Naturally high levels of dissolved metals in groundwater pollute millions of private wells in Bangladesh, affecting tens of millions in what has been recognized as history's most widespread environmental contamination. Dr. Xiaoguang Meng, Professor of Environmental Engineering at Stevens Institute of Technology, recently returned from a month-long mission to Bangladesh where he and his associates field tested experimental filtration methods that will help UNICEF design small community water treatment systems for removal of manganese and iron in well water.
Dr. Meng specializes in water treatment technologies that blend cutting-edge research with affordable, easy-to-use techniques. Since the 1990s, he and other researchers with Stevens Center for Environmental Systems have been working in the Southeast Asian country to battle troublesome contaminants, especially highly toxic arsenic, in groundwater.
In his latest research trip, Dr. Meng focused on filtration methods targeting manganese and iron. While these are necessary nutrients in moderation, at high levels they give water an unpleasant flavor and color, leave sediment in cups and basins, and are associated with various health risks. Excessive manganese has been shown to cause neurological damage, especially in developing children. High levels of iron can support the growth of bacteria that foul drinking water and cause deadly diarrheal disease, which also disproportionately affects young children. Where arsenic is present, the toxic chemical will bond with ferric compounds, making iron removal a key ingredient in fighting arsenic contamination.
In addition to his metals filtration research, Dr. Meng is also conducting an ongoing study of a household chlorination/dechlorination water container that he developed to improve adoption of water disinfection treatments. Chlorination is an important method in developing countries like Bangladesh, as it helps prevent bacterial and viral pathogen transmission through contaminated drinking water and food, the main causes of diarrheal disease.
According to the World Health Organization, diarrheal disease is responsible for the deaths of 1.8 million people worldwide every year and is the second leading cause of death in children under five years old. In Bangladesh, which has the second highest under-five mortality rate in Southeast Asia, diarrhea is one of the leading causes of death in children under five, accounting for 11 percent of all child deaths.
Although chlorination is widely available as a water treatment, adopting this method can meet unfortunate resistance due to the undesirable taste and smell of residual chlorine. To combat the current perception of chlorinated water, Dr. Meng has introduced an activated carbon filter that effectively removes chlorine taste and smell from disinfected water. By displaying these units in targeted areas of Bangladesh, Dr. Meng is improving public acceptance of disinfected drinking water.
Dr. Meng began traveling to Bangladesh to demonstrate how his developments from the lab interact with the unique water chemistries found in some of the world's most polluted areas. During his first expedition, in 1999, he proved a coprecipitation-filtration technique for treatment of arsenic. The filtration system requires only a plastic bucket, sand and a disposable packet of chemicals. The entire unit costs a family $5 or less per year to use.
For students at Stevens, Dr. Meng's work has meant incredible mentoring opportunities through participation in research with global impact. He has seen nearly 30 of his projects funded, most of them in the pursuit of purifying water, and has co-authored four patents. After raising more than $1 million in venture funding, HydroGlobe, a company co-founded by Dr. Meng to manufacture a patented water purification system, was profitably acquired by Graver Technologies.
"Scientists and engineers play a critical role in addressing environmental issues that have impact on people's lives and especially in creating technological solutions that can be cost effective to the stakeholders if they are to be adopted," explains Dr. Keith Sheppard, Associate Dean of the Schaefer School of Engineering and Science. "Stevens actively promotes high-tech stewardship through supporting sustainability research and educational opportunities for our students."
If you want to affect real change throughout the world, learn about research and educational programs at Stevens by visiting the websites for the Department of Civil, Environmental and Ocean Engineering or [email protected].