SoICanBreathe is a week of BBC stories exploring some of the different ways people are seeking to make the air cleaner.
We asked you to tell us about what steps or suggestions you had for making a difference to air pollution.
Farhad Ahmad, 25, from the Ahmadiyya Muslim Youth Association in London, said the group had planted 175,000 trees in 16 areas across the UK.
“Looking at the figures, the 20,000 trees planted in the last four months, are equivalent to adding about 1,000 tonnes of oxygen and taking about 4,000 tonnes of carbon dioxide from the air,” said Mr Ahmad.
A study by Dr David Nowak, senior scientist at the US Forest Service, has shown that trees only reduce urban air pollution by up to 1%. Yet even this small reduction can have huge health benefits.
“Using plants to absorb pollution definitely helps with air quality,” said Tim Pryce, head of public sector at the Carbon Trust. “However, they do not have anywhere near the same impact as reducing the sources of pollution.”
If you would like to plant a tree here are some tips.