After detecting higher-than-normal levels of radiation in their measurements, Florida power companies are attributing the increases to a damaged nuclear plant in Japan.
The radiation levels don't create an immediate health threat and are well below the normal radiation exposure people experience every day, representatives from the companies and government agencies said Monday.
Progress Energy detected very low levels of iodine 131, a by-product of the nuclear fission process, in the air at its nuclear plant in Crystal River. Florida Power & Light had similar findings at nuclear plants in Fort Pierce and Miami-Dade County.
However, readings at the Environmental Protection Agency's five Florida monitoring stations — Tampa, Jacksonville, Tallahassee, Orlando and Miami — have remained normal.
Florida is about 7,000 miles from the Japanese plant.
Nuclear Regulatory Commission inspectors are based at Crystal River, but an agency spokesman said they took no action.
"We don't see any reason at this point to have any concern about the levels that have been reported," said Roger Hannah of the NRC.
The Crystal River plant has been offline since September 2009 when it was shut for refueling and maintenance. Its reopening was delayed by the discovery of cracks in the reactor building.
Japan's Fukushima Dai-ichi nuclear plant has been making headlines ever since the March 11 earthquake and resulting tsunami damaged the facility, causing radiation to leak.
There is no way to know for sure if the additional radioactive material was produced at the Japanese plant. But increased levels of radioactive material have been detected at several sites in the United States, and all attributed to the crisis in Japan.
Radiation was found in samples of rainwater from Boston and at power plants in Pennsylvania. Progress Energy found increased levels of iodine 131 at a second plant in South Carolina.
The EPA's monitoring systems detected increased radiation in California, Alaska, Alabama, Hawaii, Idaho and Nevada.
The elevated radiation levels are expected to be only a short-term issue, according to the EPA.
"None of the levels we're seeing are of public health concern at this time," said Davina Marraccini, a spokeswoman.
The nation's nuclear power companies continuously monitor radiation levels at each plant, studying the air, soil, drinking water, precipitation and milk. When power plants detect radiation at certain levels, they are required to file reports with state and federal agencies. That threshold is well below the level considered harmful to humans.
Though the radiation levels detected at the Crystal River plant did not meet thresholds requiring formal action, Progress Energy voluntarily reported its findings on Friday to the Florida Department of Health's Bureau of Radiation Control.
Because the power companies have sensitive equipment that detects extremely low levels of radiation, they can track the effects of the Japanese incident, said Ralph Andersen, chief health physicist for the Nuclear Energy Institute, which represents nuclear power companies.
But those levels are tens of thousands of times less than the natural radioactivity people are exposed to from the air they breathe, water they drink and even the sun and stars in the sky.
"These are fantastically small levels of radiation," he said.
Tia Mitchell can be reached at firstname.lastname@example.org or (813) 226-3405.