Hi, we are experts in email bulk marketing. We will send the 48,000 emails for you and send detailed report on the bounced back due to no longer in use. We assure you that 100% of the emails will land on receivers' inbox and not spam/junk folder. We never use the email list provided by you for any other purpose other than what is specified by you. If you are still unsure about this, you can get us to sign a non-disclosure agreement. You can see our profile at www.freelancer.com/u/w6d.html. Please drop a message and we can chat.