By Rob Chantrey –
In 2018 alone, 8.7million people died from fossil fuel-driven air pollution, equivalent to 20% of deaths worldwide [1]. This is not an anomaly. Every year millions globally, in both developing and developed countries, die at the hands of the ‘invisible killer’. Despite an increasing number of discoveries identifying smog’s impacts on human health, we are still discovering the extent of these short-term or long-term impacts. Ali et al. (2018) investigates the cause of air pollution and smog’s effect on human health.
Figure 1: Sulphurous smog surrounding Nelson’s column London, 1952. Image: N T Stobbs from Wikimedia commons
Smog is the combination of natural fog with industrial smoke and other chemical pollutants. There are two types:
- Sulphurous smog- formed by large concentrations of sulphur dioxide produced during combustion of fossil fuels, especially coal, creating an acidic fog. One such event, the great London smog of 1952, resulted in the deaths of 12,000 people [3] as well as debilitating countless others.
- Photochemical smog- is generated by chemical transformation of vehicular pollution particularly nitrogen dioxide, ozone and particulate matter smaller than 2.5microns (PM5).
The article highlights its impact on human health by asking people about their experience of smog [2].
- 83% of respondents found their body condition had deteriorated due to smog
- 87% developed a cough or throat infection
- 41% found breathing harder
- 31% had worsening asthma
- 30% found they had developed skin diseases
Further studies have linked PM2.5 exposure, a significant component of smog, to an increased risk of developing cardiopulmonary disease such as lung cancer and increases the mortality of an individual [6]. Furthermore, exposure is linked to increasing incidence of cardiovascular disease [7]. Recent studies have also discovered that increased exposure results in an increased risk of developing dementia [8]. Moreover, smog results in a decrease in quality of life due to increased disease prevalence. Consequently, it is evident that smog and air pollution have a detrimental impact on human health.
Figure 2: Photochemical smog seen over Harbin, China in 2012. Image: Fredrik Rubensson from Wikimedia commons
The article highlights Pakistan’s air pollution. The problems relate to pollution produced by transportation, industry in major cities and agricultural practices like stubble burning. Lahore, the 2nd largest city in Pakistan, is officially the most polluted in the world, with PM2.5 concentrations regularly 5x the WHO safety limit [9], whilst Karachi is similarly hazardous. An estimated 128,000 deaths in Pakistan and 1 in 10 deaths in under-fives result from air pollution [9], signifying its seriousness. Pakistan’s air pollution mortality rate, like many other countries globally, highlights the importance of significantly reducing concentrations of manmade pollutants.
Ultimately, the research conducted by Ali et al. (2018) shows the health impacts of smog and air pollution on a given population, and the necessity for change in pollution management in order to reduce its environmental and human impacts. This is further supported by articles providing evidence for its influence in the long-term deterioration of human health. Without a global, cooperative response to tackle the issue, both humanity and the environment will suffer the long-lasting consequences of air pollution.
References and further reading
[1] Milman, O. (2021). “Invisible killer”: fossil fuels caused 8.7m deaths globally in 2018, research finds. The Guardian. [online] 9 Feb. Available at: https://www.theguardian.com/environment/2021/feb/09/fossil-fuels-pollution-deaths-research [Accessed 2 Dec. 2021].
[2] Ali, Y., Razi, M., De Felice, F., Sabir, M. and Petrillo, A. (2019). A VIKOR based approach for assessing the social, environmental and economic effects of “smog” on human health. Science of The Total Environment, [online] 650 (Part 2), pp.2897–2905. Available at: https://www.sciencedirect.com/science/article/pii/S0048969718339147 [Accessed 2 Dec. 2021].
[3] Bell, M.L. and Davis, D.L. (2001). Reassessment of the lethal London fog of 1952: novel indicators of acute and chronic consequences of acute exposure to air pollution. Environmental Health Perspectives, 109 (suppl 3), pp.389–394.
[4] Stobbs, N.T. (1952). Nelson’s Column during the Great Smog of 1952. Wikimedia Commons. Available at: https://commons.wikimedia.org/wiki/File:Nelson%27s_Column_during_the_Great_Smog_of_1952.jpg [Accessed 2 Dec. 2021].
[5] Rubensson, F. (2012). An image depicting the heavy levels of smog in Harbin, China. Wikimedia Commons. Available at: https://commons.wikimedia.org/wiki/File:HarbinChinaSmog_121226.jpg [Accessed 2 Dec. 2021].
[6] Pope III, C.A. (2002). Lung Cancer, Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air Pollution. JAMA, [online] 287(9), p.1132. Available at: https://jamanetwork.com/journals/jama/fullarticle/194704[Accessed 2 Dec. 2021].
[7] Hu, D. and Jiang, J. (2013). A Study of Smog Issues and PM2.5 Pollutant Control Strategies in China. Journal of Environmental Protection, [online] 04(07), pp.746–752. Available at: https://www.scirp.org/html/11-6701887_34944.htm?pagespeed=noscript [Accessed 2 Dec. 2021].
[8] Bishop, K., Ketcham, J., Kuminoff, N., Banzhaf, S., Carson, R., Deryugina, T., Deschenes, O., Jessoe, K., Greenstone, M., Kelly, D., Krupnick, A., Mcfadden, D., Murphy, A., Schechter, L., Barbara, S. and Workshop, O. (2018). NBER WORKING PAPER SERIES HAZED AND CONFUSED: THE EFFECT OF AIR POLLUTION ON DEMENTIA We Are Grateful for Insights and Suggestions from. [online] National Bureau of Economic Research, p.44. Available at: https://www.nber.org/system/files/working_papers/w24970/w24970.pdf [Accessed 2 Dec. 2021].
[9] Welle (www.dw.com), D. (2021). Why Pakistan Has Some of the Most Polluted Cities in the World | DW | 01.11.2021. [online] DW.com. Available at: https://www.dw.com/en/why-pakistan-has-some-of-the-most-polluted-cities-in-the-world/a-59686579[Accessed 2 Dec. 2021].
