Cleaning up the mercury from a broken thermometer...

October 14, 2013 1:10 PM

I broke a thermometer by knocking over the container it was sitting in. That container was filled with a pretty acidic solution (~ph 3). There are no visible mercury pools or droplets. I put on gloves and sopped up the liquid, which was probably not the best idea, but I was worried about my kid. Short of hiring an expert cleaner, which I am willing to do if necessary, what should I do now. Cleanup sites tend to assume that the mercury is the only liquid present, and I'm not sure how breaking into the acid might affect things.
posted by OmieWise to Science & Nature (14 answers total)

What was the acid? Mercury doesn't react with most acids but can with solutions of nitric or sulfuric.

If it was all contained in that one container I would slap a lid on it and dispose of it in the hazardous waste disposal (assuming this is home and not lab based most communities have hazardous waste collections sites/days. Call your version of the non-emergency number (usually 311) to find out.
posted by Captain_Science at 1:17 PM on October 14, 2013

Response by poster: It was StarSan: Dodecylbenzenesulfonic Acid - 300ppm and Phosphoric Acid - 780ppm. Everything hit the floor and was all over the floor.
posted by OmieWise at 1:20 PM on October 14, 2013

How old is the thermometer? Many are no longer mercury.
posted by kellyblah at 1:25 PM on October 14, 2013 [1 favorite]

I'd call the non-emergency fire department number and ask them.
posted by Ruthless Bunny at 1:44 PM on October 14, 2013

In the US, poison control is better than the fire department for household mercury spills.
posted by ryanrs at 1:46 PM on October 14, 2013

Mercury tends to roll up into little balls when it is dropped. It is hard to mistake its liquid silver appearance. Since it has been banned from home instruments for many years, it is unlikely that your substance was mercury although it might contain mercury. Sneaky children played with mercury in the good old days; they survived.
posted by Cranberry at 1:52 PM on October 14, 2013 [4 favorites]

Elemental mercury is only very sparingly soluble in water. If any mercury was released, you would see it balling up in droplets, even in the StarSan solution. Where did the thermometer break? Is the bulb still intact? Is it possible no mercury was released?
posted by mr_roboto at 2:13 PM on October 14, 2013

Response by poster: After looking at the remains of the thermometer, I think that there was no or very very little mercury released. I packaged up all the sopping rags, I'm airing out the room, I've got a floor heater on as instructed by the EPA, and I think that will handle it. I never saw any mercury, even looking with a flashlight. Thanks for all the answers.
posted by OmieWise at 2:18 PM on October 14, 2013

Out of an abundance of caution, I would also put a fan in a window and exhaust some air out for a while. On the off chance that some mercury got aerosolized into the air. It's pretty doubtful, but it might at the very least help you feel better about having done everything you could to limit risk.
posted by gjc at 2:58 PM on October 14, 2013

OmieWise: "I never saw any mercury, even looking with a flashlight."

Then it's fairly safe to say there never was any mercury.

Mercury is not highly reactive at room temperature*. There would be some elemental mercury present after a spill.
posted by IAmBroom at 3:02 PM on October 14, 2013 [1 favorite]

I worked in a lab many years ago where there was the occasional mercury spill. We would clean up what we could and then douse the area with sulfur powder. Sulfur reacts with mercury, so that it no longer vaporizes. One of the problems with mercury is that it releases mercury vapor over time. This page looks like it might be a good summary.
posted by DarkForest at 4:24 PM on October 14, 2013

But note that sulfur is rather stinky, and I don't know how easy it would be clean it out of a rug if you decide to use it.
posted by DarkForest at 4:31 PM on October 14, 2013

If it were in an actual chemistry lab (guessing not seeing as you are worried about 300 ppm and 800 ppm concentrations of acids) I would have soaked up the liquids with paper towels and then sprinkled the area with some sulphur. A thermometer isn't a large amount of mercury and it reacts quite readily with sulphur to form a complex that allows it to be swept up readily. I would then sweep everything up and put it into an old plastic reagent bottle (a big one like mag sulphate so it can all fit) and label it as mercury waste and send it off for disposal with the waste guy. It will get burnt and then the gasses scrubbed to remove the mercury from the flue gas. Everyone has such a conniption over elemental mercury and that is actually not that dangerous. The danger is if it gets into the environment and settles into an environment condusive for generating alkylmercuries, which are actually quite bad. The suplhur as well will not be stinky as it is the volatile sulphur compounds that are stinky and not elemental sulphur, if you washed the area in ethanethiol it would also work to clear up the traces of mercury but you lab mates will kill you. Solid yellow sulphur on the other hand is fine so long as you don't burn it.
posted by koolkat at 2:20 AM on October 15, 2013

Response by poster: (guessing not seeing as you are worried about 300 ppm and 800 ppm concentrations of acids)

Thanks. I wasn't actually at all worried about the acid. I wanted to know if the acid would change in any way how concerned or unconcerned I should be about the mercury. I listed the strength only because someone asked about it.
posted by OmieWise at 5:30 PM on October 17, 2013