In our daily life, plastic bags are omnipresent. When we visit the local grocery market, we are handed plastic bags to carry our fresh produce. Similarly, for food delivery orders, meals often arrive wrapped in plastic bags. However, this extensive use has led to severe environmental problems. “White pollution” has become a common sight, with plastic bags littering streets, parks, and rural areas. Moreover, a staggering amount of plastic bags end up in the ocean, contributing to the ever-growing marine litter. These bags harm marine life, entangling animals and being ingested by them. Are Plastic Bags Biodegradable? As it directly impacts our efforts to combat this pollution and protect our environment.
Are Plastic Bags Really Bad for the Environment?
Yes, plastic bags are really bad for the environment. They are made from non-renewable resources like petroleum. In the soil, they persist for centuries, impeding water and nutrient flow, thus harming plant growth. When plastic bags enter water bodies, they break into microplastics, contaminating water and being ingested by aquatic organisms. Moreover, countless marine animals die each year after getting entangled in or consuming plastic bags. Their slow decomposition rate and widespread use make them a major contributor to environmental pollution.
Are Plastic Bags Biodegradable?
The majority of conventional plastic bags are crafted from polyethylene, a polymer derived from petroleum. This material features long-chain molecular structures that are incredibly stable. In natural settings, such as forests, beaches, or farmlands, these bags can endure for an astonishingly long time, often ranging from 200 to 1000 years.
Even when subjected to the elements like sunlight (ultraviolet rays), water, and oxygen, they don’t decompose completely. Instead, they fragment into smaller pieces, which are termed microplastics. These microplastics have seeped into every corner of the environment. They contaminate soil, disrupting its natural structure and nutrient-cycling processes. In water sources, from rivers to oceans, they are ingested by a wide variety of aquatic organisms, from tiny plankton to large fish, causing internal injuries and potential toxicity as they move up the food chain.
On the other hand, there are “biodegradable” plastic bags available. These can be classified into different types. Some are made from plant-based polymers like cornstarch, while others are modified petroleum-based polymers engineered to be broken down by microorganisms. For the plant-based ones, they are designed to be consumed by bacteria and fungi in the presence of moisture and oxygen.
Their degradation is far from guaranteed. High-temperature composting facilities, which maintain a temperature around 50 – 60°C, with proper moisture levels of around 50-60% and sufficient oxygen, are ideal for their decomposition. But in regular landfill environments, which are predominantly anaerobic (oxygen-deficient), the process is severely impeded. Moreover, certain biodegradable bags, even under optimal conditions, may leave behind chemical residues. For instance, some bags made with additives to enhance biodegradability might release substances that could be harmful to soil or water organisms.
In conclusion, traditional plastic bags are decidedly non – non-biodegradable. As for biodegradable plastic bags, their biodegradability is conditional, complex, and closely tied to specific disposal and environmental conditions.
How Long Does It Take for a Plastic Bag Can to Decompose?
The decomposition time of a plastic bag can vary significantly. Regular plastic bag cans, often made from polyethylene terephthalate (PET) or high-density polyethylene (HDPE), take an extremely long time. In a landfill or natural environment, they can persist for 400 to 1000 years. This is because their polymer structures are highly stable, resistant to the action of microorganisms and environmental factors like sunlight and water.
On the other hand, biodegradable plastic bag cans have a much shorter decomposition period. Made from materials such as plant-based polymers, they can break down within a few months to a couple of years under ideal conditions, which include proper temperature, moisture, and the presence of specific microorganisms. In less – than – ideal environments like anaerobic landfills, their degradation may still be significantly delayed.
Other Bag Alternatives and Their Considerations
Oxo-biodegradable Bags
Oxo – biodegradable bags degrade through a two – step process. Initially, when exposed to air and sunlight, oxidation breaks the long polymer chains in the plastic into shorter segments. Then, these shorter chains become more vulnerable to microbial attack, enabling biodegradation. However, they have significant limitations. In landfills, which lack sufficient oxygen and sunlight, their degradation process is severely impeded, often leaving large portions un-decomposed.
During the oxidation process, they can fragment into microplastics, which are a growing environmental concern. In terms of cost, oxo – biodegradable bags are generally more expensive to produce compared to regular plastic bags due to the added manufacturing steps for incorporating oxidation – promoting additives. When it comes to environmental impact, while they seem like an improvement over traditional plastics, their incomplete degradation and microplastic production still pose risks similar to non – biodegradable plastics.
Paper Bags
Paper bags are indeed biodegradable. Under suitable conditions, such as in a composting environment with proper moisture and oxygen, they can break down relatively quickly, usually within a few weeks to a few months. However, there are trade – offs. Their production involves significant deforestation as trees are cut down to make pulp for paper. Additionally, the manufacturing process is energy-intensive, resulting in a higher carbon footprint compared to plastic bag production.
In terms of durability, paper bags are generally less sturdy than plastic bags and may not be suitable for heavy or sharp-edged items. Their reusability also depends on their quality; thinner paper bags may only be used once or twice, while thicker, more reinforced ones can be reused a few more times, but still not as many times as some heavy-duty reusable plastic or fabric bags.
Conclusion
The plastic bag degradation issue is complex. Regular ones take ages to decompose, while biodegradable types have their own limitations. Given this, it’s urgent to cut down plastic bag use. Reusable eco-friendly bags are a great alternative. The government should set policies, enterprises can innovate and promote sustainable products, and individuals can change habits. By working together, we can develop environmental habits and build a more beautiful, plastic-free earth.