This approach is a way of prioritizing and assisting with the communication of the risks associated with unavoidable exposure to genotoxic chemical carcinogens. It has been developed and used by the European Food Safety Authority (EFSA), the World Health Organization (WHO), and the International Life Sciences Institute (ILSI). It is also seeing increasing use for chemicals where no threshold can be identified, including carcinogens, for example, arsenic, but also where other health effects are observed, as in the case of, for example, lead. The MOE is the numerical value obtained by dividing a Point of Departure (POD) on the dose-response curve by estimated human exposure to the chemical. The preferred POD is generally accepted to be the lower 95% confidence limit of the benchmark dose (BMDL), although others have been suggested.

MOE=BMDL10/Dietary intake