Vol. 7. 96 7-979. November 1998 Cancer Epidemiology, Biomarkers & Prevention 967
Glass Fiber Contamination of Cigarette Filters: An Additional Health Risk to the Smoker?’
John L. Pauly,2 Hans J. Lee, Edward L. Hurley, 118/120, 98%; Menthol, n 120/120, 100%). Likewise, K. Michael Cummings, Joel D. Lesses, and 99% of NEW Eclipse had glass fibers on the redesigned Richard J. Streck filter (Regular, n = 119/120). In contrast, glass fibers Department of Molecular Immunology [J. L. P., H. J. L., J. D. L., R. J. S.], were never observed on the filters of conventional United Microscopy Ultrastructure Facility [E. L. H.], Cancer Control and States filter cigarettes that had been used as controls Epidemiology [K. M. C.], Roswell Park Cancer Institute (a unit of the New (n 0/120, 0%). In a study of Eclipse (n = 60), the York State Department of Health), Buffalo, New York 14263 number of glass fibers contaminating the filter surface ranged from S to 55. Glass fibers as well as fiber fracture items [aspect ratio, <3:1 (e.g., particles, fragments, bits, Abstract chips, flakes, specks, and dust)] were discovered in the We report here the results of studies documenting the pack residue. The average number of glass fibers in the contamination of a cigarette-appearing smoking article residue of a pack of Eclipse was 7,548 (SE ± 3443; range, labeled Eclipse with glass fibers, fragments, and particles. 1,164 to 26,725 glass fibers/pack; n 7 packs). The thin Eclipse, a product of the R. J. Reynolds Tobacco and fragile glass fibers of the insulation mats had most Company (RJR), was commercialized in June of 1996. likely been broken and fragmented in the high-speed Eclipse is unlike conventional cigarettes in that, like its multiple-step Eclipse manufacturing operation. predecessor Premier, it is designed to heat and not burn Invariably, puffing on Eclipse discharged glass fibers and tobacco. The purpose of Eclipse was to simplify the glass particles from the filter into the smoker’s mouth. chemical composition and reduce the biological activity of Subsequently, the bioresistant glass fibers and the mainstream and sidestream smoke and to achieve a microscopic glass dust are inhaled and/or ingested. significant reduction of environmental tobacco smoke. In Contamination of Eclipse filters with glass fibers and Eclipse, tobacco pyrolysis is reduced by a carbon fuel rod glass dust poses a potential and unnecessary health that serves as a heat source for generating an aerosol hazard to uninformed consumers. Eclipse is a paradigm having nicotine and tobacco flavor. The carbon rod, at of the health danger that may be imposed by technically the tip of the cigarette, is insulated and bound with two complex tobacco articles and nicotine delivery devices wrapping mats of glass fibers. Recently, Eclipse has been promoted by an unregulated industry to smokers modified to address consumer complaints of burdensome worldwide, many of whom are addicted to nicotine and draw and off-taste. The redesigned Eclipse, which we who seek a less hazardous cigarette. have termed the NEW Eclipse, has an unconventional filter-appearing mouthpiece that consists of a cellulose Introduction acetate cylindrical bundle with a central hollow tunnel. In our analysis of Eclipse, glass fibers (length:width aspect In 1987, RJR3 announced Premier, and a market test was ratio, 3:1) were: (a) observed protruding from the tip; conducted from October 1988 through February 1989 (1-4). (b) identified on the white cigarette wrapping paper; (c) Premier was one of several smoking articles defined by RJR as viewed on the surface of the cork-appearing tipping “NEW CIGARETTE Prototypes That Heat Instead Of Burn paper; (d) found in the pack residue; (e) discovered lying Tobacco” (1-1 1). The stated objectives of these cigarette-ap- freely on the cut surface of the filter by both light and pealing devices, as set forth in an RJR monograph (10), were electron microscopy; (J) harvested from the filter with to: (a) simplify the chemical composition of mainstream and adhesive tape; and (g) displaced when Eclipse was sidestream smoke emitted by the “NEW CIGARETTE” (10); smoked mechanically. In a study of Eclipse that had not (b) minimize the biological activity of the mainstream and been removed from carefully opened packs, we observed sidestream smoke emitted by the NEW CIGARETTE: and (c) that 95% of the filters were contaminated with glass achieve significant reduction of environmental tobacco smoke fibers (Eclipse: Regular, n 114/120, 95%; Muds, n from the NEW CIGARETTE (see also RJR reports, Refs. 6, 12, and 13). The performance of Premier in the market evaluation was
