Email Library Constructor

Having trouble with this, maybe someone can help.

I have a Library that handles on my email functions.  I have 3 environments setup.  Development, Test & Production.  What I am trying to do is have different application names and mailto addresses depending on the environment.  I've tried to do this through constructor but no luck.  Basically, I don't want test emails going to real users and I'd like to better distinguish what is test from what is actual data for my testers who are also users...

PHP Code:

public function __construct()
    {
        parent::__construct();
 $this->load->library('email');

if(ENVIRONMENT == 'development')
 {
 $emailto = 'developer@email';
 $appname = '***DEVELOPMENT APP***';
 }
 elseif(ENVIRONMENT == 'testing')
 {
 $emailto = 'test@email';
                        $appname = '*TEST APP*';
 }
 elseif(ENVIRONMENT == 'production')
 {
 $emailto = 'dynamic@email';
                        $appname = 'LIVE APP';
 }
    }

public function email()
 {
 $message = 'Email Message.';

 $this->email->from($XXX, 'XXX');
 $this->email->to($emailto);
 $this->email->subject($appname.' -> Email Subject');
 $this->email->message($message);
 $this->email->send();
 } 


I can get this to work if I put the code directly in each function but it would be so much nicer if it could just all be in one spot!!

Sorry for any formatting problems, I am not a forum pro...  THANK YOU.