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1.
ASHRAE Journal ; 64(11):22-25, 2022.
Article in English | ProQuest Central | ID: covidwho-2112164

ABSTRACT

Researching and testing water to protect fish might seem obvious. Surprisingly, a parallel approach of analyzing and managing the predominant human exposure--indoor air--to optimize occupant well-being and productivity is not a priority for building management. We are indoors approximately 90% of the time, and health is people's most valuable asset, yet there is a lack of data relating indoor air quality (IAQ) to health outcomes. The most understandable obstacle is that relating IAQ to health outcomes is complex. The very fact that humans are resilient and able to withstand mild physiological stress without immediately obvious consequences makes correlating indoor exposures with health changes a difficult task. Despite these challenges, they need to pay attention to what IAQ data would tell. In fact, paying attention is not enough. They need to agree on what levels are good or bad and manage IAQ accordingly.

2.
Journal of Environmental Sciences ; 2022.
Article in English | ScienceDirect | ID: covidwho-2041926

ABSTRACT

Chlorine-based disinfectants are widely used for disinfection in wastewater treatment. The mechanism of the effects of chlorinated disinfection by-products on cyanobacteria was unclear. Herein, the physiological effects of chloroacetic acid (CAA) on Microcystis aeruginosa (M. aeruginosa), including acute toxicity, oxidative stress, apoptosis, production of microcystin-LR (MC-LR), and the microcystin transportation-related gene mcyH transcript abundance have been investigated. CAA exposure resulted in a significant change in the cell ultrastructure, including thylakoid damage, disappearance of nucleoid, production of gas vacuoles, increase in starch granule, accumulation of lipid droplets, and disruption of cytoplasm membranes. Meanwhile, the apoptosis rate of M. aeruginosa increased with CAA concentration. The production of MC-LR was affected by CAA, and the transcript abundance of mcyH decreased. Our results suggested that CAA poses acute toxicity to M. aeruginosa, and it could cause oxidative damage, stimulate MC-LR production, and damage cell ultrastructure. This study may provide information about the minimum concentration of CAA in the water environment, which is safe for aquatic organisms, especially during the global coronavirus disease 2019 pandemic period.

3.
Sustainability ; 14(17):10862, 2022.
Article in English | ProQuest Central | ID: covidwho-2024206

ABSTRACT

The waste generated by small-scale ultra-fresh juice producers, such as bistros and restaurants, has been little studied so far, mainly because it is unevenly distributed and dissipated in the economic ecosystem and would require high costs associated with transportation and subsequent recovery of bio composites. The present article seeks to offer solutions by providing sustainable methods to reduce their waste losses to a minimum and transform them into valuable products, with affordable equipment and techniques. The study focuses on the preliminary phase of quantitative analysis of fruit and vegetable by-products generated on a small scale, the results showing a mean 55% productivity in fresh juices. Due to the high amount of remnant water content in waste, a new process of mechanically pressing the resulting squeezed pulp was introduced, generating an additional yield in juice, ranging from 3.98 to 51.4%. Due to the rising trend in healthier lifestyle, the by-products were frozen or airdried for conservation in each of the processing stages, and the total phenolic compounds and antioxidant activity were analyzed in order to assess the traceability of these bioactive compounds to help maximize their transfer into future final products. The polyphenols transferred into by-products varied between 7 and 23% in pulps and between 6 and 20% in flours. The highest DPPH potential was found in flours, up to three-fold in comparison with the raw material, but the high dry substance content must be accounted for. The results highlight the potential of reusing the processing waste as a reliable source of bioactive compounds.

