EXPOSURE TO POLYCYCLIC AROMATIC-HYDROCARBONS IN COAL-LIQUEFACTION WORKERS - IMPACT OF A WORKWEAR POLICY ON EXCRETION OF URINARY 1-HYDROXYPYRENE

Objective-This study was undertaken to assess whether contaminated per sonal clothing worn beneath a coverall (normal workwear) is a source o f potentially significant dermal exposure to polycyclic aromatic hydro carbons (PAHs) in coal liquefaction workers. Methods-An intervention s tudy was conducted over a two week period involving 10 workers that re flected the range of activities performed at the factory. A cross over design was used to examine the influence of normal workwear (personal clothing worn beneath a coverall) and intervention workwear (new cove rall, shirt, trousers, underwear, socks, and boots) upon excretion of urinary 1-hydroxypyrene (1-OHP) and skin pad deposition of pyrene. Res ults-The impact of intervention was noted in three ways: (1) A notable reduction (55%) in the mass of 1-OHP excreted on the first day of the intervention phase was found. The median reduction in mass excreted ( 22.7 nmol) was significant from zero at the 5% level; (95% confidence interval (95% CI) 9.5-40.8 nmol). (2) A notable reduction (82%) in ski n pad deposition of pyrene on the first day of the intervention phase was found. The median reduction of 13.20 ng.cm(-2) was significant fi om zero at the 5% level; (95% CI 7.3-26.4 ng.cm(-2)). (3) About a 50% reduction in 1-OHP concentration over the working week occurred during the intervention phase; an increase of 2.07 mu mol/mol creatinine was found from the start to the end of the work period during the interve ntion phase compared with an increase of 4.06 mu mol/mol creatinine du ring the normal phase. This reduction was not significant at the 5% le vel. Conclusion-The results indicate that on the first day of the work ing week investigated, significant reductions in absorbtion (as measur ed by excretion of urinary 1-OHP) and deposition of PAHs (as measured by skin pad deposition of pyrene) can be effected by improvements in w orkwear policy. The impact of the improved workwear regimen was also d etected by reduction in spot urinary 1-OHP concentrations, although th is effect was less pronounced. One implication of the findings is that exposure to PAHs may arise from workers' own contaminated personal cl othing. As a consequence of this study an improved workwear policy has been implemented at the factory.