OKLAHOMA CITY - Court documents state an Oklahoma City man arrested in a murder plot mentioned a popular television show before revealing he had Ricin.

Federal agents said Preston Rhoads was planning on killing his pregnant girlfriend and her unborn fetus with the deadly toxin.

The Oklahoma Department of Health told News 9 the state has never had a documented case of Ricin toxicity, but Ricin is a biological weapon.

The use of Ricin was a plot line in the hit television series, Breaking Bad.  Ricin is a potentially deadly toxin made from castor beans. The federal search warrant stated Preston Rhoads asked a friend about the show just moments before showing the friend a vial.

The warrant said Rhoads later revealed the substance was Ricin. The federal search warrant said the materials needed to make Ricin are relatively easy to acquire and the process requires no significant technical expertise.

Agents explained recipes for Ricin are readily available on the internet and in books on unconventional weapons, and Rhoads downloaded a poison manual to find a method.

According to the Centers for Disease Control and Prevention (CDC), Ricin can come in the form of a powder, mist or pellet that is inhaled, ingested or exposed to skin and eyes.

Symptoms include difficulty breathing, fever, cough, nausea, vomiting, seizures and skin irritation. Symptoms can kick in anywhere from four to 24 hours and a high dose can kill within 36 to 72 hours. There is no antidote.

The CDC said Ricin can be very dangerous for first responders as demonstrated Thursday when hazmat crews stripped off their clothing after leaving Rhoads' home in the 11200 block of North McKinley.