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Abstract Efficacy of vermi-transformation for metal partitioning and transformation from Upflow Anaerobic Sludge Blanket (UASB) and Activated Sludge (AS) was investigated. Sludge samples were mixed with cow dung (CD) in two combinations (1:1 (UASB/AS:CD)) & (2:1(UASB/AS: CD)). Fractionation study revealed that Zn, Cd & Pb were associated with reducible fractions, and Cr, Cu with oxidizable fractions. Higher removal efficiency for 1:1 (UASB/AS: CD) combination over 2:1 (UASB/AS: CD) implies the non-significant contribution of cow dung during the metal stabilization process. After vermi-remediation, maximum metal removal was achieved at 1:1 ratio than 2:1 in AS. In UASB, 1:1 ratio worked better for Cr, Zn & Cd, whereas for Cu & Zn 2:1 ratio resulted in efficient removal. Overall for both AS and UASB, efficiency was found to be higher in 1:1 treatment ratio. The value of K d (Bio sorption) was highest in Cu followed by Cr, which indicates the closer association with the metal bound organic matter (R2 ≥ 0.99). Based on the compliance study between two estimated sorption coefficients K d (Biosorption & Fractions), vermi-remediation was found to be effective for AS than UASB. Therefore, the obtained results clearly validate the feasibility of integration of vermi-remediation as a potential promising ecological techniques for removing metal contaminant from the wastewater. Further research is required to study the decontamination of emerging contaminants with such integrated technology, which have physico-chemical properties different than metal ions. Graphical abstract (a) Stages of experiment (b) Conceptual model of metal bioaccumulation by Earthworm (Eisenia fetida). Image 1 Highlights • Prominent efficacy of vermitechnology integration with wastewater treatment plant. • Significant compliance between K d estimated through biosorption and fractionations. • Vermitechnology found to be more efficient with activated sludge (AS) than UASB. • 1:1(Sample:Cowdung) mixing ratio showed higher metal stabilization than 2:1(S:CD). [ABSTRACT FROM AUTHOR]

Highly compressible sewage sludge (SS) derived geopolymer was magnetized with impregnation of magnetite (Fe 3 O 4) nanoparticles (NPs), and these newly developed and characterized adsorbents were tested in a batch mode for the sorptive removal of metalloid arsenic (As) from a significant potable water resource (groundwater). Various sorption experiments were performed under variable pH (4.0–9.0), magnetized geopolymer dosages (0.1–3 g L−1), contact time (0–180 min), initial As concentrations (10–100 μg L−1) and co–existing anions to develop a critical understanding of the optimal experimental requirements and to assess the sorption kinetics and isotherms. Magnetized geopolymer had better monolayer sorption capacity (∼51.6 μg g−1, after 3 h) for As(V) than only geopolymer (∼9.81 μg g−1, after 3 h) at near neutral pH (∼6.0). The sorption process onto magnetized geopolymer was facilitated by intraparticle diffusion as well as surface complexation mechanisms and was best explained by the pseudo second order kinetic model (R2 ≥ 0.95) and Freundlich and Temkin isotherm models (R2 ≥ 0.90). The exhausted composite adsorbent was sufficiently regenerated up to five sorption–desorption–regeneration cycles using 0.1 M NaOH. Further, it also displayed an excellent As(V) removal capacity from the cocktail mixture of the common geogenic anions and their antagonistic effect follows the order of: NO 3 − < Cl− < SO 4 2− < F− < PO 4 3−. The proposed waste derived sustainable composite material was proved to be a promising sorbent for economic As(V) removal under simulated complex environmental conditions. [Display omitted] • Sewage sludge can be utilized for synthesizing geopolymer. • Maximum sorption by magnetized geopolymer occurred at near neutral pH (∼6). • Adsorption of As(V) followed Freundlich (R2 ≥ 0.98) isotherm model. • Pseudo–second–order (R2 ≥ 0.95) model revealed chemisorption kinetics for As(V). • 0.1 M NaOH was found as a potential desorbing agent up to five regeneration cycles. [ABSTRACT FROM AUTHOR]

Sewage sludge (SS) management has been regarded as a serious environmental and health issue around the globe, especially in developing countries like India, mainly due to the lack of proper regulatory criteria, and appropriate engineering infrastructures. The present research work demonstrates the utilization of Fly Ash (FA) in varying percentages (with an interval of 10%) with SS as brick for sustainable building material with special emphasis on dimensional Effect. The impact of dimensional effect is measured using compressive strength behaviour for a stress rate of 14 MPa/min of two different sizes of brick i.e. D1 and D2 of sizes 7 × 7x7 cm3 and 2 × 2x2 cm3, respectively. Owing to the sintering effect, the maximum strengths of 4.02 MPa and 7.6 MPa are noticed for a composition of 60% SS+40% FA for D1 and 40% SS + 60% FA for D2, respectively. According to the Indian Standards (IS) 13757: 1993, an exhibited strength of more than 3.5 MPa by any brick composition enables it to be used as a common building brick. In general, due to the formation of triangular wedges, the D2 bricks exhibited better strength for any mixing ratio of FA and SS. The added benefit in our study was lower thermal conductivity (0.48 Wm−1K−1) of the prepared fired brick implying its better insulation property. Our study uniquely highlights the possible utilization of FA for stabilizing SS for sustainable substitution of natural clay fired brick. Future study may further investigate the compositional effect of FA on the thermal and thermodynamic attributes of the bricks. Image 1 • Pioneer study on bricks that visualizes dimensional effect along with mechanical properties. • 40–60% fly ash with sewage sludge satisfies Indian codal provisions as construction material. • Thermal conductivity of synthesized brick is lower than conventional fired clay bricks. • Dimensional effect significantly influences the compressive strength behaviour. [ABSTRACT FROM AUTHOR]

