Ambient air pollution-related environmental inequality and environmental dissimilarity in Helsinki Metropolitan Area, Finland

Most studies suggest that people with lower socio-economic status (SES) are exposed to higher air pollution levels. Research from Europe, on the other hand, have shown mixed results, often indicating non-linear patterns, necessitating a better understanding of the context-specific manifestation of the relationship between SES and air pollution. The results of our generalized additive model show that median income of inhabitants has an inverted U-shaped relationship with air pollution in Helsinki Metropolitan Area, Finland. However, when the spatial distribution of people belonging to certain income groups is considered in applying an environmental dissimilarity analysis, low-income people are found to be more adversely dispersed compared to other income groups. By contrasting additional built environment and socio-economic characteristics of the total population and of the low-income people's hotspots for environmental dissimilarity, we present further indications of environmental injustice regarding car ownership, heating types and ownership structure of the building stock.