Surfactant foam components detected for the first time
Fires resulting from airplane crashes are fought using aqueous film-forming foams (AFFF) that are formulated to act quickly by spreading a film of water over the burning fuel that subsequently extinguishes the fire. The first evidence that these foams later contaminate groundwater is scheduled to appear in the August 15 issue of the peer-reviewed journal Environmental Science & Technology, published by the American Chemical Society, the world's largest scientific society. (The report initially was published on the journal's Web site on July 3, 1999.)
Fifty-three percent of drinking water in this country comes from groundwater, according to the U.S. Environmental Protection Agency.
Until now, the fate of AFFF released to the environment at fire-training facilities and emergency response sites was unknown, says Jennifer A. Field, Ph.D., of Oregon State University. Commercial AFFF mixtures are proprietary in nature, Field says, but they are known to contain fluorocarbon- and hydrocarbon-based surfactants. Field developed an analytical method for measuring the amount of perfluorocarboxylated surfactants in ground water, and then monitored groundwater at military bases in Florida and Nevada that had fire-training facilities which were no longer in use. Concentrations were detected at these sites ranging from 0.1 to 7.1 parts per million. Samples with some of the higher concentrations actually foamed.
Unfortunately, Field notes, the stability of the fluorocarbon surfactants
that makes them good choices for high-temperature applications such as
fire-fighting has the negative effect of making them resistant to degradation
in the environment. The components measured in Field's study are thought
to be only minor components of the original fire-fighting foams, so that the
actual amount of fluorinated constituents of
Contact: Charmayne Marsh
American Chemical Society