Image caption The backpack used during the experiment

Scientists in Edinburgh are using hi-tech backpacks to study personal exposure to air pollution.

Air pollution is routinely measured by a network of urban monitors at fixed locations across Scotland.

But these are unable to provide a detailed picture of an individual's exposure throughout the day.

Scientists at the Centre for Ecology & Hydrology have provided volunteers with backpacks fitted with particle monitors and GPS satellite tracking technology.

Media playback is unsupported on your device Media caption Graph on laptop, showing David’s exposure to air pollution in Edinburgh

The volunteers wear the small backpacks throughout the day and sleep with them beside their beds at night.

The results are then analysed to assess exposure to tiny particles, mainly from combustion, known as particulate matter.

Doctors say there is a strong link between exposure to particulate matter and the risk of heart attack.

Analysis I am a regular cyclist, I walk a fair bit and my job means I often have to drive long distances. I also travel between Edinburgh and Glasgow by train and rely on the capital's excellent bus service. That made me an ideal guinea pig for the research project being conducted by the Centre for Ecology & Hydrology. Cycling up Edinburgh's steep hills frequently leaves me breathing heavily, increasing my exposure to air pollution. It is something I have long been concerned about. In fact, I have already changed the route I use to cycle to work. These days, I use a longer route along quieter, less congested streets. So I was more than a little curious, perhaps even anxious, to discover my test results. The news that my exposure to air pollution while sitting in a car in city centre traffic could also be a threat to my health had done little to reassure me. Dr Stefan Reis was able to tell me my greatest exposure to particulate matter, linked to heart attacks, came while walking along Princes Street in Edinburgh during rush hour. The large red spike on Dr Reis' computer screen told its own story. The high number of buses, idling at bus stops and stuck in traffic, was to blame. The results provide a simple snapshot of one man's exposure to air pollution. But, for me, it was a personal reminder of the connection between high levels of pollution and ill health.

Professor Dave Newby, of the University of Edinburgh and the British Heart Foundation, said: "We all think that when we breathe in air pollution, it must provoke pneumonia, or asthma or lung problems. But actually, it kills far more people from heart disease.

"What we've found is that the biggest trigger is the particulate matter that we breathe in. In the urban environment, the biggest contributor to that is diesel engines."

The research investigating personal exposure to air pollution is being led by Dr Stefan Reis.

He believes the development of mobile air pollution monitoring equipment will be cheaper and more effective than investing in a larger network of fixed monitoring stations to cover whole cities.

He told BBC Scotland: "It's always easy to call for more monitoring but what we are trying to achieve is getting smarter monitoring.

"We're not trying to cover the whole countryside or city with many, very accurate monitors, which are very expensive, but using the combination of personal sensors, monitors on buses or trams, together with existing networks to get a much better picture of the actual exposure of people in the city."

The Scottish government has rejected criticism from environmentalists, who say ministers are failing in their duty to reduce air pollution levels.

Environment minister Paul Wheelhouse said: "Working in partnership with local authorities, we've developed a network of monitoring sites, there's over 90 of them in Scotland, and we're using those to develop our strategy at a local level.

"In some cases, where they fail to meet the Scottish standard, which is a tough standard, they identify an air quality management area and that then triggers between the Scottish government and the local authority, who have a duty to deliver good air quality locally, to tackle that."

Image caption Roadside air pollution monitoring station

But Green MSP Patrick Harvie argues air pollution levels will remain too high until there is a fundamental change in transport policy in Scotland.

He said: "This locked-in pattern that we have to high transport demand is expensive, it's inefficient, it's unhealthy and it contributes to local and global pollution.

"Unless we see change in transport policy, we are not going to see change to the pollution levels in our cities and we'll be here in another 10 years listening to another environment minister saying much the same thing."