Chemical & Biological Dynamics

Chemical & Biological Dynamics

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How Toxic Are Your Household Cleaning Supplies?
How Toxic Are Your Household Cleaning Supplies?
"Some all-purpose cleaners contain the sudsing agents diethanolamine (DEA) and triethanolamine (TEA). When these substances come into contact with nitrites, often present as undisclosed preservatives or contaminants, they react to form nitrosamines - carcinogens that readily penetrate the skin. 1,4-dioxane, another suspected carcinogen, may be present in cleaners made with ethoxylated alcohols. Butyl cellosolve (also known as ethylene glycol monobutyl ether), which may be neurotoxic (or cause damage to the brain and nervous system), is also present in some cleaners." "Alkylphenol ethoxylates (APEs)... are suspected hormone disruptors that don't readily biodegrade, threatening fish and wildlife when they go down your drain. And triclosan, the active ingredient in most antibacterial soaps, was detected in 57.6% of stream water samples from across the U.S." "U.S. Geological Survey found persistent detergent metabolites in 69% of streams tested. Sixty-six percent contained disinfectants." "Aerosol sprays produce tiny droplets that are easily inhaled and absorbed into the body, and their propellants, usually butane and propane, are flammable."
·organicconsumers.org·
How Toxic Are Your Household Cleaning Supplies?
Chlorine Dioxide -Versatile, High-Value Sterilant for the Biopharmaceutical Industry
Chlorine Dioxide -Versatile, High-Value Sterilant for the Biopharmaceutical Industry
Preliminary tests indicates that CD at low concentrations has valuable effects. As the industry becomes more familiar with CD, it could become an attractive choice for many operational sanitization, disinfection, and sterilization applications in biopharmaceutical manufacturing.
·clordisys.com·
Chlorine Dioxide -Versatile, High-Value Sterilant for the Biopharmaceutical Industry
Inactivation of human and simian rotaviruses by chlorine dioxide.
Inactivation of human and simian rotaviruses by chlorine dioxide.
The inactivation of single-particle stocks of human (type 2, Wa) and simian (SA-11) rotaviruses by chlorine dioxide was investigated. Experiments were conducted at 4 degrees C in a standard phosphate-carbonate buffer. Both virus types were rapidly inactivated, within 20 s under alkaline conditions, when chlorine dioxide concentrations ranging from 0.05 to 0.2 mg/liter were used. Similar reductions of 10(5)-fold in infectivity required additional exposure time of 120 s at 0.2 mg/liter for Wa and at 0.5 mg/liter for SA-11, respectively, at pH 6.0. The inactivation of both virus types was moderate at neutral pH, and the sensitivities to chlorine dioxide were similar. The observed enhancement of virucidal efficiency with increasing pH was contrary to earlier findings with chlorine- and ozone-treated rotavirus particles, where efficiencies decreased with increasing alkalinity
·aem.asm.org·
Inactivation of human and simian rotaviruses by chlorine dioxide.
Evaluation of the Antiviral Activity of Chlorine Dioxide and Sodium Hypochlorite against Feline Cilicivirus, Human Influenza Virus, Measles Virus, Danine Distemper, Human Herpesvirus, Human Adenovirus, Canine Adenovirus and Canine Parvovirus
Evaluation of the Antiviral Activity of Chlorine Dioxide and Sodium Hypochlorite against Feline Cilicivirus, Human Influenza Virus, Measles Virus, Danine Distemper, Human Herpesvirus, Human Adenovirus, Canine Adenovirus and Canine Parvovirus
We evaluated the antiviral activity of a chlorine dioxide gas solution (CD) and sodium hypochlorite (SH) against feline calicivirus, human influenza virus, measles virus, canine distemper virus, human herpesvirus, human adenovirus, canine adenovirus and canine parvovirus. CD at concentrations ranging from 1 to 100 ppm produced potent antiviral activity, inactivating >or= 99.9% of the viruses with a 15 sec treatment for sensitization. The antiviral activity of CD was approximately 10 times higher than that of SH.
