Basement Bathroom Stink Pipe

We had a bathroom installed in our basement. We have a ranch house buit in the late 60's. The plumber installed a stink pipe in the wall which is causing odor in the basement. The pipe is not vented to the outside. What can I do to stop the odor. thanks.

The vent pipe needs to go outside, and should go up to the roof or tie into the rest of the existing vent system.

we don't have much info ,butif you don,t use these

fixtures for a long time,the trape water may have dried up! run some water down each drain. if the oder is still there,you have a health problem.

have a REAL plumber look at this.

They could have also installed an air admittence valve instead of running a normal vent line. This relies on a rubber membrane and vacuum to admit air so that the traps aren't siphoned dry. If the rubber has degenerated and is leaking, that could be the cause of the smell. How old it the installation? Bleach smell from a nearby laundry can accellerate the degeneration of the rubber on an AAV.