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Exploration for uranium ore deposits
114 similar structures in spite of their mechanical instability and possible penetration by ground waters. The results of current research, which are described in the proceedings of this symposium, illustrate that considerable information is now available to provide some degree of containment of radioactive waste; with developments in technology, it is premature to relax and consider the problem potentially solved until we can arrive at firmer conclusions for the management and disposal of long-lived radioactive wastes which are likely to outlive the lifespan of man. Meanwhile, research into these matters clearly stimulates interest in many disciplines with particular xgference to the consequences of any defined method of disposal in relation to environmental changes which may take place, hence the need to improve predictions for such events as earthquakes, climatic change and matters concerned with the stability of the earths crust and oceans at sites for terminal storage.
Plymouth (England)
E. I. Hamilton
Explorationfor Uranium Ore Deposits, International Atomic Energy Agency, Vienna, 1976, 807 pp., price: US $ 49.00. Today the known exploitable resources of uranium ore amount to about 1.1 million tonnes; current nuclear power requirements use some 18,000 tonnes each year which is expected to reach about 100,000 tonnes by about 1985. Over the next thirty years we can expect to see an increase in the use of nuclear power as a source of raw electricity and the conservation of fossil fuels for the manufacture of useful by-products. Uranium is therefore very likely to be an important consideration in the future economy of many countries. At present the major resources of uranium are to be found in Australia, Canada, S. Africa, the United States of America and Russia. In order to determine total world resources of uranium and their distribution for a wide range of ore types, considerable attention is being directed towards identifying anomalies and evaluating their economic importance. It has become essential to understand more fully the behaviour of uranium in different types of environments and develgp suitable predictive techniques for identifying buried deposits. This volume is very timely and presents an admirable account of the deployment of existing techniques and new possibilities, such as delayed neutron counting, pulsed neutrons and the fission track method. Attention is focussed on the need to use several methods of exploration involving geochemistry, geophysics and satellite photographic methods. Several case histories are described for the evaluation of ore deposits and it is emphasised that further deposits may be present in rocks which at the moment are not associated with uranium because of lack of knowledge of the manner in which this element migrates through crustal rocks. Future needs for research are outlined and the volume ends with reports from various working parties which provide a summary of the main topics discussed in this very useful symposium. The 1973 oil-crisis stimulated research into alternative
115 sources of energy; this volume illustrates how the tools of modern technology can be applied in the exploration of one element, namely uranium.
Plymouth (England)
E.I. Hamilton
IARC Monographs on the Evaluation of Carcinogenic Risks of Chemicals to Man: Some Carbamates, Thiocarbamates and Carbazides, Vol. 12, World Health Organization, Geneva, 1976, 282 pp., price: Sw. fr. 34.00; US $14.00. In continuing efforts to evaluate the carcinogenic risks of chemicals to man, IARC devotes this volume to a group of 24 carbamate esters, most of which are used as insecticides, fungicides, or herbicides. The working group has summarized and critically evaluated the published animal studies on the carcinogenicity of each of the selected chemicals, noting, in many cases, the inadequacies of the published data in terms of evaluation of carcinogenicity, and a lack of clinical and epidemiological studies. Additionally, other relevant biological and biochemical data have also been summarized (but without any evaluation) for most of the chemicals. Sections on chemical and physical properties of chemicals, and on their production, use and analysis, provide valuable information. The animal carcinogenicity data in case of 19 out of 24 chemicals is based, at least partly, on studies by Innes et al. (1969), deficiencies of which have been adequately scored (p. 24, and under individual sections of monographs); however, it should also be pointed out that the number of animals tested was relatively small, cause of death of animals prior to 78 weeks was not given, and the treatment schedule (feeding of chemicals by stomach tube to neonates, and in diet ad libitum to adults) is complicated because neonates are often considered to be more susceptible to carcinogenic action than the adults. Overall, this volume, like the preceding 11 volumes, should make a good source of reference for the published literature on the selected compounds' andis recommended for the researchers in this and related areas. Specific comments are as follows: 1. Considering the lack of definitive data on the carcinogenicity of most of the selected chemicals, it would be more appropriate to state (under sections 4.1 of the concerned monographs) whether incidence of tumors in treated animals was (or was not) significantly higher than in controls (see, e.g., p. 47, 64, 126, 156, 164, etc.). A more consistent format, incorporating significance limits, is recommended for evaluation. 2. In most monographs, description of the frequency of treatment under Section 4.1, is inadequate and misleading: chronic oral administration will be more appropriate than "oral administration". Similarly, the frequency of intraperitoneal and subcutaneous administration should be clarified; it becomes quite confusing especially where studies with different treatment schedules are discussed (see, e.g., p. 197, Section 4.1).
