Title of Invention	ACTIVATED CHARCOAL FILTER FOR REDUCING P-BENZOSEMIQUINONE FROM THE MAINSTREAM CIGARETTE SMOKE
Abstract	This invention relates to a filter for a tobacco smoke inhaling/generating/producing device, comprising stipulated amounts of specific grain sizes or combination of grain sizes of activated charcoal for effectively reducing from the mainstream smoke the level of p-benzosemiquinone (p-BSQ), a relatively stable highly reactive major harmful oxidant, without significantly affecting the flavor and taste of the smoke while providing comfortable mouthful of smoke and nicotine delivery, so that the said charcoal filter cigarettes becomes potentially less hazardous safer cigarettes and may be acceptable to the smokers with marked reduction in health risk; the said charcoal filters also effectively reduce the level of nitric oxide and tar from the mainstream smoke.

Title of Invention

ACTIVATED CHARCOAL FILTER FOR REDUCING P-BENZOSEMIQUINONE FROM THE MAINSTREAM CIGARETTE SMOKE

Abstract

This invention relates to a filter for a tobacco smoke inhaling/generating/producing device, comprising stipulated amounts of specific grain sizes or combination of grain sizes of activated charcoal for effectively reducing from the mainstream smoke the level of p-benzosemiquinone (p-BSQ), a relatively stable highly reactive major harmful oxidant, without significantly affecting the flavor and taste of the smoke while providing comfortable mouthful of smoke and nicotine delivery, so that the said charcoal filter cigarettes becomes potentially less hazardous safer cigarettes and may be acceptable to the smokers with marked reduction in health risk; the said charcoal filters also effectively reduce the level of nitric oxide and tar from the mainstream smoke.

