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Miller-Holt J, Behrsing H, Crooks I, Curren R, Demir K, Gafner J, Gillman G, Hollings M, Leverette R, Oldham M, Simms L, Stankowski LF, Thorne D, Wieczorek R, Moore MM. Key challenges for in vitro testing of tobacco products for regulatory applications: Recommendations for dosimetry. Drug Test Anal 2023; 15:1175-1188. [PMID: 35830202 PMCID: PMC9897201 DOI: 10.1002/dta.3344] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/02/2022] [Accepted: 07/05/2022] [Indexed: 02/05/2023]
Abstract
The Institute for In Vitro Sciences (IIVS) is sponsoring a series of workshops to develop recommendations for optimal scientific and technical approaches for conducting in vitro assays to assess potential toxicity within and across tobacco and various next-generation products (NGPs) including heated tobacco products (HTPs) and electronic nicotine delivery systems (ENDSs). This publication was developed by a working group of the workshop members in conjunction with the sixth workshop in that series entitled "Dosimetry for conducting in vitro evaluations" and focuses on aerosol dosimetry for aerosol exposure to combustible cigarettes, HTP, and ENDS aerosolized tobacco products and summarizes the key challenges as well as documenting areas for future research.
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Affiliation(s)
| | - Holger Behrsing
- Institute for In Vitro Sciences, Gaithersburg, Maryland, USA
| | - Ian Crooks
- Consumer Product Safety, British American Tobacco, Southampton, UK
| | - Rodger Curren
- Institute for In Vitro Sciences, Gaithersburg, Maryland, USA
| | - Kubilay Demir
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Jeremie Gafner
- Scientific & Regulatory Affairs, JT International SA, Geneva, Switzerland
| | - Gene Gillman
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Michael Hollings
- Genetic Toxicology, Labcorp Early Development Laboratories Ltd., Harrogate, UK
| | - Robert Leverette
- Scientific & Regulatory Affairs, RAI Services Company, Winston-Salem, North Carolina, USA
| | - Michael Oldham
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Liam Simms
- Group Science and Regulatory Affairs, Imperial Brands, Bristol, UK
| | - Leon F. Stankowski
- Genetic and In Vitro Toxicology, Charles River Laboratories–Skokie, Skokie, Illinois, USA
| | - David Thorne
- Consumer Product Safety, British American Tobacco, Southampton, UK
| | - Roman Wieczorek
- Group Science and Regulatory Affairs, Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Hamburg, Germany
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Ge S, Chen Q, Zhang Z, She S, Xu B, Liu F, Afsar NU. A Comprehensive Analysis of Inorganic Ions and Their Selective Removal from the Reconstituted Tobacco Extract Using Electrodialysis. MEMBRANES 2022; 12:membranes12060597. [PMID: 35736304 PMCID: PMC9228951 DOI: 10.3390/membranes12060597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 12/07/2022]
Abstract
Many tobacco stalks, dust, and fines are discharged in the tobacco industry, rich in inorganic minerals ions and nicotine salts. The high salinity and nicotine salts are challenging to be addressed by traditional treatment and are a severe threat that ought to be overcome. Thus, proper techniques can regenerate the tobacco stalks into reconstituted tobacco flakes used as cigarette filler. The electrodialysis process has been a viable approach to removing the inorganic ingredients in wastewater. We studied concentration, pH, and co-related influences with the nicotine and sugar/nicotine contents on the desalination performance. The results show that the inorganic ions such as Cl-, K+, Ca2+, and Mg2+ ions were successfully removed. When the feed concentration ranges from 3 to 15%, the removal ratio of the K+ ions is higher than Ca2+ and Mg2+ ions. As we reported previously, the K+ and Ca2+ ions are unfavorable for the total particulate matter emission but beneficial to decreasing the HCN delivery in mainstream cigarette smoke. Selective ED is a robust technology to reduce the harmful component delivery in cigarette smoke.
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Affiliation(s)
- Shaolin Ge
- IAT USTC-AHZY Joint Laboratory of Chemistry & Combustion, Institute of Advanced Technology, University of Science and Technology of China, Hefei 230088, China;
- Anhui Key Laboratory of Tobacco Chemistry, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China; (Z.Z.); (B.X.); (F.L.)
| | - Qian Chen
- Applied Engineering Technology Research Center for Functional Membranes, Institute of Advanced Technology, University of Science and Technology of China, Hefei 230088, China;
| | - Zhao Zhang
- Anhui Key Laboratory of Tobacco Chemistry, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China; (Z.Z.); (B.X.); (F.L.)
