Women who use a lot of household cleaning products when they are pregnant or shortly after the birth of their baby, may be increasing the risk of their child developing asthma, suggests research from the Children of the 90s study.
The findings, published in this month’s issue of the European Respiratory Journal, indicate high exposure to household chemicals during pregnancy or soon after birth was linked to the child developing wheezing and asthma by the age of seven years.
Asthma is the commonest cause of chronic wheeze in children and, despite large increases in asthma prevalence in many industrialised countries, the causes for the rise in prevalence of asthma have not been fully identified.
Researchers monitored the use of use of household chemicals by pregnant women who were part of the University of Bristol-based study, Children of the 90s – also known as Avon Longitudinal Study of Parents and Children.
They found that children exposed to high levels of chemicals contained in products such as bleach, paint and air freshener had a 41% increased risk of wheezing persistently to the age of 7 ½ years and had slightly lower than normal lung function.
Researchers also carried out skin prick tests on around 7,000 of the children at age 7 which to test for allergies and found that exposure to chemicals had a stronger effect on those children with asthma but without allergies.
Dr John Henderson, lead author of the study and an expert in paediatric respiratory medicine at the University Of Bristol, said small children might be more likely to develop asthma in homes where more chemicals are used.
“We think that is perhaps due to irritant effects of the chemicals on the child after birth, which may cause inflammation of the airways leading to the development of asthma,” he said.
He added, “The importance of this research is that it points to direct effects of chemical exposure on lung development or irritation of the airways after birth.”
Household chemical, persistent wheezing and lung function:effect modification by atopy? J Henderson, A Sherriff, A Farrow and J G Ayres – European Respiratory Journal, March 2008