Science

To remove microplastics from drinking water ... just add okra?

To remove microplastics from d...
When it comes to removing plastic microparticles from water, okra polysaccharides have been shown to be at least as effective as potentially more harmful chemicals
When it comes to removing plastic microparticles from water, okra polysaccharides have been shown to be at least as effective as potentially more harmful chemicals
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When it comes to removing plastic microparticles from water, okra polysaccharides have been shown to be at least as effective as potentially more harmful chemicals
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When it comes to removing plastic microparticles from water, okra polysaccharides have been shown to be at least as effective as potentially more harmful chemicals

If you've ever eaten okra, then you'll know that the stuff can be pretty … gooey. According to new research, that quality could allow a compound from the plant to be used in a less toxic method of removing microplastics from drinking water.

It's an unfortunate fact that tiny fragments of plastic pollution are now spread throughout the world's waterways. The health effects of ingesting those fragments themselves are still not fully known, although one danger lies in the fact that the particles could absorb pollutants from the environment, then pass those pollutants on to us.

In order to remove plastic microparticles from municipal water supplies, water treatment plants typically add chemicals known as flocculants to the water. These form into clumps which the particles stick to – when the clumps are subsequently removed from the water, they take the particles with them.

Unfortunately, flocculants such as polyacrylamide can themselves become toxic under certain conditions. Seeking a safer alternative, Dr. Rajani Srinivasan and colleagues at Texas' Tarleton State University looked to compounds extracted from several food-grade plants.

After some experimentation, it was found that polysaccharides from okra paired with those from fenugreek worked best at removing microplastics from seawater, while those same okra polysaccharides paired with those from tamarind were best for use on freshwater.

All in all, depending on factors such as the ratio of the polysaccharides and the water source, the plant-based flocculants performed either as well as or better than polyacrylamide. And importantly, they could be used in existing water treatment plants, without any alterations to the facilities or processes.

The scientists are now investigating how well other combinations of plant-derived polysaccharides will work on specific types of plastic microparticles, in water from a variety of sources.

Source: American Chemical Society via EurekAlert

4 comments
4 comments
TechGazer
Can farming of okra be scaled up enough to meet the demands of water purification without significantly raising food prices? This may have to wait until they can breed or engineer microorganisms to produce the polysaccharides from waste cellulose or maybe from CO2 and sunlight.
windykites
Do they not use filters to remove particles?
pmshah
Flocculant as far as my chemistry knowledge goes is an additive to settle suspended impurities in a colloid or water. Like adding common alum to turbid monsoon water to clarify it with mud settling at the bottom when left undisturbed. Of course this is in English and it may mean something different in American
Karmudjun
Farming okra is easy and labor intensive at the same time. The damn plants just grow and grow all through the warm months producing a crop of the delectable pods every two days. I don't know how mechanized farms harvest the seed pods, but to walk the rows in summertime and avoid the scratchy plant leaves while cutting through the tough stem of the seed pod is a labor of love for the gourmand. This is absolutely scalable in arable locales.

Flocculant is a chemistry term used properly in this article - yes, they are added to assist in removing any precipitates from the solution that contains them. Good to know my gumbo thickener can help remove microplastics. I guess eating the okra isn't going to help remove microplastics from my body though....digestion rapidly manages the sugars.