Biological monitoring of exposure to polycyclic aromatic hydrocarbons among people leaving nearby an aluminium smelter in the province of Quebec

Background. The objective of the study is to estimate the exposure to pyren e, an indicator of polycyclic aromatic hydrocarbons (PAHs) in the general e nvironment, by using the internal dose of 1-hydroxypyrene (1-OHP) among peo ple living nearby an aluminium smelter in the Monteregie area, Province of Quebec, Canada. Methods: This cross-sectional study was done in November and December 1998 Participants were randomly selected according To their environmental exposu re to PAHs and were distributed according to three exposure levels (high, l ow, none). Altogether 121 non smokers aged between 18 to 70 years were recr uited for the study. Persons occupationally exposed to PAHs or using tar-ba sed medications were excluded Those with personal medical conditions that a ffect the metabolism of pyrene were also excluded Urine samples were taken in the morning and analysed by gas chromatography and mass spectrometry (GC -MS) to determine the concentration of the metabolite, 1-OHP. Results: Among the exposed group (n=78), the geometric mean of urinary conc entration of 1-OHP was 0.073 mu mol/mol creatinine compared to 0.060 mu mol /mol creatinine for the control group (n=40). The difference did not reach statistical significance (p=0.09): Geometric means among the three groups o f exposure (high, low none) were respectively 0.079, 0.067 and 0.060 mu mol /mol creatinine (p=0.13). Accounting for personal risk factors, such as die t, passive smoke, use of wood heating and time spent at home during the thr ee days prior to urine sampling, did not change previous results. Conclusion: This study indicates that the environmental levels of PAH produ ced by this factory are low and do not contribute significantly to the body burden of PAH as measured by 1-OHP.