****!!!!***!!!!***!!!!** "Spike protein was first mixed with various concentrations of CD... at room temperature for 5 min." "CD at 0.25 mmol/L or 0.5 mmol/L was effective in inactivating the binding of the spike protein to ACE2.. However, CD was not effective at 0.1 mmol/L concentration. The result strongly suggests that CD in sufficient cnocentration is effective in inactivating the spike protein of SARS-CoV-2 coronavirus and thus preventing its binding to human cells."

"The reaction rates increase greatly with pH to give a series of oxidized products."

{Need clarification on why PFA is specified as more widely applicable disinfectant than chlorine dioxide?} "We studied the toxicity of the alternative disinfectants peracetic acid (PAA), performic acid (PFA) and chlorine dioxide (ClO2) and their degradation products hydrogen peroxide (H2O2) and chlorite (ClO2-) on Vibrio fischeri and Daphnia magna. ClO2 was more toxic to D. magna (EC50 < 0.09 mg/L) and PFA was most toxic to V. fischeri (EC50 0.24 mg/L). EC50 of PFA, PAA, ClO2, H2O2 and ClO2- on D. magna were 0.85, 0.78,

Pre-oxidation is commonly used to mitigate the formation of byproducts during post-disinfection. A comparative study of the impact of four pre-oxidants, ozone (O3), chlorine dioxide (ClO2), permanganate (Mn(vii)) and ferrate (Fe(vi)), on the formation of trihalomethanes (THMs), haloacetonitriles (HANs) and a

****!!!!**** "we challenged the hypothesis that ClO2 decreases the viral load and virus-induced mortality in a vertebrate model. For this, we determined viral load, virus-induced lesions and mortality in 10-day old chick embryos" " viral titres were 2.4-fold lower and mortality was reduced by half in infected embryos that were treated with ClO2." " Lesions typical of IBV infections were observed in all inoculated embryos, but severity tended to be significantly lower in ClO2-treated embryos. We found no gross or microscopic evidence of toxicity caused by ClO2 at the doses used herein. Our study shows that ClO2 could be a safe and viable way of treating and mitigating the effects of avian coronavirus infections, and raises the possibility that similar effects could be observed in other organisms." The authors have declared no competing interest.

To maintain the high quality of potable water chlorine based disinfectants are frequently dosed into the drinking water network. Considering the oxidative nature of these species their long-term impact on the aging of polyolefin pipes is a matter of...

**** {Tested at 1 ppm and ph of 7 for 8 wks} "four different kinds of water pipes, two based on plastics, namely random polypropylene (PPR) and polyethylene of raised temperature (PERT/aluminum multilayer), and two made of metals, i.e., copper and galvanized steel, were put in a semi-closed system where ClO2 was dosed continuously. The semi-closed system allowed for the simulation of real ClO2 concentrations in common water distribution systems and to simulate the presence of pipes made with different materials from the source of water to the tap. Results show that ClO2 has a deep effect on all the materials tested (plastics and metals) and that severe damage occurs due to its strong oxidizing power in terms of surface chemical modification of metals and progressive cracking of plastics. These phenomena could in turn become an issue for the health and safety of drinking water due to progressive leakage of degraded products in the water."

****!!!!**** "The inactivation of virus and the inhibition of specific attachment both increased with increasing pH and increasing disinfectant concentration." "Inactivation of f2 was hypothesized to occur as the result of chlorine dioxide reacting with discrete chemical moieties in the viral protein. Cysteine, tyrosine and tryptophan reacted with chlorine dioxide within a time frame that could affect viral inactivation. In denatured f2 capsid protein monomers, these amino acids were almost totally degraded within 2 min by chlorine dioxide. Only tyrosine reacted with chlorine dioxide following treatment of the intact virion with disinfectant. Even though the degradation of tyrosine residues occurred at a much slower rate than the rate of virus inactivation, the protein component of f2 virus appeared to be the site of the lethal lesion produced by chlorine dioxide. These tyrosine reactions with chlorine dioxide appeared to alter the virus such that specific attachment was inhibited."

2005

"Currently, sodium chlorite is used on a large scale in the health care institutions worldwide as sodium chlorite solution is given to the patients affected by coronavirus for gargling. Moreover, sodium chlorite is also used as a disinfectant to sanitize the hospital surfaces. Due to the above mentioned reasons the demand for sodium chlorite is predicted to grow amidst the COVID-19 crisis."

"However, when chlorine dioxide generated by a gas generator typified by such a device is absorbed into water and used as a solution, it is unstable and cannot be decomposed in a short time to be useful for practical use. Here, chlorine dioxide generated in recent years is absorbed into an aqueous alkali solution (for example, an aqueous sodium percarbonate solution) and stabilized."

