Nature the Enzyme-Substrate Com- Pounds of Catalase and Peroxides
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EH&S COVID-19 Chemical Disinfectant Safety Information
COVID-19 CHEMICAL DISINFECTANT SAFETY INFORMATION Updated June 24, 2020 The COVID-19 pandemic has caused an increase in the number of disinfection products used throughout UW departments. This document provides general information about EPA-registered disinfectants, such as potential health hazards and personal protective equipment recommendations, for the commonly used disinfectants at the UW. Chemical Disinfectant Base / Category Products Potential Hazards Controls ● Ethyl alcohol Highly flammable and could form explosive Disposable nitrile gloves Alcohols ● ● vapor/air mixtures. ● Use in well-ventilated areas away from o Clorox 4 in One Disinfecting Spray Ready-to-Use ● May react violently with strong oxidants. ignition sources ● Alcohols may de-fat the skin and cause ● Wear long sleeve shirt and pants ● Isopropyl alcohol dermatitis. ● Closed toe shoes o Isopropyl Alcohol Antiseptic ● Inhalation of concentrated alcohol vapor 75% Topical Solution, MM may cause irritation of the respiratory tract (Ready to Use) and effects on the central nervous system. o Opti-Cide Surface Wipes o Powell PII Disinfectant Wipes o Super Sani Cloth Germicidal Wipe 201 Hall Health Center, Box 354400, Seattle, WA 98195-4400 206.543.7262 ᅵ fax 206.543.3351ᅵ www.ehs.washington.edu ● Formaldehyde Formaldehyde in gas form is extremely Disposable nitrile gloves for Aldehydes ● ● flammable. It forms explosive mixtures with concentrations 10% or less ● Paraformaldehyde air. ● Medium or heavyweight nitrile, neoprene, ● Glutaraldehyde ● It should only be used in well-ventilated natural rubber, or PVC gloves for ● Ortho-phthalaldehyde (OPA) areas. concentrated solutions ● The chemicals are irritating, toxic to humans ● Protective clothing to minimize skin upon contact or inhalation of high contact concentrations. -
2011 Toxics Sampling Results for Benzene, Acetaldehyde, and Fromaldehyde
Iowa Toxics Sampling 2011 Results for Benzene, Acetaldehyde, and Formaldehyde Air Quality Bureau Iowa Department of Natural Resources Table of Contents Summary: Scope ..................................................................................................................................................................... 1 Sampling Schedules................................................................................................................................................................. 1 Data Capture ........................................................................................................................................................................... 1 Data Handling .......................................................................................................................................................................... 1 Precision Data ......................................................................................................................................................................... 1 Results of the Analysis ............................................................................................................................................................ 1 References .............................................................................................................................................................................. 2 Air Toxics Monitoring Network 2011 ..................................................................................................................................... -
EPA Method 8315A (SW-846): Determination of Carbonyl Compounds by High Performance Liquid Chromatography (HPLC)
