Tiny amounts of radiation detected in Hawaii milk and rainwater don’t pose a public health threat, state health officials told senators today.

Radiation traveled through the air to Hawaii following explosions at three nuclear reactors in Japan last month, but it falls far short of dangerous dosage levels, even after extended exposure, members of the Department of Health said.

"The levels we’re seeing are very low. There’s no public health risk to the drinking water and to the milk," said Lynn Nakasone, administrator for the department’s Environmental Health Services Division.

The department reported last week it found 18 picocuries per liter of iodine-131 in Big Island milk, significantly below the 4,700 picocuries per liter at which the U.S. Food and Drug Administration would take steps to safeguard the public, such as removing milk from store shelves. Rainwater tested in Hawaii had two picocuries per liter.

Radiation carried through the air and clouds will likely decline as time passes, said Jeff Eckerd, the state Department of Health’s acting program manager for indoor and radiological health.

"What we’re seeing now is the levels in the air are dropping, so we should see levels in water and other areas decrease over time," he said. "We’re keeping an eye on Japan because we had suspected we would see trace amounts coming here anyway from the initial three explosions."

They spoke during a public hearing held by the Senate Health Committee to inform the public about potential danger from radiation.

"We don’t have any immediate health threats," said Sen. Josh Green, D-Milolii-Waimea, the committee’s chairman.

Federal officials are keeping food products from affected areas of Japan out of the United States, said John Verbeten, director for import operations and policy for the FDA.

"For the majority of these products, for them to be introduced into U.S. commerce, they would have to be shown to be free from radioactivity contamination," Verbeten told senators during the hearing by phone. "We have not seen any analytical results of any concern whatsoever."

Drinking water in Hawaii showed no radioactivity, Nakasone said.

The health department was testing water catchment systems on the Big Island, Maui and Kauai for radioactivity this week, she said. It typically takes about a week to receive test results.

The FDA and state Department of Health said they would continue monitoring radiation and its potential effects for the foreseeable future.