INTEGRATION OF QUALITATIVE AND QUANTITATIVE INDICATORS IN COMPARATIVE RISK ASSESSMENT

摘要

The term risk is understood in rather different ways by the public and by scientists, and it has therefore proved difficult to evolve a framework for integrating qualitative and quantitative aspects of risk assessment. Considerable advance has been made in the analysis and quantification of health risks using epidemiology, test on organisms and modelling approaches to supply quantitative estimates. Comparative results have been presented as mortality or morbidity estimates, or some derivation of these, normalized for a 'unit of activity'. Approaches to the broad category of environmental risk assessment have progressed more slowly. Variation in the focus of interest on different organisms, or association of organisms, on different habitats, on physicochemical conditions or biological impacts, and a diversity of concerns about changes in structural or functional attributes, have all prevented a uniform approach that would enable integration and the formulation of comparative assessments. Some progress has been made through the use of a conceptual framework centred around the pressure - state - impacts - response approach. However, certain of these elements still require a method for integrating qualitative and quantitative aspects. A number of methods have been proposed; these include ranked assessments, emission or ambient quality values and transgression of critical loads or critical levels. There are also a number of management based approaches spanning relevancy to sector, industry, process, product and customer concerns. These approaches centre mainly around life cycle assessment. Future research has to focus not only on how integration might be achieved but also on how such integration will be able to facilitate comparative environmental risk assessments.