poor (2-5, 7, 8, 1 1 ). Smokers rejected Premier because of Received 6/26/97; revised 7/20/98; accepted 7/27/98. off-taste, difficulty in lighting, and other problems (2-5, 7, 8, The costs of publication of this article were defrayed in part by the payment of 1 1), Premier was reconfigured to address these shortcomings page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. I Supported in part by NiH Grants CA-67827 and Roswell Park Cancer Institute Cancer Center Core Grant P30 CA16056. 2 To whom requests for reprints should be addressed, at Department of Immu- 3 The abbreviations used are: RJR, R. J. Reynolds Tobacco Company: SEM. nology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY scanning electron microscopy: SEM/EDX, SEM energy dispersive X-ray micro- 14263. Phone: (716) 845-8538: Fax: (716) 845-8906: E-mail: pauly@SC3102. analysis: NTP, National Toxicology Program: PAH. polycyclic aromatic hydro- med.buffalo.edu. carbon.
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(2-5, 7, 8, 1 1). After 3 years of development, Eclipse was available information, we conclude that fibrous glass materials
introduced (2-5, 7, 8, 1 1). Features of Premier and Eclipse have are carcinogenic. .. “ (17). been described in more than 20 U. S. Patents (9, 10), and patent protection has been sought in more than 1 10 countries (10). Materials and Methods In June of 1996, Eclipse began selling in Chattanooga, TN Eclipse, NEW Eclipse, and Conventional Cigarettes. (1, 3). Soon thereafter, the market test was expanded. In 1998, Eclipse from RJR was the test article of this study. The Regular, Eclipse is being sold in other United States cities. Additionally, Milds and Menthol Eclipse articles were purchased from 1996 Eclipse is being sold in different countries under various trade through 1997 from retail vendors in Chattanooga, TN. The names (Ref. 1 ; see “Materials and Methods”). In September of NEW Eclipse articles were bought from retail stores in Lincoln, 1997, RJR introduced a modified version ofEclipse to Lincoln, NE and Chattanooga, TN; these were procured in 1998. We NE ($2.69 per pack, including tax; Ref. 14). We have desig- nated the neengineered Eclipse as the NEW Eclipse. When analyzed also Eclipse that had been licensed by RJR for sale in Sweden (Inside, Regular, and Menthol; Svenska Tobaks, AB, compared with the original Eclipse, significant changes in the Stockholm, Sweden), and in Germany (HiQ, Regular; German NEW Eclipse included: (a) improved lighting; (b) filter mod- subsidiary of RJR).4 Premier smoking articles from RJR were ification; (c) more tobacco taste; and (d) 80% less secondhand provided by colleagues who had purchased them during the test smoke; the corresponding value cited by RJR for the original market period from retail dealers. Conventional United States Eclipse was 90% (14). filter cigarettes were used as controls. The conventional ciga- Eclipse has the outward appearance and geometry of a rettes were of different: (a) brands (e.g., premium and dis- conventional cigarette (Refs. 1, 3, 4, 9, and 10; Fig. 1) and is count); (b) manufacturers (e.g., RJR and other United States obtainable in four king-size styles: Regular, Milds, Menthol, tobacco companies); (c) styles (e.g., Regular, Mild, and Men- and Menthol Milds (1, 3). thol); and (‘0 packaging (e.g., hard and soft pack). All had been Opening Eclipse with a razor (Fig. I) revealed that it is a purchased from retail merchants in Erie County, NY. multiple component, technically sophisticated smoking device having many items not found in conventional cigarettes (1-5, 7, Inspection of Eclipse and Conventional Cigarettes. Packs of 9). Essential to the design of both Premier and Eclipse was the Eclipse and conventional cigarettes were opened carefully in goal that tobacco pyrolysis was to be reduced greatly (6, 10). the laboratory and by personnel familiar with the purpose and This was accomplished with the use of a carbon fuel nod (Refs. scope of our investigation. Safeguards were used to protect both 1, 3, 4, and 