Minimal Impacts of Microplastics on Soil Physical Properties under Environmentally Relevant Concentrations
- Washington State University, Pullman, WA (United States)
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
Agricultural soils are a major reservoir of microplastics, and concerns have arisen about the impacts of microplastics on soil properties and functioning. In this report we measured the physical properties of a silt loam in response to the incorporation of polyester fibers and polypropylene granules over a wide range of concentrations. We further elucidated the underlying mechanisms through determining the role of microplastic shape and the baseline effects from the amendment of soil particles. The incorporation of microplastics into soil tended to increase contact angle and saturated hydraulic conductivity, decrease bulk density and water holding capacity, while did not affect aggregate stability. Polyester fibers affected soil physical properties more profoundly than polypropylene granules, due to the vastly different shape of fibers from that of soil particles. However, changes in soil properties were gradual, and significant changes did not occur until a high concentration of microplastics was reached (i.e., 0.5% w/w for polyester fibers and 2% w/w for polypropylene granules). Currently, microplastic concentrations in soils not heavily polluted with plastics are far below these concentrations, and results from this study suggest that microplastics at environmentally relevant concentrations have no significant effects on soil physical properties.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Biological and Environmental Research (BER); National Institute of Food and Agriculture (USDA)
- Grant/Contract Number:
- AC05-76RL01830; 2020-67019-31167/1022800
- OSTI ID:
- 1970156
- Report Number(s):
- PNNL-SA-183046
- Journal Information:
- Environmental Science and Technology, Vol. 57, Issue 13; ISSN 0013-936X
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Utilization of high calcium fly ash as a substitute for limestone in agricultural soils
Influence of living grass Roots and endophytic fungal hyphae on soil hydraulic properties