Javed Iqbal1, Efftikhar Ahmad2, Rizwan Haider3, Helen Khokhar4, Fida-ur-Rehman5

1Govt. College University, Lahore (Pakistan) javediqbal.ji1956@gmail.com

2 National College of Business Administration and Economics, Lahore (Pakistan) hydromod@yahoo.com

3 Environmental Department, Govt. of   Punjab, Lahore (Pakistan) rizwanchemist@gmail.com

4Kinnaird College for Women Lahore (Pakistan) helen.khokhar@kinnaird.edu.pk

5Govt. College University, Lahore. fida0768@gmail.com

PJEST. 2023, 4(3); https://doi.org/10.58619/pjest.v4i3.117 (registering DOI)

Received: 06-May-2023 / Revised and Accepted: 19-June-2023 / Published On-Line: 28-June-2023

PJEST

ABSTRACT: Air pollution is one of the several environmental problems urbanization brings. One of the air contaminants that impacts human health is particulate matter (PM). The current study aimed to assess the relative risks and attributable proportions. It can be brought on by human exposure to PM2.5 and PM10 (PM with aerodynamic diameters ≤ 2.5 μm and ≤ 10 μm, respectively). AirQ+ software was used to modify the health effects of particles on human beings in terms of attributable percentage (AP). Environmental Protection Department (EPD), Punjab Bureau of Statistics, and Punjab Health Department provided input data on particulate concentration, health, and population. Findings indicated that PM2.5 with an average concentration of 106 ug/m3 per year makes up 54.04 % of the attributable proportion (AP) of age 30+ adults, all-cause mortality rate, and 46.31% AP of age 30+ adults with chronic obstructive pulmonary disease (COPD). AP to stroke mortality in adults age 25+ was 65.01% (BI-150), and 38.28% (BI-630) was in children aged 0-5 years, contributing to acute lower respiratory infection (ALRI) mortality. The attributable proportion to ischemic heart diseases (IHD) in adults age 25+ was found to be 56.19%. It was also found that PM10 with an average concentration of 163 ug/m3 contributes 44.05% AP to infant post-neonatal. There must be appropriate mitigating strategies for pollution reduction concentration to reduce the potential adverse effects of air on health particulates.

Keywords: Chronic obstructive pulmonary disease, particle matter, relative risk, public health

Introduction

A complex mixture of gaseous and particle pollutants, each harmful to human health, causes air pollution. Studies from across the world have consistently shown that air pollution is a significant modifiable risk factor for dramatically increased morbidity and mortality, even though the makeup of air pollution varies greatly depending on the source [1, 2]. Additionally, clinical research has typically demonstrated that PM air pollution has a more detrimental effect on health than its gaseous counterparts. PM negatively affects human health in many areas, including the cardiovascular system. Increased risk of death from cardiovascular disorders such as ischemic heart disease, heart failure, and ischemic/thrombotic stroke is linked to acute and chronic exposure to PM air pollution [2].

Although the health effects of air pollution are most severe in developing nations, the link between air pollution and mortality is still present even when pollution levels are much below goal limits in developed countries. According to the World Health Organization (WHO), PM air pollution ranks the 13th most common cause of death worldwide, causing an estimated 800,000 premature deaths annually [3]. PM may originate from both natural and artificial sources. Combustion in mechanical and industrial operations, automobile emissions, and cigarette smoke are examples of artificial PM sources [2-4]. Examples of natural sources are volcanoes, fires, dust storms, and sea salt aerosol.

The National Ambient Air Quality Standards (NAAQS) of Pakistan and the WHO’s recommended values for particle pollution are frequently exceeded in the metropolitan area of Lahore. Health problems can arise from fine and coarse particulate matter such as PM2.5 and PM10. Nearly half of Pakistan’s widespread disease and premature death is caused by indoor and outdoor air pollution, which accounts for around 6% of Pakistan’s GDP in terms of environmental damage [5]. Numerous industrial sources and road vehicles have increased because of urbanization and population growth. According to new data on exposure risk assessment and global exposure estimates, exposure to ambient PM has risen more than initially thought. The higher intensity of human activity and vehicle emissions significantly contribute to increased exposure to air pollution in megacities like Lahore. PM is regarded as one of the finest indicators for evaluating the health effects of ambient air pollution [3, 5, 6].

