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Questions and Answers about Fishery products (Monitoring for radioactive materials)(Provisional translation)

Q 1. What is the standard value of radioactive materials in fishery products?

A. The Government of Japan has introduced 100 Bq/kg for radioactive cesium in fishery products since 1st April, 2012, while the provisional regulation value, 500 Bq/kg was applied until 31st March, 2012. 

 (Reference)

New Standard limits for Radionuclides in Foods(by Ministry of Health, Labour and Welfare)   

Q 2. How the monitoring for radioactive materials in fishery products is conducted?  

A. To ensure safety of fishery products and to build consumers’ confidence, prefectural governments, in close cooperation with relevant ministries and industries, have implemented monitoring for fishery products on a weekly basis in accordance with the “Concepts of Inspection Planning and the Establishment and Cancellation of Items and Areas to which Restriction of Distribution and/or Consumption of Foods concerned Applies (revised on March 19th, 2013).” The monitoring is mainly targeting fish species which exceeded 50 Bq/kg in last year. If monitoring value is close to the standard, monitoring will be strengthened on the fishery products. 

Because several fish species alter their habitats during their life stages and/or in seasons, the Fisheries Agency is always checking the monitoring results of each prefecture. When high concentration of radioactive cesium is detected in a species, the information will be shared among neighbor prefectures. Then, the prefectures strengthen their monitoring for the species and others which have similar ecology with the species.

A. According to the monitoring results of sea water and marine soil around the Fukushima Dai-ichi nuclear power plants conducted by Ministry of Education, Culture, Sports, Science and Technology (MEXT) and Tokyo Electric Power Company (TEPCO), the concentration of radioactive materials in the seawater is on a downward trend due to diffusion and dilution. 

Detection of a higher concentration of radioactive materials from sea bottom soil does not necessarily lead to a detection of radioactivity exceeding the standard in the fish living in the area. One of the reasons is that radioactive cesium tends to be strongly combined with the clay in the soil, and such combined cesium is not readily absorbed into organisms. 

The monitoring results on marine fishery products show that although 21 % of monitored products exceeded 100 Bq/kg in the period of April to June in 2011, it was decreased to 3 % in the period of January to March, 2013. No samples of migratory species, including skipjack, tunas, salmons, and Pacific saury, have not exceeded the standard. As for surface fish species, such as juvenile sardine and juvenile sand lance, no sample has exceeded the standard since fall 2011, except one sample of halfbeak caught at offshore of Fukushima. Invertebrates including mollusks and crustacean, and seaweed such as wakame and laver also currently do not exceed the standard. 

On the other hand, the monitoring results show that some demersal fish such as flounders and cod have exceeded the standard in some areas, while the number of such samples has been decreasing. The results also indicated the difference among demersal fish species in terms of excess ratio (i.e. the ratio of samples exceeding the standard to total number of samples) of the standard. For example, Pacific cod has exceeded the standard not only in Fukushima but also in the other prefectures, while walleye pollock has exceeded the standard only off Fukushima prefecture. Such difference may be caused by feeding habits and living environment.  

The Fisheries Agency will continue the close monitoring, in order to make the effects on fishery products clearer.

Q4. How are the impacts of the radioactive materials on species in fresh water such as lakes and rivers?

A. Radioactive materials fallen on mountains and lands could be brought into the freshwater environments such as lakes and rivers through rainwater and groundwater. In addition, radioactive materials once settled on land could be blown up by winds again and fallen on the freshwater environment. Freshwater fish may be contaminated by such radioactive materials. Long term contamination in fresh water fish is concerned because freshwater fish need longer time to excrete radioactive materials compared with marine fish. 

The monitoring results on fresh water fishery products show that ratio of samples exceeding 100 Bq/kg to total samples was decreased to 3 % in the period of January to March, 2013 although it was 37 % in the period of April to June in 2011. As for cultured fish, while some oriental weather loach and topmouth gudgeon which are farmed by extensive aquaculture had exceeded 100 Bq/kg, other cultured freshwater fish such as ayu sweetfish, land-locked salmon, and whitespotted char have not exceeded 100 Bq/kg because their feed is controlled. 

The Fisheries Agency will continue the close monitoring since violation of the standard is still detected from some wild fish in rivers and lakes.

Q 5. Do radioactive materials in seawater concentrate and/or accumulate in fish bodies through water and food chain?

A.Radioactive cesium that have been taken from environmental water (seawater and freshwater) and feed is gradually excreted from fish, as in the case of potassium and other non-radioactive minerals. 

Previous studies show that radioactive cesium in marine fish can rise up to 5-100 times higher than that in surrounding seawater (including effects of food chain). So, radioactive cesium concentration in fish may become higher temporarily, due to the concentration of radioactive cesium in seawater, and intake and excretion ability of fish.   

