A study was conducted to establish whether volatile hydrocarbons, such as propane, n-butane and iso-butane, are metabolized in mice or not. In mice having inhaled these gases, isopropanol and acetone were yielded from propane, sec-butanol and methyl ethyl ketone from n-butane, and tert-butanol from iso-butane as the respective metabolites. In addition, liver microsomes were found to contain the enzymic system participating in these metabolisms. In vitro reactions with liver microsomes produced isopropanol from propane, sec-butanol from n-butane, and tert-butanol from iso-butane. It was assumed that hydrocarbons were first converted to (omega-1)-alcohols by microsomal enzyme system and then to corresponding ketones by alcohol dehydrogenase.
Hydroxylation of butane ... /occurs/ in rat liver microsomes to yield 2-butanol as the major metabolite. n-Butane is the lowest molecular weight alkane ... demonstrated to substrate-bind with cytochrome p450. ... If 2-butanol is the major metabolite formed in mammals, it would be expected to be eliminated in expired air. ... 2-Butanol may also be conjugated with glucuronic acid or be oxidized to methyl ethyl ketone which in turn is expired.
Purified liquefied petroleum gas (LPG), a mixture of butane, isobutane, and propane, is commonly abused by inhalation. Little is known about the mammalian metabolism of these substances. Metabolism of other hydrocarbons, including n-hexane and cyclohexane, has been studied in vitro using a range of liver preparations, with metabolites analyzed by static headspace techniques... Cyclohexanol and cyclohexanone were formed from cyclohexane and 1-, 2-, and 3-hexanol and 2-hexanone from n-hexane as predicted. Secondary alcohols are found for the other compounds studied, except for propene and isobutane, together with 2-propanone and 2-butanone from propane and n-butane, respectively. Samples from three individuals who died following LPG abuse contained a range of putative n-butane metabolites: n-butanol, 2-butanol, 2,3-butanediol, 3-hydroxy-2-butanone, and 2,3-butanedione. To /the authors/ knowledge, the last three compounds have not been proposed as metabolites of n-butane in man. These might be produced through similar metabolic pathways to those of n-hexane and n-heptane...
n-Butane is a colorless, flammable gas at room temperature. It occurs as a component in natural gas from which it is refined. n-Butane is used as fuel, refrigerant and aerosol propellant. The acute toxicity of n-butane has been studied after inhalation exposure in experimental animals. LC50 (4h) was 658 mg/l in rats and LC50 (2h) was 680 mg/l in mice. In dogs, lethal concentrations ranged from 474 to 592 mg/l. A concentration of 308 mg/l caused light anesthesia in mice within 25 minutes, and an exposure to 521 mg/l had similar effect within one minute. n-Butane ... sensitiz/ed/ the myocardium to epinephrine-induced cardiac arrhythmias in dogs after inhalation. No reports on acute toxicity of n-butane in experimental animals by other administration routes were located in the available literature. In a 21-day inhalation toxicity study of a mixture of n-butane, isobutane, n-penta and isopentane, containing 25% of each, the absence of toxicity was evident up to 11.8 mg/l which was the highest concentration tested. The study was performed in Sprague-Dawley rats which were exposed 6 hours per day over three weeks for a total of 15 exposures. No long-term studies using pure n-butane were located in the available literature. No mutagenic activity was observed in several tests in Salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 with or without the addition of an exogenous metabolism system. No studies on carcinogenicity, reproduction toxicity and teratogenicity, immunotoxicity or allergy were located in the available literature. Several reports on human exposure to n-butane were available. The increasing abuse of volatile substances, n-butane being among them, increases the risk of sudden death in connection to inhalation of the gas. The range of concentrations that may lead to "high" feelings or to death has been noted to be very narrow. The use of a oven cleaner containing n-butane as propellant has caused transient myoclonus in one patient. No other physical abnormalities were noted. An aerosol spray which contained n-butane as propellant, was reported to cause deep frostbite symptoms ir the skin when sprayed directly on it. Because of the anesthetic effect of n-butane, truck drivers and terminal operators from different loading facilities and service stations were examined for exposure gasoline vapours containing 90 to 92 percent n-butane, isobutane, n-pentane and isopentane. Exposures to the gasoline vapor were substantially lower than the established ACGIH threshold values (300 ppm or 0.89 mg/l for gasoline, and 800 ppm or 1.9 mg/l for n-butane). Occupational exposure of 53 male refinery workers for an average of 11 years to n-butane (concentration varied from 0.0004 mg/l to 0.0178 mg/l) did not cause any clinical symptoms in the workers. ... In conclusion, exposure to low concentrations of n-butane has not been reported to cause adverse effects in humans. It is anesthetic to both humans and experimental animals. Sudden death may occur when n-butane is inhaled at high concentrations. The safety margin between anesthetic and lethal concentrations appears to be very narrow. Chronic exposure to n-butane has been reported to cause some symptoms in the central nervous system. Critical effects might be lethality when inhaled in high doses, and effects on the central nervous system in chronically exposed individuals.
