Environmental Risk Assessment from 2018 to 2022 for Kota, Rajasthan (India)

Particulate matter pollution in the metropolis has become an international concern because of its dangerous short and long-term effects on humans and the environment. This research aims to quantify particulate matter's severe impact on inhabitants and identify the ecological environment risk category of Kota city, Rajasthan (India), throughout the selected study period from 2018 to 2022 for four years. Human health risk assessment has been assessed through AirQ+ software (WHO invented), while ecological hazard risk categories were recognised through risk quotient (RQ). The present scenario of particulate matter concentration is compared with standards given by different regulating agencies (WHO, USEPA, and Indian NAAQS) to verify particulate matter pollution. The current particulate matter concentration levels of Kota city are also compared with different regional cities of Rajasthan (India), namely, Jaipur, Udaipur, Ajmer, Pali, Alwar, and Jodhpur. The dust ratio (PM 2.5 /PM 10 ) is computed for Kota and regional cities to validate the increasing levels of fine particulates than the larger ones. The four-year average concentration of PM 10 and PM 2.5 were 121 and 58 µg/m 3 , respectively, with a dust ratio of 0.48. Particulate matter concentrations (PM 10 and PM 2.5 ) are violating the standards set by environmental agencies during the study period. The mean risk quotient (RQ) is 2.02 for PM 10 and 1.43 for PM 2.5 , which implies a high-risk hazard category (RQ > 1) in the ecological environment of Kota city. The mortality cases evaluated from AirQ+ software were 5024 for all natural causes, 885 for lung cancer, 272 for acute lower respiratory infection, 464 for COPD, 2060 for IHD, and 1880 for stroke. The number of hospital admissions was 1485 for respiratory disease, 58 for cardiovascular disease, and 784 for


Introduction
2][3] The severity of the problem varies in industrial and developing countries. 4,57][8] Many of the less developed countries becoming urbanised and industrialised do not have the resources or enough technologies to dispose of the pollutants with minimal environmental impacts. 5,9Humankind's ability to spontaneously assess and manage health risks has become fundamental to survival in today's changing environment. 10,11rticulate matter pollution is now a serious worldwide concern due to its severe consequences on an ecosystem's biotic and abiotic components. 12,13[16][17][18] Fine particulate matter is getting more attention because of its small size.It has heterogeneous compositions of liquid and solid particles suspended in the environment.The size of dangerous particulates varies from large to too-small. 7,19Some particulates are so large that they can be watched even through the bare eye, although the rest are so minute that they could only be monitored with the help of an electron microscope. 20,21PM are broadly classified into two categories according to their aerodynamic diameter, i.e., PM 2.5 (Día ≤2.5 µm) and PM 10 (Día ≤10 µm). 3,22tural and man-made activities are answerable for the worst air quality. 5,23.5][26] vehicular emissions. 25,27power generation. 8,28oil refineries, 25 and stubble and wood burning are the leading causes of particulate matter formation. 29,30e undesired detrimental effect of particulates on the health of humans has mild, moderate, or severe impacts according to their concentration level and duration of exposure.It has become a significant environmental risk factor for all-cause and disease-specific morbidity & mortality. 31Older age, Children, and pregnant women are susceptible to the exposure. 32,33PM 2.5 exposure causes mortality fromlung cancer, 34 all-natural causes in adults (30+ years), chronic pulmonary obstructive disease (COPD), 11 acute lower respiratory infection (ALRI), 32 stroke, 35 ischemic heart disease (IHD), 34 and Shortterm impacts increase hospital admissions from diseases related to respiratory, cardiovascular disease (CVD), stroke, and adult mortality. 36e ultimate objective of this work is to measure particulate matter's severe impact on inhabitants and identify the ecological environment risk category of Kota city, Rajasthan (India), during the observation period of four years (2018-2022).Not sufficient studies were available in the literature for Kota to quantify environmental risk.The educational hub of the Rajasthan state (India), Kota, is a rapid-growing metropolis with two million inhabitants.Kota is suffering from the harmful impact of particulate matter pollution.

