This report, written for the Meridian Institute by a team of scientists from South Africa and Sri Lanka, describes the general issues facing projects aimed at improving access to clean water in the developing world, as well as the specific challenges facing nano-based projects.

The authors describe a number of water treatment devices that incorporate nanotechnology, including nanofiltration membranes, attapulgite clays and zeolites, nanocatalysts, magnetic nanoparticles and nanosensors. More importantly, they outline potential opportunities associated with these technologies, and possible risks.

The paper includes two case studies of projects designed to improve access to clean water — one in Bangladesh based on a conventional approach using sari cloth to remove cholera from water, and one in South Africa that incorporates a nanofiltration membrane.