Dermal exposure orchard

Dermal exposure to captan and benomyl by strawberry harvesters has been the subject of several previous studies (1.2.3). This field study was designed to test a number of hypotheses and the reproducibility of dermal exposure rate measurements taken under field conditions. Most of our past studies have not been designed for a particular pesticide but were modified to accommodate the pesticide chosen by the grower to control a certain pest. In this case, the pesticide was carbaryl (1-naphthyl N-methylcarbamate) an insecticide used to control the spittlebug and leafroller. Our results could then he compared with those obtained by Maitlen and co-workers (A) who studied workers exposed to carbaryl in an apple orchard. Furthermore, attempts will be made to test possible positive correlations between age and dermal dose rate versus productivity and dermal dose rate versus age of harvesters. Difference of dermal exposure due to age or... 

Three published studies show very low Inhalation exposure. In a previous study by Jegler in Quebec ( ) workers in orchard air-blast spraying received only 0.072 mg/15 min. compared to a long-sleeved dermal exposure of 6.3 mg/15 min. Simpson ( ) found in Australia that the respirator portion of orchard air-blast spraying gave an... 

The feasibility of employing fluorescent tracers and video imaging analysis to quantify dermal exposure to pesticide applicators has been demonstrated under realistic field conditions. Six workers loaded a tracer with the organophosphate pesticide, diazinon, into air blast sprayers, and conducted normal dormant spraying in pear orchards. They were examined prior to and immediately after the application. UV-A illumination produced fluorescence on the skin surface, and the pattern of exposure was digitized with a video imaging system. Quantifiable levels of tracer were detected beneath cotton coveralls on five workers. The distribution of exposure over the body surface varied widely due to differences in protective clothing use, work practices and environmental conditions. This assessment method produced exposure values at variance with those calculated by the traditional patch technique. 

Dermal Route. In orchard applications the dermal route of exposure has been established as the major one (2, 3). Durham... 

Inhalation Route - Estimation of Aerosol Contact. The inhalation route has been shown to be considerably less important than the dermal route in the exposure of orchard workers (4). 

Paraquat. Paraquat is a widely used herbicide in cotton and potato culture, on orchard floors, and in landscape maintenance. There have been persistent reports of paraquat poisoning, mostly from ingestion both intentional and accidental, but also from dermal contact. There have also been reports linking paraquat to chronic intoxication, particularly in pulmonary disease from inhaling paraquat aerosols. In addition to food residue analysis in support of tolerance, worker exposure samples and ambient environmental samples are also of great interest. 

Table I. Dermal/Respiratory Exposure for Applicators During Airblast Spraying in Orchard...

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