Compostable or Recyclable? Why Bioplastics Are Causing an Environmental Headache
You’re standing in front of three bins – one for compost, one for recycling and one for landfill – holding an empty container called a “PlantBottle” and a clear plastic cup embossed with the recycling triangle and the number seven. Now what?
Your instinct might be to put that “PlantBottle” in the compost bin, and to put the clear plastic cup in the recycling bin. But in this case, you’d be wrong on both counts.
PlantBottle is Coca-Cola’s brand for its bio-based plastic bottles, and while they are made either partially or wholly from plant-derived materials, they have the identical chemical structure of plastic made from oil, and therefore should be recycled right along with petro-derived plastic. A PlantBottle, despite its name, can’t be composted.
And the cup bearing the recycling logo and the number seven? Seven is the catchall for plastics that aren’t generally recyclable but that a few curbside systems might take – things like durable goods such as sunglasses, DVDs and some types of rugged plastic packaging. Compostable plastic is lumped under number seven, too. This cup in your hand happens to be a compostable bioplastic material, PLA, and so, though it might seem counterintuitive, it is supposed to go in the compost bin. Of course, if the word “compostable” were printed on the cup, this would be obvious. But such hints are not always provided.
If this all seems confusing, that’s because it is. But we’re here to shine a light on bioplastic packaging and its end-of-life story, because you’ll be seeing more and more of it in the coming years. Any sustainable business worth its weight in wheatgrass is starting to use bioplastic packaging. And within the packaging industry, this stuff is the new black. The market for bioplastics is forecast to grow at an average annual rate of about 25 percent through 2015, with production reaching 884,000 tons by 2020.
Set against the haunting images of our plastic-choked oceans and landscapes, and considering the pathetically low recycling rates in the US (only about 30 percent of polyethylene terephthalate, or PET, bottles are collected for recycling), the rise of bioplastics seems, at first glance, encouraging. With municipalities across the country banning standard, petroleum-based, single-use plastics and some mandating residential composting, more businesses and consumers are looking for plastic packaging that will, poof!, disappear once its short, useful life is over.
But – spoiler alert – that’s not actually how it all works.
For one thing, bioplastics vary widely in terms of both their base material and their ability (or inability) to biodegrade. For another, bioplastics are causing problems for both plastics recyclers and for commercial composting facilities because they are often wrongly sorted.
So while bioplastics have the potential to significantly reduce our dependence on fossil fuels to create packaging, they’re no panacea. And they don’t always work as advertized. In fact, they often overpromise and underdeliver, says Jack Macy, commercial zero waste coordinator for San Francisco’s Department of the Environment. When it comes to claims around bioplastics being biodegradable and compostable, “there’s about as much greenwashing and distortion of reality as anything I’ve seen,” he says.
First, let’s start with a primer on the term “bioplastic.” Basically, a bioplastic is a polymer made – wholly or in part – from a renewable, plant-based feedstock. There are some exceptions to this rule, such as Ecoflex, a bioplastic made from petrochemicals. It earns its “bioplastic” label from the fact that it will biodegrade when placed in a commercial composting system. As you can see, the term bioplastic is quite broad.