There are three hidden characters created at the front of the first record when I use the TOAD Export Flat File feature from the editor data grid.
Export is being done using UTF-8 encoding.
Change the encoding to ANSI when exporting. You can set this in the same screen you specify the path and name of the file you are exporting. You need to click the (...) button, to browse, and it will give you the option and the bottom of the save window.