Potential dermal exposure to operators applying pesticide on greenhouse crops using low-cost equipment

During pesticide application, operators are exposed to chemical products. Dermal exposure has been reported as the principal means of exposure for growers. In the present work, potential dermal exposure (PDE) has been assessed when using new low-cost equipment (a knapsack with a vertical spray boom) and compared to a hand-held spray lance, which is the equipment most widely used by growers in greenhouses. Two sprayers were used, a hand-held spray lance with four twin flat-fan nozzles and a knapsack fitted out with a vertical spray boom containing 3 pairs of twin flat-fan nozzles. Three applications were carried out and compared, one with the spray lance walking backwards (the reference application), and two with the spray boom - the first stopping at the turns and the second with no stopping. The patch method (19 position on the body) and tartrazine (the tracer) were used to assess de PDE. Each application tested was replicated three times. The results show that the knapsack with the vertical boom should not be used walking continuously along the greenhouse rows because the total PDE (1637.12mL 1000L^-1) is greater than in the rest of the configurations tested. If the operator stops at the turns for a few seconds, allowing the previously sprayed droplet cloud to dissipate, the level of exposure decreases significantly (324.63mL 1000L^-1), providing similar results to the reference application with the spray lance walking backwards (292.25mL 1000L^-1).