Plymouth (England)
E. I. Hamilton
Explorationfor Uranium Ore Deposits, International Atomic Energy Agency, Vienna, 1976, 807 pp., price: US $ 49.00. Today the known exploitable resources of uranium ore amount to about 1.1 million tonnes; current nuclear power requirements use some 18,000 tonnes each year which is expected to reach about 100,000 tonnes by about 1985. Over the next thirty years we can expect to see an increase in the use of nuclear power as a source of raw electricity and the conservation of fossil fuels for the manufacture of useful by-products. Uranium is therefore very likely to be an important consideration in the future economy of many countries. At present the major resources of uranium are to be found in Australia, Canada, S. Africa, the United States of America and Russia. In order to determine total world resources of uranium and their distribution for a wide range of ore types, considerable attention is being directed towards identifying anomalies and evaluating their economic importance. It has become essential to understand more fully the behaviour of uranium in different types of environments and develgp suitable predictive techniques for identifying buried deposits. This volume is very timely and presents an admirable account of the deployment of existing techniques and new possibilities, such as delayed neutron counting, pulsed neutrons and the fission track method. Attention is focussed on the need to use several methods of exploration involving geochemistry, geophysics and satellite photographic methods. Several case histories are described for the evaluation of ore deposits and it is emphasised that further deposits may be present in rocks which at the moment are not associated with uranium because of lack of knowledge of the manner in which this element migrates through crustal rocks. Future needs for research are outlined and the volume ends with reports from various working parties which provide a summary of the main topics discussed in this very useful symposium. The 1973 oil-crisis stimulated research into alternative
115 sources of energy; this volume illustrates how the tools of modern technology can be applied in the exploration of one element, namely uranium.
Plymouth (England)
E.I. Hamilton
IARC Monographs on the Evaluation of Carcinogenic Risks of Chemicals to Man: Some Carbamates, Thiocarbamates and Carbazides, Vol. 12, World Health Organization, Geneva, 1976, 282 pp., price: Sw. fr. 34.00; US $14.00. In continuing efforts to evaluate the carcinogenic risks of chemicals to man, IARC devotes this volume to a group of 24 carbamate esters, most of which are used as insecticides, fungicides, or herbicides. The working group has summarized and critically evaluated the published animal studies on the carcinogenicity of each of the selected chemicals, noting, in many cases, the inadequacies of the published data in terms of evaluation of carcinogenicity, and a lack of clinical and epidemiological studies. Additionally, other relevant biological and biochemical data have also been summarized (but without any evaluation) for most of the chemicals. Sections on chemical and physical properties of chemicals, and on their production, use and analysis, provide valuable information. The animal carcinogenicity data in case of 19 out of 24 chemicals is based, at least partly, on studies by Innes et al. (1969), deficiencies of which have been adequately scored (p. 24, and under individual sections of monographs); however, it should also be pointed out that the number of animals tested was relatively small, cause of death of animals prior to 78 weeks was not given, and the treatment schedule (feeding of chemicals by stomach tube to neonates, and in diet ad libitum to adults) is complicated because neonates are often considered to be more susceptible to carcinogenic action than the adults. Overall, this volume, like the preceding 11 volumes, should make a good source of reference for the published literature on the selected compounds' andis recommended for the researchers in this and related areas. Specific comments are as follows: 1. Considering the lack of definitive data on the carcinogenicity of most of the selected chemicals, it would be more appropriate to state (under sections 4.1 of the concerned monographs) whether incidence of tumors in treated animals was (or was not) significantly higher than in controls (see, e.g., p. 47, 64, 126, 156, 164, etc.). A more consistent format, incorporating significance limits, is recommended for evaluation. 2. In most monographs, description of the frequency of treatment under Section 4.1, is inadequate and misleading: chronic oral administration will be more appropriate than "oral administration". Similarly, the frequency of intraperitoneal and subcutaneous administration should be clarified; it becomes quite confusing especially where studies with different treatment schedules are discussed (see, e.g., p. 197, Section 4.1).