From: verdant@ucs.umass.edu (Sol Lightman) Newsgroups: alt.drugs Subject: Lung Cancer MJ/Tobacco Date: 5 May 1993 05:25:54 GMT Message-ID: <1s7j52$dc0@nic.umass.edu> |A thank you to Lamont Granquist (sp?) who origionally posted this |article. I dug up the remaining letters and typed them in. |Just to keep things straight |(-- This is me This is the quoted article. Winters-TH, Franza-JR, Radioactivity in Cigarette Smoke, New England Journal of Medicine, 1982; 306(6): 364-365 (reproduced w/o permission) To the Editor: During the 17 years since the Surgeon General's first report on smoking, intense research activity has been focused on the carcinogenic potential of the tar component of cigarette smoke. Only one definite chemical carcinogen -- benzopyrene -- |see correction in follow-up letters, many other identified |chemical carcinogens are present. The question is, what is their |relative risk compared with the "radioelements'' has been found. Conspicuous because of its absence is research into the role of the radioactive component of cigarette smoke. The alpha emitters polonium-210 and lead-210 are highly con- centrated on tobacco trichomes and insoluble particles in cigarette smoke (1). The major source of the polonium is phosphate fertilizer, which is used in growing tobacco. The trichomes of the leaves con- centrate the polonium, which persists when tobacco is dried and processed. Levels of Po-210 were measured in cigarette smoke by Radford and Hunt (2) and in the bronchial epithelium of smokers and nonsmokers by Little et al. (3) After inhalation, ciliary action causes the insoluble radioactive particles to accumulate at the bifurcation of segmental bronchi, a common site of origin of bronchogenic carcinomas. In a person smoking 1 1/2 packs of cigarettes per day, the radia- tion dose to the bronchial epithelium in areas of bifurcation is 8000 mrem per year -- the equivalent of the dose to the skin from 300 x-ray films of the chest per year. This figure is comparable to total- body exposure to natural background radiation containing 80 mrem per year in someone living in the Boston area. It is a common practive to assume that the exposure received from a radiation source is distributed throughout a tissue. In this way, a high level of exposure in a localized region -- e.g. bronchial epithelium -- is averaged out over the entire tissue mass, suggest- ing a low level of exposure. However, alpha particles have a range of only 40 um in the body. A cell nucleus of 5 to 6 um that is traversed by a single alpha particle receives a dose of 1000 rems. Thus, although the total tissue dose might be considered negligible, cells close to an alpha source receive high doses. The Po-210 alpha activity of cigarette smoke may be a very effective carcinogen if a multiple mutation mechanism is involved. Radford and Hunt have determined that 75 per cent of the alpha activity of cigarette smoke enters the ambient air and is unab- sorbed by the smoker, (2) making it available for deposit in the lungs of others. Little et al. have measured levels of Po-210 in the lungs of nonsmokers that may not be accounted for on the basis of natural exposure to this isotope. The detrimental effects of tobacco smoke have been considerably underestimated, making it less likely that chemical carcinogens alone are responsible for the observed incidence of tobacco-related carcinoma. Alpha emitters in cigarette smoke result in appreciable radiation exposure to the bronchial epithelium of smokers and probably secondhand smokers. Alpha radiation is a possible etio- logic factor in tobacco-related carcinoma, and it deserves further study. Thomas H. Winters, M.D. Joseph R. Di Franza, M.D. University of Massachusetts Worcester, Ma 01605 Medical Center 1. Martell EA. Radioactivity of tobacco trichomes and insoluble cigarette smoke particles. Nature. 1974; 249:215-7. 2. Radford EP Jr, Hunt VR. Polonium-210: a volatile radioelement in cig- arettes. Science. 1964; 143:247-9 3. Little JB, Radford EP Jr, McCombs HL, Hunt VR. Distribution of po- lonium-210 in pulmonary tissues of cigarette smokers. N Engl J Med. 1965; 273:1343-51. Responses to this letter: NEJM 307(5):309-313. reproduced w/o permission To the Editor: In a letter in the Feb 11 issue, Winters and DiFranza (1) correctly point out that alpha radiation from polonium-210 is a possible causal factor in tobacco-related carcinoma, but they incorrectly state that "inhaled'' Po210 is a factor and that research on this important possibility has been neglected. I will briefly review recent pertinent research. Radford and Hunt (2) first suggested that alpha radiation from Po210 in cigarette smoke may be important in the genesis of bronchial cancer. Little et al. (3) found surprisingly high concentrations of Po210 at single bronchial bifurcations in seven of 37 cigarette smokers. Holtzman