Ask Our Help Desk: Are bioplastics and biodegradable plastics really better?

How do you know if the ‘green’ disposable plastic products you buy–marked bioplastic, biodegradable, compostable, or bioplastic–are actually safe for our planet and our health? It’s confusing for well-intentioned people. We’re here to help.

Plastic is made of artificially created chemicals “that don’t belong in our world and don’t mix well with nature.” After we use plastic–sometimes only for a few seconds–we throw it away. These plastics are a big source of pollution, getting into our food and water, creating toxic health hazards for neighboring communities as part of their production and disposal and killing marine wildlife. While public pressure has made companies appear to be more environmentally friendly, most haven’t cleaned up their act. They’ve only created more confusing terms, greenwashing their products to make us feel like we’re acting responsibly.

The bottom line: the best solution is to avoid single-use plastics, no matter what material they are made from. It’s the only real way to prevent pollution and waste. When plastic is unavoidable, it’s vital to understand what the labeling actually means. Biodegradable plastics are very rarely recyclable, and biodegradable does not mean compostable–so they often up in the landfill. Compostable and bioplastic goods can be a better choice than biodegradable ones, but often still end up in landfills unless you can compost appropriately.

Why? There’s an important difference between what makes conventional plastics, biodegradable plastics, and bioplastic–and what happens when we’re done using them.

Conventional plastics are made from products derived from petroleum. The US Department of Energy reports that plastics are mostly produced from from natural gas processing, and feedstocks derived from refining crude oil–these are the ingredients that last forever in our environment. They take hundreds of years to break down and never completely decompose–they just become smaller and smaller pieces that are impossible to remove from the environment. Some plastics are known to be toxic, and as they break down, plastic bits become food for organisms up and down the food chain.

Biodegradable plastics are made from the same materials as conventional petroleum based plastics, but with even more chemicals. These extra chemicals cause the plastic to break down more rapidly when exposed to air and light. Some biodegradable plastics fragment rather than biodegrade, due to the addition of oxidizing agents (found in “oxo-degradable plastics”). By fragmenting, rather than degrading, they break into small pieces which can pollute soils, increase risk of ingestion for animals and end up in our oceans and waterways. These kind of plastics are impossible to recover for recycling and aren’t suitable for composting. The prefix “bio” can be very misleading: plastics do degrade, but not into something biological. It breaks into smaller and smaller pieces of plastic.

Unfortunately, recycling your ‘biodegradable’ plastics isn’t a great answer to this issue. Most biodegradable plastics have a #7 recycling code on them, which places them in the ‘Other’ category of plastics. #7 plastics are generally not accepted for recycling by local municipal recyclers, due to the addition of chemical additives.

Bioplastics and ‘compostable’ plastics tend to be made from plant biomass, such as corn starch, sugar cane or wheat, and should either completely and rapidly break down biologically, or be compostable. This means they are supposed to break down into biological elements, unlike conventional plastics. However, while some bioplastics can be composted and do not harm the quality of compost, others leave toxic residues or plastic fragments behind, making them unsuitable if your compost is being used to grow food. Additionally, the use of plant material for bioplastics causes concern including the use of genetically modified crops, and the use of farmland that could be used to grow valuable food crops, deforestation, use of fresh water supplies, soil erosion, fertilizer use (which comes from petrochemical sources), food security and more.

Bioplastics cannot be recycled with standard plastics as the additives in bioplastics can make the recycled product less durable.

Composting bioplastics is also complicated. Most bioplastics will only compost in commercial (municipal) composters. Commercial composters reach temperatures and humidity levels you would be unable to achieve in a standard garden composter, so your bioplastics may never break down at home. Some commercial composters, like those in Northern California, have to remove bioplastics like compostable utensils because even their temperatures and humidity levels will not break down these products.

So, is sending these items to landfill the best way to dispose of them? In a landfill, they won’t contaminate recycling or compost streams. But for biodegradation to occur, three basic resources are required – heat, light and oxygen. In a landfill site, waste is entombed, creating a complete absence of light and oxygen. If a biodegradable plastic or bioplastic ends up in a landfill site it may never decompose.

It’s clear: we can’t recycle or compost our way out of the plastics issue – and that holds true for new biodegradable plastics and bioplastics. We can make informed decisions and stop waste by buying less, and buying responsibly! Come to our Store for dozens of affordable products and strategies for reducing your reliance on plastic.

Also: check out these Responsible Purchasing Guides for more detailed information on the products mentioned above.

Sources:
https://www.eia.gov/tools/faqs/faq.php?id=34&t=6
http://www.explainthatstuff.com/bioplastics.html
https://www.theguardian.com/environment/2016/may/23/biodegradable-plastic-false-solution-for-ocean-waste-problem
https://www.theguardian.com/environment/cif-green/2009/jun/18/greenwash-biodegradeable-plastic-bags

[Photo credit: U.S. Department of Agriculture on Flickr]


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