6-10; Figs. 1 and 2, a and b) that, when ignited, Eclipse and conventional cigarettes from airborne fiber and would heat reconstituted tobacco to generate a low-smoke particle contaminants. A partial listing of the precautions used nicotine containing aerosol that imparts a tobacco taste (1, 3, 4, are as follows: (a) after unwrapping and discarding the cello- 7, 9, 10). phane film, the flip-top lid was reflected and taped to maintain Unlike a conventional cigarette, Eclipse does not burn the pack in an open position. The front aluminum foil was lifted down to the filter when smoked; the spent Eclipse retains its off carefully and discarded. The back aluminum foil was re- length (Fig. 1; Refs. 4, 9, and 10). When smoked, Eclipse moved by cutting with clean scissors. All manipulations were displays an ash-appearing tip that consists mostly of an insu- performed without contacting or moving the Eclipse. Particular
lation mat of glass fibers (Fig. 1 ; Refs. 1 , 4, 9, and 10). Eclipse care was exercised in not touching the filter, the major test site burns very little paper, which, in conventional cigarettes, is of this study; (b) Eclipse articles were examined immediately impregnated with burn accelerators and smoke modifiers (Fig. after opening the package so as to reduce the exposure and risk 1; Refs. 10 and 15). The burning (-900#{176}C; Refs. 4 and 10) to contaminants; (c) the filters were inspected for glass fibers carbon nod is insulated with two glass fiber mats (Fig. 1 ; Refs. without removing the Eclipse or conventional cigarettes from 4, 9, and 10). The primary function of the glass mats is to: (a) the pack. After inspection of the filters for glass fiber contam- secure the position of the carbon fuel rod; (b) insulate the inants, the top was closed, and the pack was stored in a burning rod; and (c) direct the heat from the rod to the adjacent stationary upright position in a closed plastic container; (d) tobacco column (10). Other components of Eclipse have been conventional cigarettes, which had been handled in a similar described in detail elsewhere (9, 10). manner, were used as assay controls; (e) for some tests, the The Eclipse filter resembles that of a conventional ciga- Eclipse and conventional cigarettes were taken out of the pack. rette; however, the filter nod has been truncated and is approx- In these assays, examinations for glass fibers and particles were imately one-third the length (Fig. 1; Refs. 3, 9, and 15). The conducted immediately after removing the Eclipse and conven- filter rod of conventional cigarettes consists of thousands of tional cigarettes; and (f) samples for SEM or SEM/EDX were Y-shaped cellulose acetate fibers (Ref. 16; see also Ref. 15). transported and stored in closed boxes and examined immedi- Y-shapcd cellulose acetate fibers that are similar in appearance ately after removing. are used in the filters of Eclipse and NEW Eclipse. Examination of the Tip of Eclipse. The tip of Eclipse was Observations obtained in our initial inspection of Eclipse inspected to assess the integrity of the two glass fiber insulation raised concern that the thin and fragile glass fibers of the mats. For this evaluation, a pack was inverted, and the paper- insulation mats may break during manufacturing and contam- board was cut carefully from the bottom of a pack with scissors mate the surface. To address this hypothesis, a study was (Fig. 2) without contacting or disturbing the Eclipse articles. conducted to: (a) determine whether the glass fibers and par- The tip was scrutinized with a stereo-zoom microscope. After tides are present in the pack residue and the surface of Eclipse; completing the microscopic examination of the glass mats and and (b) if present, is there evidence to assume with reasonable carbon rod, the Eclipse articles were removed carefully and certainty that the glass fibers would be inhaled and/or ingested individually with forceps from the pack and positioned at when Eclipse is smoked as intended. The rationale for under- taking these studies is derived in part from animal and human studies that have for many years addressed the health risks of inhaled glass fibers; in evaluating these findings, it was con- 4 Eclipse is also marketed in Japan (AIRS); however, AIRS was not available for cluded in 1994 that: “From our comprehensive review of the our study.
