Assessment of multipathway exposure of small children to PAH.

The aim of study was to assess the uptake of polycyclic aromatic hydrocarbons (PAH) by children living in a city and its effect on 1-hydroxypyrene (1-OHP) excretion. Two groups of children (n=11 and 13; 3-6 years old) were chosen: (1) a group from a kindergarten situated near a road with a high traffic density ('polluted' area); (2) a group from a kindergarten situated in a green zone ('non polluted' area). Food consumption was recorded in all children and PAH uptake from foodstuffs was estimated. Ambient air samples were collected on the playground and indoor of kindergartens during 3 days in summer 1997. Soil samples were collected on the playground. Urine samples were collected in the morning and in the evening. Mean outdoor total PAH concentration (sum of 12 individual PAH) in 'polluted' area was 12 times higher than that in 'non polluted' area (22.9 vs. 1.9 ng/m(3)). However, indoor concentrations were similar (3.0 vs. 2.1 ng/m(3)). The same trend was observed for pyrene concentrations. The contribution to the total pyrene absorbed dose from food consumption (estimated daily absorbed dose of 167 and 186 ng, respectively, in 'polluted' and 'non polluted' area) was much more important than that from inhalation (8.4 and 5.4 ng, respectively) in both areas. The estimated daily absorbed doses of pyrene from the soil were 0.061 and 0.104 ng in 'polluted' and 'non polluted' kindergarten, respectively, which correspond to 0.032 and 0.059% of the total absorbed dose. Higher urinary concentrations of 1-OHP were found in children from 'polluted' kindergarten. In conclusion, the food seems to be a main source of the total pyrene and total PAH uptake in small children, even under a relative high PAH air exposure in the city. Pyrene concentration in soil had a negligible contribution to the total pyrene absorbed dose. Usefulness of the urinary 1-OHP as an indicator of the environmental exposure to PAH needs further research.