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What are Compostable Plastics?

Compostable plastics refer to materials that can be broken down by fungi, bacteria or microbes. They are produced from renewable materials like corn, potato, tapioca starches, cellulose, soy protein, and lactic acid.

Compostable plastics are commonly used for disposable items, such as packaging, cutlery, and takeout containers. Compostable plastics could in theory replace many applications for normal plastics, but there are several factors that make them problematic in real-life settings.

While making purchase decisions, consumers must beware of “greenwashing” (when a company provides misleading information about how their products are more environmentally sound than they actually are).

Issues With “Compostable” Plastics

1. Biodegradable and compostable plastics don’t mix with recyclable plastics

When compostable plastics are recycled into a blue bin, they can contaminate and degrade regular recyclable items. Since it’s difficult to separate traditional recyclable plastics from biodegradable plastics (they look almost identical), they are often missed. This can create an extra step for the recycling plant to sort and it can contaminate the other recycled products in the process.

2. Compostable plastic will not biodegrade in a landfill

Many compostable plastics are designed to decompose in an industrial composting system, however, this rarely happens to them. Many compostable plastics are usually discarded in our waste bin (which means they end up in a landfill) and cannot properly compost because these special plastics need air, moisture, and sunlight to break down properly. In a landfill setting, it can take decades or even centuries for the items to fully break down.

3. Some compostable plastics can still contain harmful chemicals

Not all compostable plastics are free of harmful chemicals like lead, cadmium, BPA and phthalates. Unless further tested, or properly stated on the packaging - it’s hard to know what exactly is in your compostable plastic product. These chemicals can cause cancer, or accumulate in our environment over time.

So essentially, unless a compostable plastic item ends up in a perfect laboratory composting setting, it can cause more harm to our environment than good.

What’s the solution?

Plastics play an important part in our world and will continue to in various applications. Where you cannot find truly compostable plastic, ensure that the plastic you are using is both recycled and recyclable so you are diverting plastic from landfills and not creating virgin plastic. A great example of this is RPET plastic. RPET plastics (recycled PET) are made from recycled plastic and are also recyclable. This type of plastic would have otherwise gone to landfill and can be recycled over and over again.

Avoid PET plastics, which are recyclable under certain conditions, but are not created from recycled plastic. PET plastic is made from virgin plastic, which means their production is adding more plastic to a world already overflowing with it.

You can also use products that are made of natural, and sustainable materials (like birch or bamboo). These materials are fully compostable and biodegradable and can break down fully, without leaving a toxic residue. These eco-friendly products are also visually different from plastic, or compostable plastic so can be properly sorted at waste facilities, if not composted properly.

Greenlid’s products are made from sustainably sourced Bamboo, Plant fibre, Wheat, Birch, and Palm Leaf - meaning they are fully compostable, biodegradable, and free from any harmful chemicals. They are the truly sustainable choice for your single-use dining needs.

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