CORRELATION BETWEEN WORK PROCESS-RELATED EXPOSURE TO POLYCYCLIC AROMATIC-HYDROCARBONS AND URINARY LEVELS OF ALPHA-NAPHTHOL, BETA-NAPHTHYLAMINE AND 1-HYDROXYPYRENE IN IRON FOUNDRY WORKERS

In two Danish iron foundries the concentration of polycyclic aromatic hydrocarbons (PAH) in 24 personal air samples of workers employed in s elected processes, i.e. melters, melted iron transporters, casters, ma chine molders, hand molders, shake-out workers and finishing workers, were measured and correlated to levels of 1-hydroxypyrene, alpha-napht hol and beta-naphthylamine in the urine of exposed workers. The highes t total airborne PAH concentrations (sum of 15 selected PAH compounds: 9.6-11.2 mug/m3) were associated with casting, machine molding, and s hake-out. The highest concentrations of the sum of six selected airbor ne carcinogenic PAH compounds were found for melting, casting and mach ine and hand molding. As seen in other working environments involving low-level PAH exposure, the content of naphthalene was high, in genera l exceeding 85% of the total content of PAH compounds. The present stu dy demonstrates that 1-hydroxypyrene is a useful and direct biomarker of low-dose occupational exposure to PAH compounds. Molding and castin g had the highest pyrene levels in iron foundries. Furthermore, the da ta shows that levels of beta-naphthylamine in urine are significantly elevated in iron foundry workers. Hand molders, finishing workers and truck drivers tended to have the highest levels. Concerning alpha-naph thol, the highest concentrations were measured in urine from casters a nd shake-out workers. With regard to epidemiologic studies demonstrati ng that molders and casters have a higher risk of lung cancer, the pre sent study suggests that the elevated risk may be due to exposure to c arcinogenic PAH compounds in iron foundries, particularly in some high -risk work processes, e.g. casting and molding. In addition, the prese nt study suggests that biological monitoring of 1-hydroxypyrene and be ta-naphthylamine may be used to estimate the individual exposure, whic h seems to be correlated with exposure during individual work processe s.