Almost four decades ago, SCOPE, the Scientific Committee on Problems of the Environment, launched a major programme on the biogeochemical cycles of the main elements. Over the years, projects—often developed jointly with UNEP—focussed on the study of carbon, nitrogen, sulphur and phosphorus as well as some of the trace elements (lead, cadmium, mercury and arsenic) and their effects on the food chain, resulting in 17 SCOPE monographs and a number of proceedings volumes.