Radiation contamination found on tea grown in Kanagawa prefecture (Ashigara tea)

Note: This was written in May 2011

Before I post Part II of the Keeping Japan Going series, I thought I should address this 'breaking news' item. I got some questions about the 'contaminated tea leaves' in the news (this has been in the Japanese news for the past few days actually).

It is now tea gathering season in this part of Japan, and it seems that the tea leaves are just now getting tested (I have no idea why they didn't do it earlier by the way.) The tea in question is Ashigara tea, from Kanagawa prefecture...local to me since I'm in Yokohama, the largest city in Kanagawa, as I type this (my mom lives here). Tea here in Kanagawa is grown in a small scale way in several towns and villages. It's not considered to be top-class tea per se, and is often just branded as Ashigara tea even if it's not actually grown in the town of Ashigara. Anyway, levels of radioactive cesium (caesium for Brits and Aussies) above the 500 becquerel limit set by the Japanese central government were found from tea leaves harvested in a total of 5 villages, and tea growers in the entire region have been requested to stop shipments, and the tea growers association has already decided to destroy the contaminated crop. Needless to say they are not happy at all, especially since tea, unlike green leafy vegetables, takes a very long time to grow. (NHK World news report in English.)

Now, why was just cesium detected and not the most often detected radioactive substance, iodide 131? My somewhat educated guess is that the iodide has already deteriorated and dissapated to an undetectable level because of its short lifespan of 8 days. Cesium has a much longer lifespan, up to 37 years I believe. So anyway, that is the situation: if you happen to encounter Ashigara tea from this year (unlikely, because of the shipment stoppage) then it's safer not to use it.

If you're from elsewhere you may wonder if your Japanese tea is affected. If you already have it or it's at your stores, it's not - because remember this is THIS year's harvest we are talking about, which is just starting now. I am sure all tea growing areas are measuring their harvests. In Japan, the major tea growing areas - that grow enough to export - are Shizuoka, the Kyoto area (Uji and so on), and southern Kyushu such as Kagoshima. So far there have been no reports of any problems with tea or any produce grown in these areas, which are further away from Fukushima. (There were earlier reports of some iodide found on green leafy vegetables grown in Kanagawa, though not above safety limits.) So if you are looking forward to new-harvest tea (shincha), as long as you are getting your Japanese tea from reputable sources that clearly state their origin you should be fine. As far as Shizuoka and the Kyoto area are concerned, the recent news that the Hamaoka power plant in Hamamatasu, Shizuoka is in the process of being shut down for precautionary reasons may give a sigh of relief to farmers in the area.

I have also been accused in some quarters of trying to downplay the seriousness of the situation regarding the Fukushima plants. I don't think I am, but I'm not trying to spread panic either. The tea leaf contamination as far as I can tell, based on looking at ongoing measurements of atmospheric radiation (not just on what's reported in the news media) is not from a new radiation leak from the Fukushima nuclear power plants, but from the earlier ones soon after the earthquake, especially around March 15th. (See my previous report about vegetables, and the links at the bottom to various sources of information.) No new incidents per se have occured at the Fukushima No.1 plant as far as anyone can tell from the numbers. Let's hope it stays that way, and that the reactors and spent fuel chambers can be cooled down safely.

I know it's all very scary and disconcerting, but so is stuff like food being contaminated by e.colli or growth hormones or (even worse) purposefully contaminated with melamine or mercury and so on. I firmly believe that we all have to keep constant vigilance and make informed decisions about the things we consume.

On a personal level, my tea-snob mom never bought Kanagawa grown tea anyway, and I guess she's not going to start now. ^_^; (She favors an organically grown tea from Kagoshima at the moment for what it's worth.) (ETA: The tea is from Shimodozono, and not only is it organic, it is grown with no fertilizers of any kind added to the soil - 'tea as it grows in nature'. They also sell conventionally grown tea, so if you want to try the 'natural' tea it's this one (Japanese only page I'm afraid, and I'm not sure if they ship overseas. They ship all over Japan though.)

[Update:] Above-limit amounts of cesium have also been found on some tea grown in Ibaraki, Chiba and Gunma prefectures in the past few days, and these tea leaves have been withheld from the market. These are the same prefectures that had the problems with green vegetables a few weeks ago. So far I have not heard any news of contamination further south or west than Kanagawa. (Please pull out your maps of Japan if you're not sure which prefecture is where.)

Filed under:  tea japan earthquake


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Maki-san, I think it's brilliant you're doing these articles. They're really interesting for starters, and mean we can understand the situation better and make informed choices. It's a great alternative to the rubbish churned out by sensationalist media. Please keep up the good work and enjoy the rest of your time in Japan.

Dear Maki san,

thank you for your comments. I fully agree with you about the Iodine content. With a half life time of 8 days it is most likely gone, plus there had been not noteworthy drinking water contamination in the area.
Being very curious, is there a chance to know the source of the Kagoshima tea?
Additionally I agree shopping food has not changed much for me. I checked the labels before and I do it now. I wanted to know what I eat before and that has not changed.

