Superfund Research Program
Engineering Enhanced Plants for Arsenic Remediation
Project Leader: David A. Lee
Grant Number: R41ES016961
Funding Period: Phase I: September 2008 - August 2009
Arsenic is one of the most serious environmental contaminants in the United States. The traditional method for arsenic remediation involves excavating the contaminated soil and disposing it in hazardous waste landfills. This method is highly labor intensive and costly, especially for large sites. An alternative remediation technique is phytoremediation, the use of plants to remove toxins from contaminated soils or water and concentrate the toxins in the biomass compared to the environment. Edenspace is an industry leader in the use of plants to remediate arsenic from contaminated soil or water, and has worked on numerous sites across the country. Arsenic phytoremediation currently uses an arsenic-accumulating fern plant. While this perennial tropical plant is effective is accumulating and removing arsenic from the soil, its use is limited by the need to transplant young plants rather than growing plants from seed, and by its low tolerance for sustained temperatures below -5xC. Development of alternative crops that are more widely adapted with similar abilities to accumulate arsenic will provide enhanced capabilities to address the problem of environmental arsenic. For this STTR project, Edenspace and its research partner, the University of Massachusetts (UMass), propose to develop enhanced plants for arsenic phytoremediation. A number of plant and microbial genes have been isolated and characterized that confer fourfold increases in arsenic tolerance and uptake in the model plant Arabidopsis thaliana. Because this plant has low commercial potential for remediation due to its small size, the team will bioengineer a highbiomass, non-food variety of a row crop, Brassica napus, with the transgenes. In Phase I, Edenspace will confirm that the transgenic B. napus shows the same arsenic tolerance and uptake phenotype observed in transgenic Arabidopsis, which will lead, in Phase II, to a small scale field demonstration.
Arsenic is a highly toxic substance found either naturally in the environment or concentrated by human activity at contaminated sites; it provides significant health concerns to humans and wildlife. This project intends to develop an effective and economical technology capable of removing arsenic from the environment using plants and lowering the public's risk of exposure to arsenic.