4.
Foods ; 11(16)2022 Aug 19.
Article in English | MEDLINE | ID: covidwho-2023327

ABSTRACT

This study aimed to develop a biodegradable container made of pork gelatin. Gelatin was extracted from pork skin by hot water at 80 °C, and containers were prepared by adding eggshell powder (20%) as a pore agent, and walnut powder (0.08 wt%; PEW1, 0.14 wt%; PEW2) to improve hardness. The blends were molded for each experiment and dried at 30 °C for 24 h, at 40 °C for 16 h, and at 121 °C for 16 h. The containers were analyzed with respect to morphological (SEM; scanning electron microscope), mechanical (tensile strain and stress), and thermal (DSA; differential scanning calorimetry and TGA; thermogravimetric analysis) properties, as well as biodegradability. SEM investigation showed a smoother surface for PEW1 than for PEW2. The tensile stress of PEW2 (37.86 MPa) was significantly higher than that of PEW1 (28.40 MPa), and the melting enthalpies were 137.60 J/g (PEW1) and 309.60 J/g (PEW2). TGA showed similar properties, but PEW2 contained more lignin; therefore, its decomposition temperature was higher. The PEW1 and PEW2 containers were completely biodegraded after approximately 7 and 11 weeks, respectively. Walnut shell powder increased the hardness, but slowed the biodegradation process. The applications of this biodegradable container are short-lived products such as food packaging.

5.
Applied Sciences ; 12(15):7652, 2022.
Article in English | ProQuest Central | ID: covidwho-1993927

ABSTRACT

A total of fourteen papers (ten research papers and four review papers) in various fields of horticulture are presented in this Special Issue, including such topics as the identification and accumulation of the bioactive compounds in various plant species;the effects of abiotic stresses on bioactive compound composition and content;and exploration of the best methods for bioactive compound extraction. [1], the authors investigated the nutritional profile and the antioxidant, antiproliferative, and antibacterial activities of five species of Brassica (cauliflower, broccoli, red cabbage, white cabbage, and Chinese cabbage);they found that these Brassica vegetables are excellent sources of polyphenols that showed moderate antiproliferative and antibacterial potential. [2], the effect of the bulk density and water-holding capacity of lignite substrate in comparison to mineral wool and the EC of nutrient solution on the plant morphological parameters, yield, and fruit quality of greenhouse cucumber were investigated, and the results suggest that both the substrate density and water-holding capacity positively affected the morphological features of the plants. In the fourth paper, reported by Karim and Yusof [4], it was found that the impregnation of spinach leaves with salicylic acid, γ-aminobutyric acid, and sucrose effectively improved the quality and storage ability by reducing chilling injury through improvement of the proline content.

6.
AORN Journal ; 116(2):145-159, 2022.
Article in English | ProQuest Central | ID: covidwho-1971227

ABSTRACT

Surgical smoke is the vaporous and gaseous byproduct of the use of heat-producing devices on tissue. The contents of surgical smoke include harmful chemicals, viable and nonviable material, and viruses. Personnel and patients experience an unpleasant odor when smoke is not evacuated and risk developing symptoms, such as headaches, throat irritation, and dizziness. The recently updated AORN "Guideline for surgical smoke safety" provides perioperative nurses with background information on surgical smoke and ways to mitigate the hazard. This article provides an overview of the guideline and discusses recommendations for a smoke-free environment, smoke evacuation and filtration, respiratory protection, education, policies and procedures, and quality. It also includes scenarios describing specific concerns in two patient care areas. Perioperative nurses should review the guideline in its entirety and apply the recommendations to protect personnel and patients from the dangers of surgical smoke.

7.
Molecules ; 27(9):2633, 2022.
Article in English | ProQuest Central | ID: covidwho-1842782

ABSTRACT

Flavonoids have the ability to control the accumulation of reactive oxygen species (ROS) via scavenger activity. [...]flavonoids are important secondary metabolites produced by plants with several functions related to the physiology of the growth and stress responses. [...]nutrients with anti-inflammatory and antioxidant properties may prevent or attenuate the inflammatory and vascular manifestations associated with COVID-19. [...]following healthy dietary patterns may have beneficial effects to contrast infection but still need to be explored. [...]natural compounds, owing to their medicinal, ecological, and other safe properties, are becoming popular potential candidates in preventing and treating peptic ulcers. At present, most data come from laboratory model tests. [...]the in vivo models of peptic ulcer include ulcers caused by oxidative damage, ethanol, NSAIDs, stress and Helicobacter pylori or acid-ethanol (ethanol or ethanol/HCl)-induced acute gastric ulcer models.

