SARS-CoV-2 Wastewater Surveillance for Public Health Action.

Wastewater surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has garnered extensive public attention during the coronavirus disease pandemic as a proposed complement to existing disease surveillance systems. Over the past year, methods for detection and quantification of SARS-CoV-2 viral RNA in untreated sewage have advanced, and concentrations in wastewater have been shown to correlate with trends in reported cases. Despite the promise of wastewater surveillance, for these measurements to translate into useful public health tools, bridging the communication and knowledge gaps between researchers and public health responders is needed. We describe the key uses, barriers, and applicability of SARS-CoV-2 wastewater surveillance for supporting public health decisions and actions, including establishing ethics consideration for monitoring. Although wastewater surveillance to assess community infections is not a new idea, the coronavirus disease pandemic might be the initiating event to make this emerging public health tool a sustainable nationwide surveillance system, provided that these barriers are addressed.

Spatial and temporal variability in atmospheric nitrous oxide generation and emission from full-scale biological nitrogen removal and non-BNR processes.

Biological nitrogen removal (BNR) strategies can contribute to atmospheric nitrous oxide (N2O). In the future, as BNR is implemented at more wastewater treatment plants (WWTPs) around the globe, the emission and release of these gases to the atmosphere is expected to increase. This study focused on the quantification of N2O emissions rates and inventory at several WWTPs using a newly developed, U.S. Environmental Protection Agency (Washington, D.C.) (U.S. EPA)-reviewed protocol. Application of the protocol revealed nitrous oxide emissions from aerated zones therein, hitherto not considered in the current U.S. EPA approach to quantifying N20 fluxes from WWTPs. A high degree of diurnal variability in N20 fluxes was measured, which correlated well with diurnal total Kjeldahl nitrogen loadings. In combination, these results point to the diminishing utility of a single emission factor approach to estimate the N2O emissions from WWTPs, which has been followed to date.