Danimer Scientific’s polyhydroxyalkanoate (PHA) material was recognized as an eco-friendly alternative to petrochemical plastics by University of Georgia researchers and members of the UGA New Materials Institute. A study published in Environmental Science & Technology found the PHA biodegrades in aerobic and anaerobic environments like a landfill, waste treatment facility, or the ocean.

“The results of the study indicate that PHA is a dependable and biodegradable plastic for food packaging and other consumer applications,” says Scott Tuten, chief marketing officer at Danimer. “Many single-use products, such as straws, are under scrutiny or even banned because of their environmental impact at the end of their lifecycle. Our team remains dedicated to helping companies find the quality, sustainable materials that fit their needs. This issue quite literally affects the entire world, so we were grateful for the opportunity to supply UGA with samples of PHA to explore what happens to the material in different environments.”

Researchers at UGA measured the gaseous carbon loss of PHA samples placed in anaerobic sludge after 40 to 60 days of incubation and compared the levels to those of cellulose powder in the same setting. The anaerobic degradation of PHA was not significantly different from that of the cellulose powder, researchers discovered. The methane yields of PHA were found to be similar to that of food waste, meaning the material could be processed alongside common organic waste in a landfill.

Researchers also observed the gaseous carbon loss of PHA in seawater, simulating a situation in which plastic waste is deposited in an ocean. The study confirmed that if a solid form of PHA were to end up in such an environment, it would begin to biodegrade over the course of six months. Polypropylene pellets, a traditional plastic used as the negative control in the experiment, remained intact and unchanged during the same time period.

The final component of the study investigated the microbial diversity of both experiments to identify the bacteria present when PHA degrades. In anaerobic sludge conditions, Cloacamonales and Thermotogales were the dominant bacteria. In aerobic seawater conditions, Gemmatales and Phycisphaerales were the most enriched forms of bacteria. Researchers concluded that future studies would have to include expanded microbial analysis of PHA degradation, which will ultimately help guide the design of more efficient waste management systems.

“As governments and businesses consider alternatives to traditional plastics for everything from straws to food packaging, it is important to have a thorough understanding of the impact that different materials will have on various environments,” says Shunli Wang, Ph.D., a postdoctoral research associate at UGA’s College of Engineering. “Our study is among the first to comprehensively examine PHA, and results show that it has a relatively fast anaerobic biodegradation rate.”

Details of the research can be found here.