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0
Fig. 1. Components of Eclipse.
Upper panel, nonsmoked Eclipse; ‘ w 5 4 middle panel, Eclipse after being completely smoked; lower panel, nonsmoked Eclipse that has been cut open to illustrate: a, carbon fuel rod; b, insulation mats of glass fibers; c, tobacco paper; d, column wrapping of white paper with an interior lam- 0 mate aluminum foil heat barrier; e, distal column of reconstituted tobac- . co; f proximal column of reconsti- tuted tobacco; g, tipping paper with a cork-like appearance; h, laser- generated holes for side-stream ven- tilation and smoke dilution (we have I enlarged the size of the holes to fa- cilitate viewing their position and number); and i, filter of cellulose acetate fibers. Eclipse length, 83 o;a mm. 0 0 0
different angles so as to permit critical microscopic viewing of processed in the same manner but which contained either: (a) the tip at different perspectives. no pack residue (i.e., microscope slide and micropore mem- Analysis of the Pack Residue for Glass Fibers and Particles. brane control); or (b) residue from packs of control cigarettes. The debris at the bottom of the pack of Eclipse and conven- For nonquantitative morphological and chemical analysis, the tional cigarettes was examined for glass fibers, particles, and residue was collected directly (e.g. , no water, no membrane, no fragments. In this investigation, the top of the pack was opened, dry ing, and no mounting) onto a glass microscope slide or SEM and all of the Eclipse articles were removed. Then, the pack was stub (see below). inverted, and the residue was tapped from the pack directly into Fibers, defined by the National Toxicology Program a cartridge that is marketed to analytical laboratories for the (United States Department of Health and Human Services), quantitative analysis of airborne fibers and particles (Zefon, were recognized as structures having a length:diameter aspect Inc., St. Petersburg, FL). We selected a standard cartridge that ratio of 3: 1 or greater ( 18). Glass structures having an aspect had been preloaded with a 25-mm diameter micropore (0.45- ratio of <3: 1 were defined as particles; the term particle is used m) membrane. The plastic disposable cartridge was clamped herein as a generic term that includes other descriptive expres- in an upright position to a vertical pole of a laboratory stand that sions including fragments, flakes, bits, chips, specks, and dust. had been placed in a laminar flow hood. Afterward, the pro- In identifying glass fibers and particles by polarized micros- tective seal was removed, and the cartridge was opened. Then, copy, we used protocols and schema used routinely for fiber the aluminum foil liner of the cigarette package was extracted identification by forensic scientists ( 19). Unlike all other fibers and flushed thoroughly with a stream of fiber-free water that and particles, glass items do not polarize light; this is defined as was directed into the cartridge. The pack residue sample that isotropic (19). This unique optical property, transparency, size had been transferred to the assay cartridge was then deposited [i.e., diameter(s)], cross-sectional shape, surface morphology, gently onto the membrane by low-vacuum filtration. During color, terminus (i.e. , end) appearance, and other optical and this step, the cartridge walls were rinsed thoroughly with a morphological characteristics were used to distinguish Eclipse- stream of hospital grade water. Thereafter, the micropore mem- derived glass fibers and glass particles from other items found brane was removed and dried at 56#{176}Cina covered plastic Petri in the pack residue. dish. Filter Tipping Paper Tested for Glass Fibers. The surface of After placing the membrane onto a clean glass slide, the the cork-appearing tipping paper of Eclipse and conventional disc was cleared, and a coverglass was mounted using Cytoseal cigarettes was tested for glass fibers. For this purpose, the filter 60 (Stevens Scientific, Riverdale, NJ). The number of glass was rolled one complete rotation on a strip of clear adhesive fibers was determined by inspecting the membrane with a tape. The tape was then adhered to a clean microscope