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SMOKING MACHINE PARAMETERS FOR COLLECTION OF TOTAL PARTICULATE MATTER AND GASES FROM LOW IGNITION- POTENTIAL CIGARETTES Harold C. Pillsbury, Jr. 13009 Magellan Ave. Rockville, MD 20853 Under contract to the U.S. Consumer Product Safety Commission #CPSC-S-92-5472 I i March 14, 1993 I 1 I I J I

page 1 I I Introduction The official Federal Trade Commission method (FTC, 1969, 1979, 1980) to determine tar, nicotine, and carbon monoxide in cigarette smoke is presented as a basis for the method of collecting total particulate matter and gases from low-ignition potential cigarettes. The FTC method is very similar to the Centre de Cooperation pour les Recherches Scientifiques au Tabac (CORESTA) Standard Method (CORESTA, 1968) used in Europe. One of these two methods or a slight modification thereof is used in all countries that test cigarettes. Differences between the FTC and the CORESTA methods are small. The environmental rooms under the CORESTA method are maintained at 22 ±3 °C and 55-65% relative humidity. The FTC method requires conditions of 75 ±2 °F (23.9 ±1.1 °C) and relative humidity of 60,±2$. Under the FTC method, cigarettes are smoked to a butt length of 23 mm or the overwrap plus 3 mm, whichever is longer. Using the CORESTA method, cigarettes with a filter length exceeding 15 mm are smoked to the length of filter plus 8 mm and cigarettes with extra long filter tips are smoked to the length of the tipping plus 3 mm. The Filtrona-400: smoking machine used in the CORESTA method requires an increased draft over the burning cigarette, whereas the FTC method does not. The increased draft is not encountered under normal smoking conditions. It causes the cigarette to burn faster, reducing the number of puffs and lowering the yield of total particulate matter (TPM) and gases. This air flow over the cigarette is needed to match the results of the Filtrona smoking machine to that of the Borgwaldt smoking machine. The Filtrona and Borgwaldt are the only two existing commercial manufacturers of smoking machines. The following is a summary of the FTC protocol. 1 I I I I I Materials and Methods 1) Environmental Room: A room where cigarette conditioning and smoking is conducted. The room should be maintained at 75 ±2 °F (23.9 ±1.1 °C) and 60% ±2% relative humidity. 2) Smoking Machine: The cigarette smoking machine should be similar to the Filtrona machine used by FTC (Pillsbury, 1969). This machine can smoke 20 cigarettes at one time, one in each port. Each port can be fitted with a filter holder and filter pad for the collection of TPM. Gases pass through the pad and are collected in specially designed plastic bags (Filtrona). I

page 2 3) Smoke Collection Trap: The polyacrylic plastic holders (Wartman, 1959) can be obtained from the manufacturer of the smoking machine (Filtrona). 4) Filter Disks: Filter disks (pads) are made from a fiberglass sheet pre-cut to a diameter of approximately 44 mm. The filters collect at least 99.9% of all particles larger than 0.3 um in diameter (Ogg, 1964). The filter disks fit into plastic holders. The particles collected on the pad are referred to as total particulate matter (TPM). 5) Standard solutions: A) Extraction solution: This solution contains extractant and internal standards- 2-propanol containing 1 mg anethole (p-propenylanisole, 1-methoxy-4-propenylbenzene) per mL as an internal standard for nicotine and 20 mg ethanol per mL as an.internal standard for water. B) Moisture content: Standards are prepared by adding measured amounts of water into measured volumes of extraction solution. A standard curve is constructed from the ratio of peak heights of the water to the peak height of ethanol against the amount of water added to the extraction solution, after correcting with a solvent blank. C) Nicotine: A stock solution contains 2.500 g nicotine in 100 mL of extraction solution. Working solutions are made from 1, 2, 3, 4, and 5 mL of the stock solution diluted and brought to 100 mL volume with extraction solution. A standard curve is constructed as with moisture content. 6) Carbon monoxide: Gases from the plastic bags in the smoking machine are passed into an infrared detector. The detector is calibrated using a carbon monoxide gas standard. 7) Gas chromatograph: A) Moisture content analysis: The 6 ft x-1/8„ (1.8 m x 0.32 cm) diameter column is packed with 80-100 mesh porous polymer (Porapak Q). Operating temperature for the column is set at 200 °C, injection port at 240 °C, and thermal conductivity detector at 210 °C. The helium carrier gas flow is about 100 mL per minute. B) Nicotine analysis: The 6 ft x 1/8" (1.8 m x 0.32 cm) diameter column is packed with 2% KOH and 10$ polyethylene glycol (Carbowax 20M) on 45-60 mesh acid washed diatomaceous earth. The column temperature is set at 165 °C, and the injection port and the flame ionization detector are set at 200-250 °C. Helium carrier gas flow is about 40 mL per minute. /+

