Exposure routes and application methods are known to be two important factors deciding degree of pesticide intoxication. Mixer-loader-applicators working at orchard farms in Kyunggi-Province iof Korea were investigated to evaluate level of exposure through respiratory or dermal route to chlorpyrifos, a representative organophosphate pesticide used in apple orchards. The level of respiratory or skin exposure was assessed using a personal air sampler or skin patch, respectively, and compared with amount of the pesticide dispersed into the ambient air nearby. Pesticide mixing works resulted in significantly higher(GM=18.1㎍/㎥, range 4.3-43.6) respiratory exposure levels than application procedures. Compared with the application by hand-held(GM=4.6㎍/㎥, range 0.4-38.2), vehicle mounted sprayer demonstrated producing relatively higher(GM=8.4㎍/㎥, range 1.9-37.6) respiratory exposure levels without statistical significance. The pesticide levels in the air were lower than the time-weighted average exposure standard. Geometric mean of total potential dermal exposure dose, which excludes exposure to hands, was 158.9 mg/hr with 74.4-273.2 range during the hand-held application, which is significantly exceeding the exposure level obtained from the vehicle mounted sprayer(GM=26.7 mg/hr, range 11.7-68.7). Whereas, the vehicle mounted sprayer brought more even distribution of the pesticide throughout the body than the hand-held. When the total potential dermal exposure doses are converted into the actual doses, all the dermal exposure levels exceed a potential health hazard guideline(210 mg/hr). The guideline was calculated considering Reference Dose by the United Stated Environmental Protection Agency and proportion of absorption through skin after pesticide´s dermal contact. overall, this study is the first report of chlorpyrifos exposure assessment associated with exposure route and application or preparation procedure, and indicated the dermal absorption as the most potential route of exposure.
II. 연구대상 및 방법