What is Source Tracking and Why is it Important?

Microbial source tracking (MST) techniques detect fecal-associated microbes in aquatic systems. Coastal areas can experience elevated levels of fecal microbes from multiple sources, including human (e.g., septic systems, wastewater treatment plants) and non-human (e.g., wildlife, livestock, domesticated pets). These fecal sources can convey potential pathogens to waterways, posing human health risks through contaminated fisheries and recreational waters. 

Since there are various ways in which fecal contamination can be introduced to waters, management of contamination can become difficult if source(s) are unknown. Therefore, reliable and efficient source tracking methods are needed to manage fecal contamination for the protection of human health. However, MST tools vary in ability and effort. 

Not all MST tools are able to distinguish between human and non-human sources of fecal contamination. Molecular methods (e.g., quantitative PCR and eDNA) are capable of identifying the source(s) of fecal contamination, allowing for more effective management of a system. 

Application of the eDNA Source Tracking Toolkit will allow for comprehensive assessments of water quality through community composition and function, filling in data gaps left by source-specific microbial source tracking methods, such as qPCR.