Contaminants of emerging concern in water and sediment of the Venice Lagoon, Italy

This study investigates for the first time the contamination of water and sediment of the Venice Lagoon by twenty Contaminants of Emerging Concern (CECs): three hormones, six pharmaceutical compounds (diclofenac and five antibiotics, three of which are macrolides), nine pesticides (methiocarb, oxadiazon, metaflumizone, triallate, and five neonicotinoids), one antioxidant (BHT), and one UV filter (EHMC). Water and sediment samples were collected in seven sites in four seasons, with the aim of investigating the occurrence, distribution, and possible emission sources of the selected CECs in the studied transitional environment. The most frequently detected contaminants in water were neonicotinoid insecticides (with a frequency of quantification of single contaminants ranging from 73% to 92%), and EHMC (detected in the 77% of samples), followed by BHT (42%), diclofenac (39%), and clarithromycin (35%). In sediment the highest quantification frequencies were those of BHT (54%), estrogens (ranging from 35% to 65%), and azithromycin (46%). Although this baseline study does not highlight seasonal or spatial trends, results suggested that two of the major emission sources of CECs in the Venice Lagoon could be tributary rivers from its drainage basin and treated wastewater, due to the limited removal rates of some CECs in WWTPs. These preliminary results call for further investigations to better map priority emission sources and improve the understanding of CECs environmental behavior, with the final aim of drawing up a site-specific Watch List of CECs for the Venice Lagoon and support the design of more comprehensive monitoring plans in the future

Impacts of exhaust gas cleaning systems (EGCS) discharge waters on planktonic biological indicators

Exhaust Gas Cleaning Systems (EGCS), operating in open-loop mode, continuously release acidic effluents (scrubber waters) to marine waters. Furthermore, scrubber waters contain high concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and alkylated PAHs, potentially affecting the plankton in the receiving waters. Toxicity tests evidenced significant impairments in planktonic indicators after acute, early-life stage, and long-term exposures to scrubber water produced by a vessel operating with high sulphur fuel. Acute effects on bacterial bioluminescence (Aliivibrio fischeri), algal growth (Phaeodactylum tricornutum, Dunaliella tertiolecta), and copepod survival (Acartia tonsa) were evident at 10 % and 20 % scrubber water, while larval development in mussels (Mytilus galloprovincialis) showed a 50 % reduction at ∼5 % scrubber water. Conversely, larval development and reproductive success of A. tonsa were severely affected at scrubber water concentrations ≤1.1 %, indicating the risk of severe impacts on copepod populations which in turn may result in impairment of the whole food web

Bark and Grape Microbiome of Vitis vinifera: Influence of Geographic Patterns and Agronomic Management on Bacterial Diversity

In recent years, the concept of “microbial terroir” has been introduced in the frame of the more renowned notion of “vitivinicultural terroir,’ since several studies demonstrated that wine characteristics are related to regional microbial community compositions. Most of the existing research focused on grape berries microbiota, since it can directly impact wine quality. In this work we studied, for the first time through next-generation sequencing, the epiphytic bacterial community of vine bark and its relationships with grape microbiota. The study was carried out in two Italian wine appellations (situated in different regions) to explore the impact of biogeography, and the influence of two agronomical practices (biodynamic and conventional) was evaluated as well. Overall, our results show that grapevine bark harbors a rich epiphytic microbiota and displays a higher microbial biodiversity than grape berry. Moreover, this study suggests that geographic and anthropogenic factors impact both bark and grape bacteriomes, but to a different extent. The evidence of a “microbial terroir” seems to be even more marked in bark than in berries, possibly due to its permanence over time and to its physical proximity with soil. The importance of vine trunk bark, as potential source of inoculum for grapes and as interesting bacterial diversity habitat, is evidenced. This opens new fields of investigation, not only for researchers that aim at describing this little-known habitat within the vineyard, but also for stakeholders from the wine industry that want to understand the roles of microorganisms on the entire winemaking process, from vineyard to cellar

Search for tri-nucleon decays of Ge76 in GERDA

We search for tri-nucleon decays of $$^{76}$$Ge in the dataset from the GERmanium Detector Array (GERDA) experiment. Decays that populate excited levels of the daughter nucleus above the threshold for particle emission lead to disintegration and are not considered. The ppp-, ppn-, and pnn-decays lead to $$^{73}$$Cu, $$^{73}$$Zn, and $$^{73}$$Ga nuclei, respectively. These nuclei are unstable and eventually proceed by the beta decay of $$^{73}$$Ga to $$^{73}$$Ge (stable). We search for the $$^{73}$$Ga decay exploiting the fact that it dominantly populates the 66.7 keV $$^{73m}$$Ga state with half-life of 0.5 s. The nnn-decays of $$^{76}$$Ge that proceed via $$^{73m}$$Ge are also included in our analysis. We find no signal candidate and place a limit on the sum of the decay widths of the inclusive tri-nucleon decays that corresponds to a lower lifetime limit of 1.2$$\times$$10$$^{26}$$ yr  (90% credible interval). This result improves previous limits for tri-nucleon decays by one to three orders of magnitude

