Using cleaning sprays and air fresheners while doing housework may account for up to one in seven cases of asthma in adults, a study has found.

Just spraying a cleaner once a week can trigger an attack, according to the research. The more often the sprays are used, the higher the risk.

"Frequent use of household cleaning sprays may be an important risk factor for adult asthma," said Jan-Paul Zock, of the Municipal Institute of Medical Research in Barcelona, Spain. "The relative risk rates of developing adult asthma in relation to exposure to cleaning products could account for as much as 15 percent, or one in seven, of adult asthma cases."

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Furniture sprays, glass-cleaners and air freshener sprays were associated with the highest risk of a person developing asthma after doing the housework. No link was identified between the onset of asthma and the use of cleaning products that were not sprayed.

Cleaning sprays have previously been found to be associated with an increased incidence of asthma among people who clean for a living but this is thought to be the first time the link has been made to routine household use.

The results of the study were published by the American Thoracic Society in the American Journal of Respiratory and Critical Care Medicine.

The international study involved 3,503 people ages 20 to 44 in 10 European countries who used cleaning and air freshener sprays. Their details first were logged, on average, nine years before they were interviewed by the study team.

Of the subjects, 6 percent had developed asthma symptoms and the study claims there is a link between the disease and use of sprays in the home at least once a week.

Analysis revealed that using the sprays at this rate, as 42 percent of the study group did, increased the risk of asthma symptoms by 30 to 50 percent.