Air Pollution and Polluting Particles: Comparison
View Latest Version
Please note this is a comparison between Version 2 by Rita Xu and Version 1 by Carmen Adella Sirbu.

Air pollution is a real public health problem, it being one of the five most common causes of mortality in developing countries. Pollution is universally widespread, already a matter of public interest, so that, although intuitive, it is difficult to connect the two. The particles found in the air that we breathe, regardless of their origin, can attack the body in different ways, causing inflammation, and triggering a true cascade of phenomena that end up attacking the central nervous system and other organs.

Air pollution is a real public health problem, it being one of the five most common causes of mortality in developing countries. Pollution is universally widespread, already a matter of public interest, so that, although intuitive, it is difficult to connect the two. The particles found in the air that researchers breathe, regardless of their origin, can attack the body in different ways, causing inflammation, and triggering a true cascade of phenomena that end up attacking the central nervous system and other organs.

  • stroke
  • air pollution
  • neuroinflammation

1. Introduction

Air pollution (AP) is a real public health problem, it being one of the five most common causes of mortality in developing countries [1]. Although the intuitive link between pollution and diseases such as myocardial infarction, diabetes, or other lung pathologies was established, a potential connection between pollution and central nervous system diseases has had increased interest in recent years (Table 1) [2].
Given that stroke is globally the second leading cause of death and the leading cause of disability [3], the identification of all risk factors, including the possibility of prevention and treatment, has become a matter of wide interest, with special importance for public health [4,5][4][5].
The usual risk factors involved in ischemic events are numerous, including smoking, an unbalanced diet, excessive alcohol, hypertension, a sedentary lifestyle, and dyslipidemia [6,7][6][7]. Beyond all other known risk factors, AP appears to be the third leading cause of stroke in the world, and it is a changeable contributing factor independent of human behavior [8,9][8][9]. The World Health Organization (WHO) estimates that AP is responsible for approximately 4.2 million premature deaths annually, accounting for up to 30% of stroke causes in developing countries, and it had more victims in previous years than COVID-19 did [10,11,12][10][11][12]. Moreover, recent studies estimate that, in the event of delays in pollution reduction measures, the number of deaths could double in the next 30 years [13]. During the current pandemic, the initial periods of global lockdown unexpectedly led to a decrease in pollution levels. At the same time, there was a dramatic decrease in the incidence of stroke during the initial period of the COVID-19 pandemic, even though people had a more sedentary lifestyle and an inadequate diet during this period. This may have been due, on the one hand, to reduced addressability in the hospital due to the restrictions imposed by the epidemiological situation and, on the other hand, the decrease in the level of pollution may have resulted in a decrease in the number of vascular events [3,14][3][14]. For a long time, the link between pollution and stroke was not universally accepted. First, many studies included both ischemic and hemorrhagic events as “strokes”, without an exact delimitation between the two entities, which have different risk factors. Second, the measurements did not have the necessary accuracy, which could have led to errors. In addition, the pathogenic mechanisms are incompletely known [3].

