Swedish study links exposure to air pollution in first year of life with risk of asthma and allergies
April 9 2008
Story by Kathryn Senior from information in an original press release from the AlphaGalileo news service
Swedish researchers working within the BAMSE project have studied children in Stockholm for 12 years. They report today children exposed to a lot of air pollution when they were very young - between birth and their first birthday - are much more likely to develop the symptoms of asthma later in life. The children, who are all now 12 years old, also suffer more allergies to pollen (hay fever) and problems with breathing generally.
Does pollution cause asthma?
After monitoring pollution when children were young and their risk of developing asthma, the researchers conclude that the environmental factors of exposure to air pollution are playing a significant role in asthma risk. However, they have also detected that the genes of the children are also important.
A total of 4000 children were included in the study. Measurements of the level of air pollution caused by traffic exhaust fumes was measured at their homes. All were monitored by regular health checks, which looked for signs of asthma, pollen allergies and other respiratory problems.
Analysis of their data revealed that kids who experienced high levels of pollution during the first year of their life were 60 per cent more likely to develop asthma by the age of 12. Pollution and asthma seem to be linked.
But what about the genetic factors involved?
One of the genes in our body cells that helps us deal with air pollutants is called GSTP1 - this codes for an enzyme called glutathione S-transferase (GSTP). This enzyme produces chemicals called antioxidants that mop up the damaging free radicals that are formed in the body when it encounters the chemicals in air pollution.
Children with some forms of GSTP1 were more likely to develop asthma, no matter how great their exposure to pollution. Children at high risk because of their GSTP1 gene were even more badly affected if they had a variant of the tumour necrosis factor (TNF) gene, also known to predispose to asthma. Children with a particular combination of GSTP1 and TNF variants are at very high risk of developing allergies.
The study organisers have put together an on-line follow-up survey of the children and their parents that will provide information about health, lifestyle and environmental conditions, including air pollution, during the children’s lives.
Links
The BAMSE project is run by the Stockholm County Council’s unit for Occupational and Environmental Medicine and the Institute of Environmental Medicine at Karolinska Institutet.
For more information about pollution, asthma and how they might be linked, try this site.
This page also has some details about traffic pollution asthma associations. | 
