Microplastics, the small and pervasive remnants of plastic, have emerged as a critical environmental concern due to their widespread presence and detrimental effects. Originating from various sources in our plastic-dependent lifestyle, these minute particles pose significant challenges as they accumulate in the environment.

Researchers develop biodegradable microplastics

Typically smaller than five millimeters, microplastics, are highly durable and persist in the environment for extended periods. They fracture into smaller pieces over time and have been found in remote locations worldwide, from deep ocean trenches to mountain peaks. It is important to note that microplastics are infiltrating the food chain and human bodies.

A team of researchers from the University of California-San Diego and Algenesis, a materials-science company, claim to have created a biodegradable plastic derived from sources like algae. This innovative plastic breaks down in a few months, including into microplastics, potentially offering a solution to the environmental issues caused by traditional plastics.

The study in Scientific Reports reveals the effectiveness of an innovative material named TPU-FC1, derived from algae, in comparison to traditional plastics. Unlike petroleum-based polymers, TPU-FC1’s chemical structure, primarily polyurethane with ester and urethane linkages, is more susceptible to hydrolysis. This makes it easier for microbes in the environment, equipped with enzymes capable of breaking down these bonds, to decompose the plastic into its constituent parts for consumption.

Microbes mineralizing biodegradable TPU-FC1

Researchers tested the biodegradability of TPU-FC1 by grinding it into microplastic-sized particles and mixing it into active compost. Various methods were employed to monitor the fate of these particles over time. After 90 days, approximately 70 percent of the TPU-FC1 microplastics had decomposed. By 200 days, only 3% of the TPU-FC1 remained, indicating significant degradation by microbes. In contrast, microplastics made from conventional plastic, ethylene vinyl acetate (EVA), showed no degradation over the same period.

Scientists measured compost respiration to determine CO2 production by microbes consuming plastic. Results showed TPU-FC1 compost produced CO2 levels akin to cellulose, indicating microbial breakdown and mineralization of plastic, completing the carbon cycle.