Searches for new physics below twice the electron mass with GERDA

A search for full energy depositions from bosonic keV-scale dark matter candidates of masses between 65 and 1021 keV has been performed with data collected during Phase II of the GERmanium Detector Array (Gerda) experiment. Our analysis includes direct dark matter absorption as well as dark Compton scattering. With a total exposure of 105.5 kg years, no evidence for a signal above the background has been observed. The resulting exclusion limits deduced with either Bayesian or Frequentist statistics are the most stringent direct constraints in the major part of the 140–1021 keV mass range. As an example, at a mass of 150 keV the dimensionless coupling of dark photons and axion-like particles to electrons has been constrained to α′/α1.5×1024 years and for a proton τp>1.3×1024 years at 90% CI. For the electron decay e-→νeγ a lower limit of τe>5.4×1025 years at 90% CI has been determined

Measurement of the 85Kr specific activity in the GERDA liquid argon

The radioactive isotope 85Kr is found in significant quantities in the atmosphere largely due to nuclear industry. Its β -decay with a half-life of 10.7 years and a Q-value of 687 keV is a dangerous background source for low-threshold noble gas and liquid detectors, which distill their detector medium from air. The Gerda experiment was operating high-purity germanium detectors immersed in a clean liquid argon bath deep underground to search for neutrinoless double beta decay with unprecedented sensitivity. The 85Kr specific activity in the liquid argon at the start of the second phase of the experiment has been determined to be mBq/kg through an analysis of the full subsequent data set that exploits the excellent γ -ray spectroscopic capabilities of Gerda

Search for the in-situ production of ⁷⁷Ge in the GERDA neutrinoless double-beta decay experiment

The beta decay of 77Ge and 77mGe, both produced by neutron capture on 76Ge, is a potential background for Germanium based neutrinoless double-beta decay search experiments such as GERDA or the LEGEND experiment. In this work we present a search for 77Ge decays in the full GERDA Phase II data set. A delayed coincidence method was employed to identify the decay of 77Ge via the isomeric state of 77As (9/2+, 475 keV, T1/2 = 114µs, 77mAs). New digital signal processing methods were employed to select and analyze pile-up signals. No signal was observed, and an upper limit on the production rate of 77Ge was set at < 0.216 nuc/(kg· yr) (90% CL). This corresponds to a total production rate of 77Ge and 77mGe of < 0.38 nuc/(kg· yr) (90% CL), assuming equal production rates. A previous Monte Carlo study predicted a value for in-situ 77Ge and 77mGe production of (0.21 ± 0.07) nuc/(kg.yr), a prediction that is now further corroborated by our experimental limit. Moreover, tagging the isomeric state of 77mAs can be utilised to further suppress the 77Ge background. Considering the similar experimental configurations of LEGEND-1000 and GERDA, the cosmogenic background in LEGEND-1000 at LNGS is estimated to remain at a sub-dominant level

Search for the in-situ production of 77^{77}Ge in the GERDA neutrinoless double-beta decay experiment

The beta decay of $^{77}$Ge and $^{77m}$Ge, both produced by neutron capture on $^{76}$Ge, is a potential background for Germanium based neutrinoless double-beta decay search experiments such as GERDA or the LEGEND experiment. In this work we present a search for $^{77}$Ge decays in the full GERDA Phase II data set. A delayed coincidence method was employed to identify the decay of $^{77}$Ge via the isomeric state of $^{77}$As (9/2$^{+}$, 475 keV, T$_{1/2}$ = 114 μs, $^{77m}$As). New digital signal processing methods were employed to select and analyze pile-up signals. No signal was observed, and an upper limit on the production rate of $^{77}$Ge was set at < 0.216 nuc/(kg $\cdot$ yr) (90% CL). This corresponds to a total production rate of $^{77}$Ge and $^{77m}$Ge of < 0.38 nuc/(kg $\cdot$ yr) (90% CL), assuming equal production rates. A previous Monte Carlo study predicted a value for in-situ $^{77}$Ge and $^{77m}$Ge production of (0.21 ± 0.07) nuc/(kg $\cdot$ yr), a prediction that is now further corroborated by our experimental limit. Moreover, tagging the isomeric state of $^{77m}$As can be utilised to further suppress the $^{77}$Ge background. Considering the similar experimental configurations of LEGEND-1000 and GERDA, the cosmogenic background in LEGEND-1000 at LNGS is estimated to remain at a sub-dominant level

Final Results of GERDA on the Two-Neutrino Double-β Decay Half-Life of 76Ge

We present the measurement of the two-neutrino double- β decay rate of 76 Ge performed with the GERDA Phase II experiment. With a subset of the entire GERDA exposure, 11.8 kg yr, the half-life of the process has been determined: T 2 ν 1 / 2 = ( 2.022 ± 0.01 8 stat ± 0.03 8 syst ) × 10 21     yr . This is the most precise determination of the 76 Ge two-neutrino double- β decay half-life and one of the most precise measurements of a double- β decay process. The relevant nuclear matrix element can be extracted: M 2 ν eff = ( 0.101 ± 0.001 )