Kansas City, Mo. ? A biological terror attack on the U.S. food supply could come soon, but many Washington lawmakers aren’t taking the threat seriously, a U.S. senator from Kansas said Thursday.

A successful attack would disrupt the food supply of not just the nation, but the entire world, Republican Sen. Pat Roberts said on the final day of the three-day International Symposium on Agroterrorism.

“Experts in the field warn, this threat is not an ‘if’ but a ‘when,'” Roberts said at the symposium, sponsored by the FBI and its Joint Terrorism Task Force. “The effects of such an attack would be devastating. Halting exports or shipments of agriculture production and all other exports due to contraction of disease by just one animal would have a ripple effect unlike we have seen in the U.S.”

Roberts, former chairman of the Senate Intelligence Committee, played a lead role in getting the $450 million National Bio and Agro-Defense Facility built in Manhattan, Kan., on the Kansas State University campus. That project is scheduled to be completed in 2017 and certified a year later, when the transition of operations from the Plum Island Animal Disease Center off the coast of New York will begin.

While the NBAF is being built, research on biological threats such as anthrax and foot-and-mouth disease is being carried out at the Biosecurity Research Institute housed in Pat Roberts Hall on the school’s campus.

The senator compared the potential impact of an agroterrorism attack to what the nation experienced in 2001 when terrorists crashed commercial airliners into both World Trade Center buildings and the Pentagon.

“The tragedy of 9/11 is an image that will be forever burned into our national memory,” Roberts said. “In the same regard, thousands of terminated cattle, swine or other livestock would also be devastating. Fear about the health and quality of our nation’s food supply would result in catastrophic results on our economy.”

A bipartisan commission said in 2008 that a nuclear or biological attack on the U.S. was likely to happen before 2013, with biological weapons more likely to be used because they are more accessible.

Dr. Ron Trewyn, vice president of research at Kansas State, noted that the clock is clicking closer to 2013 and the nation still isn’t prepared to deal with a devastating attack on its food supply.

“Attacks on the U.S. could ravage food supplies worldwide,” Trewyn said. “The U.S. still feeds the world.”

U.S. agriculture is a $1 trillion business that accounts for 15 percent of the U.S. economy and 18 percent of the jobs, Roberts said.

“Unfortunately, there are those in Washington who still continue to pay little attention to the seriousness of this threat,” he said. “But I can assure you our efforts will not cease.”

Later Thursday, Roberts was scheduled to accept the fourth annual National Security Award from Business Executives for National Security.