The article in Feedback detailing things we did not know about algae, as set forth in a book by Gillian McKeith, did not mention that eating blue-green algae on a regular basis could also connect you with something rather different from "messages of harmony and peace" (17 December).
Blue-green algae - properly called cyanobacteria - are able to produce a range of very powerful toxins, which pose health hazards to humans and animals and can result in illness and death.
Cyanobacteria can form excessive growths at certain times of the year - blooms, often forming thick scums on the shoreline. Such cyanobacterial blooms and scums have recently attracted public attention but have been around for a long time, with records of them dating back to the 12th century.
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