Photo/IllutrationInspectors take a sample of groundwater to check for toxins at the Toyosu market site in Tokyo’s Koto Ward in February. (Asahi Shimbun file photo)

An expert panel insists a new Tokyo fish market is safe despite its high levels of toxins below ground, but the fate of the long-planned facility will come down to the conclusion of one politician.

The decision rests with Tokyo Governor Yuriko Koike, whose government called for the latest study that confirmed levels of benzene, arsenic and cyanide above safety standards in groundwater at the market site in Toyosu, Koto Ward.

“I am taking (the findings) very seriously,” Koike said after the results were released at a meeting on March 19 by the panel of experts set up at the Tokyo metropolitan government. “I will consult with the panel and other parties over information on which I will weigh what to do.”

The Toyosu market has been completed as a replacement for the world-famous but aging Tsukiji fish market in Chuo Ward. The relocation plan is now up in the air.

Speaking of the latest findings, Tatemasa Hirata, director of the Wakayama Study Center of the Open University of Japan who heads the panel looking into safety issues at the Toyosu site, repeated that the new market is safe.

“When making the assessment, we separate the area above ground from the area below ground,” he said. “As far as figures at monitoring spots above ground are concerned, they remain the same and can be called safe scientifically.”

The panel also said the groundwater at the Toyosu site will not be used for drinking or cleaning. In addition, the experts point out that a layer of concrete separates the portion dealing in food at the market from the basement levels.

But Hirata acknowledged that politicians will make the ultimate decision.

“When it comes to whether consumers feel assured and comfortable (with the relocation), it will be a political issue, which we cannot call,” he said.

Some traders who attended the panel’s meeting expressed anxiety over the Toyosu market despite the panel’s safety assurances.

“Now, doubts about the land in Toyosu have grown too large to wipe out,” one of them said.

The Tsukiji market was scheduled to be relocated to Toyosu in November last year, but Koike delayed the move.

After she took office in August, it was found that the initial plan to use fresh soil to elevate land under the main buildings at the market to mitigate contamination had been ignored. In addition, two surveys found contamination at many monitoring spots at the Toyosu site, which was once occupied by a Tokyo Gas Co. factory.

The results of all seven preceding surveys since 2014 showed toxin levels were within national environmental standards.

But the eighth study, conducted in August and September last year, found three of the 201 locations exceeding the safety limit. And the ninth study, conducted in November and December 2016, showed toxin levels vastly different from those recorded in previous studies.

In the latest study, benzene was found at its highest concentration--1 milligram per liter, or 100 times the safety limit of 0.01 milligram per liter.

In addition, a maximum 0.036 milligram of arsenic per liter was discovered, exceeding the safety standard of 0.01 milligram per liter.

Safety standards also dictate that cyanide must not exist in the environment because of its extreme toxicity. But a level of 1.4 milligrams of cyanide per liter was detected at the site.

Overall, the 10th study found toxin levels exceeded safety standards at 25 of the 27 locations monitored. Those 27 areas showed high levels of toxins in the ninth survey, which discovered toxic substances at 72 of 201 monitoring spots.

A concentration of benzene 79 times the safety threshold was also detected in the ninth study.

The Tokyo metropolitan assembly is conducting a special investigation on why the metropolitan government picked the Toyosu site.