Which statement about the hazard quotient HQ is true?

Which statement about the hazard quotient HQ is true?

• A. HQ is calculated as CDI minus RfD; HQ > 1 indicates potential for non-cancer adverse effects
• B. HQ is calculated as CDI divided by RfD; HQ > 1 indicates no risk
• C. HQ is calculated as RfD divided by CDI; HQ > 1 indicates higher cancer risk
• D. HQ is calculated as CDI divided by RfD; HQ > 1 indicates potential for non-cancer adverse effects

Answer: (D)

Hazard quotient (HQ) is about comparing how much of a contaminant people are exposed to with a safe reference level. The HQ is calculated as the chronic daily intake (CDI) divided by the reference dose (RfD). If this ratio exceeds 1, there is potential for non-cancer adverse effects; if it’s below 1, the exposure is typically considered unlikely to cause those effects. This approach specifically addresses non-cancer endpoints, while cancer risk is assessed using different methods. The other statements misstate either the calculation or the interpretation: subtracting CDI and RfD is not how HQ is determined, reversing the ratio would invert the meaning, and linking HQ > 1 to cancer risk or to no risk is not correct.

Hazard quotient (HQ) is about comparing how much of a contaminant people are exposed to with a safe reference level. The HQ is calculated as the chronic daily intake (CDI) divided by the reference dose (RfD). If this ratio exceeds 1, there is potential for non-cancer adverse effects; if it’s below 1, the exposure is typically considered unlikely to cause those effects. This approach specifically addresses non-cancer endpoints, while cancer risk is assessed using different methods. The other statements misstate either the calculation or the interpretation: subtracting CDI and RfD is not how HQ is determined, reversing the ratio would invert the meaning, and linking HQ > 1 to cancer risk or to no risk is not correct.