METHOD 8315A DETERMINATION OF CARBONYL COMPOUNDS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) 1.0 SCOPE AND APPLICATION 1.1 This method provides procedures for the determination of free carbonyl compounds in various matrices by derivatization with 2,4-dinitrophenylhydrazine (DNPH). The method utilizes high performance liquid chromatography (HPLC) with ultraviolet/visible (UV/vis) detection to identify and quantitate the target analytes. This method includes two procedures encompassing all aspects of the analysis (extraction to determination of concentration). Procedure 1 is appropriate for the analysis of aqueous, soil and waste samples and stack samples collected by Method 0011. Procedure 2 is appropriate for the analysis of indoor air samples collected by Method 0100. The list of target analytes differs by procedure. The appropriate procedure for each target analyte is listed in the table below. Compound CAS No. a Proc. 1b Proc. 2 b Acetaldehyde 75-07-0 X X Acetone 67-64-1 X Acrolein 107-02-8 X Benzaldehyde 100-52-7 X Butanal (Butyraldehyde) 123-72-8 X X Crotonaldehyde 123-73-9 X X Cyclohexanone 108-94-1 X Decanal 112-31-2 X 2,5-Dimethylbenzaldehyde 5779-94-2 X Formaldehyde 50-00-0 X X Heptanal 111-71-7 X Hexanal (Hexaldehyde) 66-25-1 X X Isovaleraldehyde 590-86-3 X Nonanal 124-19-6 X Octanal 124-13-0 X Pentanal (Valeraldehyde) 110-62-3 X X Propanal (Propionaldehyde) 123-38-6 X X m-Tolualdehyde 620-23-5 X X o-Tolualdehyde 529-20-4 X p-Tolualdehyde 104-87-0 X a Chemical Abstract Service Registry Number. -
1.0 Introduction. This Method Describes the Sampling and Analysis Procedures of the Acetyl Acetone Colorimetric Method For
Method 323 8/7/2017 While we have taken steps to ensure the accuracy of this Internet version of the document, it is not the official version. To see a complete version including any recent edits, visit: https://www.ecfr.gov/cgi-bin/ECFR?page=browse and search under Title 40, Protection of Environment. METHOD 323—MEASUREMENT OF FORMALDEHYDE EMISSIONS FROM NATURAL GAS-FIRED STATIONARY SOURCES—ACETYL ACETONE DERIVITIZATION METHOD 1.0 Introduction. This method describes the sampling and analysis procedures of the acetyl acetone colorimetric method for measuring formaldehyde emissions in the exhaust of natural gas-fired, stationary combustion sources. This method, which was prepared by the Gas Research Institute (GRI), is based on the Chilled Impinger Train Method for Methanol, Acetone, Acetaldehyde, Methyl Ethyl Ketone, and Formaldehyde (Technical Bulletin No. 684) developed and published by the National Council of the Paper Industry for Air and Stream Improvement, Inc. (NCASI). However, this method has been prepared specifically for formaldehyde and does not include specifications (e.g., equipment and supplies) and procedures (e.g., sampling and analytical) for methanol, acetone, acetaldehyde, and methyl ethyl ketone. To obtain reliable results, persons using this method should have a thorough knowledge of at least Methods 1 and 2 of 40 CFR part 60, appendix A-1; Method 3 of 40 CFR part 60, appendix A-2; and Method 4 of 40 CFR part 60, appendix A-3. 1.1 Scope and Application 1.1.1 Analytes. The only analyte measured by this method is formaldehyde (CAS Number 50- 00-0). 1.1.2 Applicability. -
Ion-Molecule Reactions in Acetaldehyde and Methanol
MASS SPECTROSCOPY Original Papers Vol.20,No.4,December1972 Ion-Molecule Reactions in Acetaldehyde and Methanol SATOSHI OKADA*,AKIRA MATSUMOTO**,TAKAAKI DOHMARU*, SETSUO TANIGUCHI*AND TERUO HAYAKAWA** (Received10November1972) The thermal energy ion-molecule reactions in acetaldehyde and methanol have been studied by mass spectrometry using a pulsed ion source.The rate constants of transfer of light hydrogen and deuterium from methyl and formyl groups of acetaldehyde have been separately treated ,and those of transfer of light hyd rogen from methyl and formyl groups have been estimated to be0 .98•~10-9and1.97•~10-9cm3.molecule-1•E sec-1,respectively.In the methanol system ,the indirect isotope effect and the ion repeller voltage dependence on the rate constants for hydrogen transfer reactions are given and compared with the results reported by other workers. 1.Introduction these points,we have studied the thermal The studies of the ion-molecule re energy ion-molecule reactions of acetal actions involving polar molecules like dehyde and methanol including those acetaldehyde1),2)and methanol3),4)are of labeled with deuterium. interest in the field of ion-molecule reac tions itself,and have also given us many 2.Experimental important informations on the mechanisms The experiments were performed on a of the radiation chemical reactions in these Hitachi-RMU5 mass spectrometer pro systems. vided with the pulsed ion source which In the formation of protonated acetal had been described by Harrison and co dehyde from the reaction between the workers.7)The operating condition in this acetaldehyde ion and its neutral molecule, study was•|10V bias and10V pulse of however,the respective probabilities of 0.2ƒÊsec width to the electron beam slit, hydrogen transfer from methyl and formyl and10V pulse of1ƒÊsec width to the ion groups have not yet been evaluated. -
