But where do I get a pound of mercury?

CDC Morbidity and Mortality Weekly Report

On September 16, 2013, the North Carolina Division of Public Health was notified of an elemental (metallic and liquid) mercury spill on a school bus. An elementary student boarded the bus with approximately 1 pound (454 g) of elemental mercury contained in a film canister, which the student had taken from an adult relative who had found it in a neighbor's shed. The canister was handled by several students before the contents spilled on the bus floor. Ten passengers aboard the bus were exposed, including eight students and two staff members. Although elemental mercury is not readily absorbed from skin contact or ingestion, it does vaporize at room temperatures and inhalation of the vapor can be harmful. The bus driver promptly notified school officials. Firefighters and a local hazardous materials team directed decontamination procedures (i.e., changing clothes and washing hands and shoes) for the 10 exposed passengers. The bus was immediately taken out of service and sent for disposal because of its age and the cost of decontamination.

Two students and three family members reported acute symptoms on the day of the exposure, including headache, cough, numbness or tingling in hands, and difficulty breathing. The student who brought the mercury aboard the bus and five family members, including two adults, had elevated blood mercury levels, ranging from 134 µg/L to >200 µg/L. A blood mercury concentration of ≥50 µg/L is considered the threshold for symptoms of toxicity after an acute high level exposure (2). Two children who had symptoms and blood mercury levels >200 µg/L received a 19-day course of dimercaptosuccinic acid chelation therapy (2). Two other children with elevated blood mercury levels but no symptoms were followed every 2 weeks with urine testing until levels normalized. The two adults were referred to their physician for follow-up.

Through this investigation, six persons with blood mercury levels exceeding human health risk thresholds were identified. Two of these persons required chelation therapy.


Tags: ,

31 Responses:

  1. Ben says:


    It's not a controlled substance. At one job we shipped a lot of it, it was amazing to hold a small bottle full of it.

  2. Will says:

    The estate sale of a dentist? That's where I found mine. Well, it's only a 1/4 lb, but that's probably plenty.
    That's about the size of a bottle of model paint.

  3. pat says:

    Amazon, of course. 98$ for a pound, unfortunately not eligible for Prime.

    Putting together the raw materials for 1 pound of thermite for 20$ is an exercise left to the reader.

    • Will says:

      Since I clicked on that link, Amazon would now like to know if I would like to buy a pound of sodium. Hmm.

  4. Steve Allen says:

    The Bay Area mountains are thick with cinnabar, from Red Rock under the San Rafael/Richmond bridge to an abandoned pit on Mt. Hamilton to the hills around Almaden south of San Jose to beyond. Just gather and heat until the mercury comes out.

    • Walt N. says:

      That's an excellent way to acquire both mercury and die from mercury poisoning. The vapor pressure of mercury rises by several orders of magnitude between 20C and 100C.

  5. nooj says:

    Someone gave me a beaker of it once, like a half liter's worth. Shit was damned heavy! We were all pretty entranced by pouring a bit of it onto the floor, watching it splash into little balls, and then using a piece of paper to scoop it into a puddle. It's easy to push around (it doesn't wet things), and really hard to pick up (it's heavy and a liquid and hard to get stuff underneath it). So we just kept pouring more and more out and not picking up any of it.

    Eventually we had poured the entire thing onto the floor and were standing around looking at this HUGE, exquisite puddle of mercury. And then we looked at the empty beaker. And then back at the HUGE puddle of mercury on the floor. And back to the empty beaker. And back to the HUGE, exquisite puddle of mercury. After a verry pregnant pause as the realization set in, one of us ventured, "Hmmm." We all agreed. "Hmmmmmm."

    So of course we sat down on the floor around it and turned it into a game of Calvinball. It was a long game. We were really really, uh, "patient" at the time.

    Eventually the last of it got back into the beaker, plus a lot of bonus dust floating on top. I guess dust is electrically charged or something. No one was willing to give themselves points for getting their fingers close enough to it to pick the dust out. Probably a good thing.

    Luckily, by the end I was sober enough to realize that while it had been a fun adventure, I would eventually be the confused owner of double-fistful of dusty mercury in a glass container with no lid. I handed it back to him, "Nah, man, I couldn't take it from you. You keep it."

    Never saw the guy again.

    • Injector says:

      See my comment following yours.

      I remember now how my dad found out about the mercury my friend and I had. In the course of playing with it, it started to get dirty, and lose its shine. So my knowing my dad was a smart guy I asked him if he knew how to clean mercury. (It isn't as easy as picking the dust out, we tried. We also tried wiping it with a paper napkin.)

      Thinking back, I'm surprised my dad didn't get very angry about us having it. He just asked where we found it, and how we got it into the container. He did seem a little freaked out when I said that my friend had sucked it up with a straw. He also wanted to know how much we had actually handled it (quite a lot).

    • gronk says:

      The stuff that's still on the floor still evaporates. And makes people sick, as they inhale the fumes. At my high school, we had a teaching assistant who got early dementia (in his 50's). Turned out he was sitting next to a storage cabinet with a broken bottle of mercury; with a simple UV blacklight you could see mercury fumes coming down from the cabinet. Everything was settled with a nice liability suit, but as this happened in europe, he got 50k or something like that. And dementia for the rest of his life. Jay.

