Copenhagen, Denmark — Hard work, bleeding-edge innovation and hope are driving the fledgling products and services of nanotechnology — science on the scale of atoms and molecules — along a pipeline that starts in the research laboratory and ends in a range of improved applications.

Nanoscale materials, coatings, membranes, catalysts and other technologies are being developed for use in electronics, energy production and storage, information technology, medicine and health — but industry and consumers will not be the only beneficiaries of these advances.

At Nanotech Northern Europe 2008, held September 23-25 in Copenhagen for 800 participants from 44 countries, a group of international policymakers and experts examined the potential of nanotechnology to help 1.1 billion people who lack access to clean water and 2.5 billion — 42 percent of the global population — who lack access to basic sanitation like toilets and safe latrines. (See “Nations Worldwide Pour Billions into Nanotechnology.”)

“Water purification and desalination has been done in pretty much the same way for decades, said Robert Rudnitsky, a physicist at the U.S. State Department and chair of the Organisation for Economic Co-operation and Development (OECD) Working Party on Nanotechnology. “What we are seeing is that nanotechnology is likely to bring about improvements to existing methods and create entirely new approaches.”

The Working Party on Nanotechnology sponsored the water session at Nanotech Northern Europe as part of its project on using nanotechnology to address global challenges.

According to the World Health Organization/UNICEF Joint Monitoring Programme for Water Supply and Sanitation, diarrheal disease, which could be prevented by better management of drinking water and sanitation, caused more deaths in 2004 than did HIV/AIDS.

Nanoscience describes the ability to see, measure, manipulate and manufacture things on a scale of 1 to 100 nanometers. A nanometer is 1 billionth of a meter; a sheet of paper is about 100,000 nanometers thick. At this scale, the physical, chemical and biological properties of materials differ in basic ways from the properties of individual atoms and molecules or bulk matter.

SMALLER IS BETTER

One way nanotechnology can minimize the world’s water and sanitation problems is by changing how clean water is delivered to those who need it.

Developed nations use large centralized water collection, chemical treatment and distribution systems whose thousands of kilometers of pipes deliver water to homes and businesses, said Mark Shannon, a professor of mechanical engineering at the University of Illinois-Urbana-Champaign and director of the Center of Advanced Materials for the Purification of Water with Systems (WaterCAMPWS), funded by the U.S. National Science Foundation.

“Centralized systems are capital intensive, energy intensive and chemically intensive,” he said. “Five out of six people on Earth can’t use the systems we’re currently using. There’s not enough money or time to replicate this system around the world.”

In the developing world, nanotechnology can contribute to smaller, distributed systems that incorporate materials and systems for removing contaminants and pathogens, including viruses — which at 5 to 300 nanometers in length are themselves at the nanoscale — without the use of chemicals. Viruses are difficult to eliminate from drinking water using current methods, even in developed countries.

“We have people working on developing what would be a litmus paper,” Shannon said, “that people could dip into the water and it would change color if mercury or lead were present. Now we’re working on [detecting] viruses with the same type of technology.”

NANOTECHNOLOGY AT WORK

Nanotechnology is at work in the villages of Obambo and Kadenge in western Kenya, for example, where Sky Hydrants developed by Siemens AG turn brown sludge from the local dam into clear drinking water.

The self-cleaning ultrafiltration device consists of three piano-sized cartridges that each contains 10,000 minipipes made from thin membranes whose 100-nanometer-diameter openings keep dirt and bacteria from passing through.

Another effort, solar disinfection of drinking water (SODISWATER) is a research project funded by the European Union to show that solar disinfection of drinking water is effective against a range of waterborne diarrheal diseases like cholera at the household level and as emergency relief after natural or other disasters.

Solar disinfection works by filling transparent bottles with contaminated water and placing them in direct sunlight. The water is safer to drink after six hours because the sun’s ultraviolet (UV) radiation kills bacteria. More than 2 million people in 28 countries use the technique.

Tony Byrne, lecturer at the University of Ulster Nanotechnology and Integrated BioEngineering Centre in Ireland, one of the project partners, is part of a technical group that is exploring the use of nanotechnology to enhance the SODIS UV pathogen-killing process and determine if the SODIS process fails to kill any important waterborne diseases.

But one of nanotechnology’s greatest potential benefits might lie in advanced filtration and biological systems that are in development to turn saltwater into freshwater and wastewater into a resource, Shannon said.

“We need to stop thinking about wastewater as a waste and start thinking about it as a resource,” he added.

More information about the WaterCAMPWS is available on the organization’s Web site.

More information about the EU-funded SODISWATER Research Program is available on the iniative’s Web site.