****!!!!**** List of chlorine dioxide generation companies, manufacturers and suppliers worldwide

"PURATE is the best total cost... PURATE technology is sodium ****chlorate**** based, as compared to sodium chlorite, like competing processes. Why does that matter? Sodium chlorite producers make sodium chlorite from sodium chlorate. It involves an expensive process of producing ClO2 and then converting to sodium chlorite so that it can be reconverted to ClO2 at the users site. We simply produces the ClO2 on site from sodium chlorate"

{Excellent chart of industrial uses} {Info on regulations for chlorine dioxide} "OxyChem technical sodium chlorite products"

****** "The most common method of generating ClO2 is through the reaction of chlorine gas with a solution of sodium chlorite. Theoretically, 1 lb of chlorine gas is required for each 2.6 lb of sodium chlorite. However, an excess of chlorine is often used to lower the pH to the required minimum of 3.5 and to drive the reaction to completion. Sodium hypochlorite can be used in place of the gaseous chlorine to generate chlorine dioxide. This process requires the addition of sulfuric or hydrochloric acid for pH control. Other methods used for chlorine dioxide generation include:..." "Complex organic molecules and ammonia are traditional chlorine-demand materials that do not react with chlorine dioxide. " "The chemical behavior and oxidation characteristics of aqueous chlorine dioxide are not well understood because of the difficulty in differentiating aqueous chlorine-containing species." "Chlorine dioxide consumed in water treatment reactions reverts to chlorite ions (ClO2-), chlorate ions (ClO3- ), and chloride ions (Cl -)." "As a gas, chlorine dioxide is more irritating and toxic than chlorine. Chlorine dioxide in air is detectable by odor at 14-17 ppm, irritating at 45 ppm, fatal in 44 min at 150 ppm, and rapidly fatal at 350 ppm. Concentrations greater than 14% in air can sustain a decomposition wave set off by an electric spark. The most common precursor for on-site generation of chlorine dioxide is also a hazardous material: liquid sodium chlorite. If allowed to dry, this powerful oxidizing agent forms a powdered residue that can ignite or explode if contacted by oxidizable materials. The hazardous nature of chlorine dioxide vapor and its precursor, and the volatility of aqueous solutions of chlorine dioxide, require caution in the design and operation of solution and feeding equipment."

"Calf feeding equipment... PRIOR TO USE, SANITIZE WITH THE OXYMER™ CLO2 @ 50 PPM RESIDUAL (2.5OZ/ GALLON OF WATER). WAIT 5 MINUTES BEFORE USING AND DO NOT DRY PRIOR TO USE. USE HIGH RANGE TEST STRIPS (0-500 PPM) TO VERIFY."

{Helpful basic orientation info on chlorine dioxide}

"Provided herein are methods of using a gas containing chlorine dioxide, or a liquid solution of chlorine dioxide, for reducing or eliminating a biological contaminant (e.g., an infectious biological contaminant, e.g., influenza, e.g., avian flu or swine flu) from a contaminated material (e.g., an agricultural material, e.g., a carcass, feed, bedding, and/or soil)."

{Links to many useful articles}

"An interesting feature of the reactions in acid solution is that chlorine dioxide is frequently a product. Although not a stable end-product, it persists for long periods of time; both the rate at which it disproportionates and the rate at which it reacts with chlorine in other oxidation states in acid at room temperatures are slow. Chlorine dioxide appears in the disproportionation of chlorate in acid, in the reduction of chlorate by chloride ion, the oxidation of chlorite by chlorine or hypochlorous acid and the disproportionation of chlorite in acid."

**** {This version of article includes very useful info on stabilized chlorine dioxide} "A range of commercially available oral rinse formulations contain the active agent sodiu m chlorite (Na+/ClO2−), which is com monly referred to as ‘ stabilised’ chlorine dioxide (ClO2●). ClO2−can be converted to active ClO2● by lower-ing the pH value of aqueous solutions containing the formeragent, a process which involves its prior protonation to form unstable chlorous acid (the pKav alue for this transformation is 2.31), which then decomposes to form ClO2● (stoichio-metrically, 0.50 of a molar equivalent of this free radical..."

D

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****!!!!****!!!!*** (2020) "ClO2 gas is easy decomposed under sun light so there is little tendency to form organochlorine by-products (Karsa, 2007)."

1999

"This book reports on the research done to determine whether East Bay Municipal Utility District, CA, can replace Cl2 with ClO2 for biofouling suppression in the aqueduct and in open-air treatment basins, with the aim of reducing THM and HAA concentrations without sacrificing treatment performance associated with the use of Cl2. "