Potential Hazards of Air Pollution on Environment, Health and Agriculture
Sushan Chowhan*
Bangladesh Institute of Nuclear Agriculture, Bangladesh
Submission: April 19, 2021; Published: May 25, 2021
*Corresponding author: Sushan Chowhan, BINA Sub-station, RARS campus (behind ATI, Aronkhola), Ishurdi, Pabna-6620, Bangladesh
How to cite this article: Sushan C. Potential Hazards of Air Pollution on Environment, Health and Agriculture. Int J Environ Sci Nat Res. 2021; 28(2): 556231. DOI: 10.19080/IJESNR.2021.28.556231
Abstract
Air is an essential element of the earth’s atmosphere. Modern civilization and industrialization have rapidly changed the world and also uplifted the rate of different environmental pollutions. The serious consequences of air pollution cannot be ignored as it is related to maintain all sorts of life on earth. This article reviews the possible threat of air pollution on environment, health and crop production. During 2020, out of top 50 air polluted cities around the globe, 49 were from Bangladesh, China, India, and Pakistan. Intensity of PM2.5 and PM10 at various region of Bangladesh were 56.22-210.45μg/m3 and 163.41-316.31μg/m3 respectively. PM2.5 was superiorly (58%) responsible for air pollution in Dhaka city. Level of different air pollutants (PM, NOx, SO2, CO, O3) relied on activity, time and seasonal variation. COVID-19 pandemic significantly decreased PM emissions nearly 28% in Malaysia, 75% in Morocco and around 21% in China. Numerous serious health risk of air pollution was observed; among them death from cardio vascular (32.77%), cancers (10.49%) and respiratory diseases (10.21%) was main. SO2, NOx, fluorides and O3 were noted to be the key pollutants to hamper crop adaptation to stress and also reduce the production. Yield reduction of rice (about 15%), corn (nearly 20%) and wheat (almost 40%) was significant in an increased concentration of O3. Some prime remedy to control and minimize air pollutions were remarked as- improvement of public transportation system, shifting industries and brick kilns away from urban areas, setting and using waste treatment plant in industries, using ecofriendly green technologies, raising public awareness on air pollution through mass and social medias, enforcing environment pollution law by the government. Air pollution control and reduction requires a combination of many approaches; it is high time to take necessary action to stop and prevent air pollution now else our future generation will suffer endlessly.
Keywords: Air pollution; AQI; PM2.5; PM10; SOx; NOx; O3; Air pollution induced crop yield; Bangladesh
Introduction
Air is the inseparable physical part of earth’s atmosphere and so much important to maintain life and ecosystem. Major composition of air is nitrogen (78%) and oxygen (21%); rest are minor gases (mostly argon; along with trace amounts of carbon dioxide, methane, hydrogen, helium etc.) which comprises approximately 1% of the total air [1]. Constitution of air is balanced in such a way that is favorable for all living beings of the planet and the atmospheric chemistry is vastly reliant on the living organisms in the biosphere [2]. Unlike other planets in the solar system life is impossible mainly due to air composition and temperature. Constituents of air largely depends on temperature i.e., air temperature which is directly related with warming or cooling of a location. Increase or decrease of earth’s temperature is natural process but, human emissions of various gases play a significant role [3]. More the gas molecules move more quickly the air temperature increases and vice versa. Any serious alteration in the air configuration accelerates changes in environment and its elements. Environmental pollution is any discharge of material or energy into water, land, or air that causes or may cause acute (short-term) or chronic (long-term) detriment to the earth's ecological balance or that lowers the quality of life [4]. Long term or stable state of modified air composition causes air pollution, which also contributes to global warming. The organization of earth’s atmosphere altered remarkedly over time by human activities [5]. Fluctuations in environment are hurtful to human health, crops and ecosystems. While humans are the vital part of an ecosystem, the urban ecosystem is hostilely affected by several air pollutants like- particulate matter (PM) and hazardous air pollutants (HAPs) [6,7]. More than one-third of Bangladesh’s population live in large urban areas. By 2050, at least half of the population will be urbanized [8]. The highest concentration of population growth has been in and around Dhaka (latitude 23.77°N, longitude 90.38°E), the capital of Bangladesh; which is one of the most densely populated cities in the world (ranked within the top 15), with a population density of approximately 28,000 per sq. km as per 2016 [9]. There has been an eightfold increase in population since 1970, and it now stands almost 22 million, making it the seventh largest city in the world [10]. Key air pollutants may be present in gaseous forms, particles in suspension, various ionizing radiation. Gaseous forms are mostly oxidized and reduced of carbon (CO2, CO, CH4), nitrogen (NO2, NO, N2O4, NH3, NH4+), SO2, O3, C6H6 vapors, Hg, volatile phenols, Cl2, etc. Particulate forms are- PM10 (particles diameter ≤ 10mm) and PM2.5 (particles diameter ≤ 2.5mm) particulate matter, heavy metals (Pb, Ni, Cd, As) with toxic effect, polycyclic aromatic hydrocarbons (PAH) etc. [4]. In South Asia, airborne particulate matter (PM10 and PM2.5) is a major concern because of its high ambient concentrations and documented impact on morbidity and premature mortality [11]. Air pollution presently a major environmental concern in all large cities of the world including Dhaka city of Bangladesh [12]. In this mega city air pollution is widely occurred by emissions from road traffic [13], brick kilns, dust from roads, construction sites and toxic fumes from industries [14]. For instance, South East France as well as Dhaka city is one of the region’s most influenced by atmospheric pollution [15]. However, particulate matter (PM) pollution is basically believed to be a major indicator of urban air quality and is linked to human health hazards [16]. On the other hand, air pollutants negatively affect crop production, yield and thereby involved ecosystems of beneficial insects, vertebrates etc. [17,18].
Impact of air pollution is vast, complex and quite hard to quantify. Nearly it’s impossible to stop or eradicate air pollution fully from the environment. With the pace of time human civilization has become modernized and machine dependent resulting enhanced pollution than earlier times. Thus, it’s imperative to know about the air pollution to keep our environment clean and pollution free. Considering these situation, a thorough review was done to briefly expose the main causes, areas, effects and remedies to control air pollution so that we can lead a healthy and sound life.
Discussion
Causes and scenario of air pollution
Air pollution is an emerging problem in many countries. Yet, attention to date has been on its impact on human health, environment and finally on food production. Out of 50 cities, 49 are from Bangladesh, China, India, and Pakistan which are most polluted. Currently Bangladesh is the top air polluted country (77.1μg/m³) where 80% of it’s cities are ‘unhealthy’ (> 55.5μg/m³) as per US AQI (United States Air Quality Index) measurement. In terms of PM2.5 pollution, Dhaka holds the second position globally [19]. Cause of upsurge in pollution level in Dhaka is due to unplanned urbanization, industrialization, and motorization. Brick kiln operations in and around Dhaka are also liable for a large share of Dhaka’s polluted air, which accounts for 58% of total fine particulate matter PM2.5 pollution, followed by motor vehicles (10.4%), road dust (7.70%), fugitive Pb (7.63%), soil dust (7.57%), biomass burning (7.37%), and sea salt (1.33%) [20]. DoE [12] observed, concentration level of PM2.5 and PM10 at different locations of Bangladesh were 56.22-210.45μg/m3 and 163.41-316.31μg/m3 respectively; AQI impression was unhealthy to extremely unhealthy along with few good, moderate and caution; most frequent responsible pollutant was PM2.5. Emission rate of PM2.5 from different types of vehicles was much higher which used diesel and lowest with CNG (Compressed Natural Gas) (Table 1).
Concentration of different air pollutant i.e., PM, NOx, SO2, CO, O3 depends on human activities, time and seasonal variations. PM and NOx are reduced during weekends and national holidays. It was noticed that a declining trend of PMs occurred between time 13.00 to 17.00hrs., lowest SO2 concentration between 13.00 to 15.00hrs., minimum level of NO, NO2, NOx at 12.00 to 17.00hrs whereas O3 intensity was lower from 1.00hrs to 10.00hrs then it had a up lining trend. Less CO was observed among 17.00 to 19.00hrs. later it rose (Figure 1). Reduced movement during COVID-19 pandemic significantly decreased PM emissions by almost 28% in Malaysia [23], 75% in Morocco [24], and about 21% in China [25]. Battery industries of old Dhaka city contributing to the degraded air quality by recycling heavy metals (Pb, Hg etc.) in the open places [26].