Acetaldehyde Production by Ethanol Dehydrogenation
Acetaldehyde Production by Ethanol Dehydrogenation Background Acetaldehyde is a colorless liquid with a pungent, fruity odor. It is primarily used as a chemical intermediate, principally for the production of acetic acid, pyridine and pyridine bases, peracetic acid, pentaeythritol, butylene glycol, and chloral. Acetaldehyde is a volatile and flammable liquid that is miscible in water, alcohol, ether, benzene, gasoline, and other common organic solvents. The goal of this project is to design a grass-roots facility that is capable of producing 95,000 tons of acetaldehyde per year by ethanol dehydrogenation. Process Description A preliminary base case BFD for the overall process is shown in Figure 1. Unit 100 A PFD of Unit 100 is shown in Figure 2. Ethanol, an 85-wt.% solution in water, Stream 1, is combined with 85-wt.% ethanol recycle stream, Stream 23, from Unit 200. The resultant stream, Stream 2, is then pumped to 100 psia and heated to 626°F in E-101 and E-102 before being fed to R-101, an isothermal, catalytic, packed-bed reactor, where the ethanol is dehydrogenated to form acetaldehyde. The reactor effluent is then cooled in E-103 and E-104. The resultant two-phase stream, Stream 8, is then separated in V- 101. The vapor, Stream 9, is sent to T-101 where it is contacted with water, which absorbs the acetaldehyde and ethanol from the vapor stream. The resulting vapor effluent, Stream 11, is then sent for further processing and recovery of valuable 2 hydrogen. Alternatively, this stream could be used as fuel. Stream 12, the liquid, is combined with Stream 14, the liquid effluent from V-101, and sent to Unit 200. -
Dehydrogenation of Ethanol to Acetaldehyde Over Different Metals Supported on Carbon Catalysts
catalysts Article Dehydrogenation of Ethanol to Acetaldehyde over Different Metals Supported on Carbon Catalysts Jeerati Ob-eye , Piyasan Praserthdam and Bunjerd Jongsomjit * Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand; [email protected] (J.O.-e.); [email protected] (P.P.) * Correspondence: [email protected]; Tel.: +66-2-218-6874 Received: 29 November 2018; Accepted: 27 December 2018; Published: 9 January 2019 Abstract: Recently, the interest in ethanol production from renewable natural sources in Thailand has been receiving much attention as an alternative form of energy. The low-cost accessibility of ethanol has been seen as an interesting topic, leading to the extensive study of the formation of distinct chemicals, such as ethylene, diethyl ether, acetaldehyde, and ethyl acetate, starting from ethanol as a raw material. In this paper, ethanol dehydrogenation to acetaldehyde in a one-step reaction was investigated by using commercial activated carbon with four different metal-doped catalysts. The reaction was conducted in a packed-bed micro-tubular reactor under a temperature range of 250–400 ◦C. The best results were found by using the copper doped on an activated carbon catalyst. Under this specified condition, ethanol conversion of 65.3% with acetaldehyde selectivity of 96.3% at 350 ◦C was achieved. This was probably due to the optimal acidity of copper doped on the activated carbon catalyst, as proven by the temperature-programmed desorption of ammonia (NH3-TPD). In addition, the other three catalyst samples (activated carbon, ceria, and cobalt doped on activated carbon) also favored high selectivity to acetaldehyde (>90%). -
Aldehydes Can React with Alcohols to Form Hemiacetals