In order to benefit the public, community workers and scientific community, we hereby present a chronicle of SARS-CoV-2 that leads to the unseen precedent of social distancing and lockdown owing to coronavirus disease (COVID-19). Information on this life-threatening pandemic of COVID-19 is sparse and discrete; and the urgency is such that the dissemination of information is increasing with numerous daily publications on the topic. Therefore, we developed a comprehensive review on various aspects of SARS-CoV-2 and COVID-19. We scientifically compiled published research, news, and reports from various sources to comprehend and summarize the information and findings on Coronaviruses. The review explicitly covers the aspects like genome and pedigree of SARS-CoV-2; epidemiology, prognosis, pathogenesis, symptoms and diagnosis of COVID-19 in order to catalog the right information on transmission route, and influence of environmental factors on virus transmissions, for the robust understanding of right strategical steps for proper COVID-19 management. We have explicitly highlighted several useful information and facts like: i) No established relationship between progression of SARS-CoV-2 with temperature, humidity and/or both, ii) The underlying mechanism of SARS-CoV-2 is not fully understood, iii) Respiratory droplet size determines drop and airborne-based transmission, iv) Prognosis of COVID-19 can be done by its effects on various body organs, v) Infection can be stopped by restricting the binding of S protein and AE2, vi) Hydroxychloroquine is believed to be better than chloroquine for COVID-19, vii) Ivermectin with Vero-hSLAM cells is able to reduce infection by ~5000 time within 2 days, and viii) Nafamostat mesylate can inhibit SARS-CoV-2 S protein-initiated membrane fusion. We have also suggested future research perspectives, challenges and scope. Unlabelled Image • Phylogeny of the SARS-CoV-2 is remarkably similar to SARS of pangolin and/or bat origin. • Transmission depends on respiratory droplet size, environmental condition and immunity. • COVID-19 progression is highly debated for temperature, humidity, and lifestyle dependence. • Infection can be restricted through restricting binding of S protein and AE2. • Increasing neutrophil and lymphocyte ratio (NLR) may give early sign of COVID-19. [ABSTRACT FROM AUTHOR]

An evaluation of the seasonal dynamics of metal (Cd, Cr, Cu, Pb and Zn) phase distribution and speciation, along with different hydrogeochemical facies, was conducted along the entire stretch of a perennial tropical (Brahmaputra) River. Water samples were collected from twelve locations during the monsoon, post-monsoon and pre-monsoon seasons. A characteristic trend in bioavailability was observed in the sequence of Zn > Cu > Pb > Cr > Cd, reflecting non-significant seasonal changes in dissolved and particulate phase metal fractions at all twelvelocations. Partition (or distribution) coefficients (K d s) for Cu (5.30–6.50), Zn (4.47–6.44), Pb (3.69–4.97) and Cr (3.25–5.15), reflect the influences of anionic inorganic constitutents (aqua ion complexes), environmental variables, and river hydrology. MINTEQA2 calculations showed that metal forms complexes with other inorganic ions such as Cl−, SO 4 2−, HCO3− and strong binding as organic complexes (for Cu and Pb) reduces their leaching potential to groundwater system. High log K d values (≥5.3) and significant spatial variations at locations R3 to R8 of Pb, Cu, and Zn during pre-monsoon period may be explained by the formation of complexes with organic ligands in sewage and domestic wastes (humic and fulvic acids). Multivariate statistical analysis revealed multi-metal co-contamination, mainly of Zn, Cu, Cd and Pb and dissolved nutrients, loading in different clusters, emphasizing the importance of climatic, anthropogenic, terrigenous and lithological sources as controlling factors for seasonal metal dynamics in the river water. • Seasonal dynamics of metal speciation and transport in tropical river were evaluated. • Order of bioavailability was different for the dissolved and particulate metal phases. • pH, TOC and dissolved nutrients/ions influence metal transport in Brahmaputra River. • Cd and Cr showed higher leaching potential towards the groundwater of the floodplains. • Partitioning coefficient suggest that sorption is significantly higher in the pre-monsoon. [ABSTRACT FROM AUTHOR]

