Occupational exposure to permethrin during its use as a public hygiene insecticide

Permethrin is an active ingredient found in many public hygiene insecticide products and exposure to it was assessed in a survey of 45 professional users. The exposures measured were over a wide range, with more than a 100-fold difference between average levels and the highest levels. Dermal contamination was evident on 93% of the operators, the highest contamination resulting from the use of leaking application equipment, demonstrating that proper maintenance of equipment is vital. Where the insecticide was applied at ground level most contamination was on the legs, indicating the importance of appropriate footwear. Contamination of the hands occurred despite the use of protective gloves, higher levels of contamination occurring when liquids were used. Dermal contamination was not always the principle route of exposure, and high airborne concentrations were linked with use in confined areas. Airborne concentrations were also associated with the physical form of the product used and the treatment method. To help in assessing the effectiveness of protective clothing and control measures, biological monitoring was carried out. Monitoring of metabolites in urine showed that systemic uptake occurred but evidence from toxicological studies indicates that the levels found were well below those considered to cause harm.