Elevated ozone levels in the Var

Copyright: Chris Keating

The Environment Agency AASQA sounded the alarm after recording 240 micrograms of poisonous ozone gas in (cubic) air around the region.

When sitting in the Earth's upper atmosphere, the oxygen-based gas, ozone, is beneficial since it blocks ultraviolet rays from the sun. However, closer to home, it is harmful when inhaled at sufficiently high concentrations and is a component of the toxic air pollution that sometimes plagues large regions like the Côte d’Azur.

As a result, the Alpes-Maritimes authorities earlier today issued traffic limits on all motorways, reducing speed limits for vehicles to a maximum 100 kilometres per hour.

These restrictions were announced on electronic billboards. There were also written notices being sent out to industrial companies with high pollution rates.

Residents were advised that such bad weather conditions would hamper sports and physical outdoors activities.

Under the Gard decree signed in 2004, regional and local authorities in France have the right to issue emergency measures to bring down CO2 emissions, which contributes to air pollution in cases of high risk.

Ozone facts

Ozone is sometimes mistakenly thought of as being healthy, possibly because it is sometimes used as a disinfectant to kill germs. However, this is not true.

Breathing air with small dozes of ozone leads to a number of health problems. Immediate effects include throat and lung irritation, and prolonged exposure can cause permanent reduction in lung functions.

For this reason, it is very hard to pinpoint acceptable levels of ozone exposure, although levels around 200 micrograms per cubic meter of air appear to cause some substantial health effects.

Ozone gas can be produced through chemical reactions of air pollutants with sunlight and also by electrical discharges in air.

If the ozone levels don not decrease by tomorrow then there is a possiblity the bans will continue to the end of this week.

AA