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-6- This wag as expected as the addition of most burn additives at normal levels of addition to cigarette papers tend to produce an increase in the cigarette burn rate. This is reflected by both the 12NC and 12-4GACO static burn rate value as a function of additive level as indicated in Table 3. However, it has previously been identified (9) that as the burn additive level is increased, on a given base paper, the burn rate will increase until reaching a maximum value at a certain additive level. After this point, the burn rate will decrease with furzher burn additive aGdition. A plot of cigarette puff number versus potassium tartrate level for 12NC, 12-4GACO and 12-4C10 papers is shown in Figure I. It can be seen from this graphical plot, that cigarettes made with 12NC and 12-4GACO papers show the expected trend of decreasing puff number with additive level, whereas the 12-4C1g sample is largely uninfluenced by the level of potassium tartrate. The relative]y constant puff number with the L2-4CI0 sample is due to the paper already having a high level of burn additive addition in the form of 9.1% tri-potassium citrate and this loading of citrate is sufficient for the burn rate to start decreasing when additional burn additive is applied. A plot of mainstream carbon monoxide v~rsus additive level is shown in Figure 2a in % v/v terms. With the 12NC cigarette paper, an increase in potassium tartrate level gave a clear increase the mainstream earoon monoxide in percentage volume/ volume terms from this cigarette, However, gO in mg/cig from the cigarette (Figure 2b), showed a slight decrease and then a slight increase with increasing potassium Lartrate additio~l level to the cigarette paper. This apparent modification in the change in the trend of CO with additive level is because the puff number of the cigarette decreases rapidly (i.e. i~creases burn rate)~ with the initial addition of low levels ~f potassium tartrate to the cigarette paper (Figure i), and then shows less of a decrease in puff ~umber as the level ~f aeditive is further increased. 570365161

-7- The 12-4CI0 shows an increase in CO in both volume/voluble and mg/eig terms from the cigarettes with increasing potassium tartrate level on the paper. This is as expected because of the slight increase in puff number with the 12-4CI0 paper with increasing potassium tartrate addition level. The 12- 4GACO shows an increase in CO % volume/volume from the cigarette with increasing potassium tartrate level on the paper. This. when combined with the effects of a decreasing puff number, gives a reduction in CO in mg/cig with increasing potassium tartrate level. Therefore, the addition of potassium tartrate to a pager containing magnesium hydruxide provides reductions in the mainstream deliveries of CO from the cigarette. A plot of cigarette mainstream particulate matter, water and nicotine free. (PMWWF) and total nicotine alkaloids (TNA) versus additive level on the cigarette paper is shown in Figures 3a and 3b respectively. These figures show that both cigarette TNA and PMWNF tend to decrease with increasing potassium tartrate level on the 12NC and 12-4GAC0 papers. This would be expected from the effect potassium tartrate level on puff number (Figure ]), i.e. as the puff number is decreased, the total mainstream delively of the cigarette is reduced. With the IE-4CIO gaper there is little change in TNA and PMWNF with increasing potassium tartrate addition level t~ the cigarette gaper. This was again as expected due to the relatively constant puff number with increasing levels of additive on this paper. Figure 4a shows a plot of the cigarette sidestre&m PMWNF and Figure 4b T~A versus percentage potassium tartrate on the pager. From the glott~d delivery data in Figur~ 4a and 4b. the trends in behaviour fur 12-4SAC~ and 12-4CI0 are not clear. The only paper which shows a consistent trend for both TNA and PMWNF i5 the 12NC cigarette gaper. The 12 NC gapen shows a slight decrease in TNA and PMWNF from the ~igarettes with increasing potassium tantrate addition, With the 12-4GACO cigarett~ paper, the effect on increasing 570365162

-8- level of potassium tartrate on the PMWNF is to give an increasing reduction in emission until appro×imate]y the 3.5% addition level, after which the PMWNF delivery starts to rise again, this is again as expected (9). Huwever, the effect of increasing levels of potassium tartrate on TNA emission follows the opposite trend and accounts for the increased TNA/PMWNF ratio in the sidestream of cigarettes based on the magnesium hydroxide/high level burn additive formulation. The effect of increasing potassium tartra[e level on the TNA and PMWNF emisisons for the 12-4CI0 paper is complex as can be seen from Figure 4. The slope of the curves for the 12-4C10 cigarebte paper may in part be due to the fairly constant cigarette puff number achieved with incrmasing chemical level, but this only gives a partial explanation of the results. The chanye in sidestream TNA to PMWNF ratio, with increasing level of potassium tartrate on the cigarette papers, is shown further in Figure 5. This Figure shows an increasing TNA/PMWNF ratio for cigarettes made with the 12NC cigarette paper, with increasing percentage potassium tartrate addition. Whereas for cigarettes made with both the 12-4GAC0 and 12-4C10, the TNA/PMWNF ratio reaches a maximum with increasing potassium tartrate addition and then ~ecreases with further increase in additive level. This sidestream TNA/PMWNE ratio is important with regard to the subjective response to sidestream irritation (10), and the ability to be able to reduce the sidestrcam TNA/PMWNF ratie by the optimisation of the level of addition of a burn additive could potentially be advantageous. Figure 6 shows a plot of the percentage reduction in sidestream PMWNF versus percentage potassium tar~rate additinn t~ the three Cigarette papers. The percentage reductions in sidestream PMWNF were Calculated using the ei~issions OT the cigarettes made with the appropriate base papers, i.e. the untreated 12-4GACII, 12-4 Clg and 12NC. The percentage reductions would therefore be higher if they were plotted using a cigarette 570365163 ~7 8 A T i L K in~ E ,po~, LLm,~c~ Th,s r~ mu~ n~ b¢ ¢op,ed or ~ho~n ~ ~nlu1~n~.d pcc~o~s

-9- made with a ~onventional paper at a permeability of about 50 C,U.~ as the contr~l value, It can be seen fro~ Figure 6 that there i$ an optimum ]evel of potassium tartrate addition wh?ch will give the maximum PMWNF red~ction for cigarettes made witll a piven paper, ~or the 12-AGACO paper, this addition ]eve] is surprisinply low at abou~ 3.5% w/w, which is much lower than the 5-10% addition levels of tri-potassium citrate ~d s~m a~et~e tha~ we have pre,liously tri~d as ad~itiws on this type of paper (paper containing magnesium hydroxide) with Papeterles de Mauduit (11). The 12NC paper shows the optimum level af ~otassium tartrate ~dd~t~on m~Y be beyond the maximum level applied of 8.1%, Whereas the 12-~CL0 paper has a high level of tri-po~assium citrate ~Iready present on the ciparette paper, Therefore the effect ~f adding the po~sslum tartrate is tO produce a large total ~h~mic~l ~ev~I ~ the ~per, m~ki~g the ~p~im~m I~ ~f addition to the IZ-4CI0 paper very low at about 1.5%. 5.2 Effec~ of Sodium Acetate Addition From Ta~les 3 and 4, the effect o[ sodium acetate a~dit~on to the ¢ig~rett~ paper" on m~in~trea~ and sides~re~l r~sul~$ can ~e e~1~ted, F~r ¢ig~rett~ c~de~ ~3~3, V34A ~ V3~5 sodium acetate was added to the 12oAGAC{], 12-A~l(] and 12NC cigaretbe ~aper$ r~spe~ively. The sodium acetate ~a$ only appl~ed at one level t~ each of the ~hree cigarette paper types. However, it i5 reasonable to make the assumption %hat the s~i~m ~cet~e b~rn ~d~iti~ will f~]]~ th~ s~me general ~rends as ~he ~otas~iunl tartr~te regarding the effect of ~dd~:ive level on smoke ~hara~er~ics, This assumption i~ sup~cted by the ~imi]ari~y found between the ~otas~ium ta~'trate r~s~i~s and the effect of potassium citrat~ addition (~). The main e~fects can be Suiiimari~d as follows for the 1Z-AGACO, 12-4 CLO and 12NC cigarette papers. The ac~dJ~ion of sodi~r~ ac~ate to the cigarette [)~per ~ives an increase iTl ~ff ~ber r~]ativ~ t~ Cigarettes ~ad~ ~ith p~pe~s 570365164 IVH~ B A T ~ K ~ E*p~) Ll~iE(d Thls repo~ mus[ no( b~ ¢~p,ed or ~how~ lo Ln lui~n~ed F~r~on~

