Evaluation of the use of 1-nitropyrene, pyrene, and 1-hydroxypyrene as markers of diesel exhaust exposure in underground mining: Results from the biomodem study

The exposure to diesel exhaust was studied in underground mining of oil shale in Estonia. The purpose of this study was to evaluate different approaches to exposure assessment. Fifty men who drove diesel-powered excavators underground were compared with 50 surface workers who had no known occupational exposure to diesel exhaust. Samples of respirable air were analyzed for 1-nitropyrene and pyrene. Urine samples were collected at the start and after the first and the last shift of the same week, and were analyzed for 1-hydroxypyrene. Although ambient monitoring of 1-nitropyrene indicated a relatively high exposure of underground workers to diesel exhaust compared to surface workers (approximately 10-fold higher), only a small increase in the excretion of 1-hydroxypyerene was observed. Nonoccupational exposures such as smoking, recent consumption of grilled food, and recent proximity to an open fire had a greater impact on urinary excretion of 1-hydroxypyrene than occupational exposure to diesel exhaust.