• Hardy Hartmann posted an update 6 months, 1 week ago

    Wastewater-based monitoring of the spread of the new SARS-CoV-2 virus, also referred to as wastewater-based epidemiology (WBE), has been suggested as a tool to support epidemiology. An extensive sampling campaign, including nine municipal wastewater treatment plants, has been conducted in different cities of the Federal State of North Rhine-Westphalia (Germany) on the same day in April 2020, close to the first peak of the corona crisis. Samples were processed and analysed for a set of SARS-CoV-2-specific genes, as well as pan-genotypic gene sequences also covering other coronavirus types, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Additionally, a comprehensive set of chemical reference parameters and bioindicators was analysed to characterize the wastewater quality and composition. Results of the RT-qPCR based gene analysis indicate the presence of SARS-CoV-2 genetic traces in different raw wastewaters. Furthermore, selected samples have been sequenced using Sanger technology to confirm the specificity of the RT-qPCR and the origin of the coronavirus. A comparison of the particle-bound and the dissolved portion of SARS-CoV-2 virus genes shows that quantifications must not neglect the solid-phase reservoir. The infectivity of the raw wastewater has also been assessed by viral outgrowth assay with a potential SARS-CoV-2 host cell line in vitro, which were not infected when exposed to the samples. This first evidence suggests that wastewater might be no major route for transmission to humans. Our findings draw attention to the need for further methodological and molecular assay validation for enveloped viruses in wastewater.Human coronaviruses are RNA viruses that are sensitive to ultraviolet (UV) radiation. Sunlight contains UVA (320-400 nm), UVB (260-320 nm) and UVC (200-260 nm) action spectra. UVC can inactivate coronaviruses, including severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). The incidence and mortality of coronavirus disease 2019 (COVID-19) are considered to be correlated with vitamin D levels. Vitamin D synthesis in human skin is closely related to exposure to UVB radiation. Therefore, the incidence and mortality of COVID-19 are also considered to be correlated with Vitamin D levels. In this study, Spearman and Kendall rank correlation analysis tests were used to analyze the correlation between the average percent positive of five human coronaviruses (SARS-CoV-2, CoVHKU1, CoVNL63, CoVOC43, and CoV229E) in the U.S. and the corresponding sunlight UV radiation dose The results indicated that the monthly average percent positive of four common coronaviruses was significantly negatively correlated with the sunlight UV radiation dose. The weekly percent positive of SARS-CoV-2 during April 17, 2020 to July 10, 2020 showed a significant negative correlation with the sunlight UV radiation dose in census regions 1 and 2 of the U.S. while no statistical significance in the other regions. Additionally, sunlight UV radiation also showed some negative effects with respect to the early SARS-CoV-2 transmission.Health care facilities can represent point sources for pharmaceutical residues in public sewer systems. selleck chemicals llc Compared to general hospitals, more specialized health care facilities might also have a different pattern of medication. Therefore, the on-site treatment of wastewater from such facilities could be an effective strategy to reduce emissions into water bodies and was the aim of this study. Wastewater from three health care facilities (nursing home, clinic with orthopaedic focus, and psychiatric clinic) was treated in lab-scale and semi-industrial trials. Biological treatment was performed via an ultrafiltration membrane bioreactor (UF-MBR), after which adsorption onto granular activated carbon (using rapid-small-scale column tests GAC-RSSCT), ozonation and a UV/H2O2 advanced oxidation process (AOP) were tested and compared. The removal of 17 pharmaceutical compounds and drug metabolites from 9 drug classes (e.g. analgesics, antibiotics, anticonvulsants) was evaluated. Most of the measured OMP were detected with concentrations between 1,000 and 30,000 ng L-1 in the influent of the MBR. The UF-MBR provided an effective mechanical-biological cleaning of the wastewater, with micropollutant removal efficiencies between 0 and > 95%, making further treatment necessary to remove the micropollutants. Each combination of the UF-MBR with one of the three further treatments achieved removal efficiencies above 80% for most of the investigated substances, reducing many to below the quantification limit of 10 ng L-1. The results show the general suitability of combining the UF-MBR with either GAC-adsorption, ozonation or AOP for eliminating pharmaceutical residues. However, the AOP process has a significantly higher energy demand than the other two processes. Moreover, specific settings and dosages depend on the respective wastewater matrix.Nitrous oxide (N2O) emissions from anammox-based processes are well documented but insight into source of the N2O emission in high-rate anammox granular sludge reactors (AGSR) is limited. In this study, metagenomics and fed-batch experiments were applied to investigate the relative contributions of anammox granules and flocs to N2O production in a high-rate AGSR. Flocs, which constitute only ~10% of total biomass contributed about 60% of the total N2O production. Granules, the main contributor of nitrogen removal (~95%), were responsible for the remaining ~40% of N2O production. This result is inconsistent with reads-based analysis that found the gene encoding clade II type nitrous oxide reductase (nosZII) had similar abundances in both granules and flocs. Another notable trend observed was the relatively higher abundance of the gene for NO-producing nitrite reductase (nir) in comparison to the gene for the nitric oxide reductase gene (nor) in both granules and flocs, indicating nitric oxide (NO) may accumulate in the AGSR. This is significant since NO and N2O pulse assays demonstrated that NO could lead to N2O production from both granules and flocs. However, since anammox bacteria, which were shown to be in higher abundance in granules than in flocs, have the capacity to scavenge NO this provides a mechanism by which its inhibitory effects can be mitigated, limiting N2O release from the granules, consistent with experimental observation. These results demonstrate flocs are the main source of N2O emission in AGSR and provide lab-scale evidence that NO-dependent anammox can mitigate N2O emission.

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