The Myth of Sustainable Materials: Biodegradability and Microplastics

The retail market has seen a boom in environmentally conscious materials: post-consumer plastic, biodegradable packaging, and compostable coffee cups galore. For many consumers, these green alternatives are a huge selling point––it definitely is for me. Any product that claims to be eco-conscious gets an automatic check in my book. However, behind these labels lies a myth of sustainability. The most deceiving of them: biodegradability.

Biodegradability is simply defined as being capable of decomposing by bacteria or other living organisms. Most biodegradable plastics are bioplastics, made from plants and microorganisms rather than fossil fuels. Most consumers are under the impression that biodegradable plastics are preferred to say recyclable products, because of its “plant-based” nature. Additionally, many believe the story of biodegradable plastics ends by disposing of them in the garage. However, landfills lack the necessary microorganisms and oxygen to decompose these bioplastics in a timely manner. Most biodegradable plastics require industrial composters to properly break down, yet very few make it to one.

A research study from North Carolina State University shows that products labeled as biodegradable are doing more harm than good in landfills by releasing a powerful greenhouse gas as they decompose. The Federal Trade Commission guidelines ask for products labeled as biodegradable to decompose within "a reasonably short period of time" after disposal, whatever that means. Regardless, such rapid degradation may actually leave the environment worse off, because current regulations don’t require methane-collecting landfills to install gas collection systems for at least two years after the waste is buried. Meaning that much of the methane will end up being emitted before the collection technology gets installed. This faulty system results in less potential fuel for energy use, and more greenhouse gas emissions in our air.

Another valuable study was conducted by Imogen Napper at the University of Plymouth. Napper collected biodegradable and compostable carrier bags and put them in three different natural environments over the course of three years: buried in soil, left in the sea, and hung up in the open air. The study tested bags labeled as biodegradable and compostable.

In Napper’s experiment, the bag labeled compostable disappeared entirely within three months in seawater. In soil, it remained intact for two years, but disintegrated when loaded with shopping materials. The rest of the bags––including the one labeled biodegradable––were still unscathed in both soil and seawater after three years, and could even hold objects. After nine months exposed to air, all of the bags had either disintegrated or, troublingly, began to break down into microplastics.

And so, comes the plague of microplastics. “[A bag coming apart] doesn't actually mean it's breaking down into its most natural counterparts of carbon and hydrogen, it just means they're becoming smaller pieces… Which you could argue is more problematic because you can't clean up––it's like trying to pick up Smarties with chopsticks,” Napper stated.

These microscopic particles begin as waste products that are broken down by our oceans and sunlight and then pass through water filtration systems and wildlife habitats. Studies have found that “microplastics disrupt reproductive systems, stunt growth, diminish appetite, cause tissue inflammation and liver damage, and alter feeding behavior in fish and other marine and freshwater wildlife” (National Geographic). As of yet, microplastics (which have been detected in drinking water, salt, and other foods) have not been found to demonstrate harm to human health. Though, their negative lasting effects are far from small. Because they do not break down into their natural components, the fragments just become smaller and smaller, lasting for centuries. For these extensive aforementioned reasons, one-hundred percent compostable materials are chief among all disposal methods.

While being a well-informed consumer holds inherent value, the scale for improvement on producers’ ends is tenfold. The industry needs to demystify the process. In her study, Napper found that neither term (biodegradable and compostable) imply anything about the material’s ability to break down quickly in a natural environment. These ambiguities fall down on the shoulders of the federal government and consumer-facing companies.

We could start by creating a clearer labeling system, resembling that to the way recyclable products are marked on food packaging. Until we do that, compostables will end up incinerated, and plastics will end up in composting plants.

In this global problem lies innovative solutions. Look at Italy, where single-use bags for produce and baked goods must be compostable and can be recycled as part of widespread food waste collections. Italy has proven that these solutions are indeed in reach, and all work interchangeably. If food waste is done properly, recycling becomes immensely easier. We just have to begin perfecting this complex puzzle.

Again, removing the shackles of consumerism by being a smarter shopper holds serious weight. Though personally, I don’t necessarily believe it to be the consumer’s responsibility to skirt around an impossible market to be a socially responsible human. Consumers are rational actors seeking the most convenient choices laid out before them. Thus, it’s on the industry to make those choices simultaneously easy, affordable, and environmentally conscious.