Study Area & Research Methodology
Kota, an industrial and educational district of Rajasthan, ranks 16 th in terms of population, 24 th in a geographical area, and 7 th in population density in the Rajasthan State of India.The population of Kota was 19, 51, 014 in 2021 as per the census of India, 2011. 37PM 10 and PM 2.5 are the parameters selected for the study.Four-year air quality data iscollected from January 2018 to December 2021.Seven monitoring sites on air quality were utilised to obtain the data to determine the city's air quality deterioration.Air quality stations for Kota are mentioned in Table 1.The average PM 10 and PM 2.5 concentrations are also compared with other regional districts of Rajasthan, namely, Jaipur, Udaipur, Ajmer, Pali, Alwar, and Jodhpur, with an additional 10 continuously monitoring air quality stations, including one continuous air quality station for Kota.The research methodology for the study is exhibited in Figure 2. Human health risk assessment has been evaluated with the help of AirQ+ software (WHO invented), while ecological hazard risk categories were recognised through risk quotient (RQ).

Fig. 2:
Step-by-step procedure followed in this study to complete the research work.
A comparison with different regional cities, namely, Jaipur, Udaipur, Ajmer, Pali, Alwar, and Jodhpur, has also been done for PM 2.5 andPM 10 concentrations.The dust ratio (PM 2.5 /PM 10 ) is computed for Kota and regional cities to validate the increasing levels of fine particulates than the larger ones.The fine particles have the capability of penetrating deeper into the respiratory tract which has more severe consequences for human beings than the large ones.The standards for PM 10 and PM 2.5 prescribed by different agencies worldwide are shown in Table 2.

Environmental Risk Assessment
This study implements the environmental risk assessment for Kota due to particulate matter with the help of ecological environmental risk and human health risk assessments.Risk Quotient has been estimated to determine the hazard risk category for ecological environmental risk assessment.At the same time, the AirQ+ software is used to estimate human health risk analysis.

Ecological Environmental Risk
Ecological environment risk is a semi-qualitative risk based on particulate matter's physical and chemical characteristics to evaluate the ecological environment's probable risk category (Table 3).A risk Quotient is calculated with the help of the following equation.

Results and Discussion
The results of this study reveal that PM 2.5 and PM 10 concentrations for Kota, Jaipur Ajmer, Udaipur, Pali, Jodhpur, and Alwar of Rajasthan werehigher than those recommended by different agencies worldwide shown in Table 2. Particulate Matter concentrations for Kota, Jaipur, Ajmer, Udaipur, Pali, Jodhpur, and Alwar are shown in Figure 3.The air pollutants concentrations went down, and inhabitants had clean air to breathe.Several studies on air quality reveala meaningful impact of lockdown restrictions on the air quality globally, 2,50-52 and a reduction in particulate matter pollution level was also seen in 2020 for Kota, also leading to low values of RQ for PM 10 and PM 2.5 .The risk quotient values for Kota were calculated with the help of equation 1, which is mentioned in Table 5.The PM 10 and PM 2.5 for Kota were computed through the average of all monitoring stations' concentrations (Table 4).RQ values for each year for Kota city are evaluated from average PM 10 and PM 2.5 concentrations.

