By Leah Douglas WASHINGTON -The U.S. Department of Agriculture said it has fired 70 foreign contract researchers after a national security review intended to secure the U.S. food supply from adversaries including China, Russia, North Korea and Iran. "USDA has completed a thorough review of individuals authorized to work on contracts with the department and identified approximately 70 individuals from countries of concern," a spokesperson said. "The individuals working on these contracts from countries of concern will no longer be able to work on USDA projects." U.S. Agriculture Secretary Brooke Rollins on July 8 had announced a farm security plan that included efforts to bar purchases of U.S. farmland by nationals of the four countries, and to terminate any existing research agreements with them. Rollins said the moves were necessary to secure the U.S. food supply. The contractors had worked at the Agricultural Research Service, the in-house research arm of the USDA, said Thomas Henderson, president of the American Federation of Government Employees Local 1657, which represents ARS workers in Albany, California. Most of those dismissed were Chinese post-doctoral researchers on two-year contracts with the agency, and who were already subject to vetting before being hired, Henderson said. Some arrived to work on July 9 to find their badges no longer worked, he said. Because of a federal hiring freeze that has been extended through October 15, the USDA will not be able to replace the fired staff and will need to halt ongoing scientific work that benefits farmers, like a project to develop a vaccine for a deadly toxin that occurs in undercooked beef, Henderson said. "We don't have the talent now to progress on these research projects. It's setting us back by years, if not decades," he said. The USDA did not comment on the concern about lost research capacity. The ARS conducts research on agriculture topics like pests, food safety and climate change that are high-priority to American farmers. The agency has lost about 1,200 employees, more than 17% of its 2024 staffing level, to terminations and voluntary incentives to quit offered by President Donald Trump's administration. In a July 8 memo, Rollins prohibited USDA staff from publishing research with foreign nationals from the four "countries of concern" without agency approval and from attending events organized by "foreign adversaries." Some ARS staff were further told in a meeting that all publications currently under review will be re-analyzed and those co-authored with foreign nationals from the four countries will be denied, said Ethan Roberts, an ARS employee and president of the American Federation of Government Employees Local 3247. Before the memo, there were already extra review processes in place to publishing research conducted with people from the four countries, Roberts said. (Reporting by Leah Douglas in Washington; Editing by David Gregorio)