2. Air Pollution and Polluting Particles

AP is a comprehensive term that refers to thousands of harmful particles found in the air of various sources that affect the state of health, and can be found in liquid, solid, or gaseous form, often as mixtures in varying percentages [15]. Particulate matter (PM) represents a mix of extremely heterogeneous substances, regardless of the shape, size, and chemical composition. Increased attention is paid to particles with a diameter of less than 10 µm, because, due to their small size, they can be easily inhaled, later reaching the alveolar level and from there the whole body [16]. The typical classification and recognition of PM are performed according to their size, as follows [15,17,18][15][17][18]. PM10 (particles with a maximal diameter of 10 µm), whose source is represented by the soil industry, mining, or dust produced by vehicles or after construction; and PM2.5 (particles with a maximal diameter of 2.5 µm), resulting from the use of fuels, from the burning of oils or wood, composed of nitrates, sulfates, or complex organic molecules. In addition, substances resulting from the combustion of diesel vehicles participate in the production of PM2.5. A subcategory is represented by PM0.1 (particles with a maximal diameter of 0.1 µm). Particles emitted by burning fossil fuels are a major source of pollution. SO2 is also obtained by burning fossil fuels. Instead, gaseous components come from burning fossil fuels, heavy traffic, and extreme temperatures in some industries [15,19][15][19]. Carbon-based fuels used in oxygen-poor atmospheres or at extreme temperatures are CO generators. Taking the above into account, it is easy to deduce that the composition of the air differs in various regions of the globe, taking into account urban or rural areas, the degree of development of various areas, and especially local customs. In developed countries, transport is the main source of pollution, emitting huge levels of PM, along with activities necessary for daily living and the agricultural industry. For example, data released by the UK government estimate that the industry is responsible for producing about half of NO2 and 36% of PM10 emissions, while transport produces about 30% of NO2 and 18% of PM10. In extreme low-income countries, the use of biomass and solids is the main source of pollution, especially in homes. Burning coal or unprocessed wood is a significant source of pollution, given that countries such as South Africa or a significant part of South Asia use these resources to heat or cook in the traditional way [20]. For example, in India, the main sources of air pollution are biomass or coal combustion, used as heat or energy generators, windblown dust, agriculture, the construction industry, and, to a lesser extent, transportation and diesel combustion. Instead, in indoor environments, the burning of fossil fuels such as wood, coal, or residues obtained from daily activities is a major source of pollution. A recent study in India not only strengthens the existing evidence of PA damage, but also demonstrated the improved air parameters during the lockdown imposed by the COVID-19 pandemic. Instead, with the adoption of relaxation measures, pollution levels returned to an upward slope, demonstrating the link between PM production and daily human activity [21]. Pollution varies not only spatially but also temporally and is strongly influenced by various environmental conditions, even depending on the time of day or season. For example, the presence of wind, speed, or direction influences the concentration of PM, temperature contributes intensely to the formation of ozone, so pollution reaches a significantly higher level during the hours of the day with strong sunlight [15,22,23][15][22][23]. On the other hand, recent studies in Ireland suggested a strong association between PM2.5 pollution and the high rate of stroke events in the winter months [24,25][24][25]. Given the recent increased interest in pollution levels, many countries are trying to meet the recommended quality standards. Recent studies in the UK show that, in recent decades, PA has declined significantly in many high-income countries, but has tended to stagnate in recent years. On the other hand, in middle- and low-income countries, the situation is constantly deteriorating, and the levels of polluting particles are constantly rising in the USA, and countries in Africa and Asia [20]. Thus, taking into account PM2.5 exposure (µg/m3), the most polluted country in the world is Bangladesh (77.1 µg/m3), followed by Pakistan (59.0 µg/m3) and India (51.9 µg/m3). The least polluted countries are Puerto Rico, New Caledonia, and the US Virgin Islands (3.7 µg/m3) [26]. Romania has a PM2.5 exposure of 15.8 µg/m3 [27].
Table 1. Main gaseous pollutants and their effects on different systems or organs.
References Polluting Substance Source of Production Effect on the CNS Other Systemic Effects
W.S. Tunnicliffe et al. (2000) [28]; Nan Sang et al. (2010) [29]; Kuan Ken Lee et al. (2018) [15] SO2 Released from fossil fuel power plants Inhaling SO2 could aggravate existing ischemic brain damage It promotes vasoconstriction in both healthy adults and those with pre-existing asthma
M.A. Go’mez-Garcıa (2004) [30]; Radim J. Sram et al. (2017) [31]; Denise Felber Dietrich et al. (2008) [32]. NOx

NO2		 Motorized traffic, destruction by incineration of waste, and burning of coal or oil NO2 is associated with dementia.

Nox is associated with Parkinson’s disease.		 NO2 exposure is associated with autonomic cardiac dysfunction, especially in women and patients with underlying cardiovascular diseases.
Richard J. Levy (2014) [33]; Cyril Reboul et al. (2017) [34]. CO Vehicle exhausts, industrial combustion, cigarette smoke, gas cookers, charcoal grills. Exposure to low levels causes episodes of headache, dizziness, and impaired judgment. Exposure to high levels can cause seizures. It aggravates myocardial contractile dysfunction, especially in prone patients;

CO can cross the placenta, with the possibility of the neurodevelopmental alteration of the fetus
Helen H. Suh et al. (2000) [35]; Liu X. et al. (2022) [36] O3 (Ozone) O3 is formed through the interaction between NO2 and volatile organic compounds, under the action of sunlight Memory impairment, lethargy, severe fatigue, headache episodes, sleep-wake disturbance Irritating respiratory membranes and the entire respiratory system.

Increases the frequency of asthma attacks, weak the immune system, decrease metabolic function

Legend: CNS = central nervous system; SO2 = sulfur dioxide; NOx = nitrogen oxides; NO = nitrous oxide; CO = carbon monoxide; O3 = ozone.

