How to get the 2nd column value of dropdown list.

How to get the 2nd column value of dropdown list.

Hi,
I need your help because I want to get the value of the second column of  dropdown list.
I populate it when I click on the checkbox in this way:
var chk = $("#chk"+arg2).is(':checked');   
    if(chk == true)
    {
        $("#codiciGiusti").append('<option value="' + arg1 + '">' + arg1 +' '+ dataAssenza +'</option>');
    }else{
        $("#codiciGiusti option[value='" + arg1 + "']").remove();
    }

and it works fine.

My problem is how to get the second column value (dataAssenza) from it.

Thanks in advance.

Tegatti