Air pollution causes one in 20 deaths in the Forest of Dean, new figures show.
Campaigners have criticised the Government's slow response to "dangerous fine particle air pollution", and urged it to bring the UK's air quality targets in line with global health advice.
June 20th is National Clean Air Day, which is an opportunity for people to write to their local councillors and MPs to express concerns regarding their local area's air quality.
Office for Health Improvement and Disparities figures show air pollution was responsible for 4.8% of the deaths of people in the Forest of Dean aged over 30 in 2022.
This was down from 5% the year before, and was below pre-pandemic levels of 6.1%.
Imogen Martineau, head of UK portfolio at the Clean Air Fund, said the UK is "going in the wrong direction in tackling air pollution".
The Government says it wants to halve pollution levels of fine particles to reach an annual mean concentration of 10 micrograms per cubic metre by 2040.
The World Health Organization's current advice says this figure should be no more than five micrograms per cubic metre.
Ms Martineau said policymakers must work towards the WHO's air quality guidelines, adding: "It’s time to recognise the co-benefits which clean air can bring – better health, action on climate change, and improved economies."
The figures showed significant regional inequality across England, with 17 of the 18 areas with the worst air pollution death rates in London. The other was Watford, a commuter town in the East of England.
In London in 2022, 7.1% of the deaths of people aged 30 or above were due to air pollution.
At the other end of the scale, the 11 areas with the lowest proportion of air pollution-related deaths were all in the South West, with air pollution responsible for 4.6% of deaths in the region.
Larissa Lockwood, director of clean air at Global Action Plan, said: "The solutions to our air pollution problem already exist. We need the Government to take urgent action to ensure everyone in the UK can breathe cleaner air."
Ms Lockwood said providing people with greener travel options and phasing out wood burning in urban areas would help improve air quality.
"No one should have their life cut short because they do not have access to clean air," she added.
Friends of the Earth said the Government "is not acknowledging" the dangers of air pollution.
Climate, transport and air pollution campaigner Jenny Bates said: "The Government must act now by bringing particulate matter targets in line with the WHO’s interim guidelines by 2030, and enshrine the right to clean air."
A government spokesperson said it has made "significant progress improving air quality since 2010".
They said: "We have delivered significant reductions in emissions – with fine particulate matter falling by 24%, and nitrogen oxides down by 48%.
"We also met our targets to reduce emissions for all five key pollutants in the latest reporting year."