5-1 EXPOSURE
Chapter 4 covered the release of hazardous waste constituents and their fate in the environment.
The series of steps starting with a release of waste constituents and . concluding with the interface with
a human body is referred to as an exposure pathway. Gaining entry into the body is referred to by
toxicologists as the exposure route. There are three exposure routes by which environmental
contaminants may enter the body: inhalation (respiratory tract), ingestion (gastrointestinal tract), and
dermal contact (skin) (see Figure 5-1).