Pollution raises infection risk, research suggests

Exposure to air pollution could make people more vulnerable to infection, scientists at a Scottish university have claimed.

A team led by immunology expert Dr Peter Barlow has produced research that suggests particles found in traffic fumes can damage the immune system’s ability to kill viruses and bacteria.

Particles found in traffic fumes can damage the immune system’s ability to kill viruses, a study has suggested

The work carried out by scientists at Edinburgh Napier University is the first to show this effect and its ‘significant human health implications’, the researchers claim.

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

Researchers at the School of Applied Sciences suggested peptides have virus-killing properties which could prove crucial in developing a cure for the common cold.

However, the paper published last week in The Journal of Immunology, suggests that particles found in air pollution can prevent peptides working properly.

Infection

Study Director Dr Barlow and researcher Dr Fern Findlay, working in collaboration with the US Centres for Disease Control and Prevention, and the Midlothian-based Moredun Research Institute, found carbon particles could trigger changes in the antimicrobial peptides, potentially resulting in “an increased susceptibility to infection”.

According to the researchers, the implications are profound for people living in areas of high air pollution, who breathe in high concentrations of particles every day or absorb them through skin contact, especially those with pre-existing lung conditions like asthma or COPD.

Dr Barlow, Associate Professor of Immunology & Infection at Edinburgh Napier, said: “This is an area of research that is very poorly understood.

Dr Peter Barlow, senior lecturer, School of Applied Sciences

“We were extremely concerned when we found that 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 that strong action plans are put in place to rapidly reduce particulate air pollution in our towns and cities.”

‘More study needed’

Commenting on the study, Dr Sheena Cruickshank of the British Society for Immunology, and Senior Lecturer in Immunology at the University of Manchester, said: “This interesting study shows that incubation of carbon nanomaterials can inhibit the function of one of our anti-bacterial peptides. However it is not clear how the carbon nanomaterials reflect our physiological exposure to the complex cocktail of pollutants (which include particulate matter (PM2.5 and PM10) such as sulphur dioxide, nitrogen oxide particles and carbon monoxide) as the work was purely done in cell model systems.

“Furthermore, the immune system has multiple layers of defence, including other anti-bacterial products and a variety of effector cells, and only one anti-bacterial product is assessed in this paper; therefore much more work needs to be done to assess the significance of this finding. However, this is an interesting, albeit relatively preliminary, study that suggests this is an important research area which should be investigated further.”