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Gujranwala is a city in the Punjab region of Pakistan, famous for its cuisine and also known as the ‘city of wrestlers’ locally. It is the 3rd largest industrial center in the country after Faisalabad and Karachi, and is part of the so called ‘golden triangle’ pertaining to industrialized cities with an emphasis on product export. The other two cities that make up this triangle are Sialkot and Gujrat.
In regards to its pollution levels, Gujranwala came in with a PM2.5 reading of 105.3 μg/m³, putting it into the higher end of the ‘unhealthy’ ratings bracket, a classification that requires any reading between 55.5 to 150.4 μg/m³, making it essentially a very undesirable rating for any country or city that falls into it, as the name suggests.
This reading of 105.3 μg/m³ put Gujranwala into 1st place out of all cities ranked in Pakistan in 2019, as well as 3rd place out of all cities ranked worldwide. This is an extremely polluted situation to be in, meaning that the air in Gujranwala would be heavily permeated by smoke, haze and all types of chemicals and fine particulate matter, making the air quality not only very poor but hazardous for all sections of the population.
Gujranwala would have many different polluting sources, all of which would come together to compound the situation further, with both man made pollution as well as geographical and meteorological factors (particularly during the colder months) playing a role in its excessively high PM2.5 ratings.
One of these sources would be the excessive use of vehicles, with cars, rickshaws and motorbikes all adding to the pollution along with heavy duty vehicles such as trucks, lorries and buses, many of which run on diesel or other unclean fuel sources, putting out far larger amounts of pollution than is considered safe.
Other causes of pollution would be from factory and industrial emissions, both on a large and small scale, with locally run brick kilns putting out heavy amounts of smoke along with major factories that contribute their own fossil fuel based pollution alongside whatever unique chemical effluence comes from the manufacturing of their products. Many factories in Gujranwala and indeed the whole Punjab province have been targeted in recent years for their excessive contribution to pollution levels.
Lastly, other sources would include ones that create dust based pollution, such as construction sites and road repairs, with poorly maintained construction sites being a major contributor to dust buildups within the city, allowing large amounts of material such as ground silica, gravel and concrete dust to be released into the atmosphere.
Observing the data taken over 2019, the months that came in with the highest levels of pollution were at the very beginning and end of the year, with the ‘cleanest months’ coming in during the mid-portion of the year, albeit still with excessively high readings of PM2.5.
The rise in pollution became apparent around September, and continued to rise rapidly from there at an alarming rate, with September coming in at 67.4 μg/m³, and then rising every month until it hits a high in December with a reading of 217.3 μg/m³.
This would no doubt continue on until January of the next year, with 2019’s January also coming in with the highest reading of pollution out of the entire year, with a highly elevated number of 220.4 μg/m³ being detected, putting it into the top end of the ‘very unhealthy’ bracket, (150.5 to 250.4 μg/m³ for classification), verging on going up into the highest ratings bracket of ‘hazardous’ (any reading greater than 250.4 μg/m³).
This is a rare occurrence for any city around the world to have readings of pollution this high, and would cause some severe health issues for those caught living within such conditions.
As mentioned briefly before, Gujranwala sees its cleanest air quality in the middle portion of the year, with June through to August coming in with the best levels of PM2.5, although of note is that despite them being the cleanest readings in Gujranwala, by international standards they would still represent a serious hazard to health and a sign that the air quality in Gujranwala is indeed detrimental to its citizens year round.
The readings taken in June through to August were 53.3 μg/m³, 59/2 μg/m³ and 48.8 μg/m³ respectively, making August the cleanest month out of the entire year and its reading putting it into the "unhealthy for sensitive groups" bracket, which requires a PM2.5 reading of anywhere between 35.5 to 55.4 μg/m³ to be classed as such.
With pollution sources such as vehicles, factories, brick kilns, open burn areas and poorly maintained construction sites all contributing heavily, particulate matter and chemical compounds typically released from such sources would be ones such as nitrogen dioxide (NO2) and sulfur dioxide (SO2) coming directly from exhaust fumes (as well as any combustion of fossil fuels such as coal, as would be used in factories).
Nitrogen dioxide is released very prominently from vehicles, often found in high quantities over areas that see high volumes of traffic, so much so to the point that high readings of nitrogen dioxide are often an indicator that any given area is seeing excessive amounts of vehicles passing through it.
Other pollutants that may arise from the open burning of rubbish and other waste (as well as wood and any organic material) would include carbon monoxide (CO), an odorless and colorless gas that is particularly dangerous when it builds up in poorly ventilated areas, often directly responsible for deaths at home due to its release from a source such as a badly maintained boiler or other similar appliance. Others are black carbon, a fine particulate matter that makes up the majority of soot and has highly carcinogenic properties when inhaled.
Beyond having cancer causing properties, black carbon (and other fine particulate matters such as silica or gravel dust), when possessing a certain minuteness of size (2.5 micrometers or less in diameter) have the ability to cross the blood barrier in the lungs and wreak havoc on the body via the circulatory system, causing damage to the blood vessels, heart, liver, kidneys, reproductive system and as well as the lungs where they entered.
These are but a few of the many pollutants found in the air in Gujranwala, with others such as volatile organic compounds (VOC’s) like benzene and formaldehyde permeating the air, as well as furans, dioxins, polychlorinated biphenyls and dangerous metals such as lead, mercury and cadmium all being present.