Dry-cleaning solvent (tetrachloroethylene) and the dry-cleaning procedures were studied in the refurbishment of chlorpyrifos-contaminated clothing. Also evaluated were solvent-based pretreatments followed by laundering. Fabrics were a 100% cotton and a 50% cotton/50% polyester each either with a renewable, soil-repellent finish, or unfinished. Field strength chlorpyrifos (0.5% active ingredient), prepared from emulsifiable concentrate formulation, was pipetted onto specimens which were then dry-cleaned or laundered following solvent pretreatment. Transfer of pesticide from contaminated to uncontaminated fabric specimens was also studied.
Dry-cleaning treatments were most effective, with less than 1% chlorpyrifos residue remaining on fabric specimens. Mechanical agitation was an aid in chemical removal. Pesticide transfer to the uncontaminated fabrics was minimal, but did occur. Pretreatments, followed by laundering, were less effective than dry-cleaning procedures.