and others (4 - 6) raised doubts about the validity of these observations because inhaled volatile Po210 is soluble and rapidly cleared. Subsequently, I determined (7) that lead-210 (a beta-emitting precursor of Po210) is highly concentrated in tobacco trichomes and that trichome combustion in burning cigarettes produces insoluble, Pb210-enriched particles in mainstream smoke. Thus, the high concentrations of Po210 observed at segmental bifurcations (4 - 6) can be explained by the persistence of insoluble, Pb210-enriched particles deposited at bifurcations and by the ingrowth of Po210 in these particles. (7,8) Radford and Martell (9) confirmed that the excess Po210 in the bronchial epithelium of smokers is accomplished by a larger excess of Pb210. Fleischer and Parungo (10) provided experimental evidence indicating that radon decay products and Pb210 are concentrated on trichome tips. Mechanisms of accumulation of Pb210 on tobacco trichomes are discussed by Martell and Poet. (11) Two recent studies (12,13) indicate that alpha radiation from inhaled indoor radon progeny may explain the incidence of lung cancer in nonsmokers. Martell and Sweder (14) report that indoor radon decay products that pass from the room air through burning cigarettes into mainstream smoke are present in large, insoluble smoke particles that are selectively deposited at bifurcations. Thus, the smoker receives alpha radiation at bronchial bifurcations from these three sources: from indoor radon progeny inhaled between cigarettes, from Po214 in mainstream smoke particles, and from Po210 that grows into Pb210 enriched particles that persist at bifurcations. |to aviod confusion, when they say Po210 grows into Pb210 enriched |particles, they mean that the Pb210 breaks down leaving Po210 deposits |in its place. I estimate that the cumulative alpha dose at the bifurcations of smokers who die of lung cancer is about 80rad (1600rem) -- a dose sufficient to induce malignant transformations by alpha interactions with basal cells. |This is the clincher here, for me. If Martell's estimate of the dosage |at bifurcations is anywhere near accurate, then Po210 must account for |a large portion of the lung cancer risk from tobacco. Edward A Martell, Ph.D. National Center for Atmospheric Research Boulder, CO 80307 1. Winters TH, DiFranza JR. Radioactivity in Cigarette Smoke. NEJM 1982 306:364-365 2. Radford EP, Hunt VR. Polonium-210: a volatile radioelement in cigarettes. Science. 1964; 143:247-249 3. Little JB, Radford EP, McCombs HL, Hunt VR. Distribution of polonium-210 in pulminary tissues of cigarette smokers. NEJM. 1965; 273:1343-1351 4. Holtzman RB, Ilcewicz FH. Lead-210 and polonium-210 in tissues of cigarette smokers. Science. 1966; 153:1259-1260 5. Little JB, Radford EP. Polonium-210 in bronchial epithelium of cigarette smokers. Science. 1967; 155:606 6. Holtzman RB. Polonium-210 in bronchial epithelium of cigarette smokers. Science. 1967; 155:607 7. Martell EA. Radioactivity in tobacco trichomes and insoluble cigarette smoke particles. Nature. 1974; 249:215-7 8. Martell EA. Tobacco radioactivity and cancer in smokers. Am Sci. 1975; 63:404-412 9. Radford EP, Martell EA. Polonium-210: lead-210 ratios as an index of residence times of insoluble particles from cigarette smoke in bronchial epithelium. In: Walton WH, ed. Inhaled particles, part 2. Oxford: Pergamon Press, 1977:567-580 10.Fleischer RL, Parungo FP. Aerosol particles on tobacco trichomes. Nature. 1974; 250:158-159 11.Martell EA, Poet SE. Radon Progeny on Biological Surfaces and their effects. In: Vohra KG, et al., eds. Proceedings, Bombay Symposium on Natural Radiation in the Environment. New Delhi: Wiley Eastern Ltd., 1982 12.Evans RD, Harley JH, Jacobi W, Mclean AS, Mills WA, Stewart CG. Estimate risk from environmental exposure to radon-222 and its decay products. Nature. 1981;290;98-100 13.Harley NH, Pasternack BS. A model for predicting lung cancer risks induced by environmental levels of radon daughters. Health Phys. 1981; 40:307-16. 14.Martell EA, Sweder KS. The roles of polonium isotopes in the etiology of lung cancer in cigarette smokers and uranium miners. In: Gomez M, ed. Proceedings of a symposium on radiation hazards in mining. New York: American Institute of Mining Engineers, 1982:383-389. ----------------- To the Editor: The presence of Po210 and Pb210 in cigarette smoke may help to explain a paradox found in smokers of low-tar, low-nicotine cigarettes. Hammond et al. (1) noted that the number of deaths from lung cancer was greater in subjects who smoked 20 to 39 low-tar, low-nicotine cigarettes a day than in those who smoked one to 19 high-tar, high-nicotine cigarettes a day. Thus, the number of cigarettes smoked may be more important than their tar and nicotine content. Two features of low-tar low-nicotine cigarettes that help to reduce the amounts of