Environmental exposure of small children to polycyclic aromatic hydrocarbons

Objectives: The aim of the study was to assess the intake (by various route s of exposure) of polycyclic aromatic hydrocarbons (PAH) by children living in a Czech city, and its effect on excretion of 1-hydroxypyrene (1-OHP) in summer and winter periods. Methods: Four groups of children (3-6 years old ) were chosen: (1) two groups from a kindergarten situated in the city cent er with a higher traffic density ("polluted" area); (2) two groups from a k indergarten situated in a green zone of the same city ("non-polluted" area) . Food consumption was recorded in all children and PAH intake from foodstu ffs was estimated. Ambient air samples were collected from the playground a nd inside the kindergartens. Soil samples were collected too. Morning and e vening urine samples were collected during sampling days. Results: In both seasons, the mean outdoor total PAH concentration (sum of 12 individual PAH ) in the "polluted" area was approximately three-times higher than that in the "non-polluted" area. Indoor concentration in the "polluted" area was mo re than six-times higher than that in the "non-polluted" area in summer, an d almost three-times higher in winter. The same trend was observed for pyre ne and for the sum of carcinogenic PAH. The contribution to the total pyren e absorbed dose from food consumption was much more important than that fro m inhalation and from ingestion of soil dust. Significantly higher urinary concentrations of 1-OHP (evening samples) were found in children from the " polluted" kindergarten in both seasons. The number of significant relations hips between 1-OHP and pyrene absorbed dose was weak. Conclusions: Food see ms to be the main source of total pyrene and total PAH intake in small chil dren, even under relatively higher air PAH exposure in the city. Estimated pyrene ingestion from soil had a negligible contribution to the total pyren e absorbed dose. Urinary 1-OHP seems to be an uncertain (non-sensitive) mar ker of the environmental inhalation exposure to pyrene (PAH) if the polluti on of air by pyrene (PAH) is not excessive and the pyrene (PAH) dose by thi s route is much less than by ingestion. Usefulness of the urinary 1-OHP as an indicator of overall environmental exposure to PAH needs further investi gation.