Water Resources Research Act Program

Details for Project ID 2020GA113B

Microplastics in wastewater effluent as a vehicle for bacterial and viral transport in an urban river

Institute: Georgia
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $17,924 Total Non-Federal Funds: $37,913

Principal Investigators: Lisa Casanova

Abstract: Microplastics, plastic polymers <5 mm, are ubiquitous in consumer productsincluding lotions, soaps, scrubs, and toothpastes. From consumer products, they enterinto wastewater. Conventional wastewater treatment can remove microplasticsefficiently, but MPs can still pass through treatment and be found frequently inwastewater effluent. MPs in water are readily colonized by microorganisms formingbiofilms, and may transport microorganisms in surface waters, including diseasecausingbacteria of humans and aquatic species. They do not degrade as naturalparticles can, making them potential vehicles for transport of microorganisms overlong distances and time periods.MP discharge into surface waters via wastewater effluent has been documented inurban rivers, but there is little research on MPs in effluent and rivers in Georgia. TheChattahoochee River is a heavily used and hugely influenced by human activity; amajor drinking water source for millions in the greater Atlanta area and beyond anda popular recreational water, it receives effluent from multiple municipal wastewatertreatment plants. It is an ideal site to explore MP sources, occurrence, and behaviorin Georgia rivers. Therefore, the goals of this project are:1. Measure and compare concentration of MPs in the Chattahoochee from waterupstream of two effluent outfalls (control sites), effluent directly from the twooutfalls, and water downstream of the two outfalls2. Characterize the total bacterial community and selected viruses free living inupstream water, outfall water, and downstream water3. Describe the total bacterial community and selected viruses colonizing surfacesof MPs in upstream, outfall, and downstream water.4. Compare bacterial community composition between sites and between waterand colonized MP surfaces.The concentration of MPs will be measured in effluent, upstream, and downstreamwater. These can be compared to determine if there are differences upstream vsdownstream of outfalls. Direct measurement of MPs in effluent will help determineif they are a potential source of MPs in river water. If very few MPs are found ineffluent compared to river water, this may suggest other common sources of MPs arecontributing to the river. In addition analysis of bacterial communities will determineif communities on MPs are similar across sampling sites, but different than those inriver water. Differences may suggest that MPs are transporting unique populationsof bacteria in the river. These distinct communities may also be a way to link MPs ineffluent to MPs in river water by examining community similarities. One of the firststeps in identifying and assessing emerging contaminants is to understand theiroccurrence, distribution, and transport; this project will help stakeholders decide ifMPs are emerging contaminants of concern in Georgia rivers.