I have one loop operational and then was out of the hobby for 17 years. The sun shone in a window on my layout and the ties are much lighter than new Gargraves. They also look more natural and real than the dark new ties. So I put some bleach in a small container and wiped the bleach on the new track ties with a cloth. Wipe off the rails with a clean cloth and set the track in the sun to dry.
Dennis San Fernando Valley CA.