In a university lab near Guadalajara, Mexico, researchers have trimmed cactus leaves and put them into a juicer, creating a bright green liquid. When the liquid is mixed with other natural materials and processed, it undergoes an impressive transformation: The cactus juice becomes a biodegradable plastic.
The new plastic alternative, mostly comprised of juiced cactus leaves, rapidly biodegrades and doesn’t require crude oil like the traditional plastics do – which is a potentially less harmful way to package food and other goods.
“It’s a non-toxic product,” Sandra Pascoe Ortiz, the University of the Valley of Atemajac engineer who developed the material, “All the materials we use can be ingested both by humans or animals. And they wouldn’t cause any harm.”
Plastic made from cactus would not necessarily help stop the flow of trash into waterways. But the researchers say that the material biodegrades quickly and is non-toxic if it’s eaten. And unlike plastic made from fossil fuels, the cactus-based plastic is carbon neutral as it breaks down–the carbon dioxide it emits equals the carbon dioxide it took in as a plant as it grew.
It is one experiment to help deal with the world’s plastic problem. Around 19 billion pounds of plastic ends up in the ocean each year, and as plastic breaks down there and in landfills, it makes its way into the food system. People now eat an annual diet of more than 50,000 pieces of microplastic. The prickly pear cactus used in the experiment, which grows locally, is well suited to become plastic. “The cactus of these species contains large amounts of sugars and gums that favor the formation of the biopolymer,” says Sandra Pascoe Ortiz, a chemical engineering professor at the University of the Valley of Atemajac, who is leading the research.
The new material isn’t yet as long-lasting as plastic made from fossil fuels. But it could still be useful in some applications. “We are thinking of products that are disposable, single-use, or that do not need to be durable,” she says. It may also be more biodegradable than other alternatives; corn-based plastic, for example, is unlikely to break down unless it’s in an industrial composting facility, and most consumers still don’t have access to that type of facility. The cactus-based plastics can biodegrade in a backyard composter within a few months.
