How pollution can get into your brain

TINY particles of pollution in the air could raise the risk of dementia by 92 per cent, according to a study by the University of Southern California.

Researchers analysed data from more than 3,600 women aged between 65 and 79 and found that those who lived in heavily polluted areas were 81 per cent more at risk of cognitive decline.

This could be because toxic fumes infiltrate brain cells. ‘What’s disturbing is that pollution is making its way to the brain,’ says Alastair Lewis, a professor of atmospheric chemistry at the University of York. ‘The brain should be protected because of the blood brain barrier — a membrane that stops the influx of damaging compounds. But these studies show the brain’s barrier is not perfect.

‘You also have to consider that polluted air goes directly up the nose, where the olfactory nerves — which relay sensory information such as smell — are a very efficient route to the brain. So links between dementia and pollution seem credible.’

Last month, researchers revealed that pollution can also affect mental abilities by shrinking white matter, a substance that covers most of the brain. Older men appear to be worst affected.