·www.jstage.jst.go.jp·
Evaluation of the Antiviral Activity of Chlorine Dioxide and Sodium Hypochlorite against Feline Cilicivirus, Human Influenza Virus, Measles Virus, Danine Distemper, Human Herpesvirus, Human Adenovirus, Canine Adenovirus and Canine Parvovirus
Overall view of ClO2 by Howard Alliger (Frontier Pharmaceutical)
Overall view of ClO2 by Howard Alliger (Frontier Pharmaceutical)
****!!!!**** "The method of chlorine dioxide bacterial kill at low ppm concentration seems to occur by the disruption of protein synthesis and enzyme inactivation.48 49 This is similar to the "time honored", non-toxic mechanism of some common antibiotics. Oxidation of RNA and DNA do not appear to take place, or are at least unimportant in the process. The site of action lies in the soluble fraction of the cell and there appears to be no damage to whole structural components such as ribosomes" "At high ClO2 ppm, the method of rapid bacterial and viral kill appears to be the softening and destroying of the cell wall or viral capsid.52 Human cells do not have similar cell walls and are apparently unaffected. Our skin and bodies are likely protected from the general oxidative effects of ClO2 by the many reducing agents in our cells and blood, such as catalase, glutathione, superoxide dismutase, vitamins E, C, A, B complex, uric acid, zinc and selenium. This is probably the same internal protective mechanism that prevents damage from oxygen and free radicals. Bacteria and viruses do not contain most of these reducing compounds. Because ClO2 is a strong oxidizing agent and also itself a free radical, it quickly neutralizes reactive molecules,such as ****cytokines**** and oxygen free-radicals such as NO•, O2¯, H2O2, HClO, and OH •that are produced in the body by macrophages. These oxygen compounds are released in response to stress or infection and cause inflammation and pain. Other potential irritants found in wounds are similarly oxidized or reduced, such as leukotrienes, TNF, and interleukin. This neutralizing property of ClO2, combined with its ability to completely disinfect, makes IOXIDERM and DIOXIGUARD ideal wound medications. Unlike iodine compounds, or chlorhexidine, healing is not impeded.53 54 Veterinarians have been treating deep wounds and abscesses on tigers and elephants as well as dogs and cats with outstanding success.55 DIOXIDERM GEL had similar striking results on human (otherwise non-healing) diabetic ulcers." "The NOAEL, from animal ingestion studies involving ClO2 and ClO2 ̄, ranges to 100 ppmv[???] about the concentration of Frontier's DioxiDerm gel for topical use. . Water solutions of ClO2 will remain stable for several months if stored in a glass or PET bottle. “Stabilized” chlorine dioxide, which is a buffered solution ofsodium chlorite, does not release ClO2 until the pH of the solution is brought below 3." "Many nutrition and toxicology studies have been performed assessing chlorine dioxide's effect on flour. Treatment of flour with 200 ppm, fed to rats, had no effect after several generations.24,25 Flour treated with up to 500 ppm (5 times the concentration in DioxiCure Gel) fed to puppies had no untoward effect.26 Thirteen human subjects fed experimentally for six weeks with flour products that were treated with doses up to 400 ppm had no detectable toxic symptoms.27 Flour bleached with normal dosage is not reduced appreciably in nutritive value.28 Essential fatty acids are generally not effected, but tocopherol and cystine are oxidized." "hippuric acid, cinnamic acid, betaine, creatine, alanine, phenylalanine, valine, leucine, asparaginic acid, asparagine, glutaminic acid, serine, hydroxyproline, taurine, ... HO groups in alcohols and HO acids"
·cdn.shopify.com·
Overall view of ClO2 by Howard Alliger (Frontier Pharmaceutical)
Antimicrobial resistance of biofilms in medical devices
Antimicrobial resistance of biofilms in medical devices
Biofilm formation is a strategy by which microorganisms survive and adapt to the involving environment, particularly adverse conditions. The developme…
·sciencedirect.com·
Antimicrobial resistance of biofilms in medical devices
Virucidal efficacy of physico-chemical treatments against coronaviruses and parvoviruses of laboratory animals - PubMed
