Message in a bottle could save lives in the Third World

The device is the brainchild of Northumbria University PhD student Puja Tandon.

The bottle is fitted with a special chemical system that alerts people when sewage bacteria such as E. coli are present in drinking water. Such bacteria indicate the risk of water-borne diseases such as diarrhoea, which still kills several million children under-five in developing countries every year.

The bottle contains a dried mixture of all of the nutrients required to help these bacteria grow – under conditions similar to those in the human gut – along with a chemical indicator that changes colour (to black) if E. coli is present. A sample of water is taken directly into the bottle and then placed in a dark room overnight. The next day if the water has turned black, it means that it is contaminated and should not be drunk without treatment.

Puja says: “If the water is black then there are simple methods of killing the bacteria. People can either leave it in a clear bottle in direct sunlight for five to six hours and the sunlight will kill the organisms, or they can store the water in copper vessels for 48 hours which effectively sanitises the water. Boiling is another alternative, but only where there is sufficient fuelwood.’’

As part of her research Puja has also discovered that when water is stored in brass, minute traces of copper dissolve in the water, inactivating bacteria such as E. coli in 24-48 hours. The amounts of copper are too small to be toxic to people but they are sufficient to kill the bacteria.

Puja adds: “The problem previously was that people had no way of knowing if their water was safe or not and were playing ‘Russian roulette’ with their lives.’’

Puja, 27, from Punjab in northern India, has spent the last three and a half years researching her subject. She spent nine months each year testing water supplies in the Microbiology Department of Panjab University and the other three months working under the supervision of Professor Rob Reed at Northumbria University in Newcastle.

She calls her device the “coliblack’’ system, after the bacteria it detects and the colour the water becomes when contaminated.

She is now working as a biotechnology lecturer as well as an international co-ordinator at a University in India. However, she hopes to secure additional funding which would allow her to carry out post-doctoral study at Northumbria University and extend her current research.

She adds: “It gives me great satisfaction to know that this work will benefit my fellow countrymen and prevent ill health. I’m hoping to continue my studies as a postdoctoral researcher and then finally to work in India where I can put my knowledge and skills to good use.’’

At the moment she is looking for a cheaper chemical ingredient to use in the system, so that the device can be made affordable for everyone in the Third World.

Professor Rob Reed said: “Puja has been an exemplary student, and her work offers real promise to those in rural India and other developing countries who are at greatest risk from waterborne disease”.

Puja will receive her PhD from Northumbria University at an awards ceremony on Thursday, 20 July.