The aims of this study were to classify as safe or unsafe the work conditions under which a commercial formulation of paraquat at 0.5% was applied and the loading tanks used for post-emergence weed control of a sugar cane crop, using a hand -held, pressurized sprayer or Pulmipur hand-held backpack sprayer; to determine the effect of variations in herbicide application at four Sugar and Alcohol Plants using a pressurized backpack sprayer on worker exposure to paraquat ; to assess the efficacy of personal protective equipments (PPEs) under these work conditions; and to evaluate the extent of drift and PPE efficacy against drift. Dermal and respiratory exposure of the workers was determined and used to calculate the margin of safety (MOS). The MOS values were utilized to classify these work conditions as safe (MOS e" 1) or unsafe (MOS < 1). To evaluate the drift resulting from application on the crops and the efficacy of protective gear against it, the following treatments were studied: a commercial formulation of paraquat at 0.5% in the spray mix, applied with the hand-held backpack sprayer, with and without protective hat against drift, and with pressurized backpack sprayer, with and without protective shield against drift; a commercial formulation of pure paraquat with Pulmipur; a commercial formulation of glyphosate at 1% (utilized as standard treatment for comparison) applied with the pressurized backpack sprayer and shield, and pure glyphosate with Pulmipur; and control without application. The two activities with Pulmipur produced the greatest dermal exposures due to formulation handling and were considered unsafe without the use of PPEs and safe with the PPEs. The activities using hand-held or pressurized backpack sprayer were safe with or without PPEs. The great differences in the dermal exposures of the workers were due to the differences in daily work time and number of workers in the teams of the Sugar and Alcohol Plants. The hat type protective gear against drift was effective under paraquat application whereas the shield was not.
sugar cane; drift control; personal protective equipment-PPEs; occupational intoxication risk; work safety