References

  1. Graber, M.; Mohr, S.; Baptiste, L.; Duloquin, G.; Blanc-Labarre, C.; Mariet, A.; Giroud, M.; Bejot, Y. Air pollution and stroke. A new modifiable risk factor is in the air. Rev. Neurol. 2019, 175, 619–624.
  2. Butland, B.; Atkinson, R.; Crichton, S.; Barratt, B.; Beevers, S.; Spiridou, A.; Hoang, U.; Kelly, F.J.; Wolfe, C.D. Air pollution and the incidence of ischaemic and haemorrhagic stroke in the South London Stroke Register: A case—Cross-over analysis. J. Epidemiol. Community Health 2017, 71, 707–712.
  3. Verhoeven, J.I.; Allach, Y.; Vaartjes, I.C.H.; Klijn, C.J.M.; de Leeuw, F.E. Ambient air pollution and the risk of ischaemic and haemorrhagic stroke. Lancet Planet Health 2021, 5, e542–e552.
  4. Niu, Z.; Liu, F.; Yu, H.; Wu, S.; Xiang, H. Association between exposure to ambient air pollution and hospital admission, incidence, and mortality of stroke: An updated systematic review and meta-analysis of more than 23 million participants. Environ. Health Prev. Med. 2021, 26, 15.
  5. Hickel, J. Quantifying national responsibility for climate breakdown: An equality-based attribution approach for carbon dioxide emissions over the planetary boundary. Lancet Planet Health 2020, 4, e399–e404.
  6. Qi, X.; Wang, Z.; Guo, X.; Xia, X.; Xue, J.; Jiang, G.; Gu, Y.; Han, S.; Yao, Q.; Cai, Z.; et al. Short-term effects of outdoor air pollution on acute ischaemic stroke occurrence: A case-crossover study in Tianjin, China. Occup. Environ. Med. 2020, 77, 862–867.
  7. Tian, Y.; Liu, H.; Zhao, Z.; Xiang, X.; Li, M.; Juan, J.; Song, J.; Cao, Y.; Wang, X.; Chen, L.; et al. Association between ambient air pollution and daily hospital admissions for ischemic stroke: A nationwide time-series analysis. PLoS Med. 2018, 15, e1002668.
  8. Zhang, R.; Liu, G.; Jiang, Y.; Li, G.; Pan, Y.; Wang, Y.; Wei, Z.; Wang, J.; Wang, Y. Acute effects of particulate air pollution on ischemic stroke and hemorrhagic stroke mortality. Front. Neurol. 2018, 9, e1002668.
  9. Oudin, A.; Forsberg, B.; Jakobsson, K. Air pollution and stroke. Epidemiology 2012, 23, 505–506.
  10. Farge, E. Pollution Causing More Deaths than COVID, Action Needed, Says UN Expert. 2022. Available online: https://www.reuters.com/business/environment/pollution-causing-more-deaths-than-covid-action-needed-says-un-expert-2022-02-15/ (accessed on 23 March 2022).
  11. Cowen, T. Air Pollution Kills Far More People than Covid Ever Will. 2021. Available online: https://www.bloomberg.com/opinion/articles/2021-03-10/air-pollution-kills-far-more-people-than-covid-ever-will (accessed on 23 March 2022).
  12. Air Pollution. Available online: https://www.who.int/health-topics/air-pollution#tab=tab_1 (accessed on 23 March 2022).
  13. Jeremy, W. Air pollution and brain health: An emerging issue. Lancet Neurol. 2018, 17, 103.
  14. Avellaneda-Gómez, C.; Vivanco-Hidalgo, R.; Olmos, S.; Lazcano, U.; Valentin, A.; Milà, C.; Ambrós, A.; Roquer, J.; Tonne, C. Air pollution and surrounding greenness in relation to ischemic stroke: A population-based cohort study. Environ Int. 2022, 161, 107147.
  15. Lee, K.K.; Miller, M.R.; Shah, A.S. Air pollution and stroke. J. Stroke 2018, 23, 505–506.
  16. Franchini, M.; Mannucci, P.M. Thrombogenicity and cardiovascular effects of ambient air pollution. Blood 2011, 118, 2405–2412.
  17. Genc, S.; Zadeoglulari, Z.; Fuss, S.H.; Genc, K. The adverse effects of air pollution on the nervous system. J. Toxicol. 2012, 2012, 1–23.
  18. Talbott, E.O.; Rager, J.R.; Benson, S.; Brink, L.A.; Bilonick, R.A.; Wu, C. A case-crossover analysis of the impact of PM2.5 on cardiovascular disease hospitalizations for selected CDC tracking states. Environ. Res. 2014, 134, 455–465.
