Grantee Research Project Results
Microplastics Sampling for Stormwater Management
EPA Grant Number: SU840579Title: Microplastics Sampling for Stormwater Management
Investigators: Bathi, Jejal R , Devries, Stephanie , Sreenivas, Kidambi
Institution: University of Tennessee at Chattanooga
EPA Project Officer: Brooks, Donald
Phase: I
Project Period: August 1, 2023 through July 31, 2024
Project Amount: $24,997
RFA: 19th Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet Request for Applications (RFA) (2022) RFA Text | Recipients Lists
Research Category: P3 Awards
Description:
The development of our proposed sampling and analysis protocol will be designing sampling equipment with multiple removable stainless-steel mesh screens of different sizes that will be stacked on top of each other for in situ fractionation of MPs. Additionally, the proposal will allow for further characterization and quantification of MPs on a microscopic level, since the plastics will already be separated into different sizes. As a first step of the protocol development, sampling equipment design will be optimized for fluid dynamics and MP collection efficiency by using computer simulations with the computational fluid dynamics Analysis of Systems (ANSYS) program. As a second step, quality control of the fabricated equipment will test for the efficiency of MP collection in our laboratory using MP spiked Milli-Q water samples. As a third step, the validated sampling equipment will be used to conduct paired sampling (influent and effluent) of stormwater green infrastructure controls (bioretention and grass wale) at the City of Chattanooga’s facilities. Finally, the collected MPs will be characterized for their size, dimensions, and types using a state-of-the-art Dynamic Light Scattering (DLS) device, Fourier-transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and under a stereomicroscope using the Nile Red method. In addition to significant learning for students involved in this project, a separate course module will be developed to be included in the Urban Stormwater Management class taught at the undergraduate and graduate levels.
Objective:
Increased use of plastics has merited concern for microplastic (MP) (< 5,000 µm) contamination which is considered a potential public health risk factor. The dearth of environmental occurrence data on microplastics (MPs) is impeding the discernment of their fate and transport kinetics, which is essential MPs mitigation, especially at environmentally relevant concentrations. Ill-suited techniques for sampling stormwater runoff and the flows from stormwater controls are limiting not only quantification but also evaluation and optimization of controls for MPs mitigation in the runoff. Our proposed research is to design a sampling device and develop a standard method to sample, extract, detect, and quantify MPs in stormwater runoff. The validated sampling method will demonstrate quantification of the performance of stormwater controls for MPs mitigation. Additionally, this research provides research opportunities to undergraduate students of diverse backgrounds.
Expected Results:
This proposed research will result in a standard protocol to sample and characterize MPs in stormwater runoff and will quantify and characterize the MPs in the effluent of stormwater controls. Through quantification of MPs in stormwater effluents, the research will quantify the relative efficiency of stormwater treatment techniques relative to MP mitigation, hence helping stakeholders choose the right technique for the control of emerging MPs pollution. In addition to training and developing educational modules for university-level students, all results will be disseminated to collaborators at the City of Chattanooga and through the Center for Urban Informatics and Progress (CUIP), a public-private partnership housed at UTC, and its partners.
Supplemental Keywords:
plastics sampling; emerging contaminants; stormwater pollution; green infrastructure; plankton tow netThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.