For centuries we have used glass to store food, beverages, chemicals and cosmetics. But is it time to find a more sustainable alternative?
Dating back to between 325 and 350 AD, the Speyer wine bottle is thought to be the world's oldest bottle of wine. Now held in the Wine Museum in the German city of Speyer, where it was rediscovered in 1867, an analysis of its contents revealed that it holds an ethanol-based liquid. But the glass bottle remains unopened and the vintage unknown. Any prospective wine tasters should be wary – preserved historic beverages can be pungent, to say the least.
The widespread use of glass as a storage vessel throughout history highlights the material's resilience and functionality. Glass is a useful material for everything from preserving food to carrying the signals that power the internet. So essential is glass to human development that the United Nations named 2022 the International Year of Glass to celebrate its contribution to cultural and scientific development.
Glass has sometimes been referred to as a material which can infinitely be recycled without it impacting its quality, purity or durability. Recycled glass can be crushed into glass cullets, which can be melted down and used to produce more glass. Glass used for packaging has a high recycling rate compared to other packaging materials. In Europe, the average glass recycling rate is 76%, compared to 41% for plastic packaging and 31% for wooden packaging.
When glass is left in the natural environment, it is less likely to cause pollution than plastic. Unlike plastics, which break down into microplastics that can leach into our soils and water, glass is non-toxic. "Glass is mainly made of silica, which is a natural substance," says Franziska Trautmann, the co-founder of Glass Half Full, a New Orleans-based company that recycles glass into sand that can be used for coastal restoration and disaster relief. Silica, also known as silica dioxide, makes up 59% of the Earth's crust. Since it is a natural compound, there is no concern about leaching or environmental degradation.