As our team in Japan continues to monitor the radioactive contamination of land and sea that resulted from the destruction of the Fukushima Daiichi reactors, we’re still finding very disturbing evidence.

The results of another round of analysis of seafood caught in Japanese waters are in (you can read about the last round of results here), and show us once again that the Japanese government and retailers are still not doing enough to protect people from the contamination.

Between October 12 and November 8 our team, led by Greenpeace Japan Oceans Campaigner Wakao Hanaoka, took seafood samples from the same five supermarket chains - Aeon, Ito Yokado, Uny (Apita), Daiei and Seiyu - [DW1] as featured in the first round of research, taking 15 samples from each. Of the 75 samples, radioactive cesium 134 and 137 were detected in 27. There was no company whose products were not contaminated.

The samples that stood out were from Pacific cod. In total, seven cod caught in Hokkaido, Iwate and Miyagi, were sampled and five were found to be contaminated. A sample from a cod caught in Hokkaido and sold at the Uny Totsuka Shop in Kanagawa prefecture, showed a contamination of 47.3 Becquerel per kg. Japanese researchers have just announced they believe 80% of the radiation from Fukushima fell into the Pacific ocean. Like elsewhere in the world, cod is a very popular fish among Japanese people.

The Pacific cod wasn’t the only contaminated fish we found. Cesium 134 and 137 were detected in all five samples of Bigeye tuna we took and in all five samples of Skipjack tuna.

Wakao and the team also analysed one sample of canned mackerel. Although the level of contamination was not very high (4.6 Becquerel per kg), there is no detailed information about the fish’s origin such as where it was caught and what type of mackerel it is. The label on the can simply says “made in Japan”. The government's labelling regulation for canned fish and processed fish products is far less stringent than for fresh fish products and needs to be addressed immediately.

This evidence shows contamination below the Japanese limits government’s official limit of 500 Becquerel per kg but it still poses a health risk, particularly for children and pregnant women. It’s clear that radioactive contamination has entered Japan’s food chain and is being spread by the country’s food distribution system.

We’re now eight months into the Fukushima crisis and yet, with many examples of radioactive contamination in food being found, the government is still showing no sign of establishing an official, national food screening and labelling system that would give shoppers much needed information and help protect their health. How long do the Japanese people have to wait?

To reduce this spread of contamination Greenpeace is continuing to pressure the major supermarkets and retailers in Japan. The country’s largest retailer AEON has already pledged that it will sell only radiation-free food from now on. On November 24 Greenpeace will be publishing its Retailer Ranking showing the contaminated of fish sold by other supermarket companies. Will they follow AEON’s laudable example? Watch this space.

(Meanwhile, radioactive contamination above government safety level has been found in Japanese rice for the first time. The rice was grown on a farm 60 kilometres from the stricken Fukushima reactors – that’s well outside the government’s 20-kilometre evacuation zone around the plant. Thankfully, the contamination was detected before the rice could be sold for consumption. We can only hope that government agencies can remain as vigilant over other contamination that has been spread so widely across the country.)