GRAND RAPIDS, Mich. (WOOD) — The fight to protect our environment is multifaceted. Climate change, chemical pollution and overcrowding are just a few of the problems we face. Another one is how we handle our trash. A research team from Michigan State University’s School of Packaging has developed a new material to help us cut down our waste.
Reduce, reuse, recycle has been the mantra for decades now. And while we have made major strides in eliminating waste and improving recycling, there is still a long way to go.
According to the U.S. Environmental Protection Agency, the nation’s plastic recycling rate as of 2018 was just 8.7%. That means more than 90% of all manufactured plastic sits in our landfills, is incinerated with the rest of our waste or covers our streets as litter.
A 2022 report from NPR says sorting is a major issue. There are now thousands of different types of plastic, and none can be melted down together. Plus, plastic also degrades after more and more uses, becoming more toxic.
Rafael Auras, a professor and researcher at MSU, believes composting is key to reducing that waste. He has been working for nearly 20 years on a more biodegradable material: a plastic alternative that can be composted instead of recycled.
Sorting is one issue, but food contamination is another. Plastics contaminated by food — whether it is covered with leftover scraps or absorbed grease — require too much time and resources to clean. Instead of being recycled, they are mixed in with other waste.
“Say you are at the farmer’s market, and you are eating something hot. It’s contaminated with food. That material cannot be recycled. Since it is contaminated, the route to disposal is to collect that with organic waste. That material will now go to the landfill,” Auras told News 8.
Instead of dealing with the sorting dilemma caused by different types of plastic, or food contamination that hinders recycling, what if we moved to a new material? One that is biodegradable, so it doesn’t need to be recycled, and one that will break down much faster in a composting system.
The base of the new material is polylactic acid, commonly referred to as PLA. When manufactured properly, the material’s byproducts are completely natural, breaking down into water, carbon dioxide and lactic acid. Plus, researchers already know that PLA can break down easily in industrial composters.
But to make a noticeable impact, the alternative material would need to work in residential compost piles. Currently, PLA requires special conditions, including higher temperatures, to reach that point.
“I remember people laughing (at the thought) of developing PLA home composting as an option,” doctoral student Pooja Mayekar said in an MSU blog post. “That’s because microbes can’t attack and consume PLA normally. It has to be broken down to a point where they can utilize it as food.”
Mayekar has been working with Auras’ lab group and was the lead writer on the lab’s latest findings, published last June in the academic journal ACS Sustainable Chemistry & Engineering.
Research from Auras’ team and the U.S. Department of Agriculture shows it takes PLA about 20 days in an industrial composter to start breaking down. To make it possible for residential compost systems, researchers would need to find a very specific formula that would allow the material to maintain its shape and integrity and then make it quickly vulnerable once it is ready to be discarded. Auras says the key is a starch mix.
“When you have a starch or cellulose, it degrades very fast in a compost pile. We modify the starch in order to then introduce it into the PLA. … (It’s all about finding) that sweet spot where the starch and the PLA can actually coexist,” Auras explained.
The latest research details what they consider the most efficient material they have developed so far, but Auras and his team aren’t stopping there. The next step, besides continuing to fine-tune this latest material, is to develop biodegradable food packaging.
“This is a challenge for the whole industry,” Auras said. “You spend a lot of time growing that food, obtaining that food and the environmental footprint of that product is very high. So, you need to protect the material for a long time, so it is available when you need it.”