Elemental Carbon and Nitrogen Dioxide as Markers of Exposure to Diesel Exhaust in Selected Norwegian Industries

Elemental carbon (EC) and nitrogen dioxide (NO2) in air as markers for diesel exhaust (DE) emission exposure were measured in selected work environments in Norway where diesel-powered engines are in use. Two hundred and ninety personal full-shift air samples were collected in primary aluminium production, underground and open-pit mining, road tunnel finishing, transport of ore, and among airport baggage handlers. EC was determined in the samples by a thermo-optical method, while NO2 was determined by ion chromatography. Highest EC air concentrations (geometric mean, GM) were found in aluminium smelters (GM = 45.5 μg m−3) followed by road tunnel finishing (GM = 37.8 μg m−3) and underground mining activities (GM = 18.9 μg m−3). Low EC air concentrations were measured for baggage handling at an international airport (GM = 2.7 μg m−3) and in an open-pit mine (GM = 1.2 μg m−3). Air concentrations of NO2 were similar in road tunnel finishing (GM = 128 μg m−3) and underground mining (GM = 108 μg m−3). Lower NO2 values were observed in open-pit mining (GM = 50 μg m−3), at the airport (GM = 37 μg m−3), and in the aluminium smelters (GM = 27 μg m−3). Highly significant (P < 0.001)...