ACKNOWLEDGEMENTS PART 1 FISH CONSUMPTION AND METHYLMERCURY EXPOSURE IN THE AMAZON A. C. BARBOSA, A. M. GARCIA, J. R. DESOUZAI Mercurycontamination inhairofriverine 1-8 populations of Apiacas Reserve in the Brazilian Amazon E. D. BIDONE, Z. C. CASTILHOS, T. J. S. SANTOS, T. M. C. SOUZA and L. D. LACERDA I Fish contamination and human exposure to mercury in Tartarugalzinho River, Amapa State, Northern Amazon, Brazil. A screening approach 9-15 H. A. KEHRIG, O. MALM and H. AKAGI I Methylmercury in hair samples from different riverine groups, Amazon, Brazil 17-29 J. LEBEL, M. ROULET, D. MERGLER, M. LUCOTTE and F. LARRIBE I Fish diet and 31-44 mercury exposure in a riparian Amazonian population O. MALM. , J. R. D. GUIMARAES, M. B. CASTRO, W. R. BASTOS, J. P. VIANA, F. J. P. BRANCHES, E. G. SILVEIRA and W. C. PFEIFFER I Follow-up of mercury levels in fish, human hairand urine in the Madeira and Tapaj6s basins, Amazon, Brazil 45-51 PART 2 CHILD DEVELOPMENT AND LONG TERM EXPOSURE G. J. MYERS, P. W. DAVIDSON, C. COX, C. F. SHAMLAYE, O. CHOISY, E. CERNICHIARI, A. CHOI, J. SLOANE-REEVES, C. AXTELL, P. GAO and T. W. CLARKSON I The Seychelles child development study: Results and new directions through twenty-nine months 53-61 B. WHEATLEY, S. PARADIS, M. LASSONDE, M. -F. GIGUERE and S.

Carpal-tunnel and other entrapment syndromes are perhaps the most common work-related injuries currently reported. With this book, Vladimir Golovchinsky presents the first evidence of double-crush syndrome as a subgroup of these. To date the existence of double-crush syndrome has been a matter of debate. Dr. Golovchinsky presents a statistical analysis of substantial clinical material, which finds a cause-and-effect relationship between cervical or lumbar radiculopathy and peripheral entrapment in corresponding nerves, thus proving the existence of double-crush syndrome. This book will be invaluable to physicians performing EMG-NCV testing and to other healthcare professionals who encounter peripheral entrapment syndromes in their practices.

Excessive noise levels are generally acknowledged to have adverse effects on our environment. Studies indicate that excessive noise levels can cause fatigue in exposed individuals, lower efficiency and productivity, impaired speech communication, and hearing loss. Excessive noise is almost everywhere today - in the office, in schools, hospitals and other institutional facilities, in all classes of public buildings, and in our factories. INDUSTRIAL NOISE High noise levels in factories can make speech communication in the plant difficult and at times impossible. Foremen are often unable to hear warning shouts from co-workers. The problem of hearing loss due to excessive noise exposure is of particular concern to industry, and to the federal government. In the early 1970s, the United States Congress passed the Occupational Safety and Health Act (OSHA) which sets criteria for health hazards and established limits for noise exposure of industrial workers. The OSHA Noise Standard was amended in 1982 to require audiometric testing of all employees exposed to noise levels of 85 dB or above for eight hours. A NOISE IN COMMERCIAL AND INSTITUTIONAL BUILDINGS While noise levels in offices, stores, schools, and other commercial and institutional buildings seldom reach those encountered in many industrial environments, they often reach levels which are distracting to the occupants of such buildings. Impairment of speech communica tion among workers, or inversely the lack of speech privacy, are both deterrents to effiCiency and productivity and are detrimental to the occupants' comfort and sense of well-being."

The relationship between health and work is widely recognised as complex and multifaceted. In the context of an ageing population our ability to enable people with health issues to continue working is becoming more critical. This multi-disciplinary volume brings together original research from diverse disciplinary backgrounds investigating how we can define and operationalise a bio-psychosocial model of ill-health to improve work participation in middle and later life.

