Update: Minor amounts of radiation are projected to reach SoCal by Friday, after the jump.

Could radiation from Japan's quake-stricken nuclear power plants reach Los Angeles?

It's a long shot. But a look at Pacific jet stream animation shows that what happens in Japan doesn't stay in Japan. The stream carries weather from Asia straight into the Pacific Northwest and, at times, into Southern California.

However …

… the United States' nuclear regulatory officials say not to worry: We're not going to see [added:] harmful radiation from the Japan.

Here's what the U.S. Nuclear Regulatory Commission says (PDF):

All the available information indicates weather conditions have taken the small releases from the Fukushima reactors out to sea away from the population. Given the thousands of miles between the two countries, Hawaii, Alaska, the U.S. Territories and the U.S. West Coast are not expected to experience any harmful levels of radioactivity.

Fukushima.

Fukushima.

Still, the crisis appears to be getting worse as a second housing-structure explosion at the Fukushima Daiichi Nuclear Power Station was reported Monday. Now reports indicate officials in Japan are having trouble getting seawater to the plant to cool its core.

The plant's regular cooling pumps are a FAIL because electricity was knocked out by the quake, and such energy is required to run the water pumps.

If the core isn't cooled, a meltdown could result. That's bad news, because that would mean a serious release of cancer-causing radiation.

Still, many experts are warning against West Coast citizens becoming too alarmed. Even in a worst-case scenario the effects would be quite local to Japan.

Update: U.S. Rep. Henry Waxman, ranking member of the congressional Committee on Energy and Commerce, called Monday for hearings on the earthquake safety of American nuclear power plants.

A letter from Waxman and Rep. Fred Upton, chair of the committee, notes that the Vermont Yankee plant (there are others as well) shares the same core designs as some of the ailing Japanese reactors.

Update No. 2: William H. McBride of UCLA's Department of Radiation Oncology says it's possible for us to catch some radiation from Japan, but not likely.

Even in a worst-case scenario — a meltdown at Fukushima — it would be a long shot for us to catch any significant radiation, even if the jet stream happens to be heading this way at the time.

“There is the possibility that we might be able to pick up some radiation in the atmosphere,” McBride says. “Is it a significant chance for radiation? Certainly not.”

Update No. 3: Award-winning environmental reporter Michael Collins, an LA Weekly contributor, tells us he's setting up a radiation monitoring station in Santa Monica tomorrow. Feedback from a Geiger counter will be viewable on his website in real time via web cam.

About two times the “background” radiation base (what comes from the ground and atmosphere normally) or more will be cause for concern, he says.

The station should be able to tell us how much radiation has come over from Japan.

He hopes the station will become a cornerstone of a national network of private radiation monitors who will take advantage of the web. Already, he says, several environmentalists have vowed to tie in with their own Geiger counters.

Check in with his site here.

Update No. 4: Things went from bad to worse Tuesday morning (Japan time) when a third blast was reported at Fukushima. The exteriors of all three reactors have now seen blasts as a result of Friday's quake. It appears radiation-infected steam build up caused the explosions but the exact cause of Tuesday's blow up was as yet unclear.

Update No. 5: The situation at Fukushima got even worse Tuesday as Japanese Prime Minister Naoto Kan told his nation there was a “very high risk” of radiation in the area following the third blast.

CNN reported that radiation levels near Fukushima were four times previous levels.

The blasted reactor wasn't the only issue, either. Turns out Fukushima has a fourth reactor that was taken off-line before the earthquake for refurbishing. But as any scientist familiar with fusion basics will tell you, that doesn't mean that there's an on-off switch there, and a lack of cooling for spent rods there seems to have caused a fire that can be just as dangerous as the blasts, according to the New York Times.

People within about 18 miles (30 kilometers) were told to stay indoors.

The good news for residents was that the weather was pushing contaminants offshore, over the Pacific. Does that mean they're headed our way? We'll be watching

Update No. 6 (Wednesday): Mayor Villaraigosa issued a statement late Tuesday telling his subjects not to worry:

Despite the growing nuclear crisis in Japan, health and emergency management officials from the City and County of Los Angeles, neighboring jurisdictions, and the State of California have determined that there is no immediate threat to the United States.

We will continue to monitor any changes and stay in close contact with our public health partners as this situation unfolds. Should the situation change, we will share any relevant information.

We continue to extend our thoughts and prayers to the people of Japan, and stand ready to help in their recovery from this tragic earthquake.

Update No. 7: U.S. Ambassador to Japan John V. Roos stated Wednesday that Americans near the reactors should move. The Weekly was sent this statement:

… We are recommending, as a precaution, that American citizens who live within 50 miles (80 kilometers) of the Fukushima Nuclear Power Plant evacuate the area or to take shelter indoors if safe evacuation is not practical.

Update No. 8: KTLA News reported last night that there was a run on potassium iodide in the L.A. area despite experts' opinions that harmful radiation would not reach the region.

L.A. County Public Health chief Jonathan Fielding warned against taking the pills, which can prevent thyroid cancer in the event of radiation exposure (he said if a true need for them arose that he'd be the first person to let us know):

Residents who ingest potassium iodide out of concern of possible exposure from this situation are doing something which is not only ineffective, but could also cause side effects.

Meanwhile the U.S. Environmental Protection Agency said it was expanding radiation monitoring the western U.S. as part of its “continuing effort to make our activities and science transparent and available to the public.”

Radiation will head to SoCal.; Credit: New York Times

Radiation will head to SoCal.; Credit: New York Times

Update No. 9: Scientists at the United Nations in Austria say the jet stream will have carried some of the Fukushima radiation to Southern California by Friday. (See a map of the jet stream's movement here).

But they warned that the amounts would be insignificant and not enough to cause alarm about health risks.

The stream will also reach Nevada, Utah and Arizona, according to the New York Times.

First posted at 1:05 p.m. Monday

Advertising disclosure: We may receive compensation for some of the links in our stories. Thank you for supporting LA Weekly and our advertisers.