Tackling climate change by cutting greenhouse gas emissions could save millions of lives because of the cleaner air that would result, according to a recent study.

Researchers predict that, by 2050, about 100 million premature deaths caused by respiratory health problems linked to air pollution could be avoided through measures such as low emission cars. The economic benefits of saving those lives in developing countries such as China and India could also strengthen the negotiating hand of the UK and Europe at a crucial UN climate summit in Copenhagen this December.

Johannes Bollen, one of the authors of the report for the Netherlands Environment Agency, said the 100 million early deaths could be prevented by cutting global emissions by 50% by 2050, a target consistent with those being considered internationally.

The reports warns that if governments continue with business-as-usual energy use, then population growth, ageing demographics and increased urbanisation will cause premature deaths from pollution to increase by 30% in OECD countries, and 100% outside the OECD.

The study also has implications for which technologies are chosen to reduce CO2 and other greenhouse gases. The study points out that while carbon capture and storage technology can capture CO2, it does not usually trap other air pollutants. Last month, the energy and climate minister, Ed Miliband, put "clean coal" at the centre of UK energy policy by pledging no new coal-fired power stations would be built without at least partial CCS.

In contrast, the report said, reducing car emissions and the number of vehicles on the road would lead to both lower greenhouse gases and fewer local air pollutants from exhausts. Jim Storey, air quality policy adviser at the UK's Environment Agency, said he wanted climate policies that account for their effect on air pollution: "There are win-wins for climate change and air quality that should be pursued with all haste, such as improving energy efficiency in houses, and reducing emissions from transport. Transport remains the largest cause of air pollution in the UK, and accounts for around 20% of the UK's greenhouse gas emissions."

The report also said the economic gains of cleaner air could be attractive for developing countries during climate treaty negotiations in Copenhagen later this year. By not losing people of working age to pollution, India and China, for example, stand to gain 4-5% in GDP in 2050 as a result of cleaner air, compared with around 1% of GDP in OECD countries such as the UK. "The local air pollution benefits of climate mitigation policies provide an additional economic incentive for countries to participate in a global agreement to mitigate greenhouse gas emissions," said Bollen.

The health threat of air pollution is well known. Recent research from the American Lung Association revealed that 186 million US residents live in areas with dangerous levels of air pollution. "Despite almost 40 years since the Clean Air Act passed in 1970, six in 10 Americans still live in dirty air areas, areas where the air is unhealthful to breathe," said the ALA's Paul Billings. As well as citing dirty diesel vehicles and coal power plants as significant contributors to US air pollution, the Association's report called for a clean-up of cruise ships, container ships and tankers, which it said will be responsible for approximately 45% of US particulate emissions by 2030. Confidential data released last month from the shipping industry suggested 15 of the world's biggest ships may now emit as much pollution as all the world's 760m cars.

In the UK, a report published this month by the London Assembly Environment Committee claimed that poor air quality in London may have contributed to 3,000 premature deaths in the capital in 2005. London has the worst air quality in the UK and among the worst in Europe for small, sooty particles known as PM10s and nitrogen dioxide.

The key air pollutants that can harm human health include nitrogen dioxide, sulphur dioxide, volatile organic compounds, ammonia and particulate matter and are produced by burning fossil fuels in power plants and vehicles. Children and the elderly, plus people with respiratory conditions such as asthma, are particularly at risk.