Full Text	A FILTER FOR A TOBACCO SMOKE INHALING/GENERATING/PRODUCING DEVICE Filed of the invention The present invention relates to an activated charcoal based tobacco smoke filter device, for effectively reducing level of p-benzosemiquinone (p-BSQ) a highly reactive major harmful oxidant from the mainstream cigarette smoke while providing comfortable mouthful of smoke and nicotine delivery with considerable reduction in health risk-to the smokers. The said device also reduces other components of the tobacco smoke such as nitric oxide, nicotine etc. Background and prior art references Cigarette smoking is the world's single most preventable cause of disease and death. Worldwide, about 36 percent of all adults smoke cigarettes. According to a 1999 World Health Organization estimate, there are 4 million deaths a year from tobacco. Tobacco smoke contains more than 4000 compounds. Among these, nicotine is the habit forming pharmacological agent. Others are toxins, mutagens and carcinogens that cause or enhance various degenerative diseases including cancer of lung and other organs, chronic obstructive pulmonary disease such as bronchitis and emphysema as well as heart disease and stroke. Since approaches to cessation of smoking by public health campaigns and anti-smoking laws passed by local Governments have had limited success, the most practicable approach is the prevention of the hazardous effects caused by cigarette smoke. Modification of the cigarette is in itself a practical approach to reducing the toxic compounds contained in cigarette smoke. One of the approaches was to use cigarette filters. This is what the cigarette manufacturers have been trying to do for the last few decades. The cigarette companies have introduced cigarettes with filter tips to reduce the harmful compounds in the smoke, apparently to produce safer cigarettes without affecting the flavour and nicotine content of the smoke. There are four main types of filters in use today, namely, cellulose acetate, polypropylene, pure cellulose and filters containing granular additives, mainly activated charcoal (1). Cellulose acetate dominates the global filter market with 68 percent. Polypropylene filters follow with 21 percent (almost all of which are in China), charcoal filters comprise 10 percent and cellulose filters comprise less than 1 percent. Since it is difficult in selectively reducing specific compounds, the companies have focused on reducing the tar components, which is thought to contain the unaltered irrespective of whether the charcoal filters were present or replaced by similar length of conventional cellulose acetate filter. Although charcoal filters are commercially available, those are not effective in reducing the p-BSQ of the smoke. Nevertheless, this invention may be considered a re-evaluation and improvement of the existing state of art. Since activated charcoal not only adsorbs p-BSQ but also some tar and nicotine, the said charcoal filter cigarettes may be categorized as relatively low tar, low nicotine mild cigarettes. Apprehending that there might be some smokers who would not like mild cigarettes with low nicotine delivery, the tobacco of some of the said charcoal filter cigarettes will be fortified with nicotine to produce regular cigarettes with comparable nicotine content without any increase in the p-BSQ level of the smoke. Object of the invention The object of the present invention is to provide special activated charcoal filters mainly to reduce from the mainstream smoke p-benzosemiquinone (p-BSQ), a highly reactive major harmful oxidant, which is singly responsible for the oxidative damage of proteins and probably also DNA, thus conceived to pose the greatest health risk. Another object of the invention is to use stipulated amounts of specific grain sizes or mixture of specific grain sizes of activated charcoal to produce potentially less hazardous cigarettes, without significantly affecting the taste and flavour while providing comfortable mouthful of smoke and nicotine delivery. Still another object of the invention is that the said charcoal filter cigarettes should be acceptable to the smokers with marked reduction in health risk. Another object of the invention is to provide a filter device useful in reducing p-BSQ level, which can be used in any type of smoking device. Summary of the invention Accordingly, the present invention provides a filter for a tobacco smoke inhaling/generating/producing device, the filter having three sections placed longitudinally one after another, comprising: a first section comprising cellulose acetate fiber acting as a mouth piece; a second section comprising requisite amounts of specific mesh sizes of activated charcoal selected from the group consisting of charcoal particles having mesh sizes of BS 44/52, BS 52/60, BS 60/72, BS 72/85, and any combinations thereof for effectively reducing p-benzosemiquinone, a highly reactive major harmful oxidant from the mainstream of said tobacco smoke; and a third section comprising cellulose acetate fiber located closer to a tobacco portion, also acting as a barrier between the activated charcoal and tobacco portion, wherein the activated charcoal is selected from the group consisting of 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 52/60, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.15 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 60/72 and 0.1 g of mesh size BS 72/85,0.1 g of mesh size BS 52/60 and 0.05 g of mesh size BS 72/85, and 0.1 g of mesh size BS 60/72 and 0.05 g of mesh size BS 72/85, and any combinations thereof. In accordance to the present invention provides a cigarette smoke filter comprising stipulated amounts of specific grain sizes or combination of grain sizes of activated charcoal for effectively reducing p-benzosemiquinone (p-BSQ) from the mainstream smoke without significantly affecting the taste and flavor while providing comfortable mouthful of smoke and nicotine delivery. p-BSQ is a relatively stable free radical and a highly reactive major harmful oxidant present in the cigarette smoke, which is mainly responsible for the oxidative damage of proteins as well as DNA. The different grain sizes or combination of different grain sizes of activated charcoal have been selected from BS (British standard mesh) 25/44, 44/52, 52/60, 60/72, 72/85 and 85/100. The level of p-BSQ in the smoke from different charcoal filters cigarettes is reduced 55 to 85 percent, which is accompanied by inhibition of BSA oxidation to the extent of 55 to 82 percent. The charcoal filters also effectively reduce nitric oxide 44 to 68 percent and tar 10 to 50 percent from the mainstream smoke. Nicotine delivery, which is reduced to some extent by the charcoal filters, is replenished by fortification of the tobacco with nicotine without any increase in the p-BSQ level of the smoke, apparently because nicotine is not a precursor of p-BSQ. Detailed description of the invention In accordance, the present invention provides a filter for tobacco smoke inhaling/generating/producing device, the said filter comprising three sections placed longitudinally one after another wherein, the first section comprising cellulose acetate fibre acting as a mouth piece, the second section comprising activated charcoal selected from group consisting of charcoal particles having grain size ranging between 25 mesh and 100 mesh for effectively reducing p-benzosemiquinone, a highly reactive major harmful oxidant from the mainstream of cigarette smoke and the third section comprising cellulose acetate fibre located closer to the tobacco portion of the cigarette also acting as a barrier between the activated charcoal and tobacco In embodiment of the invention, wherein length of the first section is in the range of 10 to 14 mm, length of the second section 4.5 mm to 35 mm which is dependent on the grain size and/or amount of charcoal used and length of the third section is in the range of 2 to 3 mm. In another embodiment of the invention, wherein length of the second section is in the range of 4.5 mm to 35mm consisting of one or more activated charcoal particles. In another embodiment of the invention, wherein all the three sections are linearly joined together in succession using a thin wall tube made of light material selected from the group consisting of thin wall plastic tube, paper, plastic wrapped paper and aluminum foil. Still another embodiment of the invention, wherein the activated charcoal filter consisting of charcoal granules which, are placed in a void space between the sections of cellulose acetate filters namely the mouthpiece and the barrier. Still another embodiment of the invention, wherein the amount of charcoal used is in the range between O.lg and 0.6g Yet another embodiment of the invention, each charcoal bed of length 5.0+ 0.5 mm is packed with 0.1 g of charcoal granules. Yet another embodiment of the invention, wherein the activated charcoal used is selected from group consisting of charcoal particles with grain size ranging between 25 mesh and 150 mesh, preferably 100 mesh. Yet another embodiment of the invention, wherein the activated charcoal used is selected from the group consisting of BS 25/44, BS 44/52, BS 52/60, BS 60/72, 72/85 and 85/100 for effectively reducing p-BSQ from the mainstream smoke. Yet another embodiment of the invention, the amount of BS 44/52-grain size charcoal used is in the range of 0.2 to 0.3 g. Yet another embodiment of the invention, the amount of BS 44-grain size charcoal used is up to 0.4g. Yet another embodiment of the invention, the amount of BS 52/60-grain size charcoal used is in the range of 0.2 to 0.3 g. Yet another embodiment of the invention, the amount of BS 60/72-grain size charcoal used is in the range of 0.15 to 0.20 g. Yet another embodiment of the invention, the amount of BS 72/85-grain size charcoal used is in the range of 0.10 to 0.15 g. Yet another embodiment of the invention, the amount of activated charcoal used consists of 0.4 g of BS 44 and 0.2 g of BS 52. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.2 g of BS 44/52 and 0.1 g of BS 52/60. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.2 g of BS 44/52 and 0.1 g of BS 60/72. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.1 g of BS 44/52 and 0.1 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.2 g of BS 44/52 and 0.1 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.15 g of BS 44/52 and 0.1 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.1 g of BS 52/60 and 0.1 g of BS 60/72. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.1 g of BS 52/60 and 0.1 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.1 g of BS 60/72 and 0.1 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of 0.1 g of 52/60 and 0.05 g of BS 72/85. Yet another embodiment of the invention, wherein the activated charcoal mixture used consists of0.l g of BS 60/72 and 0.05 g of BS 72/85. Yet another embodiment of the invention, wherein said filter inhibits p-benzosemiquinone (p-BSQ )of the mainstream smoke up to 85 percent. Yet another embodiment of the invention, wherein the said filter inhibits the protein oxidation, as evidenced by carbonyl formation in BSA by the mainstream cigarette smoke solution up to 89 percent. Yet another embodiment of the invention, wherein said filter reduces nitric oxide (NO) of the mainstream smoke up to 68 percent. Yet another embodiment of the invention, wherein the nicotine delivery in the mainstream smoke is reduced from 935 µg to 350-400 µg per cigarette. Yet another embodiment of the invention, wherein the mainstream smoke solution is incapable of producing significant oxidative damage to guinea pig lung microsomal proteins in vitro One more embodiment of the invention related to use of nicotine fortified tobacco, which results in increase in delivery of nicotine without increasing the level of p-BSQ. Another embodiment of the invention, wherein tobacco fortified with 2 to 4 mg of nicotine increases the nicotine delivery without increasing the level of p-BSQ. Still another embodiment of the invention, wherein tobacco fortified with 2 to 4 mg of nicotine increase the nicotine delivery in the main stream smoke from 350-400 µg to 575- 700 µg without increasing the level of p-BSQ. Still another embodiment of the invention, wherein nicotine fortified tobacco with 2 to 4 mg of nicotine, delivers nicotine up to 90% without increasing the level of p-BSQ. Still another embodiment of the invention, wherein said tobacco inhaling filter device may be used in cigarettes, cigars, pipes, bedi, cigar holders and any other conventional smoking devices. One more embodiment of the invention provides a smoking device for use in a cigarette, said cigarette comprising a tobacco unit and a