Plastics munch-on by soil bugs

Presently, our world is sinking in a plastic flood. Every year eight million tons of plastic drowns in the ocean. There are many agriculture soils threatened by the pollution of plastic. Farmers around the world apply various amounts of polyethylene (PE) mulch films onto soils to protect weeds, keep the soil moist and maximize soil temperature to increase overall crop yields. 

After harvesting, it is impossible for farmers to recollect the complete films, particularly when films are a few micrometers thin. Film debris makes its path to the soil and accumulates in the soil within a period. This is because PE does not biodegrade. Film residues of soil reduce soil fertility, interfere with water transport and eliminate crop growth. 

Researchers at ETH Zurich and the Swiss Federal Institute of Aquatic Science and Technology (Eawag) have shown some studies and demonstrate about soil microbes degrade films composed of the substitution of polymer poly(butylene adipate-co-terephthalate) (PBAT). Their work published in the scientific advances journal. 

Michael Sander, Kristopher McNeill and Hans-Peter Kohler, former ETH doctoral student Michael Zumstein coordinated in the research project in demonstrating about the microorganism soil metabolically used the carbon in the PBAT polymer. These are used for both builds up microbial biomass and for energy production. 

Michael Sander, Senior Scientist in the Environmental Chemistry Group in the Department of Environmental Systems Science at ETH Zurich says that this research demonstrates directly for the first time about the microorganisms mineralize soil PBAT film in soil and transfer carbon from the polymer to biomass. 

PBAT is a petroleum-based polymer. It is used to make different products, including more films. PBAT was classified as biodegradable in compost. The ETH and Eawag researchers focused on assessing PBAT biodegrades in agricultural soils. This comparison, PE does not biodegrade in compost or in the soil. The researchers wished that the study will be noticed by the industry. They have developed analysis techniques that open the door of the industry to test the impact of plastic products in the environment. Co-author Kristopher McNeill says that they are thinking to the method and they can switch to using biodegradable materials in the production of thin films rather than non-degradable PE. 

Only some of the chemical companies have started to create and market eco-friendly, but expensive PBAT films. Among that German company, BASF supported this study. In addition to this, the volume of plastic has to reduce in entering the agricultural soils can employ thicker much films. These are used in Swiss agriculture.