Butane is a simple asphyxiant and causes toxicity by displacing oxygen. It also affects the central nervous system by enhancing glycine receptors and inhibiting N-methyl-d-aspartate (NMDA) receptors. (L1284, A352)
Butane targets the central nervous system and cardiovascular system. Inhalation of butane can cause frostbite which can result in death from asphyxiation and ventricular fibrillation. (L1283, L1284)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
暴露途径
该物质可以通过吸入被身体吸收。
The substance can be absorbed into the body by inhalation.
来源:ILO-WHO International Chemical Safety Cards (ICSCs)
Inhalation studies ... in which rats and mice were exposed to lethal concn (27.8-29%) revealed that n-butane is absorbed and distributed to various tissues. After 4 hr of respiratory exposure, surviving rats were sacrificed ... concn of butane were ... highest in perinephric fat (2086 ppm), then brain (750 ppm), spleen (522 ppm), liver (492 ppm), and kidney (441 ppm). In mice exposed to 2 hr of butane vapors, the brain levels of n-butane were found to be 779 ppm. In both rats and mice the brain levels of n-butane correlated with the degree of CNS depression ... Dermal absorption of n-butane vapors has not been reported. However, dermal penetration of butane would not be expected to occur to any large extent since skin contact is transient because of volatility.
1.周国泰,化学危险品安全技术全书,化学工业出版社,1997 2.国家环保局有毒化学品管理办公室、北京化工研究院合编,化学品毒性法规环境数据手册,中国环境科学出版社.1992 3.Canadian Centre for Occupational Health and Safety,CHEMINFO Database.1998 4.Canadian Centre for Occupational Health and Safety, RTECS Database, 1989
Oxidation of Butane to Maleic Anhydride on Unmodified and Modified Vanadium-Phosphorus Catalysts
摘要:
研究了改性钒-磷催化剂的性质,并与未改性催化剂在丁烷氧化中的性能进行了比较。通过向催化剂晶格中引入钴,实现了最大的促进效果。在90%的转化率下,顺丁烯二酸酐的产量达到了59摩尔百分比。与未改性催化剂相比,用钴改性的催化剂将丁烷氧化和顺丁烯二酸酐形成的特定速率提高了三倍。催化剂的特定活性按以下顺序降低:Co > U ~ Ce > V-P-O > K ~ Mo。
Mechanistic Interrogation of Alkyne Hydroarylations Catalyzed by Highly Reduced, Single-Component Cobalt Complexes
作者:Benjamin A. Suslick、T. Don Tilley
DOI:10.1021/jacs.0c04072
日期:2020.6.24
complexes. Studies of the stoichiometric reaction of Co(I) or Co(II) precursors with CyMgCl implicated catalyst initiation via a β-H elimination/deprotonation pathway. The resulting single-component Co(-I) complex is proposed as the direct precatalyst. Michaelis-Menten enzyme kineticstudies provide mechanistic details regarding the catalytic dependence on substrate. The (N-aryl)aryl ethanimine substrate
Gas-phase reactions of iron(1-) and cobalt(1-) with simple thiols, sulfides, and disulfides by Fourier-transform mass spectrometry
作者:L. Sallans、K. R. Lane、B. S. Freiser
DOI:10.1021/ja00185a013
日期:1989.2
products, H-Fesup minus}}-SH and Fesup minus}}-SH. Some of the thermochemical data derived from this study include Ddegree}(Msup minus}}-S) > 103 kcal/mol and Ddegree}(Msup minus}}-SH) = 83 plus minus}9 kcal/mol. Finally, a brief survey of the reactivity of Vsup minus}}, Crsup minus}}, and Mosup minus}} with selected organosulfur compounds is also reported. 79 refs., 3 figs., 7 tabs
Investigation of the Mechanism of <i>n</i>-Butane Oxidation on Vanadium Phosphorus Oxide Catalysts: Evidence from Isotopic Labeling Studies
作者:Bin Chen、Eric J. Munson
DOI:10.1021/ja010285v
日期:2002.2.1
minimize total oxidation products such as CO and CO(2), the amounts of ethylene and carbon oxides produced from fully (13)C-labeled butane were almost equal. This strongly suggests that the total oxidation of n-butane on VPO catalysts involves the oxidation and abstraction of the two methyl groups of n-butane, and the two methylene groups of n-butane form ethylene. An organometallic mechanism is proposed