Find when Oracle 10g table was last populated
Have a look at the TIMESTAMP column of the ALL_TAB_MODIFICATIONS. http://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_2097.htm

Also, keep in mind this part:


  Note: These views are populated only for tables with the MONITORING
  attribute. They are intended for statistics collection over a long
  period of time. For performance reasons, the Oracle Database does not
  populate these views immediately when the actual modifications occur.
  Run the FLUSH_DATABASE_MONITORING_INFO procedure in the DIMS_STATS
  PL/SQL package to populate these views with the latest information.
  The ANALYZE_ANY system privilege is required to run this procedure.