Almost 50 million persons visit another continent each year. It is mainly those 15-18 million travelers from industrialized nations who visit or reside in developing countries that are at increased health risk. To develop effective health protection advice, the health risks of travel and the benefits of prophylaxis (vaccines, new and old drugs, behaviour modification, etc.) should be assessed systematically. The purpose of this book is to improve the protection of the travelers' health by more effective and more uniform recommendations. It contains many data on recent research and represents the first comprehensive account on travel medicine for professionals.

As part of its "Programme for the prevention of health hazards caused by industrial substances", the Berufsge- nossenschaft der chemischen Industrie (BG Chemie, Em- ployment Accident Insurance Fund of the Chemical Indus- try) began in 1977 to investigate the toxicity of those chemicals which are widely used, have many different ap- plications and are suspected of being dangerous to health, in particular of having long-term effects. The in- vestigations consist of a literature search and - depending on the results - commissions of experimental studies. It is hoped by means of this testing to close gaps in our know- ledge and to increase the scientific validity of the required risk assessments. The results of the toxicological in- vestigations carried out by BG Chemie, and the resulting substance assessments have been published in German since 1987 in the form of 113 "Toxikologische Bewer- tungen" ("Toxicological Evaluations") up to now. In order to make this useful information internation- ally available, BG Chemie began in October 1990 to pub- lish them as a book series in English, of which the fifth vol- ume (containing 12 individual evaluations) is presented here. Therefore for 72 existing chemicals "Toxicological Evaluations" are available in English at the moment, a fur- ther 38 are in preparation and will be published soon.

"Toxicological Evaluations" are critically assessed data and recommendationsfor occupational safety officers, industrial hygienists, and human and animal toxicologists. They are compiled and constantly reviewed under internationally coordinated programms for establishing the risk potential of existing chemicals to prevent health hazards at the working place. Data for the following 61 chemicals have been published in the series: Acrylic acid, Benzalchloride, Benzotrichloride, Benzoylchloride, Benzylchloride, Bromoform, Butynediol, gamma-Butyrolactone, 4-Chloro-2-nitroaniline, Chloro acetic acid methyl ester, Chloroacetamide, o-Chlorobenzotrichloride, p-Chlorobenzotrichloride, o-Chlorobenzotrifluoride, m-Chlorobenzotrifluoride, Chloroformic acid ethyl ester, 4-Chlorophenyl isocyanate, m-Cresidine, N, N'-Di-sec.-butyl-p-phenylenediamine, 1,4-Diaminoanthraquinone, 1,4-Dicyanobutane, Dicyclopentadiene, Diethanolamine, Diethylcarbamoyl chloride, Diethyliene glycol, Diglycidyl ether, Diisopropanolamine, Dimethyl therephthalate, 2,4-Dinitromethylaniline, Ethylene thiourea, 2-Ethylhexanal, 2-Ethylhexanol, Hydrazobenzene, Isopropyl ethylene glycol ether, Maleic acid dimethyl ester, Manganese dioxide, 2-Mercaptobenzothiazole, Methoxyacetic acid, Methylbutadiene -1,3, 3-Methylbutanol-1, 2-Methylpropanol-1, 2-Methylpropene, Monochloroacetic acid, 1,5-Naphthalene diamine, 5-Nitro-2-aminotoluene, m-Nitroaniline, 5-Nitroanisidine, p-Nitrosophenol, Phenyl isocyanate, Phenylglycidyl ether, o-Phthalodinitrile, Propargyl alcohol Sodium hypochlorite, Therephthalic acid, Thiram, Tributyl phosphate, Triethanolamine, Triethylene tetramine, Trimethylphenyl-ammonium chloride, Trimethylquinone, Vinyl fluoride.

