Definitions for "Hazard Quotient"
Ratio of toxicant exposure (estimated or measured) to a reference value regarded as corresponding to a threshold of toxicity: if the total hazard quotient from all toxicants to a target exceeds unity, the combination of toxicants may produce (will produce under assumptions of additivity) an adverse effect. RT hazard, pollutant, toxic substance.
The ratio of a single substance exposure level over a specified time period (e.g., sub-chronic) to a reference dose for that substance derived from a similar exposure period.
is used to measure potential human health hazards from noncarcinogenic substances. The HQ is the ratio of the daily intake of a specified noncarcinogenic substance during a specified time period over (divided by) a reference dose for a similar time period. If the HQ exceeds one, the possibility exists for systemic toxic effects. HQ = Daily intake/Reference dose.