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Chu M, Wang R, Jing X, Li D, Fu G, Deng J, Xu Z, Zhao J, Liu Z, Fan Q, Pei L, Zeng Z, Liu C, Chen Z, Lu J, Liu XA. Conventional and multi-omics assessments of subacute inhalation toxicity due to propylene glycol and vegetable glycerin aerosol produced by electronic cigarettes. Ecotoxicol Environ Saf 2024; 271:116002. [PMID: 38277972 DOI: 10.1016/j.ecoenv.2024.116002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 01/09/2024] [Accepted: 01/18/2024] [Indexed: 01/28/2024]
Abstract
Propylene glycol (PG) and vegetable glycerin (VG) are the most common solvents used in electronic cigarette liquids. No long-term inhalation toxicity assessments have been performed combining conventional and multi-omics approaches on the potential respiratory effects of the solvents in vivo. In this study, the systemic toxicity of aerosol generated from a ceramic heating coil-based e-cigarette was evaluated. First, the aerosol properties were characterized, including carbonyl emissions, the particle size distribution, and aerosol temperatures. To determine toxicological effects, rats were exposed, through their nose only, to filtered air or a propylene glycol (PG)/ glycerin (VG) (50:50, %W/W) aerosol mixture at the target concentration of 3 mg/L for six hours daily over a continuous 28-day period. Compared with the air group, female rats in the PG/VG group exhibited significantly lower body weights during both the exposure period and recovery period, and this was linked to a reduced food intake. Male rats in the PG/VG group also experienced a significant decline in body weight during the exposure period. Importantly, rats exposed to the PG/VG aerosol showed only minimal biological effects compared to those with only air exposure, with no signs of toxicity. Moreover, the transcriptomic, proteomic, and metabolomic analyses of the rat lung tissues following aerosol exposure revealed a series of candidate pathways linking aerosol inhalation to altered lung functions, especially the inflammatory response and disease. Dysregulated pathways of arachidonic acids, the neuroactive ligand-receptor interaction, and the hematopoietic cell lineage were revealed through integrated multi-omics analysis. Therefore, our integrated multi-omics approach offers novel systemic insights and early evidence of environmental-related health hazards associated with an e-cigarette aerosol using two carrier solvents in a rat model.
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Affiliation(s)
- Ming Chu
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China; Laboratory of Life and Health Sciences, Shenzhen First union Technology Co., Ltd, Shenzhen 518103, China
| | - Ruoxi Wang
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Xiaoyuan Jing
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Ding Li
- Laboratory of Life and Health Sciences, Shenzhen First union Technology Co., Ltd, Shenzhen 518103, China; Laboratory of Life and Health Sciences, Shenzhen Health Union Biotechnology Co., Ltd, Shenzhen 518103, China
| | - Guofeng Fu
- Laboratory of Life and Health Sciences, Shenzhen First union Technology Co., Ltd, Shenzhen 518103, China
| | - Jingjing Deng
- Laboratory of Life and Health Sciences, Shenzhen Health Union Biotechnology Co., Ltd, Shenzhen 518103, China
| | - Zhibin Xu
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Jing Zhao
- Laboratory of Life and Health Sciences, Shenzhen Health Union Biotechnology Co., Ltd, Shenzhen 518103, China
| | - Zhang Liu
- Laboratory of Life and Health Sciences, Shenzhen Health Union Biotechnology Co., Ltd, Shenzhen 518103, China
| | - Qiming Fan
- Guangdong Zhongke EnHealth Science and Technology Co., Ltd. Foshan 528000, China
| | - Lanjie Pei
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, Wuhan 430079, China
| | - Zhi Zeng
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Chuan Liu
- Laboratory of Life and Health Sciences, Shenzhen First union Technology Co., Ltd, Shenzhen 518103, China
| | - Zuxin Chen
- Shenzhen Key Laboratory of Drug Addiction, Shenzhen Neher Neural Plasticity Laboratory, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences (CAS); Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jin Lu
- Laboratory of Life and Health Sciences, Shenzhen First union Technology Co., Ltd, Shenzhen 518103, China; Laboratory of Life and Health Sciences, Shenzhen Health Union Biotechnology Co., Ltd, Shenzhen 518103, China.
| | - Xin-An Liu
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Talih S, Karaoghlanian N, Salman R, Hilal E, Patev A, Bell A, Fallah S, El-Hage R, Saliba NA, Cobb C, Barnes A, Shihadeh A. Effects of Aftermarket Electronic Cigarette Pods on Device Power Output and Nicotine, Carbonyl, and ROS Emissions. Chem Res Toxicol 2023; 36:1930-1937. [PMID: 38032319 PMCID: PMC10731641 DOI: 10.1021/acs.chemrestox.3c00213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 12/01/2023]
Abstract
Aftermarket pods designed to operate with prevalent electronic nicotine delivery system (ENDS) products such as JUUL are marketed as low-cost alternatives that allow the use of banned flavored liquids. Subtle differences in the design or construction of aftermarket pods may intrinsically modify the performance of the ENDS device and the resulting nicotine and toxicant emissions relative to the original equipment manufacturer's product. In this study, we examined the electrical output of a JUUL battery and the aerosol emissions when four different brands of aftermarket pods filled with an analytical-grade mixture of propylene glycol, glycerol, and nicotine were attached to it and puffed by machine. The aerosol emissions examined included total particulate matter (TPM), nicotine, carbonyl compounds (CCs), and reactive oxygen species (ROS). We also compared the puff-resolved power and TPM outputs of JUUL and aftermarket pods. We found that all aftermarket pods drew significantly greater electrical power from the JUUL battery during puffing and had different electrical resistances and resistivity. In addition, unlike the case with the original pods, we found that with the aftermarket pods, the power provided by the battery did not vary greatly with flow rate or puff number, suggesting impairment of the temperature control circuitry of the JUUL device when used with the aftermarket pods. The greater power output with the aftermarket pods resulted in up to three times greater aerosol and nicotine output than the original product. ROS and CC emissions varied widely across brands. These results highlight that the use of aftermarket pods can greatly modify the performance and emissions of ENDS. Consumers and public health authorities should be made aware of the potential increase in the level of toxicant exposure when aftermarket pods are employed.
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Affiliation(s)
- Soha Talih
- Mechanical
Engineering Department, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Nareg Karaoghlanian
- Mechanical
Engineering Department, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Rola Salman
- Mechanical
Engineering Department, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Elissa Hilal
- Mechanical
Engineering Department, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
| | - Alison Patev
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Ashlynn Bell
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Sacha Fallah
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
- Chemistry
Department, Faculty of Arts and Sciences, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
| | - Rachel El-Hage
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
- Chemistry
Department, Faculty of Arts and Sciences, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
| | - Najat Aoun Saliba
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
- Chemistry
Department, Faculty of Arts and Sciences, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
| | - Caroline Cobb
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
| | - Andrew Barnes
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
- Department
of Health Behavior and Policy, Virginia
Commonwealth University, 830 E. Main St., Richmond, Virginia 23219, United States
| | - Alan Shihadeh
- Mechanical
Engineering Department, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Bliss Street, PO. Box 11-0236, Beirut 1107-2020, Lebanon
- Center
for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, 821 West Franklin Street, Richmond, Virginia 23284, United States
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Hua M, Luo W, Khachatoorian C, McWhirter KJ, Leung S, Martinez T, Talbot P. Exposure, Retention, Exhalation, Symptoms, and Environmental Accumulation of Chemicals During JUUL Vaping. Chem Res Toxicol 2023; 36:492-507. [PMID: 36867872 DOI: 10.1021/acs.chemrestox.2c00390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Little is known about the chemical exposures that electronic cigarette (EC) users receive and emit during JUUL vaping and if exposures produce symptoms dose dependently. This study examined chemical exposure (dose), retention, symptoms during vaping, and the environmental accumulation of exhaled propylene glycol (PG), glycerol (G), nicotine, and menthol in a cohort of human participants who vaped JUUL "Menthol" ECs. We refer to this environmental accumulation as "EC exhaled aerosol residue" (ECEAR). Chemicals were quantified using gas chromatography/mass spectrometry in JUUL pods before and after use, lab-generated aerosols, human exhaled aerosols, and in ECEAR. Unvaped JUUL "Menthol" pods contained ∼621.3 mg/mL of G, ∼264.9 mg/mL of PG, ∼59.3 mg/mL of nicotine, ∼13.3 mg/mL of menthol, and ∼0.1 mg/mL of the coolant WS-23. Eleven experienced male EC users (aged 21-26) provided exhaled aerosol and residue samples before and after vaping JUUL pods. Participants vaped ad libitum for 20 min, while their average puff count (22 ± 6.4) and puff duration (4.4 ± 2.0) were recorded. The transfer efficiency of nicotine, menthol, and WS-23 from the pod fluid into the aerosol varied with each chemical and was generally similar across flow rates (9-47 mL/s). At 21 mL/s, the average mass of each chemical retained by the participants who vaped 20 min was 53.2 ± 40.3 mg for G, 18.9 ± 14.3 mg for PG, 3.3 ± 2.7 mg for nicotine, and 0.5 ± 0.4 mg for menthol, with retention deduced to be ∼90-100% for each chemical. There was a significant positive relationship between the number of symptoms during vaping and total chemical mass retained. ECEAR accumulated on enclosed surfaces where it could contribute to passive exposure. These data will be valuable to researchers studying human exposure to EC aerosols and agencies that regulate EC products.
