Correspondence P, Fry SA. Brain cancer and non-occupa- tional risk factors: case-control study among workers at nuclear facilities. Am J Public Health 1987;9:1180-2. 5 Inskip PD, Linet MS. Heineman EF. Etiology of brain tumours in adults. Epidemiol Rev 1995;17:382-414. 6 Julian J, Muir DCF. A Study of cancer incidence in Ontario nickel workers. Toronto: Occupational Disease Panel, 1996. 7 Ashmore JP, Grogan D. The national dose reg- istry for radiation workers in Canada. Radiation Protection Dosimetry 1985;11: 95-100. 8 Darby SC, Whitely E, Howe GR, Hutchings SJ, Kusiak RA, Lubin JH, et al. Radon and cancers other than lung cancer in under- ground miners: a collaborative analysis of 11 studies. J Nad Cancer Inst 1995;87:378-84. 9 National Research Council. Health effects of exposure to low levels of ionizing radiation, BEIR V. Washington DC: National Academy Press, 1990. 10 Savitz DA, Loomis DP. Magnetic field expo- sure in relation to leukemia and brain cancer mortality among electric utility workers. Am J Epidemiol 1995;141:123-34. 11 Theriault G. Goldberg M, Miller AB, Armstrong B, Guenel P. Deadman J, et al. Cancer risks associated with occupational exposure to magnetic fields among electric utility workers in Ontario and Quebec, Canada and France: 1970-89. Am J Epidemiol 1994;139:550-72. Lung cancer in asbestos cement workers in Denmark Editor-This paper' is a tribute to Edith Raffn and Elsebeth Lynge who have been involved in all three analyses of mortality and cancer morbidity in this Danish asbestos cement worker population, and to Johannes Clemmesen, father of their Cancer Register. The history of studies of asbestos workers tends to follow a pattern. When the health of the population studied is found to be plu- perfect or its excess mortality not significant, there has been a tendency to leave well alone. (The astute epidemiologist, after con- ducting a preliminary analysis that seems to show that asbestos exposure was good for you, would decline to proceed further until he had verified the integrity of the popula- tion. But that is another story). The attraction of studying asbestos cement workers (and for that matter asbestos textile workers) was the possibility of being able to evaluate the toxicity of chrysotile. In the event, when excess cancer mortality was found, it would be recalled that for a period there may have been expo- sure to amphibole. This population of Danish asbestos cement workers overall, had the potential for mixed chrysotile and amphibole exposure, but it does include a subset of workers employed exclusively before the introduc- tion of amphibole. Could the authors inform us whether analysis of this valuable group casts any light on the hazards of exposure purely to chrysotile asbestos? MORRIS GREENBERG 74 North End Road London NWJ1 7SY 1 Raffin E, Villadsen E, Engholm G., Lynge E. Lung cancer in asbestos cement workers in Denmark. Occup Environ Med 1996;53: 399-402. Authors' reply-The cohort of asbestos cement workers from Denmark includes 7887 men and 576 women employed between 1928 and 1984.' During the years 1928-40 chrysotile only was used in asbestos cement production. No asbestos was used during the war years Incidence oflung cancer in Danish asbestos cement workers employed during periods where chrysotile only was used Number of cases of lung cancer Group Obs Exp SIR (95% CI) Employed 1929-44: Men 12 6-48 1.9 (0 96-3 2) Workers: Asbestos cement 8 4 04 2-0 (0 9-3 9) Cement only 2 1-55 1-3 (0-1-4-7) Maintenance 2 0-66 3 0 (0-3-10-9) Salaried employees 0 0-23 -(-) Women 0 0-18 Employed 1980-4: Men 0 0-24 (-) Women 0 0 05 -(-) 1941-4. During the years 1945-79 chryso- ment period. tile primary (= 88% of all asbestos used); There were a total of 12 lung cancer but for all years also a small amount of cases; all among men employed 1928-44. amosite (= 11%), and for 1950 to 1969 This gave an increased SIR of borderline some crocidolite (= 1%) were used. During significance (SIR 1 9; 95% CI 0 96-3 2). the years 1980-4 again chrysotile only was The excess number of cases came from used. workers employed in the asbestos cement As reported,' from 1943 to 1990 a total of production and in the maintenance. 223 lung cancer cases were diagnosed The numbers are thus small, but the data among the male cohort members (standard- clearly indicate that the excess lung cancer ised incidence ration (SIR) 1-7; 95% confi- risk found for the total cohort was found dence interval (95% CI) 1-5-2-0). also for the subgroup exposed exclusively to We have now also tabulated the lung can- chrysotile. cer incidence for people employed only dur- ELSEBETH LYNGE ing the years where chrysotile only was used EDITH RAFEN at the factory. This involves 163 people who GERDA ENGHOLM started employment between 1928 and 1940 Danish Cancer Society, Strandboulevarden 49, and ended employment before 1945; and DK-2100 Kobenhaun 0, Denmark 262 people who started employment between 1980 and 1984. We have taken 1 Raffn E, Villadsen E, Engholm G, Lynge E.between 1980and1984. We have taken Lung cancer in asbestos cement workers in advantage also of the fact that specific job Denmark. Occup Environ Med 1996;53: titles were recorded for the early employ- 399-402. BOOK REVIEWS Book review editor: R L Maynard If you wish to order, or require further information regarding the titles reviewed here, please write or telephone the BMJ Bookshop, PO Box 295, London WX1H 9TE. Tel: 0171 383 6244. Fax: 0171 383 6662. Books are supplied post free in the UK and for British Forces Posted Overseas addresses. Overseas customers should add 15% for postage and packing. Payment can be made by cheque in sterling drawn on a UK bank, or by credit card (MasterCard, VISA, or American Express) stating card number, expiry date, and your full name. (The price and availability are occasionally subject to revision by the Publishers.) Smog Alert: Managing Urban Air Quality. By DEREK ELSOM. (Pp 226; L13-95.) 