Human Health Risk Assessment
The average annual PM 10 and PM 2.5 were 123 and 57 µg/m 3 , respectively, during the observation of four years for Kota city.The particulate matter concentration plays a vital role in conducting the impact analysis through software (AirQ+).The estimated effects of PM 10 and PM 2.5 are mentioned in Table 6.
The average lung cancer mortality for Kota city is 885 due to PM 2.5 exposure over a long period.
The average COPD mortality for Kota city is 464 due to PM 2.5 exposure for a long period.
The average IHD mortality for Kota city is 2060 due to PM 2.5 exposure for a long period.Stroke mortality was leading at the AQS-4 location (2171 deaths), followed by the AQS-3 location (1908 deaths), the AQS-5 location (1887 deaths), the AQS-2 location (1865 deaths), and 1777 for the AQS-1, AQS-6, and AQS-7 locations.The average stroke mortality for Kota city is 1880 due to PM 2.5 exposure for a long period.The postneonatal infant mortality due to PM 10 exposure for a long period was maximum at the S-4 location with 426146 deaths, followed by the AQS-3 location (364196 deaths), AQS-5 location (354092 deaths), AQS-6 (354095 deaths), AQS-2 (341237 deaths), AQS-1 (325475 deaths), AQS-7 (325475 deaths).The average postneonatal infant mortality for Kota city is 355816 due to PM 10 exposure for a long period.
The chronic bronchitis incidence in adults was 16151 for the AQS-4 location, 14719 for the AQS-3 location, 14460 for the AQS-5 and AQS-6 locations, 14119 for the AQS-2 location, and 13685 for the AQS-1 and AQS-7 locations.The average chronic bronchitis incidence in adults for Kota city is 14469 due to PM 10 exposure for a long period.The prevalence of bronchitis in kids was foremost at the AQS-4 location (882 cases), followed by the AQS-3 location (782 cases), the AQS-5 and AQS-6 locations (765 cases), the AQS-2 location (743 cases), and 715 for the AQS-1, and AQS-7 locations.The prevalence of bronchitis in kids in Kota city is 767 due to PM 10 exposure for a long period.The hospital admission for respiratory disease (HA-RD) from PM 2.5 exposure for a short period was maximum at the AQS-4 location with 2153 cases, followed by the AQS-3 location (1532 cases), AQS-5 location (1487 cases), AQS-2 (1442 cases), AQS-1, AQS-6, and AQS-7 (1260 cases).The average HA-RD for Kota city is 1485 due to PM 2.5 exposure for a short period.
The average all-cause mortality in adults for Kota city is 784 due to PM 2.5 exposure for a short period.The asthma symptoms in asthmatic kids due to PM 10 exposure for a short period were maximum at the AQS-4 location with 430 cases, followed by the AQS-3 location (362 cases), AQS-5 location (352 cases), AQS-2 (338 cases), AQS-1, AQS-2, and AQS-7 (321 cases).The mean asthma symptoms in asthmatic kids for Kota city is 349 due to PM 10 exposure for a short period.
The EAP and ENACPL for long and short-term effects of PM 2.5 and PM 10 on humans.AirQ+ software gave the results at the ambient leveltabulated in Tables 7 and 8, respectively.Notably, the higher concentration of particulate matter station has high ENACs, EAP and ENACPL.The spatial variability maps for mortality due to all-natural causes (Figure 6), lung cancer (Figure 7), ALRI (Figure 8), COPD (Figure 9), IHD (Figure 10), and stroke (Figure 11) have been prepared through ESRI ArcGIS software.It can be easily verified through these maps that the peoples of the nearby area of station AQS-4 (Regional Office, RSPCB) are highly vulnerable to the adverse effect of particulate matter as this station has the peak average PM 10 and PM 2.5 concentrations among all.
The AQS-4 station is only 3.5 km from the city's center, the aerodrome circle.The AQS-6 station  (Sewage Treatment Plant, Balita) is situated on the outer periphery of Kota city, almost 12 km from the city's center, the aerodrome circle, and it is the least susceptible to the adverse effect of particulate matter due absence of air pollution sources.

