The risk of childhood allergy and atopic diseases is increased 50% by traffic-related pollution, according to a recent study by a German research organization.
“Children living very close to a major road are likely to be exposed not only to a higher amount of traffic-derived particles and gases but also to more freshly emitted aerosols which may be more toxic,” writes Dr. Heinrich. He continued: “Our findings provide strong evidence for the adverse effects of traffic-related air pollutants on atopic diseases as well as on allergic sensitization.”
The study’s author, Joachim Heinrich, Ph.D., of the German Research Center for Environment and Health at the Institute of Epidemiology, in Munich, checked close to 2900 children aged 4, and more than 3000 children aged 6 to establish their rates of asthma and allergy in relation to longterm exposure to traffic-related pollution.
Both groups of children came from the Munich area, and their exposure to traffic pollutants was calculated on the basis opf their homes’ distance from major roads at birth, and at two, three and six years of age. The parents completed questionnaires documenting their child’s respiratory symptoms and diagnoses, and the children were evaluated for asthma, wheezing, sneezing and eczema. The children were checked for food allergies at age six, and air was tested for particulate matter nd nitrogen dioxide at 40 high traffic areas between 1999 and 2000.
Significant positive associations were found between the distance to the nearest road and incidence of asthmatic bronchitis, hay fever, eczema and allergic sensitizations. Also noted was a relationship between proximity to a road and risk of allergic sensitization—subjects living closest to major roads had an almost 50% greater risk of allergic sensitization.
In this study, it was possible to determine that economic factors were not a confounding variable in the analysis, but there was a clear difference in the children’s allergic development with relation to their proximity to a road.
Source: American Journal of Respiratory and Critical Care Medicine, June, 2008 (2nd ed)