Global health experts

Carbon nanotubes could replace the conventional materials used in water purification systemsRESEARCHERS in India claim nanotechnology could be used to ensure a safe supply of drinking water for regions stricken by drought or contamination.
The team, from the Bhabha Atomic Research Centre (BARC) in Mumbai, India, says carbon nanotubes could replace the conventional materials used in water purification systems.
The nanotubes are hollow carbon fibres which are over a billion times thinner than a single human hair. The chemical properties of carbon allow only small molecules, such as water, to pass along its interior. The researchers claim viruses, bacteria, toxic metal ions and noxious organic materials are too large to pass over the fibres.
According to the scientists, using the nanotubes to replace existing filter technology, such as membranes, would produce higher flowrates and reduce power requirements. The systems could also be inexpensively installed, operated and maintained.
Global health experts say over one billion people currenlty lack access to safe drinking water and 2.4b people lack access to proper sanitation, nearly all of them in developing countries. At present, one third of the world's population live in water-stressed countries. This is expected to rise to two thirds by 2025.