Japanese encephalitis and West Nile viruses are members of the Japanese encephalitis serological group of the genus Flavivirus and therefore closely related genetically and antigenically. They share a number of properties, including the use of birds as their major wildlife maintenance host and Culicine mosquitoes for transmission, and they are both associated with severe human disease, as well as fatal infections in horses.
The emergence of these two viruses, and their well-established propensity to colonise new areas, make it timely to re-examine their ecology, biology, molecular structure, replication and epidemiology, and these therefore provide the focus of this volume.

A good number of misconceptions are currently circulating on the effects of non-ionizing radiations on our health, which can lead to an oversimplification of the issue, to potentially dangerous assumptions or to misleading data analysis. Health effects may be exaggerated, or on the contrary underplayed. The authors of this work (doctors, engineers and researchers) have endeavored to supply validated and easily understandable scientific information on the electromagnetic fields and their biological and health effects. After a general review of the physics of the waves and a presentation of non-ionizing radiations, the authors review the main emission sources encountered in our daily environment. They summarize simply but as accurately as possible the current knowledge on their biological effects.
The safety limits recommended by international organizations are presented for the different frequency ranges. This book is intended for doctors, teachers, scientists, students, policy makers and anyone else interested in a deeper understanding of the health effects of electromagnetic fields. Intended to serve a broad readership, everyone will approach it according to their respective level of curiosity and knowledge. It is neither an exhaustive inventory of all the studies made to date, nor a survey text focusing only on some chosen studies. Nor is the objective to present all the sources of non-ionizing radiations. Interested readers will be given the opportunity to broaden their knowledge, also by consulting the selected bibliography presented by the authors at the end of each chapter.

The probability for exposure to damaging radiation, toxic chemicals in the environment and adverse biological agents has increased exponentially today. The more frequent and faster travel that we experience today also escalates the risk of contraction and transmission of potentially deadly infections. This has created a very real and escalating risk for injuries and deaths. This is accentuated in the military and medical staff that is more frequently exposed to radiological, chemical, and biological agents in their normal working environment. Understanding the mechanisms whereby these toxic agents inflict damage to our bodies is essential to prepare us for these challenges. Much of the damage is inflicted through the generation of free radicals and non-radical oxidants which then act through oxidative mechanisms to injury the body. This volume will discuss the damage caused by these radiological, chemical, and biological environmental stressors, the mechanisms through which the damage can occur and the novel strategies that can be used to reduce the injury inflicted by these toxic compounds. Using basic and clinical research approaches, the contents of this book discuss new ideas for the development of bioactive products and environmental approaches to lessen or negate the biological damage inflicted by these noxious compounds.

Seasonal patterns have been found in a remarkable range of health conditions, including birth defects, respiratory infections and cardiovascular disease. Accurately estimating the size and timing of seasonal peaks in disease incidence is an aid to understanding the causes and possibly to developing interventions. With global warming increasing the intensity of seasonal weather patterns around the world, a review of the methods for estimating seasonal effects on health is timely.

This is the first book on statistical methods for seasonal data written for a health audience. It describes methods for a range of outcomes (including continuous, count and binomial data) and demonstrates appropriate techniques for summarising and modelling these data. It has a practical focus and uses interesting examples to motivate and illustrate the methods. The statistical procedures and example data sets are available in an R package called season ."

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.

This highly topical book provides an in-depth account of the South Asian experience with the deadly disease that has held this region hostage for millennia. The book touches specifically on the resurgence of malaria experienced in the second half of the twentieth century, which occurred just a few years after malaria was thought to have been virtually eradicated from the region. The progress of this reappearance across space and time, as well as its causes and consequences, are discussed. The book also covers past, present and future ways to curb, control and ultimately, conquer malaria. As malaria continues to ravage the developing world, even in today s age of science, this is a particularly relevant book, especially as most studies analyze the problem in Africa, the continent that bears the brunt of this disease. Here, the authors call attention to challenges in South Asia, home to an immense at-risk population. The chapters in this book use a range of conceptual frameworks, quantitative analyses and descriptive aapproaches, finding that malaria is not just a complex disease driven by highly adaptive agents and vectors thriving in particular ecologies, but also a social concern deeply related to the region s cultural traditions, financial and developmental shortfalls, and inexorably related to political will.

The book comprehensively deals with all aspects of the malaria situation in South Asia, and is invaluable to upper level students as well as emerging and established scholars in the fields of medical geography and epidemiology, Asian studies and development studies."

