Why Bioplastics Are Not (Yet) the Solution to Plastic Pollution
Single-use plastics, while incredibly useful, may be among our—shall we say, more regrettable inventions. They contribute to the 10 million tons of plastic that make their way into the oceans each year, polluting fragile ecosystems and killing wildlife. And for an item that’s only used once, it’s difficult to justify that kind of impact.
But nowadays, we continue to innovate new products and processes that can help us deal with the unintended negative consequences of plastics.
One such invention is bioplastic. But while certainly a better alternative to petroleum-based plastic, bioplastics aren’t perfect. Because of misleading marketing, there’s a lot of general confusion about what exactly are bioplastics, and what happens to them after you discard them.
Many consumers make the (often incorrect) assumption that bioplastics are always biodegradable. In some cases, bioplastics don’t break down any faster than regular plastic!
Biodegradable products are able to decompose in a matter of days, weeks, or months by microorganisms. These products don’t leave behind toxic residue as they break down, and they do so at a rate far faster than regular plastic (which may take hundreds of years to decompose).
Bioplastics are different from petroleum-based plastic because they’re made from “biomass”—organic material in various forms, often plant-based. Pulp that’s leftover from processing other products, like sugarcane, is a common source.
But the term “bioplastic” only refers to what it’s made from, not how it will break down after it’s thrown away. Some bioplastics, even though they’re made from organic material, have a molecular structure that isn’t easily broken down by microorganisms, so they’re not considered biodegradable.
Even biodegradable bioplastics are difficult to dispose of properly.
Some kinds of bioplastics, called bio-polymers, do biodegrade, but only under very specific conditions—and not the type of conditions created by your backyard compost bin. As a result, they must be composted in high-temperature industrial facilities, which aren’t available everywhere.
If the right facility can’t be accessed, the bioplastics are either going to the landfill—where there won’t be the conditions necessary to break them down any faster than regular plastic—or to a recycling facility, where they may contaminate entire batches of recyclable plastics. Most recycling facilities don’t have the technology to tell bioplastics apart from regular plastic, so in many cases bioplastics will get sorted out with non-recyclable plastics, and sent to a landfill.
Growing crops for bioplastics takes up space and resources that could be used to grow food or create habitat for wildlife, and requires the use of more chemicals.
The organic material needed to create bioplastics needs to be grown, just like any other crop. This means valuable land that could be used to grow food, or left to exist in its natural state, must instead be used for growing plants to be turned into bioplastic.
Growing crops for bioplastic also means fertilizers and pesticides are being used, and chemicals are needed to process the organic material into bioplastic. These steps all contribute to ozone depletion.
What’s the good news?
There’s still plenty of promise surrounding the concept of bioplastics as an alternative to regular plastic. Researchers are working on ways to turn feedstock into bioplastic, to avoid having to use food crops. These alternative materials include wood, corn cobs, straw, and potato waste. Others are looking into the use of algae, methane, and even milk proteins.
While there’s still work to be done to improve the effectiveness of bioplastics, there are many non-plastic biodegradable alternatives to common single-use plastic items. Look for eco-friendly products that are compostable, biodegradable, and plastic-free!