What are the symptoms of thallium poisoning?

The hazards caused by thallium poisoning are relatively large, so in order to effectively reduce these hazards and adverse effects, we need to pay attention to understanding the symptoms. The most common ones are hair loss or peripheral neuritis, which can cause numbness and movement disorders in the lower limbs.

1. Hair loss and skin damage

Hair loss is a specific symptom of thallium poisoning. All patients with thallium poisoning will lose hair after the poisoning reaction occurs. Not only the head hair will fall out, but also the beard, armpit hair and pubic hair will fall out, but the eyebrows usually do not fall out.

Hair loss symptoms usually occur 1 to 3 weeks after acute thallium poisoning, and in the shortest case, hair loss may occur within 4 days. Hair loss caused by thallium poisoning causes hair to fall out in clumps, resulting in alopecia areata. This hair loss is usually reversible, with hair generally starting to regrow about four weeks after the poisoning is cured and fully recovering in three months, but there are reports that severe poisoning can lead to permanent hair loss.

2. Neurological symptoms

Thallium can cause peripheral neuritis. Patients begin to experience numbness in both lower limbs within 12 hours to 1 week after poisoning, followed by pain starting from the ends of the feet. The pain spreads upward as the disease progresses, and a light touch on the patient's skin produces an unbearable burning pain. Subsequently, the patient will develop movement disorders, feel weakness in the lower limbs, and eventually develop muscle atrophy.

Thallium can also affect the optic nerve, causing retrobulbar neuritis, optic nerve atrophy, and loss of light reflex in the macular area. Thallium can also cause eye muscle paralysis and ptosis of the upper eyelid. In addition, due to the effect of thallium, patients usually have white turbidity in the lens. These factors ultimately lead to decreased vision or even complete loss of light perception in patients with thallium poisoning.

Thallium also affects the central nervous system. Patients will experience symptoms such as headaches, sleep disorders, anxiety and even personality changes. Some patients will also show hysterical behavior and engage in hurtful or self-harming behaviors.

3. Digestive system symptoms

Patients exposed to thallium compounds orally may experience early onset of digestive symptoms including nausea, vomiting, loss of appetite, and abdominal pain. In addition, patients often suffer from constipation, which turns into diarrhea as the disease progresses. Some patients may experience symptoms such as stomatitis, glossitis, gingival erosion, and gastrointestinal bleeding. Toxic hepatitis may also occur in some severe cases.