Air Quality and Emission Trends Following the 2021 Environmental Code Reform in Kazakhstan Across Regions and Industrial Sectors

Abstract

The 2021 revision of the Environmental Code of the Republic of Kazakhstan was introduced to align with the World Health Organization (WHO) air quality guidelines and the national carbon neutrality strategy for 2060. The revised Code reflects a transformation of environmental governance, including the transition towards a low-carbon and climate-oriented policy framework, the tightening of air quality standards, the strengthening of environmental monitoring, the expansion of region-specific regulatory mechanisms, and increased emphasis on the implementation of Best Available Techniques (BAT). This study presents a comparative analysis of atmospheric pollutant emissions across regions and industrial sectors, including major pollutants such as PM2.5, SO2, CO, NO2, and others. The analysis considers ambient air quality indicators, pollutant composition, the chemical composition of atmospheric precipitation, regional industrial profiles, and changes observed during the reform period. The findings demonstrate substantial regional and pollutant-specific heterogeneity in air-quality dynamics. Although stationary-source emissions decreased by approximately 5–6% between 2021 and 2024, no statistically significant improvement in the assessed ambient-air indicators was identified between 2021 and 2025. Persistent high pollution levels and episodic particulate matter exceedances remained evident in several cities. These findings provide an empirical basis for further assessment of the environmental outcomes of the revised Environmental Code.