Hello
in contex of "Could anybody please tell me - How many UN Listed substances in SAP EHS and what are they."
answer is like:
If you have a "fresh" EHS system never used before) then the answer is: "Zero". The database is empty and no object of type "specification" exist.
Either you create them by your own or you can buy content, BUT you should have understood the EHS standard data model before you start an EHS project
C.B.