Examples of the Dose Extrapolation

Due in large part to all of the uncertainties associated with this process, the U.S. EPA, the WHO, and other regulatory bodies have developed a standardized set of uncertainty factors that are used to conduct extrapolation of toxicity values across species  

Factor of 10 to extrapolate from another species to humans (now divided into two factors of three each by some agencies when both factors are used it is rounded to 10, rather than 9, which is the product of 3 times 3) 

Factor of 10 to extrapolate from an average human to a sensitive human 

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