Polycyclic aromatic hydrocarbons exposure assessment and biological monitoring of asphalt blend workers

Asphalt-blending workers directly expose to asphalt which contains high level of polycyclic aromatic hydrocarbons (PAHs) in the meantime, the health effects on those workers were concerned. 90 asphalt-blending workers were recruited as exposure group and 40 adults with no PAH exposure relative working experiences served as control group. Individual PAH exposure levels of exposure workers were determined by the sampling method that was suggested by US/NIOSH No.5506. Urine sample of each participant was collected to measure urinary 1-hydroxypyrene (1-OHP). HPLC with fluorescence detector was performed to determine the levels of airborne PAHs and urinary 1-OHP. Exposure group was divided to 3 subgroups: field group workers were in charge with mixing the asphalt; operating group workers operated machines; management group workers controlled the quality of field. The average levels of total PAHs were 2456.31 ng/m3, 1779.34 ng/m3, and 901.67 ng/m3 for field group, operating group, and management group, respectively. Mean values of BaP concentration in particle of each group were 2.70 µg/g, 1.58 µg/g and 2.25 µg/g, and the gaseous and particle-bound (G/P) ratios of BaP were 0.57, 1.25 and 0.2, respectively. The average concentration of urinary 1-OHP of exposure workers was 0.17 µmol/mol creatinine and was 3.4 fold higher than that of control group (0.05 µmol/mol creatinine, p<0.05). Urinary 1-OHP in smokers was 1.26 fold higher than non-smoker among management group (p<0.05). We confirmed asphalt-blending workers exposed to high levels of PAHs and it influenced the urinary 1-OHP levels significantly.

Key words：asphalt-blending manufacturing workers, PAHs, biological monitoring