Study warns against sale of ‘toxic’ algae supplements

By Nathan Gray

- Last updated on GMT

Study warns against sale of ‘toxic’ algae supplements
The sale of algae supplements containing A. flos-aquae is ‘highly questionable’ warn researchers, as they identify toxins in every commercially available product in Germany.

Researchers have warned against the sale of organic algae supplements containing the algae strain Aphanizomenon flos-aquae​ after a samples of every commercially available supplement available in the country were found to contain potentially dangerous toxins.

Led by Professor Daniel Dietrich from the University of Konstanz, Germany, the research team assessed levels of toxins and the potential cytotoxicity of 18 commercially available algal supplements, finding that those containing the algae strain Aph. flos-aquae​ contained questionable levels of microcystin (MC) – a cyanotoxin that can be harmful to humans, plants, and animals.

“The analysis for the presence of cyanobacterial toxins (MCs, nodularins, saxitoxins, anatoxin-a and cylindrospermopsin) encompassed only algae dietary supplements marketed in Germany and thus only the three main types of algae generally used for the production of dietary supplements, i.e. ​Aph. flos-aquae, ​Spirulina and ​Chlorella,”​ said the researchers, writing in Toxicology and Applied Pharmacology​.

“Analyses demonstrated the absence of nodularins, saxitoxins, anatoxin-a and cylindrospermopsin in these products, whereas all ​Aph. flos-aquae based products and mixtures thereof were positive for MC contamination,” ​confirmed Dietrich and his team.

Considerable contamination

The researchers said their analysis ‘clearly demonstrated’ that a high proportion of the algae dietary supplements available on the German market “is contaminated with considerable, but varying amounts of MCs.”

“Moreover, cytotoxicity analyses suggest that additional components are present that have the potential to induce fulminant adverse effects in consumers,”

“In light of the findings, the distribution and commercial sale of Aph. flos-aquae products, whether pure or mixed formulations, for human consumption appear highly questionable,”​ Dietrich and his colleagues warned.

As a result the researchers argue that only the prohibition of these products for sale on the national and international markets – in combination with strict monitoring by health authorities – will protect consumers from serious acute as well as chronic adverse health effects.

Source: Toxicology and Applied Pharmacology
Volume 265, Issue 2​, Pages 263–271, doi: 10.1016/j.taap.2012.10.005
“Toxin content and cytotoxicity of algal dietary supplements”
Authors: A.H. Heussner, L. Mazija, J. Fastner, D.R. Dietrich

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Consumers must come first

Posted by Andrew Patterson,

I agree with you that there are a lot of unsupported health claims put out by various MLM companies selling AFA, just as there are a lot of unsupported health claims put out by most MLM companies selling all sorts of things. This is human nature and most of these claims are best ignored! And of course there are MLM companies selling spirulina and chlorella who make unsubstantiated claims as well.

The question is not whether a food substance contains toxins -- most foods do, especially wild ones -- but whether those toxins are in low enough concentrations to be safe. As Dr Scoglio is saying, there are set limits to toxins for most foods, and provided those toxins are below those limits, they are safe to eat. As far as I am aware, there are established safe limits for MC -- otherwise the AFA is not legal to sell. So the focus should be exposing brands of AFA that have an MC concentration above the safety limit, rather than making blanket statements on AFA in general?

I did not know Dr. Dietrich has a conflict of interest because he is promoting his patented test, and I think the fact the Dr. Scoglio, who to be fair to him freely admitted to having a conflict of interest, has offered to work with him is a positive step. Dismissing these conflicts of interest as "personal attacks" is not helpful to the consumer, who after all is the most important person in this equation. Unlike Dr. Scoglio, Dr. Dietrich did not put his conflict of interest on the table.

So please please Dr. Dietrich, for the sake of consumers, take up Dr. Scoglio's offer and do the necessary studies to bring this to a conclusion. It may mean the withdrawal of certain brands of AFA, or it may dismiss the validity of your test, but one way or the other consumers must come first -- not products and patents.

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Conflict of Interest from AFA company employee

Posted by Al G. Lake,

Scoglio wants to dismiss Dietrich's findings as Conflict of Interest since Dietrich has done a lot of work on AFA and MC testing methods. Scoglio admits he works for a company which makes AFA supplements. I'm familiar with much of the history of Cell Tech and Klamath Blue Green Algae. Decades of unsupported health claims, various Multi-Level Marketing companies, and independent discoveries of toxins which have indeed harmed and apparently killed humans underscore the need for caution and skepticism regarding claims of AFA promoters.
While I appreciate that AFA businesses in the Klamath Falls region would like to be profitable, it appears that spirulina and chlorella are much safer if one wants to eat algae. If an AFA company wants to show otherwise, they should do real, responsible studies to show that AFA is as safe and more effective than the other algaes. Making personal attacks on a scientist and dismissing his findings as 'conflict of interest' because he's an expert are weak arguments.

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Conflict of Interest? True science or self-interested manipulation?

Posted by Stefano Scoglio,

Dietrich has been trying to prove AFA's toxicity for more than 10 years now, without ever managing to do so. If one wants to prove the toxicity of a substance, the method is to administer the substance to guinea pigs and see the effects. The only study thus done, where AFA algae containing 10 times the allowed content of MCs was used, showed that no adverse effects were produced.
It is not true science to take the criterion adopted for inert water, 1 mcg./lt., and adopt it for substances like algae that contains many substances with the ability to inactivate MCs (MCs works through oxidation, so most antioxidants inhibit MCs). Recent studies done on fish, showed that while the fish was adversely affected by the intraperitoneal administration of 10 mcg. of MC (about 5 times the allowed daily limit), the oral intake of the whole algae containing the same amount of 10 mcs. of MCs did not produce any adverse effects.
Why does Prof. Dietrich, in over 10 years never bothered to do an animal study on AFA toxicity, and only keeps only analysing the MCs content of the algae? Because Dietrich is the holder of a patent on one of the different methods used to test for MCs; that is, he is in an evident conflict of interest. Moreover, even in his study, the majority of the brands he analysed were within limits. That means that the problem of contamination is a problem of contamination to be controlled, in the same way aflatoxins have to be controlled for wheat, eggs for salmonella, and micotoxins in apples. Or do you think we should ban wheat, apples and eggs?
I work with a company that manufactures AFA algae, we control every lot and we never found a level of MCs above 0.85 mcg/gr. Having said that, much higher quantities of MCs as present in the whole algae, and not extracted and injected, would not do any harm. I have used AFA algae for myself and my family for about 20 years now, and I am in perfect health. Giving too much credit to Dietrich's unscientific because un-experimental studies risks creating serious reputational damage, that my company is ready to tackle in any legitimate seat. If Dietrich is so sure of its conviction, why doesn't he step up its research with an animal study? We are ready to collaborate and even fund such a research. But I doubt he will accept. I am available to provide much more detailed information than I could provide here.

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