Occupational exposure to PAHS - Biological monitoring of hydroxylated metabolites

The exposure to PAHs of 67 workers occupied in a graphite-electrode producing plant has been investigated. Beside conventional ambient monitoring biological monitoring was performed using a newly developed coupled-column HPLC method to determine beside 1-hydroxypyrene 1-, 2+9-, 3- and 4-hydroxyphenanthrene. The excretion of phenanthrene metabolites correlates significantly with the amount of 1-hydroxypyrene in urine. The relationship between internal and external dose was investigated. The concentration of 1-hydroxypyrene depends significantly upon each PAH concentration measured in air as well as upon their sum. A benzo(a)pyrene concentration in air of 2 mu g/m(3), which is the Technical Exposure Limit in Germany, leads to a 1-hydroxypyrene excretion between 20 and 74 mu g/g creatinine.