Hazard Quotient (HQ)

The Hazard Quotient (HQ) is a risk factor applied to non-carcinogens. It relates the dose delivered at the exposure point (the Average Daily Dose, ADD) to a toxicological end-point. This comparison helps determine if exposure to a chemical poses a significant risk. The HQ is calculated by dividing the estimated exposure level by a reference dose (RfD), which represents the maximum acceptable oral dose of a toxic substance.