This plastic-free bag dissolves in water

The humble plastic bag has been with us since 1965, when a team of Swedish designers and engineers hit upon an idea for convenient packaging. Just over 50 years later, as many as 4 trillion plastic bags are thought to be used each year.

They’re piling up fast, and we’ll be stuck with them littering the planet for hundreds of years because they don’t biodegrade.

Could that be about to change?

Researchers in Chile have created a bag that looks and behaves just like any other plastic bag, but with a couple of important differences. This bag is not made of plastic, and unlike regular plastic bags it will dissolve in water, leaving no toxic residue behind.

As with many great discoveries, the soluble bag was not what its creators had in mind to begin with. The two men behind the SoluBag, Roberto Astete and Cristian Olivares, were working on biodegradable detergent experiments. But when they created a formula that, by using a derivative of limestone instead of oil byproducts, changed the structure of plastic from indestructable to soluble, they realized they had found something significant.

In August, Chile became the first country in South America to issue an outright ban on the use of plastic bags, joining others including Rwanda and Jamaica, to take action against plastic pollution.

The material they have created can be used to produce an alternative to a wide range of plastic items, with bags the first target in their sights. While a traditional plastic bag will take over 150 years to degrade, the SoluBag can be disposed of safely in water in just minutes.

So safely, in fact, that Astete gave a demonstration – placing a bag in a jar of water, stirring it to get it to dissolve, then drinking some of the water. It’s an echo of a development made by a team in Indonesia in May of this year, who have invented an alternative plastic bag from cassava. These developments could be particularly significant in the fight against marine pollution.

Plastic that ends up in the sea begins to break down into smaller pieces as a result of wave erosion and other environmental effects, such as the action of bacteria. A lot of plastic products are treated with additional chemicals to enhance their longevity – things like UV resistance, antimicrobial qualities, or flame-retardance. These chemical additives can leak into the environment, in addition to the problem of microplastic particles being consumed by marine life and entering the global food chain.

According to the United Nations Environmental Programme, every square kilometre of the sea is likely to contain over 60,000 microplastic particles, and in some parts of the world that number is considerably higher. While the Earth Day Network estimates that “32% of the 78 million tons of plastic packaging produced annually is left to flow into our oceans.”

So any measures that limit the amount of discarded plastic entering rivers and oceans can only be a good thing. The more likely something is to completely biodegrade the less likely it is to become a hazard.

According to Astete and Olivares, the SoluBag’s only residue is carbon. Their regular bag dissolves in cold water. But they also have a reusable fabric-lined version that dissolves in hot water. And don’t worry about what might happen if you get caught in the rain while using one, the bag’s creators claim the new material can be made to respond to warm water only.