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Affiliation(s)
- My Hua
- Environmental Toxicology Graduate Program, University of California, Riverside, Riverside, California 92521, United States
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Wentai Luo
- Department of Civil and Environmental Engineering, Portland State University, Portland, Oregon 97201, United States
| | - Careen Khachatoorian
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Kevin J McWhirter
- Department of Civil and Environmental Engineering, Portland State University, Portland, Oregon 97201, United States
| | - Sara Leung
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Teresa Martinez
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Prue Talbot
- Environmental Toxicology Graduate Program, University of California, Riverside, Riverside, California 92521, United States
- Department of Molecular, Cell and Systems Biology, University of California, Riverside, Riverside, California 92521, United States
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Edmiston JS, Rostami AA, Liang Q, Miller S, Sarkar MA. Computational modeling method to estimate secondhand exposure potential from exhalations during e-vapor product use under various real-world scenarios. Intern Emerg Med 2022; 17:2005-2016. [PMID: 36050572 PMCID: PMC9522680 DOI: 10.1007/s11739-022-03061-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 07/20/2022] [Indexed: 11/05/2022]
Abstract
Potential secondhand exposure of exhaled constituents from e-vapor product (EVP) use is a public health concern. We present a computational modeling method to predict air levels of exhaled constituents from EVP use. We measured select constituent levels in exhaled breath from adult e-vapor product users, then used a validated computational model to predict constituent levels under three scenarios (car, office, and restaurant) to estimate likely secondhand exposure to non-users. The model was based on physical/thermodynamic interactions between air, vapor, and particulate phase of the aerosol. Input variables included space setting, ventilation rate, total aerosol amount exhaled, and aerosol composition. Exhaled breath samples were analyzed after the use of four different e-liquids in a cartridge-based EVP. Nicotine, propylene glycol, glycerin, menthol, formaldehyde, acetaldehyde, and acrolein levels were measured and reported based on a linear mixed model for analysis of covariance. The ranges of nicotine, propylene glycol, glycerin, and formaldehyde in exhaled breath were 89.44-195.70 µg, 1199.7-3354.5 µg, 5366.8-6484.7 µg, and 0.25-0.34 µg, respectively. Acetaldehyde and acrolein were below detectable limits; thus, no estimated exposure to non-EVP users is reported. The model predicted that nicotine and formaldehyde exposure to non-users was substantially lower during EVPs use compared to cigarettes. The model also predicted that exposure to propylene glycol, glycerin, nicotine and formaldehyde among non-users was below permissible exposure limits.
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Affiliation(s)
- Jeffery S Edmiston
- Center for Research and Technology, Altria Client Services LLC, 601 East Jackson Street, Richmond, VA, 23219, USA
| | - Ali A Rostami
- Center for Research and Technology, Altria Client Services LLC, 601 East Jackson Street, Richmond, VA, 23219, USA
| | - Qiwei Liang
- Center for Research and Technology, Altria Client Services LLC, 601 East Jackson Street, Richmond, VA, 23219, USA
| | - Sandra Miller
- Center for Research and Technology, Altria Client Services LLC, 601 East Jackson Street, Richmond, VA, 23219, USA
| | - Mohamadi A Sarkar
- Center for Research and Technology, Altria Client Services LLC, 601 East Jackson Street, Richmond, VA, 23219, USA.
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Guo X, Ehindero T, Lau C, Zhao R. Impact of glycol-based solvents on indoor air quality-Artificial fog and exposure pathways of formaldehyde and various carbonyls. Indoor Air 2022; 32:e13100. [PMID: 36168228 DOI: 10.1111/ina.13100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 07/20/2022] [Accepted: 08/02/2022] [Indexed: 06/16/2023]
Abstract
Artificial fog is commonly employed in the entertainment industry and indoor household celebrations. The fog is generated from glycol-based solvents, which can also be found in e-cigarettes and personal care products. Although potential health impacts of glycol inhalation are frequently cited by studies of e-cigarette smoking, the dynamics and the chemical composition of glycol-based aerosols have never been studied systematically. The objective of this work is to investigate the impact of glycol-based aerosol on indoor air quality. Specifically, we targeted artificial fogs generated with common glycols, including propylene glycol (PG) and triethylene glycol (TEG). With the aid of a novel aerosol collecting and monitoring instrument setup, we obtained time-resolved aerosol profiles and their chemical compositions in an experimental room. Artificial fog has given rise to a significant amount of ultra-fine particulate matter, demonstrating its negative impact on indoor air quality. Additionally, we found a high concentration (9.75 mM) of formaldehyde and other carbonyls in fog machine fluids stored for months. These compounds are introduced to the indoor air upon artificial fog application. We propose that carbonyls have accumulated from the oxidative decomposition of glycols, initiated by OH radicals and singlet oxygens (1 O2 ) and likely sustained by autooxidation. Oxidation of glycols by indoor oxidants has never been reported previously. Such chemical processes can represent an unrecognized source of toxic carbonyl compounds which is also applicable to other glycol-based solvents.
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Affiliation(s)
- Xinyang Guo
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Toluwatise Ehindero
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Chester Lau
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
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Kerber PJ, Duell AK, Peyton DH. Ratio of Propylene Glycol to Glycerol in E-Cigarette Reservoirs Is Unchanged by Vaping As Determined by 1H NMR Spectroscopy. Chem Res Toxicol 2021; 34:1846-1849. [PMID: 34347480 PMCID: PMC10857734 DOI: 10.1021/acs.chemrestox.1c00208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
E-cigarette liquids (e-liquids) contain propylene glycol (PG) and/or glycerol (GL) to deliver flavorants/nicotine. It has recently been suggested that the PG:GL ratio in e-cigarette reservoirs changes during vaping, leaving almost entirely GL after aerosolizing much of a 30:70 PG:GL mixture. To evaluate this directly, we analyzed e-liquids from e-cigarettes before and after aerosolization using 4 different coils, and aerosol samples generated using high and low e-liquid levels. The PG:GL ratios of initial and final e-liquids and aerosol samples were comparable. This is important because a large change in e-liquid composition could substantially alter the aerosol profile during a vaping session.
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Affiliation(s)
- Paul J Kerber
- Department of Chemistry, Portland State University, Portland, Oregon 97207-0751, United States
| | - Anna K Duell
- Department of Chemistry, Portland State University, Portland, Oregon 97207-0751, United States
| | - David H Peyton
- Department of Chemistry, Portland State University, Portland, Oregon 97207-0751, United States
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Czekala L, Chapman F, Simms L, Rudd K, Trelles Sticken E, Wieczorek R, Bode LM, Pani J, Moelijker N, Derr R, Brandsma I, Hendriks G, Stevenson M, Walele T. The in vitro ToxTracker and Aneugen Clastogen Evaluation extension assay as a tool in the assessment of relative genotoxic potential of e-liquids and their aerosols. Mutagenesis 2021; 36:129-142. [PMID: 33769537 PMCID: PMC8166346 DOI: 10.1093/mutage/geaa033] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/24/2020] [Indexed: 12/14/2022] Open
Abstract
In vitro (geno)toxicity assessment of electronic vapour products (EVPs), relative to conventional cigarette, currently uses assays, including the micronucleus and Ames tests. Whilst informative on induction of a finite endpoint and relative risk posed by test articles, such assays could benefit from mechanistic supplementation. The ToxTracker and Aneugen Clastogen Evaluation analysis can indicate the activation of reporters associated with (geno)toxicity, including DNA damage, oxidative stress, the p53-related stress response and protein damage. Here, we tested for the different effects of a selection of neat e-liquids, EVP aerosols and Kentucky reference 1R6F cigarette smoke samples in the ToxTracker assay. The assay was initially validated to assess whether a mixture of e-liquid base components, propylene glycol (PG) and vegetable glycerine (VG) had interfering effects within the system. This was achieved by spiking three positive controls into the system with neat PG/VG or phosphate-buffered saline bubbled (bPBS) PG/VG aerosol (nicotine and flavour free). PG/VG did not greatly affect responses induced by the compounds. Next, when compared to cigarette smoke samples, neat e-liquids and bPBS aerosols (tobacco flavour; 1.6% freebase nicotine, 1.6% nicotine salt or 0% nicotine) exhibited reduced and less complex responses. Tested up to a 10% concentration, EVP aerosol bPBS did not induce any ToxTracker reporters. Neat e-liquids, tested up to 1%, induced oxidative stress reporters, thought to be due to their effects on osmolarity in vitro. E-liquid nicotine content did not affect responses induced. Additionally, spiking nicotine alone only induced an oxidative stress response at a supraphysiological level. In conclusion, the ToxTracker assay is a quick, informative screen for genotoxic potential and mechanisms of a variety of (compositionally complex) samples, derived from cigarettes and EVPs. This assay has the potential for future application in the assessment battery for next-generation (smoking alternative) products, including EVPs.
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Affiliation(s)
- Lukasz Czekala
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
| | - Fiona Chapman
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
| | - Liam Simms
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
| | - Kathryn Rudd
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
| | - Edgar Trelles Sticken
- Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Albert-Einstein-Ring-7, D-22761 Hamburg, Germany
| | - Roman Wieczorek
- Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Albert-Einstein-Ring-7, D-22761 Hamburg, Germany
| | - Lisa Maria Bode
- Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Albert-Einstein-Ring-7, D-22761 Hamburg, Germany
| | - Jutta Pani
- Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Albert-Einstein-Ring-7, D-22761 Hamburg, Germany
| | - Nynke Moelijker
- Toxys B.V., Robert Boyleweg 4, 2333 CG Leiden, The Netherlands
| | - Remco Derr
- Toxys B.V., Robert Boyleweg 4, 2333 CG Leiden, The Netherlands
| | - Inger Brandsma
- Toxys B.V., Robert Boyleweg 4, 2333 CG Leiden, The Netherlands
| | - Giel Hendriks
- Toxys B.V., Robert Boyleweg 4, 2333 CG Leiden, The Netherlands
| | - Matthew Stevenson
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
| | - Tanvir Walele
- Group Science and Regulatory Affairs, Imperial Brands PLC, Bristol, UK
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Soremekun R, Ogbuefi I, Aderemi-Williams R. Prevalence of ethanol and other potentially harmful excipients in pediatric oral medicines: survey of community pharmacies in a Nigerian City. BMC Res Notes 2019; 12:460. [PMID: 31349864 PMCID: PMC6660694 DOI: 10.1186/s13104-019-4486-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 07/15/2019] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE Excipients are needed in the formulation of oral liquid medicines intended for children; they have however been reported to trigger safety issues. This study evaluated the concentrations and prevalence of ethanol and other potentially harmful excipients in pediatric formulations marketed in South Eastern Nigeria in line with international labeling guidelines and allowable daily limits (ADL). The study sampled oral pediatric formulations offered for sale in registered pharmacies. Those with accessible information leaflets were assessed for the presence and quantity of previously flagged excipients with potential to harm the pediatric population. RESULT Of the 380 oral pediatric medicines, 140 provided access to list/quantity of ingredients. 47.9% (67) of the formulations contain at least one of the flagged excipients while the remaining only listed the active ingredients. Ethanol had the highest occurrence (62.7%) and was more in cough/cold medicines. A homeopathic cough and cold remedy had concentration of 90% v/v. Ethanol and sucrose in some formulations exhibited concentrations with a potential of crossing their approved daily intake (ADI) (1-90% v/v and 1.7 g-3.7 g/5 ml respectively). Ethanol use in studied pediatric formulations was quite high, with ethanol-containing formulations being prescribed for children 0-6 years and older. Only 26 (38.8%) completely satisfied the labelling requirements for ethanol containing formulations.
