ten cities in the us have dramatically improved their air quality, with ozone levels registering a reduction from 75 per cent to 40.7 per cent.

The hallowed list includes Rochester, New York, Buffalo, Newark, Milwaukee, San Diego, Boston, Sacramento, Detroit, Chicago, New Jersey and Los Angeles. "People in these cities should be proud that their efforts are paying off. This proves that we can accomplish air quality goals when we work together,' said William Fay, president, Foundation for Clean Air Progress ( fcap), an ngo.

Data from the us Environmental Protection Agency (epa ) was used to compile the list of cities that have made significant progress in cleaning up their air in the past 10 years.

The progress seen in the top 10 cities reflects improvements in national air quality, according to a recent report conducted for fcap by Tech Environmental Inc, an environmental consultancy firm in Waltham, Massachhussets.

The us has experienced one-third reduction in pollutants since 1970 and more than 77 million tonnes of pollutants were eliminated from the air per year, according to the report.

Reductions in emissions of pollutants include carbon monoxide, nitrogen oxides, volatile organic compounds, particulate matter and lead.

"We need to spread the word about how much cleaner the air has become. Too many people are under the false impression that their air quality is getting worse from what it was yesterday, rather than better.

"When people are aware of what's possible, they are far more motivated to pitch in and help to keep the process going,' added Fay.