Impacts of the COVID-19 pandemic on pharmaceuticals in wastewater treated for beneficial reuse: Two case studies in central Pennsylvania

Authors: HAYDEN, KATHRYN - Pennsylvania State University; JONES, MATTHEW - Pennsylvania State University; Elkin, Kyle; SHREVE, MICHAEL - Pennsylvania State University; CLEES II, WILLIAM - Pennsylvania State University; CLARK, SHIRLEY - Pennsylvania State University; MASHTARE, MICHAEL - Pennsylvania State University; Veith, Tameria - Tamie; ELLIOTT, HERSCHEL - Pennsylvania State University; WATSON, JOHN - Pennsylvania State University; SILVERMAN, JUSTIN - Pennsylvania State University; RICHARD, THOMAS - Pennsylvania State University; READ, ANDREW - Pennsylvania State University; PREISENDANZ, HEATHER - Pennsylvania State University

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/5/2022
Publication Date: 9/5/2022
Citation: Hayden, K.R., Jones, M., Elkin, K.R., Shreve, M.J., Clees II, W.I., Clark, S., Mashtare, M.L., Veith, T.L., Elliott, H.A., Watson, J.E., Silverman, J., Richard, T.L., Read, A.F., Preisendanz, H.E. 2022. Impacts of the COVID-19 pandemic on pharmaceuticals in wastewater treated for beneficial reuse: Two case studies in central Pennsylvania. Journal of Environmental Quality. 51(5):1066–1082. https://doi.org/10.1002/jeq2.20398.
DOI: https://doi.org/10.1002/jeq2.20398

Interpretive Summary: It is known that wastewater treatment plants were not designed to remove trace-level concentrations of medications, and therefore the active ingredients in these medicines can be found in the wastewater treatment plant effluent. When that effluent is beneficially reused for irrigation, pharmaceutical compounds are inadvertently introduced into the agricultural landscape, where they can impact nearby surface water, groundwater, or be taken up by crops. This study looks at how the usage of pharmaceuticals over the course of the COVID-19 pandemic affected the quality of water produced for irrigation. Objectives of the study were 1) to understand relationships between medications in wastewater and both SARS-CoV-2 and related hospitalization data; 2) to understand potential environmental risks from pharmaceuticals in wastewater that used for irrigation; and 3) to compare effluent to influent concentrations to understand how newly-created medications pass through the wastewater treatment process. We collected weekly influent and effluent samples from May 2020 through May 2021 from two wastewater treatment plants in central Pennsylvania. The samples were analyzed for the SARS-CoV-2 virus and 10 pharmaceuticals, including two over-the-counter fever reducers, five antibiotics, and three hospital-grade pharmaceuticals used to treat COVID-19 patients. Data showed that the wastewater treatment plants were able to effectively remove SARS-CoV-2 prior, such that no virus remained in the treated effluent. However, novel pharmaceuticals used to treat COVID-19 patients did persist in the effluent, including dexamethasone and remdesivir. Further, patterns in the pharmaceutical data for one of the treatment plants followed decision-making from the University in the treatment plant’s service area, such that pharmaceuticals were absent or lower during times when classes were held remotely and were higher when students were brought back to campus for in-person classes again. Overall, the data helped to further connections between human health and water quality and further demonstrate the utility of wastewater surveillance.

Technical Abstract: During the COVID-19 pandemic, wastewater surveillance was leveraged as a powerful tool for monitoring community-scale health. Further, the well-known persistence of some pharmaceuticals through wastewater treatment plants spurred concerns that increased usage of pharmaceuticals during the pandemic would increase the concentrations in wastewater treatment plant effluent. By analyzing wastewater for SARS-CoV-2, prescription medications, and over-the-counter medications, valuable information regarding the well-being of an entire community can be gained without the need to interview, survey, or test individuals. Objectives of this research were to 1) investigate relationships between pharmaceuticals in wastewater and both SARS-CoV-2 and related hospitalization data; 2) understand potential ecological risks posed by pharmaceuticals in wastewater; and 3) compare effluent to influent concentrations to understand the persistence of novel pharmaceuticals through wastewater treatment. We collected weekly influent and effluent samples from May 2020 through May 2021 from two wastewater treatment plants in central Pennsylvania, the Penn State Water Reclamation Facility and the University Area Joint Authority, that provide effluent for beneficial reuse, including for irrigation. Samples were analyzed for SARS-CoV-2, two over-the-counter medicines (acetaminophen and naproxen), five antibiotics (ampicillin, doxycycline, ofloxacin, sulfamethoxazole, and trimethoprim), two therapeutic agents (remdesivir and dexamethasone), and hydroxychloroquine. While there were no correlations between pharmaceutical and virus concentration, remdesivir detection occurred when the number of hospitalized COVID-19 patients increased and dexamethasone detection co-occurred with the presence of COVID-19 patients on ventilators. Additionally, Penn State decision-making regarding instruction modes explained the temporal variation of influent pharmaceutical concentrations, with detection occurring primarily when students were on campus. Risk quotients calculated for pharmaceuticals with known EC50 or LC50 values for fish, daphnia, and algae were generally low in the effluent; however, some acute risks from sulfamethoxazole and dexamethasone were high when students returned to campus. Remdesivir and dexamethasone persisted through the wastewater treatment plants, thereby introducing novel pharmaceuticals directly to soils and surface water. These results highlight connections between human health and water quality and further demonstrate broad utility of wastewater surveillance.