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1.
Chemosphere ; 333: 138885, 2023 Aug.
Article in English | MEDLINE | ID: covidwho-2327429

ABSTRACT

The COVID-19 pandemic resulted in increasing the usage of iodinated contrast media (ICM), and thus an increase in the prevalence of ICM-contaminated wastewater. While ICM is generally safe, this has the potential to be problematic because as medical wastewater is treated and disinfected, various ICM-derived disinfection byproducts (DBPs) may be generated and released into the environment. However, little information was available about whether ICM-derived DBPs are toxic to aquatic organisms. In this study, the degradation of three typical ICM (iopamidol, iohexol, diatrizoate) at initial concentration of 10 µM and 100 µM in chlorination and peracetic acid without or with NH4+ was investigated, and the potential acute toxicity of treated disinfected water containing potential ICM-derived DBPs on Daphnia magna, Scenedesmus sp. and Danio rerio was tested. The degradation results suggested that only iopamidol was significantly degraded (level of degradation >98%) by chlorination, and the degradation rate of iohexol and diatrizoate were significantly increased in chlorination with NH4+. All three ICM were not degraded in peracetic acid. The toxicity analysis results indicate that only the disinfected water of iopamidol and iohexol by chlorination with NH4+ were toxic to at least one aquatic organism. These results highlighted that the potential ecological risk of ICM-contained medical wastewater by chlorination with NH4+ should not be neglected, and peracetic acid may be an environment-friendly alternative for the disinfection of wastewater containing ICM.


Subject(s)
COVID-19 , Iodine Compounds , Scenedesmus , Water Pollutants, Chemical , Animals , Humans , Iohexol/toxicity , Iohexol/analysis , Iopamidol , Disinfection/methods , Diatrizoate/analysis , Daphnia , Zebrafish , Peracetic Acid , Wastewater/toxicity , Pandemics , Contrast Media/toxicity , Contrast Media/analysis , Water/analysis , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Halogenation
2.
Journal of Water Resource and Protection ; 14(4):349-384, 2022.
Article in English | CAB Abstracts | ID: covidwho-2315361

ABSTRACT

In COVID-19 pandemic in the world, alcohol (ethanol) can be listed as a sterilizing disinfectant. It absolutely played a Messianic function on the sterilization effect. And it is said that it has one more function called "salinity reduction" but that function is not widely known. The two functions (Sterilization & Salinity Reduction) mentioned above are extremely important regarding the theme of "raw seawater into beverage" in this study. It is thought that if the two functions are achieved other water quality items such as NO-2 and other items can be cleared with comparative ease. To put briefly the feature of modern waterworks in a word, it can be said that "source of water is river water and its sterilization is chlorine". In this study, we set up it with a completely new sanitization method (great reset), that is, "source of water is mixtures (seawater and rainwater) and its sterilization is ethanol". And it can be also expected that the capture and storage of ethanol as a renewable resource is basically possible by utilizing sunlight as a natural power. Therefore, we think that this resolves itself into a question of the choice (sense of value/culture) of the users. It means that how users finally balance out with three factors, i.e., cost, risk (safety) and benefit. Based on the viewpoint mentioned above, we examined the possibility of raw seawater into beverage using ethanol as a renewable resource to create humankind's wisdom to the settlement (breakthrough) of the water scarcity in the world including Asia and Africa. As a result, we have obtained the new findings that suggest the possibility of raw seawater into beverage using ethanol as a renewable resource.

3.
New Journal of Chemistry ; 46(39):18824-18831, 2022.
Article in English | EMBASE | ID: covidwho-2295520

ABSTRACT

The study of tautomerism in biologically relevant heterocycles is essential, as it directly affects their chemical properties and biological function. Lactam-lactim tautomerization in pyridine/pyrazine derivatives is such a phenomenon. Favipiravir, a pyrazine derivative, is an essential antiviral drug molecule having notable performance against SARS-CoV-2. Along with a better yielding synthetic method for favipiravir, we have also investigated the lactam-lactim tautomerization of favipiravir and its analogous molecules. Most of these molecules were crystalized and studied for various interactions in their lattice. Many interesting supramolecular interactions such as hydrogen bonding, pi-pi stacking and halogen bonding were revealed during the analysis. Some of these structures show interesting F-F halogen bonding and water channels in their solid state.Copyright © 2022 The Royal Society of Chemistry.

4.
Revista Higiene Alimentar ; 36(295), 2022.
Article in Portuguese | CAB Abstracts | ID: covidwho-2272726

ABSTRACT

Recently, with the coronavirus pandemic, the eating habits of the population have been modified, observing the search for healthy diet. In this sense, the consumption of fruits and vegetables has increased, and the hygiene is a fundamental step in quality control, since fruits and vegetables can be consumed in natura. The objective of the work was to elaborate a review about the main chemical sanitizers used in the sanitization of fruits and vegetables. The study is a review based on scientific publications, using the combination of the following descriptors: hygiene, fruits and vegetables, sanitizers and sanitizing. It was possible to verify that the most used sanitizer in the sanitization of fruits and vegetables is chlorine and its derivatives, in concentrations from 100 to 200 ppm, normally for 15 minutes. Ozone could destroy numerous microorganisms and for its sanitizing effect it is necessary to have a longer exposure time, on average up to 30 minutes. When using organic acids (acetic, citric, lactic and peracetic acid), the concentrations vary up to 2% and the average exposure time is a few minutes, which can be used in combination or not. However, its use is not always effective. It is concluded that the application of each type of sanitizer varies according to its concentrations, pH, exposure time to the treatment and the type of fruit or vegetable to be sanitized.

5.
Pharmaceuticals: Boon or Bane ; : 69-89, 2023.
Article in English | Scopus | ID: covidwho-2261636

ABSTRACT

Every year, a million tonnes of pharmaceutical waste is generated around the globe. The major pharmaceutical products include syringes, masks, PPE kits, unused vaccines, antibiotics, etc. Its production was at a steady rate before the pandemic, but during the pandemic, the demand increased many-fold and so did the production. The widespread use of these pharmaceutical products during the COVID-19 pandemic has created an alarming situation around the world. All our landfills, oceans, and rivers are flooded with pharmaceutical waste. The unused antibiotics after unsafe disposal led to the presence of antibiotics in soil and water, which led to the antibiotic-resistant issue. In the current chapter, the authors suggest a drastic change in pharmacy waste before and after the pandemic and ways to minimize the environmental and health risks. © 2023 Nova Science Publishers, Inc. All rights reserved.

6.
Water Res ; 235: 119927, 2023 May 15.
Article in English | MEDLINE | ID: covidwho-2286181

ABSTRACT

Ambroxol hydrochloride (AMB) and bromhexine hydrochloride (BRO) are classic expectorants and bronchosecretolytic pharmaceuticals. In 2022, both AMB and BRO were recommended by medical emergency department of China to alleviate cough and expectoration for symptoms caused by COVID-19. The reaction characteristics and mechanism of AMB/BRO with chlorine disinfectant in the disinfection process were investigated in this study. The reaction of chlorine with AMB/BRO were well described by a second-order kinetics model, first-order in both AMB/BRO and chlorine. The second order rate reaction constant of AMB and BRO with chlorine at pH 7.0 were 1.15 × 102 M-1s-1 and 2.03 × 102 M-1s-1, respectively. During chlorination, a new class of aromatic nitrogenous disinfection by-products (DBPs) including 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were identified as the intermediate aromatic DBPs by gas chromatography-mass spectrometry. The effect of chlorine dosage, pH, and contact time on the formation of 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were evaluated. In addition, it was found that bromine in AMB/BRO were vital bromine source to greatly promote the formation of classic brominated DBPs, with the highest Br-THMs yields of 23.8% and 37.8%, respectively. This study inspired that bromine in brominated organic compounds may be an important bromine source of brominated DBPs.


