Sludge Watch ==> The resistance movement - superbugs in sludge

[maureen.reilly at sympatico.ca]

Posted on Thu, Sep. 21, 2006
The resistance movement
By Steven Potter

Milwaukee Journal Sentinel

(MCT)

As the old adage goes, that which does not kill you, makes you stronger.

And although it's meant to inspire those facing hardship, that expression 
also applies to harmful bacteria that have become resistant to the 
disinfectant soaps and medicines once used to prevent and treat infections, 
scientists have found.

The development of these resistant bacteria has raised flags in the 
scientific and medical communities because of the potentially dangerous 
medical effect and possibly fatal impact they might have on plants, animals 
and people.

One environment encouraging the development of resistant bacteria is sewage 
treatment plants. Medicines and antibiotics not fully absorbed by our bodies 
are released in urine and fecal matter and then flushed down toilets, and 
antimicrobial disinfectant soaps are washed off into our sewer systems.

"Wastewater treatment plants are hot spots of microbial diversity, (which) 
includes a large variety of microbial pathogens," said Rolf Halden, 
assistant professor of environmental health sciences at the Johns Hopkins 
Bloomberg School of Public Health in Baltimore. "(This) constant high-level 
exposure of microorganisms to antimicrobials contained in the sludge and 
sludge-amended soils may give rise to drug-resistant bacteria and pathogens, 
also known as `superbugs.'"

A study released in May 2006 by Halden and his colleagues found that 76 
percent of a commonly used antimicrobial agent, triclocarban, which is used 
in personal care products such as hand soaps, is released into farms that 
use biosolid sludge from treatment plants as fertilizer.

The Johns Hopkins team found that personal care manufacturers add from 
500,000 to 1 million pounds of triclocarban to their products each year. In 
addition to the resistance these products might contribute to, these 
chemicals have also been linked to decreases in birth weight.

As the amount of antimicrobial agents and antibiotic medicines being 
released into the environment increases, the chance for bacteria to develop 
resistance also increases, Halden said.

"A transformation of antibiotic-sensitive pathogens to drug-resistant 
`superbugs' is of concern as it may increase mortality in infected 
individuals," he said. "Also, non-pathogenic bacteria may acquire drug 
resistance and pass this trait on to human pathogens (already) present in 
the environment."

The problem of resistant bacteria has become extensive, said Fred Tenover, 
associate director for laboratory science in the division of health care 
quality promotion at the Federal Centers for Disease Control and Prevention.

"Depending on the organism and drug combination you're looking at, 
(resistance) has become very widespread," said Tenover, noting that 90 
percent of all staph infections are resistant to medicine that was once 
used. "Penicillin just simply does not work on these organisms anymore.

"And this is not just a United States problem - it's a global problem," he 
added.

http://www.contracostatimes.com/mld/cctimes/news/nation/15574752.htm