  19. Rhinehart, Z.J.; Kinnee, E.; Essien, U.R.; Saul, M.; Guhl, E.; Clougherty, J.E.; Magnani, J.W. Association of fine particulate matter and risk of stroke in patients with atrial fibrillation. JAMA Netw. Open 2020, 3, e2011760.
  20. Maheswaran, R. Air pollution and stroke—An overview of the evidence base. Spat. Spatio-temporal Epidemiol. 2016, 18, 74–81.
  21. Pandey, A.; Brauer, M.; Cropper, M.L.; Balakrishnan, K.; Mathur, P.; Dey, S.; Turkgulu, B.; Kumar, G.A.; Khare, M.; Beig, G.; et al. Health and economic impact of air pollution in the states of India: The Global Burden of Disease Study 2019. Lancet Planet Health 2021, 5, e25–e38.
  22. Chen, R.; Yin, P.; Meng, X.; Liu, C.; Wang, L.; Xu, X.; Ross, J.A.; Tse, L.A.; Zhao, Z.; Kan, H.; et al. Fine particulate air pollution and daily mortality: A nationwide analysis in 272 Chinese cities Renjie. Am. J. Respir. Crit. Care Med. 2017, 196, 73–81.
  23. Suwa, T.; Hogg, J.C.; Quinlan, K.B.; Ohgami, A.; Vincent, R.; van Eeden, S.F. Particulate air pollution induces progression of atherosclerosis. J. Am. Coll. Cardiol. 2002, 39, 935–942.
  24. Byrne, C.P.; Bennett, K.E.; Hickey, A.; Kavanagh, P.; Broderick, B.; O’Mahony, M.; Williams, D.J. Short-term air pollution as a risk for stroke admission: A time-series analysis. Cerebrovasc. Dis. 2020, 49, 404–411.
  25. Guo, Y.; Xie, X.; Lei, L.; Zhou, H.; Deng, S.; Xu, Y.; Liu, Z.; Bao, J.; Peng, J.; Huang, C. Short-term associations between ambient air pollution and stroke hospitalisations: Time-series study in Shenzhen, China. BMJ Open 2020, 10, e032974.
  26. Fosdike, H. The World’s Most and Least Polluted Countries. Available online: https://www.u-earth.eu/post/world-most-least-polluted-countries (accessed on 23 March 2022).
  27. World’s Most Polluted Countries & Regions (Historical Data 2018–2021). Available online: https://www.iqair.com/world-most-polluted-countries (accessed on 23 March 2022).
  28. Tunnicliffe, W.; Hilton, M.; Harrison, R.; Ayres, J. The effect of sulphur dioxide exposure on indices of heart rate variability in normal and asthmatic adults. Eur. Respir. J. 2001, 17, 604–608.
  29. Sang, N.; Yun, Y.; Li, H.; Hou, L.; Han, M.; Li, G. SO2 Inhalation contributes to the development and progression of ischemic stroke in the brain. Toxicol. Sci. 2010, 114, 226–236.
  30. Gómez-García, M.A.; Pitchon, V.; Kiennemann, A. Pollution by nitrogen oxides: An approach to NOx abatement by using sorbing catalytic materials. Environ. Int. 2005, 31, 445–467.
  31. Sram, R.J.; Veleminsky, M.; Veleminsky, M.; Stejskalová, J. The impact of air pollution to central nervous system in children and adults. Neuroendocrinol. Lett. 2017, 38, 389–396.
  32. Felber Dietrich, D.; Gemperli, A.; Gaspoz, J.M.; Schindler, C.; Liu, L.J.S.; Gold, D.R.; Schwartz, J.; Rochat, T.; Barthélémy, J.D.; Pons, M.; et al. Differences in heart rate variability associated with long-term exposure to NO2. Environ. Health Perspect. 2008, 116, 1357–1361.
  33. Levy, R.J. Carbon monoxide pollution and neurodevelopment: A public health concern. Neurotoxicol. Teratol. 2015, 49, 31–40.
  34. Reboul, C.; Boissière, J.; André, L.; Meyer, G.; Bideaux, P.; Fouret, G.; Feillet-Coudray, C.; Obert, P.; Lacampagne, A.; Thireau, J.; et al. Carbon monoxide pollution aggravates ischemic heart failure through oxidative stress pathway. Sci. Rep. 2017, 7, 39715.
  35. Suh, H.H.; Bahadori, T.; Vallarino, J.; Spengler, J.D. Criteria air pollutants and toxic air-pollutants. Environ. Health Perspect. 2000, 108 (Suppl. S4), 625–633.
  36. Liu, X.; Li, Z.; Zhang, J.; Guo, M.; Lu, F.; Xu, X.; Deginet, A.; Liu, M.; Dong, Z.; Hu, Y.; et al. The association between ozone and ischemic stroke morbidity among patients with type 2 diabetes in Beijing, China. Sci. Total Environ. 2022, 818, 151733.
More
© Text is available under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)
Video Production Service
Feedback