A descriptive toxicologist is concerned directly with toxicity
testing, which provides information for safety evaluation and regulatory
requirements. The appropriate toxicity tests (as described
later in this chapter) in experimental animals are designed to yield
information that can be used to evaluate risks posed to humans and
the environment by exposure to specific chemicals. The concern
may be limited to effects on humans, as in the case of drugs and
food additives. Toxicologists in the chemical industry, however,
must be concerned not only with the risk posed by a company’s
chemicals (insecticides, herbicides, solvents, etc.) to humans but
also with potential effects on fish, birds, and plants, as well as other
factors that might disturb the balance of the ecosystem. Descriptive
toxicology studies provide important clues to a chemical’s
mechanism of action, and thus contribute to the development of
mechanistic toxicology through hypothesis generation. Such studies
are also a key component of risk assessments that are used by
regulatory toxicologists.