Air Immissions of Volatile Aromatics

The extremely high values in Sheffield and London are due to the fact that measurements were taken in narrow streets on a level with automobile exhausts. In the case of the industrial sites, air samples were taken at a distance of approximately 100 m from the factory. Considering the vertical distribution, the maximum toluene and xylene concentrations are found at a height of 140 m, but here temperature inversion situations also play a role [150]. Environmental research into pollution by volatile aromatics as a result of vehicular traffic is being conducted in numerous locations (see, for example [13, 142, 151-155]). Other groups are engaged in examining the transport of pollutants [66] into unpolluted areas and any 

City Benzene Toluene Xylenes Higher alkyl benzenes 

1967/71 average values [12,13,139] Zurich, average values of 8 locations. 0.04-0.06 0.03-0.06 0.05 

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