Self-reported traffic exposure is not strongly correlated with modelled NOx in a Northern European cohort study

Abstract

Background Few studies have investigated the association between self-reported and modelled exposure to traffic pollutants. Aim To examine the correlation between modelled NOx and self-reported exposure in 7 northern European cities. Material and methods In 2011 RHINE (Respiratory Health in Northern Europe, rhine.nu) self-reported exposure was measured with two questions; “Is your bedroom window near a street (less than 20m)” with replies from “No” to “Yes, with very much traffic” and “Do you hear traffic noise from your bedroom?” with replies from “No” to “A lot”. Vehicle exhaust (NOx) was modelled for urban areas and NOx quartile correlated with self-reported exposure. Results Participation rates varied. The presence and size of a street near the bedroom window correlated significantly with modelled NOx. Traffic noise correlated with modelled NOx in most centres, all correlations were moderate. Conclusion Self-reported traffic exposure have low or moderate correlations with modelled vehicle exhaust concentration level.