ABSTRACT
Risk assessment is both old and new. Old in the sense that humans and animals survive by evaluating the risk of harm verses the benefits of action. For early humans, the hunt for food or eating a new plant involved risk of harm, but doing nothing risked starvation. In our current society, this kind of informal risk assessment is now more directed towards the risks of eating undercooked hamburger or riding a bicycle without a helmet. More formally, risk assessment now refers to a mathematical calculation of risk based on toxicity and exposure.
