AIR pollution levels in parts of Newport are among the worst in the UK and greatly exceed international targets.

Residents in several parts of the city are breathing in dangerous levels of pollutants, which scientists have linked to a higher risk of strokes, heart disease and lung problems.

Newport has for several years tracked pollution levels in a series of Air Quality Management Areas (AQMAs), including a handful that run along the M4.

The city's 11 AQMAs monitor levels of nitrogen dioxide (NO2), a gas that is emitted during the burning of fossil fuels, such as in car engines.

Even short-term exposure to this type of pollution can cause inflamed airways and exacerbate pre-existing heart and lung conditions.

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Using new research by addresspollution.org - which allows people to search for air quality information in their postcode area - the Argus searched pollution levels in Newport's 11 AQMAs to find out how bad the situation is there.

Four areas alongside the M4 recorded some of the highest pollution levels in the UK.

People living near the western end of the Brynglas Tunnels are at risk of nitrogen dioxide levels nearly five times higher than the limits set by the World Health Organisation (WHO).

Similarly, the NO2 levels at motorway Junction 27, in High Cross, are more than four times higher than the WHO recommends. The same is true of levels along a stretch of Cefn Road in Rogerstone.

South Wales Argus:

Indeed, the levels of NO2 in all 11 of the city's Air Quality Management Areas were more than twice the WHO limit.

While five of these areas cover parts of the motorway, others are more diverse - from Clarence Place to the centre of Caerleon.

The addresspollution.org research also lets people see local levels of two other pollutants called particulate matter (PM), referring to anything airborne which is not a gas, including potentially harmful chemicals.

PM can be harmful because the small size of many of particles means toxins can enter the bloodstream and be transported around the body, getting stuck in vital organs like the heart and lungs.

The research tool shows many parts of Newport also exceed World Health Organisation-set limits on PM levels.

South Wales Argus: Map showing the location of Newport's 11 Air Quality Management Areas. Map source: GoogleMap showing the location of Newport's 11 Air Quality Management Areas. Map source: Google

All of the city's 11 AQMAs recorded between 20 per cent and around 60 per cent higher levels of PM10 (particles smaller than 10 micrometres in diameter) than those set by the WHO.

For smaller PM2.5 particles, which are potentially more dangerous, Newport's 11 Air Quality Management Areas all record levels between two and three times higher than what the WHO deems to be a safe limit.

Humphrey Milles is the founder of COPI (the Central Office of Public Interest), which made the addresspollution.org website. He said: "Air pollution affects all of us. It’s a group one cause of cancer, just like asbestos.

"With this new accurate data now publicly available, it would be shameful for the property industry to not start acting transparently. Lives depend on it.

"Everyone has a right to know what they’re breathing before they buy or rent. And of course, we have our own part to play in this too. Air pollution isn’t insurmountable and we can all do something about it."

Air pollution targets for NO2, PM10 and PM2.5 set by the WHO are lower than those set by the UK Government.