The impact of industrial CO₂ emissions on PM2.5 air pollution in Central Asian countries: A panel data analysis
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Author(s)Sobirjon S. RuziyevLink to ORCID Index: https://orcid.org/0000-0003-4375-1421
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Hulkar R. TurobovaLink to ORCID Index: https://orcid.org/0000-0003-4298-2412
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Sokhibmalik KhomidovLink to ORCID Index: https://orcid.org/0000-0002-8617-3740
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Dilnoza DjuraevaLink to ORCID Index: https://orcid.org/0000-0002-4331-4849
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Shaxnoz B. BoltayevaLink to ORCID Index: https://orcid.org/0009-0003-3481-3456
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Fozil XolmurotovLink to ORCID Index: https://orcid.org/0000-0003-2745-1832
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DOIhttp://dx.doi.org/10.21511/ee.17(3).2026.04
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Article InfoVolume 17 2026, Issue #3, pp. 49-63
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3 Downloads
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Creative Commons Attribution 4.0 International License
Type of the article: Research Article
Abstract
Central Asian countries face acute air quality challenges, with PM2.5 concentrations in major cities exceeding World Health Organization guidelines several times over, while industrial CO2 emissions continue to rise alongside economic development. Understanding the empirical linkage between these pollutants is essential for designing integrated environmental policies. The purpose of this study is to assess the impact of industrial CO2 emissions on PM2.5 air pollution in five Central Asian countries – Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan – using balanced panel data for the period 2000–2020 (N = 105) obtained from the World Bank’s World Development Indicators. Pooled OLS, fixed effects, and random effects estimators were applied, with GDP per capita, urbanization, and energy intensity as control variables. Model selection was based on the Hausman test, and robustness was verified through ten alternative specifications. The random effects model (Hausman χ2 = 0.412, p = 0.521) reveals a statistically significant positive relationship: a one million metric ton increase in industrial CO2 emissions is associated with a 0.87–0.89 µg/m3 rise in mean annual PM2.5 concentration (p < 0.01). The coefficient remains stable across all robustness checks (0.823–0.923). GDP per capita shows a significant negative effect (−1.92, p < 0.05), supporting the Environmental Kuznets Curve hypothesis, while energy intensity has a positive effect (p < 0.05). Country-specific effects reveal substantial heterogeneity, with Tajikistan exhibiting the highest baseline PM2.5 (+26.25 µg/m3 above Kazakhstan) and Turkmenistan the lowest (+7.49 µg/m3). These findings confirm the co-pollutant hypothesis and justify integrated climate-air quality policies with country-specific strategies.
Acknowledgments
The authors would like to thank the anonymous reviewers for their constructive comments and suggestions that helped improve this manuscript.
- Keywords
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JEL Classification (Paper profile tab)C23, Q53, Q54, O13
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References45
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Tables17
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Figures0
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- Table 1. Descriptive statistics
- Table 2. Correlation matrix
- Table 3. Panel unit root test results (CIPS test)
- Table 4. Cross-sectional dependence test results
- Table 5. Heteroskedasticity test results
- Table 6. Serial correlation test results
- Table 7. Multicollinearity diagnostics (VIF)
- Table 8. Summary of diagnostic tests
- Table 9. Panel regression results: CO2 emissions and PM2.5 concentration
- Table 10. Hausman specification test results
- Table 11. Country-specific fixed effects
- Table 12. Robustness check: Alternative standard error specifications
- Table 13. Robustness check: Alternative model specifications
- Table 14. Robustness check: Subsample analysis
- Table 15. Robustness check: Outlier analysis
- Table 16. Summary of CO2 coefficient estimates across specifications
- Table 17. Summary of hypotheses testing results
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Evaluating the effects of IFRS 9 on Jordanian banks’ credit and financial metrics
Amer Morshed
doi: http://dx.doi.org/10.21511/bbs.19(4).2024.06
Banks and Bank Systems Volume 19, 2024 Issue #4 pp. 70-83 Views: 6758 Downloads: 681 TO CITE АНОТАЦІЯAdopting International Financial Reporting 9 is critically relevant as it significantly transforms accounting practices, particularly in credit risk management, for banks in Jordan. The primary purpose of this study is to examine the impact of implementing International Financial Reporting 9 on the financial performance and credit risk management practices of Jordanian banks. A quantitative analysis was conducted using the Difference-in-Differences approach and Fixed Effects models on data from 19 banks operating between 2012 and 2022.
