The deteriorating air quality in cities is a matter of grave concern. The United States Environmental Protection Agency regards air quality satisfactory if the AQI is under 50. As per the index, Lahore reported a particulate matter (PM) rating of 423. Pakistan's financial capital Karachi ranked at 7 on the AQI. The AQI is a yardstick that runs from 0 to 500. The higher the AQI, the greater the level of air pollution, and thus higher the health risk.
An AQI of 0–50 (Level 1) is deemed excellent as there are no health implications. Everyone can continue their outdoor activities normally.
An AQI of 51–100 (Level 2) is considered good as some pollutants may slightly affect very few hypersensitive individuals. Only very few hypersensitive people should reduce outdoor activities.
An AQI of 101–150 (Level 3) is considered slightly polluted and healthy people may experience light irritations. However, sensitive individuals will be slightly affected to a larger extent. Children, seniors, and individuals with respiratory or heart diseases should reduce sustained and high-intensity outdoor exercises.
An AQI of 151–200 (Level 4) is a case of moderate pollution. Sensitive individuals will experience more serious conditions. The hearts and respiratory systems of healthy people may be affected. In these circumstances, children, elderly and individuals with respiratory or heart diseases should avoid sustained and high-intensity outdoor exercises. General population should moderately reduce outdoor activities
An AQI of 201–300 (Level 5) is deemed to be a case of heavy pollution. Healthy people will commonly show symptoms. People with respiratory or heart diseases will be significantly affected and will experience reduced endurance in activities. Children, seniors and individuals with heart or lung diseases should stay indoors and avoid outdoor activities. General population should reduce outdoor activities.
An AQI of 300 and beyond (Level 6) means the air quality of a particular locality is severely polluted. Healthy people will experience reduced endurance in activities and may also show noticeably strong symptoms. Other illnesses may be triggered in healthy people. Elders and the sick should remain indoors and avoid exercise. Healthy individuals should avoid outdoor activities.
Air pollution is an emerging environmental issue in the big cities of Pakistan. Dust and smoke particles in Pakistan are generally twice the world average and five times higher than in the developed world. The biggest causes of pollution are fossil fuel-burning power plants and cars. Combined, these two sources are responsible for about 90% of all air pollution. The most serious issue relating to air pollution in Pakistan is the presence of excessive Suspended Particulates Matter (SPM). The big sources of SPM are vehicles, industry, burning of solid waste, bricks kilns and natural dust. Every day, each person inhales about 20,000 litres of air. With every breath, people risk breathing dangerous chemicals. Lahore’s air pollution is caused largely by vehicle and industrial emissions, smoke of burning garbage and crop residue and dust from construction sites.
According to The Telegraph, these are the world's 20 most polluted cities and their respective AQI: Peshawar (540), Rawalpindi (448), Kanpur, India (319), Hamad Town, Bahrain (318), Faridabad, India (316), Delhi, India (292), Karachi (290), Gaya, India (275), Patna, India (266), Varanasi, India (260), Ma’ameer, Bahrain (257), Lucknow, India (255), Riyadh, Saudi Arabia (251), Ras Hayyan, Bahrain (250), Nabih Saleh, Bahrain (244), Muzaffarpur, India (221), Islamabad (217), Narayanganj, Bangladesh (205), Lahore (198), and Ulaanbaatar (197).
Moreover, farm fires have been an easy way to get rid of paddy stubble quickly and at low cost for several years. With the use of combine harvesters, the practice became more common as the harvester leaves behind tall stalks, which have to be removed before replanting. The paddy straw and stalks have high silica content and are not used to feed livestock. The easiest, but the least productive way to get rid of it is to set it on fire. Every October and November, contaminates in the air in Punjab province shoot up as farmers burn rice stalks left behind after harvesting. They do so to clear their fields to plant wheat.
During these cooler months, the provincial capital Lahore, which is surrounded by rice-growing districts, is covered with thick smog. “It is a health emergency – the air quality monitors in Lahore routinely show hazardous levels in November,” said Farah Rashid, a climate and energy programme coordinator for green group WWF-Pakistan. Now the Punjab government hopes to tackle the problem by providing 500 rice farmers around Lahore with a set of machines that together eliminate the need to burn crop stubble. The Environment Protection Department has fined farmers who burn crop stubble – a traditional practice – and is looking at promoting zero tillage farming as an alternative, though making the switch will be costly for farmers, Aslam admitted. The government has also pushed brick kiln owners to shift to cleaner technology, offering loans to make the switch, as well as issuing fines for kilns that operate using the dirtiest technologies, such as burning used tires. Additionally, the government is considering to set higher emissions standards for vehicles – but warned the switch could make petrol "more expensive for consumers as a result", Aslam said.
The Environmental Protection Department said the level of smog pollution was lower this year than previous year in Lahore because of anti-smog measures already underway. Abid Omar, who founded the Pakistan Air Quality Initiative, a non-profit group that publishes data about air pollution and its health impacts, agreed that a broad approach is needed. "We have to reduce air pollution at the source, be it industry, agriculture, urban waste or transportation. This will require time, money and planning," he admitted.