LAHORE: Lahore was ranked the world’s most polluted major city on Wednesday morning as smog thickened over the city with the onset of colder weather.

In the past few years, air pollution has become one of the most pressing public health and environmental crises facing Pakistan. Various cities of the country, most notably Lahore, deal with smog, especially in the winter months. The phenomenon is attributed mainly to industrial emissions, vehicular pollution, stubble burning and air movement.

According to the live air quality ranking published by Swiss air quality monitoring platform IQAir, Lahore recorded an Air Quality Index (AQI) of 296 at 10am on October 28, placing it at the top of the list of the world’s major cities.

Cairo ranked second with an AQI of 289, followed by Delhi at 272. Tashkent stood fourth with an AQI of 186, while Karachi ranked fifth at 173, according to the ranking.

The readings placed Lahore and Cairo in the ‘very unhealthy’ category under the US AQI scale, while Delhi’s air quality was also in the same category.

An AQI reading of 296 indicates a high level of air pollution that can pose health risks, particularly for children, older people and those with respiratory or heart conditions.

The worsening air quality coincided with colder conditions in Lahore during the early morning, when smog reduced visibility and added to concerns over the city’s deteriorating air quality.

Residents were advised to limit prolonged outdoor exertion when pollution levels were high, particularly those with asthma and other respiratory conditions.

Environment Protection Agency (EPA) spokesperson Sajid Bashir told Dawn that the authorities were monitoring industries and had installed devices to record pollution levels.

He said changing weather conditions were contributing to smog, adding that measures were being taken to prevent stubble burning.

Easterly winds had been consistently pushing polluted air from India’s border regions into Lahore, worsening the smog situation across central Punjab, he said.

The government was procuring and installing 30 more modern fog cannons mounted on electric trucks to combat severe smog and air pollution, Bashir said.

Anti-smog guns were being deployed on a priority basis in areas where higher pollution readings were recorded, particularly at locations with elevated levels of PM10 (particulate matter), he added.

He said the machinery was being used to suppress dust on roads and in surrounding areas to limit its spread.

“Development work in Lahore and other cities of the province was also contributing to pollution,” he added.

Bashir said measures were being taken to combat smog, but the process would take time. Punjab Climate Watch was working in three shifts to monitor industries in Lahore, with teams inspecting violations, registering cases and imposing fines.

Last week, Lahore ranked as the world’s most polluted city, with its air quality classified as “hazardous”.

On Oct 2, Lahore also topped IQAir’s list of the world’s most polluted cities, with an AQI of 167, classified as “unhealthy”. At the time, CM Maryam said the government was making efforts to address environmental issues.

On Oct 1, a new analysis released by the European Union’s Copernicus Climate Atmosphere Monitoring Service (CAMS) ranked Lahore among cities whose ozone levels were “extremely poor”.