Unregulated Pollutants (not covered by European Directives) are pollutants specific to industrial activity within the cross-border area. The common limit values at the level of Romanian – Bulgarian border have been established within the Phare Project CBC 2003 „ Development of an Air Quality Management Program for the Romanian Region along the Bulgarian Border, on the Lower Danube”.

The unregulated pollutants specific to industrial activity within the cross-border area:

   1. Hydrogen sulfide (H₂S)

   2. Ammonia  (NH₃)

   3. Carbon disulfide  (CS₂)