- Key Laboratory of Combustion & Pyrolysis Study of CNTC, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China;
| | - Shike She
- Key Laboratory of Combustion & Pyrolysis Study of CNTC, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China;
| | - Bingxia Xu
- Anhui Key Laboratory of Tobacco Chemistry, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China; (Z.Z.); (B.X.); (F.L.)
| | - Fei Liu
- Anhui Key Laboratory of Tobacco Chemistry, Anhui Tobacco Industrial Co., Ltd., 9 Tianda Road, Hefei 230088, China; (Z.Z.); (B.X.); (F.L.)
| | - Noor Ul Afsar
- Anhui Provincial Engineering Laboratory of Functional Membrane Materials and Technology, Department of Applied Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
- Correspondence:
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Electrodialytic Desalination of Tobacco Sheet Extract: Membrane Fouling Mechanism and Mitigation Strategies. MEMBRANES 2020; 10:membranes10090245. [PMID: 32967125 PMCID: PMC7559822 DOI: 10.3390/membranes10090245] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/16/2022]
Abstract
In the papermaking industry (reconstituted tobacco), a large number of tobacco stems, dust, and fines are discharged in the wastewater. This high salinity wastewater rich in ionic constituents and nicotine is difficult to be degraded by conventional biological treatment and is a serious threat that needs to be overcome. Electrodialysis (ED) has proved a feasible technique to remove the inorganic components in the papermaking wastewater. However, the fouling in ion exchange membranes causes deterioration of membranes, which causes a decrease in the flux and an increase in the electrical resistance of the membranes. In this study, the fouling potential of the membranes was analyzed by comparing the properties of the pristine and fouled ion exchange membranes. The physical and chemical properties of the ion exchange membranes were investigated in terms of electrical resistance, water content, and ion exchange capacity, as well as studied by infrared spectroscopy (IR) spectra, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses. The results indicated that the membrane fouling is caused by two different mechanisms. For the anion exchange membranes, the fouling is mainly caused by the charged organic anions. For the cation exchange membrane, the fouling is caused by minerals such as Ca2+ and Mg2+. These metal ions reacted with OH− ions generated by water dissociation and precipitated on the membrane surface. The chemical cleaning with alkaline and acid could mitigate the fouling potential of the ion exchange membranes.
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Dalrymple A, Ordoñez P, Thorne D, Dillon D, Meredith C. An improved method for the isolation of rat alveolar type II lung cells: Use in the Comet assay to determine DNA damage induced by cigarette smoke. Regul Toxicol Pharmacol 2015; 72:141-9. [PMID: 25846365 DOI: 10.1016/j.yrtph.2015.03.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/26/2015] [Accepted: 03/30/2015] [Indexed: 11/28/2022]
Abstract
Smoking is a cause of serious diseases, including lung cancer, emphysema, chronic bronchitis and heart disease. DNA damage is thought to be one of the mechanisms by which cigarette smoke (CS) initiates disease in the lung. Indeed, CS induced DNA damage can be measured in vitro and in vivo. The potential of the Comet assay to measure DNA damage in isolated rat lung alveolar type II epithelial cells (AEC II) was explored as a means to include a genotoxicity end-point in rodent sub-chronic inhalation studies. In this study, published AEC II isolation methods were improved to yield viable cells suitable for use in the Comet assay. The improved method reduced the level of basal DNA damage and DNA repair in isolated AEC II. CS induced DNA damage could also be quantified in isolated cells following a single or 5 days CS exposure. In conclusion, the Comet assay has the potential to determine CS or other aerosol induced DNA damage in AEC II isolated from rodents used in sub-chronic inhalation studies.
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Affiliation(s)
- Annette Dalrymple
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK.
