In 1971, thallium was the main poison that Graham Frederick Young used to poison around 70 people in the English village of Bovingdon, Hertfordshire, of whom three died. From 1976 to late 1979, thallium was used as a chemical warfare agent, most notably by a unit of the British South Africa Police (BSAP) attached to the Selous Scouts during the Rhodesian Bush War. In 1977, a 19 month-old girl living in Qatar fell ill due to thallium poisoning (from pesticides used by her parents). While doctors were unable to identify the cause, a nurse named Marsha Maitland managed to do it from the description of the symptoms given in The Pale Horse. In summer 1981 the East German secret service "Stasi" poisoned dissident Wolfgang Welsch, who had previously been expelled to West Germany, during his holiday in Israel. He barely survived. In 1985, spiritual leader Rajneesh was allegedly poisoned with small doses of poison, by Reagan Administration and Church, as per accounts of his followers. This allegation was never proven. He died after 5 years in 1990. In 1987, in Kyiv, a woman named Tamara Ivanutina was arrested along with her older sister and parents. They were found guilty of 40 cases of poisoning (13 of them lethal) with Clerici solution obtained from an acquaintance working at a geology institute. Tamara (guilty of nine deaths, including four children) was executed in one of the three documented cases of women receiving the capital punishment in post-Stalin Soviet Union.
In January 2008, 10 members of two families associated with an Iraqi soccer club, including several children, were poisoned by cake contaminated with thallium. Four died, including two children. In 2011, a chemist at Bristol-Myers Squibb in New Jersey, Li Tianle, was charged with the murder of her husband. According to an investigation by the Middlesex County Prosecutors Office, Li Tianle was able to obtain a chemical containing thallium and fed it to her husband. Li was a chemistry student at Beijing University at the time of the highly publicized thallium poisoning of Zhu Ling in 1995 at neighboring Tsinghua University. In 2012 a chemistry postgraduate student at the University of Southampton, UK, was found to be suffering from the effects of thallium and arsenic poisoning after presenting with neurological symptoms. The student underwent an intensive course of treatment and, although he has shown improvement, faces an uncertain long-term prognosis for the recovery of full locomotion. Urine screening revealed elevated thallium levels in a small number of other members of the chemistry department, though none were at toxic levels. The source of the poisoning remains unknown, and although police investigations were fruitless, foul play is strongly suspected. In 2018, authorities charged Yukai Yang, a student at Lehigh University, with the attempted murder of his roommate, Juwan Royal. Yang allegedly poisoned Royal with thallium and possibly other chemicals. Royal experienced vomiting, pain and numbness in his lower extremities, and a long-lasting burning sensation on his tongue.