URINARY 3-HYDROXYBENZO[A]PYRENE AS A BIOMARKER OF EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS: AN APPROACH FOR DETERMINING A BIOLOGICAL LIMIT VALUE

Atmospheric and biological monitoring was carried out on 38 people exposed to polycyclic aromatic hydrocarbons in different workplaces. The relationship between the atmospheric BaP and the 3-OHBaP urinary concentration peaks was determined. To avoid misinterpretation due to dermal exposure, only people with mainly respiratory exposure were chosen. The selection was carried out from observation of working conditions and from urinary data. For the limit value determination, BaP concentrations higher than 5,000 ng/m³ were discarded and the 3-OHBaP values were adjusted to a 8 h exposure time. A close relationship was observed between the two variables: n = 17, r = 0.89, p < .0001 (C 3-OHBaP = 0.001835*C BaP + 0.1729). To estimate the 3-OHBaP limit concentration, the French recommended value of 150 ng/m³ for atmospheric BaP was used. The corresponding 3-OHBaP was 0.45 nmol/mol creatinine. This value could be used as a sound basic element for determining a biological exposure index.     

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.     

EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS AND EXCRETION OF URINARY 3-HYDROXYBENZO[A]PYRENE: ASSESSMENT OF AN APPROPRIATE SAMPLING TIME

Biomonitoring of workers was carried out in seven workplaces—two aluminium plants, an electrometallurgy plant, two carbon brake disk factories, a creosoting workshop, and an artificial target factory—to assess exposure to polycyclic aromatic hydrocarbons (PAHs). At least all the 48 h voided urine samples were collected, the first urine before the preshift at the beginning of the week and the last one after the preshift of the third day. The 3-hydroxybenzo[a]pyrene (3-OHBaP) and 1-hydroxypyrene (1-OHPy) in each urine sample were then analyzed separately by methods developed by INRS. Concentration profiles were determined. They indicate a considerable lag between the maximum excretion of the two metabolites. Including the previously published data obtained with workers exposed to PAHs, this varies from 3 to 24 h (mean lag = 15 h, n = 42). In order to determine the most appropriate sampling time for 3-OHBaP, the time of the 3-OHBaP maximum concentration is compared with the preshift.