You’re Smoking Everyday and You Don’t Even Know It!

Studies have shown that smoking cigarettes is associated with an increased risk of heart and lung conditions as well death. To be precise, smoking as little as 1 to 4 cigarettes daily has been associated with an increased risk of dying from heart disease or lung cancer (Bjartveit et al.,2005). Yet what if we told you that the air you breathe is equivalent to smoking 4 cigarettes daily, would you be worried about how this impacts on your health?

In the Muller and Muller study published by Berkeley Earth, two researchers sought to make air pollution relatable to the average person. Hence, using data from the USA and China, an estimation was generated.

At that time, it was estimated that in the US, there were 1.37 deaths per million cigarettes smoked. In China it was estimated that 1.6 million people died every year from an exposure of 52 µg/m3 of PM_2.5. Using these two calculations it meant that 1.1 trillion cigarettes would be required to kill 1.6 million people. Taking the population of China as 1.35 billion people at that time, 864 cigarettes per person per annum or 2.4 cigarettes per person per day was attributed to death. Going back to the average exposure of a person in China as 52 µg/m3 of PM_2.5 meant that this was equivalent to the exposure of 2.4 cigarettes. Hence one cigarette is equivalent to 21.67 µg/m3 of PM_2.5. In most reports this number has been rounded up to 22 µg/m3 of PM_2.5.

This has inspired us to make our own cigarette calculator and you try it here:

Let us know how many cigarettes you already smoked in your lifetime!

References:

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[2] Gallucci G, Tartarone A, Lerose R, Lalinga AV, Capobianco AM. Cardiovascular risk of smoking and benefits of smoking cessation. J Thorac Dis. 2020 Jul;12(7):3866-3876. doi: 10.21037/jtd.2020.02.47. PMID: 32802468; PMCID: PMC7399440.

[3] Hackshaw A, Morris JK, Boniface S, Tang JL, Milenković D. Low cigarette consumption and risk of coronary heart disease and stroke: meta-analysis of 141 cohort studies in 55 study reports. BMJ. 2018 Jan 24;360:j5855. doi: 10.1136/bmj.j5855. Erratum in: BMJ. 2018 Apr 11;361:k1611. doi: 10.1136/bmj.k1611. Erratum in: BMJ. 2018 Nov 28;363:k5035. doi: 10.1136/bmj.k5035. PMID: 29367388; PMCID: PMC5781309.

[4] Jiang C, Chen Q, Xie M. Smoking increases the risk of infectious diseases: A narrative review. Tob Induc Dis. 2020 Jul 14;18:60. doi: 10.18332/tid/123845. PMID: 32765200; PMCID: PMC7398598.

[5] Muller, R.A. & Muller, E.A., 2015. Air Pollution and Cigarette Equivalence. Berkeley Earth. Available at: https://berkeleyearth.org/air-pollution-and-cigarette-equivalence/ [Accessed 27 June 2025].

[6] Schane RE, Ling PM, Glantz SA. Health effects of light and intermittent smoking: a review. Circulation. 2010 Apr 6;121(13):1518-22. doi: 10.1161/CIRCULATIONAHA.109.904235. PMID: 20368531; PMCID: PMC2865193.

[7] Zhu D, Zhao G, Wang X. Association of Smoking and Smoking Cessation With Overall and Cause-Specific Mortality. Am J Prev Med. 2021 Apr;60(4):504-512. doi: 10.1016/j.amepre.2020.11.003. PMID: 33745522.