Researchers looked at clinic and survey data from 13,988 participants in the Children of the 90s study at the University of Bristol. They analysed lung function measurements, an under-researched area in relation to mould, at ages 8, 15, and 24 and parent-reported measures of household indoor mould at 5 years old. Data on whether an asthma diagnosis was given by a doctor was also used.
At 8 years old, two different measures of lung capacity (FEV1, the volume of air forcefully exhaled in one second and FVC, the volume of air forcefully exhaled after a deep breath) were both reduced by 2.4%. At 15 years old, FEV1 had reduced by 5.7% and FVC by 6%. For comparison, other studies have found passive smoking in the first two years of life may cause declines in children’s FEV1 of only 0.5%.
The study shows strong evidence that exposure to indoor mould in childhood is linked with reduced lung function in childhood and adolescence, but does not necessarily impact in early adulthood.
Dr Joshua Khan, lead author of the study, said:
“We know that lung function in early adulthood is linked to long-term health, including the risk of illness and early death later in life. That’s why it’s so important to understand the impact of factors like indoor mould – and this study shows it really matters for children’s lung health.
“Indoor mould is common and expected to increase due to climate change, as heavy rain and increased stormy weather become more frequent, making this an even more important public health topic to research.”
This study supports the need for further research to understand when children are most vulnerable and what the impact of interventions to reduce mould exposure have on respiratory health.
One limitation of the study is that parents’ reporting of indoor mould exposure is subjective, so it may be under or overreported based on their perception.