Subject(s)
Ambroxol , Bromhexine , COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Humans , Disinfection/methods , Halogenation , Expectorants , Bromine/chemistry , Chlorine/chemistry , Water Purification/methods , Disinfectants/analysis , Halogens , Chlorides , Water Pollutants, Chemical/chemistry
7.
Int J Hyg Environ Health ; 249: 114138, 2023 04.
Article in English | MEDLINE | ID: covidwho-2243284

ABSTRACT

INTRODUCTION: Consistent and effective practice of water treatment, sanitation, and hygiene (WASH) behaviour is an indispensable requisite for realizing health improvements among children living in low-income areas with challenging hygienic conditions. Sustainably achieving such a behaviour change is challenging but more likely to be realized during epidemics, when health threats are high and the dissemination of information on preventative measures is intense. Our study conducted cross-sectional surveys in Surkhet District Nepal, before and during the Covid-19 pandemic to assess the impact of water safety interventions and hygiene training implemented before and during the pandemic on WASH conditions and practices and to assess the association of these changes with child health. METHODS: Information on WASH infrastructure, WASH behaviour, nutrition, and child health, including on parasitic infections, was obtained before and during the Covid-19 pandemic in spring 2018 and spring 2021, from 589 children aged between 6 months and 10 years and their caregivers. Data was collected through quantitative, structured face-to-face interviews, observations, health examinations of children including anthropometric measurements, analysis of children's stool, and water quality analysis. The association of changes in WASH factors with changes in child health was analysed using multivariate generalized estimating equations for repeated measures. RESULTS: Water safety management was significantly improved by the introduction of chlorination to piped water supply systems, which served 40% of households. In addition, the percentage of households using a ceramic water filter increased from 12.2% to 34.8%. Large and significant changes were observed in handwashing behaviour (frequency, use of soap and washing at critical times) and infrastructure: 35% of households constructed a new handwashing station. Kitchen and household hygiene also improved. An additional 22% of households improved the cleanliness of the toilet. The number of houses with a cemented floor increased by 20%. WASH changes were significantly associated with improved child health: the chlorination of piped water supply reduced odds ratios for diarrhoea (OR = 0.36, 95% CI = 0.15-0.88, p = 0.025), respiratory difficulties (OR = 0.39, 95% CI = 0.16-0.92, p = 0.033), fever (OR = 0.42, 95% CI = 0.26-0.71, p = 0.001) and cough (OR = 0.58, 95% CI = 0.36-0.93, p = 0.024), and. The frequency of handwashing with soap was associated with significantly reduced odds ratios for infections with Giardia lamblia (OR = 0.68, 95% CI = 0.50-0.91, p = 0.011), stunting and wasting (OR = 0.75, 95% CI = 0.66-0.92, p = 0.003) and fever (OR = 0.85, 95% CI = 0.75-0.96, p = 0.008),. The presence of a handwashing station at baseline was associated with significantly reduced odds ratios for respiratory difficulties (OR = 0.45, 95% CI = 0.26-0.78, p = 0.004). The construction of a handwashing station between baseline and endline was significantly associated with reduced odds ratios for pale conjunctiva (OR = 0.32, 95% CI = 0.17-0.60, p < 0.001), which is a clinical sign of iron deficiency and anaemia, respiratory difficulties (OR = 0.39, 95% CI = 0.17-0.89, p = 0.026) and cough (OR = 0.44, 95% CI = 0.26-0.76, p = 0.003). Using a clean container for the transport of drinking water was significantly associated with reduced odds ratios for infections with Giardia lamblia (OR = 0.39, 95% CI = 0.16-0.93, p = 0.033) and diarrhoea (OR = 0.48, 95% CI = 0.24-0.96, p = 0.038). Similarly, a cemented floor in the household was significantly associated with reduced odd ratios for diarrhoea (OR = 0.38, 95% CI = 0.16-0.87, p = 0.022) and infections with Giardia lamblia (OR = 0.44, 95% CI = 0.19-1.02, p = 0.056). CONCLUSION: WASH training and the promotion of preventative measures during the Covid-19 pandemic supported improved water safety management and hygiene behaviour, which resulted in a reduction in infectious diseases among children in the study area.


