Wastewater Surveillance of SARS-CoV-2 at a Canadian University Campus and the Impact of Wastewater Characteristics on Viral RNA Detection.

Because of the increased population density, high-risk behavior of young students, and lower vaccination rates, university campuses are considered hot spots for COVID-19 transmission. This study monitored the SARS-CoV-2 RNA levels in the wastewater of a Canadian university campus for a year to provide actionable information to safely manage COVID-19 on campus. Wastewater samples were collected from the campus sewer and residence buildings to identify changes, peaks, and hotspots and search for associations with campus events, social gatherings, long weekends, and holidays.

Fate and removal of silver nanoparticles during sludge conditioning and their impact on soil health after simulated land application.

The growing use of silver nanoparticles (AgNPs) in personal care products and clothing has increased their concentrations in wastewater and subsequently in sludge raising concerns about their fate and toxicity during wastewater treatment and after land application of sludge. This research investigated the fate and removal of AgNPs during chemical conditioning of anaerobically digested sludge and their impact on soil bacteria and health after land application. Ferric chloride (FeCl), alum (Al (SO) • (14-18) HO), and synthetic (polyacrylamide) polymer were used for sludge conditioning.

Transformation of Silver Nanoparticles (AgNPs) during Lime Treatment of Wastewater Sludge and Their Impact on Soil Bacteria.

This study investigated the impact of lime stabilization on the fate and transformation of AgNPs. It also evaluated the changes in the population and diversity of the five most relevant bacterial phyla in soil after applying lime-stabilized sludge containing AgNPs. The study was performed by spiking an environmentally relevant concentration of AgNPs (2 mg AgNPs/g TS) in sludge, applying lime stabilization to increase pH to above 12 for two hours, and applying lime-treated sludge to soil samples.

Direct and quantitative capture of viable bacteriophages from experimentally contaminated indoor air: A model for the study of airborne vertebrate viruses including SARS-CoV-2.

Aim: The air indoors has profound health implications as it can expose us to pathogens, allergens and particulates either directly or via contaminated surfaces. There is, therefore, an upsurge in marketing of air decontamination technologies, but with no proper validation of their claims. We addressed the gap through the construction and use of a versatile room-sized (25 m ) chamber to study airborne pathogen survival and inactivation.

Impact of anaerobically digested silver and copper oxide nanoparticles in biosolids on soil characteristics and bacterial community.

This study investigated whether 2 and 30 mg AgNPs or CuONPs/g TS present in treated sludge (biosolids) may impact the soil health by monitoring the soil characteristics and soil bacterial community for 105 days after the application of biosolids. AgNPs or CuONPs/g TS were first anaerobically digested with mixed primary and secondary sludge rather than adding pristine nanoparticles to biosolids directly. Both environmentally relevant (under the USEPA ceiling concentration limits) and high concentrations of AgNPs and CuONPs were tested.

Effect of polymeric support material on biofilm development, bacterial population, and wastewater treatment performance in anaerobic fixed-film systems.

This study evaluated the performance of high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyvinylchloride (PVC), polypropylene (PP), polyvinylidene fluoride (PVDF) and polymethyl methacrylate (acrylic) when used as a support media in anaerobic attached-growth wastewater treatment systems. A combination of physical and chemical (total solids, protein, phosphorus, ammonia, chemical oxygen demand) methods, environmental scanning electron microscopy (ESEM) and Live/Dead viability assay) and genetic sequencing over a period of 81 days was used to provide an in-depth understanding of the impact of different polymer materials on biofilm formation, bacteria population, and wastewater treatment performance. The results showed that hydrophobic polymeric materials (i.

Peracetic acid (PAA) and low-pressure ultraviolet (LP-UV) inactivation of Coxsackievirus B3 (CVB3) in municipal wastewater individually and concurrently.

Domestic wastewater (WW) contains a large number of pathogenic viruses that are not significantly reduced in most WW treatment processes and are found in high numbers in the effluent of conventionally disinfected WW. In this study, secondary WW effluent bench-scale disinfection efficacy experiments with two different peracetic acid (PAA) formulations (15 and 22% peracetic acid) and low-pressure ultraviolet irradiation (LP-UV) were carried out using Coxsackievirus B3 (CVB3) as a clinically relevant surrogate for enteric viruses and Escherichia coli (E. coli) as the disinfection efficacy control.

Development of a sensitive and false-positive free PMA-qPCR viability assay to quantify VBNC Escherichia coli and evaluate disinfection performance in wastewater effluent.

The detection and quantification of viable Escherichia coli cells in wastewater treatment plant effluent is very important as it is the main disinfection efficacy parameter for assessing its public health risk and environmental impact. The aim of this study was to develop a sensitive and false-positive free propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR) assay to quantify the viable but non-culturable (VBNC) E. coli present in secondary wastewater effluent after chlorine disinfection.

Decontamination of indoor air to reduce the risk of airborne infections: Studies on survival and inactivation of airborne pathogens using an aerobiology chamber.

Background: Although indoor air can spread many pathogens, information on the airborne survival and inactivation of such pathogens remains sparse.

Methods: Staphylococcus aureus and Klebsiella pneumoniae were nebulized separately into an aerobiology chamber (24.0 m).

Eliminating false positives in a qPCR assay for the detection of the uidA gene in Escherichia coli.

Due to contaminant Escherichia coli DNA present in recombinant Taq polymerase reagents, it is not possible to reliably detect low levels of E. coli in samples using the quantitative polymerase chain reaction (qPCR) assay. Native Taq polymerase was successfully used in this study to detect five uidA gene copies (5 fg of genomic DNA) of the uidA gene.

Aptamer-based viability impedimetric sensor for bacteria.

The development of an aptamer-based viability impedimetric sensor for bacteria (AptaVISens-B) is presented. Highly specific DNA aptamers to live Salmonella typhimurium were selected via the cell-systematic evolution of ligands by exponential enrichment (SELEX) technique. Twelve rounds of selection were performed; each comprises a positive selection step against viable S.

Aptamer-based impedimetric sensor for bacterial typing.

The development of an aptamer-based impedimetric sensor for typing of bacteria (AIST-B) is presented. Highly specific DNA aptamers to Salmonella enteritidis were selected via Cell-SELEX technique. Twelve rounds of selection were performed; each comprises a positive selection step against S.

Experimental evaluation of an automated endoscope reprocessor with in situ generation of peracetic acid for disinfection of semicritical devices.

Objective: To evaluate the effectiveness of a high-level disinfection solution generated inside an endoscope processing system for decontaminating external and internal surfaces of experimentally contaminated heat-sensitive medical devices.

Methods: The American Society for Testing and Materials Simulated-Use Test protocol (E1837-02), which incorporates a soil load in each inoculum, was used to evaluate the efficacy of the system when processing 4 common types of endoscopes contaminated separately with 5 types of nosocomial pathogens: Pseudomonas aeruginosa (ATCC 15442), spores of Clostridium difficile (ATCC 9689), a glutaraldehyde-resistant strain of Mycobacterium chelonae, a vancomycin-resistant strain of Enterococcus faecalis, and a methicillin-resistant strain of Staphylococcus aureus. Rinse solution samples from channels and from surfaces of the processed endoscopes were tested for any microbicidal residues.