In the wake of letters containing the poison Ricin was sent to a Mississippi congressman and the President, Tennessee Representative Jim Cooper suspended mail delivery to his Nashville District office.
Ricin is a poison derived from the castor oil plant.
It can be deadly if inhaled or injected.
Wednesday night Federal authorities arrested a Mississippi man in connection with mailing the letters. Federal authorities have not released the man's name.
Officials said it's just a precaution and that no specific threat has been made on the Cooper's office.
One of the letters was mailed to Republican Congressman Roger Wicker. A separate letter was mailed to President Barack Obama.
The letters were intercepted at an off site mail processing facility before it reached Sen. Wicker's office and the White House.
However, mail delivered to the district offices is not prescreened prior to delivery.
"I think that all of us are potentially vulnerable so it is better to be safe than sorry," Chief of Staff Lisa Quigley said. "There is no reason to test fate, so for the next few days at least we are ceasing deliveries all together."
Quigley worked on Capitol Hill in 2001 when five people where killed and 17 sickened by Anthrax that was mailed in envelopes to various people including Democratic Senators, Tom Daschle of South Dakota and Patrick Leahy of Vermont.
"I think my first thought was this is happening again," Quigley said. "This was not a good situation and I was really worried about people who handle the mail."
Congresswoman Marsha Blackburn's office said they were reviewing safety protocols with federal authorities, but had no plans to suspend mail delivery at district offices at this time.
Senator Bob Corker's office also decided not to suspend mail delivery.
"No suspicious letters have been received in any of the senator's offices in Tennessee or Washington," Chief of Staff Todd Womack said. "Our staff continues to follow standard Sergeant at Arms protocol for handling mail and will report any suspicious mail to the appropriate authorities."
At the Tennessee State Capitol the Tennessee Highway Patrol handles the security of mail received.
The Tennessee Department of Homeland Security said they are confident in the screening processes for mail, but would not elaborate citing security reasons.