Hi,
Unfortunately there is no way as of now by which we can know the current isolation level in DB2.
There has been a lot of discussion on this thread and I would advise you to search the archives for a lot of information on the same, especially posts from other members on this topic are really great.
Please also make it a habit for posting your database level, i mean version and fixpack and the Operating System with everypost. That will make it easier for everyone to get a better hang of your scenario.