On the other hand, radioactive cesium concentration in marine fish gradually decrease when that in seawater falls because marine fish have effective biological function to excrete radioactive cesium and other minerals from its body. For example, about half of radioactive cesium is excreted in 50 days if the fish is living in the environment with no radioactive cesium. 

However, radioactive cesium exceeding the standard (100 Bq/kg) has still been sometimes detected from several marine fish species such as bottom fish, even though more than 2 years are already passed from the accident. It is assumed that while the concentration of radioactive cesium in such species is decreasing, the speed is assumed to be slow because the fish continues to take radioactive cesium from the environment (e.g. water, organic materials in sea bed, and feed). 

As for freshwater fish, it takes longer time to excrete radioactive cesium compared with marine fish because freshwater fish have biological function to maintain radioactive cesium and other minerals in its body.  

In order to reveal such mechanisms, in addition to the research on radioactive cesium in fishery products, study on radioactive cesium in environment has also been conducted.   

Q 6. Do radioactive materials deposited on the seabed enter into bodies of demersal fish, such as flounders?  

A. Radioactive cesium, that was released by the hydrogen explosion and fell in the ocean, or entered directly from the nuclear power plant into the ocean, gradually moved to the sea bed, while being diffused into and diluted with the large amount of seawater. Radioactive cesium is still detected from sea bed soil around the nuclear power plant. 

However, detection of a higher concentration of radioactive cesium from sea bed soil does not necessarily lead to a detection of radioactive cesium concentration exceeding the standard in the fish living in the area. One of the reasons is that radioactive cesium tends to be strongly combined with the clay in the soil, and such cesium combined with clay is not readily absorbed into organisms. 

On the other hand, radioactive cesium which is not combined with clay is more absorbable into organisms than combined one. This is considered as one of the reasons for fishery products contamination.  

Taking into account the detection of the radioactive cesium over the standard in some bottom fish through the monitoring, monitoring on radioactive materials will be continued for a wide range of marine species, including demersal species such as flounders and cod.  

In addition, the Fisheries Agency will continue to check the results of the monitoring of the sea bottom water and soil conducted by the MEXT, and Ministry of the Environment and TEPCO.  

Q 7. What kind of actions will be taken when radioactive materials exceeding the standard are found from fishery products?  

A. If radioactive cesium exceeding the standard is detected in a sample from fishery products, prefectural governments request distribution restriction on same fish species. To date, the reactions of fishers have been in full conformity with the requests. In case an expansion of contamination is observed (e.g. detection of fishery products exceeding the standard in more than one area in a prefecture), the Director General for the Nuclear Emergency Response Headquarters (Prime Minister) issues an instruction on distribution suspension order of the fishery products.  

To supply safe fishery products to consumers, monitoring of fishery products will be continued.  In addition, the Fisheries Agency will continue to closely cooperate with prefectural governments and industries to strengthen the monitoring. After the nuclear power plant accident, the distribution restriction has been imposed on all the coastal and bottom fisheries offshore Fukushima Prefecture. The fish caught in the area after the accident were captured as samples for radioactive material monitoring, and have not been distributed at markets (except 31 species caught by trial fisheries*). 

 

*In March 2011, Fukushima Prefectural Federation of Fisheries Co-operative Association has decided to stop fishing activities of all the coastal and trawl fisheries off Fukushima prefecture.  From June to August 2012, trial fishery (bottom trawler and octopus pot) was conducted targeting giant Pacific octopus, chestnut octopus and whelk (Buccinum isaotakii) which had been steadily below the standard. The products were boiled and sold on a trial basis. The target species and area of trial fishery have been expanded. Fish species and sea area covered by the trial fishery must be determined after confirming that: 1) the species is not under distribution suspension order, and 2) the levels of radioactive cesium remain lower than the Standard for a certain time period. Coastal pelagic trawlers have been included since March, 2013. 

As of January 1, 2014, following 31 species are  subject to trial fishery: 

Giant Pacific octopus, Chestnut octopus, Japanese flying squid, Spear squid, Swordtip squid, Japanese dwarf squid, Horsehair crab, Snow crab, Red snow crab, Higoromo Shrimp, Botan shrimp, Alaskan pink shrimp, whelks (Japanese whelk, Double sculptured neptune) and other Whelks (Neptunea constricta and Beringius polynematicus), and Thornhead, Greeneyes, Rikuzen flounder, Hilgendorf saucord, Willowy flounder, Anglerfish, Flathead flounder, Roughscale sole, Rosy seabass, Blackfin flounder, Crimson sea bream, Japanese jack mackerel and Pacific barrelfish. 

Kounago (Japanese sandlance (juvenile)) and whitebait

 

The trial fishery products are sold after confirming the radioactivity level of raw and processed (in case of processed products) state by sample inspection by using NaI (TI) scintillation detector. 

