Cyanobacteria, neurotoxins and water resources: Are thereimplications for human neurodegenerative disease?

摘要

Cyanobacteria are cosmopolitan microbes that inhabit marine, freshwater and terrestrial environments. Under favourableconditions in waterbodies, they can form massive populations (blooms and scums), which present hazards to human andanimal health. Such cyanobacteria often contain a variety of toxic substances (cyanotoxins) that can exist as both cell-associated and free forms in the surrounding water. Some cyanotoxins are highly neurotoxic and act through a variety ofmechanisms. Recent findings of the production of the neurotoxin β-N-methylamino-L-alanine (BMAA) by cyanobacteriain aquatic environments, and of BMAA in brain and cerebrospinal fluid samples of amyotrophic lateral sclerosis andAlzheimer's disease victims, raises the possibility that people may be exposed to waterborne BMAA of cyanobacterialorigin and that this may contribute to human neurodegenerative disease. An understanding of the risks presented bywaterborne BMAA and of available mitigation strategies to reduce this potential exposure is needed.