Assessing the influence of local sources on POPs in atmospheric depositions and sediments near Trento (Italy)

- We analyzed POPs in wet and dry depositions and pond sediments.
- We tried to identify different sources of emission and exposure levels.
- POPs are more abundant in winter than in summer depositions.
- The seasonal trend of PAHs is consistent with precipitation and domestic heating.
- Sediments show a peak in concentration at mid-level, then decrease.

The content of five classes of Persistent Organic Pollutants (POPs) in the atmospheric depositions and sediments of an area interested by a steelmaking plant, a state highway and urban settlements were investigated. Samples were collected through a wet and dry sampler onto the roof of a primary school or core drilled from the sediments of a nearby pond and analyzed for PCDD/Fs, PCBs, PAHs, PBDEs and PCNs in order to assess the role of different sources on direct emissions in atmosphere and transfer to other environmental compartments. The method was tested with reference materials, laboratory and field blanks. The results show higher fluxes of POPs in winter depositions, with PAH levels up to 6500 ng m−2 d−1. Patterns and diagnostic ratios suggest that the main sources are fuel and wood combustion. PCDD/Fs are present at background level, with maximum total fluxes of 17 pg m−2 d−1 in depositions and concentrations of 7 pg g−1 in sediments. All concentrations peak at mid-level in the sediment core and then decrease towards surface, as an effect of regulatory limitations and update to modern industrial technologies.