Outdoor spatial distribution and indoor levels of NO2 and SO2 in a high environmental risk site of the South Italy

In the frame of the project EDOC@WORK3.0, Education and Work on Cloud, a monitoring plan has been carried out in the highly industrialized town of Taranto (one of the most polluted sites of Italy) in order to investigate contemporary indoor and outdoor concentrations of NO2 and SO2 by passive sampling devises (Radiello). Simultaneously indoor and outdoor samplings of NO2 and SO2 were performed from 2nd November 2015 to 2nd December 2015 in nine sites scattered in the investigated area at different quotes and distances from the industrial complex. Our findings show substantial differences between the spatial distributions of the two pollutants and support the hypothesis of two different prevalent sources for NO2 and SO2. In particular, we find diffusive sources of NO2 linked mainly to the vehicular traffic and secondarily to industrial sources. In contrast, SO2 was mainly associated to industrial sources present in the area, representing also a proxy of the mixture of air contaminants associated to industrial processes. Our hypothesis is also confirmed by analysis of data measured by ARPA air quality monitoring stations. Comparison between indoor and outdoor concentrations confirms that outdoor pollutants infiltrate to indoor environments, moreover it highlights potential NO2 indoor sources basically linked to cooking activities, representing adverse health effects for population risk categories such as children or cooks. Considering that urban people spend a lot of their time in indoors, attention should be paid both to outdoor pollutant sources and to indoor source.