Compostable vs. Biodegradable Bags: What's the Difference?

Disposable plastic bags have long been a topic of concern due to their impact on the environment. These bags, commonly used for grocery shopping or packaging, take hundreds of years to decompose, filling up landfills and posing a threat to wildlife and marine ecosystems. In an effort to address this issue, eco-friendly alternatives have emerged, including compostable and biodegradable bags. While both options aim to reduce the environmental impact of single-use plastics, they differ in terms of their composition and degradation process. This article will delve into the differences between compostable and biodegradable bags, shedding light on their strengths and limitations.

Compostable bags are designed to break down naturally into compost, a nutrient-rich soil amendment. Made from organic materials such as plant starches, cellulose, and cornstarch, these bags are specifically engineered to decompose in composting conditions. Composting requires specific conditions such as sufficient heat, moisture, and oxygen. The breakdown process results in the production of humus, a dark, organic material that improves the fertility and structure of soil. Compostable bags play a significant role in diverting organic waste from landfills, promoting a circular economy by turning waste into a valuable resource.

On the other hand, biodegradable bags break down naturally over time, but not necessarily into compost. They are typically made from petroleum-based plastics with additives that enhance their degradation process when exposed to certain environmental conditions, such as sunlight, heat, and moisture. Biodegradation refers to the breakdown of materials by microorganisms, such as bacteria or fungi, into smaller fragments. However, it is essential to note that the term "biodegradable" is not well-regulated and can be misleading. Some biodegradable bags may only break down into microplastics, tiny plastic particles that persist in the environment and can have detrimental effects on wildlife and ecosystems.

When it comes to choosing between compostable and biodegradable bags, it is crucial to consider the intended use and disposal method. Compostable bags are best suited for composting facilities, where they can break down quickly and contribute to the production of nutrient-rich compost. These bags are not suitable for regular recycling or landfill disposal since they require specific composting conditions to degrade properly. Compostable bags should be certified under recognized standards, such as the ASTM D6400 or EN 13432, to ensure their compostability and environmental safety.

On the other hand, biodegradable bags, especially those without proper certifications, should be used with caution. While they may break down over time, they can still leave behind microplastic fragments that can pollute the environment. It is important to be aware that biodegradable bags can take several years to break down, depending on the environmental conditions. Therefore, disposing of them in landfills or recycling programs that are not equipped to handle them appropriately may not be the most environmentally friendly option.

It is worth noting that both compostable and biodegradable bags have their limitations. Compostable bags require specific composting conditions and may not break down in home compost bins or regular landfill environments. Biodegradable bags, on the other hand, may not fully degrade into harmless substances and can still contribute to plastic pollution. Moreover, both options have a higher production cost compared to traditional plastic bags, which can affect their accessibility and wider adoption.

In conclusion, the choice between compostable and biodegradable bags depends on the intended use and the disposal method. Compostable bags are best suited for composting facilities, where they can break down naturally into nutrient-rich soil amendment. Biodegradable bags should be used with caution, as the term is not well-regulated, and they may still contribute to plastic pollution if not properly disposed of. Ultimately, reducing the use of single-use plastics, reusing bags, and promoting sustainable alternatives, such as reusable bags, are fundamental in tackling the plastic waste crisis and preserving our environment.