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1.
Nat Rev Gastroenterol Hepatol ; 19(6): 350, 2022 06.
Article in English | MEDLINE | ID: covidwho-1873518
2.
Sci Total Environ ; 838(Pt 3): 156193, 2022 Sep 10.
Article in English | MEDLINE | ID: covidwho-1852053

ABSTRACT

During the COVID-19 pandemic, the use of chlorine-based disinfectants has surged due to their excellent performance and cost-effectiveness in intercepting the spread of the virus and bacteria in water and air. Many authorities have demanded strict chlorine dosage for disinfection to ensure sufficient chlorine residual for inactivating viruses and bacteria while not posing harmful effects to humans as well as the environment. Reliable chlorine sensing techniques have therefore become the keys to ensure a balance between chlorine disinfection efficiency and disinfection safety. Up to now, there is still a lack of comprehensive review that collates and appraises the recently available techniques from a practical point of view. In this work, we intend to present a detailed overview of the recent advances in monitoring chlorine in both dissolved and gaseous forms aiming to present valuable information in terms of method accuracy, sensitivity, stability, reliability, and applicability, which in turn guides future sensor development. Data on the analytical performance of different techniques and environmental impacts associated with the dominated chemical-based techniques are thus discussed. Finally, this study concludes with highlights of gaps in knowledge and trends for future chlorine sensing development. Due to the increasing use of chlorine in disinfection and chemical synthesis, we believe the information present in this review is a relevant and timely resource for the water treatment industry, healthcare sector, and environmental organizations.


Subject(s)
COVID-19 , Disinfectants , Water Purification , Bacteria , COVID-19/epidemiology , Chlorides , Chlorine , Disinfection/methods , Halogenation , Humans , Pandemics , Reproducibility of Results , Water Purification/methods
3.
Int J Mol Sci ; 23(6)2022 Mar 11.
Article in English | MEDLINE | ID: covidwho-1742489

ABSTRACT

The pandemic emergency determined by the spreading worldwide of the SARS-CoV-2 virus has focused the scientific and economic efforts of the pharmaceutical industry and governments on the possibility to fight the virus by genetic immunization. The genetic material must be delivered inside the cells by means of vectors. Due to the risk of adverse or immunogenic reaction or replication connected with the more efficient viral vectors, non-viral vectors are in many cases considered as a preferred strategy for gene delivery into eukaryotic cells. This paper is devoted to the evaluation of the gene delivery ability of new synthesized gemini bis-pyridinium surfactants with six methylene spacers, both hydrogenated and fluorinated, in comparison with compounds with spacers of different lengths, previously studied. Results from MTT proliferation assay, electrophoresis mobility shift assay (EMSA), transient transfection assay tests and atomic force microscopy (AFM) imaging confirm that pyridinium gemini surfactants could be a valuable tool for gene delivery purposes, but their performance is highly dependent on the spacer length and strictly related to their structure in solution. All the fluorinated compounds are unable to transfect RD-4 cells, if used alone, but they are all able to deliver a plasmid carrying an enhanced green fluorescent protein (EGFP) expression cassette, when co-formulated with 1,2-dioleyl-sn-glycero-3-phosphoethanolamine (DOPE) in a 1:2 ratio. The fluorinated compounds with spacers formed by six (FGP6) and eight carbon atoms (FGP8) give rise to a very interesting gene delivery activity, greater to that of the commercial reagent, when formulated with DOPE. The hydrogenated compound GP16_6 is unable to sufficiently compact the DNA, as shown by AFM images.


Subject(s)
DNA/genetics , Gene Transfer Techniques , Methane/chemistry , Pyridinium Compounds/chemistry , Surface-Active Agents/chemistry , Transfection/methods , A549 Cells , Cell Survival , DNA/chemistry , DNA/metabolism , Genetic Therapy/methods , Halogenation , Humans , Hydrogenation , Methane/metabolism , Microscopy, Atomic Force , Molecular Structure , Plasmids/chemistry , Plasmids/genetics , Plasmids/metabolism , Pyridinium Compounds/metabolism , Reproducibility of Results , Surface-Active Agents/metabolism
4.
Int J Mol Sci ; 23(4)2022 Feb 21.
Article in English | MEDLINE | ID: covidwho-1705083

