Emissions of pharmaceuticals and plant protection products to the lagoon of Venice: development of a new emission inventory.

Estimating the emissions of chemical pollutants to water is a fundamental step for the development and application of effective and sustainable management strategies of water resources, but methods applied so far to build chemicals inventories at the European or national scale show several limitations when applied at the local scale. The issue is particularly relevant when considering contaminants of emerging concern (CECs), whose environmental releases and occurrence are still poorly studied and understood. In this work, an approach to estimate water emissions of nine active pharmaceutical ingredients (APIs) and ten most applied plant protection products (PPPs) is presented, considering proxy indicators (e.g., sales data and census information). The application area is the lagoon of Venice (Italy), a complex transitional environment highly influenced by anthropic pressures (e.g., agricultural and industrial activities, animal breeding, and wastewater discharge). The presented approach can be tailored to the information available for any local scale case study. Data on annual regional sales of PPPs and APIs were integrated with georeferenced demographic and economic statistics (such as census and land-use information) to estimate chemicals emissions to surface water and groundwater. A sensitivity and uncertainty analysis identified the main factors affecting emissions estimates, and those contributing more significantly to results uncertainty. Results showed the highest estimated emissions of APIs for antibiotics (i.e., amoxicillin, clarithromycin, azithromycin, and ciprofloxacin) used for humans and animals, while most of hormones' emission (i.e., 17- α-ethinylestradiol and 17-ß-estradiol) derived from animal breeding. Regarding PPPs, glyphosate and imidacloprid emissions were one to two orders of magnitude higher compared to the other chemicals. Uncertainty and sensitivity analysis showed that the variability of each parameter used to estimate emissions depends greatly both on the target chemical and the specific emission source considered. Excretion rates and removal during wastewater treatment were major key parameters for all the target pharmaceutical compounds, while for PPPs the key parameter was their loss into the natural waters after application.

Groundwater contamination by fluorinated aromatics: Benzotrifluoride and its derivatives.

Benzotrifluoride (BTF) and its derivatives (BTFs) were found in the groundwater of the Veneto region (Italy) as a result of industrial contamination dating back to the 1970s. In the first survey, BTF and 6 BTFs were identified, out of which 4-chloro-3nitrobenzotrifluoride (3N4CBTF) was the only quantified analyte (concentration up to 1 mg L-1) and was used to trace the contamination plume. A survey carried out in 2008-2009 after the development of more suitable analytical procedures based on GC-MS, allowed to determine 4 new derivatives in addition to BTF and BTFs previously identified, with the most abundant compounds found at concentrations up to 11.9 µg L-1 and 7.2 µg L-1 respectively. A systematic monitoring program for the evaluation of persistence and distribution of fluorinated compounds was carried out in 2013-2018, and new data about the BTF and BTFs occurrence and distribution were gathered. Additional BTFs were identified and high concentrations of individual BTFs were recorded near the contamination source (e.g. 20.3 µg L-1 of 4-chloro-3-nitrobenzotrifluoride in 2017) as well as at large distance (e.g. 22.4 µg L-1 of 3N4CBTF and 12.5 µg L-1 of 4-chlorobenzotrifluoride in 2018). The results of BTFs monitoring campaigns carried out in 2008-2009 and 2017-2018 are compared and related to the historical data to assess the overall occurrence and distribution of BTFs contamination over a time range of ∼40 years. Remarkably, BTFs were still found (2018) at µg L-1 range. Spatial and temporal occurrence of BTF and BTFs in groundwater has been assessed for the first time.