We're back to toxicology today.Thallium has a short but extremely notorious history, Thallium is a scarily effective poison. Only discovered in the 18th century, thallium has become one of the most feared poisons.

Name: Thallium, usually used as a poison in the compound thallium (I) Sulphate

Chemical formula: Ti, usually Ti2SO4

Effect on Victim: Thallium is an extremely toxic element, it's shocking that it saw so much use in the cosmetics industry (a surprisingly common trait among poisons). Thallium (I) compounds are highly soluble so readily absorbed through the skin, even touching Thallium is dangerous. Thallium has been popular as a poison not only because it is so readily absorbed by the body due (due to it's similar structure to potassium which the body needs) but also because it is completely odourless and tasteless, it's undetectable by nose, eye or tongue in almost any drink. Once inside the body Thallium works similarly to serious pneumonia. Acute cyanide poisoning induces nausea, vomiting, shortness of breath and death after about 30 hours. Thallium however displays a far more distinctive symptom when administered in gradual doses, alopecia. Thallium is actually causes hair loss with amazing rapidity, which is why it was used in the cosmetics industry. Thallium actually kills by entering the cells in the place of potassium, through potassium-sodium pumps on the cell's surface. once in the cell, where potassium helps maintain fluid balance in the cell and and feeds nerve cells, thallium disrupts chemical reactions, destroying cells ability to function correctly. Thallium spreads so efficiently that this effect soon becomes body wide.

Lethal Dose: 15-20 mg/kg of body mass

Diagnosis: Thallium gets it's name from the trademark green it exhibits in both a flame test and a spectroscopy test. Suspicions should be aroused by the hair loss associated with Thallium. Confirming these suspicions requires only a spectroscope test of the tissue. Thallium will display a distinctive bright green line.

This is a uniquely bright and vivid green.
You acquire the sample for the test through quite a delicate chemical reaction:
1. Grind down sample of tissue
2. Add nitric acid in excess to the tissue in a flask and leave for an hour
3. Place the flask in a steam bath for 2 hours (until tissue has completely dissolved).
4. Cool and filter solution through glass wool. Place resultant solution over an open flam.
5. Carefully add Sulphuric Acid to the heated solution (acids are much more corrosive when hot).
6. Leave the resultant sludge-like solution to settle down and then slowly trickle nitric acid into it. You should observe this colour change:
 red -> yellow -> colourless
When the solution is completely colourless it is ready. 

There's your basic guide to the analysis of thallium. Thallium is potentially hard to detect due to how similar it is to pneumonia in some respects, however there are warning signs. Just remember to look out for green tinted urine in acute poisoning cases and hair loss in gradual ones. Once again thanks for reading and feel free to comment with suggestions, criticisms, ideas or opinions. Over and out!

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