Newswise — Last year, the world experienced its second level seven nuclear power plant accident, a quarter century after the Chernobyl disaster on April 26, 1986. While both accidents reached the highest level of disaster, the amount of radioactive material released differs greatly between the Fukushima Daiichi disaster and the one in Ukraine.
Scientists agree that the dismantling and cleanup of the Fukushima plant will take decades. A Texas Tech University radiation expert who was the first American scientist allowed inside Chernobyl’s exclusion zone can discuss the differences in the two disasters, and the good news/bad news of both scenarios.
Expert
Ron Chesser, director of Texas Tech’s Center for Radiation Studies, (806) 742-3722 ext. 245, (806) 742-1737, or [email protected].Talking Points
• Though Fukushima and Chernobyl reached the same level of seriousness, that doesn’t mean that the releases of radiation were the same. Both disasters did release significant amounts of radiation. After that, they’re not very similar in the types of release and what happened. • The amount of radiation released from Chernobyl is considerably more than at Fukushima.• Reactor fuel wasn’t left open to elements at Fukushima except for old fuel rods in spent fuel pool. The reactors themselves at Fukushima didn’t breach. • At Chernobyl, an explosion breached the containment vessel and exposed nuclear fuel to the atmosphere. This blew nuclear fuel into small particles, which was lifted into the air, carried long distances by wind and dropped by gravity or rain.• About 13,230 pounds of radioactive material containing about 120 different isotopes launched into the air from Chernobyl, which burned for 10 days.• 98 to 99 percent of the radiation released is now decayed at Chernobyl. However, the 1 or 2 percent left has long decay rates and will be there for decades yet to come. However, the remaining radiation will not convey the severe dose rates seen in the first few months after the accident.• Fukushima’s fuel reactors didn’t explode because there was only a partial meltdown in three reactors. It wasn’t the typical meltdown that burned through the reactor vessel and contaminated lower parts of reactor, such as what happened at Chernobyl. • Fukushima had to release gas pressure, and those releases expelled isotopes of cesium, iodine and xenon. The Chernobyl disaster released massive amounts of those isotopes as well as about 115 other radioactive isotopes.Quotes
• “If the built-up gas pressure at Fukushima hadn’t been released, the pressure could have ruptured the reactor vessel. The workers there knew it was one of those ‘damned if you don’t, but not as damned if you do’ scenarios. They had to make several releases like that to relieve the pressure and keep the reactor vessel intact. That was their main job. They did a miraculous job. The vessels themselves proved very resilient despite a horrible accident that progressed far beyond the design of these reactors.” • “The bad news about Fukushima is that it affected more urban areas than did Chernobyl, because it’s more densely populated near the reactor in Japan. The iodine-131 is one of the volatile elements at both Chernobyl and Fukushima. It has lots of good news and bad news.” • “The good news with iodine-131 is that it has an eight-day half-life. After 40 days, most of it has decayed. The bad news is it’s given all its energy during that time period. This can cause a rapid dose to the thyroid gland. In adults, it’s not as dangerous. In adolescents with very active thyroid, it can cause cancers that don’t show up right away. Near Chernobyl, thyroid cancer rates didn’t show a significant increase until about eight years after the accident. Iodine shouldn’t be a major problem now.”• “With cesium-137, the bad news is its long half-life of 30 years. But the good news is it doesn’t convey a quick dose of radiation.”• “Worldwide, we’ve propagated this radiation phobia. Scientifically when you look at radiation at normal levels of exposure, it is a very poor carcinogen. There are many other chemicals out there that are far more carcinogenic. One thing we need to do in the future is integrate into public education the scientific realities of radiation so that when we have events, we can have a rational response. I’m not saying people shouldn’t be concerned or scared. But many responses were way out of proportion with reality. People cleared out iodine tablets in Lubbock. We couldn’t even detect radiation levels from Japan here. That kind of panic is due to fears when we’re afraid of what we don’t understand.”
RSS