The current state of targets and areas of trial fishery and results of sample inspection by using NaI (TI) scintillation detector before selling are publicized at the website of the Fukushima Prefectural Federation of Fisheries Co-operative Association.

 

 

Q 8. How the safety of migratory species such as skipjack, mackerels and Pacific saury is confirmed? 

A.Monitoring results show that migratory species, such as skipjack, mackerel and pacific saury, have not been exceeded the standard. The monitoring for such species have conducted under the cooperation with prefectural governments and industries at the main landing ports on a weekly basis, taking into account the migration of such species. The results have been publicized on the Fisheries Agency’s website in a prompt manner. 

If radioactive cesium exceeding the standard is detected from migratory species, prefectural governments request distribution restriction of the species caught in the area and/or the catch suspension around the area. The Fisheries Agency informs the monitoring results and the request to the coastal prefectures located along the sea areas where such species is expected to migrate. Then, monitoring for the species will be strengthened. 

The Fisheries Agency will continue to closely cooperate with prefectural governments and industries in order to strengthen the monitoring. 

Q 9.What kinds of measures are taken for ensuring the safety of fishery products sold at markets?

A.To supply safe fishery products to consumers, prefectural governments, with close cooperation with relevant ministries, prefectural governments and industries, have conducted monitoring of fishery products which have exceeded 50 Bq/kg in the past and major marine fish species in each prefecture on a weekly basis, in accordance with the relevant policies, including the “Concepts of Inspection Planning and the Establishment and Cancellation of Items and Areas to which Restriction of Distribution and/or Consumption of Foods concerned Applies (revised on March 19th, 2013)” established by the Nuclear Emergency Response Headquarters(Director General: Prime Minister). If monitoring value is smaller, but approximate to the standard, monitoring will be strengthened on the fishery products. 

If radioactive cesium close to or exceeding the standard is detected in sample, fishers stop fishing and shipping of the species, and/or prefectural governments request distribution restriction on the species. In case an expansion of contamination is observed (e.g. detection of fishery products exceeding the standard in more than one area in a prefecture), the Director General for the Nuclear Emergency Response Headquarters (Prime Minister) issues an instruction on distribution suspension order of fishery products. For instance, in some prefectures including Miyagi and Ibaraki prefectures, fishers have stopped fishing and shipping of the fishery products which have exceeded or may exceed the standard in accordance with the request from the prefectural government. In addition, the Director General of the Nuclear Emergency Response Headquarters (Prime Minister) has instructed the governor on distribution suspension order of the fishery product exceeded the standard. 

As for the offshore of Fukushima prefecture, since the nuclear power plant accident, all coastal and bottom fisheries have been suspended. The fishery products caught in the area after the accident were captured as samples for radioactivity monitoring, and have not been distributed at markets (except 31 species which caught by trial fisheries*). Skipjack and pacific saury fisheries, on the other hand, are operated in the Pacific Ocean including offshore of Fukushima prefecture, and the fish may be landed at ports in the Fukushima prefecture. These species migrate through mainly the area far from the Fukushima Dai-ichi nuclear power plant, where effects of radioactive materials are considered to be small. In fact, that is confirmed by the monitoring of these species. 

Measures, including distribution suspension order, have been introduced in the rivers and lakes where radioactive cesium has been detected exceeding the standard. Such information is publicized on the websites of the national and prefectural governments.

 

*In March 2011, Fukushima Prefectural Federation of Fisheries Co-operative Association has decided to stop fishing activities of all the coastal and trawl fisheries off Fukushima prefecture. From June to August 2012, trial fishery (bottom trawler and octopus pot) was conducted targeting giant Pacific octopus, chestnut octopus and whelk (Buccinum isaotakii) which had been steadily below the standard. The products were boiled and sold on a trial basis. The target species and area of trial fishery have been expanded. Fish species and sea area covered by the trial fishery must be determined after confirming that: 1) the species is not under distribution suspension order, and 2) the levels of radioactive cesium remain lower than the Standard for a certain time period. Coastal pelagic trawlers have been included since March, 2013.

 

As of January 1, 2014, following 31 species are subject to trial fishery:

  •  Offshore bottom trawler and octopus pot (29species) 

Giant Pacific octopus, Chestnut octopus, Japanese flying squid, Spear squid, Swordtip squid, Japanese dwarf squid, Horsehair crab, Snow crab, Red snow crab, Higoromo Shrimp, Botan shrimp, Alaskan pink shrimp, whelks (Japanese whelk, Double sculptured neptune, and other Whelks (Neptunea constricta and Beringius polynematicus), and Thornhead, Greeneyes, Rikuzen flounder, Hilgendorf saucord, Willowy flounder, Anglerfish, Flathead flounder, Roughscale sole, Rosy seabass, Blackfin flounder, Crimson sea bream, Japanese jack mackerel and Pacific barrelfish. 