Virucidal efficacy of physico-chemical treatments against coronaviruses and parvoviruses of laboratory animals - PubMed
{Includes Sodium Chlorite} 1988. Virucidal efficacy of chemical disinfectants, heating and ultraviolet radiation against mouse hepatitis virus (MHV), canine coronavirus (CCV), Kilham rat virus (KRV) and canine parvovirus (CPV) were examined. Coronaviruses (MHV and CCV) were inactivated by ethanol, isopropanol, benzalkonium chloride …
·pubmed.ncbi.nlm.nih.gov·
Virucidal efficacy of physico-chemical treatments against coronaviruses and parvoviruses of laboratory animals - PubMed
Biocides and Novel Antimicrobial Agents for the Mitigation of Coronaviruses
Biocides and Novel Antimicrobial Agents for the Mitigation of Coronaviruses
***"The use of biocides effective against SARS-CoV-2 in toilet bowls apart from cleaning could be considered." Lists chlorine dioxide as effective against coronaviruses for disinfecting fomites and air. *Mentions that CD was reported as less effective than Chlorine against SARS-CoV-1 in some conditions.*
·europepmc.org·
Biocides and Novel Antimicrobial Agents for the Mitigation of Coronaviruses
Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-)
Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-)
The five investigated chemicals decreased in toxicity in the order chlorine dioxide, performic acid, peracetic acid, chlorite and hydrogen peroxide. The stability of the chemicals increased in the same order as the toxicity decrease. This indicates that even though ClO2 has the highest environmental hazard potential, it may still be suitable as an alternative disinfectant due to its rapid degradation in water.
·orbit.dtu.dk·
Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-)
USING CHLORINE DIOXIDE FOR TRIHALOMETHANE CONTROL | Science Inventory | US EPA
USING CHLORINE DIOXIDE FOR TRIHALOMETHANE CONTROL | Science Inventory | US EPA
Because of the November 1979 amendment to the National Interim Primary Drinking Water Regulations, many utilities were faced with changing their disinfection practices to comply with the 0.10-mg/L maximum contaminant level for trihalomethanes (THMs). After considering various options, one utility, the Evansville (Ind.) Water and Sewer Utility, chose chlorine dioxide disinfection as the most feasible method for controlling THMs. The performance of a 100-gpm (6.3-L/s) pilot plant that incorporated chlorine dioxide was so effective for reducing THMs that it has been used in Evansville's full-s...
·cfpub.epa.gov·
USING CHLORINE DIOXIDE FOR TRIHALOMETHANE CONTROL | Science Inventory | US EPA
Chlorite formation during ClO2 oxidation of model compounds having various functional groups and humic substances. | Semantic Scholar
Chlorite formation during ClO2 oxidation of model compounds having various functional groups and humic substances. | Semantic Scholar
" this study investigated the reactions of ClO2 with 30 model compounds, 10 humic substances and 2 surface waters. ClO2- yields were found to be dependent on the distribution of functional groups. ClO2 oxidation of amines, di- and tri-hydroxybenzenes at pH 7.0 had ClO2- yields 50%, while oxidation of olefins, thiols and benzoquinones had ClO2- yields..."
·semanticscholar.org·
Chlorite formation during ClO2 oxidation of model compounds having various functional groups and humic substances. | Semantic Scholar
Impact of ClO 2 pre-oxidation on the formation of CX 3 R-type DBPs from tyrosine-based amino acid precursors during chlorination and chloramination - PubMed
Impact of ClO 2 pre-oxidation on the formation of CX 3 R-type DBPs from tyrosine-based amino acid precursors during chlorination and chloramination - PubMed
ClO2 is frequently used as a pre-oxidant in water treatment plants. However, the effects of ClO2 pre-oxidation on disinfection by-product (DBP) formation, especially the highly toxic nitrogenous DBPs, during subsequent chlor(am)ination have not been studied thoroughly... Results imply that ClO2 is probably more suitable for use in combination with chloramination disinfection, rather than chlorination, in the integrated control of CX3R-type DBPs from source waters abundant in AAs.
