Toxicology, defined Toxin

Environmental toxicology is defined as the study of the fate and effects of chemicals in the environment. Although this definition would encompass toxic chemicals naturally found in the environment (i.e., animal venom, microbial and plant toxins), environmental toxicology is typically associated with the study of environmental chemicals of anthropogenic origin. Environmental toxicology can be divided into two subcategories ... 

This text provides an excellent reference for clinicians in emergency and occupational health settings. Medical toxicology is defined here as poisoning by overdose of medication and exposure to chemicals and toxins not ordinarily used therapeutically. This is a good companion work to Dreisbach. Also available on CD-ROM and via online subscription. 

Our view of toxic chemicals is governed by the edict of Paracelsus, a sixteenth-century physician. For many toxins, perhaps the vast majority, the dose does make the poison. This first law of toxicology has driven a great deal of research and safety regulation. In the world of modern poisons, many of the interactions between the molecule and the organism are defined by this simple yet elegant relationship. 

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