340 14 . Nucleophilic substitution at C=O with loss of carbonyl oxygen You have, in fact, already met some reactions in which the carbonyl oxygen atom can be lost, but you probably didn’t notice at the time. The equilibrium between an aldehyde or ketone and its hydrate (p. 000) is one such reaction. O HO OH H2O + R1 R2 R1 R2 When the hydrate reverts to starting materials, either of its two oxygen atoms must leave: one OPh came from the water and one from the carbonyl group, so 50% of the time the oxygen atom that belonged to the carbonyl group will be lost. Usually, this is of no consequence, but it can be useful. O For example, in 1968 some chemists studying the reactions that take place inside mass spectrometers needed to label the carbonyl oxygen atom of this ketone with the isotope 18 O. 16 18 By stirring the ‘normal’ O compound with a large excess of isotopically labelled water, H 2 O, for a few hours in the presence of a drop of acid they were able to make the required labelled com- í In Chapter 13 we saw this way of pound. Without the acid catalyst, the exchange is very slow. Acid catalysis speeds the reaction up by making a reaction go faster by raising making the carbonyl group more electrophilic so that equilibrium is reached more quickly. The the energy of the starting material. We 18 also saw that the position of an equilibrium is controlled by mass action— O is in large excess. -
Expert Consensus Guidelines for Stocking of Antidotes in Hospitals That Provide Emergency Care
TOXICOLOGY/CONCEPTS Expert Consensus Guidelines for Stocking of Antidotes in Hospitals That Provide Emergency Care Richard C. Dart, MD, PhD From the Rocky Mountain Poison & Drug Center - Denver Health, Denver, CO (Dart, Heard, Schaeffer, Stephen W. Borron, MD, MS Bogdan, Alhelail, Buchanan, Hoppe, Lavonas, Mlynarchek, Phua, Rhyee, Varney, Zosel); Department of E. Martin Caravati, MD, MPH Surgery, University of Texas Health Sciences Center, San Antonio, TX (Borron); Division of Emergency Daniel J. Cobaugh, PharmD Medicine, Utah Poison Control Center, University of Utah Health Sciences Center, Salt Lake City, UT Steven C. Curry, MD (Caravati); ASHP Research and Education Foundation, Bethesda, MD (Cobaugh); Department of Jay L. Falk, MD Medical Toxicology and Banner Poison Control Center, Banner Good Samaritan Medical Center, Lewis Goldfrank, MD Phoenix, AZ (Curry); Department of Emergency Medicine, Orlando Regional Medical Center, University of Susan E. Gorman, PharmD, MS Florida, Orlando, FL (Falk); New York City Poison Center; New York University School of Medicine, New Stephen Groft, PharmD York, NY (Goldfrank); Division of Strategic National Stockpile, Centers for Disease Control and Kennon Heard, MD Prevention, Atlanta, GA (Gorman); Office of Rare Diseases Research, Bethesda, MD (Groft); Division of Ken Miller, MD, PhD Emergency Medicine, School of Medicine (Dart, Heard, Lavonas, Schaeffer) and Department of Kent R. Olson, MD Pharmaceutical Sciences, School of Pharmacy (Bogdan), University of Colorado Denver, Aurora, CO; Gerald O’Malley, DO Orange County Fire Authority and Orange County Health Care Agency Emergency Medical Services, Donna Seger, MD Irvine, CA, and National Association of EMS Physicians, Lenexa, KS, (Miller); University of California, Steven A. Seifert, MD San Francisco, and San Francisco Division, California Poison Control System, San Francisco, CA Marco L. -
How Is Alcohol Metabolized by the Body?
Overview: How Is Alcohol Metabolized by the Body? Samir Zakhari, Ph.D. Alcohol is eliminated from the body by various metabolic mechanisms. The primary enzymes involved are aldehyde dehydrogenase (ALDH), alcohol dehydrogenase (ADH), cytochrome P450 (CYP2E1), and catalase. Variations in the genes for these enzymes have been found to influence alcohol consumption, alcohol-related tissue damage, and alcohol dependence. The consequences of alcohol metabolism include oxygen deficits (i.e., hypoxia) in the liver; interaction between alcohol metabolism byproducts and other cell components, resulting in the formation of harmful compounds (i.e., adducts); formation of highly reactive oxygen-containing molecules (i.e., reactive oxygen species [ROS]) that can damage other cell components; changes in the ratio of NADH to NAD+ (i.e., the cell’s redox state); tissue damage; fetal damage; impairment of other metabolic processes; cancer; and medication interactions. Several issues related to alcohol metabolism require further research. KEY WORDS: Ethanol-to acetaldehyde metabolism; alcohol dehydrogenase (ADH); aldehyde dehydrogenase (ALDH); acetaldehyde; acetate; cytochrome P450 2E1 (CYP2E1); catalase; reactive oxygen species (ROS); blood alcohol concentration (BAC); liver; stomach; brain; fetal alcohol effects; genetics and heredity; ethnic group; hypoxia The alcohol elimination rate varies state of liver cells. Chronic alcohol con- he effects of alcohol (i.e., ethanol) widely (i.e., three-fold) among individ- sumption and alcohol metabolism are on various tissues depend on its uals and is influenced by factors such as strongly linked to several pathological concentration in the blood T chronic alcohol consumption, diet, age, consequences and tissue damage. (blood alcohol concentration [BAC]) smoking, and time of day (Bennion and Understanding the balance of alcohol’s over time. -
