Kraft pulp and paper mills do have a characteristic smell. This happens because during the pulp making process, wood is decomposed through boiling and the use of chemicals, which releases an odorous, but harmless organic Sulphur gas known as mercaptan and other reduced Sulphur compounds.
That’s the reason behind the strong smell. This gas is produced in very low concentrations and is not harmful in any way.
“…DURING THE PULP MAKING PROCESS, WOOD IS DECOMPOSED THROUGH BOILING AND THE USE OF CHEMICALS”