Biological monitoring of environmental exposure to PAHs in the vicinity of a Soderberg aluminium reduction plant

Objectives-To assess environmental exposure to polycyclic aromatic hydrocarbons (PAHs) in the vicinity of a Soderberg aluminium reduction plant in Shawinigan, Canada with urinary 1-hydroxypyrene (1-OHP) as a biomarker. Methods-Urine samples were collected from 20 non-occupationally exposed subjects living less than 500 m from the plant and from 20 controls living in Trois-Rivieres, another industrial town 40 km from Shawinigan. Concentrations of 1-OHP were measured by high performance liquid chromatography (HPLC). Results-Among controls, geometric mean (range) 1-OHP concentrations were 0.046 (0.012-0.116) mu mol/mol creatinine in non-smokers and 0.125 (0.051-0.282) mu mol/mol creatinine in smokers. Among exposed subjects, values were 0.103 (0.056-0.196) mu mol/mol creatinine in nonsmokers and 0.250 (0.112-0.448) mu mol/mol creatinine in smokers. Excretion of 1-OHP was significantly higher in exposed subjects than in controls among nonsmokers and smokers (P<0.05). Conclusion-Based on urinary 1-OHP as a biomarker, it seems that living near an industrial point source of PAHs is associated with higher exposure. The health significance of this finding will require further investigation.