It could be many things without being able to hear the noise first hand it is difficult to guess. Look for the obvious first does the wheel make contact with the inner fender liner or is there any marks within the wheel well area like something has been touching or dragging, broken or come loose. Look at the CV joint boot is it in tact, look at the sway bar link end is it attached at both ends. Inspect the wheel is tight and inspect for play in the ball joint, tie rod end and suspension bushings.
I had a similar problem on a Dodge Caravan and it turned out to be the wheel hub (wheel bearing) which was worn. Turning right pushes the weight of the car against the hub, silencing it almost completely while turning left removes most of the strain, bringing the noise back. A simple check is to jack up the car and turn the wheel by hand. If the bearing is the problem you will hear it grinding.