Schematic diagram of SONO filter (Source: Hussam and Munir (2007))
The supply of pure drinking water from groundwater sources to at least 97 percent of the population has been one of the few success stories in public health care in Bangladesh. Groundwater appeared to be a viable alternative to the bacteriologically-contaminated surface water, which caused hundreds of thousands of deaths. The success, however, was compromised in the early 1990’s by reports of unsafe arsenic levels found in the groundwater extracted by tubewells (a kind of manual water pump) in many parts of the country. Arsenic – the new menace – shattered the notion of tubewell water as “safe.” Indeed, the toxic effects of arsenic in drinking water has also been a health hazard to millions of people in other countries, including Cambodia, India, Nepal, Vietnam and even the United States.
The extent and severity of the problem is particularly heavy in Bangladesh: out of 64 districts, water in 61 districts has arsenic concentration above the safe limit and up to 77 million people have been exposed to “arsenicosis” – a disease caused by chronic arsenic poisoning. Efforts by the government and non-government organizations (NGO) to mitigate arsenic contamination have faced the challenges of developing a cost-efficient method for offering arsenic-free and safe drinking water. A major breakthrough came when Dr. Abul Hussam, a Bangladeshi chemist based at George Mason University in the United States, developed a simple and effective filter to remove arsenic from water in 2001. It is estimated that by 2010, as many as 1 million people in Bangladesh have been benefitting from Dr. Hussam’s “SONO” filtration system.
After graduating in chemistry from the University of Dhaka, Bangladesh, Dr. Hussam went to the University of Pittsburgh in the United States in 1978 to earn his Ph.D. in analytical chemistry. He later joined George Mason University (GMU), where he still teaches chemistry. At Pittsburgh, he learnt about the use of computer controlled electrochemical methods for analyzing water toxicity. When the arsenic problem emerged in Bangladesh during the 1990s, Dr. Hussam realized that a precise method for detecting traces of arsenic was the first step in any mitigation procedure. With the help of his physician brother, he established a test lab in his native district of Kushtia, a heavy arsenic-affected region in Bangladesh. The lab was equipped with a computer controlled analyzer for detecting arsenic in water.
Once the lab was ready, Dr. Hussam began testing water from different tubewells in the region. His background in analytical chemistry enabled him to develop an economical and affordable filtration system to remove arsenic particles from water. The first functioning filter was developed in 1999, but he kept on researching to further improve the system. It took him two more years to decide that the filter was finally ready for public use. The mechanism of the filter is simple yet very effective; it is a two-step filtration system using a composite iron matrix invented by Dr. Hussam, wood charcoal, river sand, and brick chips. The first step removes arsenic and the second one removes other contaminants as well as fine particles. He named it the “SONO” filter. It is a completely non-chemical filtration system and does not require any pre-treatment of water.
Certain questions have been raised relating to the management of the residual waste from the SONO filters. However, results of the tests conducted using contemporary techniques show that the residue created by SONO is non-toxic and harmless. The National Academy of Engineering (NAE) of the United States examined SONO’s residual composite iron matrix and found it to be non-hazardous. The filtration system has been approved by the World Health Organization (WHO), the government of Bangladesh and the local bureau of Isotope Hydrology Section of the International Atomic Energy Agency (IAEA).
"If your innovation does not improve the lives of others, it is useless innovation", says Dr. Munir.
The SONO filtration system is suitable for rural use for a variety of reasons. It outperforms some of the previous arsenic removal techniques in the sense that it does not require any energy input, it is reliable, and it can be produced and maintained at a very low cost with locally available materials. A SONO filter costs about US$35, can produce 20 to 50 liters of clean water per hour, and is guaranteed to have a five-year life span, although Dr. Hussam believes that the filter is likely to remain functional many years beyond the guarantee period. One filter can provide enough pure water for one or two families.
The SONO filter is patented as the “Arsenic Removal Filter” (Patent No. 1003935, 2002) with the Department of Patents, Design and Trade Marks of Bangladesh. Two international patent applications for the combination of active materials in the system have been made under the Patent Cooperation Treaty (PCT), and a patent in the United States is pending as of 2010.
The filter was developed in close cooperation with the Department of Chemistry and Biochemistry of GMU. In order to enable Dr. Hussam to further develop and disseminate sustainable technologies for clean water, GMU has established a Center for Clean Water and Sustainable Technologies (CCWST). Dr. Hussam is also working in collaboration with the University of Maryland and the Swiss Federal Institute of Aquatic Science and Technology.
Following the successful development of the SONO filter and approval from governing authorities, commercial production of the filter has been initiated by Manob Sakti Unnayan Kendro (MSUK), a non-governmental organization (NGO) run by Dr. Hussam’s brother. The original arsenic testing lab has been converted into SONO Diagnostic Inc., which now supervises the manufacturing of the filters. MSUK received financial support from the Federal Ministry of Economic Cooperation and Development, Germany. As of 2010, the NGO has produced about 160,000 SONO filters which are being used in Bangladesh, India and Nepal. Thousands of these filters have been donated in many districts in Bangladesh. MSUK also provides training on the use of the SONO filter at home and free health care service for arsenicosis patients. Some other Bangladeshi NGOs are also working to install SONO filters.
Along with household installations, SONO filters are now operational in many social institutions; primary and secondary schools, villages, restaurants and cafes. Due to its low cost and easy maintenance, SONO has become an affordable technology for Bangladesh.
The SONO filter has had important positive effects in preventing health problems in hundreds of thousands of people in Bangladesh. According to Dr. Hussam, “Patients drinking the filtered water for two years show arsenical melanosis [skin pigment changes] disappeared with significant improvement in their health”. Additionally, there are no new cases of arsenicosis among the people drinking the filtered water. As many as one million people are believed to have benefitting from the SONO filter as of 2010, with new filters continuously being installed. Professor Johannes Coetzee, Dr. Hussam’s Ph.D. supervisor, believes that the SONO filter is “a major contribution to science and to the welfare of Bangladeshis. He [Dr. Hussam] applied the knowledge from his doctoral studies to a practical matter of great importance”.
Dr. Hussam also won the Grainger Challenge Prize of US$1 million in 2007 for his unique invention. The Prize was created by the NAE in 2005 with support from the Grainger Foundation. The NAE initiated an open competition for the American engineering community to develop a water treatment system that would significantly lower the arsenic content in groundwater from tube wells in developing countries. The challenge stipulated that the winning system should be low-cost, technically robust, reliable and maintainable; be socially acceptable and affordable; be manufacturable and serviceable in a developing country; and not degrade other water quality characteristics or create a toxic waste disposal hazard. Dr. Hussam has donated most of the million dollar prize for further development and distribution of the filters. The same year, he was also named one of Time Magazine’s Heroes of the Environment. In 2008 Dr. Hussam received an “Outstanding American by Choice” certificate from the United States Citizenship and Immigration Services (USCIS).
The filter’s success has prompted other countries with arsenic contamination to contact Dr. Hussam for its potential use. India and Nepal are already using the filter, while communications have been made with the United States, China, and several countries in Central and South America. Arsenic mitigation groups from Nigeria and South Africa have contacted Dr. Hussam through the United Nations Children’s Fund (UNICEF).
“The lack of clean water affects millions of people, with illness and lost educational opportunities in childhood, leading to poverty in adulthood, and solving this problem can bring a significant dividend for all in terms of better living”- is the belief that led Dr. Hussam to use his knowledge to bring about a solution against the arsenic menace. His social commitment has also brought him business success and fame, but nonetheless he remains committed to further his research works in the area of clean water and sustainable technologies for social and human development.
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