Evaluation of lung tolerance of ethanol, propylene glycol, and sorbitan monooleate as solvents in medical aerosols.
ABSTRACT Aerosol therapy is an expanding technique allowing administration of drugs acting locally in the bronchial tree and lungs or acting systemically after absorption through the respiratory tract. However, the choice of solvents and adjuvants is a critical step in the formulation process of new drugs. Pulmonary tolerance of ethanol, propylene glycol and sorbitan ester was evaluated in a rat model of intratracheal administration using a Microsprayer in a 4-day toxicity study.
Four groups of Sprague-Dawley rats (11 rats per group, n = 44) have received, on 4 consecutive days 150 microL of solutions containing the solvents, by intratracheal route using a IA-1B-2 inches-Microsprayer (PennCentury, Philadelphia, PA). Once a day, the rats received deionized water (control) or ethanol 10% or propylene glycol 30% or sorbitan monooleate 10%. All rats were sacrificed 24 h after the fourth administration. Biochemical analysis on bronchoalveolar lavage (BAL) fluid was performed on seven rats per group. The respiratory tract of the remaining four rats/group was examined histologically.
Biochemistry and histopathology findings demonstrated that under the conditions tested, deionized water, 10% ethanol, and 30% propylene glycol were tolerated in a qualitatively similar way presenting limited cellular reaction. In contrast, 10% sorbitan monooleate produced an accumulation of foamy macrophages in the lungs and a higher degree of inflammation. In addition, animals in this group showed higher polymorphonuclear neutrophil recruitment and total proteins levels in BAL fluid.
The overall results recommended ranking the vehicles according to the degree of inflammation which was induced: deionized water <10% ethanol < or =30% propylene glycol <10% Tween 80.
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ABSTRACT: Electronic cigarette consumption ('vaping') is marketed as an alternative to conventional tobacco smoking. Technically, a mixture of chemicals containing carrier liquids, flavors, and optionally nicotine is vaporized and inhaled. The present study aims at the determination of the release of volatile organic compounds (VOC) and (ultra)fine particles (FP/UFP) from an e-cigarette under near-to-real-use conditions in an 8-m(3) emission test chamber. Furthermore, the inhaled mixture is analyzed in small chambers. An increase in FP/UFP and VOC could be determined after the use of the e-cigarette. Prominent components in the gas-phase are 1,2-propanediol, 1,2,3-propanetriol, diacetin, flavorings, and traces of nicotine. As a consequence, 'passive vaping' must be expected from the consumption of e-cigarettes. Furthermore, the inhaled aerosol undergoes changes in the human lung that is assumed to be attributed to deposition and evaporation. PRACTICAL IMPLICATIONS: The consumption of e-cigarettes marks a new source for chemical and aerosol exposure in the indoor environment. To evaluate the impact of e-cigarettes on indoor air quality and to estimate the possible effect of passive vaping, information about the chemical characteristics of the released vapor is needed.Indoor Air 06/2012; 23(1). DOI:10.1111/j.1600-0668.2012.00792.x · 4.20 Impact Factor
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ABSTRACT: Marketed since 2004 as an alternative to nicotine delivery and advertised as a valid means to smoking cessation, the electronic (e)-cigarette has been the subject of much controversy but very little experimental study. This review provides a brief summary of the current knowledge of this product. Propylene glycol and glycerol, the main ingredients of the fluid that is vaporized, have proved to be harmless in the fog machines of the entertainment industry. However, in the case of the e-cigarette fluid, the composition is not properly labeled: additives like nicotine and flavors vary between and within brands and contamination with various chemicals has been detected. The short-term toxicity seems low, but the long-term toxicity is unknown. The usefulness of the e-cigarette in smoking cessation has still to be clinically established. © 2013 S. Karger AG, Basel.Respiration 09/2013; 86(5). DOI:10.1159/000353253 · 2.92 Impact Factor
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ABSTRACT: With the rapid development of transportation industry and China's economy, the construction and development of low-carbon transportation system is the only way to realize the low-carbon and sustainable development of the transportation industry, and also is an important support to the energy -saving and emission reduction target and the healthy economic development. Based on the existing problems in the transportation system, the article analy zes the necessity of developing low-carbon transportation system, and puts up the three-party interaction model (government-transportation-public) and basic governance model.Energy Procedia 12/2011; 5:1502-1507. DOI:10.1016/j.egypro.2011.03.257