A Plastic Solution

by Fiona Cheng and Sara Francis

Even though it’s harmful to the environment, plastic has become a part of our daily lives. Plastic bottles and containers can be recycled, but this process doesn’t actually work as perfectly as you might think, and lots of plastic placed in our recycling bins ends up in landfills. A plastic bottle placed in a landfill takes about 450 years to decompose!

Could biodegradable plastics - plastics that can be broken down by microorganisms into biological material - be the solution to this problem?

Click the pic to to read our previous article about the discrepancies in plastic recycling. This link will redirect you to Issue 6.

Biodegradable plastics have been hailed as the saviour to our plastic problem. Under the correct conditions, biodegradable plastics take between 3 and 6 months to fully decompose. This is a lot better than the alternative of several hundreds of years. However, the process isn’t always so great. To produce biodegradable plastics, chemical additives or special enzymes are added in order to accelerate the decomposition of the plastic.

Unfortunately, many of these additives have various negative impacts on the environment. Some biodegradable plastics release harmful toxins like iron, cobalt, and manganese. Furthermore, the decomposition of many biodegradable plastics release microplastics. These extremely small pieces of plastic (less than five millimeters in diameter) come from a variety of sources, such as tire fragments and the washing of synthetic fibers (aka laundry!). Microplastics are washed into our waterways, where they are ingested by small fish. Their negative impacts, which include stunted growth, diminished reproduction rates, and a decrease of general health of many species, work their way along the food chain. This also impacts us humans, as we can ingest these plastics when we eat fish.

Microplastics

Additionally, biodegradable plastics need the right conditions to decompose. While there are many different types of biodegradable plastics that require different conditions, in general, the enzymes need heat, good airflow, and water to do their job and decompose the plastic. This means that your average landfill, where trash is just piled up, does not create ideal conditions for biodegradable plastics. And worst of all, without the right conditions, biodegradable plastic is basically just regular plastic, but with more chemicals!

A landfill

However, it’s not all bad. There is a new process for biodegradable plastics that uses a special enzyme to break down plastic into 100% organic compounds (no toxins!). This state-of-the-art process requires conditions that aren’t nearly as complicated, just a little bit of water and some heat (the process does still work without heat, it just slows the decomposition rate). This means that the process works well in municipal composting areas. Not only that, the enzymes are more evenly distributed throughout the plastic for faster/more even decomposition. All these things lead to a higher - though not perfect - percentage of decomposition success. The process is still certainly far from perfect, but it continues to improve!

In summary, while biodegradable plastics have the potential to work really well, it’s also important to remember to reduce your plastic consumption as much as possible. Consider looking for alternatives to plastic products and/or purchasing products with less packaging to reduce your environmental footprint. Although it may seem as though the actions of one won’t have a big impact, we can make a difference together!