-10- containing potassium tartrate. AS would be expected, this is shown ~lso by the static burn rate (SBR) figures i~ mm min-I which are lower for the sodium acetate addibive. The addition of sodium acetate in place of potassium bartrate also gives slightly greater reductions in sidestream TNA values for the cigarette, Whereas the sidestream PM~F emissions are similar for additions to the cigarette paper of both burn additives, there is an increase in the PMWNF and TNA in mainstream with the sodium acetate when compared with the potas~hJm tartrate additive. The increase in PMWNF with the sodium acetate, by calculation of the mean PMWNF values per puff, is very close to the value obbained for the potassium Lartrate. Therefore the increase in PMWNF is pFobably a puff number effect. However, the increase in T~A is approximately 6.5% higher bhan wouid be expected from a puff number ~ffect, Therefore~ the sodium acebat~ is ~ffecting a slightly better m~instream/sidestream partitioning of TNA than the potassium ~artrate. 5.3 Effect of Potassium Lactate Addition A comparison similar to the above can also be made between the potassium bartrate and the potassium l~ctate additives, I~ this case, the effect OF the two burn additives on the three papers are almost identical, apart from a slightly lower SBR and ~ence slightly higher puff number for cigarettes made with papers containing the potassium lactate additive. 5.4 Effect of Magnesium Citrate/Citric Acid Addition From Tables g and 4 (cigarette codes V34B, V350 and V351) the addition of a mixture containing magnesium citrate and citric acid applied to the cigarette paper can be evaluated for its effect o~ the mainstream an~ $idesbream smoke characteristics. This mixture was applied ~% one level to 570365165

-ii- earn of the fol7owing cigarette pagers: 12-4GACO, 12-& CI0 and 12~C. The solutions used for the application of the two additives contained nearly equal quantities of both the magnesium citrate and citric acid on a weight volume basis, the actual amount of the additives present in the cigarette papers after application are shown in Table 2. The effect of addition of citric acid go cigarette paper is described later in this report, hub because ot the lack of solubility of magnesium citrate in water as opposed to citric acid solution, the effect of magnesium citrate addition on its own could not be evaluated, The main effects of the magnesium citrate/citric acid mixture on the mainstream smoke deliveries and sidestream Smoke emissions on cigarettes made witb the three treated cigarette pagers can be suNmarised as follows: The addition of the mixed burn additive gave a decrease in the SBR in mm min"I for cigarettes mado with all three ~ager types when compared to cigarettes made with the base papers (i.e. untreated). This, as expected, gave an increased puff number for the treated samples. AI] the treated samples gave a reduction in sidestream PMWNF, the range of reductions was 10% to 18%, when compared to the untreated samgles, The greatest PMWNF reduction, i,e, the 18%, was obtained from the cigarette with the magnesium citrate/citric acid applied t~ the 12 ~CI0 cigarette paper. The additinn of the mixed additive to the 12-gGACO and 12-4 CIO gapers gives little chang~ in sidestream TNA, when compared with cigarettes made from the base pagers. However, there was a reduction in sidestr~'am TNA when the ISNC pager was used. The reason for thi~ was probably due to the fact that this gaper is a chemical free conventional pagor and therefore the sides~ream TNA is high with cigarettes made with this paper relative to the 12-gGACO an~ 12-4 CI0 gapers. Therefore it is easier to get an imgrovement~ i .e TNA reduction> because 5?03GSIEG

