Biodegradable microbeads are here to (hopefully) cut down on ocean pollution

Tiny plastic microbeads are used in a wide variety of products, from body washes, toothpastes, and face scrubs to paints and fillers. Unfortunately, they’re not great for our environment, and help contribute to the 8 million tons of plastic that ends up in our oceans (and in the stomach of seabirds, whales, turtles, and other marine life) every year. According to estimates, a single shower can result in 100,000 plastic microbeads being flushed down the drain.

That’s where a new project coming out of the United Kingdom’s University of Bath enters the frame. Scientists and engineers at the university have successfully engineered biodegradable cellulose microbeads, manufactured from a sustainable source. These could be used to replace the harmful plastic ones that have been banned in numerous places.

“We’ve developed a continuous process for the production of cellulose microbeads,” Dr. Janet Scott, reader in the department of chemistry, told Digital Trends. “As cellulose comes from plants, nature produces enzymes to break it down, thus the beads are stable in the absence of the enzymes — in personal care products, for example — but will biodegrade in the environment. Depending on size, these might even be broken down by the time they pass through the wastewater sewage plant process. This is the big difference between our microbeads and those made of plastic.”

biodegradable microbeads project 200 microns 2
Nic Delves-Broughton, University of Bath

A big question, of course, is whether the project is scalable. After all, it’s one thing to create sustainable microbeads in a lab; another to do it price-competitively in large quantities.

“Can we scale? Yes.” Scott said, emphatically. “We intentionally developed both the product and process to manufacture the product together, so that there would not need to be any major changes in the process for manufacturing. The process used can easily be scaled up as it is based on continuous flow ‘membrane emulsification.’ We force solutions of cellulose through porous tubular membranes to produce tiny droplets that are swept away by a flowing oil phase. Then we use ‘phase inversion’ to set the beads, recover the beads and recycle the oil and phase inversion solvent.”

Well, that settles it then! The project has been awarded a $1.3 million grant by the U.K.’s Engineering and Physical Sciences Research Council to develop it in for use in cosmetics and personal care products, along with agricultural products like slow-release fertilizers.