Subject(s)
COVID-19 , Water Purification , Child , Humans , Infant , Cross-Sectional Studies , Child Health , Nepal/epidemiology , Soaps , Cough/epidemiology , Pandemics , COVID-19/epidemiology , Hygiene , Sanitation , Diarrhea/epidemiology , Water Supply
8.
Front Microbiol ; 13: 1083974, 2022.
Article in English | MEDLINE | ID: covidwho-2236135

ABSTRACT

A large number of pathogenic microorganisms exist in medical wastewater, which could invade the human body through the water and cause harm to human health. With the global pandemic coronavirus (COVID-19), public health safety become particularly important, and medical wastewater treatment is an important part of it. In particular, electrochemical disinfection technology has been widely studied in medical wastewater treatment due to its greenness, high efficiency, convenient operation, and other advantages. In this paper, the development status of electrochemical disinfection technology in the treatment of medical wastewater is reviewed, and an electrochemical three-stage disinfection system is proposed for the treatment of medical wastewater. Moreover, prospects for the electrochemical treatment of medical wastewater will be presented. It is hoped that this review could provide insight and guidance for the research and application of electrochemical disinfection technology to treat medical wastewater.GRAPHICAL ABSTRACT.

9.
Environ Sci Technol ; 56(23): 16929-16939, 2022 Dec 06.
Article in English | MEDLINE | ID: covidwho-2133140

ABSTRACT

Acetaminophen is widely used to treat mild to moderate pain and to reduce fever. Under the worldwide COVID-19 pandemic, this over-the-counter pain reliever and fever reducer has been drastically consumed, which makes it even more abundant than ever in municipal wastewater and drinking water sources. Chlorine is the most widely used oxidant in drinking water disinfection, and chlorination generally causes the degradation of organic compounds, including acetaminophen. In this study, a new reaction pathway in the chlorination of acetaminophen, i.e., oxidative coupling reactions via acetaminophen radicals, was investigated both experimentally and computationally. Using an ultraperformance liquid chromatograph coupled to an electrospray ionization-triple quadrupole mass spectrometer, we detected over 20 polymeric products in chlorinated acetaminophen samples, some of which have structures similar to the legacy pollutants "polychlorinated biphenyls". Both C-C and C-O bonding products were found, and the corresponding bonding processes and kinetics were revealed by quantum chemical calculations. Based on the product confirmation and intrinsic reaction coordinate computations, a pathway for the formation of the polymeric products in the chlorination of acetaminophen was proposed. This study suggests that chlorination may cause not only degradation but also upgradation of a phenolic compound or contaminant.


Subject(s)
COVID-19 , Disinfectants , Drinking Water , Water Pollutants, Chemical , Water Purification , Humans , Disinfection , Chlorine , Drinking Water/chemistry , Acetaminophen , Molecular Weight , Pandemics , Water Pollutants, Chemical/chemistry , Halogenation , Pain , Disinfectants/chemistry
10.
Environ Monit Assess ; 194(12): 884, 2022 Oct 14.
Article in English | MEDLINE | ID: covidwho-2093260

ABSTRACT

In the last few decades, environmental contaminants (ECs) have been introduced into the environment at an alarming rate. There is a risk to human health and aquatic ecosystems from trace levels of emerging contaminants, including hospital wastewater (HPWW), cosmetics, personal care products, endocrine system disruptors, and their transformation products. Despite the fact that these pollutants have been introduced or detected relatively recently, information about their characteristics, actions, and impacts is limited, as are the technologies to eliminate them efficiently. A wastewater recycling system is capable of providing irrigation water for crops and municipal sewage treatment, so removing ECs before wastewater reuse is essential. Water treatment processes containing advanced ions of biotic origin and ECs of biotic origin are highly recommended for contaminants. This study introduces the fundamentals of the treatment of tertiary wastewater, including membranes, filtration, UV (ultraviolet) irradiation, ozonation, chlorination, advanced oxidation processes, activated carbon (AC), and algae. Next, a detailed description of recent developments and innovations in each component of the emerging contaminant removal process is provided.


Subject(s)
Cosmetics , Endocrine Disruptors , Ozone , Water Pollutants, Chemical , Water Purification , Charcoal , Ecosystem , Endocrine Disruptors/analysis , Environmental Monitoring , Humans , Sewage , Wastewater/analysis , Water Pollutants, Chemical/analysis
11.
Water ; 14(19):3009, 2022.
Article in English | ProQuest Central | ID: covidwho-2066634

