Aphanizomenon flos-aquae is a freshwater species of cyanobacteria or Klamath Lake blue-green algae as it is known to health enthusiasts.
AFA blue-green algae is typically sourced from the Klamath Lake, Oregon and is promoted by a number of health advocates and raw food guru’s as a nutrient dense superfood.
Klamath lake blue-green algae is often recommended to increase energy, strengthen the immune system, increase mental performance, prevent infectious disease and support joint health. However, most of these claims are completely unproven scientifically.
Although there have been a small number of studies showing potential health benefits from AFA, there are multiple reliable studies which have now found that this type of blue-green algae contains potent liver and nervous system damaging toxins such as microcystins and anatoxins.
These toxins such as microcystins are also thought to be probable tumor promoters in the body…..YIKES!.
Are AFA Klamath Lake Blue-Green Algae Supplements Toxic?
Microcystin & Anatoxin Contamination
Multiple studies have now found that AFA(Aphanizomenon flos-aquae) Blue-Green Algae sourced from the Klamath Lake contains potent liver, nervous system and kidney damaging toxins such as Microcystins, Anatoxins, and Saxitoxins.
Microcystin toxin has been found in all 16 samples of A. flos-aquae products sold as food supplements in Germany and Switzerland, originating from Lake Klamath: 10 of 16 samples exceeded the safety value of 1 µg microcystin per gram. 
Lack Of Regulation From Manufacturers Of AFA Blue-Green Algae
The above research shows that its not just random batches of AFA blue-green algae that are contaminated with toxins such as microcystins.
The studies also show that we can’t take the word of many manufacturers of these supplements who claim to regularly and intensely test their product, as multiple studies have now found samples of AFA blue-green algae to regularly exceed safety levels of these toxins.
Another study assessing potential health risks from microcystin toxins in blue-green algae dietary supplements found that 85 out of 87 samples of AFA blue-green algae contained toxic microcystins, with a whopping 63 of the samples also found to exceed the safety limit of these toxins.
Many of these products contain Aphanizomenon flos-aquae, a BGA that is harvested from Upper Klamath Lake (UKL) in southern Oregon, where the growth of a toxic BGA, Microcystis aeruginosa, is a regular occurrence. M. aeruginosa produces compounds called microcystins, which are potent hepatotoxins and probable tumor promoters.
Microcystins were detected in 85 of 87 samples tested, with 63 samples (72%) containing concentrations > 1 microg/g. 
Unless the manufacturers of AFA blue-green algae are testing every single batch, there is no way of knowing whether one batch conforms to safety limits for these toxins, whilst the next exceeds safe levels for these contaminants.
Klamath Lake Pristine & Clean?
Manufacturers of AFA blue-green algae regularly claim that the Klamath Lake is pristine, clean and non-toxic, but we know this claim to be false considering the level of research from environmental agencies showing us just how polluted and toxic the Klamath Lake really is.
Microcystins and other toxins aren’t the only contaminants to be worried about when it comes to AFA Blue-Green Algae either. It is now well known that agricultural runoff such as fertilizers, industrial pesticides, and even manure regularly run into the Klamath Lake.
Hardly the pristine and clean lake that its often promoted to be by manufacturers of the blue-green algae supplements.
Conclusion On AFA Klamath Lake Blue-Green Algae Supplements
At this stage from the scientific research, it appears highly questionable whether blue-green algae sourced from the Klamath Lake is even safe for human consumption, let alone before we address the fact that most of the touted health benefits are completely unproven scientifically.
Toxins such as microcystins, anatoxins, and saxitoxins, all have very low dose thresholds for causing serious potential harm to health.
If the manufacturers of these blue-green algae supplements can’t even safely and consistently regulate levels of these toxins in their products, then id suggest that alone is a very serious concern in regards to consuming AFA blue-green algae. These toxins can cause irreparable liver and nervous system damage.
I don’t see any significant reason to consume any level of these microcystins, anatoxins and other toxins that are commonly found in AFA blue-green algae sourced from the Klamath Lake.
The risks here far outweigh any of the potential health benefits in my opinion. Especially
when you can easily obtain the nutrients contained in AFA from multiple other proven safe food sources.
The information in this article has not been evaluated by the FDA and should not be used to diagnose, cure or treat any disease, implied or otherwise.