·pubmed.ncbi.nlm.nih.gov·
Impact of ClO 2 pre-oxidation on the formation of CX 3 R-type DBPs from tyrosine-based amino acid precursors during chlorination and chloramination - PubMed
ClO 2 pre-oxidation changes the yields and formation pathways of chloroform and chloral hydrate from phenolic precursors during chlorination - PubMed
ClO 2 pre-oxidation changes the yields and formation pathways of chloroform and chloral hydrate from phenolic precursors during chlorination - PubMed
Phenolic moieties in natural organic matter (NOM) are important precursors of disinfection by-products (DBPs). In this study, the formation of chloral hydrate from chlorination of seventeen phenolic compounds, including mono-, di- and tri-hydroxybenzenes, were evaluated and the role of chlorine diox …
·pubmed.ncbi.nlm.nih.gov·
ClO 2 pre-oxidation changes the yields and formation pathways of chloroform and chloral hydrate from phenolic precursors during chlorination - PubMed
In Situ Formation of ***Free Chlorine*** During ClO2 [water] Treatment: Implications on the Formation of Disinfection Byproducts
In Situ Formation of ***Free Chlorine*** During ClO2 [water] Treatment: Implications on the Formation of Disinfection Byproducts
Chlorine dioxide (ClO2) is commonly used as an alternative disinfectant to chlorine in drinking water treatment because it produces limited concentrations of halogenated organic disinfection byproducts. During drinking water treatment, the primary ClO2 byproducts are the chlorite (50–70%) and the chlorate ions (0–30%). However, a significant portion of the ClO2 remains unaccounted for. This study demonstrates that when ClO2 was reacting with phenol, one mole of free available chlorine (FAC) was produced per two moles of consumed ClO2. The in situ formed FAC completed the mass balance on Cl for inorganic ClO2 byproducts (FAC + ClO2— + ClO3—). When reacting with organic matter extracts at near neutral conditions (pH 6.5–8.1), ClO2 also yielded a significant amount of FAC (up to 25%). Up to 27% of this in situ formed FAC was incorporated in organic matter forming adsorbable organic chlorine, which accounted for up to 7% of the initial ClO2 dose. Only low concentrations of regulated trihalomethanes were produced because of an efficient mitigation of their precursors by ClO2 oxidation. Conversely, dichloroacetonitrile formation from ClO2-induced generation of FAC was higher than from addition of FAC in absence of ClO2.
·pubs.acs.org·
In Situ Formation of ***Free Chlorine*** During ClO2 [water] Treatment: Implications on the Formation of Disinfection Byproducts
Chlorine Dioxide—Pollutant Transformation and Formation of Hypochlorous Acid as a Secondary Oxidant
Chlorine Dioxide—Pollutant Transformation and Formation of Hypochlorous Acid as a Secondary Oxidant
Chlorine dioxide (ClO2) has been used as a disinfectant in water treatment for a long time, and its use for micropollutant abatement in wastewater has recently been suggested. Surprisingly, a mechanistic understanding of ClO2 reactions in (waste)water matrices is largely lacking. The present study contributes to this mechanistic understanding by performing a detailed investigation of ClO2 reactions with organic matter using phenol as a surrogate for reactive phenolic moieties. A concept for indirectly determining HOCl using 2- and 4-bromophenol was developed. The reaction of phenol with ClO2 formed chlorite (62 ± 4% per ClO2 consumed) and hypochlorous acid (HOCl) (42 ± 3% per ClO2 consumed). The addition of ClO2 to wastewater (5 × 10–5 M ClO2) resulted in 40% atenolol and 47% metoprolol transformation. The presence of the selective HOCl scavenger glycine largely diminished their transformation, indicating that atenolol and metoprolol were transformed by a fast reaction with HOCl (e.g., k (atenolol + HOCl) = 3.5 × 104 M–1 s–1) that formed in ClO2 reactions with the wastewater matrix. The formation of HOCl may thus increase the number of transformable micropollutants in ClO2 applications. However, chlorine related byproducts may also be formed.
