Prioritizing ecological and human welfare risks from environmental stresses

The ecological systems of Earth are subjected to a wide array of environmental stresses resulting from human activities. The development of appropriate environmental protection and management policies and the appropriate allocation of resources across environmental stresses require a systematic evaluation of relative risks. The data and methodologies for comprehensive ecological risk assessment do not exist, yet we do have considerable understanding of econological stress-response relationships. A methodology is presented to utilize present knowledge for assignment of relative risks to ecological systems and human welfare from anthropogenic stresses. The resultant priorities, developed for the US Environmental Protection Agency's (EPA) relative risk reduction project, highlight global climate change, habitat alteration, stratospheric ozone depletion, and species depletion as the highest environmental risks, significantly diverging from the present emphasis by EPA and the public on toxic chemical issues. Enhanced attention to ecological issues by EPA and development of ecological risk assessment methodologies that value ecological and economic issues equitably are key recommendations.