Hello everyone! Last post, Lee Yang and I concluded by defining air pollution as “The introduction of contaminant(s) that, through physical, chemical or biological processes, cause(s) or result(s) in deterioration of human health and/or quality of life”. Before we begin comparing it with the legal definitions, let us briefly explain the changes we have made for our definition of air pollution compared to that of water pollution. The changes mainly seek to encompass our increasing understanding of the complexity of pollution itself.
“Physical, chemical or biological processes”
As mentioned in the previous post, one issue of air pollution is the presence of secondary air pollutants. While primary air pollutants are introduced directly to indoor and outdoor environments, secondary air pollutants are formed as a result of processes and reaction with the environment (Nazaroff & Weschler, 2004). Thus, one consideration when formulating the definition for air pollution is the importance of pollutants that can affect us directly and indirectly, in their original or secondary form.
One of such pollutants that can affect us in a myriad of ways is Nitrogen Oxides (NOx). In its primary form, it can lead to discomfort or even problems with our respiratory system (Gauderman et al., 2005). In the presence of sunlight, it can transform into a secondary pollutant Ozone (O₃), a main component of smog and one of the culprits of persistent air pollution in the United States (Hill, 2010).
Source: Living in the environment: an introduction to environmental science. (Miller Jr, 1992)
A contaminant may be harmless at first but become harmful after undergoing accumulation via physical processes or transformation via chemical or biological processes (Obrist et al., 2017). One such example relates to the recent COVID-19 pandemic, where it has also shown how PM2.5 exposure interacts with the airborne disease to exacerbate mortality rates (Wu et al., 2020). Hence, we try to allow our definition to encompass the complexity of a pollutant’s life cycle into our definition itself.
“Quality of life”
After reflecting on our definition of water pollution, we realised the importance of the qualitative aspect of pollution. Hence, we try to cover all bases and include the impacts of air pollutants we generally overlook.
One important qualitative aspect of air pollution is its interaction with our senses. Foul smell or low visibility not only reflects the extent of harm of an air pollutant, it also affects our quality of life. For example, poor visibility, in extreme cases, can lead to the disruption of flights (Rusmana, 2019). This can cause problems such as stress that may not significantly impair human health, but certainly affect the quality of life of those affected.
Source: https://edition.cnn.com/travel/article/himalayas-visible-lockdown-india-scli-intl/index.html#:~:text=%22For%20the%20first%20time%20in,India’s%20lockdown%20clearing%20air%20pollution.&text=Delhi%20saw%20up%20to%20a,Central%20Pollution%20Control%20Board%20found
Conclusion
As mentioned, our definition of air pollution is “the introduction of contaminant(s) that, through physical, chemical or biological processes, cause(s) or result(s) in deterioration of human health and/or quality of life”. In today’s post, we have gone through our thought process behind some of the improvements in our definition. Hopefully, this has helped to clarify and understand why we do so! With this new understanding in mind, let us look at how the Singapore government defines air pollution under their laws!
See you there!
Ryan
References
Gauderman, W. J., Avol, E., Lurmann, F., Kuenzli, N., Gilliland, F., Peters, J., & McConnell, R. (2005). Childhood asthma and exposure to traffic and nitrogen dioxide. Epidemiology, 737-743.
Hill, M. K. (2010). Understanding Environmental Pollution: Cambridge University Press.
Miller Jr, G. T. (1992). Living in the environment: an introduction to environmental science: Wadsworth Publishing Company, Inc.
Nazaroff, W. W., & Weschler, C. J. (2004). Cleaning products and air fresheners: exposure to primary and secondary air pollutants. Atmospheric environment, 38(18), 2841-2865.
Obrist, D., Agnan, Y., Jiskra, M., Olson, C. L., Colegrove, D. P., Hueber, J., . . . Helmig, D. (2017). Tundra uptake of atmospheric elemental mercury drives Arctic mercury pollution. Nature, 547(7662), 201-204.
Rusmana, Y. (2019). Air Quality in Singapore, Kuala Lumpur and Jakarta Worst in the World. Bloomberg. Retrieved from https://www.bloomberg.com/news/articles/2019-09-18/singapore-s-air-worsens-to-unhealthy-levels-asia-haze-update
Wu, X., Nethery, R. C., Sabath, B. M., Braun, D., & Dominici, F. (2020). Exposure to air pollution and COVID-19 mortality in the United States. medRxiv.