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Affiliation(s)
- Rebecca Soremekun
- Department of Clinical Pharmacy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
- Faculty of Public Health, West African Postgraduate College of Pharmacists, Lagos, Nigeria
| | - Irene Ogbuefi
- Faculty of Public Health, West African Postgraduate College of Pharmacists, Lagos, Nigeria
| | - Roseline Aderemi-Williams
- Department of Clinical Pharmacy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
- Faculty of Public Health, West African Postgraduate College of Pharmacists, Lagos, Nigeria
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Soulet S, Duquesne M, Toutain J, Pairaud C, Lalo H. Experimental Method of Emission Generation Calibration Based on Reference Liquids Characterization. Int J Environ Res Public Health 2019; 16:ijerph16132262. [PMID: 31248048 PMCID: PMC6651204 DOI: 10.3390/ijerph16132262] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 11/16/2022]
Abstract
This work focuses on an experimental study of the influence of e-liquid composition on the mass of vaporized e-liquid after standardized emission generation using a U-SAV (Universal System for Analysis of Vaping) vaping machine. All the experiments were based on the use of a Cubis 1Ω clearomiser and on the standard protocol for electronic cigarettes emission generation. Currently, there is no standardized method available to calibrate the emission generations of electronic cigarettes. Since the e-liquid compositions are not always known, we propose a simple, practical, effective, and fast method of emission generation calibration. Therefore, this paper examines a major issue in this new and constantly evolving field, allowing the validation of the emission generation results. To our knowledge, this method is a novelty in our discipline and could be easily developed in laboratories. Pure propylene-glycol, glycerol, ethanol, and water and their mixtures (20 e-liquids) were tested as reference materials, allowing an e-liquids benchmarking and the characterization of 800 commercial e-liquids (with known and unknown compositions) at a fixed power and for one inhalation profile (3 s puff duration and 55 mL of puff volume). The influence of ethanol and/or water addition in the e-liquid was characterized.
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Affiliation(s)
- Sébastien Soulet
- Laboratoire Français du E-Liquide, 218 avenue du Haut-Levêque, 33600 Pessac, France.
- Université de Bordeaux, CNRS, I2M Bordeaux, Site ENSAM, Esplanade des Arts et Métiers, F-33405 Talence CEDEX, France.
| | - Marie Duquesne
- Bordeaux INP, CNRS, I2M Bordeaux, ENSCBP, 16 avenue Pey Berland, 33607 Pessac CEDEX, France
| | - Jean Toutain
- Bordeaux INP, CNRS, I2M Bordeaux, ENSCBP, 16 avenue Pey Berland, 33607 Pessac CEDEX, France
| | - Charly Pairaud
- Laboratoire Français du E-Liquide, 218 avenue du Haut-Levêque, 33600 Pessac, France
| | - Hélène Lalo
- Laboratoire Français du E-Liquide, 218 avenue du Haut-Levêque, 33600 Pessac, France
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10
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Abstract
The study of e-cigarette aerosol properties can inform public health while longer-term epidemiological investigations are ongoing. The determination of aerosol levels of known toxins, as well as of molecules with unknown inhalation toxicity profiles, affords specific information for estimating the risks of e-cigarettes and for uncovering areas that should be prioritized for further investigation.
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Affiliation(s)
- Robert M Strongin
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA;
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11
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da Silva Oliveira W, Ubeda S, Nerín C, Padula M, Teixeira Godoy H. Identification of non-volatile migrants from baby bottles by UPLC-Q-TOF-MS. Food Res Int 2019; 123:529-537. [PMID: 31285002 DOI: 10.1016/j.foodres.2019.05.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 12/17/2022]
Abstract
Baby bottles made of polypropylene, Tritan® and silicone were evaluated regarding the migration of non-volatile compounds using UPLC-QTOF-MS. Twenty-seven compounds were identified. In all polypropylene samples the migration of 2.2'-(tridecylimino)bis-ethanol and derivatives thereof were detected in concentrations below the specific migration limit (1.2 mg.kg-1). Furthermore, clarifying agents and glycerol derivatives were detected. Tritan baby bottle showed the migration of one slip additive. On the other hand, twenty compounds were detected in silicone baby bottles. Most of them were unknown compounds derived from acrylates. Once the migrants were identified, the risk assessment was carried out using the Threshold of Toxicological Concern (TTC) approach. The risk assessment of migrants coming from silicone samples showed levels above the threshold recommended as safe for babies.
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Affiliation(s)
| | - Sara Ubeda
- Department of Analytical Chemistry, GUIA Group, Aragon Institute of Engineering Research I3A, University of Zaragoza, Zaragoza, Spain
| | - Cristina Nerín
- Department of Analytical Chemistry, GUIA Group, Aragon Institute of Engineering Research I3A, University of Zaragoza, Zaragoza, Spain.
| | - Marisa Padula
- Packaging Technology Center, Institute of Food Technology (ITAL), Campinas, SP, Brazil
| | - Helena Teixeira Godoy
- Department of Food Science, School of Food Engineering, University of Campinas (UNICAMP), Campinas, SP, Brazil
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12
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Bansal M, Sharma M, Bullen C, Svirskis D. A Stability Indicating HPLC Method to Determine Actual Content and Stability of Nicotine within Electronic Cigarette Liquids. Int J Environ Res Public Health 2018; 15:E1737. [PMID: 30104538 PMCID: PMC6121411 DOI: 10.3390/ijerph15081737] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/07/2018] [Accepted: 08/10/2018] [Indexed: 11/16/2022]
Abstract
(1) Background: Despite the growing use of e-cigarettes, in most countries, there is no regulation covering manufacturing standards of the solution ('e-liquid'), leading to concerns over the accuracy of labelling and stability of the products under a range of conditions. Following the United States (US) Food and Drug Administration (FDA) requirements for manufacture of e-liquids, we aimed to develop a simple high-performance liquid chromatography (HPLC) method to determine nicotine content in nicotine-containing e-liquids, even in the presence of degradation products; (2) Methods: We developed an HPLC method to quantify nicotine in the presence of the two major constituents of all e-liquids, glycerine and propylene glycol, and in the presence of degradation products; (3) Results: Our HPLC method performed strongly and was validated it according to international guidelines. For the e-liquids tested, nicotine content levels were all higher than labelled (up to 117.9 ± 1.87% of the labelled content). While nicotine was shown to be unstable at 60 °C, it was stabilized at this temperature in the e-liquid formulations for up to 10 days; and (4) Conclusions: The HPLC method is suitable for adoption by laboratories to determine the actual content and stability of nicotine-containing products. The higher than labelled nicotine levels in e-liquids raises clinical and public health concerns.
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Affiliation(s)
- Mahima Bansal
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland 1023, New Zealand.
| | - Manisha Sharma
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland 1023, New Zealand.
| | - Chris Bullen
- National Institute for Health Innovation, The University of Auckland, Auckland 1010, New Zealand.
| | - Darren Svirskis
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland 1023, New Zealand.
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13
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Frasch HF, Barbero AM. In vitro human epidermal permeation of nicotine from electronic cigarette refill liquids and implications for dermal exposure assessment. J Expo Sci Environ Epidemiol 2017; 27:618-624. [PMID: 27924817 PMCID: PMC6322548 DOI: 10.1038/jes.2016.68] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/21/2016] [Accepted: 10/25/2016] [Indexed: 05/19/2023]
Abstract
Nicotine plus flavorings in a propylene glycol (PG) vehicle are the components of electronic cigarette liquids (e-liquids), which are vaporized and inhaled by the user. Dermal exposure to nicotine and e-liquids may occur among workers in mixing and filling of e-cigarettes in the manufacturing process. Inadvertent skin contact among consumers is also a concern. In vitro nicotine permeation studies using heat-separated human epidermis were performed with surrogate and two commercial e-liquids, neat and aqueous nicotine donor formulations. Steady-state fluxes (Jss), and lag times (tlag) were measured for each formulation. In addition, transient (4 h) exposure and finite dose (1-10 μl/cm2) experiments were undertaken using one commercial e-liquid. Average Jss (μg/cm2/h) from formulations were: nicotine in PG (24 mg/ml): 3.97; commercial e-liquid containing menthol (25 mg/ml nicotine): 10.2; commercial e-liquid containing limonene (25 mg/ml nicotine): 23.7; neat nicotine: 175. E-liquid lag times ranged from 5 to 10 h. Absorbed fraction of nicotine from finite doses was ≈0.3 at 48 h. The data were applied to transient exposure and finite dose dermal exposure assessment models and to a simple pharmacokinetic model. Three illustrative exposure scenarios demonstrate use of the data to predict systemic uptake and plasma concentrations from dermal exposure. The data demonstrate the potential for significant nicotine absorption through skin contact with e-cigarette refill solutions and the neat nicotine used to mix them.