ABSTRACT

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are emerging contaminants leading to severe worldwide health problems. Chlorination, a widely used procedure, was extensively explored as one of the main methods to remove ARB and ARGs in recent years. In this study, to enrich the analyses of chlorination, several comprehensive effects of the chlorine disinfection system on ARB and their conjugative transfer ability were explored. The results presented that the low dose of chlorine (<3-log inactivation rate) had little influence on the survival of bacteria in terms of their capacity for conjugative transfer and antibiotic resistance. The high dose of chlorine (>3-log inactivation rate) triggered cell membrane changes, with little influence on the bacteria in terms of their antibiotic resistance. However, their capacity for conjugative transfer sharply decreased. Minor consumption of chloramphenicol was achieved with the chlorine dose applied in the disinfection system. Monochloroacetonitrile (MCAN) had limited effects on the frequency of conjugative transfer, indicating that the existence of MCAN would not aggravate the dissemination of ARGs by conjugative transfer. The overall impacts of the chlorine disinfection system with different containments on antibiotic resistance need further investigation.

12.
Water Res ; 223: 119021, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-2004603

ABSTRACT

Due to the Covid-19 pandemic, the worldwide biocides application has been increased, which will eventually result in enhanced residuals in treated wastewater. At the same time, chlorine disinfection of secondary effluents and hospital wastewaters has been intensified. With respect to predicted elevated exposure in wastewater, the chlorination kinetics, transformation pathways and toxicity evolution were investigated in this study for two typical isothiazolinone biocides, methyl-isothiazolinone (MIT) and chloro-methyl-isothiazolinone (CMIT). Second-order rate constants of 0.13 M-1·s-1, 1.95 × 105 M-1·s-1 and 5.14 × 105 M-1·s-1 were determined for the reaction of MIT with HOCl, Cl2O and Cl2, respectively, while reactivity of CMIT was around 1-2 orders of magnitude lower. While chlorination of isothiazolinone biocides at pH 7.1 was dominated by Cl2O-oxidation, acidic pH and elevated Cl- concentration favored free active chlorine (FAC) speciation into Cl2 and increased overall isothiazolinone removal. Regardless of the dominant FAC species, the elimination of MIT and CMIT resulted in an immediate loss of acute toxicity under all experimental conditions, which was attributed to a preferential attack at the S-atom resulting in subsequent formation of sulfoxides and sulfones and eventually an S-elimination. However, chlorination of isothiazolinone biocides in secondary effluent only achieved <10% elimination at typical disinfection chlorine exposure 200 mg·L-1·min, but was predicted to be remarkably increased by acidizing solution to pH 5.5. Alternative measures might be needed to minimize the discharge of these toxic chemicals into the aquatic environment.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Chlorine , Disinfectants/toxicity , Halogenation , Halogens , Humans , Hydrogen-Ion Concentration , Kinetics , Pandemics , Sulfones , Sulfoxides , Thiazoles , Wastewater , Water Pollutants, Chemical/analysis , Water Purification/methods
13.
Sci Total Environ ; 851(Pt 2): 158310, 2022 Dec 10.
Article in English | MEDLINE | ID: covidwho-2004487

ABSTRACT

The potential risk of SARS-CoV-2 in treated effluent from a wastewater treatment plant (WWTP) is concerned since SARS-CoV-2 is contained in wastewater during the COVID-19 outbreak. However, the removal of SARS-CoV-2 in WWTP has not been well investigated. The objectives of this study were (i) to clarify the removal performance of SARS-CoV-2 during wastewater treatment, (ii) to compare the removal performance of different secondary treatment processes, and (iii) to evaluate applicability of pepper mild mottle of virus (PMMoV) as a performance indicator for the reduction of SARS-CoV-2 RNA in wastewater treatment. Influent wastewater, secondary-treatment effluent (before chlorination), and final effluent (after chlorination) samples were collected from a WWTP from May 28 to September 24, 2020, during the COVID-19 outbreak in Japan. The target WWTP had three parallel treatment systems employing conventional activated sludge (CAS), anaerobic-anoxic -oxic (A2O), and membrane bioreactor (MBR) processes. SARS-CoV-2 in both the liquid and solid fractions of the influent wastewater was concentrated and quantified using RT-qPCR. SARS-CoV-2 in treated effluent was concentrated from 10 L samples to achieve a detection limit as low as 10 copies/L. The log reduction value (LRV) of SARS-CoV-2 was 2.7 ± 0.86 log10 in CAS, 1.6 ± 0.50 log10 in A2O, and 3.6 ± 0.62 log10 in MBR. The lowest LRV observed during the sampling period was 2.8 log10 in MBR, 1.2 log10 in CAS, and 1.0 log10 in A2O process, indicating that the MBR had the most stable reduction performance. PMMoV was found to be a good indicator virus to evaluate reduction performance of SARS-CoV-2 independent of the process configuration because the LRV of PMMoV was significantly lower than that of SARS-CoV-2 in the CAS, A2O and MBR processes.


