Is income inequality harmful to the environment? The answer to this question has not reached a consensus in the literature. This study seeks to provide insight into this question by examining the influence of income inequality on the environmental Kuznets curve (EKC), i.e., the impact of income inequality on the EKC turning point. Two potential mechanisms through which inequality may affect the EKC turning point: by reducing public demand for environmental protection and by increasing a power of capital owners to prevent such protection. Using a large sample (N = 170–174) of countries, we find evidence of the EKC for SO₂ emissions and income inequality has a significant impact on the EKC turning point. Income inequality increases the EKC turning point, suggesting that high inequality can be damaging to the environment. The results are robust to potential outliers, different data sources of income inequality, a different SO₂ emissions measure, changes in model specification, different samples and an alternative estimation method. We also find that inequality appears to be more important than corruption in determining the EKC turning point.

收入不平等对环境有害吗？这个问题的答案在文献中尚未达成共识。本研究旨在通过研究收入不平等对环境库兹涅茨曲线（EKC）的影响，即收入不平等对EKC转折点的影响，来提供有关此问题的见解。不平等可能影响EKC转折点的两个潜在机制：减少公众对环境保护的需求，以及增加资本所有者防止这种保护的权力。使用大量国家（N = 170–174）样本，我们发现了SO ₂的EKC的证据。排放和收入不平等对EKC转折点有重大影响。收入不平等加剧了EKC拐点，表明高度不平等可能损害环境。结果对潜在的异常值，不同的收入不平等数据源，不同的SO ₂排放量度量，模型规格的变化，不同的样本以及替代的估算方法具有鲁棒性。我们还发现，在确定EKC转折点时，不平等似乎比腐败更为重要。