how to add config array variable data to bcc email in codeigniter

 $config['bcc_emails'] = array('xy@gmail.com','xy12@gmail.com');

$bcc_emails=$this->config->item('bcc_emails');
$this->email->bcc($bcc_emails);

or

$this->email->bcc(array('xy@gmail.com','xy12@gmail.com'));