Evaluation of respirable dust exposure during hazelnut and chestnut mechanized harvesting.

Atmospheric dust is defined in different ways but the most used classification are “total suspended dust” (T.S.D) and “particulate matter” (P.M.). A further distinction within the T.S.D. is about inhalable and respirable dust. Inhalable dust has an aerodynamic diameter between 5 and 10 m, while respirable dust presents a diameter between 0,5 and 5 m. Beside the dimension, the danger about dust regards other factors, like: concentration, chemical composition, individual absorption characteristics and exposure time. The mechanized harvesting of nuts, like hazelnuts and chestnuts, is carried out with specific machines that can be classified in three different types: pulled vacuum harvesters with aspirating tubes; pulled or tractor mounted harvesters with automatic picking system; self-propelled harvesters (aspirating or picking). In spite of installation of dust limitation devices, some studies have shown that dust concentration is still more elevated (up to 10 times) than the maximum limits indicated by the American Conference of Governmental Industrial Hygienists (A.C.G.I.H.). The objective of the present study is to evaluate the level of risk at which operators, during nut mechanized harvesting and using modern machines, are really exposed. In order to carry out this survey the data have been collected among some farms of the province of Viterbo (Italy); the farms selected have heterogeneous characteristics so that it is possible to obtain representative results for each type of working site and ground