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Affiliation(s)
- H Frederick Frasch
- Health Effects Laboratory, National Institute for Occupational Safety and Health, Morgantown, West Virginia, USA
| | - Ana M Barbero
- Health Effects Laboratory, National Institute for Occupational Safety and Health, Morgantown, West Virginia, USA
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14
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Abstract
There are over 2.6 million users of e-cigarettes in the United Kingdom alone as they have been promoted as a safer alternative to traditional cigarettes. The addition of flavours and aromas has also proven to be popular with younger generations. In this review, we survey the range of studies in the short timeframe since e-cigarettes reached the market to draw attention to the health associated risks and benefits of their introduction. We complement this review with a case study reporting on the composition of selected e-cigarette refills with particular emphasis on the toxicological activity of its components on lung cells.
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Affiliation(s)
- Jasjot Singh
- Department of Biology and Chemistry at the University of Applied Sciences Bremen
| | - Emilie Luquet
- Department of Biology at the IUT Universite d'Auvergne
| | - David P.T. Smith
- Specialist Research Infrastructure Technician at the School of Environment and Life Sciences at the University of Salford
| | - Herman J. Potgieter
- Division of Chemistry and Environmental Science, Manchester Metropolitan University
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15
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Crenshaw MD, Tefft ME, Buehler SS, Brinkman MC, Clark PI, Gordon SM. Determination of nicotine, glycerol, propylene glycol and water in electronic cigarette fluids using quantitative 1 H NMR. Magn Reson Chem 2016; 54:901-904. [PMID: 27495876 PMCID: PMC5069187 DOI: 10.1002/mrc.4498] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 07/15/2016] [Accepted: 08/01/2016] [Indexed: 06/01/2023]
Abstract
The variability of the electronic cigarette liquids (e-liquid) composition has the potential to influence not only the amount of nicotine delivered to the user, but also the type and amount of generated byproducts and subsequent health risks. For this reason, it is important to characterize all of the chemical components of e-liquids. We report the development and application of a single 1H NMR analysis method to identify and quantify the most abundant chemical components (nicotine, glycerol, 1,2-propylene glycol, and water) likely to be present as their influence on the composition of inhaled vapor is not know. For 1H NMR, the solvent has to dissolve the e-liquids at a concentration sufficient to readily determine the concentration of nicotine present, and the solvent and internal standard cannot possess exchangeable protons which would interfere with determining the concentrations of the analytes of interest. To fulfill these requirements, perdeuterated N,N-dimethylformamide (DMF-d7) was selected as the solvent, with 1,2,4,5-tetrachloro-3-nitrobenzene as the internal standard. Nicotine concentrations from 58 different e-liquids obtained using 1H NMR were found to agree with the results from GC-MS analysis. Generally, the amount of nicotine present was close to that claimed by the manufacturer. In some cases, the proportions of 1,2-propylene glycol, glycerol, and water varied significantly between flavors within a brand and within flavors depending on the nicotine content. In one case, 1,2-propylene glycol was identified where the manufacturer had stated none should be present.
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Affiliation(s)
- Michael D Crenshaw
- Battelle Public Health Center for Tobacco Research, 505 King Avenue, Columbus, OH, 43201, USA.
| | - Margaret E Tefft
- Battelle Public Health Center for Tobacco Research, 505 King Avenue, Columbus, OH, 43201, USA
| | - Stephanie S Buehler
- Battelle Public Health Center for Tobacco Research, 505 King Avenue, Columbus, OH, 43201, USA
| | - Marielle C Brinkman
- Battelle Public Health Center for Tobacco Research, 505 King Avenue, Columbus, OH, 43201, USA
| | - Pamela I Clark
- University of Maryland, School of Public Health, 2242 Valley Drive, College Park, MD, 20742, USA
| | - Sydney M Gordon
- Battelle Public Health Center for Tobacco Research, 505 King Avenue, Columbus, OH, 43201, USA
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16
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Maloney JC, Thompson MK, Oldham MJ, Stiff CL, Lilly PD, Patskan GJ, Shafer KH, Sarkar MA. Insights from two industrial hygiene pilot e-cigarette passive vaping studies. J Occup Environ Hyg 2016; 13:275-83. [PMID: 26576834 DOI: 10.1080/15459624.2015.1116693] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
While several reports have been published using research methods of estimating exposure risk to e-cigarette vapors in nonusers, only two have directly measured indoor air concentrations from vaping using validated industrial hygiene sampling methodology. Our first study was designed to measure indoor air concentrations of nicotine, menthol, propylene glycol, glycerol, and total particulates during the use of multiple e-cigarettes in a well-characterized room over a period of time. Our second study was a repeat of the first study, and it also evaluated levels of formaldehyde. Measurements were collected using active sampling, near real-time and direct measurement techniques. Air sampling incorporated industrial hygiene sampling methodology using analytical methods established by the National Institute of Occupational Safety and Health and the Occupational Safety and Health Administration. Active samples were collected over a 12-hr period, for 4 days. Background measurements were taken in the same room the day before and the day after vaping. Panelists (n = 185 Study 1; n = 145 Study 2) used menthol and non-menthol MarkTen prototype e-cigarettes. Vaping sessions (six, 1-hr) included 3 prototypes, with total number of puffs ranging from 36-216 per session. Results of the active samples were below the limit of quantitation of the analytical methods. Near real-time data were below the lowest concentration on the established calibration curves. Data from this study indicate that the majority of chemical constituents sampled were below quantifiable levels. Formaldehyde was detected at consistent levels during all sampling periods. These two studies found that indoor vaping of MarkTen prototype e-cigarette does not produce chemical constituents at quantifiable levels or background levels using standard industrial hygiene collection techniques and analytical methods.
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Affiliation(s)
- John C Maloney
- a Safety, Health and Environmental, Altria Client Services Inc. , Richmond , Virginia
| | - Michael K Thompson
- a Safety, Health and Environmental, Altria Client Services Inc. , Richmond , Virginia
| | - Michael J Oldham
- b Regulatory Affairs, Altria Client Services Inc. , Richmond , Virginia
| | - Charles L Stiff
- a Safety, Health and Environmental, Altria Client Services Inc. , Richmond , Virginia
| | - Patrick D Lilly
- a Safety, Health and Environmental, Altria Client Services Inc. , Richmond , Virginia
| | | | | | - Mohamadi A Sarkar
- b Regulatory Affairs, Altria Client Services Inc. , Richmond , Virginia
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17
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Borreani G, Piano S, Tabacco E. Aerobic stability of maize silage stored under plastic films with different oxygen permeability. J Sci Food Agric 2014; 94:2684-2690. [PMID: 24610004 DOI: 10.1002/jsfa.6609] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 01/28/2014] [Accepted: 02/03/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND The most important factor that can influence silage quality is the degree of anaerobiosis maintained during conservation. The quality of the plastic film is a key factor, since the permeability of polyethylene to oxygen is too high for silage conservation. The aim of this work was to assess the effects of the interaction between three plastic films with different degrees of oxygen permeability and two different maize silage conservation times on fermentation, microbial quality and aerobic stability. RESULTS The conservation time affected the pH, lactic and acetic acids, 1,2-propanediol and lactic/acetic acid ratio, with higher pH, lower lactic acid concentration and lactic/acetic acid ratio but higher acetic acid and 1,2-propanediol concentrations being found in silages conserved for 110 days versus silages conserved for 55 days. The plastic film affected the pH, lactic and acetic acids and lactic/acetic acid ratio. The yeast count was lower and aerobic stability higher for silage conserved under the oxygen barrier film for both conservation periods. CONCLUSION The positive interaction between length of storage and the increased anaerobiosis of silage during conservation provided by the oxygen barrier compared with polyethylene film helped reduce the yeast count and increase the aerobic stability of maize silage, even when less acetic acid was produced during ensiling.
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Affiliation(s)
- Giorgio Borreani
- Department of Agricultural, Forest and Food Sciences (DISAFA), University of Torino, Via Leonardo da Vinci 44, I-10095, Grugliasco, Italy
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18
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Tøttenborg SS, Holm AL, Wibholm NC, Lange P. [E-cigarettes also contain detrimental chemicals]. Ugeskr Laeger 2014; 176:V03140161. [PMID: 25293843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This article reviews studies dealing with the content of electronic (e-) cigarettes. Based on measurements of the e-juice, the inhaled and the exhaled vapour, it is sound to assume that smoking e-cigarettes might have much less detrimental health effects than smoking conventional cigarettes. However, propylene glycol and glycerine are abundant in e-cigarettes and although they are generally perceived as relatively harmless, the long-term effects of heavy exposure to these substances are unknown.
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19
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Burstyn I. Peering through the mist: systematic review of what the chemistry of contaminants in electronic cigarettes tells us about health risks. BMC Public Health 2014; 14:18. [PMID: 24406205 PMCID: PMC3937158 DOI: 10.1186/1471-2458-14-18] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 01/02/2014] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Electronic cigarettes (e-cigarettes) are generally recognized as a safer alternative to combusted tobacco products, but there are conflicting claims about the degree to which these products warrant concern for the health of the vapers (e-cigarette users). This paper reviews available data on chemistry of aerosols and liquids of electronic cigarettes and compares modeled exposure of vapers with occupational safety standards. METHODS Both peer-reviewed and "grey" literature were accessed and more than 9,000 observations of highly variable quality were extracted. Comparisons to the most universally recognized workplace exposure standards, Threshold Limit Values (TLVs), were conducted under "worst case" assumptions about both chemical content of aerosol and liquids as well as behavior of vapers. RESULTS There was no evidence of potential for exposures of e-cigarette users to contaminants that are associated with risk to health at a level that would warrant attention if it were an involuntary workplace exposures. The vast majority of predicted exposures are < <1% of TLV. Predicted exposures to acrolein and formaldehyde are typically <5% TLV. Considering exposure to the aerosol as a mixture of contaminants did not indicate that exceeding half of TLV for mixtures was plausible. Only exposures to the declared major ingredients--propylene glycol and glycerin--warrant attention because of precautionary nature of TLVs for exposures to hydrocarbons with no established toxicity. CONCLUSIONS Current state of knowledge about chemistry of liquids and aerosols associated with electronic cigarettes indicates that there is no evidence that vaping produces inhalable exposures to contaminants of the aerosol that would warrant health concerns by the standards that are used to ensure safety of workplaces. However, the aerosol generated during vaping as a whole (contaminants plus declared ingredients) creates personal exposures that would justify surveillance of health among exposed persons in conjunction with investigation of means to keep any adverse health effects as low as reasonably achievable. Exposures of bystanders are likely to be orders of magnitude less, and thus pose no apparent concern.
