Air pollution could shorten a child's life by up to seven months, a study on Birmingham has suggested.
Researchers at Kings College London have found that an eight-year-old child in Birmingham born in 2011 may die between two to seven months early if exposed over their lifetime to projected future pollution concentrations.
It is the first time new Government guidance on "mortality burdens" of air pollution has been applied in practice in a large city area.
The study looked at the combined impact of two pollutants - particulate matter and nitrogen dioxide - two of the leading causes of poor health from air pollution.
The impact was considered to be worse than some other major cities in the UK - with the report finding a higher loss of life expectancy in Birmingham than Manchester.
The study calculated the annual health cost of air pollution in Birmingham as between £190 million to £470 million per year.
Local leaders are calling for clean air zones to be established in major cities across the country.
Polly Billington, director of the UK100 network, which commissioned the research, said:
A spokeswoman for the Department for Environment, Food and Rural Affairs said:
The NHS says it welcomes the call for action.