Glass bottles are much worse for the environment than plastic ones, study finds

Glass bottles are more than four times as damaging to the planet as plastic ones because they require far more energy and natural resources to produce, according to a study.

© Provided by The i Around 20 per cent of the raw materials used to make glass are lost as CO2 and other gases (Photo: Anton Novoderezhkin/TASS/Getty)

Plastic bottles have a significant impact on the environment, requiring large amounts of energy to manufacture and causing huge damage to wildlife – and potentially to humans – as they break down into ever smaller components after use.

But the total environmental impact for glass bottles is much higher when factors such as their contribution to climate change through energy use and damage from mining for key ingredients is factored in, finds the study.

“A massive amount of energy is needed to heat the raw materials to make glass. During the melting of the raw materials for glass, gas pollutants can be released such as sulphur dioxide and carbon dioxide,” said Alice Brock, of Southampton University.

Large mining footprint

“And since glass requires materials to be mined for its production – silica sand, soda ash and dolomite – this has all the associated environmental impacts with mining such as land degradation and dust and runoff from the mines reaching water sources,” she said.

© Provided by The i Garbage, including plastic waste, is seen at the beach of the Costa del Este neighborhood in Panama City (Photo: Luis ACOSTA / AFP)

Silica sand mining can cause silicosis, a condition caused by tiny silica particles reaching the lungs, so there is also a considerable impact to human health, she says.

Around 20 per cent of the raw materials used to make glass are lost as CO2 and other gases.

One advantage of glass is that it is more durable than plastic. A typical glass bottle can typically be reused between 12 and 20 times before it is too damaged to be used, meaning it can be reused more often. Very often, however, they are thrown away after a single use.

Need to reuse glass bottles more

“I think the implications of this research are we really have to move to reuse bottles and cans. Just recycling isn’t enough. We need to change our mindset and move to things like refilling bottles, bottle return schemes and the like if we are going to cut these environmental impacts,” she said.

The environmental impacts in which glass outweighed plastic include contributions to climate change, freshwater toxicity, land toxicity, ocean acidification and freshwater eutrophication – when a body of water becomes overly enriched with minerals and nutrients which induce excessive growth of algae.

Tetra Pak-style fruit juice cartons, current milk cartons and 100 per cent aluminium cans are among the most environmentally-friendly containers, the study found.

“Despite being less impactful than the plastic bottles, both the milk carton and Tetra Pak still contain plastic elements,” Dr Brock said.

The study is published in the journal Detritus.