Many of us are aware there is considerable controversy about the growing use of bioplastics in this country and around the world. Bioplastics, just so we are all on the same page, are made by extracting sugar from plants such as corn and sugarcane and converting it into one of two different types of plastic.
- PLA: polylactic acids, often used for food packaging
- PHA: polyhydroxyalkanoates, found in some medical devices and used to make cardiovascular patches
Among the benefits touted for the use of bioplastic is that it can help us reduce the use of petroleum. Further, because it is derived from renewable resources and the plants can be grown all over the world, this can help improve the economies of many poorer countries along with the pocketbooks of smaller, rural farmers.
Additionally, supporters for the use of bioplastic say that once it is discarded, it releases fewer carbons into the atmosphere compared to petroleum-based plastics. This hypothesis is based primarily on the belief that as the bioplastic degrades, it merely returns an amount of carbon into the atmosphere comparable to what was initially absorbed by the corn and sugarcane plants in the growing process. In other words, it is essentially carbon neutral.
However, arguments are surfacing that using corn and sugarcane for bioplastics reduces agricultural resources that could be used to grow food. Further, a 2010 study at the University of Pittsburg concluded that along with diverting land for food production, the fertilizers and other products used to grow corn and sugarcane for bioplastics create a considerable amount of pollution.
According to the report, while bioplastics can help reduce “fossil fuel use and global warming potential, [it] increases in other impact categories such as eutrophication (a process that removes oxygen from waterways, negatively impacting plant and marine life), human health impacts, and eco-toxicity. These impacts result from fertilizer use, pesticide use, and land use change required for agricultural production as well as from the fermentation and other chemical processing steps.”
But what happens once bioplastics are discarded is one of our primary concerns about the growing use of this product. Typically, bioplastics are either sent to landfills or delivered to industrial recycling facilities, where intense heat is used to break down the bioplastic and allow it to be recycled, just like traditional petroleum-based plastics.
But, if the bioplastic is simply delivered to landfills, just like traditional plastics, it can take decades to break down. During that time, should it leak from the landfill into oceans or waterways, it will not biodegrade and can harm plants and marine life.
Further, delivering bioplastics to industrial recycling facilities may not be the answer. For one thing, there are only approximately 150 such composting facilities in the United States. Of this small number of facilities, roughly 75 percent accept yard and more traditional waste items, but only about a fourth accept bioplastic waste. While there is no comprehensive data available, it is believed that many of these industrial recycling facilities that do accept bioplastic waste do not provide the intense heat necessary for a long enough time to break down the plastic for recycling purposes.
We should also add one more point. Even if a community has an industrial recycling facility capable of adequately processing bioplastics, the items may never get there. This was uncovered in a study conducted by Lonely Whales, a non-profit that helps businesses minimize their environmental impacts. According to their study, even in facilities that have compost or recycling bins, bioplastic items such as eating utensils are often not tossed in the appropriate recycling bins. As a result, the waste ends up in landfills, not the recycling facility.
“We quickly realized that the idea of compostable plastic sounds very interesting, but there’s still that human element of you and me,” said a spokesperson from Lonely Whales. The study also concluded that without a composting infrastructure, consumer buy-in and practice, the use of bioplastics could end up being a new type of greenwashing. This, as most of us know, occurs when consumers believe the use of a certain product is good for the environment or helps promote sustainability when in reality, it does not.
So, if products made from bioplastic enter the ocean or are placed in landfills, and if composting either doesn’t work or is not available in most communities, then why are we encouraging the customer to use bioplastic products, especially when they often come at a cost premium? While well intended, this is clearly an issue that needs to be rethought.
Stephen P. Ashkin is president of The Ashkin Group, a consulting firm specializing in green cleaning and sustainability.