Last February the local government in Tehran announced the closure of all the city’s schools in an attempt to protect children from the increasingly deadly air in the Iranian capital.

A fog had set in over the city trapping pollution over the city making it dangerous for vulnerable people to go outside. Iran’s Supreme Leader Khamenei even made a rare intervention declaring that driving in severe pollution was not permissible without a valid reason.

Belatedly the government has started to act, cracking down on more polluting cars, spending more on public transport and encouraging businesses that go green.

Tehran has become one of the world’s most congested, polluted cities in the world, joining other Asian and African megacities in a roll call of public health disasters.

Air pollution is now the fourth biggest cause of death globally, primarily affecting people in Africa and Asia rather than the west. The rise of the motor car in newly affluent China and emerging Asia has created cities which are choked on pollutatants, including so called “super pollutants” such as black carbon, methane, hydrofluorocarbons and tropospheric ozone. As well as causing death through asthma, heart failure and cancer air pollutants are also a major factor in climate breakdown.

The failure of policy makers to deal with this disaster can be primarily attributed to the fossil fuel lobby and car manufacturers who have a vested interest in selling vehicles and using coal and oil to produce energy.

Failure to change this will lead to growing costs in terms of health care as well as economic inefficiencies thanks to long commuting times and increasingly unliveable cities designed for cars rather than people.

What makes this explosion in air pollution frustrating is that the solutions are already exist. But the political will required to implement the policies is missing.

Governments in emerging economies are often short on resources and face overwhelming problems which pushes public health to the back burner, this along with pressure from the fossil fuel and car lobbies make change extremely difficult.

There is huge opportunity for investment in public transport, electric cars and non car focussed infrastructure. The potential gains are huge in terms of public health, carbon emission reductions not too mention creating an improved quality of life in terms of less congestion, noise and road traffic accidents. The rise of renewable energy technology and new government policies to encourage their take up gives hope that cities can transition away from fossil fuel usage.

Tehran is just one city suffering from pollution, the rise of mega cities in emerging economies allied with rising incomes has seen out of control pollution in cities such as Cairo, Delhi and Baghdad.

Wealthier inhabitants can use air purifiers and face masks in an attempt to mitigate the pollutants, others will have to wait until serious government action is taken before they see any improvements.