# What the purpose of Mercury in this container? **URL:** \ **Category:** Factual Questions\ **Created:** [March 22, 2015, 2:29pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684 "2015-03-22T14:29:11Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![TheSuffolkRam](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@TheSuffolkRam](https://boards.straightdope.com/u/TheSuffolkRam)\ **Post date:** [March 22, 2015, 2:29pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/1 "2015-03-22T14:29:11Z")
Hi All I’ve was reading a website about urban exploration, and for one of their visits they go to an clinic that was abandoned a few years ago: > **[RAF Upwood Clinic, Huntingdon, UK](http://www.bcd-urbex.com/raf-upwood-clinic-huntingdon-uk/)** > > The clinic in the grounds of RAF Upwood was operated by USAF until it closed in 2012. It is much more modern than the rest of the RAF base. In one of the photos, they show metal container with the following written on the side: \*\* Caution - very Toxic System contains Mercury Bio-hazard Levels Between 8.6-8.9mg/kg\*\* You can view the photo below [![](http://www.bcd-urbex.com/wp-content/uploads/2015/01/raf-upwood-clinic-18.jpg) ](http://www.bcd-urbex.com/wp-content/uploads/2015/01/raf-upwood-clinic-18.jpg) For context, the photo appears to be taking in the same place as an air system, so I don’t know if there related. So what is the purpose of this Mercury? Is it to do with the air system or something else? ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [March 22, 2015, 2:39pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/2 "2015-03-22T14:39:47Z")
it might be part of an air cleaning system connected to where mercury was used or stored like for a dental clinic. ---
**Author:** ![bizzwire](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@bizzwire](https://boards.straightdope.com/u/bizzwire)\ **Post date:** [March 22, 2015, 10:24pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/3 "2015-03-22T22:24:44Z")
No clue, although UV lamps often have small amounts of mercury in them. Could it be a UV sterilizing unit? ---
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [March 23, 2015, 12:42am UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/4 "2015-03-23T00:42:32Z")
Just a wag that the metal container is a cyclone separator (like a giant Dyson vacuum cleaner) for the dental offices’ suction system. ---
**Author:** ![TheSuffolkRam](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@TheSuffolkRam](https://boards.straightdope.com/u/TheSuffolkRam)\ **Post date:** [March 23, 2015, 8:58pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/5 "2015-03-23T20:58:17Z")
Thanks for the reply’s so far. But the responses have just raised another related question. Why does a dentist office use mercury for? is it commonly used in clinics? Otherwise is seems odd to have such a large components (seems quite big, looking at the photos) containing a relatively high concentration of mercury (I’m assuming of course 8.6-8.9mg/kg is considered high). My only other thought is, the figure given seems very specific and tight range, which makes me think that the Mercury is not a by product of the system, or removed from the system, but part of it normal operation. Otherwise why not just say “can contain high levels of Mercury” The figure seems too specific to me. (of course I accept the high probability that I’m wrong) ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [March 23, 2015, 9:13pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/6 "2015-03-23T21:13:22Z")
> [@TheSuffolkRam](#): > > Why does a dentist office use mercury for? [Dental amalgam](http://www.epa.gov/mercury/dentalamalgam.html): > [@](#): > > What is Dental Amalgam? > > Dental amalgam, sometimes referred to as “silver filling,” is a silver-colored material used to fill (restore) teeth that have cavities. Dental amalgam is made of two nearly equal parts: liquid mercury and a powder containing silver, tin, copper, zinc and other metals. Amalgam is one of the most commonly used tooth fillings, and is considered to be a safe, sound, and effective treatment for tooth decay. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [March 24, 2015, 7:42am UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/7 "2015-03-24T07:42:30Z")
> [@TheSuffolkRam](#): > > I’m assuming of course 8.6-8.9mg/kg is considered high Lethal Hg doses vary from 14–57 mg/kg depending on what compound it is, and mercury can be accumulative, so yeah, that’s frighteningly high. ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [March 24, 2015, 1:14pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/8 "2015-03-24T13:14:00Z")
