Occupational exposure to carcinogenic wood dust in two Italian biomass power plants.

In this study we monitored exposure to airborne dust in workers performing various tasks at two biomass-fuelled thermal power plants (27 and 46 MW) over six years. The plants are mainly fuelled by forest wood chips and, to a lesser extent, by agro-food products, with annual consumption of about 300 and 450 kt. We focused on inhalable wood dust because of its potential carcinogenicity to humans. Worker exposure was assessed with personal samplers, drawing ambient air in their breathing zone to determine the real external dose of dust inhaled by the workers and the associated occupational risk. With but a few exceptions, exposure to inhalable wood dust complies to the limit of 2 mg/m given by the European Directives 2019/130 and 2017/2398. Further investigations will be necessary to obtain a larger number of measurements that allow for a more robust statistical investigation of the results.