Finnish study links child asthma with structural dampness in buildings

A fresh study by the Environmental Health section of the National Public Health Institute shows a strong link between asthma in children and dampness in the building structures of the home.
According to an article in the upcoming edition of the European Respiratory Journal, at least one in ten, and possibly as many as one in five cases of asthma among children are linked with water damage in the building.

The onset of asthma is the result of the cumulative effect of many factors. Nevertheless, in the 1990s there was a rapid increase in cases of asthma in Finland, as well as an increase in damage caused by dampness in buildings.
More recently, cases of asthma have declined.
The prognosis for young children being treated for asthma is quite good; many are completely cured.
When the small children involved in the study were diagnosed with asthma, two building engineers were sent to the home to look for signs of dampness: leaks of water and stains they may have left behind, discolouration in building materials, flaking paint on walls, fungal odour, or visible fungus.
The engineers also visited the homes of children in a control group. These children, who did not have asthma, were of the same age as the ones who did, living in the same kinds of buildings and in the same area.

It was found that the homes of children with asthma were more likely to have windows that fogged up in cold weather, as well as humidifiers and supplementary heaters.
Dampness and visible fungus in living areas had a significant correlation with the frequency of asthma; fungus in cellars and saunas, where children spend less time than in their bedrooms, were less significant.
The researchers recommended that closer attention be paid to the planning, implementation, and maintenance of buildings.
The degree of the damage also affected the risk of illness. The more serious the damage, the greater the danger that a child might come down with asthma.
The mechanism that leads to the onset of the disease is not known, but materials damaged by dampness and fungus put out particles similar to microbes and spores, as well as even smaller fragments.
It has been estimated that between 84 and 95 per cent of fungus spores and 27 to 46 per cent of fragments can end up in the lungs, and it is believed that the fragments can get into the lower respiratory tracts of small children more easily than that of others, according to laboratory nurse Aino Nevalainen and researcher Anne Hyvärinen in an article in the Finnish medical journal Lääkärilehti. Nevalainen and Hyvärinen conducted the new study along with research professor Juha Pekkarinen.

Dust mites are not seen to be major culprits. Researchers note that there are few dust mites in Finnish homes and that they emerge irregularly, because indoor air tends to be dry most of the year.
Dust mites were as common in the beds of children without asthma as in those of children who have the disease.
Mould in homes ups child asthma risk


Children are significantly more likely to develop asthma by the age of seven if they grow up in homes affected by mould, a new study has found.

Some 470,000 people have asthma in Ireland, including one in every five children. Symptoms can include wheezing, coughing especially at night and frequent chest colds.

The growth of moulds in houses is usually caused by condensation or building defects. If dampness is present for enough time, mould can grow on walls, furniture and clothes. Keeping a house warm and dry and ensuring adequate ventilation are the main ways of avoiding mould.

According to the US researchers who carried out this latest study, ‘early life exposure to mould seems to play a critical role in childhood asthma development’.

They followed the progress of almost 180 children over a seven-year period and found that those who lived in houses affected by mould were three times more likely to develop asthma by the time they reached seven years of age.

“The symptoms of paediatric asthma range from a nagging cough that lingers for days or weeks to sudden episodes of shortness of breath and wheezing that require emergency treatment. If a young child’s symptoms persist and keep coming back, that’s a clue that it could be asthma,” explained the study’s co-author, Dr David Bernstein, of the University of Cincinnati.

The team insisted that this study should ‘motivate expectant parents, especially if they have a family history of allergy or asthma, to correct water damage and reduce the mould burden in their homes to protect the respiratory health of their children’.

by Deborah Condon