Where ricin is involved, preliminary tests can be inaccurate. Full laboratory tests will be needed to confirm the poison’s presence.
Lawmakers were made even more nervous by reports from some states that district offices were also getting questionable mail. Republican Sens. Jeff Flake of Arizona and John Cornyn of Texas both said that letters set aside as suspicious by staff members back home had been tested by law enforcement and found harmless. Democratic Sen. Carl Levin of Michigan said a letter sent to his Saginaw office was still being checked.
Meanwhile, at least three questionable packages turned up in Senate office buildings, according to the AP. Capitol Police retrieved them while establishing a series of rolling lockdowns throughout some areas of the Senate side of the Capitol Hill complex. Confused Senate aides took to social media to share which corridors were open and which closed.
Ricin is a potent toxin found in the seeds of the castor plant. Touching it can produce a rash that is irritating but not fatal. Inhalation or ingestion of ricin particles is more dangerous, leading to death in three to five days if the dose is sufficiently large.
Ricin is not difficult to extract – the production of castor bean oil results in a mash that is approximately 5 percent ricin, for instance. Recipes for making the poison are readily available on the Internet and from commercial bookstores.