Ultrasound Kills Red Tides

Wikimedia Commons

Let our journalists help you make sense of the noise: Subscribe to the Mother Jones Daily newsletter and get a recap of news that matters.


Dangerous red tides that kill fish and marine mammals and are toxic, even carcinogenic, to humans, might be destroyed using bursts of ultrasound.

Researchers at the U of Hull in the UK experimented with ultrasound on a species of algae that can cause respiratory disease and liver cancer in humans, reports New Scientist.

The team tested three frequencies of ultrasound on Anabaena sphaerica. All worked, though the 1-megahertz band was most effective—probably by bursting the buoyancy cells filled with nitrogen that keep the algae afloat.

Of course, you’ve got to ask what else the sound might be killing.

In response: The researchers believe ultrasound could be targeted to individual species of algae and the resonant frequency of their buoyancy cells. In theory, this wouldn’t damage regular plant cells, which are relatively impervious to pressure waves.

These high frequencies are also absorbed rapidly in water. At 1 megahertz the effective radius is less than 60 feet. That’s good in that it limits the affected zone but bad in that it would be a lot of work to cover a big bloom.

The study also doesn’t acknowledge—as far as I can tell—the fact that when a whole bunch of algae die and sink to the bottom they fuel a bloom of decomposers who suck up all the available oxygen in the water—turning a red tide into a dead zone.

Hmm.

Still, it might be a way to nip a bloom in the bud. Though we still need to tackle all those annoying onshore factors that grow red tides in the first place, like fertilizer and manure run-off from abusively unsustainable agricultural practices.

The paper’s in Applied Acoustics.
 

IT'S NOT THAT WE'RE SCREWED WITHOUT TRUMP:

"It's that we're screwed with or without him if we can't show the public that what we do matters for the long term," writes Mother Jones CEO Monika Bauerlein as she kicks off our drive to raise $350,000 in donations from readers by July 17.

This is a big one for us. It's our first time asking for an outpouring of support since screams of FAKE NEWS and so much of what Trump stood for made everything we do so visceral. Like most newsrooms, we face incredibly hard budget realities, and it's unnerving needing to raise big money when traffic is down.

So, as we ask you to consider supporting our team's journalism, we thought we'd slow down and check in about where Mother Jones is and where we're going after the chaotic last several years. This comparatively slow moment is also an urgent one for Mother Jones: You can read more in "Slow News Is Good News," and if you're able to, please support our team's hard-hitting journalism and help us reach our big $350,000 goal with a donation today.

payment methods

IT'S NOT THAT WE'RE SCREWED WITHOUT TRUMP:

"It's that we're screwed with or without him if we can't show the public that what we do matters for the long term," writes Mother Jones CEO Monika Bauerlein as she kicks off our drive to raise $350,000 in donations from readers by July 17.

This is a big one for us. So, as we ask you to consider supporting our team's journalism, we thought we'd slow down and check in about where Mother Jones is and where we're going after the chaotic last several years. This comparatively slow moment is also an urgent one for Mother Jones: You can read more in "Slow News Is Good News," and if you're able to, please support our team's hard-hitting journalism and help us reach our big $350,000 goal with a donation today.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate