Compostable Plastics: Green Solution or Misleading Myth?

The term “compostable” is often confused with “biodegradable,” but they are not synonymous. While biodegradable plastics will eventually break down naturally, compostable plastics need specific conditions that are rarely present in landfills or natural environments. This means that, if compostable plastics end up in landfills, they contribute to long-term pollution just like traditional plastics. They may eventually degrade, but only under aerobic conditions with plenty of oxygen—a scenario unlikely to occur in the compact, oxygen-poor environment of a landfill.

Moreover, compostable plastics in landfills can create methane, a potent greenhouse gas, as they decompose anaerobically (without oxygen). According to secondary research, in 2019, compostable bowls used by restaurants like Sweetgreen and Chipotle made headlines for containing per- and polyfluoroalkyl substances (PFAS), chemicals linked to cancer and other health issues. If such compostable items are mishandled, they may introduce harmful substances into the environment, defeating the purpose of eco-friendly alternatives.

The Origins and Impact of Plastics

Plastic has been both a blessing and a curse. According to secondary research, since the 1950s, when chemists began transforming waste products from refineries into plastic, the world has produced more than 8 billion metric tons of it. Its versatility and durability have made plastic indispensable in various industries, from packaging and electronics to construction. However, these same qualities have turned plastic into a global environmental nightmare.

More than half of the plastic produced has ended up as waste, polluting land and sea. Plastics are responsible for more than 10,000 metric tons of waste flowing into oceans every day, and plastic’s resilience means that much of it will persist for centuries. Despite its profound impact on pollution, plastic has undeniably improved modern life in various ways, from increasing energy efficiency in homes to preserving food longer.

The Search for Sustainable Plastics

Researchers are now striving to create plastics that retain the beneficial properties of traditional plastics but with environmentally sustainable qualities. This includes developing polymers from biological sources that can decompose harmlessly. Traditional plastics are produced by breaking down refined petroleum into monomers, which are then reassembled into polymers. These polymers, mixed with additives, form the base of plastic products, but the process is highly reliant on fossil fuels.

Some alternatives, like bio-based plastics, are derived from renewable sources like sugarcane. Braskem’s bio-PE, for instance, captures carbon during its production, offering some sustainability advantages. However, it is still non-biodegradable, meaning it poses the same waste challenges as petroleum-based plastics.

Compostable plastics, such as polylactic acid (PLA), offer more promise. PLA can break down into harmless organic matter, but it requires industrial composting conditions, which are not yet widely accessible. Even when disposed of correctly, the infrastructure needed to handle compostable plastics is still lacking in many regions.

A Call for Innovation

The complexity of the plastic crisis demands innovation. Scientists are exploring more sustainable materials, including monomers derived from bio-sources. According to secondary research, in 2020, researchers in California developed a foam-like plastic from algae oils that could degrade effectively in soils. Other researchers suggest bypassing energy-intensive plastic production altogether and using natural polymers found in biology, like cellulose, which is abundant in plant cell walls. These materials break down more easily and at different timescales, making them more adaptable for various applications.

Looking ahead, corporations are also stepping up to the challenge. Colgate-Palmolive, for example, has committed to reducing new plastic use and achieving 100% recyclable, reusable, or compostable packaging by 2025. However, success requires more than corporate commitments; it will take widespread collaboration, clear regulations, and measurable goals to reduce the carbon footprint and make truly sustainable plastics a reality.

Last Word

Compostable plastics present a well-intentioned but complex solution to the plastic crisis. While they offer some benefits in controlled environments, the reality is that current infrastructure and public understanding are not equipped to handle them effectively. Compostable plastics alone cannot solve our plastic pollution problem. A combination of innovation, improved waste management systems, and clearer definitions around sustainability is needed to create lasting change.

The search for a truly sustainable plastic alternative is ongoing, and while progress is being made, the journey is far from over. The future of plastic may lie not in abandoning the material altogether but in finding ways to use it more responsibly and creating materials that can be returned to the environment without harm. Until then, we must be cautious of greenwashing and strive for genuine solutions that protect our planet for generations to come.