Potential dermal and inhalation exposure to chlorpyrifos in Australian pesticide workers

Chlorpyrifos inhalation, dermal exposure and working practices of 28 pesticide applicators in Western Australia were assessed during a series of single property applications of a 0.5% (n = 2) or 1% (n = 26) concentration of active ingredient in water solution, Deposition on new cotton gloves worn beneath applicators' usual protective gloves was 2.4 (range 0.12-86.1) mg h(-1). Median deposition of chlorpyrifos onto a new cotton overall worn over other clothing (24 sections removed, corrected for body proportions) was 11.1 (range 0.2-41.9) mg h(-1). Deposition onto seven patches taped to the applicators' skin was 0.04 (range 0.01-4.7) mg h(-1). Inhalation concentration was 5.7 (range 0.7-219) mug m(-3) time weighted average, In one group of 17 applicators' applying to existing properties, breathing zone air concentration correlated (P < 0.05) with ambient air temperature (15-38 degreesC). The questionnaire results (29 respondents) indicated applicators' practices led to increased exposure, in particular concerning poor usage and condition of protective equipment and a high frequency of splashes and spills onto the body, Prevention of deposition on clothing, in particular on the lower body is suggested, as well as improved working practices. (C) 2001 British Occupational Hygiene Society, Published by Elsevier Science Ltd. All rights reserved.