Updated

As Capitol Hill goes into rapid reaction to prevent fallout from a ricin-filled letter sent to the Senate, President Bush has ordered three Cabinet departments and the Environmental Protection Agency (search) to work on protecting the nation's food supply.

Bush issued an executive order, released on Tuesday, telling the departments of Agriculture, Health and Human Services and Homeland Security as well as the EPA to develop new methods to respond to terrorist attacks against the agriculture industry.

The directive calls for creation of systems to contain any outbreaks of plant or animal disease that result from terror attack, and to prevent or cure the diseases themselves.

For more on bioterrorism, click to view Foxnews.com's WMD Handbook.

The president ordered the agencies to plan ways to stabilize the food supply and the economy and to help the nation recover after an attack, and ordered them to help agribusinesses (search) develop plans to protect themselves.

"We should provide the best protection possible against a successful attack on the United States agriculture and food system, which could have catastrophic health and economic effects," Bush said in the order signed last Friday.

In his fiscal year 2005 proposed budget, Bush set aside an extra $160 million — or a 4 percent increase — in the HHS budget to focus on rapid detection and enhanced border security related to bioterrorism.

For the USDA, the president has proposed setting aside $170 million for the department's National Centers for Animal Health (search) in Ames, Iowa, which studies animal disease and is part of the USDA's growing food security and bioterror infrastructure.

The department is also planning a national identification system to track livestock, to be in place in July 2005.

Another $60 million was proposed for programs targeted at the detection and prevention of mad cow disease (search), not a terror-related disease, but one that can greatly impact the nation's food supply.

Under the current order, the USDA would develop a National Veterinary Stockpile that would hold enough animal pharmaceuticals "to appropriately respond to the most damaging animal diseases," including foot and mouth and anthrax, within 24 hours of an outbreak. Once the ID system is in place, the cattle and other animals could be tracked down within 48 hours to be administered the drugs.

The executive order says USDA also must create a National Plant Disease Recovery System that could respond within a single growing season to "a high-consequence plant disease" with pest control measures or disease-resistant seed. The paper gave as examples soybean rust and wheat smut.

Under the new plan, the CIA and other government organizations would work with the departments and EPA to find weak spots in the agriculture and food sectors and develop ways, including heightened screening of imported foods, to repair them.

The Homeland Security Department would be in charge of any response to an attack on the food supply, Stump said, and would coordinate combatting an outbreak that threatens widespread risk to human health or the economy.

The Other Biological Agent

The president's order followed confirmation by Senate Majority Leader Bill Frist on Monday that his office mailroom had received an envelope containing ricin (search). As many as 50 Capitol employees were quarantined briefly and decontaminated as a result of the spill, Senate aides, speaking on condition of anonymity, said Tuesday.

On Tuesday, Frist said that ricin is a deadly toxin derived from the castor bean, which is used to make castor oil. Castor oil (search), while used in plastics, textiles, paints, cosmetics, and a number of inks and industrial adhesives, is also sold as an herbal remedy to induce vomiting or as a laxative. Its use dates back to ancient Egypt.

Frist said castor beans can be aerosolized for inhalation, but he has never heard of someone dying from it.

"People work in castor-oil-making factories and they never get sick from it," he said.

He added, "I will say that never, to best of my knowledge, has anybody died from inhalation of a derivative of the castor bean. But we know that in animal models, it is deadly. And it can be very progressive."

Frist said that ricin is not a virus or bacteria, and should not be considered a biological agent because it is not alive.

However, the delivery of ricin to Capitol Hill has again raised questions about the vulnerability of bioterror or chemical attacks on Washington.

In November, an off-site mail sorting facility for the White House found a powdery substance in a letter for the president. It was intercepted before it reached the White House. The substance turned out to be ricin, but it was of such low potency, it never posed a public health risk, said an administration official. The FBI is still investigating that letter, which was believed to have come from a domestic source.

That letter was linked to another letter discovered in October and addressed to the Department of Transportation. The earlier letter was found at a postal sorting facility in Greenville, S.C. The two letters with ricin had similar content — typewritten demands that changes in truckers work-sleep schedules not be implemented.

The FBI is exploring whether this week's ricin incident is linked to those two letters. Officials say the FBI has not yet found an accompanying letter to indicate a linkage.

Frist said Tuesday it was premature to believe that the ricin found in the letter sent to his office was related to terrorism of the kind committed by Al Qaeda, but its mailing definitely constitutes a terrorist act, even if by a domestic criminal.

"The question is whether it's a criminal act or terrorist act. In my mind, they're basically the same," Frist said. "Because it is a poison a toxic chemical that we know is deadly, that we know there is no treatment for that, the assumption is the intent to harm. Because of the nature of the agent, it clearly is intended to terrorize, as well, as we all feel the insecurity that we're here."

Fox News' Jim Angle and Anna Stolley and The Associated Press contributed to this report.