Traces of radioactive Iodine-131 were found in milk in California and Washington, according to federal and state authorities who are monitoring for contamination as the nuclear crisis unfolds in Japan. But the officials say the levels are still 5,000 times below levels of concern and do not represent a public health threat.
The Environmental Protection Agency and the Food and Drug Administration said Wednesday that radiation was found in a March 25 milk sample from Spokane, Wash. The California Department of Public Health said on its website that a similar result was found March 28 in San Luis Obispo County.
The EPA always monitors radiation levels in the air at several sites throughout the country, but the agency said this week that it is increasing the level of nationwide monitoring of milk, precipitation and drinking water in response to the situation in Japan. Those substances are normally monitored for radiation only a few times a year.
EPA spokesman Brendan Gilfillan said the radiation detected in Spokane is different than what is normally found there.
"While there can be naturally occurring levels of radiation in milk -- as there are in the air, at levels far below levels of concern -- we don't generally see this particular isotope as part of those background levels," Gilfillan said.
The EPA has found very low levels of radiation in the air connected to the Japanese incident in Alaska, Alabama, California, Hawaii, Idaho, Nevada, Saipan, Guam, Northern Mariana Islands and Washington state. Gilfillan said the low level of radiation most likely ended up in the milk after a cow ate grass or drank rainwater that contained it.
The FDA, which oversees the safety of the nation's food supply, said such findings were to be expected in the coming days because of problems with the nuclear plant in Japan, and that the levels were expected to drop relatively quickly. Japan's Fukushima Dai-ichi nuclear power complex began leaking radiation after it was damaged by a devastating earthquake and tsunami earlier this month.
"Radiation is all around us in our daily lives, and these findings are a minuscule amount compared to what people experience every day," said Patricia Hansen, senior scientist at the FDA. "A person would be exposed to low levels of radiation on a round-trip cross-country flight, watching television, and even from construction materials."
The United States had already halted imports of dairy products and produce from the affected area of Japan. Other foods imported from Japan, including seafood, are still being sold to the public but are screened first for radiation.
Japanese foods make up less than 4 percent of all U.S. imports. The FDA has said it expected no risk to the U.S. food supply from radiation.