A new study conducted in the UK has shown that exposure to different air pollutants affects brain and lung function in different ways, even with the same number of particles. The scientists found that it is the composition of the pollutant that plays a key role in assessing its impact on health, rather than the concentration of suspended particles. The findings could influence future indoor air quality standards.
The study was led by Thomas Flaherty of the University of Birmingham. It examined exposure to:
🌲 wood smoke
🚛 diesel engine exhaust
🍳 cooking fumes
🧴 limonene aerosols produced when using certain cleaning products
Fifteen healthy volunteers over 50 with a family history of dementia breathed each pollutant for an hour in a sealed chamber through a mask, with a two-week interval between exposures.
After exposure to wood smoke and limonene aerosols, participants showed a subtle but measurable decrease in lung function, although readings remained within the normal range.
In cognitive tests:
reaction time improved after inhaling diesel exhaust and wood smoke (which the authors attribute to the presence of nitric oxide, which dilates blood vessels and increases blood flow to the brain);
in tasks requiring sustained attention, the best results were recorded after clean air, and the worst after diesel fumes.
Limonene contributed to improved memory in simple tasks, while cooking fumes did not produce this effect. Each pollution source formed its own pattern of short-term changes in lung and brain function.