I hope I'll be able to reassure you on this one.
First point: do note that this study was made on *Chinese* spirulina. While not falling prey to the Yellow scare syndrome, I must point out that Chinese spirulina is overwhelmingly harvested in natural lakes and not cultivated in controlled environments. By controlling pH and salinity levels, algae *growers* can actually produce extremely safe spirulina as validated recently as an extremely safe product by the USP governement agency (http://www.ncbi.nlm.nih.gov/pubmed/21793723
More importantly, do note that microcystins are widely present in natural waters (... drinking waters also). As for other widespread/omnipresent natural toxins and heavy metals, the important point is *quantities*.
Concerns over Klamath AFA, another cyanobacteria / blue-green algae, led to establishing maximal tolerables levels of 1 µg/g. When these where established a whopping 63 out of 87 samples of Klamath algae were above that limit [http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1638057/?tool=pubmed
]. On the other hand, even the worst of the samples of this Chinese spirulina are at 163 ng/g, ie., 0.163 µg/g. - and a mean level of 14 ng/g, ie. 71 times less than the public health alert level
Reading scientific articles with no context (usually provided in the full text version though) can lead to getting scared for nothing. The "detectable levels" indicated in the study are frightening at first sight but mean virtually nothing. Scientific and technical progress makes detectable levels increasingly small
Then again, if you have a strong fear of microcystins and want to steer as safe as possible for any level of consumptions, do note that self-purchased spirulina from non-Chinese (or Burmese or Chadian) sources should guarantee a spirulina which is cultivated in a monospecies environment and not simply harvested in a complex ecosystem. Of course, given that you're talking about products enriched in spirulina, you can't be too sure that manufacturers aren't using Chinese spirulina. Why not take the time to write to your favorite brands to ask where their spirulina comes from and to stand by their choice by putting its origin out in the clear (for others). Using harvested spirulina is indeed irresponsible and as a spirulina producer myself (in Laos, no sales in the US) I can't say I'm too happy the authors of this important paper didn't point out these many differences in the abstract instead of providing an empty basis for fear-mongering
Renaud from Spirulinéa
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