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Plastic is everywhere, and hardly anyone can get through a day without using it.
Mass-produced and mass-consumed, plastics generate mountains of trash in landfills, littering public areas and fouling the ocean — partly because much of it isn’t practical to recycle.
Los Alamos National Laboratory is part of a consortium developing a technology to rapidly break down discarded plastic at the molecular level into components that can be used to create other materials, such as nylon.
The year-old research and development effort has been dubbed BOTTLE. The program was launched in November.
Early research has led to identifying enzymes that can biodegrade plastic noticeably within several days, versus the several hundred years it normally would take for the material to decompose.
Now the teams want to accelerate the decomposition, because breaking down the plastic in days is not nearly fast enough, lab scientist Taraka Dale said.
“So what we’re shooting for is really observable changes and degradation in a matter of, ideally, hours,” said Dale, who leads the lab’s BOTTLE program. “So that you can, in theory, put this in an industrial process eventually.”
The process would be fairly straightforward for users, she said.
A vendor would grind up plastic trash and load it with the enzymes into a tank partially filled with water.
The enzymes would break down and dissolve the plastic into the liquid. They would then transform the molecules into polymers for higher-grade products, such as carpets and clothing.
Dale likened it to dismantling a brick house, and instead of simply reusing the bricks, you turn them into boards for a different purpose.
The company could sell the raw material to a manufacturer, Dale said.
This conversion of throwaway items and scraps into higher-quality goods, such as fabrics, would be “upcycling,” she said.
That’s in contrast to downcycling, when plastics are mechanically processed and put into lower-grade products, such as trash bags.
It might take a decade before this technology can be applied in the real world, Dale said.
“I’d love to say we think it could be sooner, but there’s a lot of science still to do,” she said.
With the growing plastic waste problem, scientists working on the project feel driven to make headway as soon as possible, she added.
Plastic production has skyrocketed since the end of World War II, creating vast amounts of cast-off materials that are extremely slow to decompose.
A plastic beverage bottle takes an estimated 450 years to biodegrade. A solid plastic object such as a toothbrush needs 500 years. A straw won’t break down for 200 years.
A study published last year by Science Advances estimated that in 2016 the U.S. generated the most plastic waste in the world at 42 million metric tons and also put the most plastic pollution into the ocean — an estimated 1.1 million to 2.2 million metric tons.
Plastic trash in the ocean can add to the floating, sprawling patches of garbage that resemble islands. The more detrimental effect is below the surface, with the plastic killing fish and marine mammals that ingest or become ensnared in it.
In New Mexico, plastic waste contributes to litter strewn along roadsides and in parks, forests and arroyos. State health and transportation managers have described the state’s litter problem as chronic.
And of the plastic trash that is disposed of properly, only a portion can be recycled.
Two of the seven basic types of plastic are marketable enough to recycle, and the others are either too low-grade or are mixed with toxic chemicals that render them difficult to reuse, said Randall Kippenbrock, executive director of the Santa Fe Solid Waste Management Agency.
One of the desirable types is PET, the clear plastic used in beverage bottles, and the other is high-density polyethylene, used for milk jugs, shampoo bottles and other household containers, Kippenbrock said.
Those plastics are sold to mills and vendors in the Southeast, he said.
But plastic wrappers, shopping bags, cups, squeezable bottles, Styrofoam, loose scraps and anything that’s soiled are weeded out and sent to the landfill.
“There’s really not a market for those,” Kippenbrock said.
The discarded plastic waste makes up only 0.5 percent of the 11,000 tons of trash, including cardboard, metal and paper, that the Buckman Recycling Center receives in a year, he said.
Still, that adds up to 550 tons of plastic that gets passed to the landfill. And that’s just the recycling center’s rejected materials and not the plastic trash going directly from households to the dumpsite.
Kippenbrock said someone from the lab talked to his regional recycling group about the volume of their waste a couple of years ago.
He believes it probably was related to this research project.
“The regional group that I’m part of is very much in favor of supporting LANL and what they’re trying to accomplish,” Kippenbrock said.
Kippenbrock said he hopes the new technology would be applied to the lower-quality, less desirable plastics because those aren’t being reused.
The consortium’s BOTTLE webpage shows the technology could be used on a wide array of plastic products, including items now deemed nonrecyclable.
The list also includes textiles, fibers, foams and various food and beverage packaging.
Conservationists contend recycling has had limited success in reducing trash flow because it’s cheaper to make fresh plastic, made of oil and hydrocarbons, than repurpose discarded plastic.
Dale said that’s why increasing the plastic’s grade is important — it makes recycling more profitable.
The consortium is made up of five national labs and five universities. The National Renewable Energy Laboratory is the lead entity.
Each plays a unique role.
For instance, Oak Ridge National Laboratory in Tennessee looks for new micro-organisms. Argonne National Laboratory outside Chicago employs computer modeling to identify new building blocks for polymers.
Los Alamos’ key contribution is its “smart microbial cell technology,” Dale said.
It can test an enzyme’s effectiveness in breaking down a plastic by fluorescent color-tagging the molecules the plastic is shedding, she said. The more molecules it throws off, the faster it’s degrading and the better the enzymes are working.
The system can screen as many as 100,000 variants in one experiment, versus the one to 100 that other labs were testing at a time, she said.
“It really gives us a chance to do things truly orders of magnitude faster,” Dale said.
Dale said she thinks the consortium’s research will coincide with the work of other scientific teams, and that the widespread public interest in reducing plastic waste will provide an impetus to tackle the problem.
“It may have the potential for really big impact,” Dale said of the larger effort. “And I expect BOTTLE to be a part of it.”