1、BRITISH STANDARD BS 5202-9: 1992 ISO 3401:1991 Methods for Chemical analysis of tobacco and tobacco products Part 9: Determination of alkaloid retention by filters of cigarettes (spectrometric method)BS5202-9:1992 This British Standard, having been prepared under the directionof the Agriculture and
2、Food Standards Policy Committee,waspublished underthe authorityof the Standards Boardand comes intoeffect on 31March 1992 BSI 10-1999 First published July 1977 Second edition March 1992 The following BSI references relate to the work on this standard: Committee reference AFC/11 Draft for comment 88/
3、56193 DC ISBN 0 580 20626 2 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Agriculture and Food Standards Policy Committee (AFC/-) to Technical Committee AFC/11, upon which the following bodies were represented: Department of Trade and
4、Industry (Laboratory of the Government Chemist) Tobacco Advisory Council Amendments issued since publication Amd. No. Date CommentsBS5202-9:1992 BSI 10-1999 i Contents Page Committees responsible Inside front cover National foreword ii 1 Scope 1 2 Normative references 1 3 Definition 1 4 Principle 2
5、5 Reagents 2 6 Apparatus 2 7 Sampling 2 8 Procedure 6 9 Calculation and expression of results 7 10 Test report 7 Figure 1 Example of apparatus currently in use 3 Figure 2 Example of apparatus currently in use 4 Figure 3 Example of apparatus currently in use 5 Publication(s) referred to Inside back c
6、overBS5202-9:1992 ii BSI 10-1999 National foreword This Part of BS 5202 has been prepared under the direction of the Agriculture andFood Standards Policy Committee. It is identical with ISO 3401:1991 “Cigarettes Determination of alkaloid retention by the filters Spectrometric method” published by th
7、e International Organization for Standardization (ISO), and in the preparation of which the UK played a full part. This revision supersedes BS 5202-9:1977, which is withdrawn and from which it differs in that more details of the procedure have been given and the text has been clarified. Additional i
8、nformation. With reference to clause 5, water complying with grade 3 of BS 3978 “Specification for water for laboratory use” is suitable. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct applicatio
9、n. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references International Standard Corresponding British Standard ISO 3308:1991 BS 5668 Routine analytical cigarette smoking machine Part 1:1992 Specification and standard conditions (Identical) ISO
10、 3400:1989 BS 5202 Methods for chemical analysis of tobacco and tobacco products Part 7:1990 Determination of alkaloids in smoke condensate of cigarettes (spectrometric method) (Identical) ISO 3402:1991 BS 5743:1991 Specification for atmosphere for conditioning and testing tobacco and tobacco produc
11、ts (Identical) ISO 4387:1991 BS 5202 Methods for chemical analysis of tobacco and tobacco products Part 14:1992 Determination of total and nicotine-free dry particulate matter using a routine analytical cigarette smoking machine (Identical) ISO 8243:1991 BS 6245 Sampling tobacco and tobacco products
12、 Part 3:1992 Methods of sampling cigarettes (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. Thi
13、s will be indicated in the amendment table on the inside front cover.BS5202-9:1992 BSI 10-1999 1 1 Scope This International Standard specifies two methods for the spectrometric determination of alkaloid retention by filters of cigarettes: the direct method; the indirect method. The methods are appli
14、cable to filter cigarettes. The direct method shall be used unless it is not applicable owing to incomplete recovery of the retained alkaloids from the filter material (for example, with some types of charcoal filters). The indirect method is not applicable to cigarettes with perforated or porous fi
15、lter tipping wraps. This International Standard is not applicable in the case of filters having an irreversible nicotine retention and equipped with perforated or porous wrapping. NOTE 1These methods determine the retention only of alkaloids of tobacco smoke, expressed as nicotine. The retention of
16、other substances present in the mainstream smoke is not necessarily related to the alkaloid retention. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editio
17、ns indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently v
18、alid International Standards. ISO 3308:1991, Routine analytical cigarette-smoking machine Definitions and standard conditions. ISO 3400:1989, Cigarettes Determination of alkaloids in smoke condensates Spectrometric method. ISO 3402:1991, Tobacco and tobacco products Atmosphere for conditioning and t
