You are here:
Variable Fecal Source Prioritization in Recreational Waters Routinely Monitored with Viral and Bacterial General Indicators.
Citation:
Li, X., Mano Sivaganesan, AND O. Shanks. Variable Fecal Source Prioritization in Recreational Waters Routinely Monitored with Viral and Bacterial General Indicators. ASM Microbe 2022, Washington, DC, June 09 - 13, 2022.
Impact/Purpose:
Fecal pollution is the number one biological contaminant in U.S. surface waters with polluted sites in every state. When present, fecal waste can pose a serious public health risk and can lead to severe economic burdens, especially in communities that rely on clean and safe water. Fecal pollution can originate from untreated sewage due to combined sewer overflows, spills, and leaky infrastructure. In response to this nationwide need, the U.S. EPA ORD maintains an active research program to develop, validate, implement, and provide technical support for tools to characterize fecal pollution sources in environmental waters. Information covered in this manuscript was prepared based on high priority research needs in the EPA Research Action Plan (SSWR Research Area 3, Output #1, Product 1).
Description:
Somatic and F+ coliphage methods are under consideration as potential routine surface water quality monitoring tools to identify unsafe levels of fecal pollution in recreational waters. However, little is known about the cooccurrence of these virus-based fecal indicators and host-associated genetic markers used to characterize pollution sources. In this study, paired measurements of cultivated coliphage (somatic and F+) and bacterial (E. coli and enterococci) general fecal indicators and genetic markers indicative of human (HF183/BacR287 and HumM2), ruminant (Rum2Bac), canine (DG3), and avian (GFD) fecal pollution sources were assessed in 365 water samples collected from six Great Lakes Basin beach and river sites over a 15-week recreational season. Water samples were organized into groups based on defined viral and bacterial fecal indicator water quality thresholds and average log10 host-associated genetic marker fecal score ratios were estimated to compare pollutant source inferences based on variable routine water quality monitoring practices. Eligible log10 fecal score ratios ranged from -0.051 (F+ coliphage, GFD) to 2.08 (enterococci, Rum2Bac). Findings suggest that general fecal indicator selection for routine water quality monitoring can influence the interpretation of host-associated genetic marker measurements, in some cases, prioritizing different pollutant sources for remediation. Variable trends were also observed between Great Lake beach and river sites suggesting disparate management practices may be useful for each water type.