Plastics pollution is a problem in the oceans, but also in soils. However, we still do not know exactly how much of each polymer is emitted into the environment and from which sources.
Delphine Kawecki and Bernd Nowack, Empa − Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, have calculated the emissions of macro- and microplastics in Switzerland for seven different polymers. The team’s analysis included low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), expanded polystyrene (EPS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET)—all commonly used materials. To estimate the plastics pollution, the researchers analyzed the life-cycle of products containing these materials. They calculated emissions of both macro- and microplastics into water as well as soil. The modeling method they used is based on probabilistic material flow analysis (PMFA).
The team found that overall, more than 5 metric tons of plastics are released into the environment by the population of Switzerland every year. Most of this ends up in the soil, with macroplastics emissions of ca. 540 g per person per year and macroplastics emissions of ca. 73 g per person per year. Freshwater is polluted with a much smaller share of the plastics waste, i.e., ca. 13.3 g of macroplastics and ca. 1.8 g of microplastics per person per year.
The main contributor to plastics pollution is littering. Construction, agriculture, industrial processes, textiles, and personal care products cause most of the microplastics emissions. According to the researchers, more attention should be paid to plastics pollution on land, since 40 times more polymer waste ends up there compared with in waters. They also recommend a reduction of single-use plastics and measures against littering and waste mismanagement. Of course, regional differences in material flows need to be taken into account for other countries.
- Polymer-Specific Modeling of the Environmental Emissions of Seven Commodity Plastics As Macro- and Microplastics,
Delphine Kawecki, Bernd Nowack,
Environ. Sci. Technol. 2019.