Major air pollution (Table 2) is produced from industry, agriculture, transports and urbanization. Hydrocarbon burning in motor engines escalates CO2, CO, SO2, NOx, NO2 and C2H4 in various fractions. Industrial plants of chemical works, metal smelting release SO2, H2S, NO2, and HF (hydrogen fluoride) in the air. Though tall chimney stacks discharge these gases to a high altitude to prevent local pollution, but these pollutants return to earth. Sometimes photochemical smog is produced by complex reaction of sunlight, NOx (from urban and industrial origin) and volatile organic compounds from either vegetation (biogenic hydrocarbons) or human activities (anthropogenic hydrocarbons). Ozone (O3) and peroxyacetylnitrate (PAN). This smog can be deleterious to all living beings subjected to concentration and duration of exposure. Hydrogen peroxide (H2O2), is another potentially harmful molecule, generated through reaction of O3 and naturally released volatiles (terpenes) from forest trees. Nevertheless, intensity of detrimental gases is highly variable and depends on location, wind direction, rainfall, and sunlight. Pollutants emitted into the open air can react with constituents of the atmosphere and convert into more or less noxious compounds. Transformation of pollutants can also have indirect adverse effects on ecosystem biocoenosis, plants, animals and human health (Figure 1) [4].
Health impacts
A wide range of air pollutants are primely responsible for occurring various fatal in disease in humans. Amongst them, PMs, enter the respiratory system through inhalation causing respiratory and cardiovascular disorders, reproductive problems, neuron dysfunctions and cancer. Despite the fact that O3 in the stratosphere defend us against ultraviolet irradiation but, it’s high concentration at ground is unsafe as it affects the respiratory and cardiovascular system. Furthermore, nitrogen oxide (NOx), sulfur oxide (SOx), Volatile Organic Compounds (VOCs), dioxins, and polycyclic aromatic hydrocarbons (PAHs) are all considered air pollutants that are dangerous to humans. Breathing Carbon monoxide (CO) in high levels can be poisonous. Absorption of lead (Pb) like heavy metals in body can result direct poisoning or chronic intoxication depending on exposure. Diseases occurring from the aforementioned substances include predominantly respiratory difficulties such as Chronic Obstructive Pulmonary Disease (COPD), asthma, bronchiolitis, and also lung cancer, cardiovascular events, central nervous system dysfunctions, and cutaneous diseases. Environmental pollution ensuring climate change affects the global dispersal of several infectious diseases [29]. Air pollution is highly considered to be associated with the above-mentioned health complexities [30].
Earlier findings (Table 3) denotes that, higher level of exposure and concentration of Nitrogen oxide (NOx), Sulphur Dioxide (SOx), Carbon Monoxide (CO), Carbon dioxide (CO2), Volatile Organic Carbon (VOC), Oxygen (O2), Ozone (O3), Lead (Pb), Particulate Matter (PM), Suspended Particulate Matter (SPM), Relative Humidity (RH), Hydrogen Sulfide (H2S) negatively effects human body and organs [28,31]. Extreme air pollution is attributed to cardiovascular disease (CVD), asthma, stroke, COPD, acute lower respiratory infections in children, and lung cancer [32]. Maximum mortality in Bangladesh is occurred by cardiovascular disease, followed by cancers, respiratory disease, and diabetes (Figure 3). Research findings indicate that increased death from CVD and respiratory diseases in Bangladesh were mainly due to more exposure to fine particulate matter mass [33]. Rest causes were found to be excessive smoking, changes food habit, lifestyle and physical fitness [34]. High blood pressure,smoking and outdoor air pollution ranked first, second and third risk factors respectively for mortality in Bangladesh [35,36]. In 2015, over 120,000 people died because of peak exposure to PM2.5 [37]. Thus, an increasing trend in death level was noticed from the year 2000 to 2015 (Figure 4).
