Dynamically add BCC to selected recipient

I have a contact form set up with an option for the user to select from multiple recipients. Here is the code:

<p>Which department would you like to contact?<br>
[select* department include_blank "Department 1|dept1@email.com" "Department 2|dept2@email.com" "Department 3|dept3@email.com"]
</p>

I’d like to add a BCC address along with the address listed for a specific selection. I know CF7 supports multiple emails by separating them by a comma, but how would I identify one as BCC?

I’ve tried the following with no luck:

"Department 3|dept3@email.com,Bcc: sample@email.com"

"Department 3|dept3@email.com?bcc:sample@email.com"

Thank you.

https://wordpress.org/plugins/contact-form-7/