The mold and the frogs nose. Many tanks mold as part of the cycling process, Misting the mold a few times a day with RO or Distilled water can usually fight back some of the molding process.

Usually this mold is only a light thin white covering on wood type items. I don't think it would transfer to the frogs face though. I could be wrong.

The stuff coming off the nose should be shed since they shed pretty regularly but pics should help with determining the problem.