Study finds whisky residue purifies poison water

An academic looking at uses for whisky by-product has inadvertently discovered how to purify poisoned water in Bangladesh.

An academic from Aberdeen University inadvertently discovered that whisky residue could purify water poisoned by arsenic

Dr Leigh Cassidy, who is currently working on her Phd at Aberdeen University, discovered a way to use ‘draff’ – a barley husk residue that is left after whisky distillation – as a cleansing agent for water.

By modifying the draff with a “secret ingredient”, Cassidy created ‘Dram’, which stands for ‘device for the remediation and attenuation of multiple pollutants’.

This device has now been modified to treat water poisoned by arsenic in Bangladesh by using coconut shells or rice husks to filter and trap the arsenic.

It pumps water into the bottom of a stainless steel tubewell, filtering it through an organic filter which binds the arsenic. Clean water is then pumped out of the top of the unit.

Toronto-based charity PurifAid is using a £60,000 grant from Grand Challenges Canada to launch the project in Bangladesh.

Shahreen Reza, founder of PuriAid, told the Guardian that she favours the Dram device for its simplicity and because requires no change in behaviour from villagers.

“The water is decontaminated at a rate of 1,000 litres an hour, which is at industrial levels,” she said.

“The filter, which must be replaced every four to six months, can be used as biofuel and the units only need a simple cleaning every four to five months.”

A business model to help local villagers use the Dram is currently being developed.

The arsenic crisis in Bangladesh is considered to be one of the worst cases of mass poisoning in history, with one in five deaths in the country attributed to contaminated drinking water.