1996. 120 Pentonville Road, London Ni 9BR: Earthscan. ISBN 185383-1921. Smog Alert: Managing Urban Air Quality is a useful introductory book on urban air pollu- tion. The style is apocalyptic and the author delights in providing, especially in the early chapters, details of appalling population growth and worsening air quality in the rapidly expanding cities of the countries in transition from an agricultural to an indus- trial economy. The author has provided extensive footnote references, which I like, to the "grey literature" but almost no refer- ences to the original scientific literature. This is by contrast with his book Atmospheric Pollution: A Global Problem which provides detailed referencing. The author has included a wide range of govem- ment reports in his footnotes: again, I like this, but use of the secondary literature alone makes it difficult to check statements made in the text. Does the book provide a balanced account? Looking closely at those areas with which I am familiar, I am afraid that it does not. For example, the section dealing with asthma and air pollution leaves the impres- sion that the worldwide, rising tide of asth- ma is caused by air pollution. A secondary source not quoted by the author is the Department of Health Report on Asthma and Outdoor Air Pollution. This report made clear, by a detailed examination of the pri- mary literature, that links between air pollu- tion and the prevalence of asthma were far from established. This point has also been made in a recent report of an International Programme of Chemical Safety Workshop on Environmental Chemicals and Respiratory Hypersensitisation. The prevalence of asthma is increasing in the United Kingdom and yet the trend in pollution levels in the United Kingdom urban areas has not been dramatically upward during the past 10 or so years. Other sections of the book also 143 o n A p ril 5 , 2 0 2 1 b y g u e st. P ro te cte d b y co p yrig h t. h ttp ://o e m .b m j.co m / O ccu p E n viro n M e d : first p u b lish e d a s 1 0 .1 1 3 6 /o e m .5 4 .2 .1 4 3 -b o n 1 F e b ru a ry 1 9 9 7 . D o w n lo a d e d fro m http://oem.bmj.com/ Book reviews seem to lean more on popularly accepted views than on hard proof Recent work has shown that air pollutants can increase the response of the airways to allergens; the key question is to what extent does this occur at ambient levels of pollution. This is harder to answer but if not mentioned the reader is left with the impression that the effect is of known importance. The chapters dealing with solutions are helpful. Much useful information has been collected and tabulated. This will be an important source for students, especially as the "grey literature" in this area can be diffi- cult to trace. Costs and benefits are considered but not in great depth. For comparatively wealthy countries, air pollution is a soluble problem, for poor countries this may not be the case for some years yet. Given that industrial countries are inevitably in competition with one another it is not easy to see that rich countries will wish to help the less fortunate to enjoy a clean industrial revolution. Sadly, the old administrative adage "costs lie where they fall" seems to apply on a global scale. In conclusion, this is a useful and inex- pensive book which deals with an important problem. The more advanced reader will wish to follow up some of the author's points in the original literature-if he does so then he will find the picture is less clear cut than presented in Smog Alert. R L MAYNARD Environmental Hazards and Human Health by RICHARD B PHILP. (Pp 306; price ,C55.) 1995. Boca Raton, FL: CRC Press. ISBN 1-56670-133-3. As the author of this title proclaims, it is increasingly necessary for students of environmental sciences to know something of toxicology, and for students of toxicology to know something of the environment; the intention of Environmental Hazards and Human Health is to bridge that gap. The chapter titles range from water pollution through radiation hazards to risk analysis and the Gaia concept. This book is both lively and readable. Its intended aims are ambitious and its content comprehensive, but it somehow falls short of fully meeting its objectives. This may be due to the rather idiosyncratic style and the patchyness of the text. Although it frequently makes interesting reading, the material presented is often sketchy and selective. It also lacks formal referencing. Thus the material sometimes has an anecdotal feel, although balancing this is the author's personal touch and the inclusion of some unusual and useful snippets of material. It seems to be a prerequisite nowadays to preface any text or chapter on toxicology or pharmacology with a quote from Paracelsus. This one is no exception, although the quote used is more accurate than usual. It seems ironic that Paracelsus is so often used in this context as the point he was making referred in fact to the homeopathic usage of known poisons. As a general comment, I was not sure that the introductory quotes in this book