Styrofoam, an expanded polystyrene foam, is widely used for disposable items like plates due to its lightweight nature, insulating properties, and affordability. After use, these plates enter the waste stream, raising questions about their environmental fate.
The Enduring Nature of Styrofoam
Styrofoam plates do not biodegrade like organic materials. Instead, this plastic primarily breaks down into progressively smaller fragments over extended periods, eventually becoming microplastics. Styrofoam can persist in the environment for hundreds, if not thousands, of years. When buried in landfills, shielded from environmental factors, it can remain intact even longer, potentially indefinitely.
The Science of Polystyrene’s Persistence
Styrofoam is made from polystyrene, a synthetic polymer with long, stable carbon chains derived from fossil fuels. Its strong carbon-carbon and carbon-hydrogen bonds make it highly resistant to natural breakdown. Microorganisms lack the specific enzymes to cleave these polymer chains, preventing true biodegradation.
While resistant to most chemical degradation, ultraviolet (UV) radiation from sunlight causes photodegradation. This process makes polystyrene brittle and causes it to crumble. However, photodegradation only breaks the material into microplastics; it does not convert it into organic matter or eliminate it from the environment. Polystyrene’s inherent stability also means it repels water and resists acids, bases, and salts, contributing to its long lifespan.
Environmental Implications of Slow Degradation
The prolonged persistence of Styrofoam leads to significant issues, particularly microplastic accumulation. As plates fragment, they release these particles into soil, water, and air. Once in the environment, microplastics readily enter the food chain, impacting a wide range of organisms.
Wildlife can ingest them, either mistaking them for food or through food chain transfer. Ingesting plastic can cause physical damage, such as blocking digestive tracts, or lead to a false sense of fullness, resulting in starvation. These fragments create a persistent environmental burden, accumulating in landfills and natural ecosystems.
Towards Sustainable Alternatives and Practices
Addressing the environmental impact of Styrofoam plates involves adopting more sustainable practices. Reducing their use is a primary strategy, often by choosing reusable alternatives like ceramic or durable plastic dinnerware. When disposables are necessary, options that break down more readily are available.
Compostable plates made from materials such as paper, sugarcane fiber (bagasse), bamboo, or cornstarch-derived polylactic acid (PLA) offer more environmentally friendly choices. These alternatives are designed to biodegrade or compost under appropriate conditions. While Styrofoam is technically recyclable, consumer recycling programs are limited due to challenges in collection and processing. Therefore, prioritizing reduction, reuse, and the selection of truly compostable or biodegradable alternatives remains an effective approach to mitigating its environmental burden.