The measures were made per 10,000 of the population.
Targets to reduce sulphur dioxide (SO2), fine particulate matter (PM2.5), ammonia and nitrogen oxides are all set to be missed, according to data from Defra.
Though there are several ways to measure air pollution, PM2.5 – tiny particles formed as a result of burning fuel and chemical reactions that take place in the atmosphere – are a commonly-used measure.
Because these particles are so small, they are considered dangerous to humans because they can bypass the nose and throat, lodging in lungs and causing long-term problems.
Sign up to our daily Wakefield Express Today newsletter
The i newsletter cut through the noise
The Welsh city of Swansea came out at the top of the PM2.5 scale per 10,000 of the population.
According to the latest data (collected in 2019) from Centre for Cities, these are the 10 areas in the UK with the highest concentrations of PM2.5 particles per 10,000 of the population.
The city with the next highest PM2.5 pollution levels was Belfast, according to National Atmospheric Emissions Inventory data.
Newport, where a Sustainable Travel Strategy was adopted by the council in 2019, had the third-highest levels of PM2.5 particles per head in the same year.
Close behind was Warrington, which also had high levels of PM2.5 particles per head.
Norwich is one of 32 UK cities where air pollution levels exceed World Health Organisation limits, and had the fifth highest level of fine particle pollution in 2019.
Burnley came out with the sixth-highest concentration of PM2.5 particles in the UK.
Much further down south, Portsmouth also suffers from poor air quality, with air quality worse than London in certain areas.
Air pollution-related deaths in Swindon are reportedly much higher than in other parts of the South West. In 2019, it ranked as the place with the eighth-highest level of PM2.5 pollution particles.
Aldershot, in Hampshire, had the ninth highest concentration per head.
Over in Kent, Chatham also had high levels of PM2.5 pollution particles, ranking tenth in the UK per head.