Thallium+(Silver+Class)

Dakota Townsend

Abstract-

Thallium is used in, glasses manufacturing, infrared optics, rat poisoning, smelting, coal burning, cement production, oxygen analyzers and photocells. It is an odorless, tasteless and colorless product and it can be absorbed through inhaling or ingesting. To get rid of it takes quite a while, when it finally does leave it will exit through urine or feces. Most of the US’s supply is imported form other places. Thallium can be found in manganese nodules on the ocean floor and is abundant in the earth’s crust.

It can commonly enter your body by direct contact with the skin. By eating food from your backyard. Drinking water contaminated by thallium or breathing the air inside of chemical plants. People who smoke have twice as much thallium in their bodies than any non-smokers. Death can happen if 1 gram or more is entered into the body at one time. When it comes in contact with the air it starts to degrade. Thallium is available commercially. It’s found in crooksite, lorandite and hutchinsonite and is present in pyrites. General sale of thallium has been banned from the United States and Britain for a while now. Last, it has been banned as a rat poison in the US in the 1970’s.

My view on the chemical is that it should be banned because even though there are some pros there are far more cons. Also, the fact that it is dangerous to the human and potentially fatal is a big factor. Yes it can help smelting and coal burning, it causes way more issues like pollution and disease then it helps us.

Background-

One thing that thallium is used in is glasses manufacturing, when it is added to glass it increases it’s density and refractive index which helps its ability to break light into its component colors. The other reason they are ideal to use is because they have transmission at longer wavelengths and is harder than other infrared optics. Another is an infrared detector, since thallium bromide- iodide crystal’s electrical conductivity changes when exposed to infrared light it is useful to photocells. Next thallium used to be helpful in treating ringworm however this method has been limited because it’s line between toxicity and therapeutic benefit. Thallium is used in electrodes in dissolved oxygen analyzers. Last, it was used in rat poisons because of its colorless, odorless and tasteless characteristics but is not used as a pesticide in the US anymore.

It usually gets exposed into the air from coal burning or smelting. Thallium can be absorbed through inhalation or ingestion. Once entered into the body thallium willingly crosses to the placenta and can be found in breast milk. To get rid of it from the body tissue it takes some time because it can only exit through urine or feces.

Thallium doesn’t exactly do anything positive in it’s original form. In some cases it is used, as poison since contact with the skin is dangerous and thallium vapor could possibly be carcinogenic. It can be found in manganese nodules on the ocean floor. So it can be pretty much found around the world then I’m supposing, yet most of the US’s supply of thallium is imported. Also, you can obtain it by smelting lead and zinc ores. Last, thallium supply is abundant in the earth’s crust that is estimated to be about 0.7 mg/kg.

Health+Evironmental-

Thallium can enter your body by eating food that is grown in your backyard, breathing the air and drinking the water. However the prominent exposure takes place when you eat food. Tiny amounts of thallium are released into the air from cement factories, smelting operations and coal burning power plants, and then falls out of the air into fruit and vegetable gardens therefore contaminating the soil. It can easily enter your food because once in the soil the plants can absorb it through the roots. Also, thallium can be obtained by the body through breathing in the chemical in power plants or contact with their skin. Next, if you live near a chemical site the thallium compounds can mix easily with the water and contaminate your water source. Last, people who smoke have twice as much thallium in their bodies than non-smokers.

Thallium can affect the nervous system, lung, heart, liver and kidney if immense amounts are eaten or drunk for brief periods of time. You can also lose hair, start vomiting, have headaches, loss of reflexes, and have diarrhea if you are exposed to huge amounts of thallium. Death can happened if as little as 1 gram of thallium is entered into the body. Thallium leaves your body very slowly and most of it only leaves in urine or feces in some cases. It can be found in urine up to 2 months after it first entered.

Thallium mostly interacts with the air I would say because almost all the time that’s the way it is exposed into the environment by smelting, coal burning or cement factories. Then the soil would be the next part of the environment it interacts with because once it drops from the air it gets absorbed by the soil. Overall thallium contaminates any system or process that it comes in contact with, it doesn’t do much good for the plants air or water. Thallium degrades as soon as it is exposed to air. Its metallic look quickly tarnishes to a blue/gray color and looks like lead. Also a thick layer of oxide will build up if left in the air. When it is in water thallium hydroxide is formed. A few compounds of thallium are Fluorides: (TIF,TIF3), Chlorides: ( TICI, TICI2, TICI3) and Bromides: ( TIBr, TI2Br4)

Synthesis/Production Section-

Thallium is not usually made in a laboratory it is available commercially. Crude thallium is in flue dust just like arsenic, cadmium, indium, germanium, lead, nickel, selenium, tellurium, and zinc. The most common thing that it is used in used to be rat poison. Even though it was harmful to humans it was an effective rodent killer. A few chemical reactions with thallium are: Reaction of thallium with air- 2T1+O2→TI2O Reaction of thallium with water- 2TI+2H2O→ 2TIOH+H2 Reaction of thallium with fluorine, chlorine and bromide- 2TI+3F2→2TIF3 2TI+3Cl2→2TICl3 and 3Br2→ 2TIBr3

Thallium is found in crooksite, lorandite and hutchinsonite and is present in pyrites. You can get it from roasting of this ore connected with the production of sulfuric acid. To get thallium is very hard but it depends on the source of it.

Economic/Political Impact-

Thallium was banned as a rat poison in the US in the 1970’s, but there is still commercial use throughout the US. Usually thallium isn’t really exported by the US just imported. I think that if thallium where banned people would be affected in the sense of what garden grown food they eat and the water they drink. If thallium were banned then they wouldn’t be able to use it in factories to smelt or burn coat. So therefore it cannot contaminate nearby gardens and water sources. Although this would be bad for the factories it would be good for humans because even though there is no real evidence of it hurting us, we might not want a potential poison in our food. Also, I think that optic glasses lens companies would feel the hurt because they use thallium in there to make the lenses stronger. Last, photocells would be affected. Thallium is no longer exported by the United States. All of the thallium that is in the US is obtained from imports. General sale of thallium has been banned in the US and Britain for some time now. Last, if thallium were banned I think that it would benefit the average American. Mostly because the water will be a lot cleaner if you life near a coal and or cement plant/factory. Or your food will not contain something that used to be used as a rat poison. And Last your air will not be polluted with thallium particles.

Summary-

Thallium has more cons then pros, mainly because it doesn’t benefit the human when it comes in contact with the body. Therefore many think that it should be banned because it is very harmful. Thallium can heavily poison you and potentially kill you if it is a high enough level of it. By eating food that is grown in your backyard you might be at risk of ingesting small amounts of thallium. This occurs when you live near chemical plants, cement factories and coal burning plants. Next it can enter your body by your water source, air and direct contact with the skin. It’s harmful to you because it can affect the nervous system, lung, heart, liver and kidneys. If 1+grams enter the body you could die. Also, this is not a good thing to have around pets or children since it’s colorless, odorless and tasteless. Yes thallium has many things going against it but if we banned it then our glasses would be a lot weaker. Infrared optics would have shorter wavelengths. It is used in many everyday things that we use. Like switches, how would we turn things on and off? It’s used in smelting and coal burning and even thought that might pollute the air we need it. I’m not sure if we should ban or keep thallium it seems like there is a pretty good argument on both sides.

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