NOEL (No-Observed-Effect Level)

Definition

The NOEL is the highest tested dose or exposure level at which no effects, adverse or otherwise, are observed in any individuals during a study.

Related terms

LOEL (Lowest-Observed-Effect Level): The LOEL is the lowest tested dose or exposure level at which any effect, adverse or otherwise, is observed during a study.

Threshold Limit Value (TLV): TLV represents the maximum concentration of a substance to which workers can be exposed without experiencing adverse health effects over their working lifetime.

Reference Dose (RfD): RfD is an estimate of daily exposure to humans that is likely to be without appreciable risk of adverse effects during a lifetime.