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Affiliation(s)
- Igor Burstyn
- Department of Environmental and Occupational Health, School of Public Health, Drexel University, Nesbitt Hall, 3215 Market St, Floor 6, Office 614, Philadelphia, PA 19104, USA.
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20
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Wehrer M, Jaesche P, Totsche KU. Modeling the kinetics of microbial degradation of deicing chemicals in porous media under flow conditions. Environ Pollut 2012; 168:96-106. [PMID: 22609860 DOI: 10.1016/j.envpol.2012.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 04/06/2012] [Accepted: 04/09/2012] [Indexed: 06/01/2023]
Abstract
A quantitative knowledge of the fate of deicing chemicals in the subsurface can be provided by joint analysis of lab experiments with numerical simulation models. In the present study, published experimental data of microbial degradation of the deicing chemical propylene glycol (PG) under flow conditions in soil columns were simulated inversely to receive the parameters of degradation. We evaluated different scenarios of an advection-dispersion model including different terms for degradation, such as zero order, first order and inclusion of a growing and decaying biomass for their ability to explain the data. The general break-through behavior of propylene glycol in soil columns can be simulated well using a coupled model of solute transport and degradation with growth and decay of biomass. The susceptibility of the model to non-unique solutions was investigated using systematical forward and inverse simulations. We found that the model tends to equifinal solutions under certain conditions.
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Affiliation(s)
- Markus Wehrer
- Institute of Geosciences, Friedrich Schiller University of Jena, Burgweg 11, 07743 Jena, Germany.
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21
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Schubert J, Hahn J, Dettbarn G, Seidel A, Luch A, Schulz TG. Mainstream smoke of the waterpipe: does this environmental matrix reveal as significant source of toxic compounds? Toxicol Lett 2011; 205:279-84. [PMID: 21712083 DOI: 10.1016/j.toxlet.2011.06.017] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 06/10/2011] [Accepted: 06/14/2011] [Indexed: 10/18/2022]
Abstract
In recent years the number of waterpipe smokers has increased substantially worldwide. Here we report on the concentrations of tobacco-specific nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) in waterpipe smoke and the analysis of selected biomarkers indicative for the body burden in waterpipe users. We further identify high amounts of unburned humectants (glycerol and propylene glycol) in the waterpipe smoke as main part of the so-called "tar" fraction. These results give cause for serious concern. For standardization we applied a machine smoking protocol. Smoke was collected on glass fiber filters and analyzed for nicotine, water, humectants, TSNAs, and PAHs. In addition, we determined carbon monoxide and found high amounts in the smoke being causative for high levels of carboxyhemoglobin (COHb) in the blood of smokers. In comparison to the reference cigarette 3R4F, the nicotine contents were 10-times higher, but TSNA levels were found lower in waterpipe smoke. This finding explained the low levels of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol detected in the urine of waterpipe smokers. Finally, the levels of benzo[a]pyrene were three times higher in waterpipe smoke compared to the reference cigarette. Altogether, the data presented in this study point to the health hazards associated with the consumption of waterpipes.
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Affiliation(s)
- Jens Schubert
- German Federal Institute for Risk Assessment (BfR), Department of Product Safety, Thielallee 88-92, 14195 Berlin, Germany.
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22
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Tsao YC, Wu CF, Chang PE, Chen SY, Hwang YH. Efficacy of using multiple open-path Fourier transform infrared (OP-FTIR) spectrometers in an odor emission episode investigation at a semiconductor manufacturing plant. Sci Total Environ 2011; 409:3158-3165. [PMID: 21621818 DOI: 10.1016/j.scitotenv.2011.04.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 04/20/2011] [Accepted: 04/27/2011] [Indexed: 05/30/2023]
Abstract
This study evaluated the efficacy of simultaneously employing three open-path Fourier transform infrared (OP-FTIR) spectrometers with 3-day consecutive monitoring, using an odor episode as an example. The corresponding monitoring paths were allocated among the possible emission sources of a semiconductor manufacturing plant and the surrounding optoelectronic and electronic-related factories, which were located in a high-tech industrial park. There was a combined total odor rate of 43.9% for the three monitoring paths, each comprised of 736 continuous 5-minute monitoring records and containing detectable odor compounds, such as ammonia, ozone, butyl acetate, and propylene glycol monomethyl ether acetate (PGMEA). The results of the logistic regression model indicated that the prevailing south wind and the OP-FTIR monitoring path closest to the emission source in down-wind direction resulted in a high efficacy for detecting odorous samples with odds ratios (OR) of 3.8 (95% confidence interval (CI): 2.9-5.0) and 5.1 (95% CI: 3.6-7.2), respectively. Meanwhile, the odds ratio for detecting ammonia odorous samples was 7.5 for Path II, which was downwind closer to the possible source, as compared to Path III, downwind far away from the possible source. PGMEA could not be monitored at Path II but could be at Path III, indicating the importance of the monitoring path and flow ejection velocities inside the stacks on the monitoring performance of OP-FTIR. Besides, an odds ratio of 5.1 for odorous sample detection was obtained with south prevailing wind comprising 65.0% of the monitoring time period. In general, it is concluded that OP-FTIR operated with multiple paths simultaneously shall be considered for investigation on relatively complicated episodes such as emergency of chemical release, multiple-source emission and chemical monitoring for odor in a densely populated plant area to enhance the efficacy of OP-FTIR monitoring.
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Affiliation(s)
- Yung-Chieh Tsao
- Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University College of Public Health, Taipei City 100, Taiwan
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23
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Molever K. Simplified assay of diethylene glycol and ethylene glycol in various raw materials by capillary gas chromatography. J Cosmet Sci 2010; 61:225-234. [PMID: 20587351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Accepted: 11/16/2009] [Indexed: 05/29/2023]
Abstract
The FDA has recently taken steps to reduce risks due to raw materials affected by economically motivated adulteration (EMA). One area of great interest is diethylene glycol (DEG) or ethylene glycol (EG) adulteration of glycerin, propylene glycol, and solutions of sorbitol, for which the USP monographs have recently been revised (1). Such adulterations have occurred many times and in many countries, including a tragic episode between November 2008 and January 2009 in which 84 children in Nigeria died after ingesting teething syrup contaminated with DEG (9,10). To eliminate this problem, the FDA has required manufacturers of finished products to assay and confirm that incoming glycerin, propylene glycol, and sorbitol solutions meet the USP limits, and the FDA/USP has incorporated such testing into the identity requirements of its updated monographs.Unfortunately, even though USP test procedures detail a simultaneous DEG and EG assay for these materials, different standard solutions are specified depending upon whether the incoming sample is glycerin, propylene glycol, or a sorbitol solution; in addition, a certain gas chromatography (GC) capillary phase is detailed for sorbitol solutions, while the assays for glycerin and propylene glycol use a different capillary phase, requiring column changeovers, separate GC systems, or front/rear column configuration. In addition, NF monographs for polyethylene glycols (PEG) and polyethylene glycol monomethyl ethers (MPEG) used in pharmaceutical products also require DEG and EG testing (detailing their own specific tests); three separate test procedures for these types of raw materials (the larger PEG-type polymers are assayed differently than their smaller counterparts), making assay at QC unwieldy.This paper describes a single, simple test procedure that is applicable to the simultaneous assay of DEG and EG in all types of the described raw materials, using one standard solution. The assay procedure involves straightforward isolation, trimethylsilylation, and simultaneous capillary gas chromatographic quantitation using capillary GC with flame ionization detection. Although the USP-NF limits are 0.10% DEG and 0.10% EG (and 0.25% total DEG plus EG for the PEG and MPEG products), in reality any EMA would be at levels significantly higher than that, as low-level illegal EMA would not be economically advantageous. The scope of this project was not to fully validate this technique for inclusion in USP-NF, but just to demonstrate its applicability for those wishing to utilize it or take it further.
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Affiliation(s)
- K Molever
- Research and Development Department, The Dial Corporation, a Henkel Company, Scottsdale, AZ 85255, USA
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Zhou T, Zhang H, Duan G. Simultaneous determination of diethylene glycol and propylene glycol in pharmaceutical products by HPLC after precolumn derivatization with p-toluenesulfonyl isocyanate. J Sep Sci 2008; 30:2620-7. [PMID: 17880028 DOI: 10.1002/jssc.200700097] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A simple and reliable HPLC method was developed for the simultaneous quantitative analysis of diethylene glycol (DEG) and propylene glycol (PG) in pharmaceutical products by precolumn derivatization. The derivatization reagent p-toluenesulfonyl isocyanate (TSIC, 10 microL, 20% in ACN v/v) was added to 100 microL of the sample, and then 10 muL of water was added. The resulting derivatives were separated using a C(18)analytical column and a mobile phase composed of 0.01 M KH(2)PO(4)buffer (adjusted to pH 2.5 with phosphoric acid) and ACN (47:53 v/v) at 1 mL/min and 25 degrees C. For detection, UV light at 227 nm was used. The derivatization conditions including reaction time, temperature, and concentration of TSIC were optimized. The calibration curves were linear from 0.062 to 18.6 microg/mL (r(2)= 0.9999) and from 0.071 to 21.3 microg/mL (r(2) = 0.9999) for DEG and PG, respectively. The RSD values of intra- and interday assays were all below 4% for DEG and PG. The proposed method was then successfully applied to analyze two Armillarisin A injection samples and two spiked syrup samples.