slide, microscope that had been configured for viewing with white, and the number of glass fibers collected was enumerated with polarizing, and phase-contrast lighting as well as epifluorescent lighting with different filter configurations. The number of a microscope configured for viewing with white and polarizing light. glass fibers in each of five microscopic fields (X 10 objective) of each membrane was counted and recorded. The mean num- Filter Surface Examined with a Stereo-Zoom Microscope. ber per field and the viewing field area were then used to Packs of Eclipse and conventional cigarettes were opened, as calculate the total number of glass fibers in the residue of a described above, and the faces of the filters were inspected for pack. glass fibers with a stereo-zoom microscope (Stereomaster; Controls consisted of micropore membranes that had been Fisher Scientific). Each filter face, and portions thereof, was
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: ‘ r
A A - A -A A.
Fig. 2. Glass fibers in Eclipse. a, two packs of Eclipse. as viewed after inverting and removing the bottom wrapping paper. b, close-up view of . Eclipse, from the previous panel. Illustrated are the two mats of glass fibers that sandwich the ./ I tobacco paper (black arrow). Also shown is the carbon fuel rod that is insulated by the glass mats. Open arrow, a bundle of glass fibers dis- placed from the insulation mats. c, detailed view of the tips of two Eclipse articles that illustrates a multitude of glass fibers that form the insula- tion mats and carbon particles (arrow) displaced from the fuel rod. d, glass fibers protruding from the tips of two Eclipse that had been removed carefully from a freshly opened pack. Arrow, one of several glass fibers that were seen on the surface of the cigarette. e, view with a light microscope of the residue of a pack of Eclipse. Shown are numerous glass fibers of variable length. Also illustrated are glass fiber-derived particles, three of which have been denoted with an arrow (X50). f view with a SEM of the broken end of a glass fiber that was found in the pack residue of Eclipse. Binder is present as randomly dispersed amorphous dabs as well as a film-like substance (arrow) dripping from the glass fiber surface (bar, 1.0 sm).
scrutinized without removing the articles from the pack. Ini- precise focusing; (b) both the glass and cellulose fibers are tially, the field of observation was adjusted to permit imaging translucent. Furthermore, light was reflected from the smooth of the whole filter (15-fold magnification; X 1 .5 objective and surface of both fiber types. When compared with vertical light- x I0 ocular). For a more detailed viewing of the filter, we used ing, oblique shadow-casting illumination provided better di- the variable magnification afforded by the stereo-zoom optics. mension and enhanced the contrast of the glass and cellulose The magnification was usually within an X8 to X40 range. The acetate fibers; and (c) glass fibers and particles were seen both resolution at these magnifications was about 73 and I 35 lines! atop and within the column of large cellulose acetate fibers. mm, respectively.5 Consequently, resolving the glass at different depths within the Glass fibers upon and within the Eclipse filter were seen filter was facilitated by adjusting repetitively and simulta- using a conventional stereo-zoom microscope and standard neously both the illumination and focus. illumination. We learned, however, that better viewing of the We established the following technique whereby the filter glass fibers was achieved with duel gooseneck fiber-optic of each Eclipse in a pack could be analyzed efficiently and lamps from a 4.8-W halogen light (Dolan Jenner Industries, expediently for glass fibers with a stereo-zoom microscope. In Inc., Lawrence, MA). The lamps were placed in an opposing this method, one hand was positioned on one of the gooseneck left- and right-hand position. Each lamp was positioned at an halogen lamps to direct oblique lighting onto the cut surface of oblique angle, usually 5#{176}to15#{176}tothe horizontal. the cigarette filter, while the other hand was used simulta- The advantages afforded by this illumination scheme