Scientist's bright idea cleans up

Dr Reed discovered oxygen could help purify water

A British scientist is working to bring cleaner drinking water to millions of people living in the third-world.

Microbiologist Dr Rob Reed has discovered how to decontaminate drinking water using just oxygen and sunlight.

The University of Northumbria lecturer has now received a grant to carry out pilot trials in India and could provide cleaner drinking water for millions.

Of the millions of people who die every year of water-related deaths, about 90% are caused by contamination - causing diseases such as dysentery - and not shortages.

About 3.5m children die every year from water-related diseases so it is a massive problem

Dr Rob Reed

Previous research into the use of sunlight have proved inconclusive but Dr Reed realised the key ingredient could be oxygen.

Dr Reed told BBC News Online: "Originally we were doing some research into sewage in sea water and found the way to kill bacteria like e-coli was UV light and oxygen.

"I had a sudden eureka moment and realised we could do this with drinking water.

"I discovered that there were mixed conclusions about treating water with just sunlight and I realised that oxygen could be the answer.

"Bacteria in water treated with sunlight decreases 10 times more slowly than aerated water."

Dr Reed discovered that aerating contaminated water before and during exposure to sunlight ensures that the bacteria are killed off every time.

Pilot studies will take place in Rajasthan

Now the lecturer is taking part in a collaborative research project with a university in India exploring the use of sunlight to decontaminate water.

Working in partnership with Dr Isaac Bright Singh of Cochin University in Kerala, he is conducting an in-depth study, funded by the Wellcome Trust.

"We first teamed up a couple of years ago and now those links have been made more formal," added Dr Reed.

"There is enough funding for three years of tests."

Pilot studies will be undertaken in the arid region of Rajasthan, the flood-prone Uttar-Pradesh and the humid area of Kerala, to see the effectiveness of the method under a range of conditions.

Water in two types of plastic container will be tested for bacteria both before and after exposure to sunlight.

Huge impact

Dr Reed said the cheap method of purifying water could have a huge impact..

"If you have any other alternative you would not choose to drink this water," he said.

"But we are talking about people who would walk into a puddle and drink it straight down.

"About 3.5m children die every year from water-related diseases so it is a massive problem.

"This method of purification is better than nothing, and although it doesn't work against viruses, it can kill bacteria, it is cheap, and all people need is to know how to do it."

Dr Reed said through his research he discovered a similar process was popular in India about 2,000 years ago.

He said: "Sunlight was used as a traditional means of purifying water in India in ancient times.

"People used to leave water in sunlight, pray to the water, leave it all day and then drink the purified water at the end of the day. It seems likely that it was the sunshine that did the purifying, not the prayer!"