tar in inhaled smoke may have little effect or adverse effects on the amounts of Po210 and Pb210 in inhaled smoke. In the first place, the use of higher porosity paper and perforated filters may enhance the completeness of combustion. Although this may decrease the tar and nicotine content in inhaled smoke, it may increase the pyrolysis of trichomes, resulting in smoke particles with higher specific activities of Pb210. Secondly, cigarette filters have been shown to have no noticeable protective effect against Po210 inhalation. (2) If Po210 and Pb210 contribute to tobacco related cancer, then the number of cigarettes smoked may be more important than the tar or nicotine content. Although intensive effort has been successful in producing low-tar, low-nicotine cigarettes, perhaps future research should be aimed toward the development of low Po210, low Pb210 cigarettes. Jeffrey I. Cohen M.D. Duke University Medical Center Durham, NC 27710 1. Hammond EC, Garfinkel L, Seidman H, Lew EA. Some Recent findings concerning cigarette smoking. In: Origins of Human Cancer. New York: Cold Spring Harbor Laboratory, 1977:101-112 2. Rajewski B, Stahlholfen W. Polonium-210 activity in the lungs of cigarette smokers. Nature. 1966; 209:1312-1313 ----------------------- To the Editor: Contrary to the contention of Winters and DiFranza that research into the carcinogenic potential of the radioactive component of cigarette smoke is conspicuous by its absence, we and others have studied and reported on this risk since the theory was first proposed by Radford and Hunt in 1964. (1) Within five years of the initial report that the radioactive alpha emitter Po210 was present in mainstream smoke and in samples of bronchial epithelium from cigarette smokers, results from over two dozen related studies were published. The source of the Po210 and Pb210 (The beta emitter Pb210 is the long lived precursor that supports the Po210) was investigated, (2) the contents of these nuclides in various tobaccos documented, (3) the fraction transferred to the mainstream or sidestream smoke (or both) determined, (4) and the concentration in the whole lungs of smokers and nonsmokers measured. (5) Measurements made with cigarette smoke condensate demonstrate that although radium and thorium are also present in cigarette smoke, 99% of the alpha activity is from Po210. (6) Measurements of the whole lungs of smokers and exsmokers show that the inhaled Po210 is retained in the lower lung. (7) A relatively new detection technique using nuclear-track-etch film has allowed us to determine the amount and microdistribution of alpha activity on the bronchial mucosa in fresh autopsy specemins. (8) We examined about one-fourth of the upper respiratory tract in each of seven persons (Three smokers, two exsmokers, and two nonsmokers). A few areas of slightly elevated alpha activity were found in each of the bronchial trees examined except that of one young smoker, in which efficient bronchial clearance would be expected. The average dose rate to the basal cells of the bronchial epithelium from alpha activity in these seven persons ranged from 2.0 to 40mrem per year. For comparison, the natural background dose from inhaled radon-daughter alpha activity is about 2000mrem per year. One area of a few square millimeters, containing markedly elevated activity, was found in the bronchii of an older smoker. This area could deliver an annual dose of about 20,000mrem, comparable to the results originally reported by Bradford and Hunt. This activity can lead to a lifetime dose similar to the alpha dose that appears to yield an elevated risk of lung cancer in underground miners. However, the total dose cannot be calculated, since the residence time of such an alpha emitting spot on the bronchial tree is not known. The importance of proper assessment of the risk to cigarette smokers from radionuclides in the smoke cannot be overstated. In veiw of the present knowledge, it is improbable that a single area of a few square millimeters of high alpha activity in the bronchial tree is important. Nonetheless, Po210 is the only component in cigarette smoke tar that has produced cancers by itself in laboratory animals as a result of inhalation exposure. (9) |I would question the way they casually play off the signifigance of |the hot spot here. Also, I find it rather unusual that locating |and isolating a single component of tobacco smoke which does produce |lung cancer by inhalation did not result in a huge investigation of Po210. |Or at least better media coverage. We firmly believe that the role of alpha radiation in tobacco related carcinogenesis deserves further study. The techniques to define its role in this disease are now available. Beverly S. Cohen, Ph.D. Naomi H. Harley, Ph.D. New York University School of Medicine New York, NY 10016 1. Radford EP, Hunt R. Polonium-210: a volatile radioelement in cigarettes. Science. 