This is a yes/no/maybe question. Mold in itself is not a specific violation in the property maintenance code. The code does state that all buildings/homes must be weather tight and sanitary. Mold is primarily caused by excessive moisture. This can occur as a result of rain, snow melt, leaking plumbing, humidity, shower/bath, cooking, etc. Health effects from mold range from very mild to very severe. The same mold may cause a slight irritation for one person and be deadly to another. Many factors come into play. Regardless of the type of mold in your dwelling, it needs to be eliminated and the initial cause of the mold needs to located and corrected.
Review a Center for Disease Control Mold Abatement Flyer (PDF).