Q&A: What is ricin?

Investigators search for Ricin in US Senate buildings in 2004

US authorities have intercepted a letter sent to Mississippi Senator, Roger Wicker, that preliminary tests showed contained the deadly poison ricin. The FBI and other agencies have launched an investigation.

What is ricin?

How is it produced as a poison?

How does it get into the body?

How potent is it?

Is there any treatment?

How would someone know if they were affected?

What other cases are there of ricin being used to poison?

Does ricin have any positive benefits?