For the first time in Almaty, the chemical composition of PM2.5 particles has been determined, allowing for the precise identification of key smog sources. The study was conducted by a group of Kazakhstani and international scientists, which included an expert from the Almaty Air Initiative. Over half of the pollution (54%) is linked to combustion processes, including emissions from combined heat and power plants (CHPs), residential heating, and secondary aerosols forming in the atmosphere.

Air sampling was conducted from August 2022 to July 2023. The use of an advanced mathematical modeling method (PMF) allowed the international team of scientists, including Almaty Air Initiative staff member Ravkat Mukhtarov, to isolate chemical “markers” and identify key sources of pollution. This method makes it possible to accurately determine the contribution of each source — from coal combustion to tire wear.

Key findings of the study that change our understanding of the smog:

  • Coal and biomass combustion — 34% CHPs and boiler houses (18%), together with residential heating (16%), account for more than a third of the pollution. Scientists emphasize that due to low air mixing in winter, the local burning of coal and firewood has a critical impact on the health of the city’s residents.
  • Pollution accumulation effect — 20% Due to Almaty’s geographical features (its location in a basin) and a low planetary boundary layer height (PBLH), pollutants do not disperse. Instead, they accumulate and engage in chemical reactions, increasing the air’s toxicity. This “cocktail” is dominated by traces of coal and biomass combustion, as well as industrial activity.
  • Road dust — 32% This is the natural background of urban pollution, constantly present in the air due to city dynamics: traffic, construction work, and population activity. It includes soil particles, as well as abraded asphalt, tires, and brake pads. The main sources of this dust are major highways (Al-Farabi Avenue, Eastern Bypass Road), where the traffic flow constantly kicks microscopic particles up into the air. Essentially, every third dangerous particle in our lungs is ground-up asphalt and rubber.
  • Vehicle exhaust gases — 14% Direct emissions from fuel combustion in engines account for 14%. However, transport plays a key role in the secondary “resuspension” of settled road dust into the human breathing zone.

Zhuldyz Saulebekova,  of the Almaty Air Initiative foundation:

“For me, as a mother of a child with special needs, the results of this study are a serious wake-up call. We have seen that PM2.5 is a complex cocktail of chemical compounds. Heavy metals, including lead and aluminum, have been detected within the particles. Their accumulation in the body is directly linked to the development of neurological diseases and impaired brain development in children.

Thanks to the sensor network, we understand the level and scale of the smog in the city, and now we also know exactly what enters our lungs and bloodstream. This allows us to draw precise conclusions about which sources generate this pollution.

Smog in Almaty is the result of the simultaneous impact of multiple sources. Therefore, solutions must be systemic — from reducing coal heating to minimizing dust formation and controlling transport emissions through changes in city management and infrastructure.”

The study is based on air samples collected in the southern part of the city — on the campus of Al-Farabi Kazakh National University. This is a densely built-up area with a massive traffic load. However, the scientists’ conclusion raises serious concerns: even in this “upper” part of the city, far from industrial zones, the contribution of coal smoke (from CHPs and residential areas) remains critically noticeable. Almaty Air Initiative experts emphasize: if the impact of coal is so evident in the southern districts, then in the lower part of the city — in close proximity to the CHPs and vast residential sectors — the situation could be exponentially worse.

The study’s authors proposed specific measures divided into four categories:

  • For CHPs: An urgent transition to gas and the installation of modern filters (based on EU experience, this reduces particulate matter emissions by 90%).

  • For the residential sector: Banning the sale of coal, providing gas subsidies, and insulating homes to reduce heat loss and consequently lower fuel demand.

  • For transport: Developing public transport and micromobility, as well as implementing strict vehicle inspection requirements.

  • For the city: Implementing an annual PM2.5 target level (25 µg/m³) and expanding the monitoring network to understand whether these measures are working.

A detailed breakdown of the study is published on the Almaty Air Initiative website: https://air.org.kz/ru/research/osnovnye-istochniki-vybrosov-pm2-5-v-almaty/

Reference: The study “Dominant sources of PM2.5 in Kazakhstan’s urban cities: A PMF and HYSPLIT-based study for air quality management in Central Asia” is published in the international scientific journal Urban Climate and is available at the following link: https://www.sciencedirect.com/science/article/abs/pii/S2212095525004225?via%3Dihub

The authors of the study are Kazakhstani scientists: Kazbek Tursun, Anara Omarova, Olga Ibragimova, Bauyrzhan Bukenov, Madina Tursumbayeva, Ravkat Mukhtarov, Ivan Radelyuk, Serpil Yenisoy, Duran Karakaş, Hatice Ergin, Ferhat Karaca, Nasiba Baimatova.

PM2.5 refers to microscopic particles that easily penetrate deep into the lungs and can enter the bloodstream. According to international medical studies, long-term exposure to PM2.5 is associated with an increased risk of cardiovascular disease, lung disease, and premature mortality.