Radiation Levels Still Safe in Japan

Published March 18, 2011

A week after the magnitude 9.0 earthquake and subsequent tsunami killed thousands of people in northern Japan, Japanese officials reported not a single civilian had been exposed to levels of radiation that would threaten human health.

Widespread Testing, Reassuring Results
Thousands of people were evacuated from within a 15-mile radius of the Fukushima nuclear power reactors. Japanese officials have tested more than 1500 evacuees for elevated radiation. Technicians thoroughly tested the clothes and shoes of evacuees with radiation detectors at several checkpoints and shelters. The vast majority tested out at normal radiation levels, while roughly a dozen showed modestly elevated radiation still within safe levels.

Those with modestly elevated radiation levels were advised to change their clothing and wash their hands as a safety-first measure.

“There is no fear of contamination among local residents,” a Japanese government spokesman told the press, as reported in the March 18 Christian Science Monitor. “No one has been found with levels that pose a threat to health.”

Spectacular Challenges Encountered
The six nuclear reactors at Fukushima, which were designed to withstand a magnitude 8.2 earthquake, remained in damaged but stable condition. The historically strong earthquake and tsunami presented several challenges. The facilities were shaken to their foundations, and containment buildings were damaged. At least three chemical explosions occurred and spread resulting fires. A loss of power prevented pumps from delivering water to cool the nuclear fuel rods.

These factors combined to cause a partial melting of some of the nuclear fuel rods.

Meltdown Nothing Like a Bomb
Even under such spectacularly challenging conditions, however, the nuclear reactors are performing admirably, said Jay Lehr, science director for the Heartland Institute and coauthor of the Wiley Encyclopedia of Nuclear Energy.

“It is likely that at least one of the Fukishima reactors will totally melt down, but the danger to human health will remain slight,” Lehr said. “Sadly because the nuclear industry has made no effort to educate the public about nuclear power, the media and public equate a plant meltdown to a nuclear bomb,” Lehr explained.

“These two phenomena bear no resemblance, of course. When heat gets out of control the plant is shut down, but it takes days to remove the residual heat and radiation. If cooling pumps fail, the heat may ultimately melt the fuel rods. If vapor escapes the reactor when gas is vented to reduce pressure, a small buildup of radiation will be experienced for some miles away from the reactor, but radioactive gases and chemicals will quickly disperse. Area citizens may be exposed to low levels of radiation, but this will not cause long-term health problems.”

Safety Record Overlooked
“These reactors are designed to withstand virtually all disaster scenarios and to continue to contain the radioactive materials safely inside of them,” said nuclear physicist Rusty Towell, a physics professor at Abilene Christian University who has taught at the U.S. Naval Nuclear Power School. “This is precisely what happened at Three Mile Island. There was a core meltdown, yet virtually no radiation was released outside of the site. There were no casualties and no harmful health effects to others. Currently, the Japanese reactors are also performing this well.”

Even after the worst nuclear incident in history, the complete failure of the Chernobyl nuclear power plant in the Soviet Union, fewer than 50 people died as a result of nuclear radiation. Most of these deaths, according to a 2005 United Nations report, were among rescue workers, not civilians.

Promising Outlook
“Nuclear physicists in Japan have been monitoring their local radiation levels. One group of physicists at a research lab about 120 miles from the reactors has been monitoring this since the accident began and has seen only one reading above background levels, and it was small and lasted only a brief time,” Towell explained.

“Many of the designed safety systems are still functioning. As long as the core is contained by the steel and concrete containment vessel—think of a bomb shelter on steroids—then the released radiation will continue to be minimal and no real negative health effects will be seen outside of the immediate area. Currently, there are no reasons to believe anything else will occur,” said Towell.

He added, “As Japan works to rebuild after this horrible natural disaster, there are lots of real dangers that many people will be faced with, including the potential for additional aftershocks, damaged buildings collapsing, the spread of disease due to the lack of clean water, and the risk of exposure for those outside in the snow. There is no reason now to believe that any normal Japanese citizens will suffer from radiation exposure.”

James M. Taylor ([email protected]) is managing editor of Environment & Climate News.