-12- the starting point is the worst situation possible. The mainstream PMWNF and TNA deliveries are little affected by the addition of the magnesium citrate/citric acid to the cigarette paper, apart from slight increases due to increases in the puff number. ~,b Acimic Burn Additives From Tables 3 ana 4 (cigarette codes V352. V353, V354 and V356) the addition of additives which are acidic in aqueous solution can be evaluated. The addizives used were aluminium sulphate, a~onium dihydrogen orthophosphate, potassium hydrogen phosphate and citric acid. The levels of these additives applied are shown in Taole 2. These acidic burn additives were applied to the 3-21 CTTgCU cigarette paper, because of the neutral nature of its titanium dioxide filler, Section 3. Hence, if the pH of the paper can be redcued by the addition of acidic additives, there is a greater probability of the basic componeTltS in the si~eszream smoke becoming trapped on the paper and subsequently burnt to lower molecular weight compounds (12). The indicator of this process occurring with these samples, is a reduction in the sidestream TNA. as nicotine is basic. A reduction in sidestream TNA will gi~e a reduction in the subjective evaluation of the sidestream smoke irritation (ig). 5.5.1 Effect of Aluminium Sulphate Addition A summary of the effect of aluminium sulphate addition, obtained from an evaluation of the cigarettes made with untreated and treated 3-21 CTTBCU cigarette paper, cigarette codes V363 and VBBB, is as follows. ]he aluminium sulphate addition to the cigarette paper resu!ted in an ~pproximately i0% increase in the mainstream PMWBF and TNA delivery ~f the cigarette, which was CauSed by a similar increase in the puff number ~f the cigarette. The addition of aluminium 570365167 19HTBAT dCK anu E,~n~LJmlLed lh~:¢p~nmu~LnoLb~¢npl~dOr~hownleu~ulhon~ed~on~

-13- sulphate to the paper also causes an increase in the mainstream carbon monoxide in mg/cig, in the same order as the increase in puff number. The Carbon monoxide in volume/volume terms being the Same for the treated and untreated cigarettes. Sidestream emission results from the aluminium sulphate treated cigarettes s~owed a g% decrease in TNA, a 9% increase in PMWNF and a]so a slight reduction in carbon monoxide. Therefore, the aluminum sulphate as expected gave a reduction in sidestream TNA and a decrease in the sidestream TNA/PMNNF ratio. 5.5.2 Effect of Ammonium Dih%drogen Ortnophos~hate Addition A summary of the main effects of ammonium dii!ydrogen orthophosphate can be made by evaluation of cigarettes with untreated and treated paper, cigarette co~es V363 and V353, The addition of ammonium dihydrogen orthophosphate tn the cigarette paper caused a 26% increase in the mainstream PMWNF and a 16% increase in the mainstream TNA delivery of the cigarette. This increase in PMWNF and TNA was much greater than could be caused by the very slight increase (2%) in puff number. The treated cigarettes also gave d very large increase in mainstream CO, 67% in mg/cig terms and a 63% increase in % v/v. The addition of the normally used burn additives to cigarette paper, i.e. sodium and potassium citrates, formate and acetates plus some of the phosphates, causes an increase in the mainstream CO delivery in % v/v zerms (13). However, as thes~ burn additives tend to increase the burn rate of the cigarette, there is a self compensating effect and therefore the CO delivery in mg/cig ~erms aoes not increase by very much. Thu~, the large increase in mainstream CO delivery with the cigarette containinS ammonium dihydrogen orthopho~phate in the wrapper is partly due to this previously seen 'chemical effect' coupled with the fact that the burn rate is not increased, but is marginally slower. The addition of the aGllllOrliUlll dillydrog~n orthophospha~e $7036516S 19~AT IUK ~nd E,~,L,m.¢d ]h~ r~mu~noL~ CnpLcdor~ho~nEounaut~n~ ~on~

