Change of Modeled Exposure to Traffic-related Pollutants During the First 6 Years of Life in the Munich Birth Cohorts (GINI and LISA)

Abstract

SS6-09 Abstract: There is a strong need for individually based exposure assessment to air pollutants. In particular for long-term exposure studies on health effects of traffic-related air pollutants (TAP), data from geographic information systems (GIS) are useful. GIS data could be used to calculate distances to major roads and to model exposure to traffic-related air pollutants by complex modeling techniques. In the framework of the EU-funded TRAPCA project, such regression models were developed and successfully applied to the residential addresses of the members of our birth cohorts. Because families are moving, in particular when families are growing, the effects of moving on lifelong exposure estimates to TAP or changed exposure levels over time might improve total exposure assessment of the cohort members. Within an ongoing birth cohort study in the metropolitan area of Munich, we aim to analyze the change of the GIS-based modeled exposure to TAP during the first 6 years of life. The children of the 2 ongoing birth cohorts GINI and LISA in the metropolitan area of Munich, which were recruited between the years 1995 and 1998, will be used to study effects of long-term exposure health effects to TAP. A total of 3586 newborns were recruited in this area and 86% could be followed up until the age of 6 years. During the follow-up period of 6 years, 1390 children had moved at least once (39%) within the Munich metropolitan area, and of 710 children, residential addresses were available at the age of 6 years. Residential addresses of the newborns were geocoded and GIS data on street type (as a proxy for traffic volume), land coverage, population, and household density were available to calculate distances between residential addresses and major roads as well as estimates of concentrations of TAP at the residential addresses on the bases of the complex model. Within the group of movers between birth and 6 years, the distance to major road at birth and at 6 years was moderately correlated (r = 0.38). Also, the modeled exposure to PM2.5 and black smoke was moderately correlated with r = 0.42 and r = 0.73. For NO2, the correlation was very low (r = 0.10). However, there was as well a tendency to wider distances to major roads and to lower exposures to TAP, especially for NO2, at the age of 6 years compared with the results from the residential addresses at birth. These data indicate that young families lower their exposure to TAP by moving into the suburbs of the metropolitan area.