$str = '6085,6084,6083,6082';
$split = explode(',',$str);
That will split the $str string into an array containing those elements.
Ex.
$split[0] = 6085
$split[1] = 6084
ect...
As far as looping it into a MySQL script, it depends on what your script is doing and how your going to handle the data. That should be a good start to what you want to do though.
P.S. There are several other ways to do it, this is just one way to skin that cat.
P.S.S. You can refer to this website for more information on the explode function
