Agreement with inequality axioms and perceptions of inequality among environmental justice and risk assessment professionals

Quantitative measures of inequality are commonly used when evaluating income inequality and have gained increasing importance in evaluating distributions of environmental and other health risks. However, there have been few attempts to determine whether the theoretical underpinnings of these measures are supported empirically, especially among individuals who may be end users of the information, and whether considerations differ for health risks and income. In this study, we administered surveys to 160 environmental justice and risk assessment professionals to identify adherence to standard inequality axioms for questions framed around both health and income. To better understand beliefs and relative priorities placed on inequality, we also assessed preferences for utilitarian, egalitarian or prioritarian methods of resource distribution, and willingness to trade efficiency for equality. A majority of respondents did not support key axioms that underlie common inequality indicators, believing that uniform proportional increases in income or health would increase inequality and rejecting the Pigou-Dalton transfer principle (which states that inequality should decrease when transfers are made from a better-off to a worse-off person) under certain circumstances. Environmental justice professionals had significantly stronger egalitarianism preferences than risk assessment professionals (p = 0.02), while respondents expressed greater utilitarian tendencies when questions were framed as health rather than income inequality (p = 0.08). Our findings indicate that concepts of inequality may not be aligned with commonly utilised quantitative indicators and that different stakeholders may perceive inequality differently, emphasizing the need for explicit communication about the interpretation of quantitative inequality measures in health risk assessment.