C. F. Keil and Franz Delitzsch on Leviticus 13:38-39

Lev 13:38-39 Harmless leprosy. - This broke out upon the skin of the body in בּהרת plaits, “white rings.” If these were dull or a pale white, it was the harmless bohak, ἀλφός (lxx), which did not defile, and which even the Arabs, who still call it bahak, consider harmless. It is an eruption upon the skin, appearing in somewhat elevated spots or rings of inequal sizes and a pale white colour, which do not change the hair; it causes no inconvenience, and lasts from two months to two years.