SimplyInfo.org 2017 Report;
Food And Environmental Contamination Related To The Fukushima Nuclear Disaster
Over the last six years understanding risk still remains elusive. Volumes of data, or many times the lack thereof has made understanding risks from the Fukushima disaster both a hot topic and a sense of frustration for many.
Official records tend to put calming the public as their key priority more so than providing useful information. This has caused public distrust and a certain level of public anxiety. We have found that in some places contamination is a minimal or no problem. In other situations it is still quite problematic and even dangerous. Contamination never remains uniform. Over time the radioactive materials migrate through the environment and the food chain. Discovering where they are and where they are not is key to truly understanding risk on an individual level.
Update of 2016 MHLW food data
The MHLW (Japan Ministry of Health, Labor & Welfare) food data has a number of problems. The large volume of testing done on foods of a type and location that are unlikely to be contaminated dilutes the potential findings of contaminated food. The MHLW testing is presented in a less than useful format. Most laboratory data will give a value and an uncertainty factor. This allows the reader to see the value and if that value is below the level of accuracy or when it is above the level of accuracy, the accuracy variance. MHLW is instead providing a value stating is is “less than” an amount but being unclear if those are accurate values as they provide no uncertainty factor. The actual reading is unclear. For much of the testing the “less than” amounts are quite high. For tests run on an NaI detector they will have less accuracy so they can only accurately find radiation readings in the range of above 5-20 bq/kg. A Germanium detector can find contamination amounts below 1 bq/kg. A key piece of information is left out of this data. The run time for the test. In reviewing the provided support documents this is not mentioned. The longer a test is run the more accurate it is. This makes it capable of accurately finding smaller amounts compared to a shorter test run.
The issue of not testing food of concern and instead doing more widespread testing was quite apparent in the 2016 report.
Roughly half of all food tested from Fukushima in fiscal 2016 was livestock meat. Beef has been less of a potential vector compared to other types of food in the years after the disaster.
Testing breakdown for fiscal 2016:
292,647 Total tests conducted across Japan
34,393 Total tests in Fukushima
18.450 Fukushima tests not livestock products
7,397 Fukushima agricultural products tested
258,254 Tests outside Fukushima
Only 2.52% of foods tested were agricultural products in Fukushima.
First half of February 2017:
7348 Total samples
71 Samples that were from Fukushima and were agriculture products
Only 0.96% of February 2017 samples were Fukushima agriculture products.
Known potentially contaminated foods in Japan are rarely or not tested, these include wild vegetables, wild or outdoor cultivated mushrooms, wild game, yuzu, blueberry, persimmons and bamboo shoots.
Food status Japan vs. US
Japan’s official reporting of food contamination is of limited use and reliability. The testing in the US has been of even less value. US FDA did some brief testing in 2011. That was found to be fraught with flaws in methodology. Many of the food products collected in the US soon after the disaster for testing were from the previous year’s agricultural harvest or likely produced before the disaster. There was also no effort to determine the location within Japan that the tested imported food products came from. Testing foods from far flung prefectures and those from before the disaster would be of little use in understanding the actual condition of food safety from imported Japanese products. US EPA did some increased testing of water and milk for a brief period but that was the extent of official testing of the US food supply in 2011.
The FDA finally did fish testing in 2014 but used Alaska’s state program to do the testing. This meant only Alaska seafood was being subjected to testing. For 2016 only 14 fish samples, all from Alaska were tested to represent the safety of the entire US domestic seafood supply. The 2014 US domestic haul of seafood from the Pacific was roughly 4.7 billion pounds. 14 fish is hardly an appropriate screening of the food supply.
The only other US based food testing for radiation has been the FDA Total Diet Study. That also remains a highly flawed program that tells us little of Fukushima’s potential impact on the US food supply.
Isotopes of concern
Iodine 131: Iodine 131 is a relatively short half life isotope. It is produced during a meltdown in large quantities. With a half life of 8 days those large quantities reduce in a relatively short period of time compared to other isotopes. Iodine 131 is a gamma emitter so it is easy to detect with widely available equipment. Both iodine 131 and iodine 129 behave as iodine in the human body, in the environment and through the food supply. Radioactive isotopes of iodine can collect in the thyroid gland causing damage, health problems and cancer. Iodine 131 has a biological half life of about 66 days. This is the time it takes for the percentage of an isotope that collected in the body to clear back out of the body. With most isotopes a percentage collects in the body in certain tissues upon ingestion while the rest is excreted through the digestion process.
