Can you Compost Biodegradable Plastic?
Biodegradable plastic has been touted as the solution to the problem of plastic pollution. Sounds great in theory, but the problem is that many “compostable” plastic bags, cup lids, and utensils do not break down during composting. On top of that they then contaminate recyclable plastic resulting in a real mess for recyclers. The truth is that most compostable plastics are made from polyester called polylactic acid (PLA) that ends up in landfills along with the plastics made in the 1950’s. So, the answer to the above questions is yes and no. Biodegradable plastic breaks down with the aid of microorganisms into water, carbon dioxide, and compost within weeks to months. Some of these bioplastics, however, are made from biomass that can’t be easily broken down and are then non-biodegradable.
How to Dispose of Compostable Cups
Compostable cups and other containers biodegrade at the same rate as other organic materials when composting and with no toxic residue. This does not mean though, that they are safe to add to your compost pile. Generally compostable plastic is meant to go to an industrial composting facility which has higher temperatures than that of a home compost bin. In lieu of adding to the compost pile, some restaurants and companies have a special bin for compostable products, separate from trash or recycling.
Are Biodegradable Bags Compostable?
So here’s the problem. Biodegradable and compostable are often used interchangeably when in fact they are very different. Biodegradable bags are made from petroleum that has been incorporated with heavy metals. Some types of bacteria will feed on the metals in the plastic and break it down more quickly than non-biodegradable plastic. Compostable bags are those made from naturally occurring materials that break down easily and are non-toxic. The use of the term compostable is regulated while that of biodegradable is not. So, no — biodegradable bags are not compostable. Under specific conditions they will break down over the course of a few months but not in a landfill. Conditions in a landfill are not conducive to the breakdown of biodegradable bags and they can in fact sit for decades to centuries.
