Yes, it is possible. You can put any code into a trigger procedure that you can put in any other procedure.
But - I would not recommend you to do so. Usually one tries to get the best read performance out of an application. You do so by avoiding as much i/o on the database as possible and and have the operations as atomic as possible. If you update something in a FIND trigger, you are not even bouncing back and forth between the database engine and the ABL execution layer ( triggers are executed in the ABL execution layer in the client context and _NOT_ in the database engine ) for each record you retrieve for such a table, additonally you modify buffers in the shared memory which need to be written back to disk plus all the transaction overhead that the server does to make sure your data does not get corrupted.
Again, you can do that, but from a performance perspective this IS THE WORST CASE SCENARIO that one can think of when it comes to read performance. If you really must implement auditing on retrieval of record from certain tables you should look into the auditing functionality that is built into the database engine since OpenEdge 10.1A. This is because it is optimized to get the best possible peformance. And, as a bonus, you don't need to change any code in your application.
Heavy Regards, RealHeavyDude.