Troubleshooting a Bad Smell in Drawers

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Dead bacteria in plywood can cause a rancid odor, and a badly catalyzed finish may also produce offensive smells. March 9, 2010

Question
We had some bureau's made recently and the client called me after a week or so and said that all his clothes had a foul odor on them from the inside of the drawers. The dovetail drawers are poplar wood and the drawer bottoms are a 1/2" plywood. I am not 100% on that yet. I sanded them down and sprayed a vinyl sealer over the laquer finish that was on them and it still smells. Does anyone have any advice to correct this problem?

Forum Responses
(Finishing Forum)
From contributor A:
Not too long ago I read a post on this forum that suggested taking some cedar wood chips, stuffing them in a nylon stocking and putting them in the drawers.



From contributor M:
You can always shellac them. The shellac will block any smells.


From Gene Wengert, forum technical advisor:
The foul odor that smells like vomit is caused by a bacterial infection that developed in the tree. The bacteria created fatty acids that then turned rancid. It is seen in foreign plywood, and so it is nearly 100% that the odor is coming from the drawer bottoms. (It also occurs in oak, hemlock, and many other species. See the archives here for more info).

The odor cannot be removed as the rancid acid is within the wood. It will be more obvious in humid and closed locations. It cannot be masked with cedar chips. It cannot be encapsulated with shellac or other finishes. Unfortunately, removal is the only cure.




From contributor R:
It’s quite possible that the odor is from the materials you/your finisher applied to the drawers. If the drawers are not let to off gas they will continue to have a smell. If the drawer boxes were finished and then installed in the cabinets right away, they will continue to smell.

First off, let’s not jump to conclusions that the odor is emitting from foreign manufactured plywood. If it’s possible to remove the drawer boxes, bring them back to the shop and place a fan so as the air movement is directed towards the insides of the boxes. Right now the absolute best way to approach the removal of the odor is to get some air movement going over the boxes.

To arbitrarily construct a new box without knowing the cause of the odor would be an unnecessary waste of money if all you need is air to remedy the problem. I have finished more drawer boxes than I care to remember and I have never run into a bacterial problem in woods from another country (if you want to call worms a bacterial problem, I’ve run into many of them). The problems associated with a stinky drawer interior was usually a result of me finishing the drawers and then inserting them into their cabinets too soon after they were sprayed. Air out the drawer boxes over the weekend and see how they smell come Monday morning.



From Gene Wengert, forum technical advisor:
I do not believe that the rancid odor smell that is quite similar to a vomit smell would result from a finish. Hence, I prefaced my comments with the statement describing the odor. As a person that is called upon when there are problems, I have encountered this bacterial problem many times (plywood and lumber) and it seems that recently that has been more than usual. Foreign plywood is source quite often, usually it is inexpensive plywood. Note that moisture seems to bring out the odor, so you might also put a drawer in a humid location (home bathroom) and see what happens.


From contributor R:
All I’m saying is that if the foul odor referred to is caused by the finishing materials still gassing off, it can be resolved by air being directed, via a fan; into and onto the interiors of the guilty drawer boxes. If however, it’s found that the foul odor talked about is actually caused by bacteria. The drawer boxes should be remade and finished at no cost to the customer.


From Gene Wengert, forum technical advisor:
I agree 100% with your last posting. Regarding the smell during manufacturing, oftentimes the odor with dry wood is quite faint and well dispersed, so it is not recognized, especially with a good sander dust removal system. Once closed, the odor (both types we are talking about) can intensify.


From contributor F:
Another thing that can cause odor is when a product is over-catalyzed, it can start to leach back out to the surface of the coating. Old catalyst can smell pretty bad when they get older. If it is this, you can take one part of baking powder to ten parts of water and wipe down the re-surfaced catalyst. You may need to do this a few times until it all leaches out.


From contributor R:
Greetings again Gene. Is there any kind of checking that the Forestry Department or the Manufacturers of the plywood’s can do to prevent this bacterial infected wood from being exported to the states? It seems as if we check fruits and vegetables prior to them being allowed into our country and the Department of Fish and Game periodically checks for invading pests that might be introduced into our water ways. Are wood products subject to any kind of scrutiny? I recall years ago when Chernobal blew its stack we were concerned that the Baltic Birch plywoods might be radiated. Should we be wary of bacterial infested lumber?


From contributor S:
Ozone treatments can drastically accelerate aging of materials and cause immediately noticeable fading of colors. It also doesn't always work. There are other possible treatments besides what has already been covered depending on what the actual cause of the odor is. You have to figure out the source of the problem before you can figure out the solution.


From Gene Wengert, forum technical advisor:
The bacteria are all dead, once dried. The fatty acids remain. Hence, there is no risk to human health or to our trees.


From contributor O:
I would try the fan trick. The gasses that come out of a vinyl/lacquer finish are heavier than air and will sit in a drawer like a bowl.


From contributor P:
I would first seal the drawers with shellac as recommended. Zinsser has this statement on the third page of the document at the link below. "The unique molecular structure of shellac resin renders it impervious to odors. Just one coat applied at container consistency will completely and permanently seal any kind of odor in any porous surface. No other coating can make this claim." I knew shellac was recommended for sealing various types of odors, but that's quite a statement. It's a pretty easy solution and you can always get more aggressive if it doesn't work.


From Gene Wengert, forum technical advisor:

It is certainly worth a try, but the fatty acids are able to bleed through or exude through various coatings. They will turn a white acrylic and various other coatings dingy; conventional shellac also failed in my tests, assuming we are dealing with the bacterial issue mentioned at the beginning of these postings. Maybe Zinssers is better than before. I hope we hear from the original poster about the characteristics of the odor and the results of his tests.


From the original questioner:
Thank you all for the information and you views on this matter. I solved the problem by ordering all new drawers. I tried everything except the shellac idea. I will take one of the drawers and try it. It was definitely coming from the 1/2" drawer bottom. They did verify that it was a Russian imported plywood. I don't know, it is what it is and I hope that the next batch will be without smell!