Harmful Algal Blooms (HABs) are on the increase globally. HABs occur when large masses of potentially toxic algae develop in freshwater or marine environments. Typically these blooms are fuelled by increasing human pollution of our water resources, most commonly inadequately-treated wastewater, leading to high concentrations of plant nutrients in our dams and rivers. A large percentage of South Africa’s water resources are already impaired by the sustained presence of blue-green algae.
Blue-green algae produce a large variety of toxins, singularly or in combination. Recently it has become apparent that all types of blue-green algae produce an unusual neurotoxin, called beta-methyl-amino-alanine, BMAA. BMAA in nature is only produced by blue-green algae (cyanobacteria). BMAA is neurotoxic and destroys nerve neurons (e.g. Vyas and Weiss 2009).
Research during the past 40 years has sought to link BMAA with motor neuron disease (Amyotrophic Lateral Sclerosis, ALS, Lou Gehrig’s Disease) and Parkinsons Disease (the so-called ALS-PDC, ALS/Parkinson’s Disease Dementia Complex). This research has focussed on three locations in the western Pacific where considerably higher than normal incidences of these diseases occur (e.g. Bradley and Cox 2009). BMAA has been measured in the brains of ALS-PDC cases, but not in control brain tissue, in the aforementioned clusters, as well as in Canada and elsewhere (e.g. Banack et al. 2009). The effect of BMAA in Parkinson’s symptoms has been confirmed by dosing rats with the toxin (Bradley and Mash 2009).