ABSTRACT

We theoretically investigated the adsorption of two common anti-COVID drugs, favipiravir and chloroquine, on fluorinated C60 fullerene, decorated with metal ions Cr3+, Fe2+, Fe3+, Ni2+. We focused on the effect of fluoridation on the interaction of fullerene with metal ions and drugs in an aqueous solution. We considered three model systems, C60, C60F2 and C60F48, and represented pristine, low-fluorinated and high-fluorinated fullerenes, respectively. Adsorption energies, deformation of fullerene and drug molecules, frontier molecular orbitals and vibrational spectra were investigated in detail. We found that different drugs and different ions interacted differently with fluorinated fullerenes. Cr3+ and Fe2+ ions lead to the defluorination of low-fluorinated fullerenes. Favipiravir also leads to their defluorination with the formation of HF molecules. Therefore, fluorinated fullerenes are not suitable for the delivery of favipiravir and similar drugs molecules. In contrast, we found that fluorine enhances the adsorption of Ni2+ and Fe3+ ions on fullerene and their activity to chloroquine. Ni2+-decorated fluorinated fullerenes were found to be stable and suitable carriers for the loading of chloroquine. Clear shifts of infrared, ultraviolet and visible spectra can provide control over the loading of chloroquine on Ni2+-doped fluorinated fullerenes.


Subject(s)
Amides/chemistry , Antiviral Agents/chemistry , Chloroquine/chemistry , Fullerenes/chemistry , Metals/chemistry , Pyrazines/chemistry , COVID-19 , Density Functional Theory , Drug Carriers/chemistry , Drug Delivery Systems , Halogenation , Models, Molecular , Nickel/chemistry
5.
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
6.
J Hazard Mater ; 425: 128037, 2022 03 05.
Article in English | MEDLINE | ID: covidwho-1575585

ABSTRACT

High contents of heavy metals and Cl are major challenges for incineration residue disposal. Classification by the Chinese government and the coronavirus disease 2019 pandemic have changed the characteristics of incineration residues, thereby increasing the difficulty of disposal. In this study, medical waste incineration fly ash (MWI FA) was proposed as an additive to promote chlorination volatilization of heavy metals from municipal solid waste incineration fly ash (MSWI FA) and medical waste incineration slag (MWI S). When the mixing ratio of MWI FA to MSWI FA was 1:3, the chlorination volatilization efficiencies of Cu, Zn, Pb, and Cd at 1000 °C for 60 min were 50.2%, 99.4%, 99.7%, and 97.9%, respectively. When MWI FA was mixed with MWI S at a ratio of 1:1, the chlorination volatilization efficiencies of Cu, Zn, Pb, and Cd at 1200 °C for 40 min were 88.9%, 99.7%, 97.3%, and 100%, respectively. Adding MWI FA can replenish Cl in MSWI FA and MWI S while increasing the surface area and forming pore structures by sublimation of NaCl and decomposition of CaSO4, or can reduce the melting point and viscosity by Na2O destroying the glass matrix. Therefore, MWI FA can be co-disposed with MSWI FA and MWI S respectively to enhance the chlorination volatilization of heavy metals.


Subject(s)
COVID-19 , Medical Waste , Metals, Heavy , Refuse Disposal , Carbon , Coal Ash , Halogenation , Humans , Incineration , Metals, Heavy/analysis , Particulate Matter , SARS-CoV-2 , Solid Waste , Volatilization
7.
Molecules ; 26(20)2021 Oct 13.
Article in English | MEDLINE | ID: covidwho-1526851

ABSTRACT

There have been more than 150 million confirmed cases of SARS-CoV-2 since the beginning of the pandemic in 2019. By June 2021, the mortality from such infections approached 3.9 million people. Despite the availability of a number of vaccines which provide protection against this virus, the evolution of new viral variants, inconsistent availability of the vaccine around the world, and vaccine hesitancy, in some countries, makes it unreasonable to rely on mass vaccination alone to combat this pandemic. Consequently, much effort is directed to identifying potential antiviral treatments. Marine brominated tyrosine alkaloids are recognized to have antiviral potential. We test here the antiviral capacity of fourteen marine brominated tyrosine alkaloids against five different target proteins from SARS-CoV-2, including main protease (Mpro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H). These marine alkaloids, particularly the hexabrominated compound, fistularin-3, shows promising docking interactions with predicted binding affinities (S-score = -7.78, -7.65, -6.39, -6.28, -8.84 Kcal/mol) for the main protease (Mpro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H), respectively, where it forms better interactions with the protein pockets than the native interaction. It also shows promising molecular dynamics, pharmacokinetics, and toxicity profiles. As such, further exploration of the antiviral properties of fistularin-3 against SARS-CoV-2 is merited.


