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Abstract Particle size greatly influences the fate of phosphorus (P) in estuaries as P adheres more readily to the larger surface area in smaller sized particles. Here, data on two size fractions of particulate matter, permanently suspended particulate matter (PSPM, ≤40 μm) and resuspended particulate matter (RSPM, >40 μm), from field and controlled laboratory erosion experiments were analyzed to determine their relative contribution to water column P in the mouth of the Susquehanna River in the upper Chesapeake Bay. Based on the composition of sequentially extracted P pools, C and N isotopes, and elemental data, all PSPM and the majority of RSPM are most likely derived from allochthonous sources through river transport. A minor fraction of particulate matter in the water column was derived from sediment resuspension, which had a dominant role above the sediment‐water interface in the river's mouth. The proportion of biologically available P pools to recalcitrant P pools in suspended particulate matter decreased with water column depth, indicating their preferential removal or biological utilization during settling. Suspended particulate matter (SPM) mobilized during sediment erosion experiments, regardless of particle size, was richer in biologically available P pools than SPM in the field, suggesting higher mobility of these pools in the field. These complementary results from field and field‐simulated laboratory erosion experiments provide unique insights into the composition of particulate matter under different hydrodynamic regimes in the river estuary.
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Particle association and size fraction of molecular viral fecal pollution indicators in wastewater
Fecal indicator bacteria currently used for water quality monitoring inadequately represent viral fate in water systems, motivating the development of viral fecal pollution indicators. Molecular viral fecal pollution indicators such as crAssphage and pepper mild mottle virus (PMMoV) have emerged as leading viral fecal pollution indicator candidates due to ease and speed of measurement and target specificity. Elucidating the fate of molecular viral fecal indicators in water systems is necessary to facilitate their development, broader adoption, and ultimately their association with infectious risk. A significant mechanism controlling the behavior of viral indicators in environmental waters is association with particles, as this would dictate removal via settling and transport characteristics. In this study, we investigated the particle associations of six molecular fecal pollution targets (crAssphage, PMMoV, adenovirus, human polyomavirus, norovirus, HF183/BacR287) in wastewater using a cascade filtration approach. Four different filters were employed representing large settleable particles (180 μm), larger (20 μm) and smaller suspended particles (0.45 μm), and non-settleable particles (0.03 μm). All molecular targets were detected on all particle size fractions; however, all targets had their highest concentrations on the 0.45 μm (percent contribution ranging from 40% to 80.5%) and 20 μm (percent contribution ranging from 3.9% to 39.4%) filters. The association of viral fecal pollution targets with suspended particles suggests that particle association will dictate transport in environmental waters and that sample concentration approaches based upon particle collection will be effective for these targets.
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- Award ID(s):
- 1748019
- PAR ID:
- 10410209
- Date Published:
- Journal Name:
- Environmental Science: Water Research & Technology
- Volume:
- 8
- Issue:
- 9
- ISSN:
- 2053-1400
- Page Range / eLocation ID:
- 1814 to 1821
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Human exposure to pathogenic viruses in environmental waters results in a significant global disease burden. Current microbial water quality monitoring approaches, mainly based on fecal indicator bacteria, insufficiently capture human health impacts posed by pathogenic viruses in water. The emergence of the ‘microbiome era’ and high-throughput metagenome sequencing has led to the discovery of novel human-associated viruses, including both pathogenic and commensal viruses in the human microbiome. The discovery of novel human-associated viruses is often followed by their detection in wastewater, highlighting the great diversity of human-associated viruses potentially present in the water environment. Novel human-associated viruses provide a rich reservoir to develop viral water quality management tools with diverse applications, such as regulating wastewater reuse and monitoring agricultural and recreational waters. Here, we review the pathway from viral discovery to water quality monitoring tool, and highlight select human-associated viruses identified by metagenomics and subsequently detected in the water environment (namely Bocavirus, Cosavirus, CrAssphage, Klassevirus, and Pepper Mild Mottle Virus). We also discuss research needs to enable the application of recently discovered human-associated viruses in water quality monitoring, including investigating the geographic distribution, environmental fate, and viability of potential indicator viruses. Examples suggest that recently discovered human pathogens are likely to be less abundant in sewage, while other human-associated viruses (e.g., bacteriophages or viruses from food) are more abundant but less human-specific. The improved resolution of human-associated viral diversity enabled by metagenomic tools provides a significant opportunity for improved viral water quality management tools.more » « less
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null (Ed.)Microbial contamination of recreation waters is a major concern globally, with pollutants originating from many sources, including human and other animal wastes often introduced during storm events. Fecal contamination is traditionally monitored by employing culture methods targeting fecal indicator bacteria (FIB), namely E . coli and enterococci, which provides only limited information of a few microbial taxa and no information on their sources. Host-associated qPCR and metagenomic DNA sequencing are complementary methods for FIB monitoring that can provide enhanced understanding of microbial communities and sources of fecal pollution. Whole metagenome sequencing (WMS), quantitative real-time PCR (qPCR), and culture-based FIB tests were performed in an urban watershed before and after a rainfall event to determine the feasibility and application of employing a multi-assay approach for examining microbial content of ambient source waters. Cultivated E . coli and enterococci enumeration confirmed presence of fecal contamination in all samples exceeding local single sample recreational water quality thresholds ( E . coli , 410 MPN/100 mL; enterococci, 107 MPN/100 mL) following a rainfall. Test results obtained with qPCR showed concentrations of E . coli , enterococci, and human-associated genetic markers increased after rainfall by 1.52-, 1.26-, and 1.11-fold log 10 copies per 100 mL, respectively. Taxonomic analysis of the surface water microbiome and detection of antibiotic resistance genes, general FIB, and human-associated microorganisms were also employed. Results showed that fecal contamination from multiple sources (human, avian, dog, and ruminant), as well as FIB, enteric microorganisms, and antibiotic resistance genes increased demonstrably after a storm event. In summary, the addition of qPCR and WMS to traditional surrogate techniques may provide enhanced characterization and improved understanding of microbial pollution sources in ambient waters.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2EW00126H
