Arsenic-free water

Rice University researchers are to conduct the first field tests of 'nanorust', a technology for removing arsenic from drinking water, later this year in Guanajuato, Mexico.

The arsenic-removing technology is based on the unique properties of particles called 'nanorust', tiny bits of iron oxide smaller than living cells.

The nanorust naturally binds with arsenic and can be used as an inexpensive way of removing arsenic from water.

'Mexico is debating the adoption of more stringent national standards for allowable levels of arsenic in drinking water, and officials in Guanajuato are looking ahead to explore ways they might meet stricter new standards,' said nanorust inventor Vicki Colvin, Rice's Pitzer-Schlumberger Professor of Chemistry and director of Rice's Center for Biological and Environmental Nanotechnology (CBEN).

Qilin Li, assistant professor of civil and environmental engineering and a CBEN faculty expert in water treatment, said that the Rice team plans to test nanorust-coated sand.

The material will be used in sand filters to treat groundwater from wells.

The water treated with nanorust will be kept separate from the water that is released for human consumption.

Pedro Alvarez, the George R Brown Professor of Engineering and chair of the Department of Civil and Environmental Engineering, said that one other benefit of the nanorust filters is that they may help remove waterborne viruses responsible for a wide variety of gastrointestinal diseases.

Arsenic is a colourless, odourless, tasteless element, and prolonged exposure to dangerous levels of arsenic can lead to skin discoloration, sickness and cancer.

Arsenic-poisoned drinking water is a global problem, affecting tens of millions of people in communities in Asia, Africa, North America, South America and Europe.