I page 3 i i i I j I I j I I I I ! 8) "Monitor" cigarettes: These are cigarettes with known tar, nicotine and carbon monoxide yields. Monitor cigarettes serve as "standards" to ensure that the smoking machine is operating properly. True standard reference cigarettes are mentioned in Dr. Gairola's chapter on Short-term Toxicity Tests. No fewer than four ports should be used for monitors per 20 port machine on each run. 9) Run: This is a complete smoking of 100 cigarettes- five of the same type in each of the 20 ports (4 monitor and 16 test cigarettes). Samples Cigarette quantities: A minimum of 150 cigarettes and preferably 200 cigarettes of each type are needed for the FTC specified tests. This would ensure that at least 100 cigarettes of each type were succesfully smoked for one run. Typically, some test pads are discarded due to cigarette lighting failures, port leaks, or other technical problems. Sample preparation and selection: Store all cigarette samples and monitors in an environmental room or chamber for not less than 24 hours before marking or smoking. Cigarettes should remain in the environmental room until they are smoked. Select only cigarettes without physical damage. Cigarettes should be marked to either a butt length of 23 mm or the overwrap plus 3 mm, whichever is longer. The insertion depth of about 9 mm is also marked. Mark the perforations for easy identification by the technician during placement into the holder. The perforations must not be occluded or compressed by the holder since this would affect the smoke yield. Machine Smoking of Cigarettes 1) Puff volume: 35 mL # 0.5 mL 2) Puff duration: 2 sec ± 0.2 sec, measured under actual machine smoking conditions. Resulting draw velocity is about 17.5 mL per sec. 3) Puff frequency: One puff per 60 sec ± 1 sec. Weigh the filter assembly to the nearest 0.05 mg and connect it to the smoking machine so that the cigarette and filter assembly are held horizontally. Test the smoking apparatus and filter assembly for leaks. Insert a cigarette through the hole in the rubber membrane until the butt end is inserted approximately 9 mm, such that the butt end does not contact the filter disk. Light the cigarette at the beginning of the first

page 4 puff. Smoke five cigarettes per pad. If the cigarettes are very low in tar, more cigarettes may be smoked per pad providing the pad does not wet through. The cigarettes should be protected from drafts, other than normal convection, during smoking. Results After five or more cigarettes are smoked in each port, each pad is extracted with the extraction solution. The extracted material is analyzed for moisture content and nicotine levels. Other extracted materials, such as described in the Analyses chapter, may also be analyzed. Part of the gas phase, which has been accumulated in the bag, is passed through an infrared detector for the determination of carbon monoxide. Although not required by.FTC, nitric oxide may be measured by a chemiluminescent detector designed by Filtrona, specifically for the smoking machine. The gas may also be analyzed for substances indicated in Dr. Hoffman's Analysis chapter. Tar, nicotine and carbon monoxide are reported as mg per cigarette. TPM (total particulate matter): Immediately after smoking the cigarettes disconnect the filter assembly from the smoking machine. Record the weight gain of the filter assembly to the nearest 0.05 mg and divide this by the number of cigarettes smoked to determine TPM per cigarette. Extraction: Immediately after weighing, place the filter pad in a dry, rubber-stoppered 25 mL flask. Wipe out the filter assembly with one-fourth of an unused pad and place this into the flask. Add 10.0 mL of extraction solution and shake for 30 minutes. Water: A 1-10 uL aliquot of the extract is withdrawn through the stopper and injected into the chromatograph. Compare the resulting peak against the standard curve to determine the moisture content. Nicotine: A 1-10 uL aliquot of the extract is withdrawn through the stopper and injected into the chromatograph. Compare the resulting peak against the standard curve to determine the nicotine content. Carbon Monoxide: The gaseous phase collected in the plastic bag is passed through an infrared detector for the determination of carbon monoxide. Tar: Tar is the TPM minus the water and nicotine. This is sometimes referred to as "FTC tar" to distinguish it from other definitions of "tar".