Consequences on crop production
Apart from destruction of human health air pollutants are also damaging the yield of food crops, their nutritional quality and safety, imposing a major risk to food security. As per report of 2014, air pollution has decreased the yields of wheat and rice by half in India. Researchers mostly ascribe this to ground level O3. Notably between 1980 and 2010 yields were up to 36% lower than what would have been without air pollution trends [38].
Latest research investigations indicate that, crop production is seriously hampered by a number of air pollutants (sulphur dioxide (SO2), Nitrogen oxides (NOx), and Ozone (O3). These pollutants create reactive oxygen species (ROS), which negatively affect biochemical activities of plants and decrease their adaptive capacity stresses. Some imperative physiological processes like- photosynthetic CO2 fixation and energy metabolism are also affected by the pollutants. Impact of air pollutants depends not only upon its concentration, but also on the duration and composition of air pollutants. Ozone is the most phytotoxic element among the available air pollutants [39]. A list of common air pollutants and their influence and morphological symptoms on plant are described in Table 4.
Atmospheric particulate matter (PM) can enhance crop production through the redistribution of light from sunlight to shaded leaves. Nitrogen transported through the atmosphere can also increase crop production when deposited onto cropland by reducing nutrient limitations in these areas [41].
Air pollution induced climate change can trigger some crop’s production and can halt particulars yield. HYV aus, aman, boro and wheat production was found to be highest at 660ppmv CO2+000C. Wheat biomass and grain yield was maximum noted with 550ppm CO2 concentration. Most of C4 crops will be benefited by increased CO2 intensity in terms of yield and biomass production as they bear kranz anatomy in the vascular tissues and have better efficacy to utilize the extra CO2 during photosynthesis [43]. Yield loss of rice (about 15%), corn (about 20%) and wheat (about 40%) enhanced when amount of O3 concentration was increased (Figure 5).
Probable solutions to minimize air pollution
Complete eradication of air pollution is not possible but by taking and doing certain initiatives and works we can keep it within our tolerable limit. Some of the points to reduce air pollutants are stated below—
a) Improve public transportation in large cities and using the public transports instead of private.
b) Timely road maintenance.
c) Stopping deforestation; starting landscaping and gardening in the urban areas to promote afforestation/plantation inside the cities to maintain and restore the ecological balance to keep a green clean environment.
d) Improved cooking stoves in rural areas.
e) Air pollution mitigation plan and its enforcement in large construction projects.
f) Import control for quality of coal throughout the country, primarily brick and power industries.
g) Inspection, maintenance and technology specification of existing steel mills, cement and glass factories.
h) Maintaining the emissions standards at all new plants.
i) Utilizing the alternate construction material (such as ecofriendly bricks instead of soil burned bricks) over the country; especially large cites.
j) Strengthening vehicle inspection and maintenance especially large cities and completely banning old vehicles which are more than 20 years old.
k) Immediate relocation/shifting the industries (such as tanneries, battery, pharmaceutical, tobacco, brick kilns) away from the residential area and major cities.
l) Establishing and using waste treatment plant in the industries.
m) Using green technology.
n) Understanding the concept of reduce, reuse and recycle.
o) Emphasis on clean energy resources.
p) Practicing the habit of walking and riding bicycle.
q) Using hybrids vehicles and hydrogen fuel cells.
r) Switching off lights, fan, AC etc. when leaving the room.
s) Encouraging research works on environment pollution prevention.
t) Enforcement of existing law regarding environment pollution.
u) Creating public awareness on air pollution through mass media.
Conclusion
Air pollution is imposing an imminent threat globally in environment, health and crop production sectors. Due to upgradation of living standards, we are polluting the earth more over time. Pollutants like- CO, SOx, NOx, O3, Pb, PM2.5 and PM10 were mostly responsible for air pollution. These gaseous pollutants are produced from machine and engines. Health hazards like critical respiratory and pulmonary diseases are associated with these pollutants. Number of patients and deaths were also seen to increase over the years due to different air pollution related diseases. Agriculture production seemed to have both positive and negative effect on crop yields but that depends on the duration, concentration and exposure of the pollutants. Countries like Bangladesh contribute little to air pollution as it emits less amount of carbon in the atmosphere than USA, China etc. industrialized countries. But, in the last few decades massive rice production may have added methane (CH4) and ammonia (NH3) gases in the atmosphere thereby adding greenhouse gases (GHG). Since Bangladesh is an over populated country it’s of utmost and urgent importance to reduce air pollution by changing the way we live and think; so that we can keep our earth green and clean to breathe for our forthcoming generations.