In several industries located both within and outside of the megacity of Lahore, automobiles are one of the primary sources of PM emissions in Lahore. From November through January—known locally as “smog season”— ambient air pollution in Lahore city increases significantly. Respiratory and cardiovascular conditions brought on by contaminated air can be fatal. A nation’s economic and health sectors are significantly impacted by air pollution. A mixture of small to medium-sized particles and liquid droplets is called particulate matter [2]. Natural and human activity are both sources of particulate matter. The particle matter can harm plants and people and stay in the air for a very long time [3]. Local sources, dispersion and long-range transport patterns, industrial activity, fuel combustion, local traffic activity, fire, and burning activities, prevailing meteorological conditions, land-use patterns, topography, and long-term climate conditions all influence PM10 concentrations in the atmosphere. All life forms in the surrounding environment are at risk from PM10 particles, which are also one of the main signs of air pollution. PM10 has become one of the primary air pollutants in urban, suburban, and even rural and isolated areas of the world since the advent of industrialization. Most metropolitan areas around the world have PM10 levels that are above WHO and national guidelines [6]. Congenital heart defects, ischemic heart disease, respiratory and circulatory mortality, preterm-birth risk, mutagenicity and DNA damage, fetal growth characteristics and poor birth outcomes, cancer risk, and inflammatory responses are just a few of the health issues that PM10 has been linked to in numerous reports [7]. Besides its detrimental effects on human health, PM10 also reduces atmospheric visibility as a critical element of smog, inhibits plant photosynthesis by depositing on their leaf surfaces, and alters soil physicochemical properties by depositing minerals and metals. It also has an impact on meteorological processes and atmospheric chemistry [8, 9].

There are numerous tools available for measuring various particle properties. Particle concentration and size are the two most crucial parameters of particles. The behavior of the particle in the surrounding air can be ascertained using a particle size analyzer. Compared to larger particles, sub-micron particles can stay in the atmosphere longer. Measurements of particle concentration are crucial for establishing emission limits, which protect the requirements for air quality. Instruments that measure particle size distribution use the behavior of particles (diffusion, aerodynamics, and optical and electrical mobility). Estimating the health effects of ambient particle matter in Lahore city was the primary objective of the present research. The relative risk of particle matter to various mortalities in various age groups in the research area was estimated using AirQ+.

Research Methodology

The methodology for the present study will include the following main steps:

Study Area

Fig. 1 shows the study area.

Fig. 1: Map of research area under investigation

Monitoring of PM2.5

Annual data of PM2.5 for the year 2022 has been collected from a fixed air quality monitoring station installed at the Town Hall building situated at the northern main commercial area of Lahore with several busy roads, markets, and a dense population. The monitoring station is located around 8 m from the ground, which is required to take samples of the air quality level in the area instead of representing any road or ground level pollution level. Moreover, the effect of wind speed and wind direction on air quality is accommodated with that much height in the Town Hall area. A detail of the instrument and monitoring technique is given in Table 1. Metals will be tested through Atomic Absorption Spectrophotometer (AAS)/ICP. Carbon, TOC. Particulate matter is the term given to the tiny particles of solid or semi-solid material in the atmosphere. Particulates in the atmosphere range in size across many orders of magnitude. The expression “particulate size” is based on particle behavior in the earth’s gravitational field. The equivalent aerodynamic diameter refers to a spherical particle of unit density (1 g /cm3) that falls at standard velocity. Because it determines atmospheric lifetime and lung deposition, size is a very important characteristic of particulates. Particulates ranging in size from <0.1 to 50 μ are called Total Suspended Particulates (TSP). Particulates more significant than 50 μ tend to settle out of the air, whereas particulate matter 10 μ in diameter and smaller are considered inhalable. This particulate matter is commonly referred to as PM10 [10].

The methodology for the collection and mass determination of particulate matter is relatively simple. Air is drawn through a size-selective inlet and some filter media. Particulates with aerodynamic diameters less than the cut-point of the channel are collected on the filter media. The mass

of these particulates is determined by the difference in filter weight before and after sampling. The concentration of the suspended particulate matter in the designated size range is calculated by dividing the weight gain of the filter by the volume of the air sampled.

PM2.5 low-volume samplers are like the PM10 high-volume samplers in that they also have a size-selective inlet, a filter, and a means of pulling air through the system; however, the PM2.5 samplers have some unique characteristics. The size-selective inlet comprises two separate size-selective inlets: the first is a PM10 inlet to remove all the larger particulates, followed by a PM2.5 selective inlet to exclude the particulates greater in diameter than 2.5 μm. A WINS (Well Impactor Ninety-Six) is the USEPA-recommended size-selective inlet for PM2.5 isolation. A 47 mm diameter Teflon filter replaces the large glass fiber filter used in PM10 instrumentation. PM2.5 filters are primarily used for particulate mass determinations, not characterizations, as are the larger PM10 filters. Particulate characterization is still done in conjunction with PM2.5, but species-specific traps such as denuders, foam plugs, cation and anion exchangers, absorbents, etc., are used [3, 6, 7].

