Vertical profiles of lead above a street

city streets form a canyon from which dispersion of pollutants occurs only rather inefficiently. In a recent study [20] both inorganic and vapour-phase 

Stockholm 3 Wide busy city centre streets 6 

Stockholm 2 City centre (a) crossing (b) queue of traffic 5 

From rural-city centre Roadside, on kerb Roadside, 5 m from kerb Works exit traffic lights, traffic (1) arriving (2) leaving Tunnel Tunnel Petrol station Petrol station Multi-storey car park Car park 

Sources of data are cited by Harrison, Laxen and Birch [12]. 

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