As part of its programme for the prevention of health hazards caused by industrial work substances, the Berufsgenossenschaft der chemischen Industrie (BG Chemie) began in 1977 to investigate the toxicity of those substances which are widely used, have many different applications and are suspected of being dangerous to health, in particular of having long-term effects on health. It is hoped by means of this testing to close gaps in our knowledge and to increase the scientific validity of the required risk assessments. The results of the toxicological investigations carried out by BG Chemie, and the resulting substance assessments have been published in West Ger many since 1987 in the form of "Toxicological Evaluations". In order to make this useful information internationally available, the second volume (containing individual evalua tions of 15 substances) is now being published in English. The first volume containing individual evaluations of 19 substances was published in October 1990. Because of the short time between publishing volumes 1 and 2, printing of the "Introduction" (consisting of a general overview of the programme, lists with names of people involved as well as substances under investigation was abandoned in volume 2. If there more detailed information is required, see volume 1 or contact BG Chemie at first hand. The publication of further individual evaluations and, if necessary, reassess ments of previously published evaluations is planned.

As part of its "Programme for the prevention of health haz- ards caused by industrial substances", the Berufsgenossen- schaft der chemischen Industrie (BG Chemie, Employment Accident Insurance Fund of the Chemical Industry) began in 1977 to investigate the toxicity of those chemicals which are widely used, have many different applications and are suspected of being dangerous to health, in particular of hav- ing long-term effects. The investigations consist of a litera- ture search and - depending on the results - commissions of experimental studies. It is hoped by means of this testing to close gaps in our knowledge and to increase the scientif- ic validity of the required risk assessments. The results of the toxicological investigations carried out by BG Chemie, and the resulting substance assessments have been published in German since 1987 in the form of 169 "Toxikologische Bewertungen" ("Toxicological Evaluations") up to now. In order to make this useful information internationally available, BG Chemie began in October 1990 to publish as a book series in English, of which the eighth volu- them me (containing 14 individual evaluations) is presented here. Therefore for 110 existing chemicals "Toxicological Evalua- tions" are available in English at the moment, a further 54 are in preparation and will be published soon.

Die Naturwissenschaften; Edward Arnold Co.; Research in Veterinary Science; Ltd.; Farm Mechanization and Buildings; Springer Verlag; The Ciba Foundation Ltd.; Journal of Agricultural Science; Journal of The Institute of Biology; The Lancet; The Reproduction and Fertility; Lea and Febiger; Physiological Society (G. B.); The Royal Masson et Cie, Paris; MacMillan Publishing Society; University of Chicago Press; Uni- Co., Inc.; National Academy of Science, versity of Rhodesia; Verhandlungen der U.S.; National Research Council of Canada; Deutschen Gesellschaft fur KreislautJorsch- Nature, London; North Holland Publishing ung; Waverly Press; and W. B. Saunders. Co.; Oxford University Press; Pergamon Press; Physiology and Behavior; Poultry D. L. INGRAM Science Association; Reinhold Publishing L. E. MOUNT Contents Preface Chapter 1 The Thermal Eml'ironment 1 Hot, Thermally Neutral, and Cold Environments 1 Development of Climatic Physiology 3 Physical Principles Chapter 2 Heat Exchange between Animal and Environment 5 Metabolic Heat and Its Dissipation 5 Body Temperature 6 Poikilotherm and Homeotherm 7 Heat Flow 8 Sensible Heat Transfer 9 Evaporative Heat Transfer 16 Calorimetry 21 Chapter 3 Metabolic Rate, Thermal Insolation, and the Assessment of Environment 24 Metabolic Rate and Heat Loss at High Temperatures 24 Thermal Conductance and Insulation 27 Evaporative Heat Loss 31 The Assessment of Thermal Environment 34 Responses of Different Species to High Temperatures 37 Physiological Mechanisms Chapter 4 Evaporative Heat Loss 39 Evaporative Loss from the Respiratory Tract 39 ix x Contents Conservation of Water Loss from the Respiratory 40 Tract in a Hot Dry Climate