Acknowledgement
The author praises utmost thanks and gratitude to N-27th Foundation Training Course for NARS scientist’s management authority, National Agriculture Training Academy (NATA), Gazipur, Bangladesh to organize the environment committee and provide scope to play role in the environmental issues and create awareness in NATA campus. Author is also indebted and expresses his sincere appreciation to environment committee members of this course for proposing such a time led topic to review as a part of the seminar presentation during the training course.
References
- Glueckauf E (1951) The Composition of Atmospheric Air. In: Malone TF (Ed.), Compendium of Meteorology. American Meteorological Society, Boston, MA, pp. 3-10.
- Felix JR, Anne LD (2006) Air pollution and very low birth weight infants: A target Population. Pediatrics 118(1): 156-164.
- Davidoff DK (2018) Chapter 3.4 The Greenhouse Effect, Aerosols, and Climate Change. In: Török B, Dransfield T (Eds.), Green Chemistry, Elsevier, pp. 211-234.
- Gheorghe IF, Ion B (2011) chapter 12 The Effects of Air Pollutants on Vegetation and the Role of Vegetation in Reducing Atmospheric Pollution. In: Khallaf M (Ed.), The Impact of Air Pollution on Health, Economy, Environment and Agricultural Sources, Intech, pp. 241-280.
- Arden CP, Richard TB, Micheal JT (2002) Lung cancer, cardiopulmonary mortality and long-term exposure to fine particulate air pollution. JAMA 287(9): 1132-1141.
- Ajayi AB, Dosunmu OO (2002) Environmental hazards of importing used vehicles into Nigeria. Proceedings of International Symposium on Environmental Pollution Control and Waste Management, pp. 521-532.
- Abam FI, Unachukwu GO (2009) Vehicular emission and air quality standards in Nigeria. European Journal of Scientific Research 34(4): 550-560.
- Begum BA, Hopke PK (2018) Ambient Air Quality in Dhaka Bangladesh over Two Decades: Impacts of Policy on Air Quality. Aerosol Air Qual Res 18(7): 1910-1920.
- Roy S, Sowgat T, Mondal J (2019) City Profile: Dhaka, Bangladesh. Environ Urban ASIA 10(2): 216-232.
- World Population Review (2021) World City Populations 2021.
- Kojima M, Brandon C, Shah J (2000) Improving urban air quality in south Asia by reducing emissions from two-stroke engine vehicles, The International Bank for Reconstruction and Development/The World Bank.
- DoE (Department of Environment) (2020) Monthly Air Quality Monitoring Report- Reporting Month: December 2020.
- Sicard P, Talbot C, Lesne O, Mangin A, Alexandre N, et al. (2012) The Aggregate Risk Index: An intuitive tool providing the health risks of air pollution to health care community and public. Atmospheric Environment 46: 11-16.
- Haque HA, Huda N, Tanu FZ, Sultana N, Hossain MSA, et al. (2017) Ambient air quality scenario in and around Dhaka city of Bangladesh. Barisal University Journal Part 1 4(1): 203-218.
- Plaia A, Ruggieri M (2011) Air quality indices: A Review. Rev Environ Sci Bio-technol 10: 165-179.
- Iqbal A, Afroze S, Rahman MM (2020) Vehicular PM Emissions and Urban Public Health Sustainability: A Probabilistic Analysis for Dhaka City. Sustainability 12(15): 6284.
- Agrawal M (2005) Effects of air pollution on agriculture : An issue of national concern. National Academy Science Letters 28(3): 93-106.
- Nigel J, Bell B, Marshall FM (2002) Effects of Air Pollution on Crops in Developing Countries. In: Ambasht RS, Ambasht NK (Eds.), Modern Trends in Applied Terrestrial Ecology. Springer, Boston, MA.
- IQAir (2020) World Air Quality Report-Region & City PM5 Ranking.
