Ambient air pollution at home, work and school: Evidence from Ireland.

Most of the existing literature linking air pollution with health outcomes uses data on ambient (i.e., outdoor) air pollution concentrations at or near individuals' residences to proxy personal exposure to air pollution. However, an individual's exposure is influenced by a complex set of factors including the different activities that individuals undertake, by indoor air pollution in the various locations where individuals spend their time, and by the degree of penetration of ambient air pollution into these locations. Apart from their residential address, evidence from time use diaries shows that the location in which adults spend most of their time is their work (for children and young people it is school/college). In this paper, we use micro-data from the 2022 Census of Population for Ireland, matched to air pollution data (PM2.5, PM10, NO2, O3) from the Irish Environmental Protection Agency (EPA), to assess differences in ambient air pollution concentrations at residential and work/school/college locations. The results show that average annual PM2.5, PM10 and particularly NO2 concentrations are greater at individuals' place of work/school/college than at their residential address but the opposite is true for O3. For workers, the contrast between ambient residential and work measurements is more pronounced for more socioeconomically advantaged groups. One of the most important drivers of differences in levels of ambient air pollution at residential and work/school/college locations is spatial commuting patterns (e.g., whether an individual commutes from a rural to an urban location). The findings provide evidence on population subgroups where additional information on activity patterns may enhance exposure estimates.