The presence of plastics in the environment is viewed as an undesirable byproduct of modern life, but how much of this ubiquitous and long-lived material actually enters the world’s soils and waterways? Researchers from Empa — Swiss Federal Laboratories for Materials Science and Technology conducted a material flow Source: Empaanalysis to assess the emission flows of seven types of plastic into the aquatic and soil ecosystems of Switzerland.

The analysis considered littering, dumping and other emission sources of low-density polyethylene, high-density polyethylene, polypropylene, polystyrene, expanded polystyrene, polyvinyl chloride and polyethylene terephthalate. A distinction was also made for environmental pollution associated with microplastics, which are smaller than 5 mm, and larger particles classified as macroplastics.

With all seven polymers combined, 630 ± 150 g/per capita of plastic enters the environment per year. Modeled emissions to soil exceed emissions to freshwater for all polymers: 610 ± 150 g/per capita are emitted to soil and 15.1 ± 5.1 g/per capita are emitted to water. Of this amount, 1.8 ± 1.1 g/per capita enters aquatic systems as microplastics and 13.3 ± 4.9 g/per capita enters water as macroplastics. For soils, the corresponding flows are 73 ± 14 g/per capita as microplastics and 540 ± 140 g/per capita as macroplastics. About 4,400 tons of macroplastics are deposited on soils every year, and about 100 tons of macroplastics are emitted to waters. Soils receive about 600 tons of microplastics while about 15 tons end up in waters.

Remedial measures suggested in Environmental Science & Technology include improved litter control campaigns, stronger regulation of single-use plastics and greater efforts to reduce combined sewer overflows.