Thallium: Guaranteed Baldness

Thallium is a toxic ultratrace element for the human body. Its toxicity is due to the disruption of the ionic balance of the main cations in the body – sodium and potassium.

    The daily requirement of thallium for the human body is not precisely defined. It is assumed that the optimal daily intake of thallium is about 2 µg.

    The daily intake of thallium from food is insignificant; however, thallium is very well absorbed in the intestine. Just like potassium, thallium accumulates within cells in the body. Both in normal conditions and during thallium intoxication, this element is mainly concentrated in the kidneys (in the medullary layer), liver, muscles, endocrine organs, thyroid gland, and testes. Thallium is primarily excreted in feces through secretion from the internal environment of the body into the intestine. This process is accompanied by competition between potassium and thallium. The excretion of thallium through the kidneys is generally insignificant, even in the case of poisoning.

    Biological role in the human body. Thallium has pronounced toxicity, due to the disruption of the ionic balance of the main cations in the body – sodium and potassium.

   The thallium ion tends to form stable compounds with sulfur-containing ligands and thus inhibits the activity of enzymes containing thiol groups. Thallium disrupts the functioning of various enzyme systems, inhibiting them, thereby preventing protein synthesis.

   Since the ionic radii of potassium and thallium are similar, they have similar properties and can substitute for each other in enzymes. The thallium cation has a greater ability to penetrate through the cell membrane into the cell compared to potassium. The rate of thallium penetration is 100 times higher than that of alkali metals. This causes a sharp shift in the Na/K equilibrium, leading to functional disorders of the nervous system.

    The fact that thallium is an isomorphic “microanalog” of potassium indicates that the toxicity of its compounds for humans is significantly higher than that of lead and mercury.

    Synergists and antagonists of thallium. Antagonists of thallium are substances containing sulfur.
    Thallium suppresses the absorption of iron and can displace potassium from the body.

   Signs of thallium deficiency: scientific data is lacking.

     Increased thallium content. Thallium has pronounced toxicity. The lethal dose for humans is 600 mg.
     Sources of thallium poisoning can include household products: chemicals designed for rodent control – rodenticides (thallium sulfates).

    The risk of chronic thallium poisoning is present for workers engaged in industries such as pyrite roasting, ore smelting (sulfide ores, potassium-rich minerals), coal burning, semiconductor production, cement manufacturing, and special glass production with thallium additives. Thallium can also enter the body through contaminated food products or dust.

      In forensics, there have been cases of using thallium salts for murder or suicide.

    In the case of acute thallium poisoning, the peripheral nervous system, central nervous system, heart, smooth muscles, liver, kidneys, skin, and hair are primarily affected. Thallium causes diffuse damage to neurons in the central nervous system.

    Main manifestations of thallium excess: severe pain resembling neuralgia; hyperesthesia in the limbs (approximately from the 4th day after oral intake of thallium), later paralysis may occur, insomnia; hysteria; visual disturbances; confusion, tachycardia (resistant to standard therapy); lesions of the sweat and sebaceous glands of the skin; hair loss due to keratin synthesis disruption (on the 10th–13th day after poisoning or somewhat later).

    Thallium is necessary: thallium compounds are used for hair removal in tinea capitis – thallium salts in appropriate doses lead to temporary baldness. The widespread use of thallium salts in medicine is hindered by the fact that the difference between therapeutic and toxic doses of these salts is small.

    Some silicates and phosphates of alkaline earth metals, activated by thallium, are used in physiotherapy.

Dietary sources of thallium: beetroot, spinach, grapes, raisins, pomegranate, pear, fig, dried fig, feijoa, soft wheat, hard wheat, long-grain white rice, short-grain white rice, brown unpolished rice, wild rice, rye, barley, chicory roots, tobacco.

    What is the role of thallium in plants?