AIR pollution can jeopardise the immune system and make people more vulnerable to infection, research has revealed.

A team led by Edinburgh-based immunology expert Dr Peter Barlow has demonstrated for the first time that nano-sized particles found in traffic fumes can damage the immune system’s ability to kill viruses and bacteria.

While the potential link between car-choked streets and illness has been the subject of much debate, the work at

Edinburgh Napier University is the first to show this effect.

The development is expected to prompt calls for the UK Government to step up efforts to tackle air pollution following its recently announced plans to ban the sale of new diesel and petrol cars by 2040.

The university study focused on antimicrobial peptides, tiny molecules found in the immune systems of humans and animals which increase in response to infection.

Researchers at Napier’s School of Applied Sciences recently revealed these peptides have virus-killing properties that could prove crucial in developing a cure for the common cold. However, the new paper, published in the Journal Of Immunology, reveals particles found in air pollution can prevent peptides working properly.

The study has major public health implications for people living in areas of high air pollution, who breathe in huge concentrations of particles every day or absorb them through skin contact, especially those with pre-existing lung conditions such as asthma or chronic obstructive pulmonary disease.

Dr Barlow, associate professor of Immunology & Infection at Edinburgh Napier, said: “We were extremely concerned when we found air pollution particles could inhibit the activity of these molecules, which are absolutely essential in the fight against infection. In light of these findings, we urge strong plans are put in place to rapidly reduce particulate air pollution in our towns and cities.”

Emilia Hanna, air pollution campaigner at Friends Of The Earth Scotland, said the findings reinforced the case for low emission zones in all major cities and for 10 per cent of central and local government transport budgets to be spent on walking and cycle infrastructure to reduce pollution.

She added: “This study adds to the

mountain of evidence that air pollution damages our health. Levels of toxic pollution are breaking both European and

Scottish regulations on air quality in all our major cities, posing a threat to our health and in particular the health of those whose bodies are still developing.

“Air pollution impacts disproportionately on those who are least responsible for

causing the problem, including children, the elderly, and people living in poverty.”