In a new era of global health diplomacy, the most important tool for decision-making is negotiation. Globalization is binding countries, issues and people together as never before. In the domain of public health, traditional international concerns like the spread of infectious diseases have been joined by new concerns and challenges in managing the health impacts of trade and intellectual property rights, and by new opportunities to create effective global public health agreements and programs. To address the major health crises of today and to prevent or mitigate them in the future, countries must seek collective agreement and action within and across their borders. However, the world of international negotiation is not the world in which health decision-makers reside or are most comfortable. The goal of this guide is to provide health policy-makers with practical information and negotiation tools, to help them create better international health agreements and programs. "This is the best book I know to help health professionals develop the negotiation skills necessary to meet the challenges of global health diplomacy. It is filled with wise advice and invaluable tools for success." Professor Jeswald W. Salacuse, The Fletcher School of Law and Diplomacy, Tufts University

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.

This series is dedicated to serving the growing community of scholars and practitioners concerned with the principles and applications of environmental management. Each volume is a thorough treatment of a specific topic of importance for proper management practices. A fundamental objective of these books is to help the reader discern and implement man's stewardship of our environment and the world's renewable resources. For we must strive to understand the relation ship between man and nature, act to bring harmony to it, and nurture an environment that is both stable and productive. These objectives have often eluded us because the pursuit of other individual and societal goals has diverted us from a course of living in balance with the environment. At times, therefore, the environmental manager may have to exert restrictive control, which is usually best applied to man, not nature. Attempts to alter or harness nature have often failed or backfired, as exemplified by the results of imprudent use of herbicides, fertilizers, water, and other agents. Each book in this series will shed light on the fundamental and applied aspects of environmental management. It is hoped that each will help solve a practical and serious environmental problem."

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.

ENVIRONMENTAL HYGIENE III deals with the detection and evaluation of environmental pollutants as well as with their relevance to human health. Environmental components are important determinants of the health status of groups at risk and of the general population. The main objective is the early detection and identification of hazardous substances by physical, chemical and biological methods, risk assessment andprotection of human health. Faced with these problems the volume gives an overview on the mulifaceted aspects of environmental hygiene and medicine. Contributions include basic and innovative approaches in the fields of - Experimental cell biology - Cytotoxicity testing - Mutagenicity and carcinogenicity studies - Inhalation toxicity - Human exposure monitoring - Epidemiology - Important harzardous agents - Environmental control, prevention and legislation.

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."

The protection of human health and food and fiber resources against the ravages of pests of many sorts is a continuous struggle by all people in the world. The use of chemical pesticides as an aid in this struggle is now also global. These chemicals are deliberately added to the environment for the purpose of killing or injuring some form of life. Because pesticides are generally less selectively toxic than would be desired, non-target species, including humans, must be protected from injury by these chemicals. This can only be achieved by thorough understanding of the comparative toxicology of these compounds, and by minimizing human (and other desirable species) exposure. The latter can only be achieved by sound regulatory policies that utilize scientific principles and data, properly tempered by both gaps in that data and sociologic and economic considerations. This book contains the proceedings of the NATO Advanced Study Institute on "Toxicology of Pesticides: Experimental, Clinical and Regulatory Perspectives" held in Riva del Garda on October 6-15, 1986. This NATO-ASI has been promoted by the School of Public Health and Community Medicine, University of Washington at Seattle, by the Institute of Pharmacological Sciences, University of Milano and by the Giovanni Lorenzini Foundation, and has been sponsored by both the Society of Toxicology (USA) and the Italian Society of Toxicology.

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.

A. AULICIEMS Living organisms respond to atmospheric variability and variation, and over time morphological and process differentiations occur both within individuals and the species, as well as in the environment itself. In systems language, the concern is with the atmospheric process-response system of energy and matter flows within the biosphere. The study of such interactions between living organ isms and the atmospheric environment falls within the field of bioclimatology, alternatively referred to as biometeorology. Amongst the more readily recognizable study areas under the bioclimatolog that investigate the effects of atmospheric variation and ical umbrella are those variability upon 1. Terrestrial and aquatic ecology (zoological, botanical and ethological), natural resource production and management (including silviculture, agri culture, horticulture, and grassland, wetland, and marine systems). 2. Stress, morbidity and mortality in animals and humans (including physiolog ical and psychological adaptations). 3. The built environment (all aspects of planning, urban design, and architec ture). 4. Economic systems and social activities (including organizational, individual, and group behavior and management). In addition, bioclimatology is very much concerned with the feedback loop, that is both 5. The inadvertent modification of the atmosphere by living systems, especially human, i.e., studies of pollution, changes to atmospheric amenity, and the processes of deterioration of landscape (deforestation and desertification), and 6. The advertent modifications of natural energy and matter flows within urban areas and indoor climate constructions."

The purpose of this book is to investigate the suitability and applicability of available methods for analyzing the human and ecological risks involved in the release of genetically-modified microorganisms. Main topics include: - risk analysis and assessment; approach to safety assurance; - inventory of available scientific risk assessment methods for biotechnology; - identification of methodology gaps and research needs in biology, ecology or other disciplines; - development of a general framework to guide future biotechnology risk assessment efforts; - international regulatory activities.