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Shuo Wang - One of the best experts on this subject based on the ideXlab platform.

  • Multi-residue determination of organophosphorus and organochlorine pesticides in environmental samples using solid-phase extraction with Cigarette Filter followed by gas chromatography-mass spectrometry
    Journal of Separation Science, 2012
    Co-Authors: Guozhen Fang, Yunping Yao, Junyan Qin, Junping Wang, Wen Bin Chen, Shuo Wang
    Abstract:

    A solid-phase extraction (SPE) method was developed to extract 14 pesticides simultaneously from environment samples using Cigarette Filter as the sorbent before gas chromatography-mass spectrometry (GC-MS) analysis. Parameters influencing the extraction efficiency, such as the sample loading flow rate, eluent and elution volume, were optimized. The optimum sample loading rate was 3 mL/min, and the retained compounds were eluted with 6 mL of eluent at 1 mL/min under vacuum. Good linearity was obtained for all the 14 pesticides (r(2) >0.99) from 0.1 to 20 μg/L for water and from 2 to 400 μg/kg for soil samples. The detection limits (signal-to-noise=3) of the proposed method ranged from 0.01 to 0.20 μg/L for water samples and from 0.42 to 6.95 μg/kg for soil samples. The developed method was successfully applied for determination of the analytes in real environmental samples, and the mean recoveries ranged from 76.4 to 103.7% for water samples and from 79.9 to 105.3% for soil samples with the precisions (relative standard deviation) between 2.0 and 13.6%.

  • Determination of As(III) and As(V) in water samples by flow injection online sorption preconcentration coupled to hydride generation atomic fluorescence spectrometry
    Microchimica Acta, 2009
    Co-Authors: Ning Li, Huaping Zhu, Zhenzhong Gao, Guozhen Fang, Shuo Wang
    Abstract:

    A method was developed for the determination of arsenite [As(III)] and arsenate [As(V)] in water samples using flow injection online sorption coupled with hydride generation atomic fluorescence spectrometry (HG-AFS) using a Cigarette Filter as the sorbent. Selective determination of As(III) was achieved through online formation and retention of the pyrrolidine dithiocarbamate arsenic complex on the Cigarette Filter, but As(V) which did not form complexes was discarded. After reducing As(V) to As(III) using L-cysteine, total arsenic was determined by HG-AFS. The concentration of As(V) was calculated by the difference between As(III) and total arsenic. The analytes were eluted from the sorbent using 1.68 mol L -1 HCl. With consumption of 22 mL of the sample solution, the enrichment factor of As(III) was 25.6. The detection limits (3σ/k) and the relative standard deviation for 11 replicate determinations of 1.0 ng mL -1 As(III) were found to be 7.4 pg mL -1 and 2.6%, respectively. © 2008 Springer-Verlag.

  • Determination of arsenic in foods by flow injection on-line sorption pre-concentration with hydride generation atomic fluorescence spectrometry
    Food Additives and Contaminants - Part A Chemistry Analysis Control Exposure and Risk Assessment, 2009
    Co-Authors: Ning Li, Guozhen Fang, Lei Zhao, Shuai Wang, Shuo Wang
    Abstract:

    A method was developed for the determination of total arsenic in foods using flow injection on-line sorption coupled with hydride generation atomic fluorescence spectrometry (HG-AFS) using a Cigarette Filter as the sorbent material. After reducing As(V) to As(III) by using L-cysteine, the determination of total arsenic was achieved through on-line formation and retention of the pyrrolidine dithiocarbamate arsenic complex (As(III)-PDC) on the Cigarette Filter, which was packed in the pre-concentration column and total arsenic was determined by HG-AFS. The analytes were eluted with 1.68 mol l(-1) HCl from the sorbent material. With consumption of 22 ml of the sample solution, an enrichment factor of 25.6 was obtained at a sample throughput of 11.6 h(-1). The detection limits (3 standard deviations) and the precision (relative standard deviation) in foods ranged from 2.5 to 9.9 ng g(-1) and from 1.1 to 2.2%, respectively. The method was used to determine arsenic in carrot, mushroom, chicken tissue, cod fish, rice, common carp and shrimp.

