Fluoro sensors to pick up contamination in recycled water

London, April 14 (ANI): A team of researchers has said the technology that uses fluorescence sensors to pick up trace sewage contamination may help increase public confidence in recycled water.

"A rapid, highly sensitive and selective detector is urgently required to detect contamination events in recycled water systems," Dr Rita Henderson of the University of New South Wales Water Research Centre told ABC News.

Henderson said that fluorescence spectroscopy may provide the solution because of its high sensitivity.

Fluorescence monitoring is also an attractive approach because it is a rapid technique that requires no sample preparation before analysis, she added.

Fluorescence spectroscopy is now used to monitor the quality of marine water and river ecosystems.

Plant decay products and protein material produced by microbes are known to fluouresce in water.

The fluorescence sensors are able to detect the presence of this organic material, as an indicator of microbial contamination.

According to Henderson, current methods of online water monitoring generally rely on chemical analysis, including assessment of conductivity (salt content), total organic carbon and, in membrane processes, trans-membrane pressure.

However, Henderson says fluorescence can detect changes in water quality that these techniques miss.

She says there is a need for a sensitive technology that provides 24-hour, real-time monitoring of water quality to increase public safety and confidence.

Henderson and colleagues have been looking at the ability of portable fluorescence sensors to detect microbial contamination in dual reticulation systems.

In such systems, both recycled and drinking-quality water are delivered to homes with the recycled water used for flushing toilets and irrigation.

But, evidence shows that recycled water can sometimes be accidentally mixed with drinking water in dual reticulation systems.

Henderson and team are developing a fluorescence sensor that can be held under running water to detect whether drinking water in a dual reticulation system has been compromised.

She says they have been able to detect recycled water at levels as low as 5 percent of the mix.

In the future, fluorescence sensors could be installed in home pipes to monitor the purity of water piped from a recycling plant to dual reticulation systems in homes, according to Henderson.

Sensors could feed back information to the water treatment plant and set off an alarm should any contamination be detected.

Henderson says further research is required to improve the stability of the fluorescent light source used to detect contaminants. (ANI)