Because of the quantity and variety of chemicals used by the chemical process industries, chemical engineers must be knowledgeable about
• the way toxicants enter biological organisms,
• the way toxicants are eliminated from biological organisms,
• the effects of toxicants on biological organisms, and
• methods to prevent or reduce the entry of toxicants into biological organisms.
The first three areas are related to toxicology. The last area is essentially industrial hygiene, a topic considered in chapter 3.
Many years ago, toxicology was defined as the science of poisons. Unfortunately, the word poison could not be defined adequately. Paracelsus, an early investigator of toxicology during the 1500s, stated the problem: ...