text: In 1989 Harry Falk noted that, in the texts, both haoma and soma were said to enhance alertness and awareness, did not coincide with the consciousness altering effects of an entheogen, and that "there is nothing shamanistic or visionary either in early Vedic or in Old Iranian texts", Falk also asserted that the three varieties of ephedra that yield ephedrine (Ephedra gerardiana, E. major procera and E. intermedia) also have the properties attributed to haoma by the texts of the Avesta. At the conclusion of the 1999 Haoma-Soma workshop in Leiden, Jan E. M. Houben writes: "despite strong attempts to do away with ephedra by those who are eager to see sauma as a hallucinogen, its status as a serious candidate for the Rigvedic Soma and Avestan Haoma still stands".
  The Soviet archeologist Viktor Sarianidi wrote that he had discovered vessels and mortars used to prepare soma in Zoroastrian temples in the Bactria–Margiana Archaeological Complex. He said that the vessels have revealed residues and seed impressions left behind during the preparation of soma. This has not been sustained by subsequent investigations. Alternatively Mark Merlin, who revisited the subject of the identity of soma more than thirty years after originally writing about it stated that there is a need of further study on links between soma and Papaver somniferum.
  According to Michael Wood, the references to immortality and light are characteristics of an entheogenic experience.