filter unit, said tobacco unit filled with tobacco particles and said filter unit comprising three sections placed longitudinally one after another wherein, the first section comprising cellulose acetate fibre acting as a mouth piece, the second section comprising activated charcoal and the third section comprising cellulose acetate fibre located abutting the tobacco portion of the cigarette this acting as a barrier between the activated charcoal and tobacco. Yet another embodiment of the invention, wherein the smoke from activated charcoal filter of cigarettes, cigars, pipes, cigar holders or any other conventional smoking devices exhaled by smokers containing markedly low level of p-BSQ is potentially less hazardous to passive smokers. Yet another embodiment of the invention, wherein the mainstream cigarette smoke containing very low level of p-BSQ is incapable of producing significant oxidative damage to the lung microsomal proteins of guinea pigs in vivo when the animals are exposed to smoke emitted from the said charcoal - filtered cigarettes in contrast to marked damage of the lung tissue when the animal are exposed to smoke from cigarettes without having the said charcoal filter. The invention is described with reference to the examples, which are provided by way of illustration only, and these examples should not be construed to limit the scope of the present invention. Brief description of the accompanying drawings Figure 1 represents a typical charcoal filter cigarette, wherein (1) Conventional cellulose acetate fibre filter, acting as the mouthpiece, the length of which may vary according to convenience, e.g. 10-15 mm. (2) Conventional cellulose acetate fibre filter, acting as a barrier between the charcoal bed and the tobacco portion to prevent infiltration of charcoal into tobacco, the length of which may be 2-4 mm. The length of the activated charcoal bed can vary depending on the amount of charcoal used, e.g. 4.5-5.5 mm per 100 mg, 9-11 mm % 200 mg and 13-16 mm per 300 mg charcoal etc., Figure 2 represents a graphical representation of carbonyl formation in BSA by p-BSQ. Figure 3 represents SDS-PAGE showing protective effect of charcoal filters on the cigratte smoke induced oxidative degradation of guinea pig lung microsomal proteins, wherein, lane 1, microsomes incubated in the absence of cigarette smoke solution; lane 2, microsomes incubated in the presence of solution of smoke from cigarettes without any charcoal filter; lanes 3-5, microsomes incubated with smoke solution form cigarettes having charcoal filters; lane 3, BS 52/60, 0.3 g; lane 4, a mixture of BS 44/52, 0.2 g and BS 72/85 ,0.1 g, lane 5, a mixture of BS 60/72, 0.1 g and BS72/85, 0.1 g; In each case, the microsomal suspension (1 mg protein) was incubated with 50 µl smoke solution in a final volume of 20 µl of 50 mM potassium phosphate buffer, pH 7.4 for 2 hours at 37°C. After incubation, 40µl of the incubation mixture was subjected to 10% SDS-PAGE. The gel was stained with Coomassie Brilliant Blue R-250 Figure 4 represents SDS-PAGE of lung microsomal proteins of normal guinea pigs and guinea pigs exposed to smoke from cigarettes with and without charcoal filter, wherein. Lane 1 - Lung microsomes of normal guinea pigs Lane 2 - Lung microsomes of guinea pigs exposed to smoke from cigarettes without charcoal filter Lane 3- Lung microsomes of guinea exposed to smoke from cigarettes equipped with activated charcoal filter containing a mixture of 0.1 g of BS 52/60 and 0.lg of BS 60/72 Brief description of the tables appearing at the end of the description is given below: Table 1. p-Benzosemiquinone (p-BSQ), BSA oxidation, nicotine delivery and tar contents in the smoke solution from an Indian commercial cigarette with stipulated amounts of different grain sizes of activated charcoal. Table 2. Effect of fortification of tobacco of the charcoal filter cigarettes with nicotine on the p-BSQ, tar and nicotine delivery in the smoke solution of the smoke from an Indian commercial cigarette Table 3. Effects of charcoal filters on the nitric oxide level in the smoke solution from an Indian commercial cigarette. Table 4. Inactivation of the major harmful cs-oxidant and nicotine delivery in cigarette smoke using activated charcoal filter Methodology Construction of activated charcoal filter The activated charcoal filter was constructed by placing stipulated amounts of different grain sizes or mixture of grain sizes of activated charcoal in a thin plastic tube, the inside diameter of which was same as the outside diameter of the tobacco portion of the cigarette or the conventional cellulose acetate filter. The plastic tube could be replaced by tubes manufactured of light grade materials, namely hard paper tube, plastic wrapped paper tube or tube made with aluminium foil. At the one end of the tube containing the charcoal was inserted the conventional cellulose acetate filter (approximately 10 - 14 mm) which constitutes the mouthpiece and at the other end was inserted the tobacco portion of the cigarette (approximately 63 mm). A thin section of cellulose acetate filter (approximately 3 mm) was placed in the cavity in between the tobacco portion and charcoal bed as depicted in the drawing (Fig. 1). Essentially, the charcoal filter is a cavity filter where the activated charcoal granules are placed in a void space between two segments of cellulose acetate filters. As mentioned above, one portion of the cellulose acetate filter (l0 - 14 mm) is the mouthpiece and other portion (3 mm) constitutes a barrier between the charcoal bed and the tobacco portion (Fig. 1). The portions, namely, the cellulose acetate mouth piece, the charcoal filter, the thin cellulose acetate filter placed in between the charcoal and the tobacco portion and the tobacco portion all are constructed into one single unit (Fig. 1). The cellulose acetate filter does not necessarily improve the filtration of p-BSQ of the smoke. However, its use in cooperation with the charcoal filter adds to the convenience of using it as a mouthpiece for suction. The thin section of the cellulose acetate filter placed in between the charcoal and the tobacco portion was used to prevent any infiltration of charcoal granules into the tobacco of the cigarette. The length of the charcoal packed in the filter corresponded approximately to the weight of the charcoal used. The weight to length proportion was usually 100 mg charcoal corresponding to 5 mm, 200 mg charcoal, 20 mm and so on. The total length of a charcoal filter cigarette using 300 mg of charcoal is 91 mm [10 mm cellulose acetate filter as a mouthpiece, 15 mm charcoal bed, 3 mm cellulose acetate as a partition between charcoal bed and tobacco portion and 63 mm tobacco portion]. The length of the cellulose acetate may be varied, because it is practically ineffective in reducing p-BSQ of the smoke. The grain size of charcoal used has been expressed in the British Standard (BS) mesh. The size BS 25/44 means particles passing through mesh 25 but retained on mesh 44. Similarly, BS 44/25 means particles passing through mesh 44 but retained on mesh 52. All other grain sizes used in this invention, namely BS 52/60, 60/72 and 72/85 are explained in the same way. The length of the charcoal filter can be varied up to 35 mm, length of conventional filter i.e. cellulose acetate filter can be up to 13 mm for cigarette tobacco length of about 63 mm. (Table 4) Measurement of p-benzosemiquinone (p-BSQ) p-BSQ was quantitatively measured by HPLC as described before (5). Five to ten micro liters of the filtered smoke solution was diluted with mobile phase and 20 µl of this diluted solution was injected to the HPLC column with the UV detector set at 294 nm. The parameters used are as follows. Instrument : Simadzu l0A Column : Silica column (Lichrospher ® Si60, Merck) Mobile phase : Methylene chloride : methanol (90 : 10, v/v) Flow rate : 0.5 ml / min Pressure 29Kgf/cm2 Retention time : 8.808 The amount of p-BSQ present in the smoke solution was calculated from the peak area, taking 100 ng of p-BSQ corresponding to an arbitrary area of 1,90,000 obtained from a standard curve. The efficacy of activated charcoal filters was also determined by measuring the comparative yields of p-BSQ. p-BSQ was isolated from cigarette smoke solution by fractional solvent extraction followed by band TLC as described before (5). After proper dilution of the TLC band extract with the mobile phase, 20µl of the diluted solution was injected to the HPLC column. p-BSQ was detected at 288 nm, which is the Xmax of p- BSQ in the mobile phase used. The parameters used are as follows. Instrument : Simadzu l0A Column : Lichrospher ® 100 RP-18 endcapped (5µm), Merck Mobile phase : Water : methanol (95 : 5, v /v) Flow rate : 0.5 ml / min Pressure : 38Kgf/cm2 Retention time : 7.242 min Measurement of oxidative damage of proteins Protein oxidation as evidenced by carbonyl formation was measured by reaction with 2,4- dinitrophenyl hydrazine similar to that done before in our laboratory (4). When BSA was used, the values were expressed as nmoles of carbonyl formed per mg BSA. The incubation system contained 1 mg BSA and 50 µ1 of smoke solution obtained from cigarettes with or without charcoal filter in a final volume of 200 µl of 50mM potassium phosphate buffer, pH 7.4. After incubation for 1 hr. at 37°C, the protein was precipitated with 200 111 of trichloroacetic acid solution and the rest of the procedure followed as before (4). Oxidative damage of proteins was also measured by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of guinea lung microsomal proteins as described before (4). Preparation of microsomes Guinea pig lung microsomes, washed free of ascorbic acid, were prepared as described before (4). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) SDS-PAGE of microsomal proteins was performed by the procedures similar to that described before (4). Measurement of nicotine Smoke from a lit cigarette was allowed to dissolve in 2 ml of 50mM potassium phosphate buffer, pH 7.4 and filtered through 0.45 µm Millipore filter as described before (5). One milliliter of the yellow coloured filtrate was extracted with one milliliter of methylene chloride by vigorous vortexing to extract the nicotine in the methylene chloride layer. Five hundred microliter of the methylene chloride layer containing the nicotine was then vortexed with 500 µl of 50 mM HCl solution and the nicotine of the HCl solution was estimated by HPLC analysis at 254 nm. Five to 10 µl of the nicotine solution was diluted to 200 µl with the mobile phase and 20 µlof this diluted solution was injected to the HPLC column. A standard solution of nicotine was prepared in a similar way and analyzed. The parameters used are: Instrument : Shimadzu l0A Column : Lichrospher® 100 RP-18 endcapped (5 µm), Merck Mobile phase : 50 mM KH2PO4 solution: accetonitrile : methanol; (78 : 17 : 5, v/v) containing 1 mM sodium hepatane sulfonate, pH 5.0 Flow rate : 0.3 ml / min Pressure : 24Kgf/cm2 Temperature : 250C Retention time : 4.185 min. The minimum amount of nicotine that could be detected by the HPLC analysis under the conditions was 10 ng. Measurement of tar Tar was collected by placing a Millipore filter unit between the lit cigarette with or without charcoal filter and the tube connected to a vacuum pump (LKB, Sweden) using a suction of 30cm water. The Millipore filter (0.22 µm) was changed every two minutes to avoid clogging of the filter. For each cigarette, 4 filters were used. After complete burning of the tobacco, the filters were dried in a vacuum desiccator and weighed. The difference in weight of the filters before and after collecting the particulate portion was the weight of the tar. Measurement of nitric oxide in cigarette smoke solution Ten milliliter of air saturated 50-mM potassium phosphate buffer, pH 7.4 was taken in a 50 ml boiling tube with a side arm and a stopper with a hole. An Indian commercial cigarette was mounted in a tube that penetrated the hole in the stopper and dipped down in the buffer solution. The side arm was connected to a water pump. The cigarette was lit and the smoke from the whole cigarette was bubbled through the buffer solution by applying a suction of 4 cm water. A portion of the cigarette smoke solution thus produced was filtered through a 0.45 µm Millipore filter and extracted thrice with equal volume of methylene chloride. The concentration of potassium nitrite in the aqueous layer was measured after proper dilution by diazotization using Griess regent. A standard solution of NaNO2 was run side by side. Exposure of guinea pigs to cigarette smoke The exposure of the animals to cigarette smoke was done according to a procedure standardized in our laboratory (19). The guinea pigs