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Affiliation(s)
- Tao Zhou
- Department of Pharmaceutical Analysis, School of Pharmacy, Fudan University, Shanghai, PR China
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Coloe J, Zirwas MJ. Allergens in corticosteroid vehicles. Dermatitis 2008; 19:38-42. [PMID: 18346395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND Whereas allergy to vehicle ingredients (ie, excipients and preservatives) in topical steroid vehicles is well recognized, there are no data regarding which vehicle ingredients are in common use or on which vehicles and active molecules are associated with which ingredients. OBJECTIVE To produce descriptive data on the use of allergenic vehicle ingredients in prescription topical corticosteroids. METHODS The package insert for every steroid in widespread use in the United States was obtained from the manufacturer and used to generate an ingredient list for the product. RESULTS There are seven vehicle ingredients that are commonly used in topical corticosteroid vehicles that are well-known allergens: propylene glycol, sorbitan sesquioleate, formaldehyde-releasing preservatives, parabens, methylchloroisothiazolinone/methylisothiazolinone, lanolin, and fragrance. Of 166 topical corticosteroids, 128 (including all creams) had at least one of these vehicle ingredients. More generic products were free of allergens than were branded products. Solutions and ointments were the least allergenic vehicles. The most commonly present potential allergens were propylene glycol and sorbitan sesquioleate. CONCLUSIONS Most prescription topical corticosteroids have the potential to cause allergic contact dermatitis owing to vehicle ingredients. Dermatologists should be aware of this possibility and should consider prescribing agents that do not contain potentially allergenic vehicle ingredients.
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Affiliation(s)
- Jacquelyn Coloe
- Ohio State University College of Medicine, Columbus, OH 43210, USA
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Abstract
Tissue-on-tissue friction testing was used to determine how instillation of hydrophilic polymer-containing formulations between the "blinking" tissues would compare with lubrication by saline, alone, or an oil-emulsion preparation. Best results were obtained for a formulation that contained active demulcents polyethylene glycol (PEG 400) and propylene glycol (PG), as well as a gellable polymer hydroxypropyl guar (HP-Guar) in a borate-buffered solution, in comparison with hydroxypropylcellulose-containing and carboxymethylcellulose-containing formulations. Superior performance of all the formulations was found for lubricating tissue-on-tissue couples, compared with metal-oxide-to-metal oxide interfaces, or metal oxide-to-tissue interfaces. A reciprocating pin-on-disc type friction/wear test device articulated the intimal faces of preserved human umbilical cord vein segments under increasing loads during simulated continuous "eye-blinking" with addition of increasing weights up to 60 g/cm2, simulating maximal eyelid force on the orbital globe. The tissue-on-tissue couples moved from liquid phase lubrication to boundary lubrication. After residual formulations were rinsed away with saline, persistence of low friction at the highest loads was indicative of formulation substantivity. Human umbilical cord vein segments were utilized in saline-wetted tissue-on-tissue couples that showed variable starting coefficients of friction in the range 0.2-0.4, producing moderate tearing and disruption of the interfacial layers above the medial collagen zone. The best-performing formulations instilled to the tissues pre-wetted with saline apparently reacted separately with each tissue face to produce a lower final and persistent coefficient of friction of about 0.05. Scanning electron microscopy and light microscopy of these guar-modified tissue specimens showed only a few superficial tissue disruptions, and some interphase swelling consistent with polymer uptake. The frictional values for lubricated couples having non-tissue members were considerably higher than the coefficients of friction measured for the similarly lubricated tissue-on-tissue couples, emphasizing the requirement that appropriate simulations are critical to obtaining clinically predictive data.
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Affiliation(s)
- Anne E Meyer
- Industry/University Center for Biosurfaces, University at Buffalo, Buffalo, New York 14214-3007, USA
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West RJ, Davis JW, Pottenger LH, Banton MI, Graham C. Biodegradability relationships among propylene glycol substances in the Organization for Economic Cooperation and Development ready- and seawater biodegradability tests. Environ Toxicol Chem 2007; 26:862-71. [PMID: 17521130 DOI: 10.1897/06-327r.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Eight propylene glycol substances, ranging from 1,2-propanediol to a poly(propylene glycol) (PPG) having number-average molecular weight (M(n)) of 2,700 (i.e., PPG 2700), were evaluated in the Organization for Economic Cooperation and Development (OECD) ready- and seawater biodegradability tests. Uniformity in test parameters, such as inoculum source/density and test substance concentrations, combined with frequent measurements of O2 consumption and CO2 evolution, revealed unexpected biodegradability trends across this family of substances. Biodegradability in both tests decreased with increased number of oxy-propylene repeating units (n = 1, 2, 3, 4) of the oligomeric propylene glycols (PGs). However, this trend was reversed for the PPG polymers, and increased biodegradability was observed with increases of average n to seven, 17, and 34 (M(n) = 425, 1,000, and 2,000, respectively). This relationship between molecular weight and biodegradability was reversed again when average n was incremented from 34 (PPG 2000) to 46 (PPG 2700). Six of the tested substances (n = 1, 2, 3, 7, 17, and 34) met the OECD-specified criteria for "ready biodegradability," whereas the tetrapropylene glycol (n = 4) and PPG 2700 substances failed to meet these criteria. Biodegradation half-lives for these eight substances ranged from 3.8 d (PPG 2000) to 33.2 d (PPG 2700) in the ready test, and from 13.6 (PG) to 410 d (PPG 2700) in seawater. Biodegradation half-lives in seawater were significantly correlated with half-lives determined in the ready test. However, half-lives in both tests were correlated poorly with molecular weight, water solubility, and log K(ow). It is speculated that the molecular conformation of these substances, perhaps more so than these other physicochemical properties, has an important role in influencing biodegradability of the propylene glycol substances.
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Affiliation(s)
- Robert J West
- Toxicology & Environmental Research and Consulting, The Dow Chemical Company, 1803 Building, Midland, Michigan 48674, USA.
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Sharma R, Law GK, Rekieh K, Abazari A, Elliott JAW, McGann LE, Jomha NM. A novel method to measure cryoprotectant permeation into intact articular cartilage. Cryobiology 2007; 54:196-203. [PMID: 17379205 DOI: 10.1016/j.cryobiol.2007.01.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 11/24/2006] [Accepted: 01/11/2007] [Indexed: 10/23/2022]
Abstract
Successful cryopreservation of articular cartilage (AC) could improve clinical results of osteochondral allografting and provide a useful treatment alternative for large cartilage defects. However, successful cartilage cryopreservation is limited by the time required for cryoprotective agent (CPA) permeation into the matrix and high CPA toxicity. This study describes a novel, practical method to examine the time-dependent permeation of CPAs [dimethyl sulfoxide (DMSO) and propylene glycol (PG)] into intact porcine AC. Dowels of porcine AC (10 mm diameter) were immersed in solutions containing high concentrations of each CPA for different times (0, 15, 30, 60 min, 3, 6, and 24 h) at three temperatures (4, 22, and 37 degrees C), with and without cartilage attachment to bone. The cartilage was isolated and the amount of cryoprotective agent within the matrix was determined. The results demonstrated a sharp rise in the CPA concentration within 15-30 min exposure to DMSO and PG. The concentration plateaued between 3 and 6 h of exposure at a concentration approximately 88-99% of the external concentration (6.8 M). This observation was temperature-dependent with slower permeation at lower temperatures. This study demonstrated the effectiveness of a novel technique to measure CPA permeation into intact AC, and describes permeation kinetics of two common CPAs into intact porcine AC.
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Affiliation(s)
- Rajrishi Sharma
- Department of Surgery, University of Alberta Hospital, 2D2.32 WMC, 8440-112St, Edmonton, Alta., Canada T6G 2B7
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Affiliation(s)
- Alexander V Kuznetsov
- Klinik und Poliklinik für Dermatologie und Allergologie, Ludwig-Maximilians-Universität München, Munich, Germany.
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Abstract
The preparation of nonaqueous microemulsions using food-acceptable components is reported. The effect of oil on the formation of microemulsions stabilized by lecithin (Epikuron 200) and containing propylene glycol as immiscible solvent was investigated. When the triglycerides were used as oil, three types of phase behavior were noted, namely, a two-phase cloudy region (occurring at low lecithin concentrations), a liquid crystalline (LC) phase (occurring at high surfactant and low oil concentrations), and a clear monophasic microemulsion region. The extent of this clear one-phase region was found to be dependent upon the molecular volume of the oil being solubilized. Large molecular volume oils, such as soybean and sunflower oils, produced a small microemulsion region, whereas the smallest molecular volume triglyceride, tributyrin, produced a large, clear monophasic region. Use of the ethyl ester, ethyl oleate, as oil produced a clear, monophasic region of a size comparable to that seen with tributyrin. Substitution of some of the propylene glycol with water greatly reduced the extent of the clear one-phase region and increased the extent of the liquid crystalline region. In contrast, ethanol enhanced the clear, monophasic region by decreasing the LC phase. Replacement of some of the lecithin with the micelle-forming nonionic surfactant Tween 80 to produce mixed lecithin/Tween 80 mixtures of weight ratios (Km) 1:2 and 1:3 did not significantly alter the phase behavior, although there was a marginal increase in the area of the two-phase, cloudy region of the phase diagram. The use of the lower phosphatidylcholine content lecithin, Epikuron 170, in place of Epikuron 200 resulted in a reduction in the LC region for all of the systems investigated. In conclusion, these studies show that it is possible to prepare one-phase, clear lecithin-based microemulsions over a wide range of compositions using components that are food-acceptable.