| | - Patricia Ordoñez
- Vivotecnia Research S.L., Parque Científico de Madrid, C/Santiago Grisolía, 2 (PTM), 28760 Tres Cantos, Madrid, Spain
| | - David Thorne
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Debbie Dillon
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Clive Meredith
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
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Ma X, Gao Y, Huang H. Treatment of papermaking tobacco sheet wastewater by electrocoagulation combined with electrochemical oxidation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 71:1165-72. [PMID: 25909726 DOI: 10.2166/wst.2015.057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Attempts were made in this study to examine the efficiency of electrocoagulation (EC) using aluminum (Al) anode and stainless steel net cathode combined with electrochemical oxidation with a β-PbO₂anode or a mixed metal oxide (MMO) anode for treatment of papermaking tobacco sheet wastewater, which has the characteristics of high content of suspended solids (SS), intensive color, and low biodegradability. The wastewater was first subjected to the EC process under 40 mA/cm² of current density, 2.5 g/L of NaCl, and maintaining the original pH of wastewater. After 6 minutes of EC process, the effluent was further treated by electrochemical oxidation. The results revealed that the removal of SS during the EC process was very beneficial to mass transfer of organics during electrochemical oxidation. After the combined process, 83.9% and 82.8% of chemical oxygen demand (COD) removal could be achieved on the β-PbO₂and MMO anodes, respectively. The main components of the final effluent were biodegradable organic acids, such as acetic acid, propionic acid, butyric acid, valeric acid, and hexahyl carbonic acid; the 5-day biochemical oxygen demand/chemical oxygen demand (BOD₅/COD) ratio increased from 0.06 to 0.85 (Al + β-PbO₂) or 0.80 (Al + MMO). Therefore, this integrated process is a promising alternative for pretreatment of papermaking tobacco sheet wastewater prior to biological treatment.
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Affiliation(s)
- Xiangjuan Ma
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, China E-mail:
| | - Yang Gao
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, China E-mail: ; School of Environment, Tsinghua University, Beijing 100084, China
| | - Hanping Huang
- Department of Production and Management, Hangzhou Liqun Environment-protecting Paper Co., Ltd, Hangzhou 310018, China
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Roemer E, Dempsey R, Hirter J, Deger Evans A, Weber S, Ode A, Wittke S, Schorp M. Toxicological assessment of kretek cigarettes Part 6: The impact of ingredients added to kretek cigarettes on smoke chemistry and in vitro toxicity. Regul Toxicol Pharmacol 2014; 70 Suppl 1:S66-80. [DOI: 10.1016/j.yrtph.2014.11.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/28/2014] [Accepted: 11/29/2014] [Indexed: 10/24/2022]
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Coggins CRE, Merski JA, Oldham MJ. A comprehensive evaluation of the toxicology of the "Deli" cast sheet process used in experimental cigarettes. Inhal Toxicol 2013; 25 Suppl 2:64-8. [PMID: 24341848 DOI: 10.3109/08958378.2013.854435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT Manufacture of cigarettes results in tobacco by-products, some of which can be processed and added back to cigarettes. Such additions (known as reconstituted tobacco or reconstituted leaf) have been shown to reduce tar yields. A new process (termed "Deli" cast sheet) is a potential refinement of the reconstitution process. OBJECTIVE Compare toxicity of smoke from experimental cigarettes made with reconstituted leaf with that from cigarettes made with Deli cast sheet. MATERIALS AND METHODS Analytical chemistry, Salmonella mutagenicity and cytotoxicity assays were used to evaluate the composition biological activity of mainstream smoke from experimental cigarettes made with Deli cast sheet or with reconstituted leaf. The effect of different amounts of guar and propylene glycol in Deli cast sheet was also evaluated. RESULTS Small increases in the amount of nitrogen oxides were found as a result of inclusion of the Deli cast sheet when compared with reconstituted leaf; no differences in cytotoxicity or mutagenicity were found. CONCLUSION The Deli process neither significantly modified chemical composition of smoke nor affected its biological activity, as measured by the mutagenicity and cytotoxicity assays used here.
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Haussmann HJ. Use of hazard indices for a theoretical evaluation of cigarette smoke composition. Chem Res Toxicol 2012; 25:794-810. [PMID: 22352345 DOI: 10.1021/tx200536w] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The chemical composition of cigarette mainstream smoke (MS) has been quantitatively analyzed in multiple studies, often with the objective to toxicologically evaluate and compare various types of MS. Increases and decreases in yields of constituents between MS types can only be consolidated if these yields are compared on the basis of toxicological properties of the individual constituents. For the risk assessment of various complex mixtures including MS, a hazard index (HI) approach has been used that requires weighing of the exposure to individual MS constituents by cancer and noncancer potency values. The objective of the current study is to review the past uses of the HI concept for MS and smokeless tobacco and discuss strengths and limitations of using this concept. Published information as well as information made available on the Web was used. The HI concept has been applied to MS for determining and comparing theoretical lifetime risks, for consumer communication, for the prioritization of constituents for reduction, for ingredient assessment, and for the selection of constituents for regulation. The limitations of this approach are associated with the limited number of MS constituents with available yield data, the gaps and uncertainties in available potency values, the application to relatively high exposure concentrations, and the default assumption of additivity. The derived theoretical noncancer index is dominated by acrolein to an extent that there seems to be not much advantage in using the HI concept for noncancer assessments. The derived theoretical cancer index is dominated by genotoxic carcinogens of the MS vapor phase and may thus complement currently used toxicological assays in a tiered evaluation approach. As is the case for every other assay and interpretation model, the HI concept needs to be applied with its limitations and weaknesses in mind. Its best application is for comparative purposes. It should be kept in mind that the HI concept is a theoretical concept and does not provide actual risk information.
