by Mari Jensen, UA News Services
June 2, 2005
The detection, remediation and prevention of water contamination in the Southwest and its human health effects will be a major thrust of The University of Arizona's Superfund Basic Research Program (SBRP) in the next five years. Another aspect of the program will investigate ways to reduce airborne contamination from abandoned mine tailings. (http://superfund.pharmacy.arizona.edu/)
Nine research projects will focus on two major types of contaminants: arsenic, a naturally occurring contaminant in surface and ground waters throughout the West, and halogenated organic solvents such as TCE, or trichloroethylene. Five of the projects will examine the human health effects of the contaminants and four will develop better ways to detect and clean up contaminated sites.
"We are recognized nationally for our research on both TCE and arsenic contamination and their associated health effects," said A. Jay Gandolfi, a UA professor of pharmacology and toxicology and director of UA's SBRP. The program involves about 70 researchers and spans five UA colleges and 10 departments.
Previous environmental studies done by UA's SBRP, which began in 1989, developed technology to detect and clean up contaminants. It's time for the next step, Gandolfi said. "Now we're ready to take the technology from the lab and hone it so it can be applied to these problems."
The earlier research is also starting to pay off in term of treating the health effects of contaminants, he said. "Now our work is aimed at applying biomarkers to identify susceptible people and propose potential treatments."
A. Jay Gandolfi standing next an instrument used in his laboratory to perform metal analyses for UA's Superfund projects. Photo credit: Margaret Hartshorn, UA.
- Updated: June 25, 2005
The new projects, funded by a recent five-year $14 million grant renewal from the National Institute of Environmental Health Sciences, will improve hazardous waste management in Arizona and the Southwest and can serve as a model for arid and semi-arid regions the world.
Removing arsenic from drinking water is a new challenge facing water utilities throughout the West because the Environmental Protection Agency has reduced the acceptable levels of the contaminant. Arsenic has been implicated in skin and bladder cancer, vascular disease, heart defects in newborns and diabetes.
Arsenic can be filtered out of water. However, used arsenic-laden filters pose a waste disposal problem. If such filters are dumped in a landfill, the microorganisms in the landfill free the arsenic from the filters. The contaminant can then percolate down through the soil and eventually enter the groundwater.
SBRP researchers want to develop better ways to remove arsenic from drinking water and to dispose of the arsenic residues. "We want to help prevent another hazardous waste problem from developing 10-15 years from now," said Raina M. Maier, the SBRP's associate director and a UA professor of soil, water and environmental science.
Another problem throughout the West is water and air contamination from abandoned mine tailings, the piles of rubble and processed ore that remain at mining sites. Arsenic and lead are found in high concentrations in tailings piles. Arizona alone has about 80,000 inactive and abandoned mining sites covering more than 130,000 acres (200 square miles).
Maier said, "Some piles are so toxic and the material is so unlike soil that nothing grows there. The piles are subject to wind and water erosion." SBRP researchers are working on easy, low-cost ways to revegetate tailings piles with native plants. The scientists will search for ways to reduce or eliminate the need for site preparation, fertilizer or maintenance.
"Microbes can make plant hormones, bind toxic metals and help condition sites," said Maier, who is an environmental microbiologist. "My hope and dream is that we would be able to soak the seeds in a microbial inoculum, then plant them and walk away."
Because contaminant removal can't happen overnight, half the SBRP research projects are dedicated to elucidating the health effects of TCE and arsenic. SBRP scientists have already shown that exposure to TCE may cause heart defects in newborn children. Now the researchers are determining exactly how TCE causes such damage, with the hope of preventing the damage to future generations.
The scientists also are investigating how people of particular ages or ethnicities differ in their susceptibility to the contaminants' toxic effects. Another aspect of the research will figure out how arsenic affects the vascular system and the lungs and how arsenic causes bladder cancer.
Maier stresses that solving these problems, which are not limited to Arizona, can benefit people throughout the world. The SBRP has an active outreach program to train Mexican scientists and practitioners in the detection and remediation methods UA scientists are developing. "We are sharing with our neighbor with whom we share a border -- a very polluted border, I may add."