A step forward on site-specific environmental risk assessment and insight into the main influencing factors of CECs removal from wastewater.

The presence of Contaminants of Emerging Concern (CECs) in water systems has been recognized as a potential source of risk for human health and the ecosystem. The present paper aims at evaluating the effects of different characteristics of full-scale Wastewater Treatment Plants (WWTPs) on the removal of 14 selected CECs belonging to the classes of caffeine, illicit drugs and pharmaceuticals. Particularly, the investigated plants differed because of the treatment lay-out, the type of biological process, the value of the operating parameters, the fate of the treated effluent (i.e. release into surface water or reuse), and the treatment capacity. The activity consisted of measuring concentrations of the selected CECs and also traditional water quality parameters (i.e. COD, phosphorous, nitrogen species and TSS) in the influent and effluent of 8 plants. The study highlights that biodegradable CECs (cocaine, methamphetamine, amphetamine, benzoylecgonine, 11-nor-9carboxy-Δ9-THC, lincomycin, trimethoprim, sulfamethoxazole, sulfadiazine, sulfadimethoxine, carbamazepine, ketoprofen, warfarin and caffeine) were well removed by all the WWTPs, with the best performance achieved by the MBR for antibiotics. Carbamazepine was removed at the lowest extent by all the WWTPs. The environmental risk assessed by using the site-specific value of the dilution factor resulted to be high in 3 out of 8 WWTPs for carbamazepine and less frequently for caffeine. However, the risk was reduced when the dilution factor was assumed equal to the default value of 10 as proposed by EU guidelines. Therefore, a specific determination of this factor is needed taking into account the hydraulic characteristics of the receiving water body.

Valorisation of residues from municipal wastewater sieving through anaerobic (co-)digestion with biological sludge.

The Circular and Green Economy principles is inspiring new approaches to municipal wastewater treatment plants (MWWTPs) design and operation. Recently, an ever-growing interest is devoted to exploring the alternatives for switching the WWTPs from being able to 'simply' removing contaminants from water to biorefinery-like plants where energy and material can be recovered. In this perspective, both wastewater and residues from process can be valorised for recovering nutrients (N and P), producing value added products (i.e. biopolymers), energy vectors and biofuels (i.e. bio-H2, bio-CH4 and bioethanol). As an additional benefit, changing the approach for WWTPs design and operation will decrease the overall amount of landfilled residues. In this context, the present research is aimed at evaluating the CH4 production potential of MWW screening units' residues. While such a stream is typically landfilled, the expected progressive increase of biodegradable matter content due to the ban on single-use plastic along with the boost of bioplastics makes the investigation of different biochemical valorisation routes more and more interesting from an environmental and economical perspective. Thus, a full-scale data collection campaign was performed to gain information on screening residues amount and properties and to analyse the relationship with influent flowrate. The most relevant residue properties were measured, and lab-scale tests were carried out to evaluate the bio-CH4 potential.

Impact of COVID19 restrictions on organic micropollutants in wastewater treatment plants and human consumption rates.

COVID19 pandemic and the consequent restrictions to constrain SARS-CoV-2 spreading produced several impacts on the worldwide population. The present study focused on 10 Organic Micropollutants (illicit drugs, pharmaceuticals including some antibiotics and caffeine) and aimed to assess: (1) if COVID19 pandemic restrictions affected the load of those contaminants released into the sewage network and consequently the removal achieved by the Wastewater Treatment Plants; (2) if pursuant to the COVID19 pandemic, there was a change in population consumption rates of the same compounds through the wastewater-based epidemiology (WBE) approach. Two full-scale wastewater treatment plants (WWTPs) located in Central Italy were chosen as case studies, which are distinguished by different characteristics of the catchment area and water treatment layouts. The study was based on a 2-years monitoring activity of the concentration of the above organic micropollutants, traditional water quality parameters (COD, TSS, nitrogen compounds, total phosphorous) and flow rate in the influent and effluent. The statistical analysis of the monitoring data showed an increase of the influent load of most of the organic micropollutants. A decrease from 22% to -18% of the median removal efficiency was observed for carbamazepine in the WWTP with the lower treatment capacity only. The other compounds were removed roughly at the same rate. The application of the WBE approach demonstrated an increase in the consumption rate of cocaine, trimethoprim, sulfamethoxazole, sulfadiazine, carbamazepine and above all caffeine during the COVID19 restrictions period. These results highlight that COVID19 pandemic affected people's lifestyle and habits also as far as drugs consumption is concerned, which in turn might have an impact on the treatment efficacy of plants and finally on the receiving water body quality. Therefore, it is mandatory to keep monitoring to improve knowledge and eventually to implement the required measures to address this new problem.

A laboratory-study on the analytical determination and removal processes of THC-COOH and bezoylecgonine in the activated sludge reactor.

The present study focused on 11-nor-9carboxy-Δ9-THC (THC-COOH) and Benzoylecgonine (BE), the most common metabolites of cannabis and cocaine, respectively, present in the domestic sewage entering the wastewater treatment plants. The aims of the study were: (1) to validate the analytical method of detection in wastewater and sludge; (2) to determine contribution of biodegradation and other processes to the removal in the biological reactor of the wastewater treatment plant (WWTP) and the response of biomass to different drug concentrations. The Ultra-Performance Liquid Chromatography coupled to tandem Mass Spectrometry method showed to be repeatable and reliable (recovery>75%; repeatability<10-15%; bias uncertainty<10) for measurements in wastewater; the ultrasound assisted extraction (USE) demonstrated to be reliable as pre-treatment of activated sludge solid phase. Both drugs were fully removed from the liquid phase in the lab-scale biological reactor within 24 h. Biodegradation was the main BE removal mechanism, and the first order kinetic model provided the best fitting of the experimental data. THC-COOH was mainly removed due to a combination of adsorption and biodegradation; adsorption was better described by the pseudo-second order kinetic model and the Freundlich isotherm. Both drugs at the higher concentrations caused inhibition of nitrogen oxidation and carbon removal.