Subject(s)
Alkaloids/chemistry , SARS-CoV-2/metabolism , Alkaloids/isolation & purification , Alkaloids/therapeutic use , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/therapeutic use , Binding Sites , COVID-19/drug therapy , COVID-19/virology , Coronavirus 3C Proteases/chemistry , Coronavirus 3C Proteases/metabolism , Halogenation , Humans , Isoxazoles/chemistry , Isoxazoles/metabolism , Molecular Docking Simulation , Molecular Dynamics Simulation , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Structure-Activity Relationship , Tyrosine/analogs & derivatives , Tyrosine/chemistry , Tyrosine/metabolism
8.
Sci Total Environ ; 818: 151711, 2022 Apr 20.
Article in English | MEDLINE | ID: covidwho-1517467

ABSTRACT

The outbreak of COVID-19 has led to the large-scale usage of chlorinated disinfectants in cities. Disinfectants and disinfection by-products (DBPs) enter rivers through urban drainage and surface runoff. We investigated the variations in residual chlorine, DBPs, and different aquatic organisms in the Hanjiang, Fuhe, and Qinglinghe Rivers in Wuhan during the COVID-19 pandemic. The sampling sites were from the wastewater treatment plant outlets to the downstream drinking water treatment plant intakes. Total residual chlorine and DBPs (dichloromethane and trichloromethane) detected in the river water ranged from 0 to 0.84 mg/L and 0 to 0.034 mg/L, respectively. The residual chlorine and DBPs showed a gradual reduction pattern related to water flow, and the concentration at intakes did not exceed the Chinese drinking water source quality standards. Phytoplankton and zooplankton densities were not significantly correlated with residual chlorine and DBPs. The fluctuations in phytoplankton resource use efficiency (RUE) and zooplankton RUE in the Fuhe River, with the highest residual chlorine, and the Qinglinghe River with the highest DBPs, were higher than those in the Hanjiang River. For benthic macroinvertebrates, the number of functional feeding groups in the Hanjiang River was higher than that in the Fuhe and Qinglinghe Rivers. The water and sediment bacterial communities in the Hanjiang River differed significantly from those in the Fuhe and Qingling Rivers. The denitrification function involved in N metabolism was stronger in the Fuhe and Qinglinghe Rivers. Structural equation modelling revealed that residual chlorine and DBPs impacted the diversity of benthos through direct and indirect effects on plankton. Although large-scale chlorine-containing disinfectants use occurred during the investigation, it did not harm the density of the detected aquatic organisms in water sources. With the regular use of chlorinated disinfectants for indoor and outdoor environments in response to the SARS-CoV-2 globally, it is still necessary to study the long-term and accumulated responses of water ecosystems exposed to chlorine-containing disinfectants.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Aquatic Organisms , Chlorine , Cities , Disinfection , Ecosystem , Halogenation , Humans , Pandemics , SARS-CoV-2 , Water Pollutants, Chemical/analysis
9.
Molecules ; 26(22)2021 Nov 11.
Article in English | MEDLINE | ID: covidwho-1512513