were grouped as follows: Group 1: Control guinea pigs Group 2: Guinea pigs subjected to smoke from cigarettes without charcoal filter Group 3: Guinea pigs subjected to smoke from cigarettes equipped with activated charcoal filter containing a mixture of 0.1 g of BS 52/60 and 0.lg of BS 60/72. The animals were exposed to cigarette smoke from five cigarettes /animal/day for seven days following the procedure published before (19). The animals were fasted overnight, sacrificed on the eighth day, tissue excised, microsomes prepared and subsequently subjected to SDS-PAGE as described earlier (19). Results Effects of charcoal filters on the p-BSQ, tar and nicotine contents of the mainstream smoke as well as inhibition of protein oxidation Using charcoal filter comprising stipulated amounts of different grain sizes or mixture of grain sizes of activated charcoal, the p-BSQ contents of the mainstream smoke are markedly reduced (Table 1). We have indicated before (5) that among all the compounds present in the smoke solution, only p-BSQ is singly responsible for protein oxidation. Fig. 2 shows that oxidation of BSA, as evidenced by carbonyl formation, is almost quantitatively correlated with the contents of p-BSQ present in the incubation medium. As would be expected, reduction of p-BSQ content in the smoke by the use of charcoal filter is accompanied by marked inhibition of BSA oxidation (Table 1). Use of charcoal filter also results in reduction of some tar and nicotine (Table 1). The most effective grain sizes of activated charcoal, expressed in British Standard (BS) mesh, are 44/52, 52/60, 60/72 and 72/85 used singly or in combination. Grain sizes larger than 44/52, namely 25/44 and 10/25 are not efficient even when used in comparatively large amounts. Use of large amounts of charcoal (0.4 g to 1.0 g) causes problem in suction of the smoke. Use of coconut shell activated charcoal did not have any added advantage over commercially available activated charcoal. The most effective charcoal filters, those markedly reduce p-BSQ content in the smoke without significantly affecting the suction and providing comfortable mouthful of smoke, as evidenced by a panel of middle aged smokers, are given in the Table 1. The charcoal filters comprise 0.2 and 0.3 g of BS 44/52, 0.2 and 0.3 g of BS 52/60, 0.15 and 0.2 g of BS 60/72, 0.1 and 0.15 g of BS 72/85, a mixture of 0.2 g of BS 44/52 and 0.1 g of BS 52/60, a mixture of 0.2 g of BS 44/52 and 0.1 g of BS 60/72, a mixture of 0.1 g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.2g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.15 g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.1 g of BS 52/60 and 0.1 g of BS 60/72, a mixture of 0.1 g of BS 52/60 and 0.1 g of 72/85, and a mixture of 0.1 g of BS 60/72 and 0.1 g of BS 72/85, a mixture of 0.1 g of BS 52/60 and 0.05 g of BS 72/85, and a mixture of 0.1 g of BS 60/72 and 0.05 g of BS 72/85.. With the said charcoal filters, reduction of p-BSQ was in the range of 55 to 85 percent, with a corresponding inhibition of BSA oxidation was in the range of 55 to 82 percent. Effect of fortification of tobacco of the charcoal filter cigarettes with nicotine on the p-BSQ, tar and nicotine delivery of the smoke from an Indian commercial cigarette Table 1 shows that the charcoal filter cigarettes mentioned in this invention are very effective for markedly reducing the content of p-BSQ, the major hazardous oxidant present in the mainstream smoke. Table 1 further shows that the tar and nicotine delivery of these charcoal filter cigarettes are also considerably reduced. These charcoal filter cigarettes may therefore be considered as potentially safer mild cigarette. Apprehending that there might be some committed smokers who would not like mild cigarette with low nicotine delivery, the tobacco of some of the charcoal filter cigarettes has been fortified with 2 mg nicotine per cigarette and the results are given in Table 2. The results indicate that fortification of tobacco with 2 mg nicotine per cigarette lead to increase the nicotine delivery of the smoke considerably. The increase in nicotine delivery is accompanied by increase in tar content (Table 2). Fortification of tobacco with 3-4 mg nicotine produces about 30 - 50 percent more nicotine delivery (results not shown). However, fortification of tobacco with nicotine does not lead to any increase of p-BSQ content of the smoke, apparently because nicotine is not a precursor of p-BSQ and it does not contribute to either the level of p-BSQ in smoke or oxidation of BSA by the smoke solution (Table 2). The results would indicate that although fortification of tobacco with nicotine of the charcoal filter cigarettes results in increased nicotine delivery, but the said charcoal filter cigarettes remain potentially safer cigarettes. Effects of charcoal filters on the nitric oxide level in the smoke solution from an Indian commercial cigarette Nitric oxide (NO) is one of the most important free radicals in the gas phase of cigarette smoke. Some scientists think that NO may be implicated in the development of chronic obstructive pulmonary disease and emphysema in the smokers. Results presented in Table 3 indicates that activated charcoal filter is very effective in reducing the NO level in the mainstream smoke. Using a mixture 0.2 g of BS 44/52 and 0.1 g of BS 72/85, the percent inhibition in the NO is as high as 68. Protective effect of charcoal filters on the cigarette smoke induced oxidative degradation of guinea pig lung microsomal proteins in vitro Fig. 3 (lane 2) shows that cigarette smoke solution obtained from an Indian commercial cigarette causes extensive damage of guinea pig lung microsomal proteins as evidenced by SDS-PAGE. The figure further shows that the oxidative damage of microsomal proteins is markedly reduced when the said cigarette was equipped with activated charcoal filters, namely, BS 52/60, 0.3 g (lane 3); a mixture of BS 44/52, 0.2g and BS 72/85, O.lg (lane 4); a mixture of BS 60/72, O.lg and BS 72/85, O.lg (lane 5). Protective effect of charcoal filter on the cigarette smoke induced oxidative damage of guinea pig lung microsomal proteins in vivo Fig 4 (lane 2) shows that after exposure of the guinea pigs to cigarette smoke, lung microsomal proteins are discemibly damaged, as evidenced by SDS-PAGE. The oxidative damage is significantly protected when the animals are exposed to smoke from cigarettes equipped with activated charcoal filter containing a mixture of O.lg of BS 52/60 and O.lg of BS 60/72. Table 1 p-6enzosemiquinone (p-BSQ), BSA oxidation, nicotine delivery and tar contents in the smoke solution from an Indian commercial cigarette with stipulated amounts of different grain sizes of activated charcoal (Table Removed) a, British standard b, BS 44/52 means particles passing through mesh 44, but retained on mesh 52. All other grain sizes mentioned in the Table are explained in the same way. c, Indicates mixture of the two grain sizes d, Amount of carbonyl formed by 50 µl of smoke solution. Details of the incubation system and measurement of carbonyl are given under Methodology Section. Table 2. Effect of fortification of tobacco of the charcoal filter cigarettes with nicotine on the p-BSQ, tar and nicotine delivery in the smoke solution from an Indian commercial cigarette (Table Removed) * Values are means of four determinations; SD + Fortification of the tobacco with 3 mg nicotine instead of 2 mg nicotine results in about 30 percent more delivery of nicotine in the smoke (results not shown) Table 3. Effects of charcoal filters on the nitric oxide level in the smoke solution from an Indian commercial cigarette (Table Removed) Table 4. Inactivation of the major harmful cs-oxidant and nicotine deliverv in cigarette smoke using activated charcoal filter (Table Removed) * Internal diameter of the charcoal filter was 8 mm. ** The percentage was calculated taking nicotine delivered (940 µg + 40 S.D; n=6) from cigarette with conventional filter as 100 # BS 44 indicates BS 25 (-) to BS 44 (+), particle size of 350 - 700 µm # BS 52 indicates BS 44 (-) to BS 52 (+), particle size of 250 - 350 µm 0 26 ram BS 44 + 9 mm BS 52 ♦ The lengths of the conventional filters have been depicted in Figs. 36 and 37. References 1 http://www.tobaccoreporter.com/backissues/Dec2000/Dec2000 feature 2.asp 2 Denissenko, M.F., Pao, A., Tang, M.S. and Pfeifer, G.P. Science 274,430-432 (1996) 3 Hecht, S.S., Spratt, T.E and Trushin, N. Carcinogenesis 9, 161-165 (1988) 4 Panda, K., Chattopadhyay, R., Ghosh, M.K., Chattopadhyay, D.J. and Chatterjee, LB., Free Radic. Biol. Med. 27. 1064-1079 (1999) 5 Chatterjee, I.B., Indian Patent Application No 701/DEL/2001 6 Nagata,., Kodama, M. and loki, Y. in Polycyclic Hydrocarbons and Cancer, Gelboin, H.V. and Ts'O, P.O.P. Eds (Academic Press, New York), 1, 247 (1978) 7 Pryor, W.A., Environ. Health Perspect 105. Suppl. 4, 1, (1997) 8 Church, D.F. and Pryor, W.A. Environ. Health Perspect. 64, 11 1-126 (1985) 9 http://www.law. Indiana, edu/ ilj/ v73/ no 3/ givelber.html 10 Stavridis et. al. US Patent NO. 5,909,736, June 8,(1999) 11 Osaga et. al. US Patent NO.4,038,992, August 2,(1977) 12 Innacelli, US Patent NO. 4,373,539, February 15, 1983 13 WO Patent No. 9600019 14 US Patent No. 5360023 15 US Patent No. 3658069 16 http://www. starscientific.com/066745321909/advancefilter.html 17 http: //www.ryomagazine. com/october/filters .htm 18 www.baumgartnerinc.com/whatsnew.htm 19 Panda, K., Chattopadhyay, R., Chattopadhyay, D.J. and Chatterjee, I.B., Free Radic. Biol. Med. 29, 115 - 124 (2000) We Claim: 1. A filter for a tobacco smoke inhaling/generating/producing device, the filter having three sections placed longitudinally one after another, comprising: a first section comprising cellulose acetate fiber acting as a mouth piece; a second section comprising requisite amounts of specific mesh sizes of activated charcoal selected from the group consisting of charcoal particles having mesh sizes of BS 44/52, BS 52/60, BS 60/72, BS 72/85, and any combinations thereof for effectively reducing p-benzosemiquinone, a highly reactive major harmful oxidant from the mainstream of said tobacco smoke; and a third section comprising cellulose acetate fiber located closer to a tobacco portion, also acting as a barrier between the activated charcoal and tobacco portion, wherein the activated charcoal is selected from the group consisting of 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 52/60, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.15 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 60/72 and 0.1 g of mesh size BS 72/85,0.1 g of mesh size BS 52/60 and 0.05 g of mesh size BS 72/85, and 0.1 g of mesh size BS 60/72 and 0.05 g of mesh size BS 72/85, and any combinations thereof. 2. A filter as claimed in claim 1, wherein the length of the first section is in the range of 10 to 14 mm. 3. A filter as claimed in claim 1, wherein the length of the second section is dependent on the mesh size and/or amount of charcoal used. 4. A filter as claimed in claim 1, wherein the length of the second section is in the range of 4.5 mm to 35 mm. 5. A filter as claimed in claim 1, wherein the length of the third section is in the range of 2 to 3 mm. 6. A filter as claimed in claim 1, wherein all the three sections are linearly joined together in succession using a thin wall tube made of lightweight material selected from the group consisting of thin wall plastic tube, paper, plastic wrapped paper and aluminum foil. 7. A filter as claimed in claim 1, wherein requisite amounts of specific mesh sizes of the activated charcoal ranging between BS 44/52 and BS 72/85 mesh are placed in a void space between the sections of cellulose acetate filters namely the mouthpiece and the barrier. 8. A filter as claimed in claim 1, wherein the amount of charcoal used is in the range between 0.1 g and 0.3 g. 9. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.3 g of the mesh size BS 44/52. 10. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.2 g of the mesh size BS 52/60. 11. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.3 g of the mesh size BS 52/60. 12. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.15 g of the mesh size BS 60/72. 13. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.2 g of the mesh size BS 60/72. 14. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.15 g of the mesh size BS 72/85. 15. A filter as claimed in claim 1, wherein said filter is used in smoking devices selected from group consisting of cigarettes, cigarette holders, pipes and any other smoking devices. 16. A filter for a tobacco smoke inhaling/generating/producing device substantially as herein described with the references to the examples accompanying the specification.