·pubs.acs.org·
Chlorine Dioxide—Pollutant Transformation and Formation of Hypochlorous Acid as a Secondary Oxidant
PurTabs ~Earthsafe
PurTabs ~Earthsafe
Comparison between NaDCC, sodium hypochlorite, and Peracetic acid (PAA)
·evaclean.com·
PurTabs ~Earthsafe
[Virucidal efficacy of eight disinfectants against pneumovirus, coronavirus and parvovirus] - PubMed
[Virucidal efficacy of eight disinfectants against pneumovirus, coronavirus and parvovirus] - PubMed
The virucidal activity of 8 disinfectants was analyzed towards 3 groups of viruses responsible for diseases in animals (pneumovirus, coronavirus, parvovirus). Whether organic matter is present or not, parvoviruses are the most resistant, since concentrations of disinfectants 20-500 times higher than …
·pubmed.ncbi.nlm.nih.gov·
[Virucidal efficacy of eight disinfectants against pneumovirus, coronavirus and parvovirus] - PubMed
Investigation on virucidal activity of chlorine dioxide. experimental data on feline calicivirus, HAV and Coxsackie B5 - PubMed
Investigation on virucidal activity of chlorine dioxide. experimental data on feline calicivirus, HAV and Coxsackie B5 - PubMed
"for complete inactivation of HAV and Feline calicivirus, concentrations > or = 0.6 mg/l are required. This observation is true for Coxsackie B5 too, but this virus has shown a good sensitivity at all concentration tested according to regression analysis results. For Feline calicivirus and HAV, at low concentrations of disinfectant, prolonged contact times were needed to obtain a 99.99% reduction of viral titres (about 16 and 20 minutes respectively). "
·pubmed.ncbi.nlm.nih.gov·
Investigation on virucidal activity of chlorine dioxide. experimental data on feline calicivirus, HAV and Coxsackie B5 - PubMed
Xenobiotic Effects of Chlorine Dioxide to Escherichia coli O157:H7 on Non-host Tomato Environment Revealed by Transcriptional Network Modeling: Implications to Adaptation and Selection - PubMed
Xenobiotic Effects of Chlorine Dioxide to Escherichia coli O157:H7 on Non-host Tomato Environment Revealed by Transcriptional Network Modeling: Implications to Adaptation and Selection - PubMed
The first hour of exposure to 1 μg and 5 μg ClO2 caused only partial killing with significant growth reduction starting at the second hour, and without further significant reduction at the third hour. However, 10 μg ClO2 exposure led to massive bacterial cell death at 1 h with further increase in cell death at 2 and 3 h. The first hour exposure to 1 μg ClO2 caused activation of primary defense and survival mechanisms. However, the defense response was attenuated during the second and third hours. Upon treatment with 5 μg ClO2, the transcriptional networks showed massive downregulation of pathogenesis and stress response genes at the first hour of exposure, with decreasing number of differentially expressed genes at the second and third hours. In contrast, more genes were further downregulated with exposure to 10 μg ClO2 at the first hour, with the number of both upregulated and downregulated genes significantly decreasing at the second hour. A total of 810 genes were uniquely upregulated at the third hour at 10 μg ClO2, suggesting that the potency of xenobiotic effects had led to potential adaptation.
·pubmed.ncbi.nlm.nih.gov·
Xenobiotic Effects of Chlorine Dioxide to Escherichia coli O157:H7 on Non-host Tomato Environment Revealed by Transcriptional Network Modeling: Implications to Adaptation and Selection - PubMed