Potentially Toxic Metals and high resolution monitoring at regional and local scale of Persistent Organic Pollutants in the soil, air, and bulk deposition of the Campania Region, southern Italy: Sources and environmental processes

Campania Region, Southern Italy, in the last 10 years was facing potential environmental issues which needed to be addressed, with the proper scientific approach, to alleviate pressure from public opinion, based more on emotions than on scientific data. Such pressure indicated an increase of oncological incidence, not supported by scientific data on the presence of anomalous pollutants in different natural media (soil, water, air, agricultural products). To face environmental/health alarm, the Campania Regional Government in 2015 funded a large, multidisciplinary, environmental project known as Campania Trasparente, to Istituto Zooprofilattico del Mezzogiorno (IZSM), to get a deeper and scientific knowledge of the Campania territory carrying out geochemical investigations, to: 1) characterize the geochemical composition of agricultural soil, air and groundwater at regional and local scale; 2) define the level of bio-availability of the toxic elements; 3) try to demonstrate a direct relationship between the presence of contaminants in the environmental matrices, in agricultural products and finally in the human matrices (hair, urine, blood). Within this project we got data on the presence of the potentially toxic metals (PTMs) and hazardous persistent organic pollutants (POPs: OCPs, PCBs, PAHs, PAEs, PBDEs) in different media of the entire Region. The new large dataset complemented our research and monitoring activities, which before 2015, were focused mostly on PTMs in soils, both at regional and local scale. In Campania Trasparente project, samples (9,000) of top and bottom soils, air and bulk deposition (150 passive air samplers, over 7 seasons), waters (1,200), vegetation (2,500) and biological (4,200) media, were collected to characterize the status of PTMs and POPs. The results obtained showed that: a) most of these elements and compounds, in higher concentrations, occur predominantly in critical areas of Napoli Urban and Metropolitan Area (NMA) and in the Sarno river basin; b) the infamous area, in the Caserta and Napoli provincial territory, known as Terra dei Fuochi (Land of Fires), is only marginally interested by anomalous occurrence of PTMs and POPs in some spot areas, not justifying the emotional alarms calling for an increase of oncological cases due to diffuse illegal practice of wastes disposal in the area; c) the agricultural crops of the Terra dei Fuochi are not affected by anomalous PTM. Specifically, the ecological risk conditions for PAHs and some OCPs (Endosulfan) occur, mostly in NMA; PCBs are sourced mostly in urban areas, being dissipated in rural areas, whereas PAEs and PBDEs occur, in general, in concentrations similar to those in other Italian regions, with some higher hot spot values in NMA and south of Salerno town. The interactional complexity between metropolitan and the surrounding rural areas is also confirmed, as it is the role that urban areas play in the migration and transformation process of POPs. High urban-rural gradients for atmospheric PAHs, PCBs and OCPs are observed mostly in the NMA and the urban areas, identified as the main emission source of POPs.  Only OCPs, originating from the nearby agricultural areas, experienced long-term soil re-emission, continuously influencing conterminous urban environment via atmospheric transport processes.