Facsimile Cover Sheet To : Joseph Sherma Company : Department of Chemistry Lafayette College Phone : 610-250-5220 Fax : 610-250-9263 From : Mike Ogden Company : R . J . Reynolds Phone: 910-741-5787 Fax: 910-741-0719 Date : 18-Sept-94 Pages including this cover page : 5 Comments : Dr. Sherma : Following is my complete review of JAOAC Int . Doc #94122 . I am also sending the original via first class mail ; however, it won't leave here until Monday. Again, I apologize for the delay in getting this review to you . Sincerely, Michael W. Ogden, Ph.D . Master Scientist Research & Development http://legacy.library.ucsf.edu/tid/shf01d00/pdf Review of "GC Analysis of Acrolein as 1-Methyl-2-pyrazoline in Mainstream Cigarette Smoke" (Doc #94122) by T . Miyake and T . Shibamoto General Comments I must admit, up front, that my recommendation on this paper is split between Accept After Revision and Reject . I'll elaborate more below but, briefly, the overall dilemma is that the paper contains some good analytical work yet the work has absolutely no relevance to any research areas that the authors discuss . I believe that the analytical work may be worthy of publication, but not in the context of the current manuscript . I see the necessary re-writing on the manuscript as being substantially more than "revision" and, therefore ; recommend : rejection of the manuscript in its present form . Specific Comments p . 3, lines 1-14 - In the introduction, the authors are apparently setting the stage for the utility of the methodology that they eventually describe . Lines 1-3 discuss ambient air quality ; lines 4-8 discuss indoor air quality ; and lines 9-14 describe respiratory system effects in smokers . However, the method described has no obvious utility in any of these areas . Further, the three areas described are not, in any straightforward way, inter-related . For instance (lines 12-14), I fail to see the important connection between acrolein in mainstream smoke and indoor air levels of acrolein . These are two separate issues . The real issue for indoor air quality is the smoke emanating from the other end of the cigarette ; the so-called sidestream smoke . Even more correctly, the issue is the so-called environmental tobacco smoke, that is, the study of the sidestream smoke after it has aged and diluted to room conditions . Even if the mainstream smoke analysis described in this paper were realistic (more on this later), there is no relevance to indoor air quality . p . 4, lines 19-27 - The smoking conditions used to generate "mainstream cigarette smoke" are bizarre . (Novel, but bizarre nonetheless .) _One of the major advances in cigarette smoke testing and research in the last three decades is the adoption of standard smoking conditions by the Federal Trade Commission (FTC) . These conditions are followed closely by government, academic, and tobacco industry laboratories throughout the United States . Similar conditions have been adopted by ISO (the International Standards Organization) for cigarette testing throughout the rest of the world . These conditions describe an exact manner for conditioning and smoking cigarettes . The relevant (FTC) smoking conditions are: take a 35-cc puff of 2sec duration once a minute until a predetermined length of the cigarette has been consumed . The reasons for adopting standard smoking conditions are simple : To enable meaningful comparison of results for different cigarettes among different labs . The smoking conditions described in this paper are extremely unrealistic and have no relevance to the normal smoking, or testing, of cigarettes . Therefore, publication of this paper under the pretense of a method for determining acrolein in mainstream cigarette smoke will most certainly add confusion, http://legacy.library.ucsf.edu/tid/shf01d00/pdf 1 rather than clarification, to the literature . Since a cigarette is normally consumed in short "bursts" of puffing (typically 7-10 puffs) over a period of 7-10 minutes, the rapid consumption of all the tobacco in one continuous 20-sec "puff" will certainly yield vastly different smoke yields than any "normal" smoking . This is seen by comparison of the acrolein values generated in this study and the majority of literature values cited by the authors ; the values in the current manuscript are about an order of magnitude higher . Quite simply, the combustion conditions used here are not equivalent to normal smoking conditions . p . 5, line 2 - How is the removal of sodium sulfate accomplished? p . 