For anyone else struggling with disappearing non-latin characters in one-byte encodings - setting LANG env var (as the manual states) does not help at all. Look at LC_ALL instead.
In my case it was set to "pl_PL.utf8" but since my input file was in CP1250 most of polish characters (but not all of them!) had gone missing and city of "Łódź" had become just "dź". I've "fixed" it with "pl_PL".