οὐκ ἔστι γῆρας τοῦδε τοῦ μιάσματος → that pollution never wears out, that pollution can never grow old
ἑνός: ὁ, λέγεται ὅτι εἶναι = τῷ Λατ. annus, ἔτος, ἐντεῦθεν ἐνιαυτός, δίενος, τρίενος, ὡς τὰ biennis, triennis, κτλ.· πρβλ. ἄφενος.