  • On-line coupling of solid-phase extraction to high-performance liquid chromatography for determination of estrogens in environment
    Analytica Chimica Acta, 2008
    Co-Authors: Shuo Wang, Jinxing He, Guozhen Fang, Wei Huang, Yan Zhang
    Abstract:

    A method based on on-line solid-phase extraction (SPE) coupling to high-performance liquid chromatography (HPLC) for the determination of estrogens has been developed. This method can continuously perform extraction of estrone, estradiol, estriol and diethylstilbestrol from aqueous samples without any other pretreatment, which can then be analyzed by HPLC with a UV detector at 230 nm. A pre-concentration column was adapted with methanol/water for chromatographic separation and two kinds of sorbents were involved, which are octadecyl-bonded silica and Cigarette Filter. The condition of pH of samples, sample loading flow rate and desorption time were all optimized, and the performances of both two sorbents were satisfactory. The on-line SPE system requires very low maintenance and just involved a switching-valve-Filter system and a flow-inject pump, and the operation of the whole SPE-HPLC instrumentation is quite simple. The detection limits for pre-concentrating 50 mL of standard solution using Cigarette Filter as sorbent ranged from 0.98 to 78.1 ng L-1. The enhancement factors were in the range of 197-326. The recoveries of estrogens spiked in real water samples ranged from 85 to 112%. The precisions for nine replicate measurements of a standard mixture (5.0 μg L-1) were in the range of 1.0-3.4%. © 2007 Elsevier B.V. All rights reserved.

Peter G. Shields - One of the best experts on this subject based on the ideXlab platform.

  • Cigarette Filter based assays as proxies for toxicant exposure and smoking behavior a literature review
    Cancer Epidemiology Biomarkers & Prevention, 2009
    Co-Authors: John L. Pauly, Geraldine M. Paszkiewicz, K. M. Cummings, Mirjana V. Djordjevic, R J Oconnor, Peter G. Shields
    Abstract:

    Background: Cigarettes are being marketed with Filters that differ in composition and design. The Filters have different toxicant trapping efficiencies, and smoking stains reflect variations in smoking behavior. Presented herein are the results of a structured literature review that was done to identify Cigarette Filter–based assays that may serve as proxies for mouth-level exposure and assessing smoking methods. Methods: A search of the published scientific literature and internal tobacco company documents from 1954 to 2009 was carried out. Results: The literature search identified diverse schemes for assessing Cigarette Filters, including visual inspection and digital imaging of smoked-stained spent Filters, and quantitative determinations for total particulate matter (TPM), nicotine, and solanesol. The results also showed that: ( a ) there are sufficient data to link Filter-based chemical measures to standardized smoking machine–measured yields of tar and nicotine; ( b ) TPM eluted from Filters or in chemical digest of Filters can be used to estimate the efficiency of the Filter for trapping smoke solids; ( c ) visual and digital inspection of spent Filters is useful in finding indicators of variations in smoking behaviors; and ( d ) there is a correlation between solanesol and nicotine measured in Filters and exposure biomarkers in smokers. Conclusions: The Cigarette Filter may prove useful in estimating smoking behaviors such as Filter vent blocking and puffing intensity, and may have utility as proxy measures of mouth-level smoke exposure in clinical trials. Additional investigations are needed to compare the different proposed assay schemes and the assay results with measurements of human biomarker assays of smoke exposure. (Cancer Epidemiol Biomarkers Prev 2009;18(12):3321–3333)

  • Cigarette Filter-based assays as proxies for toxicant exposure and smoking behavior - A literature review
    Cancer Epidemiology Biomarkers and Prevention, 2009
    Co-Authors: John L. Pauly, Geraldine M. Paszkiewicz, K. M. Cummings, Mirjana V. Djordjevic, Richard J. O'connor, Peter G. Shields
    Abstract:

    BACKGROUND: Cigarettes are being marketed with Filters that differ in composition and design. The Filters have different toxicant trapping efficiencies, and smoking stains reflect variations in smoking behavior. Presented herein are the results of a structured literature review that was done to identify Cigarette Filter-based assays that may serve as proxies for mouth-level exposure and assessing smoking methods.\n\nMETHODS: A search of the published scientific literature and internal tobacco company documents from 1954 to 2009 was carried out.\n\nRESULTS: The literature search identified diverse schemes for assessing Cigarette Filters, including visual inspection and digital imaging of smoked-stained spent Filters, and quantitative determinations for total particulate matter (TPM), nicotine, and solanesol. The results also showed that: (a) there are sufficient data to link Filter-based chemical measures to standardized smoking machine-measured yields of tar and nicotine; (b) TPM eluted from Filters or in chemical digest of Filters can be used to estimate the efficiency of the Filter for trapping smoke solids; (c) visual and digital inspection of spent Filters is useful in finding indicators of variations in smoking behaviors; and (d) there is a correlation between solanesol and nicotine measured in Filters and exposure biomarkers in smokers.\n\nCONCLUSIONS: The Cigarette Filter may prove useful in estimating smoking behaviors such as Filter vent blocking and puffing intensity, and may have utility as proxy measures of mouth-level smoke exposure in clinical trials. Additional investigations are needed to compare the different proposed assay schemes and the assay results with measurements of human biomarker assays of smoke exposure.

John L. Pauly - One of the best experts on this subject based on the ideXlab platform.

