US Geological Survey


Date of this Version



Ecotoxicology and Environmental Safety 72 (2009) 862–865; doi:10.1016/j.ecoenv.2008.09.001


Wildland fire control chemicals are released into the environment by aerial and ground applications to manage rangeland, grassland, and forest fires. Acute oral 24 h median lethal dosages (LD50) for three fire retardants (Fire-Trol GTS-R™, Phos-Chek D-75F™, and Fire-Trol LCG-R™) and two Class A fire suppressant foams (Silv-Ex™ and Phos-Chek WD881™) were estimated for northern bobwhites, Colinus virginianus, American kestrels, Falco sparverius, and red-winged blackbirds, Agelaius phoeniceus. The LD50s of all chemicals for the bobwhites and red0winged blackbirds and for kestrels dosed with Phos-Chek WD881™ and Silv-Ex™ were above the predetermined 2000 mg chemical/kg body mass regulatory limit criteria for acute oral toxicity. The LD50s were not quantifiable for kestrels dosed with Fire-Trol GTS-R™, Phos-Chek D-75F™, and Fire-Trol LCG-R™ because of the number of birds which regurgitated the dosage. These chemicals appear to be of comparatively low order of acute oral toxicity to the avian species tested.