Due in large part to the smaller filter and lower flow rates, PM2.5 samplers can be equipped with various size selective inlets. The Partisol Air Sampler from Rupprecht & Patashnick Company (Albany, NY) can be equipped with a PM1, PM2.5 sharp cut cyclone, PM2.5 with WINS impactor, PM10, United States TSP, or German TSP inlet for particulate analysis. The smaller filter used in PM2.5 samplers allows for advanced automation whereby a filter can be used, and a replacement filter automatically put into position for another sampling period [11, 12]. The Partisol line from Rupprecht & Patashnick and the RAAS line from Anderson have this capability. In addition, PM2.5 samplers can be equipped with an automatic weighing system for continuous real-time analysis.

Table 1.

Detail of ambient air quality analyzers and monitoring methods
Pollutant Instrument Range Method Detection Limit
 

 

PM2.5

 

 

BAM Analyzer

 

0~5 mg m-3

Gravimetric Method/Beta attenuation

Method

 

 

The required data was monitored and collected along with Pak Green Enviro- Engineering Laboratories and Environmental Protection Department (EPD). Model number DPM-6000 was assigned to the equipment used in the investigation based on the US-EPA’s beta attenuation method [13].

Contribution from Transport Sector

The contribution of different sectors like industry and vehicles will be calculated by gathering data from the said sectors. Data on cars will be taken from Excise and Taxation Department, and data on fuel usage in the city will be taken from OGRA, Punjab.

According to data from the country’s climate change ministry, transport accounts for more than 40% of the air pollution produced in Pakistan. Transportation has become a significant source of air pollution. Lahore is the most polluted city in Pakistan, with high levels of atmospheric particulate matter.

The concentration of major air pollutants in Pakistan, such as NOx, O3, and SO2, has also increased over the last two decades. During the year 2019, PM2.5 concentrations in Lahore revealed that almost every single day exceeded the WHO and national air quality standards. The extent, nature of contributing factors, and consequences still need to be more adequately understood [2, 4, 14].

Data on air quality was correlated with epidemiological variables such as attributable proportion, relative risk, baseline incidence, and proportion of death per 100,000 persons. The possibility of becoming ill because of coming into contact with a pollutant is a relative risk. The statistics data for the WHO-developed AirQ+ were used to determine the RR and BI values. The AirQ+ model does not account for wind speed or direction. Microsoft Excel was used to process the data, and the results were presented by looking at the central cure-lines of AirQ+ output graphs. The statistical techniques are used through SPSS (“Statistical Package for the Social Sciences”) 22nd version; the package is widely used in the social and behavioral sciences.

Results and Discussion

The results of the current research are presented in Table 2 and Table 3. The observed average annual of PM2.5 and PM10, mentioned in Table 2, were notably more significant than the recommended average yearly values of these pollutants by Punjab Environmental Quality Standards (PEQS) (i.e., 15 µg/m3 and 120 µg/m3 for PM2.5 and PM10 respectively) and by WHO (i.e., 10 µg/m3 and 20 µg/m3 for PM2.5 and PM10 respectively) for the quality of surrounding air. It is evident from Table 3 that even the seasonal assessment of PM2.5 concentrations was observed to be higher than that of WHO-recommended values. Several adverse health impacts have been associated with exposure to both PM2.5 and PM10 that can be inhaled, with some depositing throughout the airways. However, the locations of particle deposition in the lung depend on particle size and environmental conditions, as evident from the seasonal variation of PM2.5 concentration mentioned in Table 3. PM2.5 is more likely to travel into and deposit on the surface of the deeper parts of the lung, while PM10 is more likely to deposit on the surfaces

of the larger airways of the upper region of the lung. Particles deposited on the lung surface can induce tissue damage and lung inflammation. Long-term (months to years) exposure to PM2.5 has been linked to premature death, particularly in people with chronic heart or lung diseases, and reduced lung function growth in children [15, 16]. The effects of long-term exposure to PM10 are unclear, although several studies suggest a link between long-term PM10 exposure and respiratory mortality. The International Agency for Research on Cancer (IARC) published a review in 2015 that concluded that particulate matter in outdoor air pollution is responsible for lung cancer [3, 16].