-14- to the paper gave a 21% reduction in the sidestream TNA emission of the cigarette. A reduction was expected, because of the acidic burn additive paper pH theory already mentioned. The treated cigarette gave a slight increase (= 4%) in the sidestream PMWNF omission and therefore gave a low TNA/PMWNF ratio of 0.17. This sample cigarette also shewed a slight decrease in the sidestream CO mg/cig. 5,5.3 Effect of Potassium Dihydrogen Phosphate Addition The main effects, on the deliveries of cigarettes, of the addition of potassium dihydrogen phosphate to the 3-21 CTTgCU cigarette paper (V354) are as follows. There was a 26% fncrease in the mainstream PMWNF and a 20% increase in the mainstream TNA delivery of the cigarette, The treated sample also gave a slight increase in puff number (3%). These results are very similar to those obtained for the ammonium dihydrogen orthophospha~e described previously, The potassium dihydrogen phosphate treated sample also gave a 37% increase in the mainstream CO delivery in mg/cig terms. The treated sample gave a 26% reduction in sidestream TNA and a 23~ reduction in sidestre~m PMWNF emissions. Therefore, although this sample gives quite a high reduction in sidestream TNA emission, it gives a very small reduction in the TNA/PMWNF ratio, The potassium dihydrogen ghosahate treated sample as with the previous chemical additives, also gave a slight reduction in the sidestream CO emission. 5.5.4 Effect of Citric Acid Addition The last of hhe series of four additives added to the 3-21 CTT9CU paper was citric acid, cigarette code V35E. This additive was apglied to the cigarette paper at a higher level resulting in g.g% w/w on the p~per. The main effects on the smoke results caused by addition of citric acid to 570365i69 (~ ~q~TBAT IUX ,~dEx~x~L,m,1¢~ Thls r¢~mmu~t not bccopicdor ~hown~oLnaulbom~cd pe~on~

15- the 3-21 CTTgCU cigarette paper were as fellows. The citric acid treated sample gave a 12% increase in the mainstream PMWNF and a 10% increase in the mainstream TNA deliveries. This was in the order expected due to a 13% increase in the puff number. The treated cigarettes also gave an 18% increase in the mainstream CO (mg/cig); this was also close to the value exoected. The cigarette with citric acid treated paper gave a 14% reduction in the sidestream TNA and a 10% reduction in the sidestream 9MWNF emissions. Therefore, this cigarette gives only a slight reduction in the sidestream TNA/PMWNF ratio. The addizion of citric acid in common with the other chemicals added to the 3-21 CTTgCU paper also gave a slight decrease in sideszream CO emission. The effect of citric acid addition was also examined for the S5C gaper, cigarette code V355. S5C is a cigarette paper type with a high substance (go g m-21, low chalk inclusion (L5% w/w) and a high level of tri-potassium citrate (I0% w/w). It should be noted also, that the citric acid addition in this case is much lower than the previous example, being only 2.2~. The cigarette with the treated SgC paper gave a !g% increase in mainstream T~A and a 4% increase in PMW~Fi these being similar in magnitude to the 6% increase in guff number, Also the treated cigarette Showed a L3~ increas~ in th~ mainstream CO (m~/cig) delivery. Addition of citric acid t~ the sgc cigarette paper gave an effect on the $idestream Smoke emissions of the cigarette, a 20% reduction in TNA and a 16% reduction in PMWNF. Therefore, the treated sample only gave a small reduction in the TNA/PMWNF ratio. The trea~ed sample also ~ave a small reduction in sidestream CO, as with the previous citric acid sample on the 3-21CTTgCU cigarette paper. 5.6 Effect of Sodium Carbonate Addition fh~ effect of additiorl of sedium carbonate to the 12NC cigarette paper can be summarised as follows, The treated 570365170 I~? B A T L ~ J~d E,~n~ L,m,l~d ThL~ re~x)~ m~L no~ ~¢ c~pled or ~ho~n to ~naol~cfi ~om~