Full Text

A FILTER FOR A TOBACCO SMOKE INHALING/GENERATING/PRODUCING
DEVICE
Filed of the invention
The present invention relates to an activated charcoal based tobacco smoke filter device, for effectively reducing level of p-benzosemiquinone (p-BSQ) a highly reactive major harmful oxidant from the mainstream cigarette smoke while providing comfortable mouthful of smoke and nicotine delivery with considerable reduction in health risk-to the smokers. The said device also reduces other components of the tobacco smoke such as nitric oxide, nicotine etc.
Background and prior art references
Cigarette smoking is the world's single most preventable cause of disease and death.
Worldwide, about 36 percent of all adults smoke cigarettes. According to a 1999 World Health Organization estimate, there are 4 million deaths a year from tobacco. Tobacco smoke contains more than 4000 compounds. Among these, nicotine is the habit forming pharmacological agent. Others are toxins, mutagens and carcinogens that cause or enhance various degenerative diseases including cancer of lung and other organs, chronic obstructive pulmonary disease such as bronchitis and emphysema as well as heart disease and stroke. Since approaches to cessation of smoking by public health campaigns and anti-smoking laws passed by local Governments have had limited success, the most practicable approach is the prevention of the hazardous effects caused by cigarette smoke. Modification of the cigarette is in itself a practical approach to reducing the toxic compounds contained in cigarette smoke. One of the approaches was to use cigarette filters. This is what the cigarette manufacturers have been trying to do for the last few decades.
The cigarette companies have introduced cigarettes with filter tips to reduce the harmful compounds in the smoke, apparently to produce safer cigarettes without affecting the flavour and nicotine content of the smoke. There are four main types of filters in use today, namely, cellulose acetate, polypropylene, pure cellulose and filters containing granular additives, mainly activated charcoal (1). Cellulose acetate dominates the global filter market with 68 percent. Polypropylene filters follow with 21 percent (almost all of which are in China), charcoal filters comprise 10 percent and cellulose filters comprise less than 1 percent. Since it is difficult in selectively reducing specific compounds, the companies have focused on reducing the tar components, which is thought to contain the

