About 2 weeks ago I noticed a real fine brown dust in the cabinet, under the sink in the bathroom. If you run your finger through it it kind of resembles soot. I cleaned it all up but noticed a few days ago that it's back! I have no idea as to what could be causing this. It literally looks like a giant dust ball has exploded in my cabinet. Someone mentioned purging pipelines but I can't find anything about dust being a result of it. Others have suggested termites or other kinds of bugs but I just don't see how it could be. With the way everything is evenly coated it looks like it would be coming from the top of the cabinet, but the only think above all the dust covered things are pipes and a sink. I am really at a loss as to what to do about this. I am really tired of cleaning this stuff up but, more importantly, am concerned it could lead to a much bigger problem. Please help!

Could be powder post beetles, AKA old house beetles. They leave powdery fine sawdust as they bore into wood. Looks like flour. Check for small holes. Pinhead size.

We did but no holes! Thanks!

We did but no holes! Thanks!!

They are extremely fine. Put a piece of aluminum foil under the sink and see if the dust collects in spots. If it does, the issue is powder post beetles. If you use an insect spray, make sure to get the under surface covered well.

I have exactly the same problem and its driving me mad ! Everyday I am mopping my kitchen floor and the next day the same very fine brown dust is back. Seems to be more concentrated in one area of my kitchen so I moved the kick boards but all I found was more of the same. Please help before I go mad...

I have exactly the same problem and its driving me mad ! Everyday i am mopping my kitchen floor and the next day the same very fine brown dust is back. Seems to be more concentrated in one area of my kitchen so i moved the kick boards but all i found was more of the same. Please help before i go mad ...

I'm beginning to wonder if it's some kind of mold! Is it maybe an area of the kitchen where water would be? I still have no answer to my problem but if I figure something out I will be sure to let you know!

I get what your describing around my Drive. It always seemed to me like dust saturated with grease.

I get what your describing around my Drive. It always seemed to me like dust saturated with grease.
Around my stove

I have to go with bugs. Powder post OR termites, unfortunately. Termites are your biggest worry. Often you don't find them until you take a wall down, and they have turned all the studs into powder.
If your bathroom is on the ground level and you have a basement, go look down there and answer back. Bugs usually start at the first floor but not always. I had powder post beetles on a second floor once, because of water backing up at the end of the gutter right outside that part of the house. They turned a solid oak floor into dust from underneath, leaving a paper thin top layer, so I didn't even know until I stepped on it.

Do you have kickboard vents for heating or cooling? If so, do you burn candles? Are you using heating, or cooling when this "dust" appears? Lots of options here folks. Going to be hard to figure it out without a lot more info.

Do you have kickboard vents for heating or cooling? If so, do you burn candles? Are you using heating, or cooling when this "dust" appears? Lots of options here folks. Gonna be hard to figure it out without a lot more info.

No kickboard vents. My vents are on the ceiling and the cabinet is always closed. I very rarely burn candles. What more info do you need to figure out the problem?

Show picture of this dust.

I asked for specific info but you ignored it.

Show picture of this dust.

Will do when I get time.

I asked for specific info but you ignored it.

So sorry to ignore you! I missed where it said to get back with you. I only have 1 floor to my house. Hubby going to look under crawl space sometime. Busy, busy weekend.

Interesting, I have the same thing under my sink... we live in southern Utah, so it's very dry and hot... we had the pest guy out right away and he had no idea what was doing it... not termites which is good... I have some of the stuff to show you, but it don't know how to take a photo on this message, can I cut and paste it from my pictures you think? We found some small nail holes and caulked them, but if we stopped them in there I'm worried where else they will show up. This is the only cabinet it's in... and believe me I checked all of them in our house. And we live in a single story house, no crawl space... and I checked the outside of the house... I can't find anything. Our vents are in the ceiling and it's in our guest room bath, that we don't use that much I was lucky I found it. I can't sleep at night knowing there's something in the house, plus we're getting company soon... I need help soon!