You are here:
Microbial Source Tracking Markers for Detection of Fecal Contamination in Environmental Waters: Relationships Between Pathogens and Human Health Outcomes
Citation:
Harwood, V., C. Staley, B. Badgley, K. Borges, AND A. Korajkic. Microbial Source Tracking Markers for Detection of Fecal Contamination in Environmental Waters: Relationships Between Pathogens and Human Health Outcomes. FEMS. Elsevier Science Ltd, New York, NY, 38(1):1-40, (2014).
Impact/Purpose:
This review article describes the current state of science in the Microbial Source Tracking field.
Description:
Microbial source tracking (MST) describes a suite of methods and an investigative strategy designed to identify the dominant sources of fecal pollution in environmental waters. The methods rely on the close association of certain fecal microorganisms with a particular host species or taxon for source attribution. MST is used to assess recreational water quality, human health risk from exposure to water, and total maximum daily load (TMDL) allocations. Methods that rely on signature molecules (markers) such as a DNA sequence of a host-associated microbe have largely replaced library-dependent methods, which require a large database from known fecal sources. Human sewage pollution generally receives the strongest mandate for identification and remediation due to 1) the known risk of exposure to human waste, and 2) the public and regulatory will to reduce sewage pollution. Although human sources have been the primary focus of method development, methods to identify animal sources are receiving increasing attention. Here, we review the development and performance of MST methods, with particular emphasis on quantitative PCR (qPCR) methods for human source determination, and on method performance in initial reports and field studies. Relationships among the human-associated MST markers, fecal indicator bacteria levels, pathogen presence, and human health outcomes are discussed and recommendations for future research are presented. An integrated understanding of the advantages and drawbacks of the many MST methods targeting human sources that have proliferated over the past several decades will benefit managers, regulators, researchers, and other users of this rapidly growing area of environmental microbiology.
