Small quantities of thallium, a heavy metal that is highly poisonous, were apparently produced under the auspices of Project Coast. This was done either at Delta G Scientific, the principal South African CW research and production facility, or at Roodeplaat Research Laboratories (RRL), the main BW research, testing, and production facility. Some of this thallium was added to foodstuffs and then deployed to contaminate targeted enemies.

Dr. Johan Koekemoer of Delta G expressed doubt that thallium had ever been produced at his facility. However, at the request of Commandant Ian Joubert, he had tested the blood and urine samples of several policemen from the Koevoet ("Crowbar") counterinsurgency unit who had been poisoned; after detecting thallium in the samples, he manufactured a substance to purify their systems (since there was not enough Prussian Blue available in South Africa). Even if thallium was not manufactured at Delta G, there can be no doubt about its availability at RRL. Dr. Stiaan Wandrag worked there to develop CBW antidotes, ostensibly for the protection of VIPs, and in this capacity carried out research on thallium and other toxic materials. Dr. Mike Odendaal and Dr. James Davies were likewise involved in testing the effects of various poisonous substances at RRL by mixing them into food and beverages. After producing these poisons and contaminated items, they handed them over to Dr. André Immelman, RRL's R&D director. Odendaal also regularly provided Immelman with instructions concerning dosages and safety precautions for handling the dangerous substances he made. Immelman then stored these and other lethal materials inside a refrigerator in a bombproof, fireproof walk-in safe in his office.

On the purported instructions of Project Officer Wouter Basson, Immelman later secretly transferred thallium and other highly toxic substances to military and police personnel through various channels. Some of these dangerous materials were provided to Dr. R. F. Botha (alternately known as "Koos", "Mr. R", and "Frans Brink") and thence to Vernon Lange (otherwise known as "Mr. T" and "Theo"), both of whom were operatives of the Civil Co-operation Bureau (CCB), a covert assassination unit operating under the aegis of the Special Forces (SF). Others were provided directly to Chris Smit, Gert Otto, and Manie van Staden, three Security Branch (SB) officers from the South African Police (SAP). According to the 1989 "sales list" (TRC document 52), as well as firsthand testimony at the Truth and Reconciliation Commission hearings or Basson's criminal trial, Immelman passed such items on, either to the aforementioned persons in innocuous public places like restaurants, or to Basson himself in the latter's office at South African Medical Services (SAMS) headquarters in Centurion. Another reported recipient of RRL's poisons was Johnny Koortzen, an ex-South African Defence Force (SADF) psychologist who in 1988 assumed control over Systems Research and Development, a company that bioengineer Jan Lourens had set up in part to manufacture special "applicators," i.e., arcane assassination devices. Some of these toxic materials and devices were subsequently used to assassinate designated "enemies of the state"—guerrillas in neighboring countries, troublesome prisoners, untrustworthy members of the security forces, or activists in the African National Congress (ANC) and other South African opposition groups.

Among the items that appear on the "sales list" is thallium acetate, an extremely poisonous compound that was listed as having been distributed by Immelman to both Koortzen and Chris Smit. Immelman also testified that on several prior occasions he had transported thallium and thallium-laced beer and whiskey over to Basson's office at SAMS HQ, and Basson himself acknowledged that he had obtained these and other dangerous items from Coast scientists. Later, it emerged that several individuals who had been targeted by special operations units were apparently poisoned with thallium, including ANC student activist Sipiwo Mtimkulu, talkative SF member Victor de Fonseca, and possibly even Steven Biko. Moreover, according to Dr. Schalk van Rensburg of RRL, Immelman had expressed great confidence that Nelson Mandela's brain functions would be progressively impaired following his release from prison—remarks that were echoed by both allusions in the minutes of the March 1986 State Security Council meeting and by newspaper articles reporting that doctors working with Basson revealed that he intended to poison Mandela with thallium. When confronted with these allegations, Basson insisted that he and other SADF personnel had in fact carried out training exercises designed to prevent Mandela from being poisoned by his rivals within the ANC. Basson's claims cannot be accepted at face value, however, especially given the South African penchant for using toxic substances to murder or sicken proclaimed enemies. For example, under the rubric of "Operation Dual," a clandestine program initiated by the SADF in 1979, chemical agents were regularly used by the D[elta]40 and Barnacle units—the CCB's predecessors—to secretly eliminate prisoners and security risks. According to Johan Theron, the SADF's chief executioner, this program was sanctioned from the outset by General Fritz Loots, the first commander of the fledgling SF. With the establishment of the Teen-Rewolusionêre Inligting Taakspan (TREWITS: Counter-Revolutionary Intelligence Task Force) in the mid-1980s, the "Dual" assassination program was later expanded and coordinated at an even higher level. In this context, the fact that certain Koevoet members contracted thallium poisoning can probably be ascribed to their own ill-fated efforts to employ the chemical to murder others.

In 1990 President F. W. De Klerk prohibited the carrying out of any further work on lethal CBW agents, and in 1993 Project Coast was officially terminated. The stocks of standard CW agents produced by South Africa were supposedly destroyed in conformity with international agreements, despite the fact that the actual destruction process was never independently verified. Although several chemical plants there continue to produce highly toxic substances for normal industrial and agricultural use, none of these substances appear to be intended for deployment as lethal anti-personnel agents. The current government still has access to the type of technical expertise and the sort of sophisticated R&D facilities that would enable it to initiate a new CW program, but there is little reason to suppose that it has any interest in doing so.

	Updated March 2004