Iodine 129: Iodine 129 is a long lived isotope with a 15.7 million year half life. This isotope can be produced in a reactor meltdown. It is a low energy beta and gamma emitter. This makes it more difficult to detect. It is known to be damaging to human health and is rarely if ever tested for by government authorities related to food safety. Iodine 129 in the thyroid has a 120 days biological half life.
Cesium 134: Cesium 134 has a moderate half life of 2.06 years and is a gamma emitter. This isotope is one of the isotopes of concern from a reactor meltdown. Cesium 134 and 137 behave like potassium in the human body, in the environment and through the food supply. Cesium in the human body ends up in the muscle tissues including the heart. This can cause damage and cancers.
Cesium 137: Cesium 137 has a moderate half life of about 30 years. It is a gamma emitter and the isotope most commonly tested for in the food supply by government authorities. Cesium 134 & 137 have a biological half life of 110 days.
Strontium 90: Strontium 90 has a 28.79 year half life. It is a beta emitter. This means that the typical monitoring equipment used to test food samples can not detect it. Strontium 90 is produced both by reactor meltdowns and atomic bomb testing. The biological half life for Strontium 90 is estimated at anywhere between 14 days and 49 years. Due to it being a “bone seeker”, the long biological half life is extremely problematic. It has the potential to cause bone cancer, leukemia and cancers in nearby body structures. The long biological half life along with the low level widespread persistence in the food chain creates a concerning scenario for human health.
Isotopes and what foods they are frequently found in
Iodine isotopes are commonly found in the following foods:
(Iodine 131 is a concern as long as it is present after being released)
Milk, leafy vegetables, tea leaves, some fruits, fish and water
Cesium isotopes are commonly found in the following foods:
(Cesium can find its way into a wide variety of foods, the foods listed have a known high affinity for radioactive cesium)
Blueberries (wild worse than cultivated), mushrooms, tea, wild game, bamboo shoots, persimmon, yuzu fruit, orange (skin), bottom dwelling fish and high up the food chain fish
Strontium 90 isotopes are commonly found in the following foods:
(Strontium 90 can find its way into a wide variety of foods, the foods listed have a known high affinity for Strontium 90)
Milk, tea, beans, wheat, apples, bones of fish
Other isotopes that are known to be of concern but are rarely tested for are isotopes of Plutonium and Americium. US Department of Energy ongoing studies near Amchitka Island show these isotopes were frequently found in the following:
Octopus, kelp, seaweed, urchin and horse mussels
Low level consumption vs. high level consumption & intervention levels
The intervention level in Japan is 100 bq/kg for food. In the US the intervention level is 1200 bq/kg. The EU has a similar intervention level. Intervention levels are only the point where a government will pull food off the market, it is not a promise of complete safety.
Much of the government oriented reporting on contamination in the food supply and the environment look at high level exposures and compare findings to radically high contamination scenarios. This ignores the problem of constant consumption of low levels of radioactive contamination. Any ingestion of the list of isotopes in question creates an insult to health to some extent. The frequency and amounts play a role in the amount of cumulative health damage one actually receives.
High intervention levels may create a false sense of security among the public. The public has a right to know what is in their food and make their own determinations about risk.
Japan citizen testing finds results
The citizen run lab in Iwaki Fukushima has become a reliable resource for independent testing of food and environmental samples. The lab includes the capability to do beta radiation testing, something few citizen labs have.
In a review of their fiscal 2016 testing a some interesting findings were revealed. The lab runs samples brought in by the public so what is tested, is what people in the community are concerned about.
One constant source of contamination was the contents of vacuum cleaners. Either the contents or the bag of contents, depending on the type of vacuum are tested. These are frequently in the 1000’s of bq/kg in contamination. One set of findings from April of 2016 were particularly concerning. A group of ventilation samples, assumed to be from a building ventilation system had cesium readings that ranged from 24,793 to 43,197 bq/kg. The ventilation samples are dated 2011 to March 2016. This is assumed to be the time frame the ventilation system went without cleaning. The set of samples are from Iwaki, Fukushima. Included in the same group was a vacuum cleaner sample take also in March 2016 and appears to be from the same building. The vacuum cleaner contents indicated 53,854 bq/kg of cesium 134/137. 8,000 bq/kg is the limit where something is considered dangerous radioactive waste. Iwaki is not an area that was evacuated at any point during the disaster. It is not clear why the levels in this one building were so extremely high but it does raise concerns about the persistent levels of contamination people encounter in day to day life in places declared “safe”. Some other concerning environmental findings from the lab:
Soil Naraha* Fukushima 14,355 bq/kg
Pine cones Iitate Fukushima 16,269 bq/kg
Soil under eaves trough Chiba** 32,886 bq/kg
*Naraha has been reopened and declared safe for full time residence.
