Environmental Factor, March 2008, National Institute of Environmental Health Sciences
Superfund Program Helps Train Mexico's Environmental Scientists
By Eddy Ball
Thanks to Hugo Alonso Z����iga HernÁndez - and other young scientists like him - what now looks like a moonscape in the Mexican state of Sonora may one day again live up to the meaning of its name in the Opata language, the "Place of Corn." Z����iga HernÁndez is the latest of 23 bright young exchange students, doctoral candidates and visiting scholars who have returned home to Mexican universities following training in the Mexican Exchange Scientist Program at The University of Arizona's (UA) U.S.-Mexico Binational Center for Environment Sciences and Toxicology, which is part of the Outreach Core funded by the Superfund Basic Research Program (SBRP)(http://www.niehs.nih.gov/research/supported/srp/about/index.cfm).
A student at the Universidad de Sonora (UNISON), Z����iga HernÁndez spent four months as a Training, Internships, Exchanges, and Scholarships (TIES) Fellow in the UA Department of Soil, Water and Environmental Science, studying advanced techniques of phytostabilization for soils around former copper mines in Sonora. Z����iga HernÁndez' field work, which started in February, involves the enrichment of depleted topsoil and the growth of plants to revitalize nutrients and stabilize soils with extensive environmental contaminants.
Mining of copper and other minerals has gone on for centuries in the border state, and resurgence in mining is anticipated due to increased demand and drastically higher prices for the commodity. At arid and semi-arid sites, the materials left over after the process of separating the valuable fraction from the worthless fraction of an ore, known as mine tailings, are prone to wind dispersion and water erosion. According to Z����iga HernÁndez, these pollutants pose a health threat, especially for children in nearby communities and for sensitive riparian or wildlife refuge areas. Successful stabilization of such sites offers an economical approach to containing mining wastes and developing these wastes back into soil-like materials that can support normal vegetation.
Working with the UA team headed by Raina Maier, Ph.D., Z����iga HernÁndez studied methods for the establishment of a vegetation cover using native plants to minimize dispersion and erosion processes. Organic matter amendment up to 15 percent by mass may be required, depending on the extent of pH, metal and microbial community stress that exists in a given site. Successful mine tailings re-vegetation with a goal of minimizing amendment addition will involve tailoring the compost rate to optimize nutrients and microbial supplements and to re-establish the correct pH at a site.
Funded collaboratively by the SBRP, the U.S. Environmental Protection Agency (EPA), which administers a $1.46 million special appropriation from Congress, USAID, and Mexico's Science and Education Ministry (CONACyT), the Binational Center (http://binational.pharmacy.arizona.edu/index.php) is a component of the UA SBRP Outreach Core headed James A. Field, Ph.D., and UA SBRP director A. Jay Gandolfi, Ph.D. A prime example of the NIEHS Strategic Plan goal of developing a global health program, the Binational Center partners with UA scientists from six colleges and Mexican scientists from 11 different universities and research institutes to promote technology and information transfer between the two countries by training the next generation of environmental scientists in the border region.
The Center is also involved in community-based Outreach Projects to educate and empower residents living along the U.S.-Mexico border, which has been impacted with the growth of manufacturing, increase in trade, and rise in populations due to the North American Free Trade Agreement (NAFTA). The Center's goals are to increase public awareness of the risks associated with common occurring contaminants in the Border region, such as arsenic and heavy metals, and to provide information about and assistance with remedial measures.
According to the Center's website, the exchange program is based on a premise of building human capital, as advocated by such social science scholars and economists as the Brazilian Paulo Friere and American Gary Becker. Center literature describes this basis as "an alternative to the old paradigm in which the developed country 'provides solutions' to the emerging country... [a] paradigm that has repeatedly failed and has created a vicious cycle and waste of resources."
The Binational Centers
Trainees' studies in the Mexican Exchange Scientist Program range across the engineering, environmental and biological sciences - including arsenic biotransformation, perchlorate removal and remediation, genetics, environmental toxicology, acid mine drainage, genomic analysis of arsenic and human cells, and characterization of morpho-functional alterations induced by mercuric chloride on a kidney cell line. The trainees typically participate in one of the Center's Collaborative Research Projects.
Center Activities include:
Training Fellowships: Scholarships are available for Mexican graduate students to enhance their capacity in environmental science, engineering, and toxicology.
Specialized Workshops: Workshops for graduate students, environmental professionals, and University faculty interested in topics ranging from bioremediation of environmental contaminants to harmful impacts of heavy metals in children.
Collaborative Projects: The projects address common environmental contamination problems within the Border region:
- Arsenic and Health - Diabetes and Breast Cancer
- Long-Term Effects of Heavy Metals on Children's Health
- Landfill Leachate Plumes - Characterization, Natural Attenuation, and Bioremediation
Mine Tailings - Characterization, Phytostabilization and Phytoremediation