Our house is 50 years old - built on a slab. There is a musty/earthy odor under the kitchen sink and in the adjoining cabinets. The cabinets back up to the wall between the kitchen and the bathroom. We do not have a garbage disposal.

My husband thinks the odor comes actually from the space from under the tub. This is worse during the spring and summer months than in the winter. We notice the same odor when the air-conditioning is on for the first time in the summer. Around the pipe that comes up under the sink to the drain, there is an opening of about 2 inches and I can definitely can smell this earth smell there. To further explain the smell, it smells like potatoes before they are peeled. Definitely earthy. My plan is to somehow cover/close off that area to see if that makes a difference. I have used jars of Natural Magic odor absorbing gel in those area with a little success.

Any suggestions would certainly be welcome. I've read through all the hints on this issue but none seem to match my "earthly" problem!