Bloomberg - Authorities in Iran have shut down schools in eight provinces including the capital Tehran because of high levels of pollution, the semi-official Iranian Students’ News Agency reported.

Schools and universities in Iran’s third-largest city, Esfahan, and its wider province, have also been closed. Other regions affected are Alborz, Eastern Azerbaijan, Bushehr, Qazvin, Markazi and Qom, according to ISNA, which cited officials in each province.

In the past 24 hours, some 1,500 people have been hospitalized and received emergency care because of respiratory problems related to toxic air, ISNA reported, quoting Mojtaba Khaledi, spokesman for Iran’s National Emergency Organization. Khaledi advised children and the elderly to avoid going outside in the affected cities.

It’s the third time in less than a month that schools in Tehran have been shut due to toxic air and high levels of particulates. While seasonal smog and pollution levels in Iran affect the capital and other big cities every year during the winter months, it’s rare for dozens of cities to enforce school closures at the same time.