Project Info

Nanoplastics in the Environment: The Analysis Challenge

Kim Williams | krwillia@mines.edu

The global total of plastic waste is estimated to be 6300 million tons, the majority of which has been generated since 1950.[1] There is a wealth of literature that demonstrates plastic debris fractures into micro (< 5000 μm) sized particles and fibers that migrate into the food chain and consumer products.[2–7] For many years it has been assumed that plastics may further degrade into nano (< 0.1 μm) scale materials, however, without suitable standards and characterization methods there has been little progress in this area of research.[2,4] It was only recently that a study has shown that microplastics collected from the North American gyre may further photodegrade into nano-scale materials.[8] Current sampling procedures for environmental risk assessment of microplastics use mesh with pore sizes large enough to exclude the capture of nanoplastics.[2,9] Even if collected fractions do contain nanoplastics, the methods of detection may cause aggregation due to heat treatment or the limits of detection are too high for analysis.[2,4,10]
Our Laboratory for Advanced Separations Science and Technology (LAST) is uniquely suited to study nanoscale materials. We are a leader and innovator in field-flow fractionation (FFF), which has become an increasingly important tool for researchers with nanoscale analytical challenges. One such challenge is studying the effects of plastic pollution on the environment and the food chain. The FFF family of instruments is well-suited for materials that frustrate traditional chromatography methods and the open channel design removes a number of complicating factors from the analysis.[11] The use of FFF, online instrumentation, and microscopy allow us to fully characterize nanoplastics in a way that only few labs in the world are capable of at present. This project will focus on the development of analytical methods to help address the nanoplastics challenge.

More Information

(1) Ng, E. L.; Huerta Lwanga, E.; Eldridge, S. M.; Johnston, P.; Hu, H. W.; Geissen, V.; Chen, D. An Overview of Microplastic and Nanoplastic Pollution in Agroecosystems. Sci. Total Environ. 2018, 627, 1377–1388.
(2) Panel, E.; Chain, F. Presence of Microplastics and Nanoplastics in Food, with Particular Focus on Seafood. EFSA J. 2016, 14 (6).
(3) Yang, D.; Shi, H.; Li, L.; Li, J.; Jabeen, K.; Kolandhasamy, P. Microplastic Pollution in Table Salts from China. Environ. Sci. Technol. 2015, 49 (22), 13622–13627.
(4) Bouwmeester, H.; Hollman, P. C. H.; Peters, R. J. B. Potential Health Impact of Environmentally Released Micro- and Nanoplastics in the Human Food Production Chain: Experiences from Nanotoxicology. Environ. Sci. Technol. 2015, 49 (15), 8932–8947.
(5) Remy, F.; Collard, F.; Gilbert, B.; Compère, P.; Eppe, G.; Lepoint, G. When Microplastic Is Not Plastic: The Ingestion of Artificial Cellulose Fibers by Macrofauna Living in Seagrass Macrophytodetritus. Environ. Sci. Technol. 2015, 49 (18), 11158–11166.
(6) Duis, K.; Coors, A. Microplastics in the Aquatic and Terrestrial Environment: Sources (with a Specific Focus on Personal Care Products), Fate and Effects. Environ. Sci. Eur. 2016, 28 (1), 1–25.
(7) Webb, H. K.; Arnott, J.; Crawford, R. J.; Ivanova, E. P. Plastic Degradation and Its Environmental Implications with Special Reference to Poly(Ethylene Terephthalate). Polymers (Basel). 2013, 5 (1), 1–18.
(8) Gigault, J.; Pedrono, B.; Maxit, B.; Ter Halle, A. Marine Plastic Litter: The Unanalyzed Nano-Fraction. Environ. Sci. Nano 2016, 3 (2), 346–350.
(9) Hidalgo-Ruz, V.; Gutow, L.; Thompson, R. C.; Thiel, M. Microplastics in the Marine Environment: A Review of the Methods Used for Identification and Quantification. Environ. Sci. Technol. 2012, 46 (6), 3060–3075.
(10) Zhang, S.; Yang, X.; Gertsen, H.; Peters, P.; Salánki, T.; Geissen, V. A Simple Method for the Extraction and Identification of Light Density Microplastics from Soil. Sci. Total Environ. 2018, 616–617, 1056–1065.
(11) Williams, S. K. R.; Runyon, J. R.; Ashames, A. A. Field-Flow Fractionation: Addressing the Nano Challenge. Anal. Chem. 2011, 83 (3), 634–642.

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