Particulate Pollution and the Productivity of Pear Packers
研究发现室外细颗粒物（PM2.5）会渗透进室内，显著降低梨包装工厂工人的生产率，且影响在低于空气质量标准时已出现，而臭氧等不进入室内的污染物则影响甚微。
We study the effect of outdoor air pollution on the productivity of indoor workers at a pear-packing factory. Increases in fine particulate matter (PM 2.5 ), a pollutant that readily penetrates indoors, leads to significant decreases in productivity, with effects arising at levels below air quality standards. In contrast, pollutants that do not travel indoors, such as ozone, have little, if any, effect on productivity. This effect of outdoor pollution on indoor worker productivity suggests an overlooked consequence of pollution. Back-of-the-envelope calculations suggest the labor savings from nationwide reductions in PM 2.5 generated a sizable fraction of total welfare benefits.