1964; 143:247-249 2. Tso TC, Harley NH, Alexander LT. Source of Pb210 and Po210 in tobacco. Science. 1966; 153:880-882 3. Black SC, Bretthauer EW. Polonium in tobacco. Radiat Health Data Rep. 1968;9:145 4. Ferri ES, Christiansen H. Lead-210 in tobacco and cigarette smoke. Public Health Rep. 1967; 82:828 5. Hill CR. Polonium-210 in man. Nature 1965; 208:423-428 6. Cohen BS, Eisenbud M, Harley NH. Alpha radioactivity in cigarette smoke. Radiat Res. 1979;83:190-196 7. Cohen BS, Eisenbud M, Wrenn ME, Harley NH. Distribution of polonium-210 in the human lung. Radiat Res. 1979;79:162-168 8. Cohen BS, Eisenbud M, Harley NH. Measurement of the alpha activity on the mucosal surface of the human bronchial tree. Health Phys. 1980:619-632. 9. Yuille CL, Berke HL, Hull T. Lung cancer following Pb210 inhalation in rats. Radiat Res. 1967;31:760-774 ---------------- To the Editor: The letter of Winters and DiFranza has renewed the earlier suggestion that the radioisotope Po210 may have an important role in the induction of lung cancer in smokers. In particular, it is claimed that the radionuclide may be deposited very inhomogeneously in the bronchial epithelium, in the form of a limited number of relatively "hot'' particles, and that such hot particles may be much more effective carcinogenically than the same amount of radioactivity would be if it were more uniformly distributed. The basis of both these claims must be questioned. Evidence on the question of the carcinogenicity of hot particles has been reviewed by the International Commission on Radiological Protection, (1) which found the actual situation to be just the reverse of that suggested by the correspondents. The evidence cited for the actual formation of hot particles (2) comes from a study of the Po210 in a series of several very small samples of bronchial epithelium (usually less than 25 mg) collected from smokers' lungs. In these measurements, the activities in individual samples were so low that for a proportion at least, only about 20 counts were recorded in a counting period of three to seven days against a background of 40 counts. Proper analysis of the statistical validity of these observations was not given by the original authors and is not possible from their reported data. Contrary evidence, not cited by the correspondents, is provided by a somewhat earlier paper (3) that reported the results of auto radiographic examination of excised segments of bronchial epithelium; this study found no evidence of surface concentrations of alpha activity of more than 0.01pCi per square centimeter, corresponding to a mean dose rate of about 10mrem per year. Finally, the correspondents' suggestion that the "major source of the polonium is phosphate fertilizer'' is not substantiated and is at variance with published data (3,4) indicating that it originates as atmospheric fallout of the decay products of natural radon-222. |This guy sounds like he knows what he's talking about, see the |rebuttal in the last letter before you make up your mind, though C.R. Hill, M.D. Institute of Cancer Research Royal Marsden Hospital Sutton, Surrey SM2 5PX, England 1. International Commission on Radiological Protection. Biological effects of inhaled radionuclides, ICRP Publication 31, Section G, 86-92. Ann ICRP. 1980;4 (No. 1/2) 2. Little JB, Radford EP, McCombs HL, Hunt VR. Distribution of polonium-210 in pulminary tissues of cigarette smokers. NEJM 1965;273:1343-1351 3. Hill CR. Polonium-210 in man. Nature. 1965; 208:423-428 4. Hill CR. Lead-210 and polonium-210 in grass. Nature, 1960; 187:211-212 ------------------ To the Editor: The Surgeon General's recent denunciation of tobacco smoking and the American Cancer Society's pessimistic prognosis that lung cancer will be the number one cause of death from cancer in women by 1985 (1) provide timely emphasis on the recent NEJM letter on radioactive |anyone know if this came true, or is breast cancer still in the lead? |Just wondering... alpha emitters in tobacco smoke. Some of the further study encouraged by Winters and DiFranza has in fact been performed, yielding results far more foreboding than expected. In two separate studies, Little et al. (2,3) have induced respiratory tumors in hamsters by intratracheal instillation of Po210 in various amounts down to less than one-fifth that inhaled by a heavy cigarette smoker (one who consumes two packs a day) during 25 years. The incidence of tumors at the lowest dose was 13%, including borderline carcinomas, and was 11% for frankly malignant tumors. Contrary to the expected results of most radiobiologists, dose reduction did not result in either a constant dose-response ratio (the linear response hypothesis) or a larger dose-response ratio (The threshold or sigmoid hypothesis) but instead produced a marked decrease