Todor Zhivkov to 1988, Bulgaria won an unprecedented 153 Olympic medals and numerous European and world competitions in sports as diverse as volleyball, rhythmic gymnastics and wrestling. Dissent was punished under Zhivkov's rule. The CSS was a feared tool of control, and overt opposition largely stayed underground until the late 1980s. In 1978, the Bulgarian dissident Georgi Markov was assassinated in London by an agent who stabbed him with an umbrella tip which implanted a very small ricin ball. According to former KGB general Oleg Kalugin, this was requested by Zhivkov and either performed by the KGB or it assisted the CSS;
Ricin is largely restricted to the gastrointestinal tract, where it may cause mucosal injuries. With appropriate treatment, most patients will make a decent recovery. Because the symptoms are caused by failure to make protein, they may take anywhere from hours to days to appear, depending on the route of exposure and the dose. When ingested, gastrointestinal symptoms can manifest within 6 hours; these symptoms do not always become apparent. Within 2 to 5 days of exposure to ricin, effects of ricin on the central nervous system, adrenal glands, kidneys, and liver appear. Ingestion of ricin causes pain, inflammation, and hemorrhage in