  • Cigarette Filter based assays as proxies for toxicant exposure and smoking behavior a literature review
    Cancer Epidemiology Biomarkers & Prevention, 2009
    Co-Authors: John L. Pauly, Geraldine M. Paszkiewicz, K. M. Cummings, Mirjana V. Djordjevic, R J Oconnor, Peter G. Shields
    Abstract:

    Background: Cigarettes are being marketed with Filters that differ in composition and design. The Filters have different toxicant trapping efficiencies, and smoking stains reflect variations in smoking behavior. Presented herein are the results of a structured literature review that was done to identify Cigarette Filter–based assays that may serve as proxies for mouth-level exposure and assessing smoking methods. Methods: A search of the published scientific literature and internal tobacco company documents from 1954 to 2009 was carried out. Results: The literature search identified diverse schemes for assessing Cigarette Filters, including visual inspection and digital imaging of smoked-stained spent Filters, and quantitative determinations for total particulate matter (TPM), nicotine, and solanesol. The results also showed that: ( a ) there are sufficient data to link Filter-based chemical measures to standardized smoking machine–measured yields of tar and nicotine; ( b ) TPM eluted from Filters or in chemical digest of Filters can be used to estimate the efficiency of the Filter for trapping smoke solids; ( c ) visual and digital inspection of spent Filters is useful in finding indicators of variations in smoking behaviors; and ( d ) there is a correlation between solanesol and nicotine measured in Filters and exposure biomarkers in smokers. Conclusions: The Cigarette Filter may prove useful in estimating smoking behaviors such as Filter vent blocking and puffing intensity, and may have utility as proxy measures of mouth-level smoke exposure in clinical trials. Additional investigations are needed to compare the different proposed assay schemes and the assay results with measurements of human biomarker assays of smoke exposure. (Cancer Epidemiol Biomarkers Prev 2009;18(12):3321–3333)

  • Cigarette Filter-based assays as proxies for toxicant exposure and smoking behavior - A literature review
    Cancer Epidemiology Biomarkers and Prevention, 2009
    Co-Authors: John L. Pauly, Geraldine M. Paszkiewicz, K. M. Cummings, Mirjana V. Djordjevic, Richard J. O'connor, Peter G. Shields
    Abstract:

    BACKGROUND: Cigarettes are being marketed with Filters that differ in composition and design. The Filters have different toxicant trapping efficiencies, and smoking stains reflect variations in smoking behavior. Presented herein are the results of a structured literature review that was done to identify Cigarette Filter-based assays that may serve as proxies for mouth-level exposure and assessing smoking methods.\n\nMETHODS: A search of the published scientific literature and internal tobacco company documents from 1954 to 2009 was carried out.\n\nRESULTS: The literature search identified diverse schemes for assessing Cigarette Filters, including visual inspection and digital imaging of smoked-stained spent Filters, and quantitative determinations for total particulate matter (TPM), nicotine, and solanesol. The results also showed that: (a) there are sufficient data to link Filter-based chemical measures to standardized smoking machine-measured yields of tar and nicotine; (b) TPM eluted from Filters or in chemical digest of Filters can be used to estimate the efficiency of the Filter for trapping smoke solids; (c) visual and digital inspection of spent Filters is useful in finding indicators of variations in smoking behaviors; and (d) there is a correlation between solanesol and nicotine measured in Filters and exposure biomarkers in smokers.\n\nCONCLUSIONS: The Cigarette Filter may prove useful in estimating smoking behaviors such as Filter vent blocking and puffing intensity, and may have utility as proxy measures of mouth-level smoke exposure in clinical trials. Additional investigations are needed to compare the different proposed assay schemes and the assay results with measurements of human biomarker assays of smoke exposure.

  • Philip Morris clinical study of carbon Filtered Cigarettes challenged by nondisclosure issues
    Nicotine and Tobacco Research, 2009
    Co-Authors: John L. Pauly, Vaughan Rees, Richard O'connor
    Abstract:

    Scientists from Philip Morris USA recently reported a clinical study in which they claim a significant reduction in biomarkers of exposure to "gas vapor" phase smoke constituents among smokers who switched from conventional Filter Cigarettes to Cigarettes with Filters containing activated carbon (Sarkar et al., 2008). The test Cigarettes were prototypes, made in-house, and coded as TC-6 and TC-11. Each test Cigarette Filter contained a charcoal form of activated carbon from an undisclosed supplier.

