Why income inequality indexes do not apply to health risks.

Several recent papers have sought to apply inequality measures from economics, such as the Atkinson Index (AI) for inequality of income distributions, to compare the risk inequality of different mortality risk distributions in an effort to help promote efficiency and environmental justice in pollution-reducing interventions. Closer analysis suggests that such applications are neither logically coherent nor necessarily ethically desirable. Risk inequality comparisons should be based on axioms that apply to probabilistic risks, and should consider the multidimensional and time-varying nature of individual and community risks in order to increase efficiency and justice over time and generations. In light of the limitations of the AI applied to mortality risk distributions, it has not been demonstrated to have ethical or practical value in helping policymakers to identify air pollution management interventions that reduce (or minimize) risk and risk inequity.