Scientists have discovered that Athens, one of Europe's most polluted cities, has seen a drastic reduction in pollution since 2008.

They claim a drop in air pollutants such as nitrogen oxides and sulphur dioxide of up to 40 per cent is a direct result of the financial crisis gripping Greece.

Now in its sixth year of recession and reliant on international bailouts, austerity measures have taken a heavy toll on poorer sections of society.

More than three-and-a-half million vehicles are registered in the nation's capital, and almost half of Greece's population live in and around Athens.

But with cuts forcing many families to adopt belt-tightening measures and fuel prices continuing to rise, fewer are choosing the use their cars, helping to clean up the city's skies.

The European authors of the study, who tracked pollution levels using satellite readings, also found that up to 30 per cent of small-scale industry in the region has shut down, contributing to a reduction in emissions.

In their report, submitted to journal Geophysical Research Letters, the researchers found: 'The strong correlations between pollutant concentrations and economic indicators show that the economic recession has resulted in proportionally lower levels of pollutants in large parts of Greece.'

Dr Mihalis Vrekoussis, a research scientist at The Cyprus Institute who led the study, and his team concluded that: 'The economic crisis in Greece from 2008 and onward resulted in a reduction of anthropogenic activities emitting gaseous pollutants to the atmosphere.

'Observations derived from three different satellite instruments revealed a large reduction, about 30 to 40 per cent in the tropospheric NO2 vertical columns observed over Athens as well as decreases over other densely populated regions of Greece, like Thessaloniki.'

But late last year, experts warned of a surge in air pollution in the Greek capital as people burnt wood to heat their homes.

Particulate matter has been measured at 150 milligrammes per cubic metre - three times normal danger levels – in parts of the city, the nation's environment ministry said.

'The smog, which appears especially in the evening, is made up of polluting and dangerous particles that can cause respiratory problems,' said Evangelos Gerassopoulos, director of the Environment Institute of the Athens Observatory.

'This polluting cloud is the result of the combination of a lack of wind and the burning of wood, which is more prevalent than usual because of the high price of domestic heating fuel.'