More than 10 years ago, I had the chance to visit the university hospital in Munster, Germany. At the outpatient clinic there, I accidently met a young dermatologist who was devoted to the study of the quantification of irritated skin during his busy daily clinical work. I sensed immediately that this Dr. P. Frosch was conducting his research with the ideals and enthusiasm which were so familiar to me. Soon we found that we shared a similar past experience; we both had begun our careers in dermatological investigation with the same mentor. For me it was more than 25 years ago that I first met Dr. Kligman, Professor at the University of Pennsylvania in Philadelphia, USA. I reminisced that I had been greatly shocked by his initial question ''As a dermatologist, do you want to study living or dead skin?" because, at that time and even today, whenever we cannot collect enough information about the skin with the naked eye, it is invasively removed is common practice to histologically examine a skin sample that from living tissue. Many dermatologists still would never think of studying the living intact skin itself noninvasively with the aid of existing advanced technologies to assess its structural and functional properties. At that time Dr. Kligman intended to build up a system of evaluating the skin from various aspects, using methods that had been unduly neglected in the past and introducing various technological instruments.

The identification of occupational cancer risk factors and of carcinogens in the workplace is assuming increasing import ance in cancer epidemiology. This book, which contains the proceedings of a symposium held in Vancouver in June 1988, combines overviews by experts on substantive topics and methodologic issues of broad interest in occupational cancer epidemiology. Among the former are state of the art reviews emphasizing recent data and new and innovative analytic approaches. The substantive topics include discussion of cancer risks from exposure to complex organic mixtures, asbestos and man-made fibers, herbicides, radon, and electromagnetic fields. Risk assessment, exposure assessment, and analysis of occupa tional cohort studies are examples of the methodologic issues addressed. This book provides basic information and opens perspectives on new areas of research. In organizing our symposium we were greatly assisted by Betty Fata and Kim Rust of Venue West Conference Ltd. We appreciate the financial support received from the following: Cancer Control Agency of British Columbia Alcan Aluminium Ltd. National Health Research & Development Program Workers' Compensation Board of British Columbia Purdue Frederick Inc. Rhone-Poulenc Pharma Inc. London Drugs Ltd. Ciba-Geigy Canada Ltd. Bristol-Myers Pharmaceutical Group Schering Canada Inc. Hoffmann-La Roche Ltd. Sterling Drug Ltd. Parke-Davis Canada Inc. Beecham Laboratories Pfizer Canada Inc. Roussel Canada Inc."

As part of its "Programme for the prevention of health hazards cau- sed by industrial substances", the Berufsgenossenschaft der chemi- schen Industrie (BG Chemie, Employment Accident Insurance Fund of the Chemical Industry) began in 1977 to investigate the toxicity of those chemicals which are widely used, have many different applications and are suspected of being dangerous to health, in par- ticular of having long-term effects. The investigations consist of a literature search and - depending on the results - commissions of experimental studies. It is hoped by means of this testing to dose gaps in our knowledge and to increase the scientific validity of the required risk assessments. The results of the toxicological investiga- tions carried out by BG Chemie, and the resulting substance asses- sments have been published in German since 1987 in the form of 189 "Toxikologische Bewertungen" ("Toxicological Evaluations") up to now. In order to make this useful information internationally available, BG Chemie began in October 1990 to publish them as a book series in English, of which the tenth volume (containing 11 indivi- dual evaluations) is presented here. Therefore for 139 existing che- micals, "Toxicological Evaluations" are available in English at the moment, a further 54 are in preparation and will be published soon.