in the dose-response ratio. In one study, a reduction in activity from 0.700microCi of Po210 instilled to 0.00375microCi of Po210 instilled -- about a two hundred-fold decrease -- resulted in a decrease in the incidence of tumors from 61% to 13% (including borderline cases) -- only a fourfold decrease. |So this means, as this guy will get to, that doubling your radiation |exposure at low levels (like the one you are experiencing right now) |more than doubles your cancer risk. |Of course, it does have to become asymptotic at 100%, but I, for |one, do not care to get that far... This decrease in the dose-response ratio with decreasing dose has also been observed in other studies of the effects of low dose alpha radiation and other radiation particles with high linear energy transfer (LET). In a study of osteosarcoma induction by alpha radiation, Muller et al. (4) had over a 100-fold decrease in the dose-response ratio from their highest dose (1500rad) to their lowest dose (15rad). For neutron radiation, Rossi et al. (5) found similar results, with leukemia induction having the smallest dose-response ratio in the lowest dose in survivors of the atomic bomb. Similarly, Hall et al. (6) found that both dose protraction and dose reduction for neutron radiation increased the cell-lethality-dose ratio of hamster cells in vitro. The importance of these results with low dose irradiation by high LET particles should not be overlooked. Doses in the range of several thousand to 10^5 rad have generally been necessary for the experimental induction of lung cancer by beta or gamma radiation (with low LET), (7,8) as compared with the studies by Little et al., in which the lowest dose of 15rad (0.00375microCi in the lung volume for the lifetime of the hamsters) induced cancer at an incidence of about 13%. Presumably, the high density of ionization along the track of alpha radiation (about one ion pair for every 2 Angstrom traveled) and other high-LET radiation is the prime factor causing Po210 to be an extremely efficient carcinogen. Clearly, further work is warranted in this area, but we should not hesitate to disseminate the information already at hand -- that the alpha-radiation exposure to the lungs of tobacco smokers is extremely important. Walter L. Wagner, B.A. Veterans Administration Medical Center San Francisco, CA 94121 1. American Cancer Society. Ca: a cancer journal for clinicians. Jan/Feb 1981;Vol 31, No. 1 2. Little JB, Kennedy AR, McGandy RB. Lung cancer induced in hamsters by low doses of alpha radiation from polonium-210. Science. 1975; 188:737-738 3. Little JB, O'Toole WF. Respiratory tract tumors in hamsters induced by benz(a)pyrene and Po210 radiation. Cancer Res. 1974; 34:3026-3039 4. Muller WA, Gossner W, Hug O, Luz A. Late effects after incorporation of the short-lived alpha-emitters Ra224 and Th227 in mice. Health Phys. 1978; 35:33-55 5. Rossi HH, Mays CW. Leukemia risk from neutrons. Health Phys. 1978; 34:355-360 6. Hall EJ, Rossi HH, Roizin LA. Low-dose-rate irradiation of mammalian cells with radium and californium-252. Radiology. 1971; 99:445-451 7. Cember H. Radiogenic Lung Cancer. Prog Exp Tumor Res. 1964; 4:251. 8. Sanders CL, Thompson RC, Blair WJ. AEC Symp Ser. 1970; 18:285. --------------------- To the editor: The letter by Winters and DiFranza rivets much needed attention on the earlier finding of Radford and Hunt, (1) which is crucial to an understanding of the pathogenesis of smoking diseases. (2,3) Although Winters and DiFranza tellingly describe the mechanisms by which Po210 on insoluble particles in cigarette smoke causes lung cancer, they neglect the even more important matter of how Po210 and other mutagens from tobacco smoke cause malignant neoplasms, degenerative cardiovascular diseases, and other diseases throughout the body of smokers (Table 1). |Though he may be right, I have to moan at the way this guy just took |this data and slapped a new header on it. It's not even descriptive! |What exactly do the numbers in the feilds mean? Ugh. TABLE 1. Effects of Smoking on Tissues Directly and Indirectly Exposed to Radiation in Current Cigarette Smokers* ============================================================= Cause of Death Number of Deaths Observed/ Expected (ratio) Observed|Expected All causes 36,143 20,857 1.73 Emphysema 1,201 81 14.83 Cancer: Of directly exposed tissue 3,061 296 10.34 Of buccal cavity 110 26 4.23 Of pharynx 92 7 13.14 Of larynx 94 8 11.75 Of lung and bronchus 2,609 231 11.29 Of esophagus 156 24 6.50 Of indirectly exposed tissue 4,547 3,292 1.38 Of stomach 390 257 1.52 Of intestines 662 597 1.11 Of rectum 239 215 1.11 Of liver and biliary passages 176 75 2.35 Of pancreas 459 256 1.79 Of prostate 660 504 1.31 Of kidney 175 124 1.41 Of bladder 326 151 2.16 Of brain 160 152 1.05 Malignant lymphomas 370 347 1.07 Leukemias 333 207 1.61 All other cancers 