page 5 Discussion 1 I I i I I i i The Filtrona smoking machine can be modified by installing a collection funnel at each port to collect sidestream smoke, which may have different constituent levels (Johnson, 1973; see also discussion in Dr. Harris' Overview chapter). Filtrona'a 8-port smoking machine is more easily modified than the 20-port model. The filter assembly can be replaced with a cold trap if this technique for collecting condensate is desired. There may be a wide range of variability in smoking behaviors due to cigarette design, physiological, psychological, and pharmacological factors (see Dr. Burns' Topography chapter; Guyatt, 1989a,b; Kolonen, 1991, 1992; Nil, 1989; Zacny, 1988). Although the present testing methods are designed to produce comparative.results, the smoking machine could be set up as closely as technically feasible to reflect future data on smoking behavior. The machine has sufficient range to acommodate possible changes, for example, puff frequency from one puff per minute to six puffs per minute or volume from 20 mL to 50 mL puffs. The draw velocity would also change since it is related to the frequency and volume. A high degree of replicability for tar, nicotine, and carbon monoxide was found in parallel testing between FTC and most other laboratories over a period of 20 years. Unfortunately, all the data from these tests were destroyed when FTC closed the laboratory in 1987. Attached to this chapter is a typical graph from my files that illustrates the close correlation of tar levels found by the FTC and a private laboratory. Cost i i The approximate cost of machine smoking and analyses for tar, nicotine, and carbon monoxide for one run with a 20-port machine would be $3,000-$4,000 (4 monitor ports + 16 test ports = 20: monitor cigarettes + 80 test cigarettes, minimum). The current capacity of the Tobacco Institute Laboratory is six runs per day. Recommendations ~ The FTC method should be used as the basis for the smoking machine setup in the collection of gases and total particulate N _ matter for low ignition-potential cigarette testing. The 0 ~ apparatus and methodology is adaptable to changes that may be N indicated by new and future data on human smoking behavior and r smoke exposure. The FTC method is replicable and well- ~ ~ established among the US industry. N . ~ J

page 6 References CORESTA Standard Method No.10 (Sept. 1968) Federal Trade Commission, Federal Register Vol.45 No.134 pp 46483-46487 (Thursday July 10, 1980) Federal Trade Commission, Federal Register Vol.44 No.13 pp 3777 (Thursday Jan. 18, 1979) Federal Trade Commission, J. Assoc. Official Analytical Chemist, Vol. 52, No. 3 1969 Guyatt, Andrew R.; Kirkhan, Andrew J.T.; Baldry, Andrew G.; Dixon, Michpl and Cumming, Gordon "How Does Puffing Behavior Alter During the Smoking of a Single Cigarette?" Pharmacology Biochemistry and Behavior Vol. 33 pp 189-195 (1989a) Guyatt, A. R.; Kirkham,A. J. T.; Mariner, D. C.; Baldy, A. G. and Cumming, Low Tar G. and "Long-Term Effects of Switching to Cigarettes Nicotine Yield" Psychopharmacology (Berlin) 99 With pp 80- 86 (1989b) Johnson, W. R.; Hale, R. W.; Nedlock,J. W.; Geubbs, H. J.and Powell, D. H. "The Distribution of Products Between Mainstream and Sidestream Smoke" Tobacco Science Vol. 17 pp 141 (1973) Kolonen, Sakar; Tuomisto, Jouko; Puustinen, Pekka and Airaksinen, Mauno M.. "Smoking Behavior in Low-Yield Cigarette Smokers and Switchers in Natural Environment" Pharmacology Biochemistry and Behavior Vol. 40 pp 170-180 (1991) Kolonen, Sakar; Tuomisto, Jouko; Puustinen, Pekka and Airaksinen, Mauno M. "Puffing Behavior During the Smoking of a Single Cigarette in a Naturalistic-Environment" Pharmacology Biochemistry and Behavior Vol. 41, pp 701-706 (1992) Nil, Rico and Battig, Karl "Separate Effects of Cigarette Smoke Yield and Smoke Taste on Smoking Behavior" Psychopharmacology Vol. 99 pp 54-59 (1989) Ogg,C.L., J. Assoc. Official Analytical Chemist 47, pp 365-362 (1964) Pillsbury, H.C., Bright, C.C., O'Connor, K.J. and Irish, F.W. J. Assoc. Official Analytical Chemist 52, pp 458-462 (1969) Wartman, et al, Analytical Chemistry 31 pp 1705-1709 (1959)

page 7 I I I I I i j i I I I Wegner, John R. and Thaggard, Neil A. "Gas-Liquid Chromatographic Determination of Nicotine Contained on Cambridge Filter Pads: Collaborative Study" Vol. 62 No. 2 (1979) Zacny, James P.and Stitzer, Maxine L. "Cigarette Brand-Switching: Effect on Smoke Exposure and Smoking Behavior" J. Pharmacology and Experimental Therapeutics Vol. 246 No. 2 pp 619-627 (1988) I

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