Mahabharat, Vana parva, tirtha-yatra parva https://www.wisdomlib.org/hinduism/book/the-mahabharata-third-book/d/doc7362.html. Says:
One should next proceed to the excellent tirtha of Brahma. Bathing there, a person, of the (three) inferior orders, obtaineth the status of a Brahmana, and if one be a Brahmana, his soul being purified from every sin, he attaineth to the highest state.
Do any other scriptures mention this particular property of brahma tirtha?