A lung expert has offered four simple steps to combat the threat of air pollution.

Dr Thom Daniels, a specialist at University Hospitals Southampton, has highlighted these issues after the country marked clean air day on June 20.

It aims to raise awareness of air cleanliness and its crucial impact on health and our environment.

Air pollution, according to Dr Daniels, is “one of the major public health challenges of our time”, and isn't just linked with the climate emergency alone, but also the shortened life, deteriorating health and death of thousands across the UK and globally.

A key contributor is particulate matter (PM), minuscule fragments directly released or created through chemical reactions in our atmosphere.

He said: “Poor air quality is one of the major public health challenges of our time,”

Walking a different route would reduce exposure as air pollution is very localised in time and space, he suggests.

Being outside at a different time to avoid rush hours, between 7am to 9am and 4pm to 6pm, is another precaution, to avoid pollution caused by petrol and diesel vehicles.

Closing windows that face roads, particularly during these hours is beneficial.

With masks already a universal symbol due to the pandemic, their usage while outside can cut down exposure by 50 per cent.

Tight-fitted N95 masks are more effective.

Highlighting the danger of PM, Dr Daniels refers to dust seen in sunlight as a visible example of particulate matter.

However, the more critical particles associated with human health are a tenth of that size.

Dr Daniels also focused on a lesser-known threat: indoor pollution.

He said: "More often than not, the pollution was worse inside than it was outside – and that was not what I was expecting at all.

“There was one occasion where I burnt some toast which filled the kitchen with smoke – the readings were just off the scale."

He said: "This is not just the problem of people with known lung conditions such as asthma or COPD, everyone’s health is at risk from air pollution."

PM's presence has been detected in vital organs and even areas like the testicles, possibly impacting male fertility, but adopting the four-step plan can make a significant difference to our health.