A study through batch tests on the analytical determination and the fate and removal of methamphetamine in the biological treatment of domestic wastewater.

Methamphetamine (MET) is one of the most used illicit drugs in Europe and is recognized as one of the Emerging Organic Micropollutants. It is discharged into the sewerage system from different sources and then enters the wastewater treatment plants. The present study aimed at providing a better knowledge of the fate of MET through the wastewater treatment plants. The study addressed two different issues: (1) optimization of the analytical methods for MET determination in both liquid and sludge phases, focusing on the effects of potentially interfering substances and (2) investigation on the behaviour of MET in the biological treatment process, with specific concern for the biomass activity at different drug concentrations. Results of the study on issue 1 highlighted that the applied analytical method for MET determination (UPLC-MS/MS) is affected by the main components of wastewater for about 9-23%, which is comparable with the uncertainties of the method (about ± 28%). The method showed also to be repeatable and reliable (recovery > 75%; repeatability < 10-15%; bias uncertainty < 30%), and relatively easy-to-use. Therefore, it can be considered suitable for measurements on routine base in the WWTPs. Batch tests conducted to address issue 2 showed total removal of 84, 90, and 96% at 50, 100, and 200 ng/L initial MET concentration, respectively, for a contact time of 6 h. The removal process was mainly ascribed to the biological activity of both heterotrophic and autotrophic bacteria. The pseudo first-order kinetic model provided the best fitting of the experimental data of the overall biological processes at all the tested concentrations. Furthermore, the respirometric tests showed that MET does not induce any inhibition. Adsorption of MET on activated sludge was always very low.

Varanoid Tooth Eruption and Implantation Modes in a Late Cretaceous Mosasaur.

Erupting teeth are some of the oldest witnesses of developmental processes in the vertebrate fossil record and provide an important resource for vertebrate cladistics. Here, we have examined a mosasaur jaw fragment from central Texas using ultrathin ground section histology and 3D tomographic imaging to assess features critical for the cladistic placement of mosasaurs among varanoids vs. snakes: (i) the orientation of replacement teeth compared to the major tooth axis, (ii) the occurrence of resorption pits, and (iii) the mode of tooth implantation/attachment to the tooth bearing element (TBE). The replacement tooth studied here developed in an inclined position slightly distal of the deciduous parent tooth, similar to another varanoid squamate, the Gila monster Heloderma suspectum. Ground sections and tomographs also demonstrated that the replacement tooth attachment apparatus was entirely intact and that there was no evidence of mechanical deformation. Sections and tomographs further illustrated that the replacement tooth was located within a bony crypt and the inclination of the crypt matched the inclination of the replacement tooth. These preparations also revealed the presence of a resorption pit within the boundaries of the deciduous tooth that surrounded the developing replacement tooth. This finding suggests that developing mosasaur teeth developed within the walls of resorption pits similar to varanoid tooth germs and unlike developing snake teeth which are surrounded by fibrous connective tissue integuments. Finally, mosasaurs featured pseudo-thecodont tooth implantation with teeth anchored within a socket of mineralized tissue by means of a mineralized periodontal ligament. Together, these data indicate that the moderate inclination of the erupting mosasaur tooth studied here is neither a result of postmortem displacement nor a character representative of snakes, but rather a shared character between Mosasaurs and other varanoids such as Heloderma. In conjunction with the presence of resorption pits and the evidence for pseudothecodont tooth implantation, the tooth eruption and implantation characters described in the present study either place mosasaurs among the varanoids or suggest convergent evolution mechanisms between both clades, with mosasaurs evolving somewhat independently from a common varanoid ancestor.

[Virus removal in conventional wastewater treatment process]. / Rimozione dei virus nei processi convenzionali di trattamento delle acque reflue.

Little has been published in the scientific literature on the distribution of pathogenic viruses and on their removal in the different treatment phases in wastewater treatment plants in Italy. Recent advances in molecular biology have reduced analytic costs and allowed the detection of virus directly in the environment. This study evaluates the presence of enteric viruses and their removal in three treatment plants of different sizes and which use different treatment methods. Overall 92 samples were collected during three seasonal campaigns (winter, spring-summer, and autumn). Samples were collected at different phases of the treatment process. Chemical and microbiological analyses were performed. Samples were concentrated by ultrafiltration and tested for the presence of hepatitis A virus, adenovirus, rotavirus, astrovirus, norovirus and enteroviruses. All viruses, excluding the Enteroviruses were detected through biomolecular testing. Enteroviruses, were isolated on BGM cells and subsequently genotyped at the VP1 region. Sixty-two of the 92 samples tested positive for viruses; of these, 21 tested positive for HAV, 4 for adenovirus, 9 for rotavirus, 21 for astrovirus, and 7 for norovirus. Enteroviruses were present on average in 44% of samples collected during the three sampling campaigns. Hepatitis A virus was isolated during the spring-summer period while Astroviruses were identified in all three sampling campaigns. Different enteroviruses were isolated, including four types of Coxsackie B virus variably isolated in all three campaigns, and type 1 Echovirus isolated in the second and third campaigns. All detected polioviruses were of the vaccine-type and were identified as types 1 and 3. Both viral genotypes of Norovirus were identified. Adenoviruses were only sporadically isolated and rotaviruses were identified as type A. As expected, results show a greater prevalence of Enteroviruses and this reflects viral circulation in the population. Regarding the efficacy of the different treatment stages, primary treatment was found to remove only small percentages of viruses, while activated sludge e subsequent sedimentation were found to be more effective.