> [@MrDibble](#): > > Lethal Hg doses vary from 14–57 mg/kg depending on what compound it is, and mercury can be accumulative, so yeah, that’s frighteningly high. Hardly frightening. If the substance is deadly at 10 mg/kg, and you have large quantity of it at a 10 mg/kg concentration, you’d have to consume your entire body weight to reach deadly levels.\* Also the form of mercury makes a huge difference (as you acknowledge but perhaps understate). Metallic mercury has very low acute toxicity, and relatively low toxicity from chronic exposure. Organic mercury compounds, on the other hand, are extremely toxic. If the mercury in this container is collected from dental amalgam, it’ll be metallic. I suspect the biggest risk would be to the guy who has to clean the container out on a regular basis. Even then, they’ll be fine with appropriate protective gear (perhaps the right sort of gloves respirator?) \*I work in a bio lab where it seems that knowledge of toxicity is spread by folklore. Lots of people are terrified of chemicals because a former labmate told them to be, so I’ve made a habit of researching actual toxicity data. With most of the mildly toxic chemicals I work with in mg-100 g quantities, I’m not in any severe danger as long as I manage to not eat the entire fucking stock bottle. After looking up metallic mercury toxicity, I’m mentally filing it under “just don’t eat it or huff it”. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [March 24, 2015, 1:20pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/9 "2015-03-24T13:20:40Z")
> [@lazybratsche](#): > > Hardly frightening. If the substance is deadly at 10 mg/kg, and you have large quantity of it at a 10 mg/kg concentration, you’d have to consume your entire body weight to reach deadly levels.\* ? I could eat 240 lbs, of mercury and my life wouldn’t be in danger? ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [March 24, 2015, 1:38pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/10 "2015-03-24T13:38:53Z")
You would have to eat 240 lbs of something containing ~10 ppm (10 mg/kg) of methyl mercury (one of the nastiest mercury compounds) to be at risk of _dying from acute toxicity_. More realistically, if you ate that 240 lbs at a reasonable rate you’d almost certainly suffer effects of chronic exposure. This happened in [Minimata, Japan](http://en.wikipedia.org/wiki/Minamata_disease) where much of the population ate locally caught fish that were contaminated due to high levels of industrial polution. Again, metallic mercury is much less dangerous. You could inject several grams straight into a vein and the biggest harm would be obstruction of blood vessels. NSFW link due to some thumbnails of diseased genitals here: [spoiler][http://www.nejm.org/doi/full/10.1056/NEJM200006153422405[/spoiler]](http://www.nejm.org/doi/full/10.1056/NEJM200006153422405%5B/spoiler%5D) ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [March 24, 2015, 1:56pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/11 "2015-03-24T13:56:04Z")
> [@lazybratsche](#): > > Hardly frightening. If the substance is deadly at 10 mg/kg, and you have large quantity of it at a 10 mg/kg concentration, you’d have to consume your entire body weight to reach deadly levels. Yes, true, but adverse effects will kick in quite a bit before lethal levels are reached, which is the scary part. Although, as you say, if it’s from amalgam (or some other medical [weirdness](http://en.wikipedia.org/wiki/Blue_mass)\*), it’s essentially harmless as long as you’re not vapourizing it. \*Although that particular use must predate that hospital equipment quite a bit. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [March 24, 2015, 1:59pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/12 "2015-03-24T13:59:54Z")
> [@lazybratsche](#): > > … After looking up metallic mercury toxicity, I’m mentally filing it under “just don’t eat it or huff it”. metallic mercury isn’t a massive ingestion hazard. you’ll shit it out. though not a good thing. inhalation is a serious hazard, so don’t huff. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [March 24, 2015, 2:41pm UTC](https://boards.straightdope.com/t/what-the-purpose-of-mercury-in-this-container/715684/13 "2015-03-24T14:41:16Z")
> [@TheSuffolkRam](#): > > I’m assuming of course 8.6-8.9mg/kg is considered high. > [@MrDibble](#): > > Lethal Hg doses vary from 14–57 mg/kg depending on what compound it is, and mercury can be accumulative, so yeah, that’s frighteningly high. Ya’ll are looking at two different concentrations here. The first one is the concentration in the waste – 9 ppm of mercury is I think not trivial, but not instant death either (a broken thermometer is going to give a puddle of 1,000,000 ppm!). The second number is the concentration within a human body, which is a different thing. To turn 9ppm in waste into 9mg/kg in your body, you’d need to eat your body weight in waste AND somehow absorb every single molecule of mercury in the waste. Which will never happen, particularly if the mercury in the waste is elemental, rather than bound to organic molecules already. So again, I don’t have time to check right now whether 9 ppm of Hg (especially not organic Hg) qualifies as hazardous waste, but it’s not something I’d be afraid to be in the same room as. [On edit, what lazybratsche said]