Low levels found in air and rainwater in U.S.
As a result of the incident at the Fukushima nuclear plant in Japan, several U.S. Environmental Protection Agency (EPA) air monitors have detected very low levels of radioactive material in the United States consistent with estimates from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public health concern.
Elevated levels of radioactive material in rainwater have been expected as a result of the nuclear incident after the events in Japan since radiation is known to travel in the atmosphere. Precipitation samples collected by EPA in the states of California, Idaho and Minnesota have seen very slightly elevated levels of radiation.
In addition to iodine-131, EPA monitors also have identified trace amounts of other isotopes, which EPA expected to see because they are consistent with releases from the damaged Japanese nuclear reactors.