M. Pliftski Institute of Oceanography, GdaJisk University 46 Pilsudskiego Av. 81-378 Gdynia, Poland 2 The Baltic Sea with 366,000 km is only 0. 1% of the world's oceans but nevertheless, unique in many ways. The Baltic Sea is the largest area of brackish water in the world. As a formation of nature, it is a sea that in many ways resembles a lake. This makes its flora and fauna interesting and well adapted to the brackish water environment. The recent stage of biocoenosis composition is influenced by several features. Historically, during the last glaciation, when the Baltic was sometimes a huge marine bay and sometimes a large, freshwater lake, several ecosystems developed and were successively replaced. The flora and fauna composition of those previous biocoenosis was discovered from the geological layers corresponding to the Yoldic Sea, the Ancylus Lake and the Littorina Sea periods. Recently the marine influence has come from the North Sea water inflow, which greatly affects the salinity of the deep water. The freshwater influence comes from the fluvial water which gives the surface layer a lower salinity value. Salinity in the Baltic regions varies greatly - Gulf of Bothnia 2-4%0, the central Baltic proper 7-13%0, the Kattegat 15-300/00 in the surface water and 32- 34%0 in the bottom water, the Skagerrak 20-300/00 in the surface and 32-35%0 in the bottom water.

Considerable progress in understanding how inhaled minerals cause disease in man has been made in the past two decades. This is mostly due to the great amount of human, animal and cell multidisciplinary studies carried out on silica, asbestos and asbestiforms all around the world. Two previous NATO Workshops on "In Vitro Effects of Mineral Dusts on Cells", have been published in the NATO ASI Series (1985 and 1989). The present NATO-INSERM workshop has focused specifically on a group of silicates, named phyllosilicates because of their sheet structure, of which health related effects have been poorly and sporadically investigated. These silicates are presently largely used as filling materials (kaolin, talc, chlorite), insulating materials (vermiculite, micas), adsorbants (sepiolite, attapulgite) and in many other industrial applications. The estimated annual world production is presently 5.5 million tons of talc (1.8 million for Europe) and only in the United Kingdom about 3.5 million tons of kaolin.

As part of its programme for the prevention of health hazards caused by Industnal work substances, the Berufsgenossenschaft der chemischen Industrie (BG Chemie) began in 1977 to Investigate the toxicity of those substances which are widely used, have many different applications and are suspected of being dangerous to health, in particular those having long-term effects on health. The investigations consist of a literature search and - depending on the results - commissions of experimental studies. It is hoped by means of this testing to close gaps In our knowledge and to increase the scientific validity of the required risk assessments. The results of the toxicologi cal investigations carried out by BG Chemle, and the result ing substance assessments have been published In German since 1987 In the form of "Toxikologische Bewer tungen" ("Toxicological Evaluations"). In order to make this useful Information internationally available, the third volume (containing Individual evalua tions of 13 substances) of the senes IS now being published In English, the first volume of which was published in October 1990. Because of the short time between publish ing volume 1,2 and 3, printing of the "Introduction" (consist Ing of a general overview of the programme, lists with names of people involved as well as substances under Investigation) was abandoned In volumes 2 and 3. If more detailed information is required, see volume 1 or contact BG Chemie at first hand. The publication of further individual evaluations and, if necessary, reassessments of previously published evalua tions is planned.

"Musculoskeletal, Sports, and Occupational Medicine: Rehabilitation Medicine Quick Reference" provides the core knowledge the busy practitioner needs to deliver top-notch rehabilitative care to patients with musculoskeletal, sports, or occupational injuries. Covering 107 alphabetically arranged topics from Achilles Tendinopathy to Whiplash, this nuts and bolts resource is designed to provide concise and accurate information. The book begins with a template for evaluating a patient with musculoskeletal injury, and covers the full gamut of conditions and sequelae commonly seen by practitioners dealing with bone, joint, and soft tissue problems in athletes, injured workers, and individuals of any age with musculoskeletal issues.

Every entry is standardized for quick look-up in the office or clinic, and features description, etiology, risk factors, clinical features, natural history, diagnosis, red flags, treatment, prognosis, helpful hints and suggested readings.

