ABSTRACT
ClassiÞcation of chemical agents is a daunting task, considering the vast number and complexity of chemical compounds in the public domain. With the variety of chemicals and drugs available, and their varied pharmacological and toxicological effects, an agent may Þnd itself listed in several different categories. Even compounds with similar structures or pharmacological actions may be alternatively grouped according to their toxicological activity or physical state. The following outline of the classiÞcation systems is generally accepted for understanding the complex nature of toxins. The mechanisms of toxicity will be discussed in subsequent chapters.
