Report demands action to stop traffic fumes contributing to dementia

The Committee on the Medical Effects of Air Pollution (COMEAP) believes it is ‘likely’ that toxic emissions are increasing the risk of developing one of the most devastating degenerative cognitive conditions. 

A new report has called for action to be taken to stop traffic fumes and other air pollutants contributing to the prevalence of dementia in the UK. Published by COMEAP, the study has concluded there is now sufficient evidence to suggest an association between ambient air pollutant and accelerated decline in cognitive function associated with ageing, and the risk of developing dementia. 

Various plausible biological mechanisms have been proposed that could explain this connection, some of which have been demonstrated in experimental studies. These include the effect of air pollution on the cardiovascular system having a secondary effect on the brain. Meanwhile, small particles breathed in the form of PM2.5 could translocate within the body, moving from lung to blood stream and then brain, although there is no clear understanding of whether this occurs in enough volume to damage the brain.

‘There is evidence that air pollution, particularly particulate air pollution, increases the risk of cardiovascular, including cerebrovascular, disease. These diseases are known to have
adverse effects on cognitive function. It is therefore our view that there is likely to be a
causal association between particulate air pollution and effects on cognitive function in older people,’ the report said. 

In its summary, the report acknowledges that more evidence is needed to determine if air pollution can have effect brain function and health at concentration levels currently recorded in the UK. At the time of publication, no specific recommendations have been made on how to quantify the effects of air pollution on dementia. 

‘It may be possible to develop an indirect method of quantification of cognitive effects secondary to the effects of particulate pollution on cardiovascular disease. This would require a review of evidence regarding the quantitative link between cardiovascular endpoints and effects on cognition,’ the report continued. 

‘Today’s report from the UK Government is further evidence that air pollution is devastating for human health, and it’s really worrying to see the links with dementia being strengthened. We have known for a long time that traffic fumes cause asthma and heart conditions, and evidence has been growing about the risk that tiny particles – from exhaust fumes, tyres and brakes – pose to our cognitive health. It is particularly dangerous for young children, the elderly, and people with pre-existing health conditions,’ said Friends of the Earth Scotland’s transport campaigner, Gavin Thompson. 

Previous studies have identified a potential link between air pollution and dementia in women, and ambient pollution and slower brain development in children. 

Image credit: Danie Franco