Every entry is standardized for quick look-up in the office or clinic, and features description, etiology, risk factors, clinical features, natural history, diagnosis, red flags, treatment, prognosis, helpful hints, and suggested readings. All "Rehabilitation Medicine Quick Reference"titles offer: Consistent Approach and Organization: at-a-glance outline format allows readers to find the facts quickly Concise Coverage: of must-know information broken down into easy-to-locate topics Fast Answers to Clinical Questions: diagnostic and management criteria for problems commonly encountered in daily practice Hands-on Practical Guidance: for all types of interventions and therapies Multi-Specialty Perspective: ensures that issues of relevance to all rehabilitation team members are addressed

The mastery of a variety of biomedical They avoided the self-destruction and dis techniques has led our society to the solu ease that can so readily follow the escalation tion of the problems in environmental con of social disorder in an isolated colony. By trol imposed by space flight. By an unparal following a "code of civility" that may be as leled social cooperative effort, man has much a part of man's biologic inheritance as launched himself successfully on the path of his speech, they established cultures in interplanetary exploration and space travel. which power was exercised with sufficient By a like synthesis of knowledge available to respect to establish a consensus. They fol him, Stone Age man kept a foothold on tiny lowed revered cultural canons, using an Pacific atolls for the better part of a thousand accumulation of rational empiric data from years, despite obliterating hurricanes and social experience to modify and control the inherited biogrammar. This we often fail to limited resources. By combining empiric do. There is growing evidence that it is phys navigational skills, such as the sighting of stars with intuitive feeling for ocean swells iologically possible for the left hemisphere of and other subtle cues, tiny populations were the brain, which deals with logic and lan maintained in communication over vast dis guage, to be cut off from the right hemi tances."

International cooperation on the health of seafarers began many years ago. As early as 1921, an international convention regarding this matter was presented to govern ments of maritime countries for ratification. The First World Health Assembly, in 1948, recommended that WHO should establish, with the International Labour Of fice, a Joint Committee on the hygiene of seafarers. The first session of this Com mittee, held in 1949, defined the problems affecting the health of seamen and made a number of recommendations. In the opinion of this Joint Committee, the health of seamen called for interna tional attention for a nu mb er of reasons. By the nature of his work, the seafarer is obliged to travel from country to country and is exposed to great variations of cli mate and also to any disease that may be prevalent in the port of call. He may there fore become a carrier of disease, so that the protection of his health is of importance not only to himself and the other members of the crew but also to the populations of other countries he visits. Yet, on account ofthe nature ofhis employment, it is diffi cult to provide the seafarer with the same standard of health care that is gene rally available to other sections of the population."

In recent years the field of contact dermatitis has increased greatly in importance in dermatology. The variety of exogenous, environmental ly caused dermatoses has undoubtedly expanded over the past few de cades with the increasing number of potentially toxic chemicals, the changes in lifestyle, and the greater life expectancy in industrialized societies. The value of international cooperation in this field has long been realized and acted upon by the International Contact Dermatitis Re search Group (ICDRG). By 1975 the international journal Contact Dermatitis had been founded under the editorship of C. D. Calnan. Thanks largely to the ICDRG and Contact Dermatitis, there were, by 1986, enough additional dermatologists and scientists with a special interest in this area to form the European Environmental and Contact Dermatitis Research Group (EECDRG). Within 2 years they had in stituted the European Society of Contact Dermatitis (ESCD) as an in ternational forum for researchers in the field. The EECDRG decided to hold a symposium in Heidelberg in May 1988, an initiative supported by the ICDRG, and on this occasion the new ESCD held its inaugural session. The Society already has over 200 members and most national contact dermatitis research groups in Europe are already represented; new members are of course welcome. Subgroups and working committees have been formed to address var ious topics including the standardization of patch testing, photoder matology, and bioengineering."

Infant Feeding is about a controversy which fascinated the medical and scientific world, as well as national and international health authorities, politicians, religious groups and consumer organisations, for more than 11 years. It often disturbed public opinion, being concerned, as it is, with nothing less than the life and death of babies. The infant food industry was directly accused of having caused a decline in breast-feeding through the inappropriate marketing of breast milk substitutes. The problem was said to be particularly acute in poor under-developed communities, because illiterate mothers were unable to understand instructions for its use, water was often contaminated and, in order to "stretch" an admittedly expensive product, it was over-diluted. The inevitable result, said the critics of industry, was malnutrition, gastroenteritis and increased infant mortality. These were very serious charges against companies which had until then been generally considered to provide an important contribution to medical progress and child health. One company was to be particularly singled out: Nestle SA, the Swiss multinational. Perhaps it became the target because it was the longest establishment, and served well as a symbol of the whole industry. It is a story which is full of confrontations, intrigue and passionately-held opinions, based, nevertheless, on a sizeable body of medical science. After countless twists and turns, it has some sort of "happy ending". Yet a great deal remains to be said, as will be seen throughout the book.