unaltered irrespective of whether the charcoal filters were present or replaced by similar length of
conventional cellulose acetate filter.
Although charcoal filters are commercially available, those are not effective in reducing the p-BSQ of the
smoke. Nevertheless, this invention may be considered a re-evaluation and improvement of the existing state
of art. Since activated charcoal not only adsorbs p-BSQ but also some tar and nicotine, the said charcoal filter
cigarettes may be categorized as relatively low tar, low nicotine mild cigarettes. Apprehending that there
might be some smokers who would not like mild cigarettes with low nicotine delivery, the tobacco of some
of the said charcoal filter cigarettes will be fortified with nicotine to produce regular cigarettes with
comparable nicotine content without any increase in the p-BSQ level of the smoke.
Object of the invention
The object of the present invention is to provide special activated charcoal filters mainly to reduce from the
mainstream smoke p-benzosemiquinone (p-BSQ), a highly reactive major harmful oxidant, which is singly
responsible for the oxidative damage of proteins and probably also DNA, thus conceived to pose the greatest
health risk.
Another object of the invention is to use stipulated amounts of specific grain sizes or mixture of specific
grain sizes of activated charcoal to produce potentially less hazardous cigarettes, without significantly
affecting the taste and flavour while providing comfortable mouthful of smoke and nicotine delivery.
Still another object of the invention is that the said charcoal filter cigarettes should be acceptable to the
smokers with marked reduction in health risk.
Another object of the invention is to provide a filter device useful in reducing p-BSQ level, which can be
used in any type of smoking device.
Summary of the invention
Accordingly, the present invention provides a filter for a tobacco smoke inhaling/generating/producing
device, the filter having three sections placed longitudinally one after another, comprising: a first section comprising cellulose acetate fiber acting as a mouth piece; a second section comprising requisite amounts of specific mesh sizes of activated charcoal selected from the group consisting of charcoal particles having mesh sizes of BS 44/52, BS 52/60, BS 60/72, BS 72/85, and any combinations thereof for effectively reducing p-benzosemiquinone, a highly reactive major harmful oxidant from the mainstream of said tobacco smoke; and a third section comprising cellulose acetate fiber located closer to a tobacco portion, also acting as a barrier between the activated charcoal and tobacco portion, wherein the activated charcoal is selected from the group consisting of 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 52/60, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.15 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 60/72 and 0.1 g of mesh size BS 72/85,0.1 g of mesh size BS 52/60 and 0.05 g of mesh size BS 72/85, and 0.1 g of mesh size BS 60/72 and 0.05 g of mesh size BS 72/85, and any combinations thereof.
In accordance to the present invention provides a cigarette smoke filter comprising stipulated amounts of specific grain sizes or combination of grain sizes of activated charcoal for effectively reducing p-benzosemiquinone (p-BSQ) from the mainstream smoke without significantly affecting the taste and flavor while providing comfortable mouthful of smoke and nicotine delivery. p-BSQ is a relatively stable free radical and a
highly reactive major harmful oxidant present in the cigarette smoke, which is mainly
responsible for the oxidative damage of proteins as well as DNA. The different grain sizes
or combination of different grain sizes of activated charcoal have been selected from BS
(British standard mesh) 25/44, 44/52, 52/60, 60/72, 72/85 and 85/100. The level of p-BSQ
in the smoke from different charcoal filters cigarettes is reduced 55 to 85 percent, which is
accompanied by inhibition of BSA oxidation to the extent of 55 to 82 percent. The
charcoal filters also effectively reduce nitric oxide 44 to 68 percent and tar 10 to 50 percent
from the mainstream smoke. Nicotine delivery, which is reduced to some extent by the
charcoal filters, is replenished by fortification of the tobacco with nicotine without any
increase in the p-BSQ level of the smoke, apparently because nicotine is not a precursor of
p-BSQ.
Detailed description of the invention
In accordance, the present invention provides a filter for tobacco smoke
inhaling/generating/producing device, the said filter comprising three sections placed
longitudinally one after another wherein, the first section comprising cellulose acetate fibre
acting as a mouth piece, the second section comprising activated charcoal selected from
group consisting of charcoal particles having grain size ranging between 25 mesh and 100
mesh for effectively reducing p-benzosemiquinone, a highly reactive major harmful
oxidant from the mainstream of cigarette smoke and the third section comprising cellulose
acetate fibre located closer to the tobacco portion of the cigarette also acting as a barrier
between the activated charcoal and tobacco
In embodiment of the invention, wherein length of the first section is in the range of 10 to
14 mm, length of the second section 4.5 mm to 35 mm which is dependent on the grain
size and/or amount of charcoal used and length of the third section is in the range of 2 to 3
mm.
In another embodiment of the invention, wherein length of the second section is in the
range of 4.5 mm to 35mm consisting of one or more activated charcoal particles.
In another embodiment of the invention, wherein all the three sections are linearly joined
together in succession using a thin wall tube made of light material selected from the group
consisting of thin wall plastic tube, paper, plastic wrapped paper and aluminum foil.
Still another embodiment of the invention, wherein the activated charcoal filter consisting
of charcoal granules which, are placed in a void space between the sections of cellulose
acetate filters namely the mouthpiece and the barrier.
Still another embodiment of the invention, wherein the amount of charcoal used is in the
range between O.lg and 0.6g
Yet another embodiment of the invention, each charcoal bed of length 5.0+ 0.5 mm is
packed with 0.1 g of charcoal granules.
Yet another embodiment of the invention, wherein the activated charcoal used is selected
from group consisting of charcoal particles with grain size ranging between 25 mesh and
150 mesh, preferably 100 mesh.
Yet another embodiment of the invention, wherein the activated charcoal used is selected
from the group consisting of BS 25/44, BS 44/52, BS 52/60, BS 60/72, 72/85 and 85/100
for effectively reducing p-BSQ from the mainstream smoke.
Yet another embodiment of the invention, the amount of BS 44/52-grain size charcoal used
is in the range of 0.2 to 0.3 g.
Yet another embodiment of the invention, the amount of BS 44-grain size charcoal used is
up to 0.4g.
Yet another embodiment of the invention, the amount of BS 52/60-grain size charcoal used
is in the range of 0.2 to 0.3 g.
Yet another embodiment of the invention, the amount of BS 60/72-grain size charcoal used
is in the range of 0.15 to 0.20 g.
Yet another embodiment of the invention, the amount of BS 72/85-grain size charcoal used
is in the range of 0.10 to 0.15 g.
Yet another embodiment of the invention, the amount of activated charcoal used consists
of 0.4 g of BS 44 and 0.2 g of BS 52.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.2 g of BS 44/52 and 0.1 g of BS 52/60.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.2 g of BS 44/52 and 0.1 g of BS 60/72.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.1 g of BS 44/52 and 0.1 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.2 g of BS 44/52 and 0.1 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.15 g of BS 44/52 and 0.1 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.1 g of BS 52/60 and 0.1 g of BS 60/72.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.1 g of BS 52/60 and 0.1 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.1 g of BS 60/72 and 0.1 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of 0.1 g of 52/60 and 0.05 g of BS 72/85.
Yet another embodiment of the invention, wherein the activated charcoal mixture used
consists of0.l g of BS 60/72 and 0.05 g of BS 72/85.
Yet another embodiment of the invention, wherein said filter inhibits p-benzosemiquinone
(p-BSQ )of the mainstream smoke up to 85 percent.
Yet another embodiment of the invention, wherein the said filter inhibits the protein
oxidation, as evidenced by carbonyl formation in BSA by the mainstream cigarette smoke
solution up to 89 percent.
Yet another embodiment of the invention, wherein said filter reduces nitric oxide (NO) of
the mainstream smoke up to 68 percent.
Yet another embodiment of the invention, wherein the nicotine delivery in the mainstream
smoke is reduced from 935 µg to 350-400 µg per cigarette.
Yet another embodiment of the invention, wherein the mainstream smoke solution is
incapable of producing significant oxidative damage to guinea pig lung microsomal
proteins in vitro
One more embodiment of the invention related to use of nicotine fortified tobacco, which
results in increase in delivery of nicotine without increasing the level of p-BSQ.
Another embodiment of the invention, wherein tobacco fortified with 2 to 4 mg of nicotine
increases the nicotine delivery without increasing the level of p-BSQ.
Still another embodiment of the invention, wherein tobacco fortified with 2 to 4 mg of
nicotine increase the nicotine delivery in the main stream smoke from 350-400 µg to 575-
700 µg without increasing the level of p-BSQ.
Still another embodiment of the invention, wherein nicotine fortified tobacco with 2 to 4
mg of nicotine, delivers nicotine up to 90% without increasing the level of p-BSQ.
Still another embodiment of the invention, wherein said tobacco inhaling filter device may
be used in cigarettes, cigars, pipes, bedi, cigar holders and any other conventional smoking
devices.
One more embodiment of the invention provides a smoking device for use in a cigarette,
said cigarette comprising a tobacco unit and a filter unit, said tobacco unit filled with
tobacco particles and said filter unit comprising three sections placed longitudinally one
after another wherein, the first section comprising cellulose acetate fibre acting as a mouth
piece, the second section comprising activated charcoal and the third section comprising
cellulose acetate fibre located abutting the tobacco portion of the cigarette this acting as a
barrier between the activated charcoal and tobacco.
Yet another embodiment of the invention, wherein the smoke from activated charcoal filter
of cigarettes, cigars, pipes, cigar holders or any other conventional smoking devices
exhaled by smokers containing markedly low level of p-BSQ is potentially less hazardous
to passive smokers.
Yet another embodiment of the invention, wherein the mainstream cigarette smoke
containing very low level of p-BSQ is incapable of producing significant oxidative damage
to the lung microsomal proteins of guinea pigs in vivo when the animals are exposed to
smoke emitted from the said charcoal - filtered cigarettes in contrast to marked damage of
the lung tissue when the animal are exposed to smoke from cigarettes without having the
said charcoal filter.
The invention is described with reference to the examples, which are provided by way of
illustration only, and these examples should not be construed to limit the scope of the
present invention.
Brief description of the accompanying drawings
Figure 1 represents a typical charcoal filter cigarette, wherein
(1) Conventional cellulose acetate fibre filter, acting as the mouthpiece, the length of which may vary according to convenience, e.g. 10-15 mm. (2) Conventional cellulose acetate fibre filter, acting as a barrier between the charcoal bed and the tobacco portion to prevent infiltration of charcoal into tobacco, the length of which may be 2-4 mm. The length of the activated charcoal bed can vary depending on the amount of charcoal used, e.g. 4.5-5.5 mm per 100 mg, 9-11 mm % 200 mg and 13-16 mm per 300 mg charcoal etc.,
Figure 2 represents a graphical representation of carbonyl formation in BSA by p-BSQ.
Figure 3 represents SDS-PAGE showing protective effect of charcoal filters on the cigratte smoke induced oxidative degradation of guinea pig lung microsomal proteins, wherein, lane 1, microsomes incubated in the absence of cigarette smoke solution; lane 2, microsomes incubated in the presence of solution of smoke from cigarettes without any charcoal filter; lanes 3-5, microsomes incubated with smoke solution form cigarettes having charcoal filters; lane 3, BS 52/60, 0.3 g; lane 4, a mixture of BS 44/52, 0.2 g and BS 72/85 ,0.1 g, lane 5, a mixture of BS 60/72, 0.1 g and BS72/85, 0.1 g; In each case, the microsomal suspension (1 mg protein) was incubated with 50 µl smoke solution in a final volume of 20 µl of 50 mM potassium phosphate buffer, pH 7.4 for 2 hours at 37°C. After incubation, 40µl of the incubation mixture was subjected to 10% SDS-PAGE. The gel was stained with Coomassie Brilliant Blue R-250
Figure 4 represents SDS-PAGE of lung microsomal proteins of normal guinea pigs and guinea pigs exposed to smoke from cigarettes with and without charcoal filter, wherein.
Lane 1 - Lung microsomes of normal guinea pigs Lane 2 - Lung microsomes of guinea pigs exposed to smoke from cigarettes
without charcoal filter Lane 3- Lung microsomes of guinea exposed to smoke from cigarettes equipped with activated charcoal filter containing a mixture of 0.1 g of BS 52/60 and 0.lg of BS 60/72
Brief description of the tables appearing at the end of the description is given below:
Table 1. p-Benzosemiquinone (p-BSQ), BSA oxidation, nicotine delivery and tar
contents in the smoke solution from an Indian commercial cigarette with
stipulated amounts of different grain sizes of activated charcoal.
Table 2. Effect of fortification of tobacco of the charcoal filter cigarettes with
nicotine on the p-BSQ, tar and nicotine delivery in the smoke solution of
the smoke from an Indian commercial cigarette
Table 3. Effects of charcoal filters on the nitric oxide level in the smoke solution
from an Indian commercial cigarette.
Table 4. Inactivation of the major harmful cs-oxidant and nicotine delivery in
cigarette smoke using activated charcoal filter Methodology
Construction of activated charcoal filter
The activated charcoal filter was constructed by placing stipulated amounts of different grain sizes or mixture of grain sizes of activated charcoal in a thin plastic tube, the inside diameter of which was same as the outside diameter of the tobacco portion of the cigarette or the conventional cellulose acetate filter. The plastic tube could be replaced by tubes
manufactured of light grade materials, namely hard paper tube, plastic wrapped paper tube or tube made with aluminium foil. At the one end of the tube containing the charcoal was inserted the conventional cellulose acetate filter (approximately 10 - 14 mm) which constitutes the mouthpiece and at the other end was inserted the tobacco portion of the cigarette (approximately 63 mm). A thin section of cellulose acetate filter (approximately 3 mm) was placed in the cavity in between the tobacco portion and charcoal bed as depicted in the drawing (Fig. 1). Essentially, the charcoal filter is a cavity filter where the activated charcoal granules are placed in a void space between two segments of cellulose acetate filters. As mentioned above, one portion of the cellulose acetate filter (l0 - 14 mm) is the mouthpiece and other portion (3 mm) constitutes a barrier between the charcoal bed and the tobacco portion (Fig. 1). The portions, namely, the cellulose acetate mouth piece, the charcoal filter, the thin cellulose acetate filter placed in between the charcoal and the tobacco portion and the tobacco portion all are constructed into one single unit (Fig. 1). The cellulose acetate filter does not necessarily improve the filtration of p-BSQ of the smoke. However, its use in cooperation with the charcoal filter adds to the convenience of using it as a mouthpiece for suction. The thin section of the cellulose acetate filter placed in between the charcoal and the tobacco portion was used to prevent any infiltration of charcoal granules into the tobacco of the cigarette. The length of the charcoal packed in the filter corresponded approximately to the weight of the charcoal used. The weight to length proportion was usually 100 mg charcoal corresponding to 5 mm, 200 mg charcoal, 20 mm and so on. The total length of a charcoal filter cigarette using 300 mg of charcoal is 91 mm [10 mm cellulose acetate filter as a mouthpiece, 15 mm charcoal bed, 3 mm cellulose acetate as a partition between charcoal bed and tobacco portion and 63 mm tobacco portion]. The length of the cellulose acetate may be varied, because it is practically ineffective in reducing p-BSQ of the smoke. The grain size of charcoal used has been expressed in the British Standard (BS) mesh. The size BS 25/44 means particles passing through mesh 25 but retained on mesh 44. Similarly, BS 44/25 means particles passing through mesh 44 but retained on mesh 52. All other grain sizes used in this invention, namely BS 52/60, 60/72 and 72/85 are explained in the same way. The length of the charcoal filter can be varied up to 35 mm, length of conventional filter i.e. cellulose acetate filter can be up to 13 mm for cigarette tobacco length of about 63 mm. (Table 4)
Measurement of p-benzosemiquinone (p-BSQ)
p-BSQ was quantitatively measured by HPLC as described before (5). Five to ten micro
liters of the filtered smoke solution was diluted with mobile phase and 20 µl of this diluted
solution was injected to the HPLC column with the UV detector set at 294 nm. The
parameters used are as follows.
Instrument : Simadzu l0A
Column : Silica column (Lichrospher ® Si60, Merck)
Mobile phase : Methylene chloride : methanol (90 : 10, v/v)
Flow rate : 0.5 ml / min
Pressure 29Kgf/cm2
Retention time : 8.808
The amount of p-BSQ present in the smoke solution was calculated from the peak area,
taking 100 ng of p-BSQ corresponding to an arbitrary area of 1,90,000 obtained from a
standard curve.
The efficacy of activated charcoal filters was also determined by measuring the
comparative yields of p-BSQ. p-BSQ was isolated from cigarette smoke solution by
fractional solvent extraction followed by band TLC as described before (5). After proper
dilution of the TLC band extract with the mobile phase, 20µl of the diluted solution was
injected to the HPLC column. p-BSQ was detected at 288 nm, which is the Xmax of p-
BSQ in the mobile phase used. The parameters used are as follows.
Instrument : Simadzu l0A
Column : Lichrospher ® 100 RP-18 endcapped (5µm), Merck
Mobile phase : Water : methanol (95 : 5, v /v)
Flow rate : 0.5 ml / min
Pressure : 38Kgf/cm2
Retention time : 7.242 min
Measurement of oxidative damage of proteins
Protein oxidation as evidenced by carbonyl formation was measured by reaction with 2,4-
dinitrophenyl hydrazine similar to that done before in our laboratory (4). When BSA was
used, the values were expressed as nmoles of carbonyl formed per mg BSA. The
incubation system contained 1 mg BSA and 50 µ1 of smoke solution obtained from
cigarettes with or without charcoal filter in a final volume of 200 µl of 50mM potassium phosphate buffer, pH 7.4. After incubation for 1 hr. at 37°C, the protein was precipitated with 200 111 of trichloroacetic acid solution and the rest of the procedure followed as before (4). Oxidative damage of proteins was also measured by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of guinea lung microsomal proteins as described before (4). Preparation of microsomes
Guinea pig lung microsomes, washed free of ascorbic acid, were prepared as described before (4).
Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) SDS-PAGE of microsomal proteins was performed by the procedures similar to that described before (4). Measurement of nicotine
Smoke from a lit cigarette was allowed to dissolve in 2 ml of 50mM potassium phosphate buffer, pH 7.4 and filtered through 0.45 µm Millipore filter as described before (5). One milliliter of the yellow coloured filtrate was extracted with one milliliter of methylene chloride by vigorous vortexing to extract the nicotine in the methylene chloride layer. Five hundred microliter of the methylene chloride layer containing the nicotine was then vortexed with 500 µl of 50 mM HCl solution and the nicotine of the HCl solution was estimated by HPLC analysis at 254 nm. Five to 10 µl of the nicotine solution was diluted to 200 µl with the mobile phase and 20 µlof this diluted solution was injected to the HPLC column. A standard solution of nicotine was prepared in a similar way and analyzed. The parameters used are:
Instrument : Shimadzu l0A
Column : Lichrospher® 100 RP-18 endcapped (5 µm), Merck
Mobile phase : 50 mM KH2PO4 solution: accetonitrile : methanol;
(78 : 17 : 5, v/v) containing 1 mM
sodium hepatane sulfonate, pH 5.0
Flow rate : 0.3 ml / min
Pressure : 24Kgf/cm2
Temperature : 250C
Retention time : 4.185 min.
The minimum amount of nicotine that could be detected by the HPLC analysis under the
conditions was 10 ng.
Measurement of tar
Tar was collected by placing a Millipore filter unit between the lit cigarette with or without
charcoal filter and the tube connected to a vacuum pump (LKB, Sweden) using a suction of
30cm water. The Millipore filter (0.22 µm) was changed every two minutes to avoid
clogging of the filter. For each cigarette, 4 filters were used. After complete burning of the
tobacco, the filters were dried in a vacuum desiccator and weighed. The difference in
weight of the filters before and after collecting the particulate portion was the weight of the
tar.
Measurement of nitric oxide in cigarette smoke solution
Ten milliliter of air saturated 50-mM potassium phosphate buffer, pH 7.4 was taken in a 50
ml boiling tube with a side arm and a stopper with a hole. An Indian commercial cigarette
was mounted in a tube that penetrated the hole in the stopper and dipped down in the
buffer solution. The side arm was connected to a water pump. The cigarette was lit and the
smoke from the whole cigarette was bubbled through the buffer solution by applying a
suction of 4 cm water. A portion of the cigarette smoke solution thus produced was filtered
through a 0.45 µm Millipore filter and extracted thrice with equal volume of methylene
chloride. The concentration of potassium nitrite in the aqueous layer was measured after
proper dilution by diazotization using Griess regent. A standard solution of NaNO2 was run
side by side.
Exposure of guinea pigs to cigarette smoke
The exposure of the animals to cigarette smoke was done according to a procedure
standardized in our laboratory (19). The guinea pigs were grouped as follows:
Group 1: Control guinea pigs
Group 2: Guinea pigs subjected to smoke from cigarettes without charcoal filter
Group 3: Guinea pigs subjected to smoke from cigarettes equipped with activated charcoal
filter containing a mixture of 0.1 g of BS 52/60 and 0.lg of BS 60/72.
The animals were exposed to cigarette smoke from five cigarettes /animal/day for seven
days following the procedure published before (19). The animals were fasted overnight,

