Special Paper 155 includes the published papers presented at the symposium on “Trace Element Geochemistry in Health and Disease” held at the Annual Meeting of the Geological Society of America, Minneapolis, Minnesota, November 15, 1972, under the sponsorship of the Joint Technical Paper Committee of the Geological Society of America and the National Association of Geology Teachers. The first symposium on “Environmental Geochemistry in Relation to Human Health and Disease” was held in 1968 in Dallas, Texas, at the annual meeting of the American Association for the Advancement of Science and is published in Memoir 123 (1971) of the Geological Society of America.

One paper presented at the symposium in Minneapolis, “The Chemical Behavior of Major and Minor Elements in Aquatic Environments at the Earth’s Surface” by R. C. Reynolds, is not included in Special Paper 155; an additional paper, “Some Possible Relationships of Water and Soil Chemistry to Cardiovascular Diseases in Indiana” by R. W. Klusman and H. I. Sauer, is included.

Among others, the following symposia and conferences on trace elements and health have contributed additional data: Trace Substances in Environmental Health, I–VIII, D. D. Hemphill, editor, 1968 to 1975, proceedings of the annual conferences of the University of Missouri; Trace Element Metabolism in Animals (TEMA)—I, edited by C. F. Mills and published by E. and S. Livingstone, Edinburgh and London, 1970; TEMA—II, edited by W. G. Hoekstra and others, held in Madison, Wisconsin, and sponsored by the University of Wisconsin Madison and the United . . .