  • Consumers' knowledge and beliefs about the safety of Cigarette Filters
    Tobacco Control, 2001
    Co-Authors: Janice L. Hastrup, Cummings Km, Tracy L Swedrock, Andrew Hyland, John L. Pauly
    Abstract:

    Editor,—The primary purpose of the Cigarette Filter is reduction of tar in tobacco smoke.1 2 Filters also keep tobacco flakes out of smokers' mouths.1 The standard Filter used on Cigarettes today contains 15 000 fibres per Filter.1 Several studies have demonstrated that the Filter material (cellulose acetate fibres) can become detached.3-7 Pauly and colleagues have recently observed Cigarette Filter fibres in human lung specimens, indicating that the material is respirable.8 A study of Filter fibres implanted in mice for six months demonstrated that fibres resist biodegradation.5 As a result of burning tobacco, the discharged fibres are also coated with tobacco tar, which contains carcinogens.5 Such inhaled Filter fibres may pose a previously undefined health risk to …

Ian M. Fearon - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Cigarette Filter ventilation on smokers’ mouth level exposure to tar and nicotine
    Regulatory Toxicology and Pharmacology, 2017
    Co-Authors: John W. Caraway, Christopher J. Shepperd, Madeleine Ashley, Sheri A. Bowman, Graham Errington, Krishna Prasad, Paul R. Nelson, Peter Chen, Ian M. Fearon
    Abstract:

    Cigarette Filter ventilation allows air to be drawn into the Filter, diluting the Cigarette smoke. Although machine smoking reveals that toxicant yields are reduced, it does not predict human yields. The objective of this study was to investigate the relationship between Cigarette Filter ventilation and mouth level exposure (MLE) to tar and nicotine in Cigarette smokers. We collated and reviewed data from 11 studies across 9 countries, in studies performed between 2005 and 2013 which contained data on MLE from 156 products with Filter ventilation between 0% and 87%. MLE among 7534 participants to tar and nicotine was estimated using the part-Filter analysis method from spent Filter tips. For each of the countries, MLE to tar and nicotine tended to decrease as Filter ventilation increased. Across countries, per-Cigarette MLE to tar and nicotine decreased as Filter ventilation increased from 0% to 87%. Daily MLE to tar and nicotine also decreased across the range of increasing Filter ventilation. These data suggest that on average smokers of highly ventilated Cigarettes are exposed to lower amounts of nicotine and tar per Cigarette and per day than smokers of Cigarettes with lower levels of ventilation.

You-lo Hsieh - One of the best experts on this subject based on the ideXlab platform.

  • coaxial electrospun cellulose core fluoropolymer shell fibrous membrane from recycled Cigarette Filter as separator for high performance lithium ion battery
    ACS Sustainable Chemistry & Engineering, 2015
    Co-Authors: Fenglin Huang, Yangfen Su, Yunfei Xu, Bin Peng, Feng Jiang, You-lo Hsieh
    Abstract:

    This paper reports an eco-friendly approach for extracting cellulose acetate (CA) from waste Cigarette Filter to construct a cellulose-based membrane separator for a high-performance lithium-ion battery. A cellulose/poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) nanofiber membrane was prepared by coaxial electrospinning of a cellulose acetate core and PVDF-HFP shell, then hydrolyzed by LiOH. The cellulose-core/PVD-HFP-shell fibrous membrane shows good tensile strength (34.1 MPa), high porosity (66%), excellent thermal stability (to 200 °C), and super electrolyte compatibility (355% electrolyte uptake). It has a lower interfacial resistance (98.5 Ω) and higher ionic conductivity (6.16 mS cm–1) than those of commercial separators (280.0 Ω and 0.88 mS cm–1). In addition, the rate capability (138 mAh·g–1) and cycling performance (75.4% after 100 cycles) are also superior to those of the commercial separators, demonstrating the cellulose-core fibrous membrane to be a promising separator for a high-...

  • Coaxial electrospun cellulose-core fluoropolymer-shell fibrous membrane from recycled Cigarette Filter as separator for high performance lithium-ion battery
    ACS Sustainable Chemistry and Engineering, 2015
    Co-Authors: Fenglin Huang, Yangfen Su, Yunfei Xu, You-lo Hsieh, Bin Peng, Feng Jiang, Qufu Wei
    Abstract:

    This paper reports an eco-friendly approach for extracting cellulose acetate (CA) from waste Cigarette Filter to construct a cellulose-based membrane separator for a high-performance lithium-ion battery. A cellulose/poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) nanofiber membrane was prepared by coaxial electrospinning of a cellulose acetate core and PVDF-HFP shell, then hydrolyzed by LiOH. The cellulose-core/PVD-HFP-shell fibrous membrane shows good tensile strength (34.1 MPa), high porosity (66%), excellent thermal stability (to 200 °C), and super electrolyte compatibility (355% electrolyte uptake). It has a lower interfacial resistance (98.5 Ω) and higher ionic conductivity (6.16 mS cm-1) than those of commercial separators (280.0 Ω and 0.88 mS cm-1). In addition, the rate capability (138 mAh·g-1) and cycling performance (75.4% after 100 cycles) are also superior to those of the commercial separators, demonstrating the cellulose-core fibrous membrane to be a promising separator for a high-power and more secure lithium-ion battery.