Plastic can be a problem. It might seem strange for a company called “Plastic Place” to acknowledge such a thing, but it is absolutely true. While the invention of plastic has done a massive amount for humanity, revolutionizing everything from sanitation to health care, no technological advance comes without its price. Improperly discarded plastic is one of the most urgent problems facing the environment today. According to the U.S. Environmental Agency, only 8% of the 31 million tons of plastic waste produced each year is recycled. Much of the rest ends up as litter and pollution, clogging waterways, threatening wildlife, and releasing potentially toxic chemicals into the earth. Being so aware of this conflict is what drives our commitment to finding greener ways of dealing with trash, especially when it comes to the production and disposal of plastic bags.
When biodegradable plastics first arrived on the scene, they were hailed as the scientific breakthrough that would cure all the problems that plastic can create. The idea of a plastic that would behave and break down just like a natural material seemed too good to be true. Was it? We took a look at the facts and found out.
What does “biodegradable” actually mean?
First it will help to define the sometimes confusing terms which are often used interchangeably when discussing biodegradable plastics.
“Regular” plastic is a synthetic material created from petrochemicals. Without getting too deep into the science, the long polymer chains in regular plastic are so resilient and resistant to breakdown that they can last for hundreds of years.
Biodegradable plastic, which is also made from petrochemicals, is manufactured differently so that it can begin to break down quickly in the presence of air and sunshine. You might see this plastic labeled as photodegradable or oxydegradable.
Bioplastic is made from organic, renewable sources, such as vegetable oils, corn, and grains.
Compostable plastic, which is usually bioplastic, doesn’t just break down: as it decomposes, it will create humus, which adds valuable nutrients to the soil.
One of the first problems with “biodegradable plastic” was that in the early days there was no consensus on what qualified as biodegradable. Dubious claims abounded as companies rushed to get on the green bandwagon and made all kind of promises to consumers that were not actually true. Eventually, the Federal Trade Commission stepped in with a strict set of guidelines defining exactly what could and could not be labeled as biodegradable. For a full explanation, you can take a look at the “Truth in Advertising” section of the FTC Green Guides here, but in short:
“The current Guides state that a marketer should qualify a degradable claim unless it can substantiate that the “entire product or package will completely breakdown and return to nature within a reasonably short period of time after customary disposal.”
Sounds good, right? Not so fast.
The limitations of biodegradable plastic
“Returning to nature” is a pretty poetic idea, but is that actually what happens when biodegradable plastic bags arrive at the landfill? The problem with the FTC guidelines is that some extremely important factors are completely left out.
First of all, the “reasonably short period of time” is not defined. It could mean any amount of time from a week to several years.
Next, and most importantly, there’s no discussion of the type of environment required for this breakdown to occur. The fact is that most plastic ends up in landfills. Canada’s Environment and Plastics Industry Council (EPIC) estimates that even though two thirds of the plastic in a landfill could be called biodegradable, once it reaches that dry and airtight environment, it pretty much halts the biodegradation process, and the plastic just sits there along with its non-biodegradable counterparts. By design, the conditions in a landfill are extremely hostile to the biodegrading process. Nothing is actually meant to decompose there: air, moisture, and sunlight, the three factors most necessary to decomposition, are purposely kept out of landfills in order to cut down on greenhouse gas emissions. This means that even if biodegradable plastic did break down in this environment, the consequences would be far from rosy. As it degrades, it releases two greenhouse gasses: methane and carbon dioxide, which both contribute hugely to global warming. Many traditional petrochemical-based biodegradable plastics also leave behind toxic metals and traces which can contribute to soil and water pollution.
As if that wasn’t enough, consider this: biodegradable plastic cannot be recycled with other plastics.
Biodegradable plastic is marked “7” while most other recyclable plastics are a “1” or a “2”. If bioplastic is mixed in with these, it will contaminate the whole batch. You don’t need to be an environmental scientist to know that’s not a good outcome.
Finally, even relatively friendly bioplastics have their drawbacks: arguably, the land and resources and carbon output used to grow corn and other materials for bioplastic might be better used growing actual food. The genetically modified crops used for the production of bioplastic and the necessary chemical fertilizer and pesticides have their own consequences for the environment. On a very practical level, these bags are often not as strong as the petrochemical-based bags, which means that they may require double-bagging. Using more plastic instead of less isn’t a sustainable solution.
What biodegradable plastics can actually do for the earth
Now we get to the good news. In spite of all the drawbacks, there are several ways that bioplastics can make a positive impact on the planet.
First, and this is huge, anything that cuts down on the amount of petrochemicals we consume is important. Fossil fuels won’t last forever, and the environmental, economic, and political implications of our dependence on foreign oil or ever more invasive methods of extracting domestic oil can be grave.
Many bioplastics made from materials such as cornstarch also require much less energy and carbon output to manufacture, and when they do break down under the right circumstances, they may give out up to 70% less greenhouse gas.
Truly compostable bags can also make a big difference. If your city offers a commercial composting facility, using these bags for your food and yard waste is a great option which may encourage more composting: a pure win for the environment. For do-it-yourselfers with a backyard compost bin, some bags are also suitable for home-composting, but check the label carefully.
Why behavior is more important than biodegradable bags
Whether or not you choose to use biodegradable plastic or bioplastics, at the end of the day, making good environmental decisions often comes back to what we do, rather than what we buy. The three Rs we learned in school on Earth Day are still the most important ways we can protect the health of our planet. Reducing the amount of plastic we use and throw away whether biodegradable or otherwise, is the most impactful choice we can make. Choosing long-lasting products instead of disposable ones and composting wherever possible helps keep plastic of all kinds out of landfills. Proper recycling has a multiplying effect: you throw less away and you need less plastic bags to contain your trash. For an extra measure of eco-friendliness, you can also choose recycled plastic trash bags, which reuse plastic that’s already here. As science and technology continue to progress, the question of whether biodegradable plastic is a net win for the environment will hopefully become more clear. For now, staying educated and thoughtful about our choices is the first step.