The Frome and Somerton MP David Warburton writes:

Since lockdowns first began, snatching a breath of fresh air in a local green space has become a glorious escape. A moment to reconnect with the real world. To exercise and, when possible, to meet up with friends in a Covid-secure way.

Yet, for many of us, that lungful of air isn't so fresh. Astonishingly, air pollution is now the leading environmental threat to human health in the UK. Cleaning it up is an imperative, and we now have that opportunity through the new Environment Bill.

This Government leads the way internationally in its efforts to tackle air pollution. The Clean Air Strategy was described by the World Health Organisation as 'an example for the rest of the world to follow', and the Strategy indeed took the world by the hand to lead by example: from making sure new wood-burning stoves are cleaner and more efficient, to supporting farmers to use low-emission equipment.

But, as we learn more about the impact of air pollution on our health, it's clear the job isn't done. Dirty air causes between 28,000 and 36,000 deaths every year, and last year the inquest into the death of 9 year old Ella Kissi-Debrah ruled that toxic air from traffic was a cause of death, the first such ruling in the UK. If current levels persist, we're estimated to see 2.5 million new cases of related health conditions such as asthma, strokes and heart disease. UNICEF calculates that one in three children in the UK are currently growing up exposed to illegal levels of pollutants.

And as well as the harm to individuals, the wider effect on public services and the economy is staggering. In total, air pollution is estimated to cause six million sick days each year and has a total social cost of £22.6 billion. Little wonder that two thirds of the public say they're unwilling to return to pre-lockdown levels of pollution, having recently inhaled something noticeably cleaner.

Addressing this problem will need both local and national action. One local measure, proven effective, has been 'school streets'. This involves discouraging cars from the road directly outside schools at pick-up and drop-off times, while encouraging more pupils to walk, cycle or jump on the bus. And it's been demonstrably effective, helping protect children from the effects of air pollution where they study and play. Of course, it can't work for the geography or logistics of every school, but when implemented in partnership with parents and teachers, such schemes – and the improved conditions they've brought - have been very popular. Councils ought to start exploring these partnerships now and bid into the Government's £2 billion walking and cycling fund to get them set up.

But national action is also needed. The landmark Environment Bill, which I hope will pass into law early in this new parliamentary session, places the environment at the centre of decision making across government. An indispensable part of the bill focusses on reducing air pollution: not least the setting of an ambitious, legally-binding target to reduce fine particulate matter (PM2.5), the most harmful type of air pollution.

Now I'm urging the Government to even further, and to act on the recommendation of the coroner following the inquest into the Ella Kissi-Debrah's death, by enhancing the Bill to enshrine in legislation the World Health Organisation's current guideline limits on PM2.5. in line with the campaign by the Chair of the Defra Select Committee, Neil Parish MP.

Make no mistake, this isn't just about breathing in noticeably cleaner air. The health benefits from hitting that WHO target would be worth £6.8 billion per year. And that's without considering the costs to the NHS and social care system from air pollution-related illnesses which we could avoid.

In December the Prime Minister made the UK the first G7 nation to commit to phase out the sale of new petrol and diesel cars by 2030. This won another decisive battle in the war against polluted air. I hope we build on our global environmental leadership by accepting the amendment and paving the way to us all being free to truly enjoy our green spaces. In fresh clean air.