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Concern has been raised by the fact that BMAA, a neurotoxic compound, can be produced by organisms related to Spirulina -- a common ingredient in dietary supplements, including "green" powders and drinks. Commonly referred to as a blue-green algae, Spirulina is actually a type of cyanobacteria (formerly called blue-green algae) and many cyanobacteria can produce BMAA. However, small studies suggest that dietary supplements with Spirulina are generally safe. Concerns remain, however, about other blue-green algae, particularly Aph. flos-aquae.

Another concern with supplements made from cyanobacteria is contamination with microcystin toxin — a liver toxin, which appears to be common in A. flos-aquae supplements but has also been found in some Spirulina supplements.

Get the details about this in the Greens and Whole Foods Powders and Pills Review >>

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March 23, 2019

I would stay as far away as possible. As a former consumer, I have my own concerns, and yet it would be foolish to be an alarmist over specious facts, so we should just ignore late-breaking research because it seems half baked?... I think not. Just remember that lead and asbestos, as well as tobacco and a littany of products and drugs, were also deemed "safe".

But as the old adage goes, "better safe than sorry":

February 5, 2020

That bit of research you cited gives Spirulina a clean bill of health.

January 4, 2018

I just wanted to add a few more interesting articles about Spirulina and the potential for neurotoxin/bmaa contamination.

October 7, 2018

Both of those 2 articles were written several years ago and may contain outdated information.
When you send links, it would be nice if you included some kind of description about the links, for example year published and written by who, scientist or consumer.
January 2, 2018

Thanks for posting that article, Doug. Oddly, although that study found no contamination issues, it does not seem to include lead among the tested metals. We have found lead contamination in some Spirulina-containing "greens" supplements, as noted in our Greens/Whole Food Supplements Review at However, its possible that lead was from another ingredient.

As noted in our Answer above, Spirulina products have generally been found to be safe in small studies, but we'll keep your suggestion in mind.

January 2, 2018

Here is a Heavy metal analysis in 25 different commercial Spirulina products for human consumption. Unfortunately, this not include cyanobacteria/BMAA testing. I hope Consumerlab can test for cyanobacteria/BMAA in its own testing in the future.

February 15, 2016

Yes well I have grave doubts about Chlorella - projectle vomiting is not a 'detox' reaction in my view- rather a toxic one!

February 14, 2016

A lot of Spirulina is produced on the Big Island of Hawaii...and the ponds are right next to the airport. For me, that raises questions about possible contamination with toxic compounds.
February 19, 2016

Hi Carolyn - As contamination is a known issue with ingredients derived from algae, tests products containing Spirulina for contamination with arsenic, cadmium, lead, mercury and pesticides. You can see results for products we've tested in the Greens Review:
and find more information about potential contamination in the Concerns and Cautions section of the review:

February 19, 2018

What makes you think an airport is a problem? I have never heard humans to get any breathing problems by living near airport. It is the noise that is the problem.

May 29, 2018

Groundwater contamination from fuel and solvents is not uncommon near airports. That would be my primary concern.

October 7, 2018

Good point, for example firefighting foams may contaminate groundwater near airports.

February 14, 2016

What about Chlorella? Is it same concern as Spirulina?

February 14, 2016

Quite a few years ago I had an adverse reaction to Sun Chlorella. About an hour after ingestion I began vomiting violently every few minutes. My blood pressure shot up. I thought I might be having a heart attack and went to the emergency room. After questioning I admitted to eating some leftover brussel sprouts but completely forgot to mention the Chlorella.
I wasn't having a heart attack but the brussel sprouts went into my medical record. Ha ha.
I didn't make the connection until a few weeks later when I again ingested the Sun Chlorella supplement. Just a few minutes later I began vomiting violently. I was driving at the time, and pulled into a parking lot, and spent the next hour vomiting into a garbage bag. Eventually a police car pulled in nearby and observed me for about 20 minutes and then left.
Finally I made the connection, and have studiously avoided Sun Chlorella.
I should note that I've taken both spirulina and blue green algae supplements for years with no problems.
Side note, when I take blue green algae, which is not often, my dreams at night become brighter.
February 21, 2016

Hi Abby - Thank you for letting us know about your experience with this product. Other gastrointestinal side effects have been reported with Chlorella supplementation, which is discussed in the "Concerns and Cautions" section of the Greens and Whole Foods Powders and Pills Review:

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