597 407 1.47 All cardiovascular diseases 21,413 13,572 1.58 Coronary heart disease 13,845 8,787 1.58 Aortic aneurysm 900 172 5.23 Cor pulmonale 44 8 5.50 All other cardiovascular 6,624 4,605 1.44 Ulcer of stomach, duodenum or jejunum 289 93 3.10 Cirrhosis of liver 404 150 2.69 ========================================================= *Data adapted from Rogot and Murray. (4) |At any rate: here I put forth the question -- if some of these |ailments are generated at ten times+ the rate in smokers as in |non smokers, as this table indicates, supposing marijuana is |carcinogenic in the same manner as tobacco, wouldn't it be relatively |easy, even in this country, to find a correlation?? I submit |this as a second proof that the chemical tar component has little to do |with the majority of lung cancer deaths Volatilized, soluble Po210, produced at the burning temperature of cigarettes, (1) is cleared from the bronchial mucosa at the expense of the rest of the body, being absorbed through the pulmonary circulation and carried by the systemic circulation to every tissue and cell, causing mutations of cellular genetic structures, deviation of cellular characteristics from their optimal normal state, accelerated aging, and early death from a body-wide spectrum of diseases, reminiscent of the disease and mortality patterns afflicting early radiologists and others with long-term exposure to x-rays and other forms of ionizing radiation. (5,6) The proof of circulating mutagens from smoking is that Po210 and other mutagens can be recovered not only from tobacco smoke and bronchial mucosa, but also from the blood and urine of smokers. (1,7) R.T. Ravenholt M.D., M.P.H. Centers For Disease Control Washington Office Rockville, MD 20857 1. Radford EP Jr, Hunt VR. Polonium-210: a volatile radioelement in cigarettes. Science. 1964; 143:247-249 2. Ravenholt RT. Malignant cellular evolution: an analysis of the causation and prevention of cancer. Lancet. 1966; 1:523-526 3. Ravenholt RT, Lavinski MJ, Nellist D, Takenaga M. Effects of smoking upon reproduction. Am J Obstet Gynecol. 1966; 96:267-281 4. Rogot E., Murray JL. Smoking and causes of death among U.S. veterans: 16 years of observation. Public Health Rep. 1980:213-222 5. Warren S. Longevity and causes of death from irradiation in physicians. JAMA. 1956; 162:464-468 6. National Academy of Sciences-National Research Council. Long term effects of ionizing radiation from external sources. Washington D.C.: National Research Council, 1961. 7. Office on Smoking and Health. Smoking and Health: a report of the Surgeon General. Rockville, MD: Office on smoking and health, 1979. (DHEW publication no. [PHS]79-50066). ------------------ To the editor: We concur with Drs. Winters and DiFranza that the scientific and medical community as well as public health officials should be more concerned with the detrimental effects of cigarette smoking. Reviews on the carcinogenic effect of cigarette smoke are made available to United States physicians at regular intervals through the Surgeon General's reports entitled Smoking and Health. (1) From these reports it is clear that benzo(a)pyrene is by far not the only carcinogen identified in cigarette smoke. Benzo(a)pyrene serves merely as an indicator for the wide spectrum of carcinogenic polycyclic hydrocarbons, all of which are pyro synthesized by the same mechanism during smoking. Aside from these hydrocarbons, cigarette smoke contains other carcinogens such as aza-arenes, aromatic amines (including beta-napthylamine), nickel, volatile nitrosamines, and especially tobacco-specific N-nitrosamines. (1-3) The N-nitrsamine compounds are formed by nitrosation of nicotine and other alkaloids; their concentrations in tobacco and smoke exceed those of nitrosamines found in other consumer products by at least several hundred fold. These nitrosamines are probably formed from nicotine in vivo. (2,3) Above all, one needs to consider that the carcinogenic potential of tobacco is a composite effect of tumor initiators, tumor promoters, or co-carcinogens, and organ-specific carcinogens. (1,2) Dietrich Hoffmann, Ph.D. Ernst L. Wynder, M.D. American Health Foundation New York, NY 10017 1. Office on smoking and health. Smoking and Health: a report of the Surgeon General. Rockville, MD: Office on smoking and health, 1979. (DHEW Publication No. [PHS]79-50066) 2. Wynder EL, Hoffman D. Tobacco and health: a societal challenge. NEJM 1979; 300:894-903 3. Hofmann D, Adams JD, Brunnemann KD, Hecht DD. Formation, occurrence and carcinogenesity of N-nitrosamines in tobacco products. Am. Chem. Soc. Symp. Ser. 1981; 174:247-273 -------------- To the editor: We thank Dr. Martell and Drs. Cohen and Harley for their reviews of the literature. Judging by the response to our original letter, research into the radioactive component has been in progress since the