Faster Water Quality Test Coming Soon

E coli levels in water may soon be tested with quick and easy paper strips

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Summertime is just around the corner, and dog days at the beach may be part of many families' vacation plans. But parents may be wondering about how clean the water is.

Water-testing technology so far has been inadequate in testing for bacteria because it's not accessible enough to check all swimming spots or it can't keep up with quickly changing conditions at some sites.

Now a new, faster method for testing may be available from researchers whose paper strip method can detect E. coli in minutes.

"Check for safe and clear beaches ahead of time."

Lead author John Brennan, a chemistry professor at McMaster University in Ontario, Canada, and colleagues from the Sentinel Bioactive Paper Network have developed a test paper strip that can detect high levels of E. coli in water with better accuracy than the portable technology currently available.

The paper strips are coated with chemicals that react to the bacteria within 30 minutes of sampling by turning a different color. The color depends on what forms of E. coli are present and in what concentrations.

The strips can be printed with the chemicals using inkjet technology, so they may become available for the general public to test water easily. The researchers estimate a commercial test strip being available in about two to three years.

Because the technology is not available on the market yet, no price has been attached to it, but the researchers spoke of it as an inexpensive option for water testing.

"One of the problems right now is that there is no simple, fast and cheap way to test recreational water, and certainly nothing out there in the realm of rapid tests for drinking water," Brennan said.

They are testing prototypes of the strips in Canada and other parts of the world where there is likely to be unhealthy or unsafe water so that they can refine the strips.

The limit for safe swimming is typically no more than 100 to 500 bacterial cells per 100 mL of water, depending on the location.

Although a long way off, the researchers hope the strips may be eventually developed to a sensitivity level strong enough to detect whether water is safe to drink.

The research appeared online April 30 in the journal Analytical and Bioanalytical Chemistry. The research was funded by the Natural Sciences and Engineering Research Council of Canada and the Sentinel-Canadian Network for the Development and Use of Bioactive Paper.

The next phase of development of the strips is being funded by an NSERC Phase I Ideas to Innovation grant. No conflicts of interest were noted.

Reviewed by: 
Review Date: 
May 2, 2012
Last Updated:
May 9, 2012