Words Alia Fawaz
Wherever you look you will see something made of plastic. It’s not just the obvious food and beverage packaging but everything from electronic devices, utensils, and toys to toothbrushes – basically an endless list of things we have come to depend on every day. Despite its usefulness and durability, the ubiquitous plastic is causing lots of damage both to our environment and to our health. It takes anywhere from 500 to 1,000 years to degrade. And how can we ignore the infamous Pacific trash vortex: a massive area of plastic debris in the Pacific Ocean, which continues to kill wildlife and damage local ecosystems?
Plastic is mostly made from petroleum, and whether you manufacture it or destroy it by incineration, it pollutes. So, what is the solution to finding a safer, biodegradable material? Well, at first bioplastics were the answer: durable plastics made from renewable cellulose, a plant-based polysaccharide. However, the current bioplastics do not fully degrade in the environment. Their use is now limited to packaging material or simple containers for food and drink, as engineers have failed to mold these materials into complex 3D shapes that could be mass-produced and provide the hardness of everyday plastics.
Researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering may have an answer. They have actually introduced a new bioplastic that uses shells from shrimps and other crustaceans. In experiments with the material in shrimp shells, called chitosan, and material from silk, known as fibroin, they have combined the two and developed a material called “shrilk.”
The result is a tough, transparent material that can be used to manufacture large 3D objects with complex shapes using traditional casting or injection molding techniques. As a cheap, environmentally safe alternative to conventional plastic, shrilk could also be used to make trash bags, packaging, and diapers that break down in just a few weeks, while also releasing rich nutrients that can go on to support plant growth. In other words, the materials in shrilk make excellent fertilizer. Currently, the majority of shrimp shells are discarded or used in fertilizers, cosmetics, and dietary supplements.
In environmental terms, finding viable alternatives to conventional plastic is an urgent matter. One answer might be shrilk, if it can be produced cost-effectively and be successfully adopted by manufacturers. Scientists are also researching and developing other new substances that can potentially replace conventional plastic and be equally cheap to make.
Perhaps we need to approach plastic in the way that we are beginning to wean ourselves from our dependency on fossil fuels. As more nations are using a combination of renewable resources such as wind, solar energy, and water for generating power, we should also find different alternatives that collectively replace all plastic materials, and that are safer for us and for our environment. And maybe, just maybe, the plastic that we know today will one day be a thing of the past.