Airborne insecticide residues after broadcast application for cat flea (Siphonaptera: Pulicidae) control.

Airborne residues of chlorpyrifos, propetamphos, and permethrin were measured up to 50 h after broadcast treatment for cat flea, Ctenocephalides felis (Bouché), control in residences. Type of insecticide, time after treatment, ventilation regime, and height above floor significantly affected airborne residues. Before spraying chlorpyrifos, residues were low or undetected. In nonventilated residences, chlorpyrifos residues peaked 0-6 h after treatment at 38 ng/liter, then slowly declined through 50 h. In ventilated residences, chlorpyrifos residues peaked from 2 to 10 h after treatment at 25-27 ng/liter, then declined to 8 ng/liter at 50 h. Propetamphos and permethrin residues in nonventilated residences peaked at 0-2 h at 32-40 and 40-44 ng/liter, respectively. Propetamphos peaked at 12-17 ng/liter at 0-2 h in ventilated residences. Permethrin was not detected in any of the samples in ventilated residences. Maximum airborne concentrations were 74 ng/liter chlorpyrifos, 49 ng/liter propetamphos, and 54 ng/liter permethrin.