AMHERST, Mass. - More than 80 percent of the world's population depends on rice as a staple food, but production is dropping in the rice paddies of Bangladesh, parts of India and South and East Asia due to toxic levels of arsenic in the topsoil.

Om Parkash of the University of Massachusetts Amherst leads a research team that uses genetic engineering to produce rice plants that block the uptake of arsenic, which could increase production of this valuable crop and provide safer food supplies for millions.

"By increasing the activity of certain genes, we can create strains of rice that are highly resistant to arsenic and other toxic metals," says Parkash, a professor of plant, soil and insect sciences. "Rice plants modified in this way accumulate several-fold more biomass, and less arsenic, in their above-ground tissues, making the rice safer to eat and more productive." This could help alleviate the current world-wide rice shortage.

Deep tube wells installed to provide drinking water in Bangladesh and other countries are producing water with naturally occurring levels of arsenic that greatly exceed safe limits in drinking water. Groundwater is then being used to irrigate rice paddies, and this irrigation is causing a buildup of arsenic in topsoils that is toxic to the rice plants, reducing the amount of rice that can be produced in a given area.

According to Parkash, arsenic builds up in all parts of the plant, including the rice grains used for food, creating health problems in hundreds of thousands of people, including several forms of cancer. Arsenic is also present in the rice straw used as animal fodder, causing arsenic to enter the food chain in dairy products and meat, and affecting the health of animals.

"Already on the Indian subcontinent, particularly in Bangladesh and West Bengal, there are more than 300,000 people who have developed cancer from arsenic poisoning by drinking contaminated water and eating contaminated food," says Parkash. "The World Health Organization has dubbed this one of the major environmental disasters in human history."

Parkash is currently working with the UMass Amherst Office of Commercial Ventures and Intellectual Property and several interested companies to bring this technology to the marketplace. "Basically, the companies will use our gene constructs in new or existing rice lines, producing hybrid rice that will go through the cultivation and seed production stage," says Parkash. "Then the new strains of rice will be commercialized and brought to market."

Parkash's research is funded through the Massachusetts Technology Transfer Center from the Office of the President of the University of Massachusetts. A podcast featuring research by Parkash can be found at www.umasstechcast.org.