[A new toxicological concept-acute reference dose]

Acute reference dose (ARfD) is a new concept in toxicology and risk assessment, and mainly used for assessing health effect from short-time exposure to environmental chemicals. The ARfD of a chemical was defined as "an estimate of a substance in food or drinking water, expressed on a body weight basis, that can be ingested over a short period of time, usually during one meal or one day, without appreciable health risk to the consumer on the basis of all the known facts at the time of the evaluation. It is usually expressed in milligrams per kilogram of body weight." ARfD is different from ADI and reference dose. In this review the principles and methods in establishing ARfD were explained.