An investigation into the use of Class A fire- fighting foams to control the spread of whirling disease by wildland fire-fighting activities

Whirling disease is a serious problem that impacts wild and hatchery salmonid stocks across the globe. Whirling disease is caused by a microscopic parasite, Myxobolus cerebralis, with a complex life history involving both salmonid and oligochaete worm hosts. In this study, we investigated the capability of wildland firefighting foams to inactivate M. cerebralis by indirect methods. Specifically, we tested the effectiveness of firefighting foams as disinfecting agents against surrogate organisms (E. coli and coliphage) in bench-scale laboratory experiments. The USFS firefighting foams tested in this study did not inactivate E. coli or coliphage during a 60-min contact time at a 10% mix ratio. We did not examine whether firefighting foams were effective at displacing bacterial and viral organisms when treated as a surfactant. Nevertheless, we conclude that continued research into the use of dilute fire retardant foams to inactivate aquatic invasive microorganisms is not warranted.