Toxicological Evaluations are critically assessed data and recommendations for occupational safety officers, industrial hygienists, and human and animal toxicologists. They are compiled and constantly reviewed under internationally coordinated programs for establishing the risk potential of existing chemicals to prevent health hazards at the working place. In Volume 11, data for the following chemicals are published: o-Phthalodinitrile, Dimethylaminopropionitrile, Anthraquinone, Triisobutylphosphate, 4-Nitro-4'-aminodiphenylamine-2-sulfonic acid, 2,5-Dimethoxy-4-chloreanilino, Antimony-(III)-chloride, Antimony-(V)-chloride, Antimony-(V)-oxide, N, N-Dicyclohexyl-2-benzothiazolesulfenamide, Ethenesulfonic acid, sodium salt.

Toxicological Evaluations are critically assessed data and recommendations for occupational safety officers, industrial hygienists, and human and animal toxicologists. They are compiled and constantly reviewed under internationally coordinated programs for establishing the risk potential of existing chemicals to prevent health hazards at the working place. In Volume 13, data for the following chemicals are published: Benzyl chloride, Triethylenediamine, 2-Amino-6-methoxybenzothiazol, Fluorobenzene, alpha-Naphthylamine, Triethylphosphite, Diethylphosphite, Diphenyl-2-ethylhexyl phosphate, alpha-Chlorpropionic acid and sodium-alpha-chloropropionate, Zinc ethylphenyl dithiocarbamate, Dimethoxy thiophosphonyl chloride, p-Chlorbenzotrifluoride.

My introduction to the fascinating phenomena associated with detonation waves came through appointments as an external fellow at the Department of Physics, University College of Wales, and at the Department of Mechanical Engineering, University of Leeds. Very special thanks for his accurate guidance through the large body of information on gaseous detonations are due to Professor D. H. Edwards of University College of Wales. Indeed, the onerous task of concisely enumerating the key features of unidimensional theories of detonations was undertaken by him, and Chapter 2 is based on his initial draft. When the text strays to the use of we, it is a deserved acknow ledgement of his contribution. Again, I should like to thank Professor D. Bradley of Leeds University for his enthusiastic encouragement of my efforts at developing a model of the composition limits of detonability through a relationship between run-up distance and composition of the mixture. The text has been prepared in the context of these fellowships, and I am grateful to the Central Electricity Generating Board for its permission to accept these appointments."

To be asked to prepare a second edition of a book is heartening for any author or editor. Apart from the opportunity to make the corrections and amendments which are inevitable in a practical manual there is also the possibility to make additions which enhance its usefulness. Above all a further edition usually means that the book has been found to be accept able to a large number of readers and has fulfilled a need. This is indeed the case with Offshore Medicine, which in its description of the medical aspects of offshore work has provided a unique guide to the occupational health of a new industry. The rapid development of offshore exploration for gas and oil which began in the 1960s created a whole new range of related industries. Most attention was focused on the problems of deep diving in the North Sea because of the great expansion of the diving industry, its technological advances and the high mortality of divers in the early years. Diving, however, is only a fraction of the total endeavour concerned with the offshore industry. The much larger population of workers offshore who man the rigs and barges, the toolpushers, helicop ter pilots, crane drivers, scaffolders and roustabouts, geologists and so on, so sympathetically described by A. Alvarez in his recent book Off shore, A North Sea Journey, and the harsh and difficult conditions in which they often have to work are sometimes forgotten."