4. Biodegradable Plastics

Biodegradable plastics (a type of bioplastic) have been developed to attempt to mitigate the plastic waste management problem. Plastic once produced, doesn’t just disappear. It’s either sent to landfill, incinerated, recycled (only 9% of plastic has ever been recycled), or ends up polluting the environment.

Biodegradable plastics can be broken down by microorganisms into safe by-products such as water, natural gas and biomass. A big concern with biodegradable plastics is whether or not they actually degrade in practice. 

Biodegradables need certain conditions to decompose e.g. certain levels of moisture, heat and oxygen. Compostable plastics are a type of biodegradable plastic that need specific industrial conditions to decompose; you can’t just leave them in your compost bin. 

Conditions for biodegradability are often not met in the real world environment. Plastic that ends up on land and in oceans may not degrade for many years. If biodegradables do not properly degrade, or only partially degrade into microplastics, they may cause pollution and harm.

Most biodegradable plastics are not bio-based (and vice versa). In other words, they are still made from fossil fuels and face the same sustainability issues as traditional plastics. 

An unintended consequence of biodegradables is the confusion they may cause in waste collection. If they are accidentally mixed in with traditional plastic recyclables, lower grade recycled material may be produced. On the other hand, if biodegradables are collected with organic waste, some traditional plastics may be accidentally collected, leading to contamination. 

Consumers may believe they are helping the environment by purchasing biodegradable plastics (and in fact all types of bioplastics). This enthusiasm may inadvertently increase overall plastic demand and associated pollution.