Update March 18: New interview on Japanese radiation risk with atmospheric physics researcher.
It's human nature to view catastrophes like those hitting Japan through a self-protective lens. Thus, when I woke up this morning, my first concern, irrational or not, was about any potential danger from trans-continental radiation traveling our way.
Apparently, I'm not the only one. From the Santa Rosa Press Democrat:
Fear of nuclear fallout from Japan's earthquake- and tsunami-battered nuclear power plants has created a nationwide scramble for potassium iodide, a compound that can protect thyroid glands from radioactivity. "We sold out," said Maxine Ward, who works in the supplement department of the Ukiah Natural Foods Co-Op...
Ward has ordered more potassium iodide, but national retail suppliers have been swamped with requests. "They're all out of stock," said Leila-Anne Brusseau, at Santa Rosa Community Market. The store normally does not stock the product but has been trying to get some because of demand. "I'm getting a call every five minutes," Brusseau said. She said her main supplier told her they'd sold out after filling 1,200 orders in the first half hour of business on Monday.
The quest for anti-radiation pills appears to be an overreaction, at least according to the government, scientists, and health experts. From the U.S. Nuclear Regulatory Commission on March 13: "NRC Sees No Radiation at harmful levels Reaching U.S. From Damaged Japanese Nuclear Power Plants."
From a San Jose Mercury News article this morning:
Northern Japan, where a 9.0 earthquake and tsunami crippled the cooling systems at three reactors at the Fukushima Daiichi Nuclear Power Station, is about 5,000 miles from the West Coast of the United States. The amount of material released so far -- mostly radioactive steam -- has not been in large enough quantities to pour into the upper atmosphere and blow across the Pacific Ocean, experts said Monday.
"Based on what has happened to date, there is essentially zero risk," said Jerrold Bushberg, director of health physics programs at UC Davis.
"No appreciable amount of radioactive material will reach Hawaii or the West Coast," said Bushberg, who specializes in radiological emergency preparedness. "Anything there was would be so diluted, from rains over the Pacific Ocean, it would precipitate into the ocean. It wouldn't be anything I would be concerned about..."
If a full-scale meltdown occurs in Japan, with a massive fire and explosion, and loss of containment, as happened at Chernobyl, that could send large amounts of radioactive material into the air, drifting above 5,000 feet, where weather patterns could bring it to the United States. Even then, the material would be spread out very widely.
Sarah Varney, health reporter for The California Report, talked to Professor Bushberg, quoted in the article above, and he reiterated the lack of risk to Californians from the Japanese accident:
KQED newscaster Joshua Johnson talked to Dr. Tony Van Curen, an atmospheric scientist with the California Air Resources Board, about the likelihood of radioactive emissions reaching our shores. Dr. Van Curen said the current levels of radioactive release don't have a high potential to make it across the Pacific. If another explosion occurred venting particles higher into the atmosphere, then some fallout could very well travel our way, but it would be very dilute and spread out.
He also said that even in the most serious nuclear accident to date, at Chernobyl, the long-lasting deleterious health effects were limited geographically to the immediate area.
A bevy of health experts being interviewed by the press are advising people not to take potassium iodide. "It would be dangerous and not wise to take iodine without a reason," the Press Democrat quotes Dr. Craig McMillan, Mendocino County's public health officer.
The California Report's Rachael Myrow talked to Mike Sicilia, spokesman for the California Health Department, about radiation concerns, and he too counseled Californians to skip the iodine because "there is no nuclear emergency." He did however, note that half of all state citizens don't have an updated emergency kit, which should include a three-days supply of water and personal prescription medications.
You can listen to The California Report segment, which also includes an interview about the safety of the San Onofre nuclear facility with an expert on nuclear containment leak-rate testing. He says that the station is built to withstand a 7.0 quake, a higher magnitude than the 6.4 limit projected for the area. The last interview is with a PG&E spokesman about the safety of San Luis Obispo's Diablo Canyon Nuclear Power Plant, which sits near several fault lines.
And here's a KTVU video report about the Bay Area radiation detectors deployed by the EPA's National Air and Radiation Environmental Laboratory (RadNet). One detector sits atop the roof of the Bay Area Air Quality Management District office on Ellis and Van Ness in San Francisco, and one each has been set up in San Jose and Sacramento. The report says that the detectors are sensitive enough that they picked up particle traces from North Korean nuclear tests.