Negative pressure is: (a) applied through a shallow manifold inlet fitted between the rear of a toilet porcelain bowl and hinged seat; (b) created by a remote blower; (c) conveyed via conduit. An adjustable hood in front of the manifold optimizes odor collection. The blower can be located in a housing possessing multiple inlet ports for connection to a plurality of manifolds. The blower can also be used in line with conduit and multiple blowers utilized. A sensor port in a manifold extension facilitates empirical verification of air flow. Electrical supply to the blower can be controlled by a light switch: (a) independently; or with: (b) a vent that can be exhausted through the same conduit, or (c) a humidity blower. Plastic and metal conduit of differing cross section are joined with an adapter and either connected to a blower housing inlet port. PVC conduit is disposed within wall frames hung from the sill.