What's the Difference Between Biodegradable, Compostable, and Recyclable?
Understand these processes in order to best dispose of your trash.
Many of us are more concerned than ever about what we leave behind, and rightly so: Ramani Narayan, a Michigan State University professor of engineering with expertise in sustainability, says that 50 percent of the materials that go to landfill is organic waste. Organic waste is eventually converted to methane, which has over 28 times as large of an impact on global warming as CO2. And then there's the abundance of plastic. Plastics leach chemicals into the earth, water, and food.
It doesn't have to be this way. Most, if not all, of these products can be organically, mechanically, and chemically recycled. In order to make that happen, we need to do more than understand how these processes work and properly dispose of our trash; we also need to require our government to create better regulation and ensure that companies change the way they package or develop their products.
Recycling—or, more specifically, mechanical recycling—is the process of breaking down waste into small pieces in order to convert it into new products. Chemical recycling is less prevalent but possibly a better alternative to mechanical recycling as it actually breaks the materials down to their original molecules. The broken-down materials will then be sold off to other manufacturers for reuse. Both require the consumer to pay careful attention to cleaning off any food or other substances before properly sorting them into the right bins.
Some recyclable products, Narayan explains, are more effectively recycled than others. Milk jugs, water bottles, and the packaging of some personal hygiene products, for example, are made of polyethylene terephthalate (PET). This strong but lightweight plastic is completely recyclable, which means that PET can be totally broken down and reused to make more PET products. Unfortunately, recycled PET (rPET) is more expensive than buying the original material from petroleum refineries so manufacturers don't utilize it as much as they should. Because there is very little incentive for companies to make the switch, Narayan says that the need has to come from the consumer. "The more informed consumer has multiple ways in which to put pressure on politicians and brands to make change," he says. Narayan points to the fact that, in response to growing public concern about waste, companies such as Dasani, Levi Strauss & Co., and SC Johnson have made commitments to using more recycled materials to package their products, and have even incorporated recycled materials into the products themselves.
If a product is biodegradable, it means that it can break down safely into a natural form such as carbon dioxide or water without leaving behind any nasty chemicals. The systems an item is disposed into plays a big part in how an item breaks down. However, the term is so frequently misused—and sometimes even used in a way that is intentionally misleading—that Narayan says it doesn't carry much weight at all. "California actually prohibits the use of the word biodegradable in marketing," he explains. Without stating which biological system it is intended for, how long it will take to degrade, and whether or not it will degrade completely, saying that something is biodegradable is meaningless.
Like biodegradable products, if something is compostable it can degrade into a natural form in the right environment. The best part: compostable materials create a nutrient-rich byproduct that's great for soil. "Composting is the use of biodegradability to transform biological waste into a soil amendment product," says Narayan. This product replenishes the carbon in the soil, discourages weeds from growing, and makes the soil more porous.
Home composting systems can dispose of most household waste—from coffee filters and nut shells to cardboard and wool rags—if it is handled properly. Compostable paper and plastics, however, are much more difficult to process correctly. Ramani suggests only composting food waste at first because compostable packaging is best left to industrial composting plants. Still, it's important to note that something is only compostable if it is composted; like food waste, if "compostable" packaging goes to a landfill, it won't have the opportunity to degrade. It's just trash. Additionally, compostable packaging still faces controversy and isn't necessarily a sure bet, so whenever possible, it's always best to opt for reusable products or to upcycle the products yourself.