First of all, all our extracts have been tested for the main radioactive isotopes - Caesium and Strontium and Uranium. They are perfectly safe and meet all requirements.
That said, an American producer of cultivated(!) Chaga has been spreading rumors online for several years now. He's stating that Asian / (incl. Siberian) Chaga is contaminated with radioactivity due to the Fukushima disaster, early 2011. This company is marketing its own cultivated Chaga as the only reliable alternative.
These statements are complete nonsense. It's just unsubstantiated marketing talk.
First of all, in Russia it is standard to test for radionuclides such as Caesium and Strontium when exporting.
Second, most people are probably unaware of the strict EU-customs procedures during import. American, Japanese and Canadian Chaga was stopped at the EU-borders quite often during the past few years, but not Siberian Chaga. We will explain further on how this is possible.
Third, the jetstream and ocean streams are moving away from the East Coast of Japan towards the Pacific Ocean and the US. Hawaii was e.g. hit by radiation three months after the disaster took place (over 3 times the normal radiation levels) and the American West Coast was hit shortly afterwards. In North-East China (close to Eastern Russia) however radiation levels increased only 1/100.0000th of the normal level.
Look at this official depiction of the fallout deposition (2011 computer model, later updated with environmental samples in 2013).
Dark blue means zero deposition. Siberia is just visible, top left. China is left. Both are unaffected except the most N-East part of Russia. But as you can see a large part of the US and Canada was affected badly. Based on this (and the EU customs reports) our advice is therefore to avoid Japanese, American and Canadian Chaga (and other wild-harvested mushrooms) completely unless they have a test report proving their safety. There is no reason at all to avoid Siberian or Chinese Chaga.
Some German vendors are still using the Chernobyl accident as a reason to avoid E-European Chaga. But considering the life-span of a Chaga-infected tree (max. 20 years) and the date of the event (1986) it is clear that the last Chaga-bearing tree from that time died at least 10 years ago. No Chaga from that time is in circulation. And again - only test reports are proof, unfounded claims on a website are not. Fake news.
A side note: cultivated Chaga as marketed in the US has completely different properties than wild-harvested Chaga and therefore cannot claim any of the effects found during research. It is also not extracted but in fact a biomass product (= mycelium including the grains in which it grows) with a high level of starch. No betulin, different sterols... for further background, have a look at this article or this extensive monograph (scroll all the way down to 'The future of Chaga').