I just moved into a rental house and the odor under the kitchen sink is so strong I have had a headache with intermittent nausea ever since I moved in (Four days ago). My landlord sealed up the hole where the plumbing goes to the dishwasher and other than that has no ideas. It is ONLY under the sink and there are no obvious wet spots or leaks. It smells kind of like a chemical/rotting combination. PLEASE suggest something !