In the SKLM opinion on algal toxins from 10/11 April 2003, the Commission expressed its concern that algae-based food supplements may be contaminated with significant levels of microcystins. The SKLM pointed out that there is a need for clarification with respect to their toxicology and the exposure situation. The German opinion was adopted on September 28 th 2005, the English Version was agreed on June 15 th 2007.
Preamble
Particularly products from the algae species Aphanizomenon flos-aquae (AFA) in the form of powders, pills, capsules or tablets are advertised as food supplements in the internet, in printed media and non-scientific publications. They are claimed to have positive health effects, especially for children with an attention deficit hyperactivity disorder (ADHD). However, there is no scientific evidence to support these claimed benefits. According to the current state of knowledge, AFA algae marketed in Europe originate from Upper Klamath Lake, Oregon, USA.
If AFA algae grow together with other blue-green algae (cyanobacteria), the latter may be present as contaminants in AFA algae products. One blue-green algae species, Microcystis aeruginosa, forms microcystins which are cyclic heptapeptides that have been proven to damage the liver of humans and animals. Although only an inadequate number of samples have been investigated so far, the results indicate that from the more than 60 congeners, primarily microcystin-LR (approx. 90%) is present in AFA algae pro-ducts. The toxicology of microcystin-LR has been investigated in the greatest detail; however, the data base on this congener is still incomplete. There are still almost no data available on the other known congeners. Therefore, the present opinion addresses only microcystin-LR. A detailed description of the available data is given in the Annex (www.dfg.de/sklm).