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Why are thallium compounds dangerous?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — boron group element Modern version of the periodic table of the elements (printable).

Thallium compounds are highly toxic substances that pose significant health risks to humans. Exposure to soluble thallium compounds can lead to severe poisoning, which may be fatal.12

The primary health effects associated with thallium toxicity include:
* Nervous system disorders: Damage to the nervous system can occur following exposure.1
* Gastrointestinal issues: Ingestion or contact often results in significant gastrointestinal distress.1
* Hair loss: A characteristic symptom of thallium poisoning is rapid hair loss.1

It is important to note that the metal itself is not inherently safe; contact with moist air or skin can cause the metal to convert into these dangerous, soluble compounds. Due to these severe health hazards, the use of thallium compounds as pesticides and insecticides was largely discontinued in the 1960s.1