Urinary 1-hydroxypyrene in children living in city and rural residences in Denmark

AimsThe present study aims to assess the biological uptake in children of polycyclic aromatic hydrocarbons measured as 1-hydroxypyrene in urine from children living in city and rural residences.Methods103 children living in Copenhagen and 101 children living in rural residences of Denmark collected urine samples Monday to Friday morning. Each day, the family filled in a printed diary that included questions about the time and activity patterns of the child. Multiple regression analyses were used to identify predictors of the excreted 1-hydroxypyrene level.ResultsDuring the week, the children excreted on average 0.07 [95% CI: 0.01–0.41] μmol urinary 1-hydroxypyrene per mol creatinine. Children living in urban residences excreted 0.02 [95% CI: 0.01–0.05] μmol more 1-hydroxypyrene than children living in rural residences. This was confirmed in the multiple regression analysis showing a 29% (95% CI: 2–64%) higher excretion among urban children than rural children. Moreover, the regression analysis showed that for each hour per day spent outside the children excreted 58% (1.58 [1.22–2.03]) more 1-hydroxypyrene in urine.ConclusionThe present study indicates that children living in urban residences are more exposed to PAH than children living in rural residences. Time spent outdoors increased the excretion of 1-hydroxypyrene, which was most evident among urban children. Higher concentrations of ambient air pollution in urban areas may explain this finding. No influence of environmental tobacco smoke, cooking habits, and heating facilities was detected.