Milan drivers face trend-setting pollution charge

The fee will be measured on pollutants emitted by vehicles, based on five engine classes.

Drivers must pay between 2 and 10 euros ($3-$15) during weekday daytime hours to drive in the congested inner city, an area of just over eight square km (three square miles).

Cameras at 43 electric gates will monitor vehicles to ensure they have paid, or to levy fines of 70 euros and more. Estimated revenue of 24 million euros this year is earmarked for buses, new bicycle paths and green vehicles.

Milan is often shrouded in haze and its residents often complain of sore throats and itchy eyes from pollution.

Many European cities are struggling to meet EU limits on fine particulate matter, a major cause of respiratory illnesses. Milan estimates the charge will cut the pollutant in the area by almost a third.

Vehicles using alternative power such as methane and electricity as well as ambulances, motorcycles, buses, taxis and vehicles delivering perishable goods will be exempt. Residents of the zone can seek a discount.

Some critics argue that the pollution charge should not just be an extra tax on drivers. Others want wider action.

"Car exhaust is an important source of particulate matter but it's not the only one," Guido Giuseppe Lanzani, head of the air quality department at Lombardy's regional environmental protection agency, told Reuters. (Writing by Antonella Ciancio, Editing by Keith Weir)