Parents striving to keep a spotless house may unwittingly be triggering asthma in their children, a study says.
Indoor 'cleaning' fumes increased asthma risk
Toddlers exposed to fumes from solvents and cleaning products at home are most at risk, Australian researchers found.
Polishes, room fresheners and new carpets were some of the triggers identified by a Curtin University of Technology team, Thorax reported.
Children exposed to the highest levels of volatile organic compounds were four times more likely to have asthma.
The authors measured levels of volatile organic compounds (VOCs) in the homes of 88 toddlers with asthma and 104 without.
Levels measured were lower than recommended maximums.
VOCs are irritants and indoor sources include solvents, floor adhesives, paint, furnishings and cleaning products.
Levels were measured twice - once in the winter and again in the summer.
The children's parents were asked to fill out a detailed questionnaire on their child's health.
The researchers also tested the children for allergies.
When the researchers looked at the individual types of VOCs, most appeared to be risk factors for asthma.
In particular, benzene - which is used to make rubbers, dyes and detergents and is also a component of gasoline, which has been linked to cancers - almost tripled the risk of asthma for every 10 unit increase of this compound.
Another important risk factor for asthma was allergy.
Three-quarters of the children with asthma had an allergy, compared with only half of the children without asthma.
Lead researcher Dr Krassi Rumchev said given that some VOCs have also been shown to cause cancer, it would be important to determine acceptable indoor levels and what factors increase levels.
"Domestic exposure to VOCs at levels below currently accepted recommendations may increase the risk of childhood asthma," they said.
Measuring total VOCs might underestimate the risks associated with individual compounds, they added.
Dr Matthew Hallsworth, from Asthma UK, said: "There has already been a lot of debate about whether outdoor air pollution may increase the risk of developing asthma.
"This study reminds us that we should also consider indoor air quality and how it may affect the health of our lungs."