How to redirect bounced emails to /dev/null instead of moderator ?

At times, subscribers in my mailing list have their quota full (or their mail server is down, etc. etc.) and as a result, postings to their addresses bounce. All these bounced emails are then coming back to me since I am the moderator of the list. I am managing three moderated lists, each having 1000+ subscribers and so, these bounced emails are turning out to be quite overwhelming.

Is there a way to redirect these bounced emails to /dev/null instead of moderator ?

Thanks
Nishi