Greenhouse gases emitted from plastics in the environment

My newly published research demonstrates a previously unreported source of greenhouse gas pollution: plastic.

We found that the degradation and breakdown of plastic represents a previously unrecognized source of greenhouse gas pollution that is expected to increase—especially as more plastic is produced and accumulated in the environment.  


Perhaps this is not surprising, since, as most people know, plastic is basically oil…but the University of Hawaii is the first group publishing data about greenhouse gases and plastic debris, published August 1st at the online journal PLOS ONE The research has far-reaching implications for waste management of plastic, and terrestrial and ocean climate change impacts.


I looked at the most predominant types of plastic manufactured and littered globally. Of particular concern is the plastic type which releases gases at the highest rate: low-density polyethylene (LDPE), which is also the most prevalent plastic discarded in the ocean today. My research shows that as the surface area of the plastic increases due to weathering and break-down in the ocean, there is a tremendous increase in methane and ethylene off-gassing; for example, LDPE powders off-gases methane 488 times more than when the same weight of LDPE is in pellet form. 


Greenhouse gases directly influence climate change—affecting sea level, global temperatures, ecosystem health on land and in the ocean, and storms, which increase flooding, drought, and erosion. Considering the amounts of plastic washing ashore on our coastlines and the amount of plastic exposed to ambient conditions, the findings provide further evidence that to protect against climate change, we need to stop plastic production.