Putting Risk Into Perspective
Simply knowing how many pounds of any substance are used or produced by a facility provides no information about health or environmental risk. To evaluate risk requires knowing whether people are exposed to a substance at levels that would pose a concern. In the case of power plant emissions reported under EPCRA, ground-level concentrations are so low they do not pose a significant health concern.
In general, federal agencies such as EPA, the Food and Drug Administration, and others use "one in a million" as the level of risk to the general population below which they see no need to consider regulatory action.
Studies of the power plant emissions included in the EPA inventory show that possible health risks associated with releases from power plants range from one in 1 million to one in 100 million, or up to 100 times less than the level accepted by various federal agencies.