ABSTRACT

The current COVID-19 outbreak has highlighted the need for the development of new vaccines and drugs to combat Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). Recently, various drugs have been proposed as potentially effective against COVID-19, such as remdesivir, infliximab and imatinib. Natural plants have been used as an alternative source of drugs for thousands of years, and some of them are effective for the treatment of various viral diseases. Emodin (1,3,8-trihydroxy-6-methylanthracene-9,10-dione) is a biologically active anthraquinone with antiviral activity that is found in various plants. We studied the selectivity of electrophilic aromatic substitution reactions on an emodin core (halogenation, nitration and sulfonation), which resulted in a library of emodin derivatives. The main aim of this work was to carry out an initial evaluation of the potential to improve the activity of emodin against human coronavirus NL63 (HCoV-NL63) and also to generate a set of initial SAR guidelines. We have prepared emodin derivatives which displayed significant anti-HCoV-NL63 activity. We observed that halogenation of emodin can improve its antiviral activity. The most active compound in this study was the iodinated emodin analogue E_3I, whose anti-HCoV-NL63 activity was comparable to that of remdesivir. Evaluation of the emodin analogues also revealed some unwanted toxicity to Vero cells. Since new synthetic routes are now available that allow modification of the emodin structure, it is reasonable to expect that analogues with significantly improved anti-HCoV-NL63 activity and lowered toxicity may thus be generated.


Subject(s)
Antiviral Agents/pharmacology , Coronavirus NL63, Human/drug effects , Emodin/analogs & derivatives , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Adenosine Monophosphate/therapeutic use , Alanine/analogs & derivatives , Alanine/pharmacology , Alanine/therapeutic use , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Cell Survival/drug effects , Chlorocebus aethiops , Coronavirus Infections/drug therapy , Coronavirus Infections/virology , Coronavirus NL63, Human/isolation & purification , Emodin/chemical synthesis , Halogenation , Humans , Vero Cells
10.
Sci Total Environ ; 811: 151409, 2022 Mar 10.
Article in English | MEDLINE | ID: covidwho-1500240

ABSTRACT

In this study, concentrations of disinfection byproducts (DBPs) and COVID-19 related pharmaceuticals in wastewater effluents and surface water were measured two weeks, three months and eight months after the lockdown in Wuhan. Little temporal variation in DBP concentrations suggested intensified disinfection during the COVID-19 pandemic had limited impacts on the occurrence of DBPs in the aquatic environment. In contrast, the pandemic led to a significant increase in concentrations of lopinavir and ritonavir in wastewater effluents and surface water. The high detection frequency of these pharmaceuticals in surface water after the lockdown highlighted their mobility and persistence in the aquatic environment. The initial ecological risk assessment indicated moderate risks associated with these pharmaceuticals in surface water. As the global situation is still rapidly evolving with a continuous surge in the number of confirmed COVID-19 cases, our results suggest a pressing need for monitoring COVID-19 related pharmaceuticals as well as a systematic evaluation of their ecotoxicities in the aquatic environment.


Subject(s)
COVID-19 , Disinfectants , Pharmaceutical Preparations , Water Pollutants, Chemical , Water Purification , Communicable Disease Control , Disinfection , Halogenation , Humans , Pandemics , SARS-CoV-2 , Water Pollutants, Chemical/analysis
11.
J Am Chem Soc ; 143(40): 16777-16785, 2021 10 13.
Article in English | MEDLINE | ID: covidwho-1442692

ABSTRACT

The most recent global health crisis caused by the SARS-CoV-2 outbreak and the alarming use of chemical warfare agents highlight the necessity to produce efficient protective clothing and masks against biohazard and chemical threats. However, the development of a multifunctional protective textile is still behind to supply adequate protection for the public. To tackle this challenge, we designed multifunctional and regenerable N-chlorine based biocidal and detoxifying textiles using a robust zirconium metal-organic framework (MOF), UiO-66-NH2, as a chlorine carrier which can be easily coated on textile fibers. A chlorine bleaching converted the amine groups located on the MOF linker to active N-chlorine structures. The fibrous composite exhibited rapid biocidal activity against both Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus) with up to a 7 log reduction within 5 min for each strain as well as a 5 log reduction of SARS-CoV-2 within 15 min. Moreover, the active chlorine loaded MOF/fiber composite selectively and rapidly degraded sulfur mustard and its chemical simulant 2-chloroethyl ethyl sulfide (CEES) with half-lives less than 3 minutes. The versatile MOF-based fibrous composite designed here has the potential to serve as protective cloth against both biological and chemical threats.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Chemical Warfare Agents/chemistry , Chlorine/pharmacology , Metal-Organic Frameworks/pharmacology , Protective Clothing , Animals , Anti-Bacterial Agents/chemical synthesis , Antiviral Agents/chemical synthesis , Cell Line , Chlorine/chemistry , Escherichia coli/drug effects , Halogenation , Humans , Metal-Organic Frameworks/chemical synthesis , Microbial Sensitivity Tests , Mustard Gas/analogs & derivatives , Mustard Gas/chemistry , Oxidation-Reduction , SARS-CoV-2/drug effects , Staphylococcus aureus/drug effects , Textiles , Zirconium/chemistry
12.
Molecules ; 26(19)2021 Sep 24.
Article in English | MEDLINE | ID: covidwho-1438673

