In a paper published on March 25th, it’s been revealed that watering wheat seedlings with BMAA contaminated water results in uptake by the plant and incorporation of the neurotoxin into the seeds and roots. 

Long suspected, now demonstrated. Watering crops with BMAA-contaminated water results in accumulation of the neurotoxin in the roots and leaves. Pic credit: John Carney 

In shoot samples, protein-associated BMAA was detected after only 1 day and the highest amount was found after 28 days. 

In roots, protein-associated BMAA was detectable after 5 days, peaking after 14 days. Longer exposure did not cause further accumulation. 

There were also large concentrations of free BMAA detected in seedlings watered with 1000 mg/L BMAA. 

The authors commented,

“ little is known about the effects of BMAA on plants, and even less about the risks posed by consumption of crop plants containing BMAA to human health.”

It’s been demonstrated in the laboratory that techniques such as sand and carbon filtration can remove BMAA from water, but these are not routinely used for irrigation water. Even more of a concern are news reports such as the one from 2010 which says, “Murrumbidgee Irrigation says tests on Lake Wyangan have shown the water is suitable for irrigation" in spite of the presence of a toxic algal bloom.

But water is not screened for BMAA in Australia, because quite simply, no test yet exists (we’ve recently submitted a grant to develop one). Most water treatment plants will remove it as a matter of course, but irrigation water is generally not treated before use. 

Of course, we must be cautious because this is only one study and it only measured BMAA content out to 28 days. It did not follow the fate of BMAA after this time, so who knows what remains in the plant by the time it hits our dinner tables.

Also, it seems unlikely that a crop would be watered with BMAA-contaminated water for its lifetime, as algal blooms (and BMAA production) are transient. So if BMAA is incorporated into the plant proteins early in life, it might be gone by harvest, as proteins are broken down and recycled. On the other hand, if the plant is exposed to BMAA close to harvest, then BMAA contamination might pose a risk. 

Cyanobacterial mats in Yellowstone National Park. Pretty but toxic. 

We know from several studies now that consuming BMAA contaminated seafood increases the risk of contracting MND. Indeed, if it's true for consuming BMAA-contaminated flour from cycad seeds, then it follows the same would apply for wheat.

But as the authors state, and I agree, we just don’t know enough yet. But..

"Considering that eutrophication and the climate change will most likely increase the appearance of toxin producing cyanobacteria more research in this field is definitively necessary."

And that’s exactly why we’re here.