The prevalance of particles with a diameter of less than 10 microns were reported by regional air monitoring centres in the affected areas.
On Tuesday The Local reported how environmental campaigners said the pollution levels in the French capital had reached such high levels that people's lives were being put in danger.
Ecology without Borders (Écologie sans Frontière), Breath (Respire) and Unity for the Planet (Rassemblement pour la Planète) have lodged a legal complaint in Paris, on the grounds that pollution levels are endangering people’s lives.
“We are sick of this air pollution,” Nadir Saifi, spokesman of Ecology with Borders told France Info. As soon as the weather is good, and as soon as it's dry in winter you have these peaks in pollution and the emergency wards at hospitals fill up. Slogans and small demonstrations are no longer enough.”
What has caused the spike in air pollution?
- A lack of wind, coupled with cold nights followed by balmy days, has contributed to the severe air pollution.
- At night, the ground cools down while the atmosphere heats up during the day due to the sun, which means polluting particles emitted by cars or heating become stuck under a warm layer of air and cannot rise up or be blown away.
- As a result, monitoring centres have reported a particularly strong concentration of particles with a diameter of less than 10 microns - so-called PM10 particles - in the air.
- Pollution alerts are issued in France when the concentration of these small particles reaches or breaches 80 micrograms per cubic metre.
- PM10 particles are highly monitored as the smaller and lighter a particle is, the longer it stays in the atmosphere and can remain suspended for weeks.
- Particles less than 2.5 microns in diameter are also the most dangerous to health as they can penetrate deep into the lungs and the blood system. They can also lead to asthma, allergies and respiratory ailments.
Alerts have been declared in Haute Normandie, Pas de Calais and Calvados in the north, the Ile-de-France region where Paris is located and the centre-east including some Alpine areas and in some parts of the west.
Alerts are issued in France when the concentration of small particles reaches 80 micrograms per cubic metre.
Measures to fight the advanced pollution level include orders to drive vehicles slowly, a ban on chimney fires and an advice to residents to eschew physical activity either indoors or outdoors.
Airparif, an official monitor and a federation of regional watchdog for air pollution in France, said the pollution threshold would be breached on Thursday in the Paris region.
Authorities in the capital reacted by announcing that the Velib' bike sharing scheme and its car version Autolib' would be free from Thursday.
The levels of PM 10 - or small particles which easily penetrate the lungs - were reported at 50 micrograms per cubic metre in several areas such as Brittany, the Loire region and parts of wine-producing Burgundy.