Global distribution of human-associated fecal genetic markers in reference samples from six continents

RENÉ E. MAYER ; GEORG H. REISCHER ; SIMONE K. IXENMAIER ; JAMES E. EBDON ; RITA LINKE ; LUKAS EGLE ; WARISH AHMED ; ANICET R. BLANCH ; DENIS BYAMUKAMA ; MARION SAVILL; DOUGLAS MUSHI ; HÉCTOR A. CRISTÓBAL ; TOM EDGE; MARGIT A. SCHADE

ENVIRONMENTAL SCIENCE & TECHNOLOGY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2018 vol. 52 p. 5076 - 5084

0013-936X

Numerous bacterial genetic markers for the molecular detection of human sources of fecal pollution in environmental waters are available. However, widespread application is hindered by a lack of knowledge regarding geographical stability limiting implementation to a small number of characterized regions. This study investigates the geographic distribution of five human-associated genetic markers (HF183/BFDrev, HF183/BacR287, BacHum, BacH, and Lachno2) in municipal wastewaters (untreated and treated) from 29 urban and rural wastewater treatment plants situated across 13 countries spanning six continents. In addition, genetic markers were tested against 280 pooled human and non-human fecal samples from domesticated, agricultural and wild animal sources. Findings revealed that all genetic markers are highly concentrated in untreated (median log10 marker equivalents (ME) 7.2 - 8.0 100 ml-1) and secondary treated wastewater samples (median log10 4.6 - 6.0 ME 100 ml-1). Despite the fact that wastewater samples originated from different locations and human populations, genetic marker concentrations were remarkably consistent. However, the source-specificity of the various methods based on non-human fecal samples ranged from 95% to 48%. Despite large variation in source-specificity, results suggest that several genetic markers have great potential as tools for measuring human-associated contamination in polluted environmental waters across the globe.