sacrificed on the eighth day, tissue excised, microsomes prepared and subsequently subjected to SDS-PAGE as described earlier (19).
Results
Effects of charcoal filters on the p-BSQ, tar and nicotine contents of the mainstream
smoke as well as inhibition of protein oxidation
Using charcoal filter comprising stipulated amounts of different grain sizes or mixture of grain sizes of activated charcoal, the p-BSQ contents of the mainstream smoke are markedly reduced (Table 1). We have indicated before (5) that among all the compounds present in the smoke solution, only p-BSQ is singly responsible for protein oxidation. Fig. 2 shows that oxidation of BSA, as evidenced by carbonyl formation, is almost quantitatively correlated with the contents of p-BSQ present in the incubation medium. As would be expected, reduction of p-BSQ content in the smoke by the use of charcoal filter is accompanied by marked inhibition of BSA oxidation (Table 1). Use of charcoal filter also results in reduction of some tar and nicotine (Table 1). The most effective grain sizes of activated charcoal, expressed in British Standard (BS) mesh, are 44/52, 52/60, 60/72 and 72/85 used singly or in combination. Grain sizes larger than 44/52, namely 25/44 and 10/25 are not efficient even when used in comparatively large amounts. Use of large amounts of charcoal (0.4 g to 1.0 g) causes problem in suction of the smoke. Use of coconut shell activated charcoal did not have any added advantage over commercially available activated charcoal. The most effective charcoal filters, those markedly reduce p-BSQ content in the smoke without significantly affecting the suction and providing comfortable mouthful of smoke, as evidenced by a panel of middle aged smokers, are given in the Table 1. The charcoal filters comprise 0.2 and 0.3 g of BS 44/52, 0.2 and 0.3 g of BS 52/60, 0.15 and 0.2 g of BS 60/72, 0.1 and 0.15 g of BS 72/85, a mixture of 0.2 g of BS 44/52 and 0.1 g of BS 52/60, a mixture of 0.2 g of BS 44/52 and 0.1 g of BS 60/72, a mixture of 0.1 g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.2g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.15 g of BS 44/52 and 0.1 g of BS 72/85, a mixture of 0.1 g of BS 52/60 and 0.1 g of BS 60/72, a mixture of 0.1 g of BS 52/60 and 0.1 g of 72/85, and a mixture of 0.1 g of BS 60/72 and 0.1 g of BS 72/85, a mixture of 0.1 g of BS 52/60 and 0.05 g of BS 72/85, and a mixture of 0.1 g of BS 60/72 and 0.05 g of BS 72/85.. With the
said charcoal filters, reduction of p-BSQ was in the range of 55 to 85 percent, with a corresponding inhibition of BSA oxidation was in the range of 55 to 82 percent. Effect of fortification of tobacco of the charcoal filter cigarettes with nicotine on the p-BSQ, tar and nicotine delivery of the smoke from an Indian commercial cigarette
Table 1 shows that the charcoal filter cigarettes mentioned in this invention are very effective for markedly reducing the content of p-BSQ, the major hazardous oxidant present in the mainstream smoke. Table 1 further shows that the tar and nicotine delivery of these charcoal filter cigarettes are also considerably reduced. These charcoal filter cigarettes may therefore be considered as potentially safer mild cigarette. Apprehending that there might be some committed smokers who would not like mild cigarette with low nicotine delivery, the tobacco of some of the charcoal filter cigarettes has been fortified with 2 mg nicotine per cigarette and the results are given in Table 2. The results indicate that fortification of tobacco with 2 mg nicotine per cigarette lead to increase the nicotine delivery of the smoke considerably. The increase in nicotine delivery is accompanied by increase in tar content (Table 2). Fortification of tobacco with 3-4 mg nicotine produces about 30 - 50 percent more nicotine delivery (results not shown). However, fortification of tobacco with nicotine does not lead to any increase of p-BSQ content of the smoke, apparently because nicotine is not a precursor of p-BSQ and it does not contribute to either the level of p-BSQ in smoke or oxidation of BSA by the smoke solution (Table 2). The results would indicate that although fortification of tobacco with nicotine of the charcoal filter cigarettes results in increased nicotine delivery, but the said charcoal filter cigarettes remain potentially safer cigarettes.
Effects of charcoal filters on the nitric oxide level in the smoke solution from an Indian commercial cigarette
Nitric oxide (NO) is one of the most important free radicals in the gas phase of cigarette smoke. Some scientists think that NO may be implicated in the development of chronic obstructive pulmonary disease and emphysema in the smokers. Results presented in Table 3 indicates that activated charcoal filter is very effective in reducing the NO level in the mainstream smoke. Using a mixture 0.2 g of BS 44/52 and 0.1 g of BS 72/85, the percent inhibition in the NO is as high as 68.
Protective effect of charcoal filters on the cigarette smoke induced oxidative degradation of guinea pig lung microsomal proteins in vitro
Fig. 3 (lane 2) shows that cigarette smoke solution obtained from an Indian commercial cigarette causes extensive damage of guinea pig lung microsomal proteins as evidenced by SDS-PAGE. The figure further shows that the oxidative damage of microsomal proteins is markedly reduced when the said cigarette was equipped with activated charcoal filters, namely, BS 52/60, 0.3 g (lane 3); a mixture of BS 44/52, 0.2g and BS 72/85, O.lg (lane 4); a mixture of BS 60/72, O.lg and BS 72/85, O.lg (lane 5).
Protective effect of charcoal filter on the cigarette smoke induced oxidative damage of guinea pig lung microsomal proteins in vivo
Fig 4 (lane 2) shows that after exposure of the guinea pigs to cigarette smoke, lung microsomal proteins are discemibly damaged, as evidenced by SDS-PAGE. The oxidative damage is significantly protected when the animals are exposed to smoke from cigarettes equipped with activated charcoal filter containing a mixture of O.lg of BS 52/60 and O.lg of BS 60/72.
Table 1 p-6enzosemiquinone (p-BSQ), BSA oxidation, nicotine delivery and tar contents in the smoke solution from an Indian commercial cigarette with stipulated amounts of different grain sizes of activated charcoal