8.
Foods ; 11(9):1177, 2022.
Article in English | ProQuest Central | ID: covidwho-1837981

ABSTRACT

The purpose of this research was to develop formulations of chewing candies (CCs) in a sustainable manner by using berry by-products in combination with antimicrobial lactic acid bacteria (LAB) strains. To implement this aim, the optimal quantities of by-products from lyophilised raspberry (Rasp) and blackcurrant (Bcur) from the juice production industry were selected. Prior to use, Lactiplantibacillus plantarum LUHS135, Liquorilactobacillus uvarum LUHS245, Lacticaseibacillus paracasei LUHS244, and Pediococcus acidilactici LUHS29 strains were multiplied in a dairy industry by-product—milk permeate (MP). The antimicrobial activity of the selected ingredients (berry by-products and LAB) was evaluated. Two texture-forming agents were tested for the CC formulations: gelatin (Gl) and agar (Ag). In addition, sugar was replaced with xylitol. The most appropriate formulation of the developed CCs according to the product’s texture, colour, total phenolic compound (TPC) content, antioxidant activity, viable LAB count during storage, overall acceptability (OA), and emotions (EMs) induced in consumers was selected. It was established that the tested LAB inhibited three pathogens out of the 11 tested, while the blackcurrant by-products inhibited all 11 tested pathogens. The highest OA was shown for the CC prepared with gelatin in addition to 5 g of Rasp and 5 g of Bcur by-products. The Rasp and LUHS135 formulation showed the highest TPC content (147.16 mg 100 g−1 d.m.), antioxidant activity (88.2%), and LAB count after 24 days of storage (6.79 log10 CFU g−1). Finally, it was concluded that Gl, Rasp and Bcur by-products, and L. plantarum LUHS135 multiplied in MP are promising ingredients for preparing CCs in a sustainable manner;the best CC formula consisted of Gl, Rasp by-products, and LUHS135 and showed the highest OA (score 9.52) and induced the highest intensity of the EM ‘happy’ (0.231).

9.
Applied Sciences ; 12(6):3113, 2022.
Article in English | ProQuest Central | ID: covidwho-1760318

ABSTRACT

Featured ApplicationThis study shows the use of a by-product from the manufacture of a novel antiseptic/disinfectant (HOCl) to obtain a protein isolate from defatted soybean flour (a co-product from the soybean oil industry);an optimization process was carried out to create an industrial symbiosis.Defatted soybean flour is generated during the oil extraction process of soybean, and it has a protein content of ~50%. On the other hand, an alkaline solution of NaOH is produced during the electrolysis process of NaCl in a novel method used to make a potent disinfectant/antiseptic (HOCl). In the present work, we suggest using these two products to produce soy protein isolate (SPI), aiming to create an industrial symbiosis. A Box–Behnken experimental design was executed, and a surface response analysis was performed to optimize temperature, alkaline solution, and time used for SPI extraction. The SPI produced at optimal conditions was then characterized. The experimental results fit well with a second-order polynomial equation that could predict 93.15% of the variability under a combination of 70 °C, alkaline solution 3 (pH 12.68), and 44.7 min of the process. The model predicts a 49.79% extraction yield, and when tested, we obtained 48.30% within the confidence interval (46.66–52.93%). The obtained SPI was comparable in content and structure with a commercial SPI by molecular weight and molecular spectroscopy characterization. Finally, the urease activity (UA) test was negative, indicating no activity for trypsin inhibitor. Based on the functional properties, the SPI is suitable for food applications.

10.
Water ; 14(4):588, 2022.
Article in English | ProQuest Central | ID: covidwho-1715843

ABSTRACT

The consumption of illicit drugs represents a global social and economic problem. Using suitable analytical methods, monitoring, and detection of different illegal drugs residues and their metabolites in wastewater samples can help combat this problem. Our article defines a method to develop, validate, and practically applicate a rapid and robust analytical process for the evaluation of six naturally occurring cannabinoids (CBG, CBD, CBDV, CBN, THC, THCV), two cannabinoids in acidic form (CBDA, THCA-A), and the major cannabis-related human metabolite (THC-COOH). After SPE offline enrichment, we used a UPLC–ESI-MS/MS system, which permitted the determination of several by-products. Studied matrices were samples of different origins: (i) effluent water from a wastewater treatment plant in the Porto urban area;(ii) environmental water from Febros River, the last left-bank tributary of the Douro River. The multi-residue approach was substantiated and successfully employed to analyze the water samples collected in the above locations. The rapid and precise quantification of nine different cannabinoids in different water samples occurred within nine minutes at the ng L−1 level. The appearance of dozens of ng L−1 of some cannabis secondary metabolites, such as CBD, CBDA, CBN, THCA-A, indicates this plant species’ widespread usage among the general population in the considered area.

11.
Acs Chemical Health & Safety ; 29(1):27-38, 2022.
Article in English | Web of Science | ID: covidwho-1665669

ABSTRACT

The COVID-19 pandemic has called for the increased use of disinfectants worldwide in public facilities, transportation, hospitals, nursing homes, wastewater treatment facilities, and even common households to mitigate virus burden. Active ingredients in common disinfectants recommended for use against COVID-19 viruses include chemicals such as quaternary ammonium compounds (QACs), hydrogen peroxide, bleach (sodium hypochlorite), and alcohols. These disinfecting chemicals differ in their structures, properties, modes of action, environmental behaviors, and effects on human health upon exposure. Humans can be exposed to disinfecting chemicals mainly through dermal absorption, inhalation, and ingestion. The total exposure and relative contribution of each exposure route vary considerably among the disinfectants. QACs have been linked to occupational illnesses such as asthma and an increased risk of chronic obstructive pulmonary disease (COPD), whereas excess use of bleach, hydrogen peroxide, or alcohol-based disinfectants can cause respiratory damage and has been linked to an increased risk of developing and controlling asthma. Recent studies showed that the presence of QACs in human blood has been associated with changes in health biomarkers such as an increase in inflammatory cytokines, decreased mitochondrial function, and disruption of cholesterol homeostasis in a dose-dependent manner. Therefore, repeated human exposure to disinfectants during the pandemic has raised questions on exposure-related long-term health risks and occupational safety. Furthermore, in lieu of a lack of adequate knowledge and public awareness, these chemicals have been frequently used on porous surfaces, including fabrics/textiles and consumer plastics and even for disinfecting cloth facemasks, on which disinfectant chemical residues may persist for longer duration, causing potential degradation of plastic materials, releasing additives, and shedding microplastics. In addition, the increased use of these disinfectant chemicals and the subsequent discharge into wastewater may cause adverse impacts on aquatic ecosystems, accumulation on vegetables, and contamination of the food chain via wastewater irrigation and sludge application. This article provides a well-rounded understanding of the most common disinfectants and reviews modes of action of those disinfectants, their interactions with aquatic and terrestrial environments, the exposure to humans, and potential impacts to human health and safety.

12.
Huan Jing Ke Xue ; 43(2): 878-886, 2022 Feb 08.
Article in Chinese | MEDLINE | ID: covidwho-1643943

ABSTRACT

In order to reveal the pollution characteristics and risk levels of DBPs in typical drinking water sources in Wuhan under the COVID-19 pandemic, 26 sampling sites were selected in typical drinking water sources in Wuhan. N,N-diethyl-1,4-phenylenediamine spectrophotometry and gas chromatograph-micro-cell electron capture detector (GC-µECD) methods were used to detect residual chlorine disinfectants and DBPs in water, respectively, and their health and ecology risks were assessed. The results showed that free chlorine or total residual chlorine were detected in 16 of the 26 water samples, and the maximum concentration was 0.04 mg·L-1, which exceeded the limit of the surface water standard in China. The concentration of residual chlorine was higher in sampling sites near the outfall of a municipal sewage plant. There were 34 types of DBPs measured in 10 sampling sites, and 24 types of substances were detected with the detection rate of 10.00%-100.00%. The ρ (total DBPs) was in the range of 0.11-104.73 µg·L-1, with an average value of 7.26 µg·L-1. The concentration of chloroform was the highest among all the DBPs, ranging from 9.98 µg·L-1 to 11.15 µg·L-1, with an average value of 10.47 µg·L-1. The concentration of 2-bromo-2-iodoacetamide was the lowest, ranging from ND-0.11 µg·L-1, with an average value of 0.01 µg·L-1. The overall detection level of the DBPs area was low in this study area, and the result of the health risk assessment showed that the DBPs had no carcinogenic or non-carcinogenic health risks to human body. However, the results of the ecological risk assessment showed that chloroform presented a high ecological risk to aquatic organisms.


Subject(s)
COVID-19 , Disinfectants , Drinking Water , Water Pollutants, Chemical , Water Purification , Disinfectants/analysis , Disinfection , Drinking Water/analysis , Halogenation , Humans , Pandemics , Risk Assessment , SARS-CoV-2 , Water Pollutants, Chemical/analysis
13.
Agriculture ; 12(1):117, 2022.
Article in English | ProQuest Central | ID: covidwho-1632876

ABSTRACT

Colombia is the world’s largest producer of fique fibers (Furcraea bedinghausii), with a net production of 30,000 tons per year. This work proposes to revalue waste from the Colombian fique agroindustry. For this purpose, cellulose nanofibers were obtained from fique and used as reinforcement material to create acrylic superabsorbent hydrogels. Unreinforced acrylic hydrogels (AHR0) and acrylic hydrogels reinforced with fique nanofibers at 3% w/w (AHR3), 5% w/w (AHR5), and 10 % w/w (AHR10) were synthesized using the solution polymerization method. The best hydrogel formulation for agricultural purposes was chosen by comparing their swelling behavior, mechanical properties, and using scanning electron microscopy (SEM). By raising the nanofiber concentration to 3% (AHR3), the best-chosen formulation, the interaction between the nanofibers and the polymer matrix increased, which favored the network stability. However, beyond AHR3, there was a higher viscosity of the reactive system, which caused a reduction in the mobility of the polymer chains, thus disfavoring the swelling capacity. The reinforced hydrogel proposed in this study (AHR3) could represent a contribution to overcoming the problems of land dryness present in Colombia, an issue that will worsen in the coming years due to the climate emergency.

14.
Sci Total Environ ; 805: 150380, 2022 Jan 20.
Article in English | MEDLINE | ID: covidwho-1415774

ABSTRACT

An indole derivative umifenovir (Arbidol) is one of the most widely used antiviral drugs for the prevention and treatment of COVID-19 and some other viral infections. The purpose of the present study was to shed light on the transformation processes of umifenovir in municipal wastewater, including disinfection with active chlorine, as well as to assess the levels of the antiviral drug and its metabolites entering and accumulating in natural reservoirs under conditions of the SARS-CoV-2 pandemic. The combination of high-performance liquid chromatography with electrospray ionization high-resolution mass-spectrometry and inductively coupled plasma mass spectrometry was used for tentative identification and quantification of umifenovir and its transformation products in model reaction mixtures and real samples of wastewater, river water, biological sludge and bottom sediments taken at the wastewater treatment plant in Arkhangelsk, a large cultural and industrial center at the Russian North. Laboratory experiments allowed identifying fifteen bromine-containing transformation products, forming at the initial stages of the chlorination and fourteen classic volatile and semi volatile disinfection by-products with bromoform as the dominant one. Chlorinated derivatives are only the minor disinfection by-products forming by substitution of alkylamine group in the aromatic ring. The schemes of umifenovir transformation in reactions with dissolved oxygen and sodium hypochlorite are proposed. Two established primary transformation products formed by oxidation of the thioether group to sulfoxide and elimination of thiophenol were detected in noticeable concentrations in the wastewater together with their precursor. The level of umifenovir reached 1.3 mg kg-1 in the sludge and municipal wastewater treat contained 1 µg L-1 of that drug, while its removal during biological wastewater treatment was about 40%. Pronounced accumulation of umifenovir and its transformation products in biological sludge and bottom sediments of natural reservoirs may be a source of the future secondary pollution of the environment.


Subject(s)
COVID-19 , Water Pollutants, Chemical , Antiviral Agents , Humans , Indoles , Pandemics , SARS-CoV-2 , Waste Water , Water Pollutants, Chemical/analysis
15.
Environ Sci Technol ; 55(15): 10534-10541, 2021 08 03.
Article in English | MEDLINE | ID: covidwho-1270648

ABSTRACT

Intensified disinfection of wastewater during the COVID-19 pandemic increased the release of toxic disinfection by-products (DBPs). However, studies relating to the ecological impacts of DBPs on the aquatic environment remain insufficient. In this study, we comparatively investigated the toxicities and ecological risks of 17 typical, halogenated DBPs to three trophic levels of organisms in the freshwater ecosystem, including phytoplankton (Scenedesmus sp.), zooplankton (Daphnia magna), and fish (Danio rerio). Toxicity of DBPs was found to be species-specific: Scenedesmus sp. was the most sensitive to haloacetic acids, while D. magna was the most sensitive to haloacetonitriles and trihalomethanes. Specific to each DBP, toxicities were also related to their classes and substituted halogen atoms. Damage to photosystems and oxidative stress served as the potential mechanisms for DBPs toxicity to microalgae. The different sensitivities to DBPs indicate that a battery of bioassays with organisms at different trophic levels is necessary to determine the ecotoxicity of DBPs. Furthermore, the ecological risks of DBPs were assessed by calculating the risk quotients (RQs) based on toxicity data from multiple bioassays. The cumulative RQs of DBPs to all the organisms were greater than 1.0, indicating high ecological risks of DBPs in wastewater effluents.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Animals , Aquatic Organisms , Disinfectants/toxicity , Disinfection , Ecosystem , Halogenation , Humans , Pandemics , SARS-CoV-2 , Trihalomethanes , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
16.
Sci Total Environ ; 790: 148030, 2021 Oct 10.
Article in English | MEDLINE | ID: covidwho-1244824

ABSTRACT

Due to the spread of coronavirus disease 2019 (COVID-19), large amounts of antivirals were consumed and released into wastewater, posing risks to the ecosystem and human health. Ozonation is commonly utilized as pre-oxidation process to enhance the disinfection of hospital wastewater during COVID-19 spread. In this study, the transformation of ribavirin, antiviral for COVID-19, during ozone/PMS­chlorine intensified disinfection process was investigated. •OH followed by O3 accounted for the dominant ribavirin degradation in most conditions due to higher reaction rate constant between ribavirin and •OH vs. SO4•- (1.9 × 109 vs. 7.9 × 107 M-1 s-1, respectively). During the O3/PMS process, ribavirin was dehydrogenated at the hydroxyl groups first, then lost the amide or the methanol group. Chloride at low concentrations (e.g., 0.5- 2 mg/L) slightly accelerated ribavirin degradation, while bromide, iodide, bicarbonate, and dissolved organic matter all reduced the degradation efficiency. In the presence of bromide, O3/PMS process resulted in the formation of organic brominated oxidation by-products (OBPs), the concentration of which increased with increasing bromide dosage. However, the formation of halogenated OBPs was negligible when chloride or iodide existed. Compared to the O3/H2O2 process, the concentration of brominated OBPs was significantly higher after ozonation or the O3/PMS process. This study suggests that the potential risks of the organic brominated OBPs should be taken into consideration when ozonation and ozone-based processes are used to enhance disinfection in the presence of bromide amid COVID-19 pandemic.


Subject(s)
COVID-19 , Ozone , Water Pollutants, Chemical , Water Purification , Antiviral Agents , Disinfection , Ecosystem , Humans , Hydrogen Peroxide , Oxidation-Reduction , Pandemics , Ribavirin , SARS-CoV-2 , Water Pollutants, Chemical/analysis
17.
Sci Total Environ ; 770: 145344, 2021 May 20.
Article in English | MEDLINE | ID: covidwho-1065585

