The impacts of environmental pollution extend beyond the issue of health. Using Chinese survey and administrative data, this study sheds new light on the political costs of environmental pollution. We show that citizens' trust in government officials declines significantly with higher levels of measured pollution, perceptions of increased pollution, and a greater degree of willingness to support environmental protection. Political trust is particularly low when measured as well as perceived pollution are severe. However, the effect of greater willingness to support environmental protection on the erosion of political trust is independent of measured pollution. Our findings suggest that there is a tipping point at which legitimacy acquired primarily through economic achievements could be undermined by environmental degradation, which is a byproduct of economic achievements. It is imperative for the Chinese government to achieve a balance between fast-paced growth and environmental sustainability, to pay attention to the potential political consequences of environmental issues, and to permit more public dialogues and deliberations on the topic of environmental governance.