Dose response

Dose response is the change in effect on an organism caused by differing levels of exposure to a substance. This may apply to individuals (eg: a small amount has no observable effect, a large amount is fatal), or to populations (eg: how many people are affected at different levels of exposure).

Studying dose response, and developing dose response models, is central to determining "safe" and "hazardous" levels and dosages for drugs, potential pollutants, and other substances that humans are exposed to. These conclusions are often the basis for public policy.