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Green Tea Radiation Info


Statement Regarding Japanese Green Tea, the Fukushima Daiichi Nuclear Power Plant, and O-Cha.com.

List of our certificates of radioactivity on individual green teas.

Our base of operations is in Iwaki city, located in the southern part of Fukushima Prefecture.  Green tea is not actually grown in or near Fukushima - it's too cold here, we simply use this as our base for our operations and purchase teas from various areas of central and southern Japan.  From Iwaki, we ship to customers worldwide.

O-Cha.com was greatly affected by the earthquake March 11th, 2011. Among other things, it demolished the interior of our office and destroyed 2 of our 3 main computers. We ceased selling tea on the day of the earthquake. Through numerous aftershocks we cleaned up, expecting to soon continue operations as usual. Unfortunately our office also happened to be located 37km south of the Fukushima Daiichi nuclear plant. While we were never close enough to be affected by a mandatory evacuation, due to prudent concern for our safety from the worsening situation at the time we decided to leave Fukushima temporarily. Temporarily turned into nearly one year.

When it became apparent that fear of radiation would put a serious hamper on our business, we considered shutting down our long established site.  However, we were offered the opportunity to re-establish in Uji Japan with the gracious help of the Tsuen tea shop located there. We moved there, re-established operations, and continued to ship from there through February 2012.


The Current Situation

O-Cha.com resumed shipping once again from Iwaki City in Fukushima in late February 2012 based on the following:

  • First, it's where our office and warehouse is located, and it's also home.

  • While Iwaki city happens to be where we distribute from, all of the green teas we have ever sold have been and continue to be grown and hermetically sealed in airtight packaging by our suppliers at the places where they are harvested - Southern Japan.  In no way has any of our teas ever been exposed to *any* level of radiation or air outside of where the teas were packaged. Our teas have been tested out are AT OR NEAR ZERO becquerels per kilogram - they are completely safe.

  • The radiation levels have never been significantly high in Iwaki. At its peak, the levels were around 1.24 microseverts.  Current daily measuring in the neighborhood of our office averages at 0.14 microseverts - an extremely low level. How low? If you were to fly from Frankfurt Germany to Singapore, you would receive 39 microseverts of natural radiation just by sitting on the airplane. That is more than 200 times the amount of the current radiation levels in Iwaki near our office.  0.2 microseverts is also close to the same level of radiation that exists naturally in Rome, Italy year round.

  • We resumed shipping from Iwaki again because the reality is there is no longer any real reason to be concerned with radiation levels here.


We realize there will be some who will nevertheless not want to buy our products out of a misplaced fear (known in Japanese as fuu hyou higai 風評被害 - damage based on rumor).  We realize there will be some who will try to use our location as a competitive advantage against us. Nevertheless, we will continue to operate our business based on real facts, the primary being this:


We personally consume all of our own products and would never sell any product that is contaminated by chemical, biological, or radiation.  We would discontinue operations before even considering such a thing!


Additional Information


We provide the following information regarding safety standards of green tea and radiation to help you make decisions when purchasing green tea.


First, a few key words to understand...

  • Aracha - Green tea leaves that have been picked, steamed, dried and rolled.  Nearly all of the moisture has been removed. 
  • Seicha - Aracha which is further processed to take out the stems and subjected to the final roasting.  This is the finished product.
  • Becquerel (symbol Bq) (pronounced: 'be-kə-rel) is the SI-derived unit of radioactivity. This is basically the unit used to measure radiation contamination in food.

Standard for radiation in green tea and other food products (dried, processed aracha)


Max becquerels per kilogram (aracha)

International 1000 becquerels per kilogram
USA 1200 becquerels per kilogram
EU 500 becquerels per kilogram
Japan 100 becquerels per kilogram


It is also important to know that the standard of 100 bq/kg was chosen by the Japanese national government for dry leaf (aracha) over that of fresh leaf or infused tea.  This standard was chosen (at opposition to some agricultural interests who preferred the lower readings of freshly harvest leaf) because when tea is contaminated by radiation, dry leaf shows the highest concentration of contamination and also because dry leaf is sometimes ground up for use as powdered green tea and consumed directly.

When dry leaf green tea is infused with hot water, the concentration is reduced by about 10 times. Thus, the standard in Japan for infused green tea is 10 bq/kg.  If one were to infuse this as normally is done when preparing greet tea, any possible contamination would be also be reduced by 10. 

Please note that all of our green teas have measured out at less than 2 bq/kg (the limitation of testing equipment for cesium 134 being around 2 bq/kg) for dry leaf. The only area of concern for us was Shizuoka tea, which, in some but not most areas of Shizuoka, fell above Japanese standards (but were still within International standards) for about a year after the Fukushima incident. We quit selling Shizuoka tea for a year and a half but re-introduced it again based on the facts and our assurance of its safety. Nevertheless, for every Shizuoka tea we sell, we require that it be tested and you will see certificates for each individual Shizuoka tea in the detailed images section.

Certificates of Radioactivity

  • Note 1: While we provide these certificates freely, it's important to understand that unsafe levels of radiation have never been found in Kyoto or Kagoshima areas of Japan where the majority of these teas come from. There are a few teas in Kagoshima which we have yet to obtain an official certificate for but we are working to get these soonest.
  • Note 2: Some of our supplier's names have been intentionally blurred out by us to protect our sources of teas.  However, we keep original files on record.
  • Note 3 - NO! If you order green tea from us and we ship it to you from our location in Iwaki City, Fukushima Japan, it will not be contaminated with radiation because it was shipped from here. The radiation involved is not the kind that seeps through walls, packaging, etc, and as explained above, there is currently less than about 0.12 microseverts of radiation in the air surrounding our facility, this is less than the natural radiation levels of London or Rome. If there were unsafe levels of radiation where we are located, we would not be here!


Oku Midori, Organic Matcha Kaoru, Organic Matcha Kaoru Supreme

Gyokuro except Tsuen, and all matcha except organic Kaoru & Kaoru Supreme, Daily Sencha, Kabusecha

Yutaka Midori, Uji Sencha Miyabi, Uji Green Tea Bags, Fukamushi Sencha Kaoru

Organic sencha Oku Hikari and Oku Yutaka: Certificate #1, Certificate #2

Last, but not least - If, after digesting the above information, you have any fear whatsoever that we would willing live in a radioactive city, that tea we send you could become radiated and harm your health, or that we would throw away our high reputation built over 15 years and sell green tea with harmful radiation in it, it would probably be in both your best interest and ours to find another source for green tea purchases.

Gift certificates