)
PFOs is a persistent organic pollutant so called POPs aubstance. It is under the scope of work for the parties of Stockholm Convenntion. As far as I know US didn't ratify this convention, presumably due to strong industry influence.
Mark (February 5, 2015 6:39 AM)
We were always told how safe these were to use and years after the fact they come out with there suspicions that there are lingering compounds that are shortening firefighters lives. Wouldn't it be fantastic just once to not be used as guinea pigs for chemical companies.
To market these chemicals without testing for these hazards in advance and warning users of the after effects is willful negligence on the part of these producers and it is my greatest hope that the owners of these companies are held as accountable as war criminals are for mass death!
Norbert (August 18, 2015 2:24 AM)
Look to the site and search on "Explanatory Notes", this has a summary of the issues and concerns. BTW cookware is not "coated in PFOA" it is coated in teflon PTFE which is inert. There may be traces of PFOA when it is first produced. The problem is with the dozens of other non-inert fluorinated compounds.

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