Subject(s)
COVID-19 , Water Purification , Humans , Sewage , SARS-CoV-2 , Wastewater , Anaerobiosis , RNA, Viral , Bioreactors , Waste Disposal, Fluid
14.
Journal of Hazardous Materials Advances ; : 100121, 2022.
Article in English | ScienceDirect | ID: covidwho-1914424

ABSTRACT

Advanced wastewater treatment technologies are effective methods and currently attract growing attention, especially in arid and semi-arid areas, for reusing water, reducing water pollution, and explicitly declining, inactivating, or removing SARS-CoV-2. Overall, removing organic matter and micropollutants prior to wastewater reuse is critical, considering that water reclamation can help provide a crop irrigation system and domestic purified water. Advanced wastewater treatment processes are highly recommended for contaminants such as monovalent ions from an abiotic source and SARS-CoV-2 from an abiotic source. This work introduces the fundamental knowledge of various methods in advanced water treatment, including membranes, filtration, Ultraviolet (UV) irradiation, ozonation, chlorination, advanced oxidation processes, activated carbon (AC), and algae. Following that, an analysis of each process for organic matter removal and mitigation or prevention of SARS-CoV-2 contamination is discussed. Next, a comprehensive overview of recent advances and breakthroughs is provided for each technology. Finally, the advantages and disadvantages of each method are discussed.

15.
Environ Int ; 167: 107389, 2022 09.
Article in English | MEDLINE | ID: covidwho-1914334

ABSTRACT

Chlorination disinfection has been widely used to kill the pathogenic microorganisms in wastewater sludge during the special Covid-19 period, but sludge chlorination might cause the generation of harmful disinfection byproducts (DBPs). In this work, the transformation of extracellular polymeric substance (EPS) and mechanisms of Cl-DBPs generation during sludge disinfection by sodium hypochlorite (NaClO) were investigated using multispectral analysis in combination with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The microorganism Escherichia coli (E. coli) was effectively inactivated by active chlorine generated from NaClO. However, a high diversity of Cl-DBPs were produced with the addition of NaClO into sludge, causing the increase of acute toxicity on Q67 luminous bacteria of chlorinated EPS. A variety of N-containing molecular formulas were produced after chlorination, but N-containing DBPs were not detected, which might be the indicative of the dissociation of -NH2 groups after Cl-DBPs generated. Additionally, the release of N-containing compounds was increased in alkaline environment caused by NaClO addition, resulted in more Cl-DBPs generation via nucleophilic substitutions. Whereas, less N-compounds and Cl-DBPs were detected after EPS chlorination under acidic environment, leading to lower cell cytotoxicity. Therefore, N-containing compounds of lignin derivatives in sludge were the major Cl-DBPs precursors, and acidic environment could control the release of N-compounds by eliminating the dissociation of functional groups in lignin derivatives, consequently reducing the generation and cytotoxicity of Cl-DBPs. This study highlights the importance to control the alkalinity of sludge to reduce Cl-DBPs generation prior to chlorination disinfection process, and ensure the safety of subsequential disposal for wastewater sludge.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Disinfectants/toxicity , Disinfection/methods , Escherichia coli , Extracellular Polymeric Substance Matrix/chemistry , Halogenation , Humans , Lignin , Sewage , Wastewater/analysis , Water Pollutants, Chemical/analysis , Water Purification/methods
16.
14th International Conference on Security of Information and Networks, SIN 2021 ; 2021.
Article in English | Scopus | ID: covidwho-1784555

