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hazard quotientAbbreviation: HQ
A numerical ratio used to estimate whether a toxic exposure will prove harmful to an exposed person or ecosystem. The ratio is typically expressed as the measurable toxic exposure to a screening benchmark, such as the highest concentration of the toxicant known not to cause harm. An HQ greater than 1.0 is potentially toxic. An HQ less than 1.0 is not toxic, unless the toxic exposure is to multiple substances each with its own biological or ecological risk.
See also: quotient