sulfur smell from somewhere. is it dangerous? how to find it.

February 11, 2008 5:31 AM

sulfur smell from somewhere. is it dangerous? how to find it.

Background info: I live on the top floor of a 4 story building. My water heater has no tank. My neighbor has a cat (pee?). Sometimes a sulfury smell comes from the sink but it is distinctly different. The smell mostly comes at night. The floor is tatami. The apartment has been renovated (possible drain somewhere in the floor?). The sink in the kitchen has no trap, just a straight pipe. This is Japan. The smell is sulfury with a little rancid oil note, quite dull but lingering. It only smells in the bedroom. It definitely comes from the right, the direction of my neighbor's apartment.

I googled but all the pages seemed to deal with a smell in drinking water. It seems to come from the floor but maybe the wall. I don't think it's based on water directly, it seems to come in puffs.

Any ideas on how to pinpoint the source? Is it possibly dangerous?

posted by Infernarl to home & garden (5 comments total)

Some type of bacteria living in the sink drain are probably the source of the sulfur smell. Our bathroom sink occasionally does this. It isn't (or shouldn't be) dangerous, but it is time to give the sink drain a cleaning. Standard drain cleaner should work fine (Drano or the equivalent). It can be maddeningly hard to pinpoint the where the odor originates as your nose will often become acclimated to it before you locate it, but the sink drain is a likely source.

Your sink does have a trap, I'm sure - just not where you can get at it. A sink with no trap at all would allow sewer gas up into your living space.
posted by caution live frogs at 6:02 AM on February 11

"sulfury" as in rotten eggs?

Could be the neighbor is a cabbage/kale/broccoli lover and cooker, or some bacteria decomposing organic matter somewhere in the sink pipes.

Dangerous: not. The most poisonous sulphur compound is probably H₂S, or hydrogen sulphide, but it's so awfully smelling (of rotten eggs) that you can smell it at concentrations about 5,000 times lower than it actually even gives you some eye irritation.

I'd suggest introducing the trap to the japanese sink, and see how they get along.
posted by _dario at 6:06 AM on February 11

rotten egg (sulphurish) smell can mean the odorant they add to natural gas so you know if you have a leak. I am ignorant to the heating methods used in japan, so it is highly likely that is irrelevant, but if you do have natural gas heat, you may look into it.
posted by domino at 6:14 AM on February 11

Yeah, please try to narrow down the type of sulfur odor. All the really fashionable foul smells are sulfury to one extent or another.

You mention the rancid oil note, and that does sound a bit like drain smell. I would describe cat pee as more of an acrid smell.

One way to see if it is the smell comes from the drain is to stop up the drain and fill it with water. And see if it occurs then.

Does the smell only happen when you run the water for the first few seconds? Probably gunk in the faucet valving.

If you have a gas cooker, turn it on briefly without lighting it and give it a smell. The odorants they use do change from time to time. If the smell is gas, you'll want to get it fixed. But the level of gas required to cause imminent danger is enough that you'd KNOW it. Very eye wateringly stinky.
posted by gjc at 7:58 AM on February 11

You might call the local gas company and have one of their technicians come out with a super duper sniffer to make sure it's not a low pressure gas leak. The visit for this is no charge and they will come out 24/7. They do know that there are many different odors people think might be gas leaks and take all reports seriously. Do it as a safety precaution if nothing else.
posted by ptm at 11:29 PM on February 11