Some observations on the kinetics of urinary 1-hydroxypyrene in workers exposed to PAHs and its use to assess exposure

Data on the toxicokinetics of urinary 1-hydroxypyrene (OHP) elimination in workers exposed to PAHs were critically examined and led to the conclusions that half-lives from on-site studies are actually shorter (6-9 h) than the generally reported values. It is demonstrated that the renal elimination a nd excretion kinetics of OHP and urinary creatinine follow a similar patter n. The findings set the sound bases for adjustment of OHP concentrations to creatinine and therefore justify the corrections which have been applied. Additionally, urinary OHP determinations were used to evaluate the efficien cy of respiratory protective equipments. In workers equipped with Airstream (R) helmets, the excretion levels of OHP are clearly in the background conc entrations compared with levels in those without any protection when the sk in penetration route were inhibited. The efficiency of the helmets may be h igher than 95%. In practice, the notion of protection factor is preferred a s the efficiency is also dependent on workers behavior.