Evaluation of dermal exposure to pesticides in greenhouse workers

According to a survey carried out at the Department of Agricultural Engineering of the Catania University, farmers in the province of Ragusa realise greenhouse plant protection by means of 15-20 spray applications, delivering volume rates ranging from 900 up to 1800 L/ha, according to the plants growth. The most widespread machineries are handheld high pressure spray lances, which expose the operators to high risks of dermal contamination. This paper reports the results of some trials aimed at measuring the dermal exposure of operators during spray applications to tomato plants full developed. Experimental tests were carried out comparing two handheld spray lances, two working pressures (1 and 2 MPa), and two walking directions (forward and backwards). The spray lances were a “Yamaho C-6” lance with two nozzles, each with two orifices, and a high pressure spray lance with one 1.5 mm diameter turbulence nozzle. The results showed as the dermal operator exposure could be greatly reduced performing spray applications walking backwards: with a reference volume rate of 1000 L/ha, the operator contamination was in fact 223 mL/h walking forward and 26 mL/h walking backwards. Moreover, when he walked forward, the greatest unitary depositions were on the right hand (0.550 μL/cm2), the right foot (0.389 μL/cm2), and the right arm (0.352 μL/cm2), while when he walked backwards, they were on the feet (right = 0.080 μL/cm2 and left = 0.075 μL/cm2). Fixing the operator movement (backwards), pressure and type of sprayer didn’t affect exposure: it was on average 40 mL/h, mainly located on upper limbs (51.5%).