Naphthalene is the active chemical in mothballs that releases a distinctive, sharp odour when the product is exposed to air. Over time, the noxious smell can permeate a house where mothballs are used extensively in clothes closets, attics and dresser doors. Ventilation is the key to getting rid of the odour, although naphthalene evaporates faster when also exposed to cold air.
Take out and dispose of all mothballs in the home. Check closet shelves, dresser drawers and boxed clothes in the attic or basement.
Move dressers outdoors to a storage shed or garage with the help of a friend. Remove the drawers and lay them down with the open side facing upward to air out the odour. This works best during winter. Check the furniture once a week to sniff and determine how the odour elimination is coming along.
Open closet doors and remove clothes to give the space room to air out. Open windows in the room with the closet and position box fans in the windowsills to blow air out of the building. In winter, it may be practical to air out only one room at a time to reduce lost heat. Closing the heater vents in the room you are working on can help with the heat bill.
Turn on attic vent motors, if you have them, to air out the space overhead. Otherwise, position a box fan facing the side of the house where vents are built into the rafters. Run an extension cord downstairs if you do not have a power outlet for the fan in your attic.
Place fans in the basement to circulate air and open all available windows.
The smell of naphthalene is tenacious and may take weeks before it is completely gone.