contributed significantly. Not surprisingly, perhaps, in a book of this kind covering a very broad range of top- ics, some sections are lengthy and detailed whereas others seem short and superficial. Moreover, the material sometimes seems rather too simplistic and does not always adequately support the review questions given at the end of each chapter. Indeed, I was not convinced about the appropriate- ness of these questions or of the case studies provided. Also, it has to be said that the illustrations are not of the highest quality; they are all in black and white and often rather crude in comparison with the superb graphics increasingly commonplace in books of this ilk. In terms of completeness and top- icality of its contents, I was surprised not to see PM,0 mentioned by name. Nor was there a reference as such to environmental oestro- gens and the increasing evidence regarding the endocrine disrupting properties of chem- icals, which is currently a very topical issue in terms of both scientific and public inter- est. My overriding impression of this book was of a brave, if not wholly successful, attempt to cover all the key issues in this vast subject area. Although perhaps trying to achieve too much, the author nevertheless has produced a reader friendly overview for students needing basic information on a wide range of topics in the environment and health field, and I am sure the book will receive a wide readership. At £55 this hard- back book is reasonable value for money. PAUL HARRISON Traumatic Stress in Critical Occupations, Recognition, Con- sequences, and Treatment. By DOUGLAS PATON, JOHN M VIOLANT. (Pp 245.) 1996. Springfield, Il: Charles C Thomas. ISBN 0- 398-065772. The poet Ralph Waldo Emerson described the simple reality of the experiences of human beings in traumatic situations when he mused "we boil at different degrees". This book attempts to explore not only each person's reaction to traumatic stressful situa- tions, but also the "complex interactions between the person, the traumatic event, and the social and organizational back- ground against which performance takes place". The emphasis here is on understand- ing the stress and trauma phenomena and developing an "effective trauma manage- ment system". This duality of objectives, highlighting the current theory in the field and the practical solutions is laudable. Also, by encompassing the phrase "critical occu- pations", the authors have widened the con- ventional view of traumatic stress being associated with the emergency services only, extending the construct to the "helping pro- fessionals" as well. The book is divided into eight chapters, the first two of which are concerned with a broad overview of the field and by research considerations on methodology and assess- ment strategies. The next four chapters explore specific critical occupations such as emergency medical service workers, the police, and disaster relief agencies. Most of these cover not only the research undertaken but also education, prevention, and support approaches. The last two chapters, from my point of view, are the most interesting, as they explore the training and support for emergency responders and future issues in the area of practice and research. The issues of training and preparation, support and demands related to the event, and recovery and the social and organizational influences are assessed in depth. The assessment of occupational trauma is examined in the final chapter, with an emphasis on the need to carry out research which is longitudinal in nature and to explore a range of preventive strategies rarely discussed-for example, screening. This volume really does make a contribu- tion, both in terms of future research and strategies that organisations might adopt in coping with traumatic stress at work. It is up to date and clarifies many of the method- ological and occupational issues currently confronting the field of traumatic stress in an organizational context. It is not a cure all or a simple "do it yourself' guide to corpo- rate post-traumatic stress disorder, but a step in the right direction of an increasing problem among critical occupational groups. What is important for the health of employ- ees in any work environment, as this book reinforces time and time again, is to provide a creative and supportive organizational cul- ture. This can be done if we follow the sim- ple dictat of Kornhauser, over 30 years ago, in his book The mental health of the industrial worker. "Mental health is not so much a freedom from specific frustrations as it is an overall balanced relationship to the world, which permits a person to maintain a realis- tic, positive belief in himself and his pur- poseful activities. Insofar as his entire job and life situation facilitate and support such feelings of adequacy, inner security, and meaningfulness of his existence, it can be presumed that his mental health will tend to be good. What is important in a negative way is not any single characteristic of his sit- uation but everything that deprives the per- son of purpose and zest, that leaves him with negative feelings about himself, with anxi- eties, tensions, a sense of lostness, empti- ness, and futility." CARY L COOPER 144 o n A p ril 5 , 2 0 2 1 b y g u e st. P ro te cte d b y co p yrig h t. h ttp ://o e m .b m j.co m / O ccu p E n viro n M e d : first p u b lish e d a s 1 0 .1 1 3 6 /o e m .5 4 .2 .1 4 3 -b o n 1 F e b ru a ry 1 9 9 7 . D o w n lo a d e d fro m http://oem.bmj.com/