ABSTRACT
Humankind has known since antiquity that some substances possessed harmful properties. For instance, ancient peoples gradually learned which noxious plants to avoid eating; in effect, practicing the core principle of public health, prevention of disease and disability. Similarly, humankind learned to avoid venomous creatures whose bites could cause harmful health effects. The common factor between noxious plants and venomous creatures would over time become revealed to be chemical substances that possess toxic properties. In time, the study of chemical substances’ harmful properties would be called toxicology.