were neously to adjust the focus of the microscope. as follows: (a) the Eclipse and conventional cigarette filter are Filters Assayed for Glass Contaminants with a Fiber Trans. composed of numerous cellulose acetate fibers, and these fibers fer Test. We have developed a test for harvesting loose fibers are oriented longitudinally to form the cylinder-shaped filter and particles on the surface of a cigarette filter for analysis (16). plug. Microscopically, the on-end view of the filter fibers The transfer assay, as used for detecting glass fiber contami- revealed a carpet-like appearance. Inspection of glass fibers on nants of the Eclipse filter, was conducted as follows. We this morphologically complex surface at high-power required affixed to a board a 3 X 2-inch piece of clear tape (Scotch SuperClear; 3M Company, St. Paul, MN). An Eclipse or control cigarette was orientated perpendicular to the tape and posi- 5 H. Kaneko (Carton Optical Industries, Tokyo. Japan), personal communication. tioned directly above the tape. Then, the end of the filter was
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touched to the adhesive side of the tape. Immediately thereafter, a-c). In many instances, glass fibers was seen protruding from the same filter was touched a second time to an adjacent spot on the insulation rolls (Fig. 2, a and b). Glass strands projecting the tape. The tape was then pressed, sticky-side down, onto to outwardly from the mat were detectable with the naked eye and a clean, fiber-free, 3 X 2-inch glass microscope slide. The two were visible readily with a hand-held magnifying glass. Greater contact spots were then examined with a polarizing microscope, definition of the glass rods extending randomly from the cut and the glass fibers were counted and the number recorded. surface of the Eclipse tip was obtained with a stereo-zoom Filters Inspected for Glass with an Electron Microscope. microscope (Fig. 2d). The flat face of the test filter was examined for glass fibers and An assay was performed to define the relative frequency of particles with a SEM. In this analysis, a precleaned and new glass strands extending from the Eclipse tip. In this test, we razor blade was used to slice carefully a 3-4-mm transverse evaluated Eclipse (n = 60) that had been obtained from three section from the mouth end of the Eclipse filter. Particular care different Eclipse packs (A, Regular; B, Milds; and C, Menthol). was exercised not to touch the face of the filter with fingers or Each Eclipse was placed on the stage of a stereo-zoom micro- instruments so as to avoid transferring any extraneous glass scope and examined individually. The following scoring plan fibers. Using standard SEM methodologies, the test filter sec- was used to categorize the number of glass fibers that extended tion was glued in an upright position upon an aluminum SEM 1 mm or more from the tip: group I (<5 fibers/Eclipse); group stub. The filter was coated with gold (Edwards Model 360 II (5-15); and group III (> 15). Values recorded were as fol-
Evaporator; Grand Island, NY). Then the filter surface was lows: group I: pack A = 1/20 Eclipse, B = 3!20, and C viewed with an Autoscan SEM (Etec, Inc., Hayward, CA) or as 12/20; group II: A = 9/20, B = 1 l!20, and C = 5/20; and group described below. III: A 9/20, B = 3/20, and C = 1/20. Thus, 63% of the SEM/EDX Analysis of Glass Particles. Confirmation of par- Eclipse (n = 38/60) displayed five or more glass fibers that tides as glass, undoubtedly arising from Eclipse glass fibers, protruded 1 mm or more from the tip. was established using two different methods: (a) polarized Glass Fibers Observed on the Paper Wrappers of Eclipse microscopy (Ref. 19; see above); and (b) analytical scanning Articles. Glass strands were observed on the white paper electron microscopy energy dispersive X-ray microanalysis wrapper of the Eclipse articles, including the shaft and tip (Fig. (20). In the EDX analysis, we used an Hitachi 5-800 field- 2 i’). No tests were performed to define the frequency with emission SEM (Hitachi Scientific Instruments, Mountain View, which glass fibers occurred on the white paper wrapping be- CA) with an accelerating voltage of 25 kV. X-ray spectra were