Introduction

In order to better understand the potential impact of global environmental change on human health it is necessary to accomplish two contrasting tasks. First, it is important to widen the conceptual structure by which health risks are evaluated to include a broader array of more distal risk factors than has been common in public health in recent years. In addition, to focus the analysis in terms that facilitate meaningful comparisons with other important risks to health, there is need to structure the analysis in absolute measures of ill-health and in terms of standard and emerging decision-making tools. Progress in both these arenas will be needed to effectively guide intervention policies.

To approach these tasks, we follow a temporal progression. First, we briefly examine historical views of human health and the environment to show that the challenges now created by global environmental change actually extend contemporary public health's scope into realms previously embraced by the field. We next offer an analytical structure for addressing the linkages and pathways between multiple social and ecological processes acting at various scales, ultimately influencing health. Issues of causality and capability lead us to examine how a disease-based, resource-effectiveness paradigm might be expanded to understand environment–health connections today. We quantify the current contribution of environmental risk factors to ill-health, and from this basis peer into the future. We discuss how attributable and avoidable risk calculations relate to public health planning, and the implications of incorporating considerations of net present value and sustainability.