public function setRecipients($email)
    {
        if (!is_array($email)) {
            $email = explode(',', $email);
            // trim all values
            array_walk($email, function(&$val) {
                return $val = trim($val);
            });
            // remove empty elements
            $email = array_filter($email);
        }

        foreach ($email as $e) {
            if (!$this->validateHeaderFieldValue($e)) {
                throw new EmailValidationException(__('Recipient address can not contain carriage return or newlines.'));
            }
        }

        $this->_recipients = $email;
    }