cause we thought that it would be more informative to analyze collected with a PGT X-ray microanalyzer probe (Princeton the mouthpiece for glass fiber contamination. Gamma-Tech, Princeton, NJ). The X-ray spectra recorded for Glass Fibers Seen on Cork-like Tipping Paper. An exami- the suspect glass particles was compared with Eclipse-derived glass fibers. We have recently used this methodology for de- nation was undertaken to learn whether glass fibers were pres- fining the elemental (chemical) composition of inhaled path- ent on the cork-like mouthpiece. Of the 16 Eclipse articles that des in human lungs (21). we examined, all tipping papers had been contaminated with glass strands. Included in this analysis were both Eclipse (n Mechanical Smoking of Eclipse. The release of glass fibers 12) and NEW Eclipse (n 4). Each Eclipse was from a from the filter of Eclipse articles was tested with a smoking different pack and had been collected randomly. The number of machine. The smoking machine was constructed at the Roswell glass fibers on the tipping paper ranged from 5 to 44 (mean ± Park Cancer Institute (Electrical Bioengineering Instrumenta- SE, 23 ± 2.4). tion Center and Occupational and Environmental Safety). The Charcoal particles, undoubtedly derived from the fuel rod, machine was engineered to permit cigarettes to be smoked with were also observed frequently on the tipping paper of Eclipse preselected smoking conditions. The machine smoking param- eters could be varied to approximate the smoking behavior of and NEW Eclipse. Also discovered on the tipping paper of smokers (6). In these studies, the machine settings were as Eclipse, NEW Eclipse, and Camel cigarettes were cellulose follows: (a) puff volume, 35 cc; (b) puff duration, 2.0 s; (c) puff acetate particles and broken fibers. vacuum, 10 mm H20; (d) puff frequency, one every 60 s; and In contrast, no glass fibers or charcoal particles were (e) total puffs per Eclipse, -10. observed on the tipping papers of conventional filter cigarettes The glass fiber release assay was performed in the follow- (Camel, RJR; n = 4). Likewise, no glass fibers were observed ing manner. The filter surface of an Eclipse was examined with on the negative control slides (n = 4). a stereo-zoom microscope. X- and Y-coordinates were estab- Glass Fibers Found in Eclipse Pack Residue. Having ob- lished by positioning four small marks with a black felt tip pen served glass fibers protruding from the tip of Eclipse articles on the filter tipping paper. Then, for each filter surface, a map and present on both the white wrapping paper and cork-appear- was drawn of the location and orientation of glass fibers that ing tipping paper, we undertook a study to learn whether glass were observed with a stereo-zoom microscope. Thereafter, the fibers were present in pack residue of Eclipse. For all Eclipse Eclipse was positioned onto the smoking machine, ignited with packs examined, numerous glass fibers were present in the pack a butane cigarette lighter, and smoked mechanically. After residue (Fig. 2e). The glass fibers were differentiated effort- smoking, the filter surface was reexamined and compared with lessly from the few other fiber types that were found in the the original map. The displacement of one or more glass fibers residue and which included paper strands and cellulose acetate was recorded as a positive test. filter fibers. Glass fibers in the pack residue, however, were indistinguishable from the glass fibers of the mats at the tip of Results the Eclipse. Displaced and Protruding Glass Fibers Observed on Eclipse Glass material in the pack was morphologically heteroge- Article Tip. The two insulation mats of glass fibers on the tip neous. Fibers were always observed and were of variable of Eclipse are shown in Figs. 1 and 2. An on-end inspection of length. Remarkably long glass fibers (>200 m) as well as the tip revealed marked variation in the integrity of the glass short fibers were observed in all packs. Glass that was recog- mats; frequently, clusters of glass fibers were displaced (Fig. 2, nized as components of the shattered glass fibers were present
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Glass Fibers Seen On Eclipse Filter