On October 5th, operators of Japan’s abandoned Fukushima Daiichi nuclear power plant Pumping of wastewater has resumed It has been held at this facility for the past 12 years. TEPCO plans to release about 7,800 tons of treated water into the Pacific Ocean over the next two and a half weeks.
This is TEPCO’s second release of nuclear power plant wastewater, following the first release in September. The plan is for this process, approved and supervised by the Japanese government, to continue intermittently for approximately 30 years. However, this approach is controversial. According to public opinion polls, approximately 40% of Japanese people I’m against itand it caused a backlash These opinions come from environmental activists, local fishermen, Korean citizens, and the Chinese government who are concerned that radioactivity will have a negative impact on the Pacific ecosystem and contaminate seafood.
Globally, some scientists say there is no need to worry. “The dosage is [or radiation] “It’s really incredibly low.” jim smith, an environmental scientist at the University of Portsmouth, UK. “Even if you’re eating locally caught seafood, the impact is lower than a dental X-ray.”
Smith guarantees water safety opinion article Published in a magazine published on October 5th science. The International Atomic Energy Agency supported TEPCO’s process and also vouched for its safety. But experts in other fields have strong concerns about the continuation of the pumps.
“There are hundreds of clear examples showing that high radioactivity levels have harmful consequences,” he says. Timothy Mousseaua biologist at the University of South Carolina.
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After a tsunami hit the Fukushima nuclear power plant in 2011, TEPCO desperately began flushing water to its six reactors to prevent them from overheating and causing further catastrophe. The resulting 1.25 million tons of radioactive wastewater was stored in tanks on site. TEPCO and the Japanese government say the water will have to be moved elsewhere if the Fukushima Daiichi nuclear power plant is decommissioned.
TEPCO says that over the past 10 years it has been able to: treat wastewater A series of chemical reactions cleanses most of the contaminant radioactive isotopes, including iodine-131, cesium-134, and cesium-137. But much of the current controversy revolves around one isotope that the treatment failed to remove: tritium.
Tritium is a hydrogen isotope with two extra neutrons. A byproduct of nuclear fission, it is a radioactive substance with a half-life of approximately 12 years. Because tritium shares many properties with hydrogen, its atoms can penetrate water molecules and create a radioactive liquid that looks and behaves much like what we drink.
This makes it difficult to separate tritium from nuclear wastewater. In fact, there is no existing technology that can treat the tritium present in the vast amounts of water contained in the Fukushima nuclear power plant.Some of the plan’s opponents Authorities insist all releases should be postponed Until scientists developed a system that could purify tritium from large amounts of water.
But TEPCO claims it is running out of space to store wastewater. As a result, they chose to heavily dilute it (1 part tritiated water to 100 parts “clean” water) and pipe it into the Pacific Ocean.
“Both Fukushima and TEPCO have no choice but to release water,” he said. Awadesh Jha, an environmental toxicologist at the University of Plymouth, UK. “This is an earthquake and tsunami prone area. They can’t store it and have to deal with it.”
Citing environmental research by him and his colleagues, Smith believes that the same properties of tritium that hide it in water molecules mean it doesn’t accumulate in marine life. They have been studying fish and insects in lakes, pools and ponds downstream of the Chernobyl disaster for decades. “We haven’t really found any significant effects of radiation on the ecosystem,” Smith said.
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Additionally, Japanese authorities are testing seawater during the initial release. No recordable levels of tritium were found.Smith believes this is due to dilution of wastewater.
But Jha cautions that the initial releases barely scratched the surface of Fukushima’s wastewater, and scientific evidence about tritium’s effects in the ocean is mixed. Many questions remain regarding tritium’s powerful effects on different biological systems and different parts of the food chain.Some results show that the isotope May damage fish chromosomes They can be as effective as high-energy X-rays or gamma rays, and can have negative health effects later in life.
Additionally, experts have discovered that Tritium can combine with organic matter They exist in a variety of ecosystems and persist there for decades. “These issues are not being adequately addressed,” Jha said.
Smith claims the emissions contain less tritium than natural sources. cosmic rays It hits the upper atmosphere and rains tritium from above. They also say that damage to fish DNA does not necessarily correlate with negative effects on wildlife or humans. “We know that even low doses of radiation can damage DNA, but that alone is not enough to damage the way organisms reproduce, survive, and develop,” he says. says.
“We don’t know if the impact of releasing water is negligible, because we don’t actually know how much radioactive material will actually be released in the future,” counters Mousseau. He added that independent monitoring of the process could allay some of the environmental and health concerns.
Smith and other supporters of the TEPCO plan point out that that’s not really the case. General method In the nuclear industry. Power plants use water to naturally cool reactors, which means large amounts of tritium-containing waste are disposed of. This is because it is nearly impossible to remove tritium from large amounts of H.2Current technology, power plants have 0 (Including within China) Re-dumping into water bodies at concentrations higher than those released in Fukushima.
“That’s not a reason to keep discharging,” Jha said. “We need to work more on what it does.”
If tritium levels remain low, as guaranteed by TEPCO and Smith, seafood from this region will likely be safe to eat. But many experts, like Mousseau and Jha, don’t think there’s enough scientific evidence to say that for sure.
