If your application was developed correctly, it will use the DBMS_APPLICATION_INFO package to set the MODULE and ACTION columns in V$SESSION. This would help you correctly diagnose where the SQL statement originated from. Unfortunately, most applications do not make use of this package like they should.
If the code was from a stored procedure, trigger, etc. then you can query DBA_SOURCE similar to the following:
SELECT owner,name FROM dba_source WHERE UPPER(text) LIKE UPPER(%If the SQL statement originated from the application, then you'll have to talk with the application developer or vendor.
This was first published in April 2006