I expect you know something about MySQL! So this is just the important part :
<?php
$emailfile = '~/passwords.list';
$data = file($emailfile);
// connect to DB here
while(list($index, $value) = each($data)) {
$sql = "INSERT INTO emails SET email='$value'";
// fire sql here
}
// close connection to DB here
?>
Hint : The WHILE-loop is just one way of traversing the data-array.