Nope. Parity bits aren't used to detect bitrot. If you get a URE when you go to read, the parity bits will be used to get you data. If you read successfully, nothing happens at all. If you scrub, and the data is found to be inconsistent, md assumes that the parity is wrong and overwrites it.
https://linux.die.net/man/4/md
>If a read error is detected during this process, the normal read-error handling causes correct data to be found from other devices and to be written back to the faulty device. In many case this will effectively fix the bad block.
>If all blocks read successfully but are found to not be consistent, then this is regarded as a mismatch.
>If check was used, then no action is taken to handle the mismatch, it is simply recorded. If repair was used, then a mismatch will be repaired in the same way that resync repairs arrays. For RAID5/RAID6 new parity blocks are written. For RAID1/RAID10, all but one block are overwritten with the content of that one block.