Résumé
The adverse health impacts of air pollution have been subject of much research and providethe usual rationale for policy interventions in this area. It is only recently being recognizedthat polluted air might also imply direct economic costs by reducing labor productivity. Recentstudies show that that short-term exposure to ozone (O3) and particulate matter (PM2:5)signi cantly reduces the daily productivity of unskilled workers engaged in physical work (fruitpicking and packing). However, most work - and in particular most high value work - in amodern economy is based on mental-dexterity, often with little or no physical dimension (e.g.lawyers, administrators, teachers, nanciers, computer programmers). Thus, there is a stronginterest in studying the impact of pollution on cognitive performances. We take advantage ofthe design of the US HRS survey (respondents are interviewed every two years over 12 years)to study this relationship. We nd that exposure to PM2:5 at the WHO recommended dailypollution limit reduces performances by 2.5%. When we focus on respondents living in lowvalue houses on highly polluted day this e ect even climbs to 12%, suggesting that air pollutionmight even strenghen economic inequality.