E-mail to contact list automatically as BCC

Is there any possibility to tell a contact list to place itself in the bcc field by default when “Send message…” is clicked in the right-click popup menu? (In addition with a self-copy automatically in the to-field?) And if not: That would be a helpful feature. I have such a contact list (yearly updated) with private e-mail-addresses and it has happend twice so far that i’ve  sent out a message with all contacts readable for all in the to field. Thank you.

Have you tries entering the contact list in the automatic bcc: option?
menu/tools/accounts/general