Reactions of Alcohols & Ethers 1
REACTIONS OF ALCOHOLS & ETHERS 1. Combustion (Extreme Oxidation) alcohol + oxygen carbon dioxide + water 2 CH3CH2OH + 6 O2 4 CO2 + 6 H2O 2. Elimination (Dehydration) ° alcohol H 2 S O 4/ 1 0 0 C alkene + water H2SO4/100 ° C CH3CH2CH2OH CH3CH=CH2 + H2O 3. Condensation ° excess alcohol H 2 S O 4 / 1 4 0 C ether + water H2SO4/140 ° C 2 CH3CH2OH CH3CH2OCH2CH3 + H2O 4. Substitution Lucas Reagent alcohol + hydrogen halide Z n C l2 alkyl halide + water ZnCl2 CH3CH2OH + HCl CH3CH2Cl + H2O • This reaction with the Lucas Reagent (ZnCl2) is a qualitative test for the different types of alcohols because the rate of the reaction differs greatly for a primary, secondary and tertiary alcohol. • The difference in rates is due to the solubility of the resulting alkyl halides • Tertiary Alcohol→ turns cloudy immediately (the alkyl halide is not soluble in water and precipitates out) • Secondary Alcohol → turns cloudy after 5 minutes • Primary Alcohol → takes much longer than 5 minutes to turn cloudy 5. Oxidation • Uses an oxidizing agent such as potassium permanganate (KMnO4) or potassium dichromate (K2Cr2O7). • This reaction can also be used as a qualitative test for the different types of alcohols because there is a distinct colour change. dichromate → chromium 3+ (orange) → (green) permanganate → manganese (IV) oxide (purple) → (brown) Tertiary Alcohol not oxidized under normal conditions CH3 KMnO4 H3C C OH NO REACTION K2Cr2O7 CH3 tertbutyl alcohol Secondary Alcohol ketone + hydrogen ions H O KMnO4 H3C C CH3 + K2Cr2O7 C + 2 H H3C CH3 OH propanone 2-propanol Primary Alcohol aldehyde + water carboxylic acid + hydrogen ions O KMnO4 O H H KMnO H H 4 + CH3CH2CH2OH C C C H C C C H + 2 H K2Cr2O7 + H2O K Cr O H H H 2 2 7 HO H H 1-propanol propanal propanoic acid 6. -
Chemical Disinfectants | Disinfection & Sterilization Guidelines | Guidelines Library | Infection Control | CDC 3/19/20, 14:52
Chemical Disinfectants | Disinfection & Sterilization Guidelines | Guidelines Library | Infection Control | CDC 3/19/20, 14:52 Infection Control Chemical Disinfectants Guideline for Disinfection and Sterilization in Healthcare Facilities (2008) Alcohol Overview. In the healthcare setting, “alcohol” refers to two water-soluble chemical compounds—ethyl alcohol and isopropyl alcohol —that have generally underrated germicidal characteristics 482. FDA has not cleared any liquid chemical sterilant or high- level disinfectant with alcohol as the main active ingredient. These alcohols are rapidly bactericidal rather than bacteriostatic against vegetative forms of bacteria; they also are tuberculocidal, fungicidal, and virucidal but do not destroy bacterial spores. Their cidal activity drops sharply when diluted below 50% concentration, and the optimum bactericidal concentration is 60%–90% solutions in water (volume/volume) 483, 484. Mode of Action. The most feasible explanation for the antimicrobial action of alcohol is denaturation of proteins. This mechanism is supported by the observation that absolute ethyl alcohol, a dehydrating agent, is less bactericidal than mixtures of alcohol and water because proteins are denatured more quickly in the presence of water 484, 485. Protein denaturation also is consistent with observations that alcohol destroys the dehydrogenases of Escherichia coli 486, and that ethyl alcohol increases the lag phase of Enterobacter aerogenes 487 and that the lag phase e!ect could be reversed by adding certain amino acids. The bacteriostatic action was believed caused by inhibition of the production of metabolites essential for rapid cell division. Microbicidal Activity. Methyl alcohol (methanol) has the weakest bactericidal action of the alcohols and thus seldom is used in healthcare 488. The bactericidal activity of various concentrations of ethyl alcohol (ethanol) was examined against a variety of microorganisms in exposure periods ranging from 10 seconds to 1 hour 483.