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Affiliation(s)
- Nilesh Patel
- Pharmaceutical Science Research Division, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
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Abstract
The effect of inoculating whole-plant corn at the time of harvest with Lactobacillus buchneri 40788 (4 x 10(5) cfu/g of fresh forage) combined with Pediococcus pentosaceus R1094 (1 x 10(5) cfu/g) on the fermentation and aerobic stability of corn silage (37% dry matter) through 361 d of ensiling was investigated. Dry matter recovery was similar between treatments throughout the study except at one early time point (14 d), when treated silage had a lower recovery than untreated silage. The concentration of lactic acid was unaffected by inoculation but inoculated silages had greater concentrations of 1,2-propanediol and acetic acid from 56 to 361 d of storage. In general, inoculation decreased the concentration of water-soluble carbohydrates but increased the concentration of ethanol. The numbers of yeasts was lower in inoculated silage at 42, 56, 70, and 282 d of ensiling. However, inoculation did not consistently improve the aerobic stability of silage, suggesting that microbes other than yeasts may have been responsible for aerobic instability in this study. Even after prolonged storage (361 d), silage treated with L. buchneri 40788 and P. pentosaceus R1094 had normal silage fermentation characteristics.
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Affiliation(s)
- D H Kleinschmit
- Department of Animal and Food Sciences University of Delaware, Newark, Delaware 19716-2150, USA
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Jaesche P, Totsche KU, Kögel-Knabner I. Transport and anaerobic biodegradation of propylene glycol in gravel-rich soil materials. J Contam Hydrol 2006; 85:271-86. [PMID: 16563561 DOI: 10.1016/j.jconhyd.2006.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 02/01/2006] [Accepted: 02/07/2006] [Indexed: 05/08/2023]
Abstract
Continued input of airplane de-icing/anti-icing fluids (ADAF) to runway adjacent soils may result in the depletion of soil-borne terminal electron acceptors. We studied the transport and transformation of propylene glycol (PG), the major constituent of many ADAF, in topsoil and subsoil samples using saturated column experiments at 4 degrees C and 20 degrees C. The export of soil-borne DOC was generally high, non-exhaustive and rate limited. Retardation of added PG was negligible. Rapid PG degradation was observed only in topsoil materials high in organic matter at 20 degrees C. At 4 degrees C, no significant degradation was observed. Thus, under unfavorable, i.e., wet and cold conditions typical for winter de-icing operations, PG and its metabolites will be relocated to deeper soil horizons or even to the groundwater. In subsoil materials, PG degradation was very slow and incomplete. We found that subsoil degradation depended on the import of active microorganisms originating from the organic-rich topsoil material. The degradation efficiency is strongly influenced by the flow velocity, i.e., the residence time of PG in the soil column. Poorly crystalline iron(III) and manganese(IV) (hydr)oxides are used during microbial respiration acting as terminal electron acceptors. This results in the formation and effective relocation of reduced and mobile Fe and Mn species. Long-term application of ADAF to runway adjacent soil as well as the lasting consumption of Fe and Mn will tend to decrease the soil redox potential. Without proper counteractive measures, this will eventually favor the development of methanogenic conditions.
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Affiliation(s)
- Philipp Jaesche
- Lehrstuhl für Bodenkunde, Department für Okologie, Technische Universität München, 85350 Freising-Weihenstephan, Germany
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Kramer A, Galabov AS, Sattar SA, Döhner L, Pivert A, Payan C, Wolff MH, Yilmaz A, Steinmann J. Virucidal activity of a new hand disinfectant with reduced ethanol content: comparison with other alcohol-based formulations. J Hosp Infect 2005; 62:98-106. [PMID: 16307826 PMCID: PMC7132428 DOI: 10.1016/j.jhin.2005.06.020] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 06/07/2005] [Indexed: 10/25/2022]
Abstract
A new formula with reduced ethanol content (55%) in combination with 10% propan-1-ol, 5.9% propan-1.2-diol, 5.7% butan-1.3-diol and 0.7% phosphoric acid exhibited a broad spectrum of virucidal activity. In quantitative suspension tests, with and without protein load, this formulation reduced the infectivity titre of seven enveloped (influenza A and B, herpes simplex 1 and 2, bovine corona, respiratory syncytial, vaccinia, hepatitis B, bovine viral diarrhoea) and four non-enveloped (hepatitis A, polio, rota, feline calici) viruses >10(3)-fold within 30s. In comparative testing, only 95% ethanol showed similar levels of activity. In fingerpad tests, the formulation produced a log10 reduction factor of the titre of poliovirus type 1 (Sabin) of 3.04 in 30s compared with 1.32 by 60% propan-2-ol. Testing against feline calicivirus produced a log10 reduction factor of 2.38 by the test formulation; in contrast, the log10 reduction factors with 70% ethanol and 70% propan-1-ol were 0.68 and 0.70, respectively.
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Affiliation(s)
- A Kramer
- Institute of Hygiene and Environmental Medicine, Ernst Moritz Arndt University Greifswald, Walther Rathenau Str. 49a, 17489 Greifswald, Germany.
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Savin GA, Kutsemako OM. [The synthesis of thio- and selenoanalogues of phospholipids on the basis of 2-butyl-2-hydroxymethyl-1,3-propanediol]. Bioorg Khim 2005; 31:414-9. [PMID: 16119461 DOI: 10.1007/s11171-005-0051-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
New analogues of nonglycerol polyol phospholipids were prepared on the basis of 1,1,1-trimethylolethane. Amidophosphites and cyclophosphites of the isopropylidene derivative of this polyol were intermediates in the syntheses. They were treated with sulfur or selenium. Phosphoacetals were converted into lipids by the direct acylation with higher fatty acid chlorides. The triol bicyclophosphite was also used in the lipid syntheses. It was directly acylated at the oxygen atom, the resulting acylpolyol of chlorophosphite was then converted into phospholipids by alcoholysis and subsequent treatment with sulfur.
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Abstract
BACKGROUND/PURPOSE Thermal emission decay-Fourier transform infrared (TED-FTIR) spectroscopy is a non-contact and non-destructive analytical technique and was used in this study to detect the presence of external chemicals on human skin in vivo. The detection was possible due to the ability of the TED-FTIR technique to acquire the mid-infrared spectrum of the outmost layers (less than 10 microm) of Stratum Corneum (SC) and the ability to identify the absorption bands of the chemical. METHODS As an illustration of such measurements, propylene glycol (PG) was applied on human stratum corneum and depth-resolved TED-FTIR spectra of the SC were measured to quantify the concentration of PG in deeper layers of SC. RESULTS The mid-infrared spectrum of the surface 0.7 microm layer of skin had 50% contribution from SC and 50% from PG. At 3 h after application, the contribution of PG at the surface decreased to 7% as PG molecules diffused deeper into the skin and were lost at the surface. At a depth of 6 microm, the maximum concentration was 20% after 25 min after PG application. CONCLUSIONS This work shows the feasibility of the TED-FTIR technique to detect the presence of chemicals on human SC in vivo and without contact, and for a wide range of other applications, such as detection of toxic chemicals used as warfare (vesicant agents like sulphur mustard and organophosphate nerve agents), pesticides, and other toxins on fruit and vegetable skins, water, or even other contaminated surfaces.
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Affiliation(s)
- Ioan Notingher
- Photophysics Research Centre, London South Bank University, London, UK.
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Zhu J, Feng YL, Aikawa B. A positive chemical ionization GC/MS method for the determination of airborne ethylene glycol and propylene glycols in non-occupational environments. ACTA ACUST UNITED AC 2004; 6:881-7. [PMID: 15536501 DOI: 10.1039/b408635j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An analytical method for ethylene glycol and propylene glycols has been developed for measuring airborne levels of these chemicals in non-occupational environments such as residences and office buildings. The analytes were collected on charcoal tubes, solvent extracted, and analyzed by gas chromatography-mass spectrometry using a positive chemical ionization technique. The method had a method detection limit of 0.07 microg m(-3) for ethylene glycol and 0.03 microg m(-3) for 1,2- and 1,3-propylene glycols, respectively, based on a 1.44 m3 sampling volume. Indoor air samples of several residential homes and other indoor environments have been analyzed. The median concentrations of ethylene glycol and 1,2-propylene glycol in nine residential indoor air samples were 53 microg m(-3) and 13 microg m(-3) respectively with maximum values of 223 microg m(-3) and 25 microg m(-3) detected for ethylene glycol and 1,2-propylene glycol respectively. The concentrations of these two chemicals in one office and two laboratories were at low microg m(-3) levels. The maximum concentration of 1,3-propylene glycol detected in indoor air was 0.1 microg m(-3).
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Affiliation(s)
- Jiping Zhu
- Chemistry Research Division, Health Canada, AL: 0800C, EHC Building, Tunney's Pasture, Ottawa, Canada K1A 0L2.
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Renom G, Maisonneuve N, Kim I, Dehon B, Azar R. Major ketogenesis and the absence of an osmolar gap in an atypical case of alcoholic ketoacidosis. Ann Clin Biochem 2003; 40:424-6. [PMID: 12880548 DOI: 10.1258/000456303766477110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A new case of alcoholic ketoacidosis (AKA) is presented because of unusual clinical and biochemical features. Although it shares some similarities with typical cases of AKA, it appears as unique because of predominantly neurological, rather than abdominal symptoms, major ketogenesis with normal ketone body ratio, the presence of large amounts of propanediol and the absence of an osmolar gap.
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Affiliation(s)
- G Renom
- Laboratoire de Biochimie et de Biologie Moléculaire, Hôpital Huriez, Lille, France.
