Plastics Emit Greenhouse Gases as They Degrade

The materials are a previously unaccounted-for source of methane and ethylene, researchers find.

Aug 2, 2018

SHAWNA WILLIAMS

Need another reason to ditch straws? A study published yesterday (August 1) in PLOS ONE reports that plastics—ranging from construction materials to plastic bags—release the greenhouse gases methane and ethylene after being exposed to sunlight and beginning to degrade. 

“Our results show that plastics represent a heretofore unrecognized source of climate-relevant trace gases that are expected to increase as more plastic is produced and accumulated in the environment,” the study authors write in their paper.

The researchers, all based at the University of Hawai‘i at Manoa, tested the emissions of seven types of plastics as they degraded: polyethylene terephthalate, polycarbonate, high-density polyethylene and low-density polyethylene (LDPE), acrylic, polypropylene, and polystyrene. All gave off methane and ethylene in the days after being exposed to sunlight, they found, but polyethylene, which is used to make plastic bags, was the worst offender.

See full article at source:  https://www.the-scientist.com/news-opinion/plastics-emit-greenhouse-gases-as-they-degrade-64600