Broken floating thermometer in wort- Lead? Steel?

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Feb 19, 2010
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Broke a floating thermometer in the wort. Glass is not the issue since I'm certain it will settle out and wort can be syphoned off. I can't find any info on the metal that is used to weight these and if it is harmful. There was some scorching on the bottom of the kettle we initially thought was candy sugar, but now am pretty certain it is the contents of the thermometer. Most of the metal was retrieved from the rim of the converted keg, but I am sure a bit of the metal, wax(?), and glass made it in the wort. My question is, what is this metal, and is it harmful? I would imagine lead would not be used in these thermometers since they have food applications. Steel or graphite would be likely, but I'm still not sure if this is safe. Any info would be appreciated since I would rather not dump the beer. Thanks!
Unbelievable. I did the exact same thing a week or two ago. I was pissed at myself. I pitched. Cried. Then kicked myself inna ass.
Not worth the risk, dump it.
There isn't mercury in most floating thermometers. It's usually dyed alcohol. This happened to me a little while ago and read some thread on here where someone wrote to the maker of these thermometers to ask if he should ditch his batch and the guy wrote back that the balls are steel and there is not Mercury in them so he should go ahead with the batch. I wouldn't worry about it but make sure that you strain the wort very carefully. And use a secondary fermenter, when racking into the secondary leave some beer at the top of the trub and never put the auto siphon all the way down to the trub. When I rack I am going to put something around the bottom of the auto siphon maybe cheesecloth, to catch anything that might try to get into the secondary.
That's good to know, for future knowledge. I wouldn't have hesitated to dump if it happened to me. Glad I found out before it did and I wasted a batch!
There's no mercury or lead in those thermometers. I'd be concerned about small shards of glass, so I wouldn't risk it. If you feel that you don't mind risking drinking tiny shards of glass, then don't throw it out. I personally wouldn't feel comfortable knowing that miniscule pieces of glass were in my beer, so I'd dump it.
Appreciate the responses! There is alcohol rather than mercury in most "dairy" thermometers, probably for the same reason they don't use lead. I know this thread made me feel a little better about this, so I hope it's helpful to others. Thanks again.
Not worth the risk if you ask me. Dump it. If it has mercury, you may poison yourself or your buddies. If you mess up with the siphoning, you could be drinking tiny bits of glass that will cut your insides and be very painful. My mom's dog died from eating something with glass in it.
Even if it said on the package it doesn't have mercury, I would still pitch the batch just in case. I bet the thermometer was made in China, so who knows what's in it...

These are FOOD GRADE Thermometers. and do not contain anything deadly.
They have a red stripe, and are filled with dyed alcohol. Silver=mercury.
The weight balls are steel. Use a magnet if you want to.

This just happened to my last batch. I just whirlpooled it and got all the junk (teeny tiny pile) in a cone in the center, and was able to syphon/rack to my fermenter leaving it behind. I'm even done drinking it all and I'm still alive.
Beer came out fine. No off flavors and no glass. Did a secondary to dry hop and syphoned to a corny and no glass was transferred through either syphon. No worries. Good thread though.
As has been said a a few times already, there is no mercury in those thermometers, it's a dyed alcohol. Both the glass bits and steel beads are signifigantly more dense than the yeast cake or break material. Both will settle out to the bottom of the trub..where even your siphon won't be picking it up.

I know this from experience. ;)
I used a floating thermometer for my first batch, and got rid of it right after that to prevent something like this. ;) Now I only use it to monitor the temp of water.

Glad to hear your beer turned out fine! :)
Gravity being what it is and all it would be nearly impossible to get glass in a beer this way unless you were really trying too. That being said swallowing some glass isn't really nearly as dangerous as you think. My son ate half a glass ornament from the Christmas tree and everything we found said don't worry. Sure enough he's still with us. Your insides are pretty tough and even if they do get cut they heal really quick. The piece of glass you would unknowingly swallow would be pretty damn small too so it would probably go straight through without you even knowing.
WHEW! I'm glad I found this forum. I too had my thermometer break in the last part of the brew. I didn't notice it till I was cleaning the next day and found the balls in the bottom of the brew pot. I was very close to dumping it but I won't now.
Lol, dave that's funny...I was a kid that ate half a glass ornament....and my dad's name is dave.... Are you my dad?!
This very same thing happened to me a couple months ago. I finally finished the keg last week and had no ill side effects. Like anyone, though, I did the research on my floating thermometer to make sure it didn't contain mercury or any other toxins. The lead balls sunk to the bottom (if any got out), and I accounted for about all of the glass.
Yeah, the glass seems like the main concern. Glass can break into incredibly small pieces, but they can wreak havoc on your body.

Ever had a tiny sliver of glass stuck in your foot or hand, and the only way you could tell was the light reflecting, or feel the scrapping of it against the tweezers? It will be the same thing, and since the glass is so small it may pass through almost any filter. Even if it's just one piece of glass in the wort, that will be a pain in the ASS if it gets swallowed.

Might want to just RDWHAHB and dump it. Dont lose anymore time/money on it.

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