Worker exposure to paraquat and diquat

Abstract

Exposure of workers applying paraquat to fields of tomatoes and citrus, and diquat to waterways containing water hyacinths and hydrilla, was monitored with dermal α-cellulose pads attached at each of ten body locations and with personal air monitors. Estimated total body exposure for tomato applicators was apparently influenced by tractor type. Exposure levels from highest to lowest were: open tractor > enclosed cab tractor ⩾ high-clearance tractor. Citrus applicators' exposure to paraquat averaged 28.5 mg/hr and 12.2 mg/hr, with tank concentrations of 0.11% and 0.07%, respectively. Diquat applicators received minimal exposure. Respiratory exposure was <0.1% of the total body exposure in all experiments. Urine samples collected periodically for all workers were, with one exception, without detectable pesticide contamination. Use of disposable coveralls and regularly washed impermeable gloves should effectively reduce exposure.