Table 2: AirQ+ data presenting attributable proportion (AP) and relative risk (RR), including baseline incidence (BI)

Pollutant Annual               Mortality           BI per                AP

Average                 Type               100000              (%) (µg/m3)

RR
PM2.5 106            All (natural) cause  270                 54.04

(adults age   30+

2.175
years)
PM2.5 106            COPD for adults       89                  46.31 1.85
PM2.5 106            Stroke for adults      150                 65.01 2.89
PM2.5 106            ALRI for children   630                 38.28

age 0-5 years

1.62
PM2.5 106            IHD for adults         95.25               56.19 2.28
PM2.5 106            Respiratory               187.5               81.33 5.355
PM10 163            Post-neonatal           4400                44.05

infant

1.78
 

Table 3

Seasonal assessment of PM2.5 for each month
Season Spring Summer Fall Winter
Month Mar Apr may Jun Jul Aug Sep-Oct Nov Dec Jan    Feb
Concentration 105.1 102.2 72.17 71. 43.74 29.74 79.62  103 215.5 179 172   109.
(µg/m3) 3 23 .41 6 .71    4

Average                                                                106.9907 µg/m3

Further, Table 2 displays the results from the AirQ+ software against the average annual concentration of PM2.5 and PM10 for epidemiological variables, i.e., attributable proportion to baseline incidence of various mortalities:

  • Chronic Obstructive Pulmonary Disease (COPD) Mortality for adults
  • Ischemic Heart Disease (IHD) Mortality
  • All Causes Mortality for adults (aged 30+ years)
  • Stroke Mortality (among adults aged 25+ years)
  • Acute  Lower   Respiratory           Infection       (ALRI)   Mortality          (among children aged 0-5 years)
  • PM10 in post-neonatal mortality

COPD mortality for adults vs PM2.5 annual concentration:

Fig.2: Trend of COPD mortality excess cases for adults against the annual concentration of PM2.5

Figure 2 illustrates the COPD mortality cases between 2000 to 3000 for adults with AP of 46.51% for the year 2022 at RR of 1.85, which may be attributed to PM2.5 at a baseline incidence of 89/100,000 people in the study area polluted with an average annual concentration of 106.00 µg/m3 of PM2.5. The population at risk for COPD mortality is 5760000 in the study area. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3], which showed COPD mortality as a result of exposure to PM2.5 in Lahore with AP of 31.4% at RR of 1.458 during covid pandemic.

IHD mortality for adults vs PM2.5 annual concentration:

Fig.3: Trend of IHD mortality excess cases for adults against the annual concentration of PM2.5

Figure 3 illustrates the IHD mortality cases between 500 to 900 for adults with AP of 56.19% for the year 2022 at RR of 2.28, which may be attributed to PM2.5 at a baseline incidence of 95.25/100,000 people in the study area

polluted with an average annual concentration of 106.00 µg/m3 of PM2.5. The observed value of AP is the highest AP of PM2.5 to IHD mortality in the present research investigation. The population at risk for IHD mortality is 1476000 in the study area. Severe IHD illness was observed during that smog season (Nov to Jan) due to the rise of PM2.5 concentration presented in Table 3. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3], which showed IHD mortality as a result of exposure to PM2.5 of average annual concentration 55.99 µg/m3 in Lahore with AP of 40.8% at RR of 1.689 during covid pandemic.

All-cause mortality for adults vs PM2.5 annual concentration:

Fig.4: Trend of all-cause mortality excess cases for adults (age 30+ years) against the annual concentration of PM2.5

Figure 4 illustrates the all-cause mortality cases between 5000 and 7000 for adults (aged 30 +years) with AP of 54.04% for the year   2022 at RR of 2.175 that may be attributed to PM2.5 at a baseline incidence of 270/100,000 people in the study area with an ambient PM2.5 concentration of 106.00 µg/m3. The population (adults aged 30 +years) at risk to type of mortality is 4320000 in the study area. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3], which showed all-cause mortality as a result of exposure to PM2.5 of average annual concentration 55.99 µg/m3 in Lahore with AP of 24.17% at RR of 1.310 during covid pandemic.

ALRI mortality vs PM2.5 annual concentration:

Figure 5 illustrates the ALRI mortality cases between 2000 and 5000 with AP of 38.28% for the year 2022 at RR of 1.62 that may be attributed to PM2.5 at a baseline incidence of 630/100,000 people in the study area with an ambient PM2.5 concentration of 106.00 µg/m3. The population at risk of this type of mortality is 1416000 in the study area. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3], which showed ALRI mortality as a result of exposure to PM2.5 of average annual

concentration 55.99 µg/m3 in Lahore with AP of 34.11% at RR of 1.517 during covid pandemic. The findings showed that ambient PM2.5 was seriously harming the health of youngsters.