5, line 5-12 - The authors are extracting the acrolein derivative in dichloromethane for subsequent determination by GC with a nitrogen-phosphorous (more correctly called a thermionic ionization) detector . However, the manufacturer of the instrument used (HewlettPackard) specifically cautions against the use of chl9rinated solvents with its NPD . What are the long-term implications for method stability and ruggedness when using dichloromethane with H-P's NPD? p . 5, line 17 - What mode of injection was used? Exact operation conditions (split, splitless, valve times, flows, etc.) need to be specified . p. 5, lines 18-20 - The identity of the internal standard should be listed here in the experimental section and not in the results (p . 6, line 17). Also, the statement regarding the internal standard method is incorrect . It is correctly the relationship between the analyte/I .S. weight ratio and the analyte/I .S . GC response ratio . This can be simplified to the relationship between analyte concentration and the analyte/I .S . GC response ratio if the same amount of internal standard is added to samples and standards . It is not simply the relationship between amount of acrolein and GC response, as the authors state . p . 5, line 24 - More details should be given on the "confirmation" by GC-MS . This would best be accomplished by adding a figure that compares an authentic spectrum with a sample spectrum . p. 6, line 7 - How was the "lowest detection level" determined? Is this a simple S/N ratio, or is it the more correct procedure that employs statistical treatment of results from low-level samples/standards/blanks? p . 6, line 14 - The regression equation adds nothing to the manuscript and should be deleted . p . 6, line 23 - I find it very surprising that the size of cigarette did not influence the amount of acrolein determined . To a first approximation, the amount of acrolein determined should be related to the amount of tobacco burned . It would seem likely that the unusual smoking conditions employed in this study would have produced a better fit between cigarette size and amount of acrolein than the standard smoking method since the method described here is likely to minimize differences in burn rate between puffs that would arise due to differences in paper http://legacy.library.ucsf.edu/tid/shf01d00/pdf 2 porosity, tobacco packing density, etc . This result makes me question the accuracy of the determination reported in this paper . Although it would add little to the viability of the currently proposed method, there are two additional experiments I would recommend for further validation . These experiments would also address another limitation of the current method ; there is no indication of the capacity of the proposed collection system for acrolein . In other words, how much acrolein is too much? The additional experiments are as follows . First, investigate the additivity of results for multiple cigarettes (in other words, verify that the acrolein results increase in consistent proportion if 1, 2, and 3 cigarettes are smoked into a single collection vessel) . Second, investigate interference and matrix effects by conducting standard addition experiments . Quantitation by the internal standard and standard addition methods should give equivalent results in the absence of interferences . p. 7, lines 3-4 - Comparison of the results in this stu,dy (p . 6 ; 242 gg/cig average) with the results cited on p . 7 (13-25 µg/cig) shows that the current method yields an order of magnitude higher results . If the quantitation is accurate, this is almost certainly an artifact of the smoking method used . p . 7, lines 6-19 - This discussion, and Figure 2, seems out of place here . Since the authors did nothing to investigate their hypothesis, this is mere speculation on their part . Accordingly, this discussion and the figure should be deleted . Table 1- The listing of results for individual brands seems to be overkill . Since these results cannot be compared to standard conditions employed for testing, there is little to be gained from an itemized listing . One piece of information that could be garnered from Table 1 is the precision of the method . This could be adequately summarized in the text by reporting an overall average precision (expressed as % RSD) for all brands tested . Figure 1 - As a chromatographer, I like to see chromatograms . However, all relevant visual information in Figure 1 is compacted into about 1 inch of space (t< 5-10 min) and is not very illuminating even at the expansion submitted . If reduced and reproduced in a journal, it will certainly be useless information . I suggest enlarging the timescale for the figure dramatically, eliminating everything after about 15 minutes . http://legacy.library.ucsf.edu/tid/shf01d00/pdf 3
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