  6. Injector says:

    There was lot next door to where I grew up as a kid. The guy who owned it was always working on cars. I have no idea why there was so much mercury spilled there, but one of my friends sucked it up in a straw. That's actually kind of hard to do apparently, as air kept slipping through the liquid--maybe not enough surface tension--but he managed to hold it in the straw long enough to transfer it to a film canister.

    We took it to school, poured it on desks, and scooped it back into the canister with a sheet of paper when done. We had it for a few days until my dad found out about it.

  7. Edouard says:

    Weekly Report? Mmm, thank-you.

  8. Dan says:

    I went to a small college, where our physics teacher had been there for probably 60 years, first as a student then as professor and head of the department. He retired, and when they did an inventory to get ready for the new guy, they found two sealed, never opened 1 gallon containers of mercury. The head of the chemistry department nearly lost it. They took it over, sold a bunch of it, and kept the rest for use in classes. No one ever figured out where it came from or why it was there.

    • gryazi says:

      Commonly needed for vacuum pumps back in the day?

      A coworker's been dealing with parents-in-law who have plenty of issues, including some dementia. The father had been an engineer, and his father before that an inventor of some sort. When they went to put the house up for sale they found a puddle of mercury in the attic... I put them in touch with an environmental company we'd dealt with and as I understand their guy pretty much just chased it down with card stock and gloves, but I wonder how long everyone was breathing it.

      • Dan says:

        It's possible, I suppose, but the stuff was decades old, and still sealed, never opened. And even if you did need it for a vacuum pump, would you need that much?

        • gronk says:

          Mercury diffusion pumps. Ideal for hard vacuum (up to 10^-5 bar), and don't care for any junk in the vacuum. Turbo pumps don't like anything except air. So mercury diffusion pumps are your choice for distilling organic compounds at high vacuum. Two gallons is overkill, but a full refill would require about 250-400 mL (at least for the exemplars I saw).

          • Dan says:

            Sure, for chemistry, there's tons of uses. But what about physics? This was a small college with a tiny physics department, and we never did any experiments with anything like that level of vacuum. The general consensus around campus and in the other departments was: how did he get it, why did he get it, and why didn't he ever use it? Nobody had any answers to that.

  9. In 3rd grade, we passed around a bottle of it in science class and played with it in the pencil trays of our desks. Between that and leaded gasoline, herp derp derp!

  10. I'm kind of surprised nobody has suggested old thermostats as a source of mercury. It was used as part of a sealed switch, and didn't suffer from the problems of arcing damage or oxidation from exposure to air. You'd probably need a lot of thermostats, but at one time they were very common. I had the unbroken mercury bulb from an old Honeywell "round" thermostat in my desk for several years. It was cool just to watch the mercury move around, especially the way it "thumped" at the end of its travel.

    I also dimly recall seeing mercury switches used in tilt switch/sensor applications.

    Ask around at HVAC shops that have been around for a while. They might have suitable old thermostats moldering in a back room somewhere.

  11. Ben says:

    When I was working as a lab tech in a secondary school about ten years ago we were clearing some junk out from under a bench in a prep room when we found a large glass jam jar two-thirds full of mercury. From memory it weighed a good deal more than a pound; according to this a pound is about two tablespoons, so it must have been four or five pounds at least. Fortunately it was unbroken, and appeared to be sealed, but after spreading plenty of sulphur around we still had to find a way of ventilating the room, given that access to the outside world was via the two adjoining classrooms…

  12. Mercury is very dense, so a pound is smaller than you think. Outside of purchase at supply stores as mentioned above, older thermostats contained mercury in a glass tube, mounted on a bimettalic strip.

  13. Ru says:

    Barely related: mercury arc rectifiers, a splendid piece of equpiment for any mad scientist who'd like an ominous blue glow in his lab without all of the hazards attendant to Cherenkov radiation. Bonus madness for all long term users.


  14. cthulhu says:

    In the '80s, I was involved with some tests where we needed to transfer a bunch of current (about 30,000 amps) from a stationary fixture to a rotating test fixture. (Don't ask.) The state of the art for doing this was a mercury-wedded slip ring: two concentric cylinders with the gap between them filled with mercury. We conveniently forgot to tell the our company's safety dept about the mercury; we just way over specified the slip ring and trusted that it wouldn't blow up. Hate to think about how much mercury vapor would have been in the air had the slip ring failed...

    We did, however, put the dozen 73-farad-each PCB-filled capacitors which powered the whole thing in a sealed box in case one of them blew up when charged to 2000 volts. No sense in taking too many risks.

    • LafinJack says:

      ...30,000 amps from a stationary fixture to a rotating test fixture?

      • cthulhu says:

        The test apparatus that needed all that current (it was dumped out of the capacitor bank in a few milliseconds) had to be rotating to work, and was pretty small - say, 5 x 18 inches. Too small to contain the power generator. Hence the capacitor bank and mercury-wedded slip ring.

        • Tim says:

          In language nazi news, I'm pretty sure you mean "mercury-wetted" not "mercury-wedded".

      • nooj says:

        cthulhu said "don't ask" and you asked???

  15. apm says:

    1991, high school, organic chemistry. One class day for some reason I can't remember the teacher is having us go through the supply room behind the classroom instead of having us draw benzene ring diagrams. The most notable item discovered on the shelves: one sealed jar of asbestos.

  • Previously