In 2003, a "ricin-containing envelope" was found at a post office in South Carolina. The letter "threatened to poison water supplies if demands were not met." According to the CDC, no one died as a result of the incident.
In 2004, ricin was found in two letters sent to the Capitol Building.
In 2009, a man claiming to have 67 grams of ricin sent letters to managers at 11 Seattle gay bars, threatening to "indiscriminately target at least five of [the clients]" at each bar. According to the letter, the suspect "expect[ed] them to die painfully while in the hospital."
What is the government doing to prevent ricin poisonings?
Sandia National Laboratories is perfecting its toxin detector, which Anup Singh, senior manager of the group working on the device, says is a "four inch by four inch cube" that can use a saliva or blood test to detect ricin exposure in 15-20 minutes. The device can also detect other toxins, such as anthrax and botulinum. He says the "primary goal of the device has been for biodefense."
"Right now it's being developed for medical diagnostics, when we think a lot of people might be exposed. The purpose is to quickly take a saliva sample from a person and screen them," Singh says. "It can also be used for white powder if it's dissolved in water or another liquid buffer."
According to Singh, the device costs about $1,000 and can be used to test multiple people quickly for just a few dollars per test.