early 1960's, but the existence of this research is largely unknown outside a small segment of the scientific community. We were gratified to receive hundreds of phone calls from smokers who quit on learning about the alpha radiation in cigarette smoke. Hill examined the lungs of only two smokers old enough to have metaplastic lesions. In addition, he analyzed whole bronchial specemins weighing 5g to 15g, of which only 2% by weight was epithelium. His result of 0.007 pCi per gram of tissue is in reasonable agreement with Little's result of 0.012pCi per gram of whole bronchus and thus does not disprove the existence of hot spots. In addition, the accumulation of Pb210 on tobacco leaves is from natural and unnatural radon-222 decay products and from phosphate fertilizers. | I really wish they had cited the source for this last part, as it |hasn't been documented to my total satisfaction |All I have is a chart of the concentration of Po210 and Pb210 in |various tobacco from different parts of the world. It shows India |as the lowest. The US fertilizes with phosphates rich in Radium and |other radioisotopes. It was second highest. I don't know what the |Soviet Union is up to as far as fertilizer, but it got the dubious |distinction of first place. Maybe they farm their tobacco near |Chebalinsk (sp?) (site of cover up of nuclear disaster bigger than |Chernobal) |-\ Of course by now anywhere in the Soviet Union is New Jersey. |[gonna have to look up the name of that place again, where's my |Mother Jones??] We thank Dr. Wagner for pointing out that alpha radiation now appears to be 1000 times more carcinogenic than gamma radiation. Standard practice reguards alpha radiation as only 10 to 20 times as carcinogenic as gamma radiation. |Sing along now: |That's a good thing to know! |That's a very good thing to know! |Makes me want to jump and sing! |I'm so glad I know that thing! The growing list of malignant diseases associated with smoking, presented by Dr. Ravenholt, begs for causal explanation. Smokers have higher levels of Po210 in the lungs, bone blood and urine. (1-3) Higher levels of Po210 have been consistently found in smokers in the liver, kidney, spleen, pancreas, and gonads. (4,5) A study with an adequate number of subjects would probably demonstrate a significant difference. The Po210 must be strongly considered as a cause of these cancers. Drs. Cohen and Harley report finding one "hot spot'' on studying the alpha activity of alpha Po210 in tracheal autopsy specemins of seven people, three of whom were smokers. (6) This supports Little and his colleagues' previous findings of "hot spots'' in 7 out of 37 smokers. We thank Drs. Hoffmann and Wynder for correcting us about the variety of chemical carcinogens present in cigarette smoke. It is possible that chemicals and Po210 act as cocarcinogens in the following manner. Chemical and possibly physical agents create metaplastic nonciliated epithilial lesions. Auerbach demonstrated such lesions in 100% of heavy smokers. (7) The Po210 present on insoluble particles gains entrance to epithelial cells in such non-ciliated areas of mucous stagnation. Ingrowth of Po210 from the decay of Pb210 results in high doses of alpha radiation to already metaplastic cells. (8) Continued smoking ensures a steady delivery of Pb210 to these stagnant sites. Little and his co-workers have demonstrated synergism between benzo(a)pyrene and Po210 in an animal model. (9) In view of the potential role of alpha radiation in a variety of tobacco related neoplasias, we believe that this area deserves more intense research. We find it surprising that the National Cancer Institute, with an annual budget of $500 million, has no active grants on alpha radiation as a cause of lung cancer (National Cancer Institute: personal communication). We have found when educating smokers that more are encouraged to quit as they learn of the presence of radiation in cigarette smoke. |Ahh. My point. Glad I'm not the only owner. Joseph R. DiFranza, M.D. Thomas H. Winters, M.D. University of Massachusetts Medical Center Worcester, MA 01605 1. Little JB, Radford EP Jr, McCombs HL, Hunt VR. Distribution of polonium-210 in pulminary tissues of cigarette smokers. NEJM 1965; 273:1343-1351 2. Radford EP Jr, Hunt VR. Polonium-210: a volatile radioelement in cigarettes. Science. 1964; 143:247-249 3. Holtzman RB, Ilcewicz FH. Lead 210 and Po210 in tissues of cigarette smokers. Science. 1966; 153:1259-1260 4. Blanchard RL. Concentrations of Pb210 and Po210 in human soft tissues. Health Phys. 1967; 13:625-632. 5. Hill CR. Polonium 210 in man. Nature. 