• Jessica Evans

Why is plastic bad?

Plastic is bad. Ever since we (young millennials) reached about grade 2 we’ve had the phrase “reduce, reuse, recycle” beaten into our brains. It’s kinda paid off - there’s a global movement for plastic reduction.

But who knows why plastic is so evil? We just know it is. But why? Isn’t it made of old, decayed organic matter?

Plastic doesn’t biodegrade. That means that, unlike all other organic material (stuff made out of living things or things that once lived), it doesn’t get broken down and it doesn’t return to the earth – at least not for a l o n g time.

Loads of restaurants and shops collect bottle tops or the plastic tabs that close plastic bread bags. Keep your eyes open for collection points near you. The proceeds of these small donations often go towards charities for people with disabilities.

The question of plastic’s biodegradability can be quite confusing. After all, it’s made out of organic matter and it can break down into microplastics. So how isn’t it biodegradable?

When plastic breaks down into microplastic particles, it essentially just becomes a smaller piece of plastic. It doesn’t change its chemical properties when it breaks down, so it can’t be reabsorbed into the cycle of life. Neither bacteria nor fungi nor animals can digest plastic, so basically it just stays plastic forever.

This is all because of its chemistry.

Most plastics are made of petroleum (ancient, decayed organic matter). Petroleum consists mostly of fats known as lipids. During processing for some kinds of plastic, a component of petrol called propylene is linked together making long chains called polypropylene – sound familiar?

This is the chemical structure of polypropylene. The C's represent carbon atoms and the H's represent hydrogen atoms. Polypropylene exists as long chains of this repeating pattern.

The problem with polypropylene is that there are no ways to digest it. The microorganisms that normally break stuff down can’t do anything with it because it doesn’t exist in nature and they’ve evolved to recycle what occurs in nature.

It all comes down to the bonds holding the molecule together. Organisms can’t break down plastics made with carbon-to-carbon bonds because it requires too much energy. But they can break down peptide bonds (a specific form of bonding).

The problem is, if plastic were made using peptide bonds, it wouldn’t keep very well and it would compromise the qualities that make it ideal for packaging, clothing and the like.

Reducing your plastic waste starts with cutting out as much unnecessary plastic as you can, but the chances are you have some plastic lying around, so why not put it to good use? Here are 5 ways you can upcycle a plastic bottle.

Aside from the fact that it doesn't biodegrade, plastic has the ability to attract toxins. Essentially, any chemicals that end up in the ocean with microplastics tend to stick to them. This makes the danger of microplastics even greater for sea life because if they consume them, they also consume all the toxins that stick to them.

Plastic recycling is monumentally important in reducing our impact on the environment. Because nothing in nature can break it down, its our job to do our best to reduce how much plastic is produced.

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