With the continued flow of radioactive water into the sea from the crippled Fukushima No. 1 plant, consumers at home and abroad are concerned about the safety of seafood around Japan.

To ease such concerns and demonstrate how fisheries products are being monitored, the Fisheries Agency held a media tour last week to a research facility in Onjuku, Chiba Prefecture, that attracted 36 participants, most of them foreign journalists and embassy officials.

The tour demonstrated the monitoring process, which participants said was well-organized and helped them better understand the efforts, although they said the agency’s explanations fell short in helping them grasp the whole picture.

Some of the visitors also said the government should have conducted this kind of tour much earlier.

Atsushi Suginaka, a director in the Fisheries Agency’s processing industry and marketing division, claimed many people erroneously believe the radioactive water reaching the Pacific poses health risks to people who eat fish, noting that this “concern” has spread widely.

“We have repeatedly (denied this), but few media outlets have seen the actual monitoring process, so we thought it would help them understand the situation better if they see how the process works,” Suginaka said.

The tour took place at Marine Ecology Research Institute in Chiba Prefecture, where the Fisheries Agency directly outsources the monitoring of various fish species.

The facility typically receives around 50 fish a day that were caught off eastern and northeastern Japan.

The species subject to the tests include those whose radiation levels exceeded 50 becquerels per 1 kg in tests conducted in the last fiscal year. The legal limit for fish is 100 becquerels per 1 kg.

The tests target not only fish that remain in one area but also those that travel long distances, seasonal varieties that are popular with consumers and especially bottom fish, because radioactive materials tend to settle on the ocean floor.

The species delivered to the research center during the media tour included “tara” (Pacific cod), “hirame” ( flounder), (surume-ika) Japanese flying squid and “sake” (salmon).

The tour covered the arrival of the samples in the morning and their later dissection for radiation screening.

Each fish is cut the way a chef would do it to ensure that the parts people are most likely to eat are tested.

The minced samples are monitored by germanium semiconductor detectors, and it takes about an hour to get the results.

The detectors, which cost about ¥20 million, can gauge the levels of radioactive iodine and cesium.

During the four-hour tour, journalists from overseas eagerly observed each process and asked questions, including how the species were selected, how often the test is conducted and if it is OK not to test for other radioactive substances, particularly strontium.

Tests for strontium contamination are carried out at another facility, but those results take about a month, so the samples are limited, the Fisheries Agency said.

Current regulations meanwhile assume a general radioactivity threshold that would apply to substances not covered by the checks that is based on the level found in the substances screened.

For example, if a sample’s cesium level is within safe consumption limits, it can be assumed that any isotopes not checked for, including strontium, would also be within those limits, the agency said.

While there were not many samples, the tests conducted from September 2012 to last June show that the highest level of strontium detected was 6 becquerels per kilogram, which the government says is unlikely to pose a significant health risk to humans.

The officials from the Fisheries Agency stressed that the monitoring results show that the impact of the nuclear crisis on fish is now subtle even in the sea near Fukushima.

Results from the cesium density test in the first three month after the meltdown catastrophe started in March 2011 showed that 53 percent of fish caught around Fukushima exceeded the legal limit of 100 becquerels per kilogram, but now only 2.2 percent of fish caught top this threshold. Regardless, fish caught within 20 km of Fukushima No. 1 are not shipped to market.

As for fish caught far from Fukushima, more than 14,000 samples have been tested in the past year and only 88 exceeded the legal cesium safety limit of 100 becquerels per kilogram.

The cesium monitoring tests have been conducted weekly in principle.

If samples exceed the safety limit, species caught in the same area won’t be shipped to markets.

Participants said the tour helped them better realize how fishery products are being monitored.

“It was my interest in understanding more how they are dealing with the contamination and how they were reassuring the public about the safety of the food,” said one of the foreign participants, declining to be named.

“I found the tour very valuable. I think the Japanese authorities should do more of these to promote awareness of the testing undertaking.”

But some said the government should have organized such an event much sooner.

“I was surprised to know that this is the first tour. It’s been almost three years from the nuclear accident,” said Andres Sanchez Braun, a journalist at Agencia EFE, a Spanish government-owned news agency.

He also said that although the monitoring test at the facility seemed solid, the Fisheries Agency’s explanation about the government’s overall monitoring effort is unclear.

For example, he said, each prefecture has its own survey program, but the tour didn’t clarify if the individual checks are based on unified survey methods and standards.

Currently, the central government asks the prefectures of Hokkaido, Aomori, Iwate, Miyagi, Fukushima, Ibaraki and Chiba, to conduct tests on fish caught in the Pacific. Each prefecture draws up a monitoring regimen based on guidelines.

On top of that, 10 prefectures in eastern and northeastern Japan are asked to check the radiation levels on fish in rivers and lakes.

The Fisheries Agency said other prefectures are also doing voluntarily tests and reporting the results to the central government.

Vivek Pinto, a freelance journalist from India, said the tour itself showed that the monitoring process contributes to ensuring food safety based on scientific data.

But there are still people who are afraid to eat fish, so the government needs to address those concerns.