# Specifically how dangerous is a 10g chemical sample of pure arsenic and how do you properly dispose of it?

I'm not a chemist. I'm an electrical engineering student and I recently purchased an element collection. The collection came with a 10g arsenic sample. I assumed it wasn't much of a thing because there were no warnings or anything but afterward when I started reading more I became concerned. How dangerous is the really, what precautions must I take in handling the sample, and most importantly how do I properly dispose of this sample?

Thank you

• I would suggest rewording this from "how dangerous is" to "what hazards can be anticipated with" to reduce the risk of a close vote. – A.K. Jul 22 '18 at 19:26
• This may assist you sciencelab.com/msds.php?msdsId=9922970 short version - don't swallow it or inhale the dust – Waylander Jul 22 '18 at 19:50
• Nothing under the Waste Disposal section there :-( . – Oscar Lanzi Jul 22 '18 at 20:15
• Not sure what you have, but most of the elements would need to be sealed (in glass for example) to remain "bright and shiny." A lot of the elements will react with oxygen, water and/or carbon dioxide from the air to at least tarnish if not completely. – MaxW Jul 22 '18 at 23:56
• A sealed bottle of arsenic isn't harmful; ingesting it would be. To get elemental arsenic into your body you would need to create vapour or dust. So don't handle it without gloves, don't heat it and don't eat it. So a sealed bottle in an element collection is low risk. Especially compared to arsenic pigments (once used in wallpaper) which released vapours that really were toxic to random bystanders. – matt_black Jul 23 '18 at 9:03

What you have is a sample of arsenic in its 'metallic' form (it is actually a metalloid). This makes it not as dangerous as you might be imagining. The reason is that As(0) (what you have) is not absorbed easily by the body. What is actually extremely dangerous are soluble forms of arsenic eg. arsenate salts etc. Those are readily absorbed by the body and cause all sort of problems. Arsine ($\ce{ArH3}$) is pretty nasty for example since being a gas is readily absorbed in the lungs.

The above applies for many other compounds, a characteristic example being mercury. We have all heard about how toxic mercury is. However, what most people are not aware is that it is the soluble mercury salts that is the issue here (eg. $\ce{HgCl2}$) and not as much metallic mercury. Actually metallic mercury is very hard to absorb by ingestion or through the skin so if ingested one will most likely survive (according to studies on animals). However, if one ingests the same amount in a soluble salt form (or any other absorbable form, eg $\ce{HgMe2}$) he is in serious trouble (see here: Karen Wetterhahn). The main issue with metallic Hg is its vapors which can again be absorbed so it is not safe to have it in a non confined from (eg, mercury spillage).

Same applies for tin! The metal is (obviously) safe, as well as the salts which are not absorbed by the body. Organotin compounds on the other hand are readily absorbed and extremely dangerous.

Lastly, having been a mineral collector myself many years ago, i used to have a sample too (which i handled with bare hands sometimes something i dont recommend doing) and never had a health issue 20 years now.

In conclusion, i dont think you need to dispose your sample. Keep it in its box and avoid handling it just to be on the safe side as Waylander mentions in his comment. Definitely dont inhale any dust from it although that would be unlikely to happen unless you grind your sample.

Treat this with very great care; don't let it come into contact with you or anyone else as it is readily absorbed through the skin, lungs and gastrointestinal tract.

Arsenic is the classic poison known also to the ancients. Ten grammes is a huge quantity as it is deadly in quantities of approximately 0.1 g in the blood stream. The oxide and compounds such as the arsenate, are far more poisonous than the metal as they replace phosphate in the body (which is harder for the pure metal to do) so someone can be poisoned directly by taking a large dose or by gradual exposure over a period of time.

For a fascinating read on this and other poisons look up 'A is for Arsenic: The Poisons of Agatha Christie' by K. Harkup, publ. Bloomsbury. '

• As pointed out by ANM, it's elemental As not oxide. – Mithoron Jul 23 '18 at 19:35
• @Mithoron Yes he does but there should be oxide on its surface or in the container. It is true that it is possible to 'eat' metallic arsenic as it acts as an antibacterial but eventually poor health results. In some societies, in the past, this has been common. The corpses of such people also do not decompose rapidly for the same reason. – porphyrin Jul 24 '18 at 8:39