The present study demonstrates potential utilization of lime-stabilized sewage sludge (SS) for construction purposes. SS samples were constituted using 0, 2, 4, 6 and 8% of lime by weight of the SS and cured for 7, 14 and 28 d. Stability of the lime-modified SS was evaluated through determination of geotechnical, microstructural and mineralogical properties. A large improvement in unconfined compressive strength (UCS) from 207 kPa to 1102 kPa was achieved after 28 d of curing SS with 6% lime. The improvement in UCS is attributed to formation of cementing compounds as a result of pozzolanic reactions. Marked reductions in swell pressure of 47, 51, 54 and 58% were obtained with the 2, 4, 6 and 8% lime treatments. Also, the plasticity index decreased with increasing lime content for different curing periods, indicating the SS becomes much more workable and less expansive. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) after lime treatment confirmed formation of the new compounds responsible for the improved engineering properties of SS. The study concludes that lime treatment can be an alternative to stabilize SS for potential use as a construction material for subbase of flexible pavement as per IRC (Indian Road Congress) 37–2012 guidelines. Image 1 • Sewage sludge (SS) exhibited expansive behaviour due to high content of Montmorillonite. • Lime (CaO) treatment improved SS strength, swelling and plasticity characteristics. • CaO induced cementation via gyrolite and hydrates of Ca and Ca–Al–OH silicates. • Unconfined compressive strength increased to 1102 kPa after 28 d of lime treatment. • SS treated with 6% CaO and cured 28 d found suitable for subbase pavement construction. [ABSTRACT FROM AUTHOR]

In this review, we present the environmental perspectives of the viruses and antiviral drugs related to SARS-CoV-2. The present review paper discusses occurrence, fate, transport, susceptibility, and inactivation mechanisms of viruses in the environment as well as environmental occurrence and fate of antiviral drugs, and prospects (prevalence and occurrence) of antiviral drug resistance (both antiviral drug resistant viruses and antiviral resistance in the human). During winter, the number of viral disease cases and environmental occurrence of antiviral drug surge due to various biotic and abiotic factors such as transmission pathways, human behaviour, susceptibility, and immunity as well as cold climatic conditions. Adsorption and persistence critically determine the fate and transport of viruses in the environment. Inactivation and disinfection of virus include UV, alcohol, and other chemical-base methods but the susceptibility of virus against these methods varies. Wastewater treatment plants (WWTPs) are major reserviors of antiviral drugs and their metabolites and transformation products. Ecotoxicity of antiviral drug residues against aquatic organisms have been reported, however more threatening is the development of antiviral resistance, both in humans and in wild animal reservoirs. In particular, emergence of antiviral drug-resistant viruses via exposure of wild animals to high loads of antiviral residues during the current pandemic needs further evaluation. ga1 • We analysed environmental perspectives of antiviral drugs and SARS-CoV-2. • Susceptibility and inactivation causes seasonality in the prevalence of SARS-CoV-2. • Surface-charge interactions govern environmental fate and transport of SARS-CoV-2. • Unprecedented use of antiviral drugs is hazardous to the environment. • Emergence of antiviral drug-resistant viruses needs further investigations. [ABSTRACT FROM AUTHOR]

Arsenic (As), a geogenic and extremely toxic metalloid can jeopardize terrestrial and aquatic ecosystems through environmental partitioning in natural soil-water compartment, geothermal and marine environments. Although, many researchers have investigated the decontamination potential of different mesoporous engineered bio sorbents for a suite of contaminants, still the removal efficiency of various pyrolyzed agricultural residues needs special attention. In the present study, rice straw derived biochar (RSBC) produced from slow pyrolysis process at 600 °C was used to remove As (V) from aqueous medium. Batch experiments were conducted at room temperature (25 ± 2 °C) under different initial concentrations (10, 30, 50, 100 μg L−1), adsorbent dosages (0.5–5 μg L−1), pH (4.0–10.0) and contact times (0–180 min). The adsorption equilibrium was established in 120 min. Adsorption process mainly followed pseudo–second order kinetics (R2 ≥ 0.96) and Langmuir isotherm models (R2 ≥ 0.99), and the monolayer sorption capacity of 25.6 μg g−1 for As (V) on RSBC was achieved. Among the different adsorbent dosages and initial concentrations used in the present study, 0.2 g L−1 (14.8 μg g−1) and 100 μg L−1 (13.1 μg g−1) were selected as an optimum parameters. A comparative analysis of RSBC with other pyrolyzed waste materials revealed that RSBC had comparable adsorption ability (per unit area). These acidic groups are responsible for the electron exchange (electrostatic attraction, ion-exchange, π–π/n-πinteractions) with the anionic arsenate, which facilitates optimum removal (>60%) at 7 < pH < pH PZC. The future areas of research will focus on decontamination of real wastewater samples containing mixtures of different emerging contaminants and installation of biofilter beds that contains different spent adsorbents/organic substrates (including biochar) for biopurification study in real case scenario. Image 1 • RSBC derived from slow pyrolysis showed q max of 25.6 μg g−1 for As in 120 min. • The adsorption followed pseudo second order and Langmir models (R2 > 0.90). • Immobilization of As was optimum (>60%) at pH 6 < pH PZC (7.20) with 2 g L−1 RSBC. • The binding mechanism is governed by electrostatic, π–π or ion-exchange reactions. [ABSTRACT FROM AUTHOR]