How much permethrin comes off the clothing when laundered?
A strong bond is formed between permethrin and most fabrics. In fact, some insect repellency was observed in military uniforms following 50 launderings. However, the uniforms were treated using an absorption method instead of the aerosol can. In studies performed by the U.S. Army, about 20 to 30 percent of the permethrin treatment was removed after the first laundering. Thereafter, about 3 to 5 percent was lost to each cycle through ten launderings.