19、esting. ISO 4387:1991, Cigarettes Determination of total and nicotine-free dry particulate matter using a routine analytical smoking machine. ISO 8243:1991, Cigarettes Sampling. 3 Definition For the purposes of this International Standard, the following definition applies. 3.1 alkaloid retention ind
20、ex R nicof a cigarette filter the ratio, expressed as a percentage by mass, of the alkaloids retained by the filter to those entering the filter: The alkaloid retention index may be determined as follows: a) Directly, by measurement of the mass of alkaloids retained by the filter and of the mass of
21、alkaloids in the mainstream smoke leaving the filter: where b) Indirectly, by measurement of the difference between the mass of alkaloids contained in the mainstream smoke from a cigarette with filter (A) and of the corresponding mass from another cigarette with filter material removed (B), the smok
22、ed length of which is the same as that of the filter cigarette (A): where F nic is the mass of alkaloids retained by the filter; H nic is the mass of alkaloids in the mainstream smoke leaving the filter; S nic is the mass of alkaloids entering the filter see (A) above. H nic the mass of alkaloids in
23、 the mainstream smoke from the cigarette with filter (A); S nic is the mass of alkaloids in the mainstream smoke from the cigarette with the filter material removed (B).BS5202-9:1992 2 BSI 10-1999 4 Principle 4.1 Direct method Smoking of the filter cigarettes (A), in accordance with ISO 4387 on a ro
24、utine analytical cigarette-smoking machine complying with the requirements of ISO 3308, and removal of the filter tips from the cigarette butts remaining; subjection of the filter tips, after addition of methanol, to steam distillation from acid solution to remove neutral and acid steam-volatile sub
25、stances, and discarding of the distillate. Rendering of the residue in the distillation chamber alkaline by addition of alkali, and steam distillation of the alkaloids; estimation of the alkaloid content by spectrometric measurement of the absorbance of the distillate from the alkaline distillation,
26、 and calculation of the alkaloid content as nicotine. Collection of the mainstream smoke condensate from the filter cigarettes (A), preparation of a methanolic solution of the condensate and determination of its alkaloid content by distillation in accordance with ISO 3400. 4.2 Indirect method 4.2.1
27、Smoking of the filter cigarettes (A) in accordance with ISO 4387 on a routine analytical cigarette-smoking machine complying with the requirements of ISO 3308, collection of the mainstream smoke condensate, preparation of a methanolic solution of the condensate and determination of its alkaloid cont
28、ent by distillation in accordance with ISO 3400. 4.2.2 Removal of the filter material from a second sample of identical filter cigarettes (A), smoking of the remaining tobacco rods (B) in accordance with ISO 4387 on a routine analytical cigarette-smoking machine complying with the requirements of IS
29、O3308, collection of the mainstream smoke condensate, preparation of a methanolic solution of the condensate and determination of its alkaloid content by distillation in accordance with ISO 3400. 5 Reagents Use only reagents of recognized analytical grade and distilled water or water of at least equ
30、ivalent purity. 5.1 Methanol 5.2 Sodium hydroxide, solution, c(NaOH) = 8 mol/l. 5.3 Sulfuric acid, solution, c(H 2 SO 4 )= 1 mol/l. 5.4 Sulfuric acid, solution, c(H 2 SO 4 ) = 0,025 mol/l. 5.5 Nicotine, minimum purity 98 %. 6 Apparatus Usual laboratory apparatus and the following items: 6.1 Conditio
31、ning enclosure, regulated in accordance with the requirements of ISO 3402. 6.2 Routine analytical cigarette-smoking machine, complying with the requirements of ISO 3308, with glass fibre filter smoke trap (see ISO 4387). 6.3 Steam distillation apparatus, consisting of the following parts: 6.3.1 Dist
32、illation chamber A cylindrical, vertically mounted distillation chamber of about 50 ml to 100 ml capacity, which has a steam inlet at its base. It shall be possible to heat the chamber in order to maintain a constant liquid level during the distillation. 6.3.2 Distillation splash head 6.3.3 Jacketed
33、 coil condenser, with spherical joint fitting on to the distillation splash head (6.3.2). 6.3.4 Plug-type funnel, or other system for addition of sodium hydroxide solution and, if required, the filter tips. 6.3.5 Testing of the distillation apparatus Test the system in accordance with the indicated
34、procedure (ISO 3400) with pure nicotine solution(5.5) at the maximum expected level. Recovery shall be at least 98 % of the theoretical value. If not, optimize by modification of the distillation rate. For routine tests it is possible to use nicotine salt calibrated against pure nicotine(5.5). NOTE
