Mitigating greenhouse gas emissions and reducing air pollution represent two pressing and interwoven environmental challenges. While international carbon markets, such as the European Union emissions trading system (EU ETS), have demonstrated their effectiveness in curbing carbon emissions (CO 2 ), their indirect impact on hazardous co-pollutants remains understudied. This study investigates how key toxic air pollutants—sulfur dioxide (SO 2 ), fine particulate matter (PM 2.5 ), and nitrogen oxides (NO x )—evolved after the introduction of the EU ETS with a comparative analysis of regulated and unregulated sectors. Leveraging the generalized synthetic control method, we offer an ex post analysis of how the EU ETS and concurrent emission standards may have jointly generated sizable pollution reductions in regulated sectors between 2005 and 2021. We provide an aggregate assessment that these pollution reductions could translate into large health co-benefits, potentially in the hundreds of billions of Euros, even when bounding the effect of emission standards. These order-of-magnitude estimates underscore key implications for policy appraisal and motivate further microlevel research around the health co-benefits of carbon abatement.

中文翻译：

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欧盟排放交易体系可能会从减少污染中产生巨大的协同效益


减少温室气体排放和减少空气污染是两个紧迫且相互交织的环境挑战。尽管国际碳市场，例如欧盟排放交易体系（EU ETS），已经证明了其在抑制碳排放（CO 2 ）方面的有效性，但其对有害共污染物的间接影响仍然没有得到充分研究。本研究通过对受监管和不受监管部门的比较分析，调查了引入 EU ETS 后主要有毒空气污染物——二氧化硫 (SO 2 )、细颗粒物 (PM 2.5 ) 和氮氧化物 (NO x ) 的演变情况。利用广义综合控制方法，我们对欧盟排放交易体系和同步排放标准如何在 2005 年至 2021 年间共同实现受监管部门的污染大幅减少进行了事后分析。我们提供了一项总体评估，表明这些污染减少可能会转化为巨大的污染排放。即使在限制排放标准的影响的情况下，健康的共同效益也可能达到数千亿欧元。这些数量级的估计强调了政策评估的关键影响，并激励围绕碳减排的健康协同效益进行进一步的微观研究。