How to make more sustainable purchases: Exploring plastic, glass, and aluminum packaging

By Mythreyi Rajasingham

When it comes to purchasing pre-bottled drinks, our choice of packaging material can help keep the environment and its inhabitants healthy and safe from toxins. 

Although plastic, glass, and aluminium bottles/cans vary in the ways in which they impact the environment, a lack of proper communication has caused most consumers to falsely believe that glass bottles are more sustainable than plastic and aluminium ones. 

To find the most eco-friendly option, most sources have compared the sustainability of plastic, glass, and aluminium bottles/cans by looking at the three stages of their lifecycle: production, transportation, and recycling.

Plastic bottles

Recently, plastic has garnered significant attention due to its environmental repercussions, with one prevalent example being its  harmful impact on marine life, particularly turtles. However, due to its lightweight nature and affordability, plastic bottles, commonly made from polyethylene terephthalate (PET), have emerged as the favoured option among consumers. 

Although plastic bottles use less energy during production and transportation because of their light weight, they require the extraction of crude oil, a non-renewable resource (“Glass, aluminum, plastic,” 2021). The act of oil drilling also damages the environment by contributing to the emission of greenhouse gases, which has led to global warming and climate change. 

Compared to glass and aluminium bottles/cans, plastic bottles are significantly less recycled, reducing their overall sustainability (Murphy, 2020). With this in mind, plastic bottles, while favoured for their lightweight nature and affordability, pose serious environmental challenges due to their impact on marine life, reliance on non-renewable crude oil, and low recycling rates compared to glass and aluminium alternatives. 

Glass bottles 

Compared to plastic, the production and distribution of glass requires much more energy because this material is heavier and more fragile. And due to their fragility, glass bottles cannot be tightly packed during transportation, which leads to more frequent shipments and, consequently, consumes a greater amount of fuel. 

According to a recent study conducted in Italy, the majority of consumers perceive glass bottles as the most environmentally sustainable choice (Feo, 2022). This perception aligns with the fact that glass bottles can be recycled endlessly. 

But when considering factors like production and transportation, it is clear that glass has a greater number of disadvantages than benefits.

For instance, glass relies on a finite resource: sand. The UN Environmental Programme has declared sand as the “second most exploited natural resource after water” (Bero, 2022). As noted by Toronto-based journalist Nehal El-Hadi, sand is not only essential for glass production but also for constructing cities, which has contributed to its scarcity.

In addition to this, since the process of collecting and sorting glass bottles has its own challenges, glass can actually be difficult to recycle.

This clashes with the consumer belief that glass bottles are environmentally sustainable due to their ability to be recycled endlessly. In fact, life cycle assessments (LCAs), which look at the energy consumption, resource use, and waste production of various materials, have determined that glass is the least sustainable option. 

Aluminium cans 

In recent years, aluminium cans have gained popularity because of their light weight and ability to be repeatedly recycled without a loss in quality. Unlike glass bottles, aluminium cans can be tightly packed when shipped because of their size and weight, which saves a lot of fuel and emits less greenhouse gas into the atmosphere. 

But despite these positives, it is worth noting that aluminium production relies on the extraction of bauxite, a mineral that poses risks such as water contamination and soil erosion when mined (Murphy, 2020). 

Like glass and plastic, the sustainability of aluminium cans depends on factors such as recyclability and is influenced by production and transportation processes. As a result, it becomes challenging to label one type of bottle as more sustainable than others without considering each of their unique contexts. 

Yet, several studies have suggested that, in general, aluminium cans tend to be more sustainable compared to glass and plastic options. 

While aluminium cans offer advantages such as a lightweight design, efficient transportation, and high recyclability, their sustainability must be considered in light of factors like bauxite extraction and production processes. 

Plastic, glass, or aluminium?

In the end, choosing the most sustainable packaging material for pre-bottled drinks requires the consideration of various factors. 

While each option has its own advantages and drawbacks, it is important to focus on reducing overall consumption, promoting recycling, and supporting a circular economy. 

So, although most sources have labelled aluminium cans as the most sustainable choice and glass bottles as the least sustainable choice, it’s important to remember that all these options have negative impacts on the environment. 

With this in mind, if the intention is to decrease environmental consequences when choosing what type of bottle/can to buy, the more eco-friendly option would be to buy aluminium cans and recycle them afterwards.

However, the most sustainable choice is to reduce the consumption of pre-bottled drinks altogether and instead opt for reusable bottles

In any case, it is important to keep in mind that even though the fate of our planet may seem bleak, we all have the power to minimise packaging waste and, in the process, lead our planet towards a more sustainable future.

​