php var_dump(1) returns string(4)

I am parsing a text file using PHP and one of the lines contains simple numeric characters. However, I came across a file that for some reason contains other "hidden" characters as part of this number.

I came upon this thread php var_dump(); result php string(4) "1" which hints that there might be multibyte characters but there is no solution.

Debugging

echo 'line:' . $line . '<br/><br/>';
var_dump($line);
var_dump(ord($line).'|'.ord('1').'|');
var_dump(chr(ord($line)));

Here's the output

line:1
string(4) "1" string(7) "239|49|" string(1) "�"

Is there a good PHP solution that would help eliminate random junk characters in a string?