We investigate the heterogeneous effects of particle pollution on Italian daily hospitalizations and their costs by exploiting public transportation strikes as plausibly-exogenous shocks in pollution exposure. We find that a one standard deviation increase in PM${}_{10}$ causes additional 0.79 hospitalizations per 100,000 residents, and the effect is stronger for the elderly, low educated individuals and migrants. Furthermore, we find that young individuals, an arguably healthy age group, exhibit economically meaningful responses to air pollution with an effect ranging between 0.45 and 1.04. Our results imply a large role of avoidance behavior driving heterogeneous marginal health effects. Total daily costs of a one standard deviation increase in ${\text{PM}}_{10}$ represent 0.5% of the total daily health expenditure, and 85% of this additional spending comes from more patients hospitalized, while the remaining 15% can be attributable to more costly, and likely more complex, hospitalizations.

我们通过利用公共交通罢工作为污染暴露的合理外源冲击来研究颗粒污染对意大利日常住院治疗及其成本的异质性影响。我们发现 PM 增加了一个标准差${}_{10}$每 10 万居民增加 0.79 人住院，对老年人、受教育程度低的人和流动人口的影响更大。此外，我们发现年轻人，一个可以说是健康的年龄组，对空气污染表现出经济上有意义的反应，影响在 0.45 到 1.04 之间。我们的结果暗示回避行为在驱动异质边际健康影响方面发挥了重要作用。每增加一个标准差的每日总成本${\text{下午}}_{10}$占每日卫生总支出的 0.5%，其中 85% 的额外支出来自更多住院患者，而剩余的 15% 可归因于更昂贵且可能更复杂的住院治疗。