Substantial progress has been made during the past three decades in the development of a variety of chemical means to control insect pests. A large number of highly effective insecticides have been developed, and many of them have contributed to a great extent to increasing agricultural productivity and eradicating diseases transmitted by vectors. However, contamination of our environment caused by various pesticides has become a serious problem, and various attempts have been made to develop newer methods of con trolling insect pests. One of the approaches is to develop newer insecticides which cause less contamination of the environment without losing their insecticidal potencies. Another approach, among other things, is to utilize pheromones to control certain species of insects. No matter what approach one may choose, it is imperative to understand the mechanism of action of pesticides for efficient development and utilization of these chemicals. One important feature common to most insecticides and pheromones is their inter action with the nervous system which is the main target site. Thus the mechanisms of action of these chemicals on the nervous system represent one of the most critical aspects in pesticide toxicology. In comparison to the chemical and biochemical studies dealing with the metabolism of various pesticides, the study of neurotoxicology has lagged behind to a considerable extent for various reasons. Technical complications involved in neuroto- co logical experiments appear to be one of the contributing factors."

Knowledge of the mechanism of action of drugs at cellular, subcellular, or molecular levels is of vital importance not only in giving the basis of inter pretation of the systemic action of drugs but also in improving existing drugs; in designing new forms of drugs; and in giving the basis of therapeutic applications. Classical pharmacology, concerning the action of drugs at integrated levels, does not necessarily give sufficient information as to the mechanism of action of drugs. A variety of sophisticated concepts utilizing the methods of physics, chemistry, biophysics, biochemistry, and physiology must be synthesized to understand the mechanism of action. Only since the last decade, however, have these techniques been fully applied to pharma cological investigations. It is of utmost importance to realize that a new dimension of pharmacological research has indeed emerged as a result of such a multidisciplinary approach; this approach is encompassed in general and cellular pharmacology. Such recent studies of drug actions have led to a number of important findings. Certain chemicals and drugs were found to possess highly specific actions on cellular functions, so that they are widely being used as powerful tools for the study of a variety of physiological and pharmacological prob lems. Our knowledge of the cellular mechanisms of drug action has provided the basis for interpreting the systemic effects of the drugs and insight into the molecular mechanism involved.

This volume offers the most comprehensive presentation available on metal toxicology. It discusses not only metals but also the toxic endpoints, such as neurotoxicity, renal toxicity, and cancer induction. Chapters are written by experts in their respective fields, focusing on carcinogenesis and human exposures and highlighting the major aspects and issues of toxicity in general.