ABSTRACT

The high chlorine dosages in wastewater treatment plants during the COVID-19 pandemic may result in increased formation of disinfection by-products (DBPs), posing great threat to the aquatic ecosystem of the receiving water body and the public health in the downstream area. However, limited information is available on the effect of biological wastewater treatment processes on the formation of CX3R-type DBPs. This study investigated the effect of oxidation ditch (OD) and anaerobic-anoxic-oxic (AAO), two widely used biological wastewater treatment processes, on the formation of five classes of CX3R-type DBPs, including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetaldehydes (HALs), haloacetonitriles (HANs) and halonitromethanes (HNMs), during chlorination. Experimental results showed that biological treatment effectively reduced the dissolved organic carbon (DOC) and UV254, while it increased the dissolved organic nitrogen (DON), and therefore the ratio of DON/DOC. In addition, increases in the contents of soluble microbial product- and humic acid-like matters, and the transformation of high molecular weight (MW) fractions in the dissolved organic matter into low MW fractions were observed after OD and AAO processes. Although biological treatment effectively decreased the formation of Cl-THMs, Cl-HAAs, Cl-HANs and Cl-HNMs, the formation of DBCM, DBAA, BDCAA, DBCAA, DCAL, TCAL and DBAN (where C = chloro, B = bromo, D = di, T = tri) all increased significantly, due to the increased formation reactivity. Moreover, biological treatment increased the ratio of bromide/DOC and bromine incorporation into THMs, HAAs and DHANs except for HALs and THANs. Different from previous studies, this study revealed that biological treatment increased the formation of some DBPs, especially brominated DBPs, despite the efficient removal of organic matters. It provides insights into the DBP risk control in wastewater treatment, particularly during the COVID-19 pandemic.

18.
Chem Eng J ; 405: 126893, 2021 Feb 01.
Article in English | MEDLINE | ID: covidwho-952653

ABSTRACT

The unprecedented global spread of the severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 is depicting the distressing pandemic consequence on human health, economy as well as ecosystem services. So far novel coronavirus (CoV) outbreaks were associated with SARS-CoV-2 (2019), middle east respiratory syndrome coronavirus (MERS-CoV, 2012), and SARS-CoV-1 (2003) events. CoV relates to the enveloped family of Betacoronavirus (ßCoV) with positive-sense single-stranded RNA (+ssRNA). Knowing well the persistence, transmission, and spread of SARS-CoV-2 through proximity, the faecal-oral route is now emerging as a major environmental concern to community transmission. The replication and persistence of CoV in the gastrointestinal (GI) tract and shedding through stools is indicating a potential transmission route to the environment settings. Despite of the evidence, based on fewer reports on SARS-CoV-2 occurrence and persistence in wastewater/sewage/water, the transmission of the infective virus to the community is yet to be established. In this realm, this communication attempted to review the possible influx route of the enteric enveloped viral transmission in the environmental settings with reference to its occurrence, persistence, detection, and inactivation based on the published literature so far. The possibilities of airborne transmission through enteric virus-laden aerosols, environmental factors that may influence the viral transmission, and disinfection methods (conventional and emerging) as well as the inactivation mechanism with reference to the enveloped virus were reviewed. The need for wastewater epidemiology (WBE) studies for surveillance as well as for early warning signal was elaborated. This communication will provide a basis to understand the SARS-CoV-2 as well as other viruses in the context of the environmental engineering perspective to design effective strategies to counter the enteric virus transmission and also serves as a working paper for researchers, policy makers and regulators.

19.
Sci Total Environ ; 741: 140445, 2020 Nov 01.
Article in English | MEDLINE | ID: covidwho-610875

ABSTRACT

The outbreak of coronavirus infectious disease-2019 (COVID-19) pneumonia raises the concerns of effective deactivation of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in medical wastewater by disinfectants. In this study, we evaluated the presence of SARS-CoV-2 viral RNA in septic tanks of Wuchang Cabin Hospital and found a striking high level of (0.5-18.7) × 103 copies/L after disinfection with sodium hypochlorite. Embedded viruses in stool particles might be released in septic tanks, behaving as a secondary source of SARS-CoV-2 and potentially contributing to its spread through drainage pipelines. Current recommended disinfection strategy (free chlorine ≥0.5 mg/L after at least 30 min suggested by World Health Organization; free chlorine above 6.5 mg/L after 1.5-h contact by China Centers for Disease Control and Prevention) needs to be reevaluated to completely remove SARS-CoV-2 viral RNA in non-centralized disinfection system and effectively deactivate SARS-CoV-2. The effluents showed negative results for SARS-CoV-2 viral RNA when overdosed with sodium hypochlorite but had high a level of disinfection by-product residuals, possessing significant ecological risks.


Subject(s)
Coronavirus Infections , Disinfection , Pandemics , Pneumonia, Viral , Betacoronavirus , COVID-19 , China , Humans , Motor Vehicles , RNA, Viral/analysis , SARS-CoV-2
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