TRACE ELEMENTS IN HEALTH AND DISEASE: Proceedings of the International Symposium on Trace Elements in Health and Disease, Espoo, Finland, June 5–8, 1990. Edited by Antero Aitio, Antti Aro, Jorma Järvisalo, and Harri Vainio. The Royal Society of Chemistry, United Kingdom, 1991. 236 pp., £45.00