Assessment Of Occupational Exposure To PAHsIn A Coke-plant By Biological Monitoring

In 2002 a criminal law case was filed by the General Prosecutor in Taranto, accusing the management of the second largest steel plant in Europe of criminal misbehaviour in the industrial hygiene procedures at the batteries 3 through 6 of the coke oven plant. Some of the authors were appointed by the Taranto prosecutor to assess occupational exposure to concentrations of a wide range of volatile coal tar pitch compounds. The present project aims at validating the biological monitoring of carcinogen (namely PAHs) exposure by performing environmental monitoring at the same time. Personal air samples of the workers were taken during the morning shift. The job activities were recorded by occupational physicians. On the same days, spot urine samples before and after the shift were collected to determine 1hydroxypyrene as internal dose biomarker. Confounding factors, such as diet and smoking habits, were checked by means of a questionnaire. The PAH concentrations in the breathing zone air of coke-oven workers ranged from 20.40 mg/m 3 to 76.68 mg/m 3 , with a median of 30,00 mg/m 3 . The concentration of 1OHP in the pre-shift samples ranged from 0.01µmol/molcreat to 1.32 µmol/molcreat with a median of 0.33, and in post-shift from 0.01 µmol/molcreat to 31.04 µmol/molcreat, with a median of 2.41. The correlation between total PAH and 1HOP levels has been calculated, showing a correlation coefficient r= 0.31(p<0.05). The low correlation is partly due to variation in the working practices during environmental sampling, resulting in lower environmental exposure as well as to the poor sampling and analytical procedures used by the subcontracting industrial hygiene firm. The study shows that biological monitoring is more reliable then environmental monitoring in the assessment of occupational