Fig.5: Trend of ALRI mortality excess cases against the annual concentration of PM2

Stroke mortality for adults vs PM2.5 annual concentration:

Fig 6: Trend of stroke mortality excess cases for adults against the annual concentration of PM2.5

When the average PM2.5 concentration in the ambient air of Lahore City was 106.00 g/m3, and the concentration of the pollutant increased nearly two times during the smog season (Nov to Jan) due to climatic changes. Figure 6 indicates that AP is 65.01% and the relative risk is 2.89 with BI of 150/100000. The population at risk of this type of mortality is 1476000 in the study area. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3]. High levels of air pollution can have a negative impact on stroke mortality. Investigations revealed the chemical makeup of PM2.5, which is more important than the bulk of particulate matter in causing death.

Post neonatal mortality all cause vs PM10 annual concentration:

Fig.7: Trend of Post neonatal mortality excess cases against the annual concentration of PM10

The current investigation assessed the impact of PM10 exposure on neonates as well. The study period’s average yearly exposure was 163.07 g/m3, the risk ratio (RR) was 1.78, and the attributable proportion (AP) was 44.05%. Mortality occurs at a base incidence rate of 4400 per 100,000 people. Figure

7 illustrates the mortality cases between 300000 and 900000; the population at risk is 336000 in the study area. The number of instances was considerably more significant than in the study by Malhi et al., 2022 [3], which showed post-neonatal mortality as a result of exposure to PM2.5

of average annual concentration 105 µg/m3 in Lahore with AP of 31.11% at RR of 1.45. The findings showed that higher PM levels than the standards caused negative health impacts in children and vulnerable people.

SOME SUITABLE RECOMMENDATIONS:

The atmospheric characteristics of temperature, atmospheric pressure, and humidity are interrelated and may be correlated with air pollution. Extreme air pollution during the autumn-winter season with particulate matter in the last decade. The reasons for this are not only transportation and industry but the use of solid fuel heating. Air pollution may affect temperature, atmospheric pressure, and humidity, which may cause climate change in the Ruse region. This influence has to be studied in detail further.

CONCLUSION

We have characterized the ambient air quality for criteria pollutants for Lahore, Pakistan. The aim of this research was to assess the impacts of air pollution on the people in Lahore. Higher levels of air pollutants, mainly particulate matter, have a negative effect on human health and dramatically increase the mortality rate from various diseases.

It was discovered that ambient air quality standards set by the WHO and PEQS still needed to be met for the pollutants PM2.5 and PM10 concentrations. The amount of particulate matter in the air is much more significant than WHO regulations, which has an adverse effect on mortality. PM2.5 has the most important reported number of instances that may be directly attributed to it. By bringing pollution control measures into place, it is necessary to take immediate action to reduce the rising pollutant concentration.

The monthly pattern of pollutants shows that AQI remained high during winter due to a relatively low washing effect (low rain), low wind speed, and high inversion. Moreover, the dominant wind direction from the southeast enabled the polluting steel industry to contribute to the pollution of Lahore in winter. With the negligible change, PM2.5 mass concentration remained above-defined threshold values in both pre-and post-monsoon periods. The cleaning effects of monsoon rains did not produce long-term impacts on air quality, which remained good to unhealthy before and after the monsoon.

The health risk associated with PM2.5 increases in total attributable deaths due to all-cause mortality, cardiovascular disease, respiratory disease, and hospital admission due to chronic bronchitis in the post-monsoon period. This mortality rate had increased.

Currently, active implementing policies to reduce ambient air pollution are needed to be revised and improved. Critical biological cell level investigations on patients’ mortalities due to ambient PM2.5 should be conducted to identify and assess inhaled PM pollutants’ concentration. New health-friendly counterpart chemicals of PM are to be introduced to lessen the possible negative effects of PM on health.

PM2.5 and PM10 concentrations need to be lowered below the respective permissible limits, and appropriate mitigation measures should be implemented to reduce the concentration of air pollutants.

For a better understanding of their effects on health, future studies should focus on identifying and quantifying chemical species of ambient air particles.

Author’s Contribution:

J.I., Conceived the idea and designed the research work; J.I., H.K., acquired data, and made all collections, J.I., H.K., R., F.R., performed the lab work; J.I., H.K., R., F.R., did the statistical work; J.I., H.K., wrote the primary draft; J.I., did the language and grammatical edits or Critical revision. J.I., did all the correspondence.

Funding:

The publication of this article was funded by no one.

Conflicts of Interest:

The authors declare no conflict of interest.

Acknowledgement:

The authors would like to thank the Chairperson of the Department of Physics Govt. Islamia Graduate College Civil Lines Lahore, for providing all the possible facilities during this research project.

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