Traffic pollution ups asthma risk

Children born in areas with high levels of traffic-related pollution may be at an increased risk of developing asthma due to genetic changes acquired in the womb, the results of a new study indicate.

US researchers studied the relationship between PAH exposure and childhood asthma. PAHs (polycyclic aromatic hydrocarbons) are chemical compounds that are created as byproducts of incomplete combustion from carbon-containing fuels. They are found in high levels in areas affected by heavy traffic and exposure to them has been liked to diseases such as cancer and childhood asthma.

The researchers suggested that exposure to PAHs while still in the womb (via the placenta) could ‘reprogram’ foetal genes and lead to airway inflammation or asthma during childhood.

They studied the umbilical cord blood of children living in New York city and discovered evidence of an alteration in a specific gene – ACSL3 – that is associated with prenatal exposure to PAHs.

"Our data supports the concept that environmental exposures can interact with genes during key developmental periods to trigger disease onset later in life, and that tissues are being reprogrammed to become abnormal later," said researcher, Dr Shuk-mei Ho, of the University of Cincinnati.

The team believes these findings provide a potential clue for predicting environmentally related asthma in children, particularly those born to mothers who live in high-traffic areas when pregnant.

With confirmation in further studies, the researchers believe that changes in the ACSL3 gene could serve as a novel biomarker for early diagnosis of pollution-related asthma.

"This research is aimed at detecting early signs of asthma risk so that we can better prevent this chronic disease that affects as many as 25 percent of children…Understanding early predictors of asthma is an important area of investigation because they represent potential clinical targets for intervention,” the team added.

Details of these findings are published in the journal, PloS One.

According to the Asthma Society of Ireland, one in five children in Ireland have asthma. For more information on the condition, see our clinic at…http://www.irishhealth.com/clin/asthma/index.html

[Posted: Mon 16/02/2009]