ABSTRACT

We report the design and synthesis of a series of new 5-chloropyridinyl esters of salicylic acid, ibuprofen, indomethacin, and related aromatic carboxylic acids for evaluation against SARS-CoV-2 3CL protease enzyme. These ester derivatives were synthesized using EDC in the presence of DMAP to provide various esters in good to excellent yields. Compounds are stable and purified by silica gel chromatography and characterized using 1H-NMR, 13C-NMR, and mass spectral analysis. These synthetic derivatives were evaluated in our in vitro SARS-CoV-2 3CLpro inhibition assay using authentic SARS-CoV-2 3CLpro enzyme. Compounds were also evaluated in our in vitro antiviral assay using quantitative VeroE6 cell-based assay with RNAqPCR. A number of compounds exhibited potent SARS-CoV-2 3CLpro inhibitory activity and antiviral activity. Compound 9a was the most potent inhibitor, with an enzyme IC50 value of 160 nM. Compound 13b exhibited an enzyme IC50 value of 4.9 µM. However, it exhibited a potent antiviral EC50 value of 24 µM in VeroE6 cells. Remdesivir, an RdRp inhibitor, exhibited an antiviral EC50 value of 2.4 µM in the same assay. We assessed the mode of inhibition using mass spectral analysis which suggested the formation of a covalent bond with the enzyme. To obtain molecular insight, we have created a model of compound 9a bound to SARS-CoV-2 3CLpro in the active site.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , COVID-19/drug therapy , Coronavirus 3C Proteases/antagonists & inhibitors , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacology , SARS-CoV-2/drug effects , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Chlorocebus aethiops , Coronavirus 3C Proteases/metabolism , Esters/chemistry , Esters/pharmacology , Halogenation , Humans , Ibuprofen/analogs & derivatives , Ibuprofen/pharmacology , Indomethacin/analogs & derivatives , Indomethacin/pharmacology , Molecular Docking Simulation , Pyridines/chemistry , Pyridines/pharmacology , SARS-CoV-2/metabolism , Salicylic Acid/chemistry , Salicylic Acid/pharmacology , Vero Cells
13.
Sci Total Environ ; 798: 149320, 2021 Dec 01.
Article in English | MEDLINE | ID: covidwho-1330050

ABSTRACT

There has been a surge of interest in interfacial hypochlorous acid (HOCl) chemistry for indoor air quality and public health. Here we combined nanoelectrospray mass spectrometry (nESI-MS) and acoustic levitation (AL) techniques to study the chlorination chemistry of three model lipids (DPPE, POPG, DOPG) mediated by HOCl at the air-water interface of levitated water droplet. For DPPE with no CC double bonds, HOCl was insensitive to the alkane chains, and showed considerable delay directing to head amino groups compared to that in aqueous environment. Chlorination chemistry, for POPG and DOPG with CC double bonds, preferentially reacted with double bonds of one chain. The mechanism was discussed in light of these observations, and it is concluded that the increased hydrophilicity of the chlorinated chain disturbed the lipid packing and attracted it toward the water phase. In addition, the reaction rate constant and reactive uptake coefficient suggested that the chlorination of lipids exposed to HOCl at the air-water interface is likely to occur rapidly. These results gain the knowledge of HOCl mediated lipid interface reaction at the molecule level, and would better understand the adverse health effects associated with elevated indoor pollutants.


