Abul Hussam, associate professor of chemistry and biochemistry at George Mason University, Virginia, USA, and Dr AKM Munir, a physician from Kushtia, innovated the technology.

NEA President Wm A Wulf officially declared Sono Filter as the winner of "The Grainger Challenge Prize for Sustainability" at Washington yesterday. The prize-giving ceremony will take place on February 20 at the NAE Complex Washington.

Hussam and Munir started experimenting on the Sono Filter around seven years back and Kushtia-based NGO Manab Shakti Unnayan Kendro has been distributing the filters in arsenic affected areas at the upazila level since 2004.

The NAE introduced the one million dollar award in January 2005 for innovating a sustainable, cost-effective and socially accepted technology as the technologies available for removing arsenic from contaminated water were not beyond questions.

The goal of the Grainger Challenge Prize is to encourage the innovation of household or community-scale water treatment system to remove arsenic from the contaminated groundwater. The system must have a low life-cycle cost and must be robust, reliable, easily maintainable, socially acceptable, and affordable, said a press release. As a sustainable technology, the system must also be within the manufacturing capabilities of a developing country and must not degrade other water quality characteristics and to promote green design philosophies.

The Sono Filter was one of the 15 technologies out of more than 100 entries selected to compete in the final/testing stage of the challenge which began in early July 2006. The total testing and technology evaluation procedure was conducted by United States Environmental Protection Agencies (US-EPA) testing and evaluation facilities at Cincinnati, Ohio and reviewed by a panel of 10-member reviewers committee.