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Gaworski CL, Wagner KA, Morton MJ, Oldham MJ. Insights from a multi-year program designed to test the impact of ingredients on mainstream cigarette smoke toxicity. Inhal Toxicol 2011; 23 Suppl 1:172-83. [PMID: 21545299 DOI: 10.3109/08958378.2010.546440] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT Cigarette tobacco ingredients may alter the distribution of chemical constituents present in smoke. When considering the toxicological relevance of potential ingredient-related effects on chemical and biological measurements assessing cigarette smoke toxicity, it is critical to understand the intrinsic variability of tobacco and cigarette smoke that is influenced by the environmental conditions during growing, agricultural practices during preparation, cigarette manufacturing tolerances, and stability of the assay methods. OBJECTIVE To understand possible effects of ingredients on cigarette smoke toxicity, various chemical and biological endpoints were measured in smoke from experimental cigarettes (added ingredient) to the intrinsic variability of control cigarettes (no added ingredient). MATERIALS AND METHODS Data were collected during a multi-year program testing a variety of cigarette ingredients from several chemical classes. Chemical analysis of mainstream cigarette smoke,and biological procedures (Salmonella mutagenicity, cytotoxicity, and smoke inhalation) were performed using validated and controlled laboratory methods. The within-study and temporal variation of control cigarettes manufactured in parallel with experimental cigarettes was calculated and used to measure intrinsic variability. RESULTS The overwhelming majority of data generated from experimental cigarettes fell within the experiment variability represented by the pooled standard error of the entire multi-year dataset for the control cigarettes. CONCLUSION The results of this evaluation add to a growing body of the literature regarding a weight of evidence assessment of cigarette ingredient toxicity. When assessed against the variability of assay methodology, natural agricultural change, and manufacturing control, the ingredients studied here demonstrated little relevant influence on the mainstream cigarette smoke toxicity endpoints measured.
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Johnson MD, Schilz J, Djordjevic MV, Rice JR, Shields PG. Evaluation of in vitro assays for assessing the toxicity of cigarette smoke and smokeless tobacco. Cancer Epidemiol Biomarkers Prev 2009; 18:3263-304. [PMID: 19959677 PMCID: PMC2789344 DOI: 10.1158/1055-9965.epi-09-0965] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND In vitro toxicology studies of tobacco and tobacco smoke have been used to understand why tobacco use causes cancer and to assess the toxicologic impact of tobacco product design changes. The need for toxicology studies has been heightened given the Food and Drug Administration's newly granted authority over tobacco products for mandating tobacco product performance standards and evaluate manufacturers' health claims about modified tobacco products. The goal of this review is to critically evaluate in vitro toxicology methods related to cancer for assessing tobacco products and to identify related research gaps. METHODS PubMed database searches were used to identify tobacco-related in vitro toxicology studies published since 1980. Articles published before 1980 with high relevance also were identified. The data were compiled to examine (a) the goals of the study, (b) the methods for collecting test substances, (c) experimental designs, (d) toxicologic end points, and (e) relevance to cancer risk. RESULTS A variety of in vitro assays are available to assess tobacco smoke that address different modes of action, mostly using non-human cell models. However, smokeless tobacco products perform poorly in these assays. Although reliable as a screening tool for qualitative assessments, the available in vitro assays have been poorly validated for quantitative comparisons of different tobacco products. Assay batteries have not been developed, although they exist for nontobacco assessments. Extrapolating data from in vitro studies to human risks remains hypothetical. CONCLUSIONS In vitro toxicology methods are useful for screening toxicity, but better methods are needed for today's context of regulation and evaluation of health claims.
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Affiliation(s)
- Michael D Johnson
- Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057-1465, USA
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