The FBI has warned law enforcement agencies that terrorists may use nicotine (search) and solanine (search) as "mass poisoning agents."

Nicotine can be obtained from tobacco. Solanine can be obtained from potatoes.

"References to nicotine and solanine appear in numerous terrorist training manuals and documents seized in Afghanistan," the FBI said in its weekly bulletin to law enforcement agencies, which was sent out late Wednesday. "The most likely technique for nicotine or solanine poisoning would be food, beverage or water contamination; however, nicotine can also be absorbed through the skin and mouth and the digestive and respiratory tracts."

The FBI said terrorist manuals "detail simple instructions" on how to produce both poisons. The FBI also said it "possesses no specific information indicating terrorists plan to use nicotine or solanine in a future attack."

Acute nicotine poisoning will cause central nervous system depression, neuromuscular paralysis, lowered blood pressure, slowed heart rate and death. More common symptoms of nicotine poisoning include nausea, vomiting and abdominal pain, the FBI said.

Common symptoms of solanine poisoning occur two to 24 hours after exposure and include a harsh, scratchy sensation in the mouth, dehydration (search) and drowsiness. Severe cases include cramps and fever -- and can result in coma and death, the FBI said.

The federal law enforcement agency also said: "There are no known instances of actual use of either poison by Islamic terrorist organizations; however, nicotine was used in a recent domestic criminal poisoning incident, resulting in the sickening of nearly 100 people in Michigan."

The lethal dose of nicotine is about 40 to 60 milligrams. Solanine occurs naturally in "greened" potatoes, produced when the potato is old or exposed to sunlight for long periods of time, the FBI said. A large dosage of solanine is necessary to be fatal, the bureau said.

In the second portion of the FBI bulletin, the bureau notes the upcoming second anniversary of the Sept. 11 attacks.

"Threats of undetermined reliability continue to be received and investigated by the FBI," the bureau said. "Several of these threats make references to the events of September 11, 2001.

"The FBI possesses no specific information indicating that terrorists are planning attacks to coincide with the second anniversary of the September 11 attacks. Although Al Qaeda is not known to use anniversary dates as a factor in timing terrorist operations, increased attention in routine security planning is warranted," the FBI said.

"While international counterterrorism efforts have eroded the capacity of Al Qaeda to plan and carry out similar large-scale attacks against U.S. interests, Al Qaeda must continue to be viewed as a capable and determined terrorist network, committed to attacking U.S. and Western targets in multiple venues, including the United States."

Fox News' Anna Stolley contributed to this report.