  • Coastal pelagic trawlers (2species)

Kounago (Japanese sandlance (juvenile)) and whitebait 

The trial fishery products are sold after confirming the radioactivity level of raw and processed (in case of processed products) state by sample inspection by using NaI (TI) scintillation detector. 

The current state of targets and areas of trial fishery and results of sample inspection by using NaI (TI) scintillation detector before selling are publicized at the website of the Fukushima Prefectural Federation of Fisheries Co-operative Association.

 

     →Website of Fukushima fisheries association.(Japanese only)

 

(Reference)

 

Q 10. How the safety of fish which I caught could be confirmed? 

A. If you are uncertain about the safety of the fish caught by yourself, please check the monitoring results of the same species or species living in the same area, published on the prefectural governments’ and/or

    the Fisheries Agency’s websites. If the area you caught the fish is close to the area where radioactive materials exceeding the standard have been detected, distribution is restricted and/or fishery targeting such

    species is suspended, please consult with relevant prefectural governments.

 

    To supply safe fishery products to consumers, prefectural governments, with close cooperation with relevant ministries, prefectural governments and industries, have conducted monitoring of fishery products

    which have exceeded 50 Bq/kg in the past and major marine fish species in each prefectures on a weekly basis, in accordance with the relevant policies, including the “Concepts of Inspection Planning and the

    Establishment and Cancellation of Items and Areas to which Restriction of Distribution and/or Consumption of Foods concerned Applies (revised on March 19th, 2013)” established by the Nuclear Emergency

    Response Headquarters (Director General : Prime Minister). If monitoring value is close to the standard, monitoring will strengthen on the fishery products. The results have been published on the prefectural

    governments’ and/or Fisheries Agency’s websites.

 

Q11. How does the standard apply to dried seaweed and fish?  How about dried food products, such as dried wakame seaweed and hiziki seaweed, which are normally  consumed after being brought back to their original condition by soaking in water? 

A. Dried food products which are consumed as they are, such as dried laver, dried sardine and dried squid, the standard applies for both before and after processing, that is, as raw materials and as dried products. 

    On the other hand, as for dried food products which are normally consumed after being brought back to their original condition by soaking in water, such as Konbu seaweed, dried wakame seaweed, dried

    hiziki seaweed, dried cod and dried sea cucumber, the standard applies for both before processing and after being brought back to their original condition.

Q12. What is the labeling rule on production area of fishery products caught in the Pacific Ocean off eastern Japan?

A. In response to the growing interests of consumers in labeling of fishery products on production area, the Fisheries Agency issued the notice on 5th October 2011 to industries and prefectural governments

     about promotion of production area labeling which puts more focus on clarification of the name of the production area with finer scale classification. 

 

     Finer scale classifications for migratory spices are as follows:

     1 “北海道・青森県沖太平洋” (Offshore of Hokkaido and Aomori. “北海道青森沖太平洋” or ”北海道青森太平洋” is also acceptable.)

     2 “三陸北部沖” (Offshore of Northern Sanriku)

     3 “三陸南部沖” (Offshore of Southern Sanriku)

     4 “福島県沖” (Offshore of Fukushima)

     5 “日立・鹿島沖” (Offshore of Hitachi and Kashima)

     6 “房総沖” (Offshore of Boso Peninsula)

     7 “日本太平洋沖合北部” (Northern Pacific off Japan. “日本太平洋沖北部” is also acceptable.

 

(Reference)

 

Q13. What is the current situation of import restriction on Japanese fishery products?

A. Immediately after the earthquake, many countries introduced import ban to Japanese fishery products. Although some countries including China and Russia have introduced import ban to fisheries products

    originated from part of Japan, other countries allow import from Japan subject to observance of the standard or confirmation of origin. In addition, several countries, such as Canada and New Zealand, do not

    introduce any import restriction.

 

    The Fisheries Agency has informed government officials and consumers in foreign countries about Japan’s effort to supply safe fishery products. Through the ap proaches, the Fisheries Agency has continuously

    requested import countries to lift or relax the imposed import restriction.

Contact Us

For more information
 About inspection on radioactive materials in fishery products:
  Resources and Environmental Research Division,
  Fisheries Agency of Japan
  +81-3-3502-8487

 About radioactive materials:
  Research and Technological Guidance Division,
  Fisheries Agency of Japan
  +81-3-6744-2373

 About distribution of fishery products:
  Fisheries Processing Industries and Marketing Division,
  Fisheries Agency of Japan
  +81-3-3591-5613

 About safety of fishery products:
  Fish and Fishery Products Safety Office,
Food Safety and Consumer Affairs Bureau,
Ministry of Agriculture, Forestry and Fisheries
+81-3-6744-2105

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