Social Inequalities in Exposure to Air Pollution in the EPIC Cohorts of Turin and Varese.

In Europe, evidence on the relationship between socioeconomic position (SEP) and air pollution exposure is mixed. We assessed the association between individual SEP (education and occupation) and air pollution in the Turin and Varese European Prospective Investigation into Cancer and Nutrition cohorts. This cross-sectional study included participants enrolled between 1992-1998, categorised by three educational (high, medium, and low) and three occupational (high-, medium-, and low-skilled) levels. Air pollution exposure (2008-2011) at residential addresses was estimated using Land Use Regression models. Nitrogen dioxide (NO₂) and nitrogen oxide (NOx) data were available for both cohorts; particulate matter (PM_2.5, PM₁₀) only for Turin. Linear regression models (adjusted for sex, age, and marital status) estimated associations between SEP and annual mean pollutant concentrations (µg/m³), stratified by cohort. In Varese, lower education was associated with lower NOx exposure. In Turin, medium and low education were also linked to lower NOx exposure, though without a clear gradient. In both cohorts, individuals in medium- and low-skilled occupations had lower nitrogen exposure than those in high-skilled jobs. Associations between SEP and PM exposure in Turin were weak to null. In conclusion, lower SEP was associated with slightly lower nitrogen exposure; no clear link was found with PM.