(Table Removed)
a, British standard b, BS 44/52 means particles passing through mesh 44, but retained on mesh 52. All other grain sizes mentioned in the Table are explained in the same way. c, Indicates mixture of the two grain sizes d, Amount of carbonyl formed by 50 µl of smoke solution. Details of the incubation system and measurement of carbonyl are given under Methodology Section.
Table 2. Effect of fortification of tobacco of the charcoal filter cigarettes with nicotine on the p-BSQ, tar and nicotine delivery in the smoke solution from an Indian commercial cigarette
(Table Removed)
* Values are means of four determinations; SD + Fortification of the tobacco with 3 mg nicotine instead of 2 mg nicotine results in about
30 percent more delivery of nicotine in the smoke (results not shown)
Table 3. Effects of charcoal filters on the nitric oxide level in the smoke solution from an Indian commercial cigarette

(Table Removed)
Table 4. Inactivation of the major harmful cs-oxidant and nicotine deliverv in cigarette smoke using activated charcoal filter

(Table Removed)
* Internal diameter of the charcoal filter was 8 mm.
** The percentage was calculated taking nicotine delivered (940 µg + 40 S.D; n=6) from
cigarette with conventional filter as 100
# BS 44 indicates BS 25 (-) to BS 44 (+), particle size of 350 - 700 µm
# BS 52 indicates BS 44 (-) to BS 52 (+), particle size of 250 - 350 µm
0 26 ram BS 44 + 9 mm BS 52
♦ The lengths of the conventional filters have been depicted in Figs. 36 and 37.
References
1 http://www.tobaccoreporter.com/backissues/Dec2000/Dec2000 feature 2.asp
2 Denissenko, M.F., Pao, A., Tang, M.S. and Pfeifer, G.P. Science 274,430-432 (1996)
3 Hecht, S.S., Spratt, T.E and Trushin, N. Carcinogenesis 9, 161-165 (1988)

4 Panda, K., Chattopadhyay, R., Ghosh, M.K., Chattopadhyay, D.J. and Chatterjee, LB., Free Radic. Biol. Med. 27. 1064-1079 (1999)
5 Chatterjee, I.B., Indian Patent Application No 701/DEL/2001
6 Nagata,., Kodama, M. and loki, Y. in Polycyclic Hydrocarbons and Cancer, Gelboin, H.V. and Ts'O, P.O.P. Eds (Academic Press, New York), 1, 247 (1978)
7 Pryor, W.A., Environ. Health Perspect 105. Suppl. 4, 1, (1997)
8 Church, D.F. and Pryor, W.A. Environ. Health Perspect. 64, 11 1-126 (1985)
9 http://www.law. Indiana, edu/ ilj/ v73/ no 3/ givelber.html
10 Stavridis et. al. US Patent NO. 5,909,736, June 8,(1999)
11 Osaga et. al. US Patent NO.4,038,992, August 2,(1977)
12 Innacelli, US Patent NO. 4,373,539, February 15, 1983
13 WO Patent No. 9600019
14 US Patent No. 5360023
15 US Patent No. 3658069
16 http://www. starscientific.com/066745321909/advancefilter.html
17 http: //www.ryomagazine. com/october/filters .htm
18 www.baumgartnerinc.com/whatsnew.htm
19 Panda, K., Chattopadhyay, R., Chattopadhyay, D.J. and Chatterjee, I.B., Free Radic. Biol. Med. 29, 115 - 124 (2000)

We Claim:
1. A filter for a tobacco smoke inhaling/generating/producing device, the filter having three sections placed longitudinally one after another, comprising: a first section comprising cellulose acetate fiber acting as a mouth piece; a second section comprising requisite amounts of specific mesh sizes of activated charcoal selected from the group consisting of charcoal particles having mesh sizes of BS 44/52, BS 52/60, BS 60/72, BS 72/85, and any combinations thereof for effectively reducing p-benzosemiquinone, a highly reactive major harmful oxidant from the mainstream of said tobacco smoke; and a third section comprising cellulose acetate fiber located closer to a tobacco portion, also acting as a barrier between the activated charcoal and tobacco portion, wherein the activated charcoal is selected from the group consisting of 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 52/60, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.2 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.15 g of mesh size BS 44/52 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 60/72, 0.1 g of mesh size BS 52/60 and 0.1 g of mesh size BS 72/85, 0.1 g of mesh size BS 60/72 and 0.1 g of mesh size BS 72/85,0.1 g of mesh size BS 52/60 and 0.05 g of mesh size BS 72/85, and 0.1 g of mesh size BS 60/72 and 0.05 g of mesh size BS 72/85, and any combinations thereof.
2. A filter as claimed in claim 1, wherein the length of the first section is in the range of 10 to 14 mm.
3. A filter as claimed in claim 1, wherein the length of the second section is dependent on the mesh size and/or amount of charcoal used.
4. A filter as claimed in claim 1, wherein the length of the second section is in the range of 4.5 mm to 35 mm.
5. A filter as claimed in claim 1, wherein the length of the third section is in the range of 2 to 3 mm.
6. A filter as claimed in claim 1, wherein all the three sections are linearly joined together in succession using a thin wall tube made of lightweight material selected

from the group consisting of thin wall plastic tube, paper, plastic wrapped paper and aluminum foil.
7. A filter as claimed in claim 1, wherein requisite amounts of specific mesh sizes of the activated charcoal ranging between BS 44/52 and BS 72/85 mesh are placed in a void space between the sections of cellulose acetate filters namely the mouthpiece and the barrier.
8. A filter as claimed in claim 1, wherein the amount of charcoal used is in the range
between 0.1 g and 0.3 g.
9. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.3 g of the mesh size BS 44/52.
10. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.2 g of the mesh size BS 52/60.
11. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.3 g of the mesh size BS 52/60.
12. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.15 g of the mesh size BS 60/72.
13. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.2 g of the mesh size BS 60/72.

14. A filter as claimed in claim 1, wherein the activated charcoal particle comprises 0.15 g of the mesh size BS 72/85.
15. A filter as claimed in claim 1, wherein said filter is used in smoking devices selected from group consisting of cigarettes, cigarette holders, pipes and any other smoking devices.
16. A filter for a tobacco smoke inhaling/generating/producing device substantially as herein described with the references to the examples accompanying the specification.

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Patent Number

268814

Indian Patent Application Number

1025/DEL/2001

PG Journal Number

39/2015

Publication Date

25-Sep-2015

Grant Date

17-Sep-2015

Date of Filing

04-Oct-2001

Name of Patentee

NATIONAL RESEARCH DEVELOPMENT CORPORATION

Applicant Address

20-22 ZAMROODPUR COMMUNITY CENTRE, KAILASH COLONY EXTENSION NEW DELHI-110048

Inventors:

#	Inventor's Name	Inventor's Address
1	INDU BHUSAN CHATTERJEE	DR. B.C. GUHA CENTRAL FOR GENETIC ENGINEERING AND BIOTECHNOLOGY CULCUTTA UNIVERSITY COLLEGE OF SCIENCE,35, BALLYGUNGE CIRCULOR ROAD, KOLKATA 700019,INDIA.

PCT International Classification Number

A24D3/04

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA