Mexico City shuts schools due to high air pollution

Public and private schools around Mexico City closed Thursday as a precautionary measure against elevated levels of pollution.

The Miexico City metropolitan area is home to more than 20 million people and children are recommended to avoid exercise and using contact lenses. People are suggested to say indoors, if possible.

The National Polytechnic Institute and National Autonomous University of Mexico (UNAM) said would be suspending classes on Thursday.

The authorities meanwhile declared Tuesday an environmental emergency due to reduced visibility caused by ash and smoke in the air.

President Andres Manuel Lopez Obrador said the pollution in Mexico City metropolitan area is highly regrettable.

For days the city has been wrapped in a smoky haze. Particulate matter measuring 2.5 micrometers reached 158 micrograms per cubic meter of air on Tuesday morning. It is more than six time than what is recommended by the World Health Organization.

In the late 1990s air pollution levels in the city dropped but in recent years increase has been measured.

Meanwhile, the most polluted city in the world is Peshawar of Pakistan and least polluted is Simak of Turkey.