An Aggregate Public Health Indicator to Measure, Compare and Evaluate the Impact of Environmental Exposures. A. E. M. de Hollander, J. M. Melse, E. Lebret, and P. G. N. Kramers, National Institute of Public Health and the Environment, Bilthoven, The Netherlands
The impact of hazardous environmental exposures may take many shapes of various severity and clinical significance, ranging from slight reversible lung function deficits to premature death. Most available risk measures fail to address this variety, as they often predominantly relate to probability rather than the nature and magnitude of adverse health consequences. In many approaches for risk management the concept of health risk is, for practical purposes, narrowed to mortality risk. In this paper a framework is presented to aggregate divergent environmental health impacts associated with different types of environmental exposures, such as air pollution, residential noise and technological risk. From the policy maker’s point of view there are at least three good reasons for this type of aggregation:
- risk comparison (how bad is it from a public health perspective?)
- assessing the effectiveness of risk reducing measures (how much health is there to be gained?)
- characterizing health risk accumulation associated with simultaneous environmental exposures.
The approach is based on an impact measure that aggregates three important dimensions of public health: life expectancy (‘quantity of life’), quality of life, and social magnitude. Healthy life expectancy is either lost by premature death, or by loss of quality of life, measured as discounted life-years within a population. Of course, attributing quality discounts associated with certain environmental health effects is value-laden and thus potentially controversial. Therefore, the use of transparent, appealing criteria is required. In this paper, an assessment of health loss associated with simultaneous environmental exposures will be presented.