# Thallium Use, Toxicity, and Detoxification Therapy: An Overview
## 6 Uses of Thallium  
The US Geological Survey estimates that the annual worldwide production of this metal is about 10 metric tons as a by-product from the smelting of copper, zinc and lead ones. About 17 million kilograms of global thallium resources are contained in zincores in Canada, the United States and Europe, whereas 630 million kilograms are in the world's coal mines [17]. In the 1930s, thallium was used to treat venereal diseases (e.g., syphilis and gonorrhea), malaria, and ringworm as a depilatory agent. Thallium salts were first used as pesticides in Germany in the 1920s, and because of their severe toxicity eventually became used as rodenticides. However, after several poisonings, thallium use as rodenticide was banned in the United States in 1965 [47]. The odorless thallium sulfate and acetate have been used to kill rats, squirrels, and ants; however, after many cases of unintentional poisoning, it was banned in Western countries. Unfortunately, cases of thallium poisoning are still reported in countries where it is still illegally used as a rodenticide and ant killer. There is an increasing contemporary demand for thallium in advanced industrial technology. It is used in the manufacture of electronic equipment, camera lenses, semiconductor materials (TI selenite), scintillator counters, laser equipment, low-temperature thermometers in alloys with mercury, and photoelectric cells. Special  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Food** & **TI (\(\mu\)g/Kg)** & **References** \\ \hline Bream & 800–8600 & [41] \\ \hline Brook trout & \(>\)3000 & [41] \\ \hline Mollusks & 350–2930 & [41] \\ \hline Shellfish & 350–2930 & [41] \\ \hline Fish & 350–2930 & [41] \\ \hline Red and white wines & 40–480 & [41] \\ \hline Vegetables and cereals & 20–300 & [41] \\ \hline Red meat & 50–70 & [41] \\ \hline Potatoes (dry weight) & 20–30 & [41; 53] \\ \hline Milk & 10–30 & [53; 54] \\ \hline Poultry & 2.8 & [54] \\ \hline Porcine (dry weight) & 1.7 & [55] \\ \hline Tobacco per cigarette & 1.1–2.4 & [56] \\ \hline \hline \end{tabular}
\end{table}
Table 3: Food sources of thallium.  
glass with a high index of refraction is prepared from thallium oxide. It is also used in imitation jewels and artificial diamonds, green fireworks, yellow-greenish glass (TI sesquioxide), in the production of pesticides, phosphate fertilizers and in the impregnation of woods and leather against fungi and bacteria [17, 31, 41]. In medicine, the most important use of \({}^{201}\)TI (TICI) is as radiological contrast agent in scintigraphy imaging of the heart, liver and testes, and in tumor visualization. Thallium, as a pharmaceutical cosmetic product, is applied for facial hair removal and fungal infections of the scalp [57]. Thallium acetate is currently used as a catalyst in organic synthesis in the oxidation of olefins and hydrocarbons, and in epoxidation and polymerization reactions [58]. Detection of TI is a challenging task because its concentration in environmental samples may be at a nanogram per gram level or lower. Most studies for the determination of TI are conducted in water matrices. Mass spectrometry, atomic absorption spectrometry and voltammetry are key analytical techniques used for the determination and monitoring of TI in environmental samples [59, 60, 61].