Scientists noticed that old, dirty water filters seemed to make water taste better. They investigated this peculiarity, and found that tiny bacteria that thrive on dirty water filters can reduce the distasteful earthy tinge in tap water.
In a recent study, the scientists found that bacteria that grow on particles in a sand filter effectively extract the compounds that produce the bad taste. The researchers are from the Australian Water Quality Center and The University of Adelaide.
The team explained that sand filters can extract from water some common earthy molecules, such as geosmin and methylisoborneol, which are compounds that occur naturally in water. These earthy compounds are not easily removed by conventional methods, but old filters contain particles of sand that accumulate in a biological film of bacteria that absorbs and breaks down the biodegradable odor molecules.
The group found that a 26-year-old water filter that possessed a sand biofilm was able to remove significantly more of the earthy molecules than newer water filters.
Although the natural earthy and musty smells in tap water are not usually a health risk, many consumers prefer a fresher taste, and water companies may be able to use sand biofilms from old water filters to make water taste pure and fresh.
via: Innovations Report