Figure 1.

Schematic of the Key Events Dose-Response Framework. The Key Events Dose-Response Framework organizes information on the multiple biological events that occur between an initial dose and the specified effect of concern. Events are indicated generically; but a given pathway may have several kinetic and dynamic events, and may include events that are reversible. In theory, each event may be characterized by its dose and its outcome. Various mechanisms may be available at some events to respond to conditions caused by the agent.