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Ishiwata H, Nishijima M, Fukasawa Y. Estimation of inorganic food additive (nitrite, nitrate and sulfur dioxide), antioxidant (BHA and BHT), processing agent (propylene glycol) and sweetener (sodium saccharin) concentrations in foods and their daily intake based on official inspection results in Japan in fiscal year 1998. Shokuhin Eiseigaku Zasshi 2003; 44:132-43. [PMID: 12846162 DOI: 10.3358/shokueishi.44.132] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The mean concentration and daily intake of inorganic food additives (nitrite, nitrate, and sulfur dioxide), antioxidants (BHA and BHT), a processing agent (propylene glycol), and a sweetener (sodium saccharin) were estimated based on the results of an analysis of 34,489 food samples obtained in official inspections by 106 local governments in Japan in fiscal year 1998. The ratios of mean concentrations of these seven food additives to each allowable limit were 20.0%, 53.9%, 15.5%, 6.2%, 0.4%, 18.5%, and 5.7%, respectively. The daily intakes of these food additives estimated from their concentrations in foods and the daily consumption of foods were 0.205, 0.532, 4.31, 0.119, 0.109, 77.5, and 7.27 mg per person, respectively. These amounts were 6.8%, 0.3%, 12.3%, 0.5%, 0.7%, 6.2%, and 2.6% of the acceptable daily intake (ADI), respectively, when body weight was assumed to be 50 kg. No remarkable differences in the daily intakes of these seven food additives or the ratios to the ADI were observed compared with the results based on the official inspections in fiscal years 1994 and 1996.
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Affiliation(s)
- Hajimu Ishiwata
- National Institute of Health Sciences, Osaka Branch: 1-1-43, Hoenzaka, Chuo-ku, Osaka 540-0006, Japan
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Matsumoto H, Ogawa H, Suzuki K, Suzuki J, Yasuda K. [Simultaneous analysis of four kinds of emulsifiers in beverages by GC/MS]. Shokuhin Eiseigaku Zasshi 2003; 44:19-25. [PMID: 12749192 DOI: 10.3358/shokueishi.44.19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An analytical method using GC/MS for the detection of 4 kinds of dietary emulsifiers, glycerin, sucrose, sorbitan and propylene glycol monoesters of fatty acids (GE, SuE, SE, PGE), in beverages was developed. The emulsifiers were extracted from beverages with tetrahydrofuranethyl acetate (6:4) by homogenizing. The extract was cleaned up on a silica gel column and subsequently a C8 cartridge column, followed by acetylation. The derivatives were then detected by GC/MS. Our newly established method enabled to characterize 4 kinds of emulsifiers and also to identify their fatty acids without hydrolysis or de-esterification. When this method was applied to various beverages on the market, many GE and SuE with different fatty acids were detected. These results suggested that several dietary emulsifiers are used as food additives at the same time in beverages on the market.
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Affiliation(s)
- Hiroko Matsumoto
- Tama Branch Laboratory, Tokyo Metropolitan Research Laboratory of Public Health: 3-16-25, Shibasaki-cho, Tachikawa, Tokyo 190-0023, Japan
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Endris RG, Everett R, Cunningham J, Katz TL, Thompson K. Efficacy of two 65 % permethrin spot-on formulations against canine infestations of Ctenocephalides felis and Rhipicephalus sanguineus. Vet Ther 2003; 3:326-33. [PMID: 12447841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
The efficacy of two formulations of a topically applied 65% permethrin spot-on for dogs (Defend EXspot Treatment for Dogs, Schering-Plough Animal Health Corp.) was evaluated against experimental infestations of the cat flea, Ctenocephalides felis, and the brown dog tick, Rhipicephalus sanguineus. Thirty dogs were randomly allocated to treatment with 65 % permethrin in diethylene glycol monomethyl ether (original formulation), 65 % permethrin in propylene glycol monomethyl ether (test formulation), or to an untreated control group. Dogs assigned to treatment with a permethrin formulation received either 1 or 2 ml of the formulation in accordance with label directions on Day 0. One hundred unfed, adult cat fleas and 50 unfed, adult ticks were placed on each dog on Days -1, 5, 12, 19, 26, 33, and 40. Live fleas and ticks were counted on each dog on Days 2, 7, 14, 21, 28, 35, and 42. Treatment of dogs with either formulation of 65 % permethrin significantly (P <.05) reduced the number of live fleas and ticks from Days 2 through 42. No statistical differences were noted between the formulations regarding efficacy against C. felis or R. sanguineus.
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Blackledge RD. Commentary on: Lee GSH, Brinch KM, Kannangara K, Dawson M, Wilson MA. A methodology based on NMR spectroscopy for the forensic analysis of condoms. J Forensic Sci 2002; 47:429-31. [PMID: 11908631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Abstract
The selected ion flow tube mass spectrometry (SIFT-MS) technique enables real time analysis of trace volatiles at ppb levels without preconcentration steps or chemical derivatization. Most previous studies of trace compounds on the breath were analyzed using gas chromatography where enhanced detection sensitivity was achieved by concentrating the breath using cryogenic or adsorption trapping techniques. In this paper, we have examined volatile organic substances, isoprene, acetone, ammonia and ethanol in breath before and after smoking a cigarette. It is interesting that isoprene levels increased in all the subjects after smoking one cigarette with a mean increase of 70%. The mean increase for acetone was found to be 22%. In contrast to isoprene, a decreasing ethanol level was observed in all the subjects except one with the negative mean decrease of 28%. Further SIFT-MS studies also have high-lighted some organic substances produced even by unburned cigarettes, US and New Zealand products. Certain US brands have shown much higher levels of volatile species than cigarettes produced in New Zealand.
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Affiliation(s)
- S T Senthilmohan
- Department of Chemical and Process Engineering, University of Canterbury, Christchurch, New Zealand.
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Abstract
With the advent of new regulations concerning aircraft deicing and management of spent aircraft deicing fluids (ADFs), many airports now face the dual challenges of simultaneously maintaining public safety and protecting the environment. This paper provides a theoretical assessment of the potential environmental impact of stormwater runoff and offers detailed current information on alternative deicing fluid application methods and materials, collection and treatment practices.
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Affiliation(s)
- M S Switzenbaum
- Department of Civil and Environmental Engineering, Unirersity of Massachusetts, Amherst 01003, USA.
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Broad NW, Jee RD, Moffat AC, Eaves MJ, Mann WC, Dziki W. Non-invasive determination of ethanol, propylene glycol and water in a multi-component pharmaceutical oral liquid by direct measurement through amber plastic bottles using Fourier transform near-infrared spectroscopy. Analyst 2000; 125:2054-8. [PMID: 11193093 DOI: 10.1039/b006789j] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fourier transform near-infrared (FT-NIR) spectroscopy was used to quantify rapidly the ethanol (34-49% v/v), propylene glycol (20-35% v/v) and water (11-20% m/m) contents within a multi-component pharmaceutical oral liquid by measurement directly through the amber plastic bottle packaging. Spectra were collected in the range 7302-12,000 cm-1 and calibration models set-up using partial least-squares regression (PLSR) and multiple linear regression. Reference values for the three components were measured using capillary gas chromatography (ethanol and propylene glycol) and Karl Fischer (water) assay procedures. The calibration and test sets consisted of production as well as laboratory batches that were made to extend the concentration ranges beyond the natural production variation. The PLSR models developed gave standard errors of prediction (SEP) of 1.1% v/v for ethanol, 0.9% v/v for propylene glycol and 0.3% m/m for water. For each component the calibration model was validated in terms of: linearity, repeatability, intermediate precision and robustness. All the methods produced statistically favourable outcomes. Ten production batches independent of the calibration and test sets were also challenged against the PLSR models, giving SEP values of 1.3% v/v (ethanol), 1.0% v/v (propylene glycol) and 0.2% m/m (water). NIR transmission spectroscopy allowed all three liquid constituents to be non-invasively measured in under 1 min.
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Affiliation(s)
- N W Broad
- Centre for Pharmaceutical Analysis, School of Pharmacy, University of London, 29/39 Brunswick Square, London, UK WC1N 1AX
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Gotvajn AZ, Zagorc-Koncan J. Laboratory simulation of biodegradation of chemicals in surface waters: closed bottle and respirometric test. Chemosphere 1999; 38:1339-1346. [PMID: 10070722 DOI: 10.1016/s0045-6535(98)00535-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Microbial degradation is the most dominant elimination mechanism of organics from the environment. For evaluation of biodegradability of pure chemicals many standardized tests are available, but no standardized procedure for assessment of biodegradability of chemicals in surface water is agreed upon. Rates of in-situ biodegradation are usually estimated in laboratory simulation where environmental factors are reproduced to some extent. The aim of our study was to compare standardised ready biodegradability assessment, test (Closed bottle test) and its modifications employing the basic agreements on test conditions to simulate biodegradation in surface water. Standard test was modified using various natural river waters to simulate the natural environment in a simplified way. The impact of different types and amounts of nutrients and microorganisms on biodegradation was confirmed. The conditions in the recipient should be examined to extrapolate the results from ready biodegradability tests to real surface water.
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Affiliation(s)
- A Z Gotvajn
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, Slovenia
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Abstract
A simple spectrophotometric procedure was developed and validated to indirectly assess the quantities of propylene glycol (PG) remaining in compressed liquid/powder admixtures. Such simplified quantitation may facilitate several testing procedures related to various aspects of formulation development and material testing of pharmaceutical powder excipients using various nonvolatile liquids as the diluents. In the present study, this new and simple approach for PG quantitation was developed as an integral part of a new method termed the liquisolid compressibility (LSC) test, used to characterize the compaction behavior of powder excipients. According to LSC testing, several admixtures of a nonvolatile liquid (in this case PG) and a powder, differing in their PG/powder weight ratio, are compressed in order to assess their compactabilities. The PG content of such compacts may then be directly quantitated by the USP gas chromatographic method or, indirectly, by this new simple spectrophotometric procedure. The new approach involves the addition of a dye marker to the PG prior to its incorporation into the powder. After compression, the PG amount remaining in the compacts may be determined by simply extracting the dye from the tablets and analyzing the extracts spectrophotometrically. In this manner, the dye content thus obtained may be extrapolated to the respective net amount of PG originally added as a dye/PG solution to the powder. Statistical comparison of the results obtained from both methods revealed almost absolute correlation.
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Affiliation(s)
- R Grover
- Division of Pharmaceutics and Industrial Pharmacy, Arnold & Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA
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