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Where taste buds fail, nuclear technology succeeds in UN water age test

Where taste buds fail, nuclear technology succeeds in UN water age test

As far as water vintage goes, age makes no difference, according to a "taste test" exhibit at the United Nations nuclear watchdog's General Conference in Vienna today. But what the taste buds fail to pick up on, nuclear technology discerns, helping countries to better manage their freshwater sources.

At the International Atomic Energy Agency (IAEA) exhibit, three glasses from around the world sat on a table waiting for the water experts. They looked identical and smelled alike, and all originated from local rain. But one was five-year-old tap water from Vienna, another a 25,000-year-old sample the Kufra aquifer in Libya, and the third 140,000-year-old rain from the Great Artesian Basin in Australia.

But the experts were fooled, finding no gustatory clue to betray which was which, even if the Aussie water perhaps tasted a little saltier. But age-revealing chemical isotopes are eminently transparent to nuclear technology and that is where countries can benefit.

The younger the water is, the more communities can pump away with the confidence that rainfall is replenishing their water supply, but ancient waters are limited resources. By knowing the age countries can better sustain their freshwater sources.

Scientists are sharing vital information through IAEA-supported projects around the world. If you look at the Middle East, everywhere you are using old water, said Pradeep Aggarwal, who heads the IAEA isotope hydrology unit.

"It is rainfall from 10,000, maybe 100,000 years ago. So countries have to understand there's a limit to how long this will last," he added.

The natural isotopes of water are studied using techniques collectively known as isotope hydrology. Cheap and reliable, they tell scientists how much water is available, how often it is replenished, where it comes from and if there is any more to be found.

"Isotope hydrology offers a way to better manage the planets water resources and help prevent future crisis," IAEA said.