- Begum BA, Nasiruddin M, Randal S, Sivertsen B, Hopke PK (2014) Identification and apportionment of sources from air particulate matter at urban environments in Bangladesh. Br J Appl Sci Technol 4(27): 3930-3955.
- Iqbal A, Allan A, Zito R (2016) Meso-scale on-road vehicle emission inventory approach: A study on Dhaka City of Bangladesh supporting the cause-effect’ analysis of the transport system. Environ Monit Assess 188(3): 149.
- EEA (2009) EMEP/EEA Air Pollutant Emission Inventory Guidebook; European Environment Agency: Luxembourg, 2009.
- Abdullah S, Mansor AA, Napi NNLM, Mansor WNW, Ahmed AN, et al. (2020) Air quality status during 2020 Malaysia Movement Control Order (MCO) due to 2019 novel coronavirus (2019-nCoV) pandemic. Sci Total Environ 729: 139022.
- Otmani A, Benchrif A, Tahri M, Bounakhla M, Chakir EM, et al. (2020) Impact of Covid-19 lockdown on PM10, SO2 and NO2 concentrations in Salé City (Morocco). Sci Total Environ 735: 139541.
- Wang Y, Yuan Y, Wang Q, Liu C, Zhi Q, et al. (2020) Changes in air quality related to the control of coronavirus in China: Implications for traffic and industrial emissions. Sci Total Environ 731: 139133.
- Islam MM, Afrin S (2014) Air quality status of dhaka city and effects of seasons, weekends, eid and hartal days. 2nd International Conference on Advances in Civil Engineering (ICACE-2014). 26 –28 December, CUET, Chittagong, Bangladesh.
- Rahman MM, Mahamud S, Thurston GD (2019) Recent spatial gradients and time trends in Dhaka, Bangladesh, air pollution and their human health implications. Journal of the Air & Waste Management Association 69(4): 478-501.
- DoE (Department of Environment) (2012) Air Pollution Reduction Strategy for Bangladesh. pp. 16-74.
- Manisalidis I, Stavropoulou E, Stavropoulos A, Bezirtzoglou E (2020) Environmental and Health Impacts of Air Pollution: A Review. Front Public Health 8: 14.
- Sætterstrøm B, Kruse M, Hansen HB, Bønløkke JH, Flachs EM, et al. (2012) A Method to Assess the Potential Effects of Air Pollution Mitigation on Healthcare Costs. Journal of Environmental and Public Health 2012: 935825.
- Alam MZ, Armin E, Haque M, Halsey J, Kayesh E, et al. (2018) Air Pollutants and their Possible Health Effects at Different Locations in Dhaka City. Int J Environ Sci Nat Res 9(4): 555768.
- WHO (2014) 7 million premature deaths annually linked to air pollution.
- Hsu WH, Hwang SA, Kinney PL, Lin S (2017) Seasonal and temperature modifications of the association between fine particulate air pollution and cardiovascular hospitalization in New York State. Sci Total Environ 578: 626-632.
- Mamun MA, Rumana N, Pervin K, Azad MC, Shahana N, et al. (2015) Emerging burden of cardiovascular diseases in Bangladesh. J Atheroscler Thromb 23(4): 365-375.
- Roser HR (2018) Causes of death.
- IHME (2018) Global Burden of Disease Study 2016 (GBD 2016) data resources.
- Health Effects Institute (2017) State of Global Air 2017.
- The Sustainable Food Trust (2019) The impact of air pollution on crops.
- Devrajani SK, Qureshi M, Imran U, Nisa TUI (2020) Impact of Gaseous Air Pollutants on Agricultural Crops in Developing Countries: A review. Journal of Environmental Science and Public Health 4 (2020): 71-82.
- Eris G, Lyu C, Swartwood N (2016) Air Pollution Effects on Rice Yields in South Asia.
- Schiferl LD, Heald CL, Kelly D (2018) Resource and physiological constraints on global crop production enhancements from atmospheric particulate matter and nitrogen deposition. Biogeosciences 15: 4301-4315.
- Beig G (2013) Impact of air pollution on agriculture.
- Chowhan S, Ghosh S, Chowhan T, Hasan MM, Roni MS (2016) Climate change and crop production challenges: An overview. Research in Agriculture Livestock and Fisheries 3(2): 251-269.