**Chiba is far south of Fukushima, near Tokyo.
The citizen lab also tested a mummified cat and a mummified rat found in Futaba, Fukushima, one of the most contaminated places in the evacuation zone. The cat had 1,415 bq/kg and the rat 3,404 bq/kg. The testing of both was done in a non destructive manner.
Among the foods brought into the lab these kinds of foods were found to be contaminated:
Shiitake mushrooms: Fukushima, Nagano
Bamboo shoots: Fukushima, Ibaraki
Persimmon, mandarin orange, yuzu: Fukushima
Horsetail herb: Fukushima
Bamboo charcoal: Fukushima
Lotus root: Ibaraki
Apricots & loquat: Fukushima
Soil, sand and environmental debris: Fukushima
Mulberry leaves: fukushima
While most of the foods did not have high levels, the reports give a good idea of what items are potentially contaminated in the food supply in Japan, focused on Tohoku and Honshu.
US FDA Total diet study results
US FDA (Food & Drug Administration) released a long overdue radionuclide in food report of the US food supply in 2015. The report provides some useful information but is challenged with a lack of clarity on a number of issues. When a food was obtained or tested between 2006-2014 is not disclosed in this report. This makes it impossible to understand what samples were obtained post Fukushima, if any at all.
The foods tested may not reflect the modern changing US diet. Vegetable testing was limited.
Gluten free, sugar free or other specialty foods were not tested. The diet sampling lacks a good reflection of the diversity of the US population. Ethnic diets are not well represented in what is tested. This shows a gap in both matching the current US demographics and the adoption of a wider variety of foods by the US population in general.
Reading the entire FDA report is useful, our review lists only highlight what foods had contamination findings. The FDA report lacks regional definition in their findings. Are foods purchased in one region or from a certain region more contaminated than others? This is impossible to determine based on the FDA report.
Only a few of the tested items show contamination with Cesium 137. These had moderate levels. Since the TDS screens the full list of foods for Cesium 137 but not all foods are likely to be contaminated with Cesium 137 the limited number of contaminated findings may be a bit misleading. Testing that focused on high potassium foods or those known to be able to uptake considerable amounts of cesium would be likely to give quite different results.
The Strontium 90 findings were more frequent and with low total levels of contamination but this seems to be typical for strontium 90 in the food supply. Allowable levels of Strontium 90 are usually considerably lower than the same for Cesium 137. Since a portion of all consumed Strontium 90 is deposited into bones, these frequent low levels are problematic. Even more so for young children. The number of baby food samples that were found to be contaminated with Strontium 90 were disturbing. These findings lack brand or region data making any effort to find safer baby foods impossible.
Among the Strontium 90 findings were a large number of carbohydrate sources. Grains, beans and the subsequent food products were common sources of Strontium 90 contamination. Apple products, pork products, and processed foods were also notable. The list of foods tested does lean heavily towards carbohydrates and prepared foods. The smaller number of fruits and vegetables did have some contamination findings but it is unclear if more produce testing would show more contamination across produce varieties.
Fukushima environmental concerns and the Olympics
While many town centers in impacted areas of Fukushima prefecture have undergone decontamination efforts, many areas are still quite contaminated. Forests and other areas that are difficult to decontaminate remain untouched. There has also been an ongoing problem of an area being decontaminated only to find it becomes re-contaminated as dust and other materials migrate back in. The findings of the Iwaki citizen lab show how varied the radiation levels in the environment can be. Radiation levels are also highly variable due to collection in certain locations. This makes hot spots develop where contaminated materials collect. Complicating matters are the findings of tiny particles of fused reactor materials and nuclear fuel. These have been found in the evacuation zone and as far away as Tokyo. The amounts and distribution is not well understood.
What makes these materials even more problematic is that they are small enough to inhale yet insoluble. Some of the workers battling the meltdowns at Fukushima Daiichi inhaled these micro particles. Due to the insoluble nature the body can not expel these particles so they continue to reside in the lungs giving the person a constant radiation exposure. Any activity that involves exertion outdoors or kicking up dirt could increase such risk. Without enough data on the distribution of these materials this remains a risk of unknown magnitude.
Ambient radiation levels in Fukushima prefecture have gone down considerably since the disaster. Official radiation levels and actual radiation levels can be quite different. Citizen groups routinely find higher levels than the official readings. While the external exposures may be lower than they were in previous years, an honest documentation of risk is needed so the individual can make their own determination of the level of risk that is appropriate to them.