Are bioplastics the hero we’ve been looking for… or just another villain in disguise?

Bioplastics are taking over the event world and are being used as a substitute to their plastic serve ware competitors. But are they really any better? Bioplastics look, well, like traditional PET plastic, but are instead engineered from plant material rather than petroleum. You might have also heard of them as PLA, which refers to the Polylactic Acid used to create the bioplastic. The plant origins of the bioplastic comes from the process of fermenting materials such as cornstarch or sugarcane to produce lactic acid. The lactic acid goes through further processing and drying to create the solid product we know as bioplastic.  

Bioplastic’s claim to fame is that they are biodegradable and commercially compostable, something that traditional PET plastics can’t compete with. When it comes to the terms biodegradable versus compostable, all composting is always biodegradation, but not all biodegradation is composting. For bioplastics to be composted and turned into a usable product, they require high temperatures and specific microbes to break them down in a reasonable timeframe, which wouldn’t happen if you buried them in your vegetable garden at home. You would still see the item looking the same as it did when you buried it 6-months ago. In a wider environmental sense, that biodegradable item can still cause a lot of damage to our oceans and wildlife even though it won’t be around as long as traditional plastics. The difficulty in quickly distinguishing bioplastic from PET plastic also means that there is no council in New Zealand who will take bioplastics in their green waste programme, meaning that the commercially compostable claims, albeit true in some countries, are meaningless here.

If bioplastics can’t be commercially composted in New Zealand, what about recycling? If you look closely on the bottom of a bioplastic container you’ll see a recycling symbol on it with a number 7 in the middle. The true meaning of the recycling symbol itself has been greenwashed over the years into meaning the plastic is inherently recyclable, which was never the intention. The symbol, in fact, was designed to identify the type of plastic used to create it, as denoted by the number in the centre. So back to the number 7, what does that mean? Well, number 7 in the recycling world is the number for all of the misfits that don’t fall into the classifications for numbers 1 to 6, and in other words, it’s not recyclable.

So where does that leave us when it comes time to dispose of these single use “plastics”? Unfortunately we currently don’t have much choice but to send them to landfill. All of the time and energy that has gone into creating a sustainable product ultimately ends with it being disposed of in an even worse way than its plastic counterparts. Although bioplastics divert the virgin materials away from petroleum based sources, we in New Zealand do not currently have the infrastructure capable of handling the ongoing waste stream requiring disposal. From 1 July 2023 the New Zealand government committed to phasing out the use of additional single use plastics including plastic plates, bowls, straws, and cutlery. As we make these changes, my only hope is that we don’t work so hard to imitate a plastic product that we miss the opportunity to ask ourselves whether we really needed it in the first place? The phasing out of single use plastics should also be an opportunity to reassess the societal habits we’ve created for ourselves and adjust our attitudes towards waste.

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