ABSTRACT

The rapid development of technology during the last decades has led to the integration of the network capabilities in the devices that are essential in the operation of Industrial Control Systems (ICS). Consequently, the attack surface of these assets has increased, putting at risk the nations that depend heavily on them for their continuity and functions. ICS physical and virtual testbeds are ideal platforms that can be used for cybersecurity research. Compared to physical testbeds, virtual testbeds are less expensive, safer to maintain, and more accessible, especially when access to research labs is restricted due to unforeseen circumstances such as COVID 19. Therefore, in this article, we propose VNWTS, a virtual water chlorination process for ICS cybersecurity analysis. VNWTS is composed of virtual components commonly found in physical ICS implementations. In addition, we implemented a set of attacks targeting the memory of the S7-1500 PLC and other VNWTS components such as level sensors, temperature sensors, and pumps. The results obtained from the experimentation phase show that the structure, configuration, and implementation of the VNWTS testbed can be used in ICS cybersecurity research. © 2021 IEEE.

17.
Int J Environ Res ; 16(1): 9, 2022.
Article in English | MEDLINE | ID: covidwho-1616321

ABSTRACT

Due to the prevalence of the COVID-19 outbreak, as well as findings of SARS-CoV-2 RNA in wastewater and the possibility of viral transmission through wastewater, disinfection is required. As a consequence, based on prior investigations, this work initially employed the viral concentration detection technique, followed by the RT-qPCR assay, as the foundation for identifying the SARS-CoV-2 virus in wastewater. After that, the ability and efficacy of chlorine, ozone, and UV disinfection to inactivate the SARS-CoV-2 virus from wastewater were examined. Chlorine disinfection is the most extensively used disinfection technology due to its multiple advantages. With a chlorine dioxide disinfectant dose of 40 mg/L, the SARS-CoV virus is inactivated after 30 min of contact time. On the other hand, ozone is a powerful oxidizer and an effective microbicide that is employed as a disinfectant due to its positive characteristics. After 30 min of exposure to 1000 ppmv ozone, corona pseudoviruses are reduced by 99%. Another common method of disinfection is using ultraviolet radiation, which is usually 253.7 nm suitable for ultraviolet disinfection. At a dose of 1048 mJ/cm2, UVC radiation completely inactivates the SARS-CoV-2 virus. Finally, to evaluate disinfection performance and optimize disinfection strategies to prevent the spread of SARS-CoV-2, this study attempted to investigate the ability to remove and compare the effectiveness of each disinfectant to inactive the SARS-CoV-2 virus from wastewater, summarize studies, and provide future solutions due to the limited availability of integrated resources in this field and the spread of the SARS-CoV-2 virus worldwide.

18.
Ergonomics ; 64(9): 1205-1216, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1177167

ABSTRACT

Changing gloves more frequently is encouraged, more now than ever given the COVID-19 pandemic. When the donning process has moisture introduced, however, complications can arise, which consumes vital time. Most commonly, gloves undergo a chlorination treatment to reduce glove tack, allowing easier donning. To assess the effects of different chlorination strengths and glove thicknesses on donning, acrylonitrile butadiene gloves were manufactured at two different thicknesses (0.05 and 0.10 mm) with 4 different chlorination treatments: 0, 500, 1000 and 2000 ppm. Six participants were used to assess the time taken to don each of the glove sets with dry and wet hands (16 tests in total). Overall, the thicker gloves took longer to don, due to differences in the material stiffness hindering the donning process. The quickest performance from the chlorinated gloves was noted in the 1000 and 2000 ppm concentrations. Wet conditions also showed significant increases in the donning time.Practitioners Summary: The study was conducted based on the gaps identified in previous literature reviews which revealed the requirement for a greater understanding of glove donning process. It was found a stronger chlorination was detrimental when the hands were wet, but better when dry. Thicker gloves were also found to be detrimental. Abbreviations: PPE: personal protective equipment; NBR: acrylonitrile butadiene rubber; NRL: natural rubber latex; EN: European standards; s: seconds; Ts: tensile strength; Fb: force at break; T: thickness; Eb: elongation at break; HSD: honest significant difference; FTIR: Fourier transform infrared; covid-19: coronavirus disease 2019.


Subject(s)
Gloves, Surgical , Halogenation , COVID-19 , Gloves, Surgical/classification , Hand , Humans , Pandemics , Water
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