The results indicate that the adoption of International Financial Reporting 9 led to a substantial increase in loan loss provisions, with a mean increase of 0.25 (t-value = 18.00). This increase in loan loss provisions negatively affected profitability metrics such as Return on Assets and Return on Equity, which showed mean decreases of 0.0857 (t-value = 4.22) post-implementation. Despite the negative impact on profitability, the findings also highlight improvements in financial transparency and stability due to more accurate credit risk assessment.
While the adoption of International Financial Reporting 9 imposes operational and financial challenges, it enhances the robustness and clarity of financial reporting in Jordanian banks. -
Exploring the environmental Kuznets curve for CO2 and SO2 for Southeast Asia in the 21st century context
Patrick Wijaya Tjoek , Pei-Ing Wu
doi: http://dx.doi.org/10.21511/ee.09(1).2018.01
Environmental Economics Volume 9, 2018 Issue #1 pp. 7-21 Views: 4102 Downloads: 826 TO CITE АНОТАЦІЯThis study aims to investigate the relationships between economic development and environmental degradation regarding the emissions of CO2 and SO2 in Southeast Asia (SEA). The pooling data consist of 10 countries, Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Singapore, the Philippines, Thailand, and Vietnam, in the period 2003-2012. Furthermore, income elasticity of CO2 and SO2 emissions is computed for each country to observe the sensitivity of environmental degradation through the emissions of CO2 and SO2 brought by economic development.
The results indicate that CO2 displays an inverted U-shape pattern, whereas SO2 has decreased at an increasing rate since 2003. It is expected that SO2 will increase as the SEA economies further develop. The turning points for both CO2 and SO2, indicate that the current SEA income level has not reached the turning point. The income elasticities show that income elasticities for CO2 are positive for all 10 countries. Both Singapore and Malaysia are classified as countries with high income. However, Singapore, with 0.64%, has the highest income elasticity, and Malaysia, with 0.15%, has the second lowest. There is no indication that wealthy countries have a significant impact on CO2 through economic development. Income elasticities for SO2 of each country are all negative. This suggests that SO2 is an inferior good. Brunei, with 8.41%, has the most sensitivity toward change in SO2 emissions, whereas Myanmar, with only 0.58%, is the least sensitive to SO2 emissions. -
A financial performance-based assessment of SMEs’ competitiveness – an analysis of Hungarian and US small businesses
Vivien Csapi ,
Virgínia Balogh
doi: http://dx.doi.org/10.21511/ppm.18(3).2020.37
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A panel data model was tested on Hungarian small and medium-sized enterprises (SMEs) and US SMEs. The collected data cover the period between 2013 and 2017. As a result of the applied panel regression, those variables were successfully identified that drive and could predict financial performance measures related to competitiveness. The research found a significant difference between the two-sample dataset results, which differences can be connected to country, industry, and, in general, to economic development characteristics.
The results provide decision-making support and hint about the managerial tools and techniques aiming to control the firm characteristics, performance, and, eventually, firm-level competitiveness. Based on the results, further research can be dedicated to the development characteristics of firm-level competitiveness and the analysis of the relationship between the competitiveness dimensions and competitiveness itself.Acknowledgment
The research was financed by the Higher Education Institutional Excellence Programme of the Ministry for Innovation and Technology in Hungary, within the framework of the 4th thematic programme „Enhancing the Role of Domestic Companies in the Reindustrialization of Hungary” of the University of Pécs.
