Cadmium: (80 Handbook of Experimental Pharmacology)

The toxic properties of cadmium compounds have been well recognized in many species. There is little evidence to suggest a physiologic role for the metal. Rather, because of its long biologic half-life, cadmium acts as a cumulative poison, and even at quite low ambient concentrations, it can accumulate in mammals to values not insignificant in terms of critical toxic levels. The problem of cadmium toxicity has become especially important, as cadmium concentrations in the environment have begun to rise owing to a variety of human activities such as mining, the metallurgical industry, coal combustion, and the use of cadmium-containing fertilizers. It seemed appropriate, therefore, to assemble in one volume an up-to-date analysis of the mechanism of action of cadmium on biologic systems. Aspects of this field have repeatedly been reviewed in the past, and particular reference must be made to the volumes prepared by FRIBERG and collaborators from Sweden. Much outstanding work on cadmium has also been reported from Japan, and I am happy that investigators from both countries were able to contribute to the present volume. Obviously, this volume does not report a consensus by its contributors. The purpose of the work was to permit leading investigators in the field to present a critical review with sufficient documentation to support their interpretations and conclusions. A certain amount of overlap and disagreement between chapters was therefore unavoidable. The result, I hope, will be a useful state-of-the-art discussion.

Table of Contents:
1 The Estimation of Cadmium in Biological Samples.- A. Brief Survey of Cadmium Chemistry.- B. Analytic Methods for Cadmium.- References.- 2 Cadmium in the Environment and its Entry into Terrestrial Food Chain Crops.- A. Introduction.- B. Natural Occurence.- C. World Production.- D. Consumption.- E. Cadmium in Noncontaminated and Contaminated Soils.- F. Phytotoxic Effects of Cadmium.- G. Concentrations of Cadmium in Food Chain Crops.- H. Human Intake of Cadmium.- J. Methods to Control the Entry of Cadmium into Food Chain Crops.- K. Summary.- References.- 3 Absorption of Cadmium.- A. Introduction.- B. Routes of Exposure.- C. Mechanism of Intestinal Cd Absorption.- D. Control of Cd Absorption.- E. Summary.- References.- 4 The Chronic Toxicity of Cadmium: Influence of Environmental and Other Variables.- A. Introduction.- B. Environmental Pollution with Cadmium and Health Effects.- C. Renal Effects.- D. Skeletal Effects of Cadmium.- E. Blood Pressure, Cerebrovascular Disease, and Heart Disease.- F. Recovery from Cadmium-Induced Health Effects.- G. Chemical Forms of Cadmium in Food and Health Effects.- H. Elevated Sensitivity to Cadmium.- J. Metal Shift in Cadmium Intoxication.- K. Biologic Monitoring of Cadmium Exposure.- L. Estimation of Allowable Intake of Cadmium.- References.- 5 Effects of Cadmium Exposure in Humans.- A. Introduction.- B. Human Exposure to Cadmium.- C. Metabolism.- D. Acute Toxicity.- E. Chronic Toxicity.- References.- 6 The Nephropathy of Chronic Cadmium Poisoning.- A. Introduction.- B. Uptake, Storage, and Turnover of Cadmium in the Kidneys.- C. Effects on Tubular Function.- D. Effects on Glomerular Function.- E. Diagnosis.- F. Prognosis.- G. Prevention.- References.- 7 Cadmium and the Cardiovascular System.- A. Preface.- B. Historical Overview.- C. Actions of Cadmium on the Myocardium.- D. Vascular Actions of Cadmium.- E. The Cadmium Hypertension Controversy.- Appendix A.- Appendix B.- References.- 8 Role of Metallothionein in Cadmium Metabolism.- A. Introduction.- B. Historical Background and Chemistry of the Metallothioneins.- C. Determination of Metallothionein Concentrations in Mammalian Tissues.- D. Metallothionein and the Metabolism of Cadmium.- E. Metallothionein Synthesis in Relation to the Chronic Toxicity of Cadmium.- F. Metallothionein Synthesis in Relation to the Acute Toxicity of Cadmium.- G. Kidney Uptake, Metabolism and Toxicity of Exogenous Metallothionein.- H. Function of Metallothionein in the Transport of Cd from the Liver to the Kidney.- J. Normal Functions of Metallothionein and the Interactions of Cd with these Functions.- K. Function of Metallothionein in the Reproductive Toxicology of Cd: Role in Perinatal Development.- L. Metallothionein: A Limiting Factor in the Chelation Therapy of Cd Intoxication.- References.- 9 Immunotoxicity of Cadmium.- A. The Immune System.- B. Immunoassays.- C. Effects of Cadmium on Immune Responses.- D. Summary.- References.- 10 The Effect of Dietary Selenium on Cadmium Cardiotoxicity.- A. Introduction.- B. Cadmium and the Heart.- C. Selenium Deficiency and Cardiomyopathy.- D. Cadmium-Selenium Interactions.- E. Cadmium-Copper Interactions.- F. Cadmium-Metallothionein Studies.- G. Investigations into the Mechanism of Cadmium Cardiotoxicity.- H. Physiologic Studies.- J. Conclusions.- References.- 11 Cellular Resistance to Cadmium.- A. Introduction.- B. Cultured Cell Systems for Studying Cd Metabolism.- C. Role of Metallothionein in Cellular Cd Resistance.- D. Non-Metallothionein Mechanisms of Cellular Cd Resistance.- E. Models Describing Cd Metabolism and the Role ofMetallothionein and Other Factors in Resistance and Sensitivity.- F. Future Directions.- G. Summary.- References.