All the best and keep going!

Sibylle Ito

Lovely, informative article. Thank you for not only saying what tea is no good, but giving a detailed advice on what tea to switch to!

Thank you for the article.

On a personal level I don't think I'll ever be affected by the Fukushima contamination drama due to the strict control of food imports in Singapore but I do agree that it's important not to spread mindless panic over this subject. And yes, e.coli and what they're doing to foods in China scares me 100 times more than the situation in Japan.

God bless you Maki-san for what you're doing for us, you really deserve to be a great name in Japan cause you're not looking just for your good living, i'm impressed cause you care about others life too. Many thanks to you.

Thanks for all of your hard work and information. We'll definitely stay informed and help Japan get back on its feet!

Arigatou !!
Eigo ojouzu desune !
Benkyou ni narimashita!!

In a recent report I read about

Shizuoka, Kanagawa governments oppose radiation screening order for tea leaves


This is certianly worrying.
Is the authority trying to hide something?

Though they argured that

radiation levels in green tea can exceed the legal limit during the production process even if those in raw leaves and final products are below the provisional amount.

It is not convincing at all. Perhaps you have more ideas on what is happening?

They aren't saying tea should not be tested, they are saying that tea leaves should be tested in the state in which they are consumed (dried tea leaves) as well as the fresh tea leaves as they are picked, rather than during the processing stage (aracha). Whether or not this is correct is up to scientists to decide. If the central government disagrees with the assessment of the governors of Kanagawa and Shizuoka we shall see.

Ah.. So I did hear that correctly? Thank you for the link!!!

I was just speaking to my husband Sebastian about this the other day, I'm quite concerned, foremost because I drink copious amounts of Green Tea, and like you mentioned in your other article, do we just leave our trust in the hands of the manufactures, when I think their highest concern is the "bottom line"? The tea we drink now, or which has been bottled already is from a previous harvest?

From my understand of the news, the gov asked them to participate in having their leaves tested, but some refused? What about those who refused (once a bad reputation starts.. like a domino affect, so I understand) but I think they would garner more customers and trust by testing, and only selling the leaves which are unaffected? Yes? I guess the question I have in general is are those leaves which aren't tested sold to "Suntory" or "Itoen" for example?

Yes the tea you are drinking now is from previous harvests, because new tea is just now being harvested. Since you mention Suntory and Itoen I guess you are talking about bottled tea. That was harvested way before...otherwise it wouldn't be in bottles now. ^_^;

What news are you talking about? No one refused to be tested per se as far as I know (or has been reported), they just raised questions about at which stage tea should be tested. Please read my previous comment about that news item.

I really can't tell you to blindly trust anyone. My only advice would be to do your homework, look at past track records of companies, and not to make judgements based on unfounded fear alone.

FWIW, so far the big food producers have been perhaps overly cautious about food from the affected areas. Kagome for instance (producers of canned food among other things) cancelled their contracts for tomatoes from the region, and paid a pittance as compensation to the farmers - even though tomatoes were not measured with above-limits radioactive substances. I don't see any reason why companies like Itoen and Suntory won't do the same, for better or worse.

Hi Maki, thank you for replying, the news was something to the affect of the Japanese Government asking the Green Tea farmers voluntarily to have their leaves tested (Shizuoka I believe), and some refused? but like you said, I Can't see why other large companies won't take the same precautions as Kagome. I could have misunderstood the news I hearing though, I'm still quite rusty with my Japanese ability, I will check though to find out, I will ask my husband I think he mentioned something as well and will give you and update.

Have a fab week!

Maki, do you have any idea how contaminated harvests are destroyed and disposed of? Any information on that would be greatly appreciated.

Hi, I just came back to read your article again....I've made my mind of buying tea from Uji and further South only (better safe than sorry) but today my husband came back with a present - a bag of Shizuoka sencha.
The thing is, I am pregnant. I really don't want to take any risk with radiation. I've told myself that since it has already been imported into Australia, this must be last year's harvest, definitely not this year's tea!

Reading about Shizuoka mayor refusing to bulk-test their tea for radiation is concerning.

Do you have any advice for me? Is it possible at all that our imported sencha is this year's harvest? Thank you!

1. The tea you have is absolutely *not* this year's harvest. This year's harvest is just now being processed and packaged. If your husband bought it at a store in Australia it was shipped out probably months ago.

2. Shizuoka has not, I repeat NOT, refused to bulk-test tea. What they are doing is testing the fresh (unprocessed) tea leaves PLUS the final result, the dried (fully processed) tea leaves. They are not testing the in-between state tea, which is called "ara-cha". Neither the fresh tea leaves nor the final ready-to-drink-state tea leaves have been found with anything near safety limits for any radioactive substances.

Shimodozono ships worldwide - as KEIKO.

I like the Keiko green tea but worried about the contamination. I just asked the Keiko company about my concern but no reply yet...hope they can answer me soon ...

Oh this should be considered in serious! Most of the people used to drink tea or coffee as a refreshment drink! If the government fails to take the needful decision it will affect the whole population! It’s time to act!
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