No detectable amount of tritium has been found in fish samples taken from waters near the crippled Fukushima Daiichi nuclear plant, where the discharge of treated radioactive water into the sea began a month ago, the Japanese government said Monday.

Tritium was not detected in the latest sample of two olive flounders caught Sunday, the Fisheries Agency said on its website. The agency has provided almost daily updates since the start of the water release, in a bid to dispel harmful rumors both domestically and internationally about its environmental impact.

Fish are unloaded at a port in Soma in Fukushima Prefecture, northeastern Japan, on Sept. 1, 2023, as bottom trawling starts off the prefecture after a two-month closure and for the first time since the release of treated radioactive water from the crippled Fukushima Daiichi nuclear power plant. (Kyodo) ==Kyodo

The results of the first collected samples were published on Aug. 9, before the discharge of treated water from the complex commenced on Aug. 24. The water had been used to cool melted nuclear fuel at the plant but has undergone a treatment process that removes most radionuclides except tritium.

The remaining tritium is then diluted to one-40th of the concentration permitted under Japanese safety standards before being released into the Pacific Ocean via an underwater tunnel 1 kilometer from the seaside plant, which was wrecked by a massive earthquake and tsunami in 2011.

Samples of local fish have been collected at two points within a 5-km radius of the discharge outlet, except during rough weather conditions, with the agency announcing its analysis results on an almost daily basis since Aug. 26.

No tritium was detected in 64 fish, which included flounder and six other species, collected since Aug. 8.

The results are currently available in both Japanese and English, but it remains to be decided whether the agency will change the frequency of its updates or provide them in other languages, such as Chinese.

The agency plans to examine approximately 180 samples by the end of March 2024, with the collection points expected to remain unchanged.

"Due to growing momentum for supporting Fukushima following China's ban on Japanese seafood imports, there appears to have been no significant reputational damage domestically," an agency official said.


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