35、2The diagrams of apparatus currently used (Figure 1 to Figure 3) are given as examples. Other apparatus may also be used provided that the results obtained are the same. 6.4 Spectrometer, covering a wavelength range from230 nm to 290 nm. 6.5 Quartz cells, having an optical path length of1cm, or iden
36、tical matched cells in the case of a single beam apparatus. The absorbance of the cells shall be equal before and after each measurement; if not, a suitable correction shall be applied. 6.6 Volumetric flasks, of capacity 250 ml, with ground stoppers. 6.7 One-mark pipettes, of capacities 5 ml, 10 ml
37、or25ml. 6.8 Glass funnels, of diameter about 55 mm. 6.9 Filter paper, fast filtering grade. 7 Sampling Carry out sampling in accordance with the method specified in ISO 8243.BS5202-9:1992 BSI 10-1999 3 NOTE 1All glass is medium wall borosilicate. NOTE 2Stopcocks: 4 mm bore PTFE. Figure 1 Example of
38、apparatus currently in useBS5202-9:1992 4 BSI 10-1999 Figure 2 Example of apparatus currently in useBS5202-9:1992 BSI 10-1999 5 NOTEAll glass is medium wall borosilicate. Figure 3 Example of apparatus currently in useBS5202-9:1992 6 BSI 10-1999 8 Procedure 8.1 Direct method 8.1.1 Preparation of test
39、 sample Select from the laboratory sample prepared in accordance with clause 7 the required number of filter cigarettes for the set of smoking runs to be carried out and condition them in accordance with ISO 3402 in the conditioning enclosure (6.1). 8.1.2 Determination 8.1.2.1 Smoking Smoke the cond
40、itioned cigarettes (8.1.1) in accordance with ISO 4387 on the routine analytical cigarette-smoking machine (6.2) in one or more smoking processes. Collect the mainstream smoke condensate in the appropriate trap for each smoking process. As soon as each cigarette has been smoked to the required butt
41、length, extinguish it. At the end of each smoking process remove the filter tips and the traps. Proceed to 8.1.2.2 and 8.1.2.3 without delay at any stage. 8.1.2.2 Determination of alkaloids retained in the cigarette filters (F nic ) Carefully remove any adhering tobacco from the filter tips and cut
42、them open. Open the still and place a maximum of three tips in the distillation chamber. Close the still and introduce about 10 ml of the methanol (5.1) into the chamber. NOTE 3A less desirable alternative to placing the tips directly into the distillation chamber is to use a methanolic extract, as
43、follows: Place 20 tips and 100 ml of methanol in a flask. Shake it for 30 min or allow it to stand overnight and shake by hand. Using a pipette, transfer 10 ml of extract to the distillation chamber. WARNING Take care during the distillation while sodium hydroxide is being added. Add 10 ml of the su
44、lfuric acid solution (5.3) and start the distillation. Collect about 100 ml of the distillate in a beaker. Without stopping the distillation, remove the beaker and discard the distillate. Insertthe delivery tube into a 250 ml volumetric flask (6.6) containing 10 ml of the sulfuric acid solution (5.3
45、). Ensure that the end of the tube isimmersed in the acid. Slowly and carefully add5ml of the sodium hydroxide solution (5.2) to the distillation chamber, closing the inlet funnel(6.3.4) as the last drops pass through. Collect220 ml to 230 ml of distillate. Remove the flask whilst rinsing the delive
46、ry tube with a little water. Terminate the distillation and clean the still, using forceps if necessary to remove the filter tips. Ensure that the flask is at room temperature, dilute the distillate to the mark with water and mix. Ifthesolution is not clear, filter through a filter paper (6.9), disc
47、arding the first 150 ml of filtrate. Use the solution to determine spectrometrically the alkaloids retained in the cigarette filters, in accordance with ISO 3400. 8.1.2.3 Determination of alkaloids in the mainstream smoke condensate (H nic ) Having removed the traps containing the mainstream smoke c
48、ondensate from the filter cigarettes smoked, proceed according to the following method: Dismantle the holder and remove any sealing ring with forceps. Remove the disc with forceps and fold twice. Place the folded disc in a conical flask of capacity 150 ml containing a suitable volume of methanol (5.
49、1). The volume shall be adjusted according to the number of traps and cigarettes smoked so that the alkaloids from two to three cigarettes are contained in the aliquot of methanolic solution taken for the distillation (ideally 20 ml). Wipe the inner surface of the holder front with two quarters of a blank filter disc held with forceps, and put these into the flask. Close the flask and shake onan electrical shaker for 20 min or let it stand for16 h ensuring that the disc does not disintegrate. Use, as the test portion, an aliquot of this s