Conclusion
The present study reveals that the particulate matter concentration for Kota during the observation period is clearly violating the standards prescribed by the different global agencies, namely, WHO, USEPA, and Indian NAAQS.Particulate matter pollution is identified as the foremost cause of air pollution in Kota.The air quality monitoring station situated at Regional Office, RSPCB shows the maximum degradation in the air quality due to the presence of different micro, small and medium enterprises.
Transportation of goods with the help of heavy vehicles puts an additional deterioration in the ambient air quality.The amount of fine particulate matter (PM 2.5 ) gradually increases in Kota city as the dust ratio shows an increasing trend during the observation period.The fine particles have the capability of penetrating deeper into the respiratory tract and creating many adverse effects on the human body.Hence, it is becoming a more serious concern for the inhabitants of Kota city.

Fig. 3 :
Fig. 3: The concentration of particulate matter in prominent regional cities nearby Kota.The annual particulate matter concentrations are mentioned in Table4for each sampling location in the city.The PM 10 concentrations for Kota were 152, 118, 97, and 119 µg/m 3 in 2018, 2019, 2020, and 2021, respectively.The PM 2.5 concentrations for Kota were 55, 58, 50, and 67 µg/m3 in 2018, 2019, 2020, and 2021, respectively.The dust ratio for Kota were 0.36, 0.49, 0.52, and 0.56 in 2018, 2019, 2020, and 2021 respectively.An increasing trend has been seen inthe dust ratio duringthe observation of four years.The dust ratio varies from place to palace and year to year.The PM 2.5 concentration gradually increased during observation except in 2020 due to Covid-19 lockdown restrictions all over India in 2020.49,50

Table 4 : Annual PM 10 and PM 2.5 data for each station of Kota city, Rajasthan (India).
49,50A decreasing trend has been observed for PM10till 2020, but it again starts increasing in 2021 with tremendous speed.Several studies suggest that these restrictions help to improve air quality worldwide.The annual particulate matter concentrations are exhibited in Figure4for each sampling location in the metropolitan area.121and57 µg/m 3 were the mean PM 10 and PM 2.5 concentration,respectively.At the same time, the average dust ratio was 0.48.The dust Ratio (PM 2.5 / PM 10 ) in prominent places of Rajasthan State, India, is graphically presented in Figure5.The dust ratio for Kota city is gradually rising from 0.36 to 0.51.The dust ratio for Kota was 0.36 in 2018, 0.49 in 2019, 0.51 in 2020, and 0.56 in 2021.High dust ratio values confirm the higher concentration of fine particles (PM 2.5 ) compared to larger particles (PM 10 ).The fine particles have the capability of penetrating deeper into the respiratory tract and creating many adverse effects on the human body.Hence, it is becoming a more serious concern for the inhabitants of Kota city.
*NA stands for not availability of data.

Table 6 : Station Wise Distribution of ENACs for Disease Caused by PM 10 and PM 2.5 .
*ENAC stands for the estimated number of attributable cases.

Table 8 : Station Wise Distribution of ENACPL for Disease Caused by PM 10 and PM 2.5.
*ENACPL stands for the estimated number of attributable cases per lac population.
The environmental risk assessment of particulate matter results shows that neither the state capital, Jaipur, nor other prominent cities such as Kota, Ajmer, Udaipur, Pali, Jodhpur, and Alwar of Rajasthan are competent to maintain or keep below the particulate matter concentration within the safe limits prescribed by different agencies worldwide.In other words, metro cities of Rajasthan state are suffering from regularly growing levels of particulate matter pollution.The ecological environment of Kota city is under massive threat as the hazard risk is in the high category (RQ>1) for PM 10 and PM 2.5.Ecological environment risk assessment suggests that Kota inhabitants are highly vulnerable to negative impacts caused by particulate matter.The order of mortality cases for Kota city evaluated through AirQ+ software is the all-natural cause (4565-6365) > IHD (1962-2333) > stroke (1776-2171) > lung cancer (809-1102) > COPD (436-542) > ALRI (255-316).Improving the management of solid waste, restricting open burning, increasing green beltways, prohibiting old vehicles, planting different plants, and shifting towards clean energy vehicles would effectively lessen the consequence of particulate matter on people.