One constituent of cycad seeds was cycasin, a glycoside which had been isolated in the 1950s, and this was now reported to have a remarkable range of toxic effects. Large doses caused death from acute liver failure; smaller doses might be tolerated by the liver, but later gave rise to a variety of cancers. While cycasin did not seem to be toxic to adult nerve cells, it was one of the most potent carcinogens known.
