Sludge Watch ==> Triclosan, Triclocarban good markers for sewage - sludge

[Maureen Reilly]

Sludgewatch Admin:
*with thanks to Dan


In the past it was thought that caffeine was the ideal marker for tracking 
the movement of contaminates through the sewage system. For many years Rolf 
Halden and crew had studied these 2 synthetic chemicals in sludge. They've 
now published a paper on treated wastewater. Triclosan and Triclocarban are 
found in all antibacterial soaps and detergents commonly used by the 
majority of people today. Just a reminder, these 2 items are proven 
endocrine disruptors.

ACS Publications - April 5, 2008
It is concluded that chemical monitoring of microbial risks is more 
effective when using hydrophobic OWCs such as triclosan and triclocarban in 
place of, or in conjunction with, the traditional marker caffeine.



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http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es702591r.html

http://www.americanscientist.org/template/AssetDetail/assetid/54434


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ASAP Environ. Sci. Technol., ASAP Article, 10.1021/es702591r
Web Release Date: April 5, 2008
Copyright © 2008 American Chemical Society
Ab Initio and in Situ Comparison of Caffeine, Triclosan, and Triclocarban as 
Indicators of Sewage-Derived Microbes in Surface Waters
Thayer A. Young,† Jochen Heidler,† Cristina R. Matos-Pérez,† Amir 
Sapkota,† Tanikka Toler,† Kristen E. Gibson,† Kellogg J. Schwab,† 
and Rolf U. Halden*†‡
Johns Hopkins University Center for Water and Health, Department of 
Environmental Health Sciences, Bloomberg School of Public Health, Johns 
Hopkins University, Baltimore, Maryland 21205, and Center for Environmental 
Biotechnology, The Biodesign Institute, Arizona State University, Tempe, 
Arizona 85287
Received for review October 13, 2007
Revised manuscript received February 8, 2008
Accepted February 18, 2008


Abstract:
Three organic wastewater compounds (OWCs) were evaluated in theory and 
practice for their potential to trace sewage-derived microbial contaminants 
in surface waters. The underlying hypothesis was that hydrophobic OWCs 
outperform caffeine as a chemical tracer, due to their sorptive association 
with suspended microorganisms representing particulate organic carbon (POC). 
Modeling from first principles (ab initio) of OWC sorption to POC under 
environmental conditions suggested an increasing predictive power: caffeine 
(0.2% sorbed) < triclosan (9–60%; pH 6–9) < triclocarban (76%). 
Empirical evidence was obtained via analysis of surface water from three 
watersheds in a rural-to-urban gradient in Baltimore, MD.

Mass spectrometric OWC detections were correlated to microbial plate counts 
for 40 monitoring sites along 14 streams, including multiple chronic sewage 
release sites and the local wastewater treatment plant. Consistent with ab 
initio calculations, correlation analyses of 104 observations for fecal 
coliforms, enterococci, and Escherichia coli in natural surface waters 
showed that the particle-active antimicrobials triclosan and triclocarban 
(R2 range, 0.45–0.55) were indeed superior to caffeine (0.16–0.37) for 
tracking of microbial indicators.

It is concluded that chemical monitoring of microbial risks is more 
effective when using hydrophobic OWCs such as triclosan and triclocarban in 
place of, or in conjunction with, the traditional marker caffeine.