Urinary hydroxylated metabolites of polycyclic aromatic hydrocarbons as biomarkers of exposure in asphalt workers

BACKGROUND: Fumes and vapours released during laying of hot asphalt mix have been recognised as a major source of exposure for asphalt workers. OBJECTIVES: We investigated the relationships between inhalation exposure to asphalt emissions and urinary biomarkers of polycyclic aromatic hydrocarbons (PAHs) in asphalt workers (AW, n=75) and in ground construction workers (CW, n=37). METHODS: Total polyaromatic compounds (PAC) and 15 priority PAHs in inhaled air were measured by personal sampling. Hydroxylated PAH metabolites (OH-PAHs) (2-naphthol, 2-hydroxyfluorene, 3-hydroxyphenanthrene, 1-hydroxypyrene, 6-hydroxychrysene and 3-hydroxybenzo[a]pyrene) were determined in urine spot samples collected in three different times during the work week. RESULTS: Median vapour-phase PAC (5.5 microg m(-3)), PAHs (