A medical microbiologist who lives beside the Lower Vasse River has raised concerns about potential toxin producing organisms that have been linked to neurological disorders.
Dr Andrew Dickie said he became concerned when the river bed dried up and dust started to blow around.
"My main worry is not the cyanobacteria [blue green algae] that irritates skin or kills pets it is the ones that have been associated strongly with motor neuron disease, Parkinson's and Alzheimers," he said.
"There is a lot of scientific evidence that they very probably are."
Dr Dickie collected a sample of a black algae which has been sitting in a sealed jar in his home, it is still growing and now appears to be blue green algae.
He as not been able to get the sample tested to see if the algae contains beta-methylamino-L-alanine (BMMA) the toxin which has been associated with motor neuron disease.
"They have done studies to find out how they might cause the degenerative diseases, and it is fairly well established that BMAA gets into the brain and the body mistakes it for another amino acid called serine," he said.
"It incorporates BMAA into proteins in the brain, but it is the wrong amino acid it is not the right one.
"That causes problems, it accumulates in the brain, builds plaque and kills neurons, there is a lot of evidence that the toxin does that.
"I do not know if anyone has tested for the toxin BMAA in the river but it is highly likely that it is there, up to 85 per cent of cyanobacterial species will produce toxins including BMAA."
Research into BMAA exposure and neurodegenerative diseases
Macquarie University professor of neurosciences Gilles Guillemin has been researching the link between BMAA and motor nuerone disease for the past six years.
He coauthored a report Is Exposure to BMAA a Risk Factor for Neurodegenerative Diseases? A Response to a Critical Review of the BMAA Hypothesis with several international researchers from around the world.
The report was published in Neurotoxicity Research in February this year.
The researchers found that while gaps remained in the literature, there was an 'increasingly large body of data from multiple independent labs using orthogonal methods that provided increasing evidence that chronic exposure to BMAA may be a risk factor for neurological illness.'
Professor Guillemin said they were trying to understand what BMAA's and cyanotoxins do to human health.
"What we found was very interesting and scary, the main cyanotoxins produced by cyanobacteria called BMAA can propagate between brain cells," he said.
"That is the most important discovery we made."
Professor Guillemin has been working in the Riverina area of NSW where they had seven times the rate of motor neuron disease.
"The big river and lakes over there are always full of blue green algae and cyanobacteria," he said.
"I was collecting samples from people living over there and looked at cyanotoxin in pesticides and metals as well, anything linked with agriculture."
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Professor Guillemin said blue green algae occurred more every year because of rising water temperature and the altercation of sulfate and phosphate used in agriculture that fed the algae.
"More food and more heat and they are very happy, which means you get more algal blooms every year," he said.
"The United Nations just put a study out about that because it is becoming an increasing problem around the world, it is an issue."
While the Department of Water and Environmental Regulation are testing the water quality in the Lower Vasse River fortnightly, Professor Guillemin said the technology did not exist yet to test for BMAA.
"I am developing a kit at the moment that will be able to do that," he said.
"In BMAA the cyanotoxins are so small they can go everywhere in the food chain, in plants, you can actually breathe them.
"One of the risks they found is that you can actually breathe them like aerosols.
"In France, if you live near a lake which has blue green algal blooms you have increased risk of developing motor neuron disease because you breathe in little droplets with the toxin.
"It gets into your respiratory system which is a highway to your brain."
Professor Guillemin said further studies were needed to fully prove the link between motor neuron disease and BMAA.
"There is something clearly there but you have to prove it," he said.
Water testing in the Lower Vasse River
A Department of Water and Environmental Regulation spokesperson said water quality monitoring was undertaken fortnightly in the Lower Vasse River at three sites over the algal bloom season from November to May and then fortnightly throughout the year at two sites.
"A permanent data logger that measures oxygen, salinity and temperature every 10 minutes has also been installed at one site downstream of the causeway bridge," the spokesperson said.
"The department has undertaken sampling in the Lower Vasse River fortnightly over the algal bloom season (November - May) since 2000 and fortnightly over the entire year at one site since 2006. Monitoring has not stopped in this time.
"The main species of potentially toxic algae observed in the Lower Vasse River since 2020 have been cyanobacteria (dominant species Microcystis,Anabaenopsis and Anabaena spp).
"Some Cyanobateria can be toxic and therefore warning signs are installed along the banks of the Lower Vasse River.
"Toxins are not always produced by cyanobacteria, it depends on actual species and the environmental conditions and toxicity levels can vary over time.
"The two species of cyanobacteria mentioned may produce a toxin called microcystin which affects the liver. Cyanobacteria may also cause skin irritation with contact."
The spokesperson said DWER had collected a sample of the black algae and that it was commonly seen in the southwest and Vasse estuary.
"This species is not a known toxin-producer in Australia," the spokesperson said.
"The department is able to test that sample depending on sample integrity, providing qualitative assessment.
"A Phytoplankton Sampling Kit, with instructions, can be requested by contacting the department."
WA Health spokesperson the Department of Health has received fortnightly phytoplankton water sample results for the Lower Vasse River since December 2020.
"Direct contact with or consumption of any algae may cause an adverse health effect," the spokesperson said.
Vasse MLA Libby Mettam said for too long, multiple agencies have tried to manage different parts of the Vasse River and the surrounding Geographe waterways and drainage systems and it simply wasn't working.
"The health of the river is suffering as all the different agencies attempt to manage sections in different ways, the various committees established to deal with it have not come up with a cohesive plan and it's having wide-ranging implications beyond the river.
"Action on the river is now urgent and overdue.
"A 2013/14 independent review of Busselton Waterways identified the Busselton Drainage System as a major contributor to the degradation of the Vasse Wonnerup Wetlands and the pollution of Geographe Bay.
"Unfortunately, seven years on, many of the issues he identified still haven't been resolved and the solutions he posed have not been implemented.
"It's very clear that the management and the responsibility for Vasse River and the surrounding drainage and waterways needs to be consolidated and undertaken by one agency to ensure there's a uniform approach and ultimate accountability.
"The Liberals WA will ensure that consolidation and transfer of responsibility is given to one agency as a priority, if elected, to ensure we aren't going round in circles trying to fix these issues in another seven years' time."