NEHA December 2022 Journal of Environmental Health

14 Volume 85 • Number 5 As more evidence mounts that E. coli levels are not necessarily associated with human health risks (Colford et al., 2007; Wade et al., 2010), it is important to bear in mind that elevated E. coli levels might not actually mean higher amounts of pathogens or feces. Future studies are necessary to address if the observed levels are associated with higher health risks and other indicators for fecal contamination. Additionally, other approaches to microbial source tracking—such as detecting viral markers through PCR amplification (Elkayam et al., 2018) or identifying chemical tracers (González-Fernández et al., 2021; Paruch & Paruch, 2021)—have been developed and could be used to complement the tools used in this study. More data regarding specific components of fecal contamination could provide additional information that would help determine sources that contribute to contamination and also assess the potential for human health risk. In addition to needing more reliable markers, this study highlights the importance of considering the properties of indicators when designing exploratory studies such as this one. As we used both live-culture and genetic markers to identify contamination, counts between these two diŒerent methods might have been more similar if samples had targeted flushes of fresh fecal contamination (e.g., after storm events). Collecting samples after a storm event could increase the chance of detecting fresh fecal matter, which would likely improve both the finding of a correlation between the general indicators and the detection of host-specific genetic markers that decay rapidly in the environment. Future studies should include more frequent water sampling associated with precipitation events and a more comprehensive sampling scheme to evaluate each watershed at multiple locations to pinpoint sources of contamination so that eŒective mitigation strategies can be instituted. DNA analysis can be an eŒective public health tool toward bacterial source identification that can aid in determining if source bacteria are a potential threat to public health and to guide remediation eŒorts. Further use of this technology should be evaluated, and its use considered by regulatory agencies as the DNA laboratory methodology is refined. Acknowledgements: This project was funded by CT DEEP through a CWA Section 319 Grant. Additional funding and in-kind services were provided by all authors. The authors would also like to extend a sincere thanks to Chris Malik of CT DEEP, Douglas Dingman of the Connecticut Agricultural Experiment Station, and Pete Fraboni of Earthplace for their valuable input throughout this water quality study. Corresponding Author: Michael A. Pascucilla, CEO/Director of Health, East Shore District Health Department, 688 East Main Street, Branford, CT 06405. Email: mpascucilla@esdhd.org. 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