Subject(s)
Air Pollution, Indoor , Hypochlorous Acid , Halogenation , Lipids , Water
14.
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
15.
J Hazard Mater ; 418: 126249, 2021 09 15.
Article in English | MEDLINE | ID: covidwho-1244766

ABSTRACT

Intensified use of disinfectants to control COVID-19 could unintentionally increase the disinfection byproducts (DBPs) in the environment. In indoor spaces, it is critical to determine the optimal disinfection practice to prevent the spread of the virus while keeping DBPs at relatively low levels in the air. The formation of DBPs exceed 0.1 µg/mg while hypochlorite dosed at >10 mg/m3. The total DBP concentrations in highly disinfected places (100-200 mg/m3 hypochlorite) were as high as 66.8 µg/m3, and the Hazard Index (HI) was up to 0.84, and both values were much higher than those in less disinfected places (<10 mg/m3 hypochlorite). Taking into account the HI, formation yields and the origin of the DBPs, we recommended 10 mg/m3 as the suggested hypochlorite dose to minimize DBPs generation during routine disinfection for controlling the coronavirus. DBPs in indoor air could be eliminated by ventilation, reducing the usage of personal care products, and wiping the solid surface with water before or after disinfection. These results highlighted the necessity to control air-borne DBPs and their associated health risks arising from intensified disinfection, and will guide the further development of evidence-based regulation on DBP exposure during disinfection and improve public health protection.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Disinfection , Halogenation , Humans , Pandemics , SARS-CoV-2 , Water Pollutants, Chemical/analysis
16.
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
17.
Water Res ; 198: 117138, 2021 Jun 15.
Article in English | MEDLINE | ID: covidwho-1174530

ABSTRACT

Intensified sanitization practices during the recent coronavirus disease-2019 (COVID-19) led to the release of chlorine-based disinfectants in surface water, potentially triggering the formation of disinfection byproducts (DBPs) in the presence of dissolved organic nitrogen (DON). Thus, a comprehensive investigation of DON's spatial distribution and its association with DBP occurrence in the surface water is urgently needed. In this study, a total of 51 water samples were collected from two rivers and four lakes in May 2020 in Wuhan to explore the regional variation of nitrogen (N) species, DON's compositional characteristics, and the three classes of DBP occurrence. In lakes, 53.0% to 86.3% of N existed as DON, with its concentration varying between 0.3-4.0 mg N/L. In contrast, NO3--N was the dominant N species in rivers. Spectral analysis revealed that DON in the lakes contained higher humic and fulvic materials with higher A254, A253/A203, SUVA254, and PIII+IV/PI+II+V ratios, while rivers had higher levels of hydrophilic compounds. Trihalomethanes (THMs) were the most prevalent DBPs in the surface waters, followed by N-nitrosamines and haloacetonitriles (HANs). The levels of N-nitrosamines (23.1-97.4 ng/L) increased significantly after the outbreak of the COVID-19 pandemic. Excessive DON in the surface waters was responsible for the formation of N-nitrosamines. This study confirmed that the presence of DON in surface water could result in DBP formation, especially N-nitrosamines, when disinfectants were discharged into surface water during the COVID-19 pandemic.


Subject(s)
COVID-19 , Disinfectants , Water Pollutants, Chemical , Water Purification , Disinfection , Halogenation , Humans , Nitrogen/analysis , Pandemics , SARS-CoV-2 , Trihalomethanes/analysis , Water Pollutants, Chemical/analysis
18.
Eur J Med Chem ; 209: 112884, 2021 Jan 01.
Article in English | MEDLINE | ID: covidwho-800277

ABSTRACT

A novel methodology to access alkynyl nucleoside analogues is elaborated. Highly fluorescent 5-alkynylfuropyrimidines were synthesized (97-46%) and their antiviral properties investigated in vitro. Regiochemistry of the functionalization was achieved with the aid of 5-endo-dig electrophilic halocyclization of acetyl 5-p-tolyl- or 5-p-pentylphenyl-2'-deoxyuridine. Structure of one of the resulting nucleosides, 6-p-tolyl-5-iodo-2'-deoxyribofuranosyl-furo[2,3-d]pyrimidin-2-one, was confirmed by X-ray crystallography, and its conformation was compared to related nucleosides. Diverse alkynyl substituents were introduced at the heterobicyclic base C-5 position via Sonogashira coupling of 5-iodo-2'-deoxyribofuranosyl-furo[2,3-d]pyrimidin-2-ones. The resulting compounds had fluorescence emissions of 452-481 nm. High quantum yields of 0.53-0.60 were observed for 9-ethynyl-9-fluorenol and propargyl alcohol/methyl ether-modified furopyrimidines. These modified nucleosides, designed in the form of ribose acetyl esters, are potential tools for fluorescent tagging, studying nucleoside metabolism, 2'-deoxyribonucleoside kinase activity, and antiviral activity. Antiviral assays against a broad spectrum of DNA and RNA viruses showed that in human embryonic lung (HEL) cell cultures some of the compounds posess antiviral activity (EC50 1.3-13.2 µM) against varicella-zoster virus (VZV). The alkynyl furopyrimidine with two p-pentylphenyl substituents emerged as the best compound with reasonable and selective anti-VZV activity, confirming p-pentylphenyl potency as a pharmacophore.


