Abstract: The invention concerns a device for the removal of foul air from toilet bowls or the like. The device comprises a conduit having an inlet opening and at least one outlet opening spaced from the inlet opening. The conduit has a hook shape and is capable of hooking over the rim of the toilet bowl and under the seat so that the inlet opening is within the bowl and the outlet opening is outside the bowl. The device also includes an air treatment means within the conduit, capable of improving the quality of foul air passing through it. The device also includes a battery-operable fan capable of drawing foul air out of the bowl via the inlet opening, along the conduit, through the air treatment means and out of the outlet opening. The air treatment means, optionally together with the battery, may be provided as a replaceable pack. A securing means, e.g. in the form of a strap, may pass through the device and be of a length to fit around the bowl. A lock can be provided on the strap.