In the early Song dynasty, followers of this Taoist idea (chiefly the elite and upper class) would ingest mercuric sulfide, which, though tolerable in low levels, led many to suicide.
ɪnðɪ ˈɜːli sˈɔŋ dˈaɪnɐsti, fˈɑːloʊɚz ʌv ðɪs tˈaʊɪst aɪdˈiə tʃˈiːfli ðɪ ɪlˈiːt ænd ˌʌpɚ klˈæs wʊd ɪndʒˈɛst mɜːkjˈʊɹɹɪk sˈʌlfaɪd, wˈɪtʃ, ðˌoʊ tˈɑːlɚɹəbəl ɪn lˈoʊ lˈɛvəlz, lˈɛd mˈɛni tə sˈuːɪsˌaɪd.