A biological endpoint is a direct marker of disease progression - e.g. disease symptoms or death - used to describe a health effect (or a probability of that health effect) resulting from exposure to a chemical. More: Exposure to a particular chemical may lead to a series of endpoints. The most sensitive endpoint (critical endpoint) is the one that occurs at the lowest exposure level. The derivation of a tolerable daily intake (TDI) or an acceptable daily intake (ADI) is based on the NOAEL (no observed adverse effect level) of the most sensitive endpoint and will also ensure protection against all other adverse effects.
