Q: From a scientific point of view, which is more environmentally sound: wooden chopsticks or plastic spoons? To be more specific, putting aside one's cultural preference, which method of putting food in the mouth causes least harm to the sustainability of planet Earth? (Yes, I know eating with hands is the best!)
Asked by Mike Fong Zhu, ’98, Fair Oaks, Calif.
Well, yes, hands are certainly one option! Assuming you are eating in a situation where you don’t have access to typical reusable utensils, there is another great option for on-the-go meals: reusable travel utensils. Collapsible stainless steel chopsticks or cutlery come in nifty cases, and sell online for around $5. But they only work if you have them with you: I forgot to bring utensils on a camping trip one time, and ended up shaving two twigs to use as chopsticks. Reusable products are almost always the best option, but they also can be easy to forget. If you don’t want to receive stares while whittling your own chopsticks in the mall food court, you're left with the question: plastic or wood?
It’s easy to assume that wooden chopsticks would be the better choice: wood is natural, renewable and—at least in theory—biodegradable. But consider the scale, and those slim sticks of wood seem less benign. According to the Chinese finance ministry, China disposes of 45 billion pairs of chopsticks each year. That’s the equivalent of nearly 3 million medium-sized birch trees per year! This has become such a great concern that the Chinese government imposed a five-percent tax on each pair of chopsticks starting in 2006. Not only is the chopstick harvest threatening China’s forests, but cutting and transporting the wood to chopstick manufacturers is energy intensive. Disposable chopsticks, in other words, are not a sustainable choice.
Regular plastic cutlery is typically made from polystyrene, which is derived from petroleum. This is not a sustainable resource because of the limited supply of fossil fuels, and the energy used and greenhouse gasses produced during manufacturing. Reliable data for the number of plastic forks, knives and spoons discarded each year doesn’t seem to be available—“40 billion sets” seems to be tossed around a lot, but we couldn’t find a source. It’s sure to be substantial, though, and even though polystyrene (plastic recycling number “6”) is accepted by many recycling centers, only about 9 percent of the material used for disposable plates, cups and other tableware was actually recycled in 2009 according to the U.S. EPA. That’s partly because polystyrene isn’t accepted everywhere, but it’s largely because people just toss it in the garbage. Reusables are the best answer, but if you must use disposables, don’t let an opportunity to recycle them pass you by. Disposable plastic, in other words, is another lousy choice.
What about biodegradable plastic cutlery? Bioplastics are typically made from cornstarch or vegetable oil. They are designed to break down on their own in less than 10 years. They also require less energy to produce than regular plastics. Bioplastic “compostable” cutlery has become ubiquitous on the Stanford campus, despite being more expensive than traditional plastic. But studies done by students at the Stanford Community Farm show that the bioplastic cutlery doesn’t actually decompose quickly in a typical compost pile. The material does better in large, commercial compost piles, which get hotter as they decompose than typical backyard compost piles do, though most commercial composters don’t leave piles for 5 or 6 months needed to fully decompose compostable cutlery. The use of food to produce plastics also brings up ethical questions of growing food to feed hungry people versus producing disposable items that will be used for 15 minutes. And that, unfortunately, is another unappetizing thought.
We here at SAGE pride ourselves on finding crisp, reliable answers to tough environmental questions. But short of launching a new master’s degree project, the relative impact of disposable plastic vs. disposable wood seems to be an unsettled issue. What is clear is that anything reusable (including your hands!) will be better than disposable cutlery.
Kathleen Low is a master’s student in environmental engineering and science.
