An American Indian tribe in Maine is testing hemp as a phytoremediator to clean up 600 polluted acres of its land.
The Aroostook Band of Micmacs regained the land in 2009, when the U.S. government turned over the former Loring Air Force Base to the tribe, but the land was so polluted that it was categorized as a federal Superfund site.
Many of the toxins have since been removed but there are still concerning toxicity levels in the soil and water.
Through an ongoing research collaboration between members of the Micmac Nation, along with Limestone, Maine-based environmental firm Upland Grassroots and scientists in Connecticut and Virginia, the tribe is investigating industrial hemp’s ability to extract perfluorooctanesulfonic acid, commonly known as PFOS, from the soil.
PFOS, along with inorganic per- and polyfluoroalkyl substances or PFAS, are “forever chemicals” used in industrial and household products, and have been found to pose human health risks.
Dangerous levels of PFOS and PFAS have been found in soil and groundwater as well as meat, eggs and dairy products, leaving health agencies scrambling to find ways to identify, mitigate and remove these health hazards, reported the Bangor Daily News.
If the research project is successful, planting hemp would be the first known solution for absorbing chemicals from the soil, according to the group.
Maine’s Department of Environmental Protection is “actively looking for ways to manage, treat, and dispose of PFAs in the soil because there is no clear and cost-effective solution at this time,” said David Madore, deputy commissioner of the Maine DEP.
“With the research being done at Loring, hemp may turn out to be an option [and] we support this and other efforts to find a solution to the PFAS problem and welcome opportunities for future collaboration.”
The research group planted several small plots of industrial hemp fiber varieties in polluted soil. Once mature, it was harvested and sent to the Connecticut Agricultural Experiment Station for testing.
PFOS concentrations decreased in the hemp plots, according to environmental chemist Sara Nason, an assistant scientist at the station. Data also showed that several PFAS chemicals had accumulated in hemp plant tissue.
Next, researchers will evaluate where the chemicals are stored in the hemp plant and what happens to them.
A larger hemp crop is planned for this summer.