Microcystins in Blue Green Algae
It is a common fact that most blue-algae species are known to produce toxin, microcystins (MCYST-LR, to be exact). However, it is important to made known a specific species Arthrospira platensis have so far been granted clearence as safe for human consumption in United States, Australia, Japan, Canada and probably EC.
Production of Spirulina as animal feed were largely not regulated in many developing third world countries and as in all likelihood there is always a danger of species substitution and/or contamination of Arthrospira plantensis with other microcystins producing blue-green algae.
While there has been incident where MCYST-LR were detacted in spirulina dietary supplement sample analysed (Gilroy, Kauffman, Hall, Huang and Chu, 2000), MCYST-LR content found in dietary supplement samples were below the regulatory level established by the ODA for microcystins in blue-green algae products which is 1 μg/g.
Spirulina as a whole, has been recognized as GRAS (generally recognized as safe) under the “indented conditions of use” implying that it is “for use as supplement, at levels ranging from 0.5 to 3.0 grams per serving”. Nevertheless, considering that safety level and possible hazards for consumption of spirulina and spirulina-related products have not been established beyond doubt, special precautionary measures would be necessary on the consumption of spirulina products to some segments of the global population at risk to include pregnant women, nursing mothers and people in dialysis and immune-compromised.
Therefore sourcing of spirulina for human consumption should be from countries where cultivation of spirulina are regulated and have stricter regulation.