Fire officials, “no substitute for retardant” despite toxic metals

University of Southern California (USC) research has identified high levels of toxic metals in fire retardant. Fire officials defend common use of the chemical to coat vegetation, minimizing fire spread. They say the suppressant protects lives and property as the frequency and severity of wildfires trends up year over year.

Aerial firefighting is anticipated to continue to manage the vast size of wildland fires. Using aircraft and other aerial resources to drop fire retardant has been more effective than waterbombing. Brian Fennessy, Chief of the Orange County Fire Authority, acknowledges potential harms to the natural environment. The slurry-textured substance, even when dry, sticks to vegetation and soil — helping contain the blazes. Ground firefighting approaches may also apply chemical formulations.

Additional runoff occurs when firefighting planes are cleaned after they are used to spray gel, foam or retardant on active fires.

Dr. Daniel McCurry, lead author and Assistant Professor of Civil and Environmental Engineer, expressed concern about the runoff of these chemicals into waterways. His team will also consider the transport of metals and impacts on groundwater. His work focuses on protecting public health by improving the long-term safety of engineered water sources.

For years several geochemists have recorded significantly elevated concentrations of heavy metals in streams and rivers after fires. More study is needed to determine the impact of air pollution on vegetation, which releases metals when the vegetation is burnt.

Weather, water management and wildfire are connected. To help identify and manage associated risks, KISTERS supports comprehensive and automated environmental monitoring data management. Situational awareness of drought or severe rainfall, fire fuels, and high winds are critical to prevent fires. In addition, periodic ground- and surface water quality sampling as well as ecological surveys are essential to assess ecosystem resilience to these hazards. Contact us to discuss your ecosystem monitoring goals and challenges.