Extensive pesticide use over several decades has resulted in the contamination of soils and water bodies. Pesticides can either these ecosystems either by intentional application, or incidentally by spray drift, surface water runoff, or spills. These pesticides may have a variety of detrimental effects on aquatic and terrestrial organisms, and could lead to disruption of the ecosystem. Cleaning up contaminated sites by conventional methods, such as excavation and storage off-site, can be expensive and not practical for areas with only minor contamination issues. In the last several decades, in situ methods of remediation, such as bioremediation and phytoremediation, have gained traction as low-cost, alternative clean-up methods.
Much of the phytoremediation work in this lab has focused on using prairie grasses native to Iowa, such as big blue stem and switchgrass, to help remove herbicides like atrazine and metolachlor from contaminated soils and water bodies. Typical studies involve the plants being exposed to field-collected soils from contaminated sites, or simulated surface water runoff spiked with pesticides. Concentrations of the pesticides are monitored over time to determine the effect that the grasses have on the dissipation, movement, and bioavailability of the pesticides. Radiolabeled pesticides have been used to track uptake and metabolism of the pesticides in greater detail, allowing for mass balance studies to determine the distribution of the pesticides and their metabolites within plant tissues.
Some relevant publications:
Albright, V.C., III, I.J. Murphy, J.A. Anderson, J.R. Coats. 2013. Fate of atrazine in switchgrass-soil column system. Chemosphere 90(6): 1847-1853.
Murphy, I.J. and J.R. Coats. 2011. The capacity of switchgrass (Panicum virgatum) to degrade atrazine in a phytoremediation setting. Environ. Toxicol. Chem. 30: 715-722.
Henderson, K.L., J.B. Belden and J.R. Coats. 2007. Mass balance of metolachlor in a grassed phytoremediation system. Environ. Sci. Technol. 41: 4084-4089
Arthur, E.L., P.J. Rice, P.J. Rice, T.A. Anderson, S.M. Baladi, K.L.D. Henderson, and J.R. Coats. 2005. Phytoremediation – An overview. Crit. Rev. Plant Sci. 24: 109-122.
Belden, J.B., T.A. Phillips, and J.R. Coats. 2004. Effect of prairie grass on the dissipation, movement, and bioavailability of selected herbicides in prepared soil columns. Environ. Toxicol. Chem. 23: 125-132.