1965; 208:423-428 6. Cohen BS, Eisenbud M, Harley NH. Measurement of the alpha radioactivity on the mucosal surface of the human bronchial tree. Health Phys. 1980; 619-32 7. Auerbach O, Stout AP, Hammond EC, Garfinkel L. Changes in bronchial epithelium in relation to cigarette smoking and in relation to lung cancer. NEJM 1961; 265:253-67 8. Radford EP, Martell EA. Polonium 210/Lead 210 ratios as an index of residence times of insoluble particles from cigarette smoke in bronchial epithelium. In: Walton WH, ed. Inhaled Particles. IV. Part 2, Oxford, Pergamon Press, 1977:567-580 9. Little JB, McGrandy RB, Kennedy AR. Interactions between polonium 210 alpha radiation, benzo(a)pyrene, and 0.9% NaCl instillations in the induction of experimental lung cancer. Cancer Res. 1978; 38:1929-1935. --------------------------------------------------------------------------- |Also, a thank you to the origional poster of this article, whose |name I have unfortunately lost in one of those funky little |crevasses that you can't help but find every time you learn a new |text editor. ===================================== 6 on EPA Panel Tied to Tobacco Group ===================================== Chicago Tribune, Friday, November 9, 1990, page 3. "NEW YORK (AP) Six of the 16 members of a newly appointed Environmental Protection Agency panel considering the health risks of second-hand cigarette smoke have ties to a tobacco industry research organizations, documents show. A seventh member of the panel was appointed on the recommendation of the Philip Morris tobacco company, EPA officials said. "They've stacked the deck with people who have closed ties to the tobacco industry,"said Dr. Alan Blum, a founder of the anti-smoking group, Doctors Ought to Care. "It's pathetic" "We were concerned about the appearance of conflict of interest," said Donald Barnes, staff director of the EPA's scientific advisory board. But he said the link between the panel members and the tobacco organization "does not cause any question to be raised [sic] about their technical capabilities." The panel is to review the scientific accuracy and objectivity [sic] two forthcoming EPA reports on the health effects of passive smoking. Six members are connected with the Center for Indoor Air Research of Linthicum, Md., according to the centers' publications. The center is financed by Philip Morris, R.J Reynolds Tobacco Co. and Lorillard Corp., three of the nation's largest tobacco companies. Its board of directors are made up of employees of those companies, said a center administrator. The chairman of the EPA passive-smoking panel, Morton Lippmann of New York University, is on the science advisory board of the tobacco industry center. Lippmann and another member of the EPA panel, Dr. Jonathan Samet of the University of New Mexico, helped devise the center's research agenda. Samet and three other members of the EPA panel are listed as "peer reviewers" for the center. Yet another member, of the EPA panel, Delbert Eatough of Brigham Young University, received research funds from the center. A seventh member of the panel, Geoffrey Kabat of the American Health Foundation, had been recommended [sic] by Philip Morris, EPA officials said. [...] The makeup of the EPA panel aroused controversy when it was reported last month that the agency had dismissed Dr. David Burns from the panel after the tobacco industry lobbied to get rid of him. Burns, of the University of California at San Diego, was the author of the U.S. Surgeon General's report on passive smoking and is regarded by his colleagues as a leading authority on passive smoking. He was reinstates to the EPA panel after his dismissal was disclosed. Lippmann said he didn't see any problems working with the EPA and with the tobacco research center. [...] Lippmann said three of his colleagues at New York University's Institute of Environmental Medicine, where Lippmann works, have received grants from the tobacco industry group. The largest grant was for $250,000 [sic], he said. Eatough, who has received research funds from R.J. Reynolds as well as the Center for Indoor Air Research [above-mentioned tobacco-industry corporations "center"] , said the receipt of such money does not compromise his objectivity. [...] ################################################################## ----------------------------------------------------------------------- Brief Prepared by UMASS CANNABIS verdant@titan.ucs.umass.edu For a copy of this brief, without my ramblings but with my wonderfully terrifying pamphlet, mail my account like so: To: verdant@titan.ucs.umass.edu Subject: {{{tobacco}}} Brian -- The University of Massachusetts at Amherst | _________,^-. Cannabis Reform Coalition ( | ) ,> S.A.O. Box #2 \|/ { 415 Student Union Building `-^-' ? ) UMASS, Amherst MA 01003 verdant@titan.ucs.umass.edu |____________ `--~ ; \_,-__/ * To find out about our on-line library, mail a message with the * pattern "{{{readme}}}" contained IN THE SUBJECT LINE. * You will be mailed instructions; your message will be otherwise ignored
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