Analysis of dust exposure during chainsaw forest operations

In 1999, the European Union proclaimed hardwood dust carcinogenic based on the classification of the International Agency for Research on Cancer (IARC) issued in 1995. The operational exposure limit (OEL) for inhalable wood dust has been set to 5 mg m-3 by EU directives, though in different countries the OEL ranges from 1 to 5 mg m-3. The objective of this study was to determine the exposure to wood dust of forest workers in chainsaw cutting and processing and suggest possible countermeasures. The study took into consideration different silvicultural treatments (coppice clear cut, conifer thinning, conifer pruning, and sanitary cut) and chainsaw fuel (normal two-stroke gasoline mix and two alkylate fuels). All the forest operations were carried out in forests located in Central Italy, on the Apennine mountain range. During the tests, 100 samples were collected by means of personal SKC Button Sampler (one sample per worker per day). The results showed that exposure to wood dust varied widely with forest operation type, while no significant difference were found for different type of chainsaw fuel. The average wood dust concentration was about 1.5 mg m-3 for all operations except coppicing, which showed a mean level of about 2.1 mg m-3. About 93% of the samples showed a concentration lower than 3 mg m-3, and in only two samples (one in conifer pruning and one in clear cut in coppice), the concentration was slightly higher than 5 mg m-3.