Data on occurrence and fate of emerging contaminants in a urbanised area.

These data and analyses support the research article "Mass balance of emerging contaminants in the water cycle of an highly urbanized and industrialized area of Italy" by Castiglioni et al. (2018) [1]. The occurrence of 80 emerging contaminats in waste and surface water was investigated in an highly urbanised area of Italy, the River Lambro basin. The data presented here include: (1) concentrations in untreated and treated wastewater of different wastewater treatment plants (WWTPs); (2) concentrations in surface water collected along the river Lambro, in the north and south of the city of Milan (main urban center in the area). These concentrations indicate the distribution and fate of emerging contaminats in the environment.

Mass balance of emerging contaminants in the water cycle of a highly urbanized and industrialized area of Italy.

The occurrence of several classes of emerging contaminants (ECs) was assessed in the River Lambro basin, one of the most urbanized and industrialized areas of Italy. The study aims were to identify the main sources of ECs, quantify their amounts circulating in the water cycle, and study their fate in the aquatic environment. More than 80 ECs were selected among pharmaceuticals (PHARM), personal care products (PCPs), disinfectants (DIS), illicit drugs (IDs), perfluorinated compounds (PERF), alkylphenols and bisphenol A (Alk-BPA), and anthropogenic markers (AM). Specific analytical methods were developed for quantitative analysis based on solid phase extraction and liquid chromatography tandem mass spectrometry. ECs were measured in rivers upstream and downstream of the main city (Milan), and in untreated and treated wastewater from Milan to assess the contribution to river contamination, and in superficial and deep groundwater in the city area to study the relationship between river and groundwater contamination. Samples were collected in a two-year monitoring campaign. Almost all ECs were ubiquitous in untreated wastewater, at concentrations up to the µg/L range, and the most abundant classes were PHARM and AM. Removals during different wastewater treatment processes were studied and the most stable substances were PHARM, PCPs and PERF. The mass loads increased for all the classes of ECs along the River Lambro basin. A mass balance was done in the river basin and allowed to identify the main sources of contamination, which were domestic, from treated or untreated wastewater, for PHARM, PCPs and IDs, mainly industrial for PERF, and both industrial and domestic for Alk-BPA. The study of AM helped to identify direct discharges of untreated wastewater. A substantial contribution of surface water to groundwater contamination was observed. This study improves the knowledge on occurrence, sources and fate of multiple classes of ECs in a highly urbanized area providing useful information to help the establishment of EU regulations for ECs.

Persistent organic pollutants in boreal and montane soil profiles: distribution, evidence of processes and implications for global cycling.

The distribution of persistent organic pollutants (POPs) within background soil profiles was investigated in boreal (Norway) and montane (Italy) areas. The typical build-up of slowly mineralizing humus layers, containing high amounts of soil organic matter (SOM) makes soils of such ecosystems an important global sink for POPs released to the environment. The study focused on evidence and implications of processes influencing the fate of POPs in soil. POP deposition, interaction with SOM, volatilization, leaching, degradation, and bioturbation are discussed. Results indicate that the less volatile POPs such as hexa- and higher chlorinated biphenyls (CBs) or polybrominated diphenyl ethers are very stable in soil profiles, undergoing little translocation or (re)transfer to other environmental compartments. In contrast, more volatile compounds (e.g., tri- and tetra-CBs) were found in soil layers below those formed from vegetation ever directly exposed to airborne POPs. This suggests the occurrence of downward transport and hence limited surface-air exchange of more volatile POPs as they are removed from the top layers. Such soils may therefore be able to retain higher amounts of these compounds than just addressed by the capacity of their surface layers.

Accumulation parameters and seasonal trends for PCBs in temperate and boreal forest plant species.

The concentration of polychlorinated biphenyls (PCBs) in the air and vegetation was measured periodically in two alpine forests, during the growing season. Foliage samples from nine plant species typical of the temperate and boreal environment were collected and analyzed. Leaf concentrations of tri- and tetra-CBs showed fast response times with changing temperature and gas-phase concentrations, suggesting that a partitioning equilibrium is approached relatively rapidly (few days) in the field. Heavier compounds showed kinetically limited accumulation trends, not reaching equilibrium during the growing season. Results were used to estimate the bioconcentration factors or equilibrium plant/air partition coefficient (KPA) for each species. Values of log KPA (calculated on a mass/volume basis) ranged between 0.78 and 1.96 and were correlated to the log KOA. Uptake trends of the higher chlorinated compounds showed intraspecific differences which were partially explained by the specific leaf area (SLA).