Subject(s)
Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Pyrimidine Nucleosides/chemistry , Pyrimidine Nucleosides/pharmacology , Antiviral Agents/chemical synthesis , Cell Line , Fluorescence , Halogenation , Herpesvirus 3, Human/drug effects , Humans , Models, Molecular , Pyrimidine Nucleosides/chemical synthesis , Varicella Zoster Virus Infection/drug therapy , Varicella Zoster Virus Infection/virology
19.
Horm Metab Res ; 52(7): 540-546, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-618763

ABSTRACT

The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic affects people around the world. However, there have been striking differences in the number of infected individuals and deaths in different countries. Particularly, within Central Europe in countries that are similar in ethnicity, age, and medical standards and have performed similar steps of containment, such differences in mortality rates remain inexplicable. We suggest to consider and explore environmental factors to explain these intriguing variations. Countries like Northern Italy, France, Spain, and UK have suffered from 5 times more deaths from the corona virus infection than neighboring countries like Germany, Switzerland, Austria, and Denmark related to the size of their respective populations. There is a striking correlation between the level of environmental pollutants including pesticides, dioxins, and air pollution such as NO2 known to affect immune function and healthy metabolism with the rate of mortality in COVID-19 pandemic in these European countries. There is also a correlation with the use of chlorination of drinking water in these regions. In addition to the improvement of environmental protective programs, there are possibilities to lower the blood levels of these pollutants by therapeutic apheresis. Furthermore, therapeutic apheresis might be an effective method to improve metabolic inflammation, altered vascular perfusion, and neurodegeneration observed as long-term complications of COVID-19 disease.


Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/metabolism , Environment , Environmental Pollution/adverse effects , Halogenation , Metabolism , Pneumonia, Viral/epidemiology , Pneumonia, Viral/metabolism , Water Supply , COVID-19 , Disease Susceptibility , Humans , Pandemics
20.
Infect Dis Health ; 25(3): 186-193, 2020 08.
Article in English | MEDLINE | ID: covidwho-232539

ABSTRACT

BACKGROUND: Nosocomial pathogens are transmitted by contamination of surfaces causing healthcare-associated infections (HAI). The impact of locally produced disinfectant with operational training as a means to improve hygiene in resource-limited healthcare facilities and prevent HAI was evaluated. METHOD: In Burkina Faso, 4 types of electro-chlorinator devices that convert salt and water into sodium hypochlorite through electrolysis were installed in 26 healthcare facilities distributed across 3 sanitary districts. The program was evaluated at 4 months and 11 months and performance compared with a control group. RESULTS: After 11 months, over 90% of the facilities applied 8 of the 11 essential hygiene practices defined by the Ministry of Health, compared to 20% in the control group. 61.5% of the healthcare facilities improved the chlorine concentration of their sodium hypochlorite solutions, reaching an average concentration of 5.1 g/L compared to an average of 2.1 g/L in the control group. Additionally, a cost-benefit analysis demonstrated that locally produced sodium hypochlorite led to daily savings ranging between 2.7 and 53 euros depending on the device compared with the purchase of chlorine tablets. CONCLUSION: Results, therefore, suggest that electro-chlorinator devices in addition to hygiene sensitization can be a simple, cost-effective and tailored intervention to reduce the prevalence of HAI in low-resource settings.


Subject(s)
Cross Infection/prevention & control , Disinfectants/pharmacology , Hygiene , Sodium Hypochlorite/pharmacology , Burkina Faso/epidemiology , Cross Infection/epidemiology , Electrolysis , Halogenation , Health Facilities , Humans
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