Assessment of air pollution in South Kazakhstan using moss (Hylocomium splendens) biomonitoring technique and neutron activation analysis

Kazakhstan, due to intensive industrial development_, experiences severe air pollution, especially in urban areas. The moss biomonitoring technique has been applied to assess the level of air pollution in the most populous part of the country: the Almaty region and Shymkent, a city of republican significance. The content of 40 elements in Hylocomium splendens moss samples was determined by means of neutron activation analysis supplemented with the ICP-OES technique. Multivariate statistics were applied to detect and characterize the main air pollution sources. Among them can be highlighted a variety of natural (dust, sandstorms) and anthropogenic (fossil fuel combustion, vehicles, gas flaring in oil and gas production, mining and industrial enterprises) sources that contribute to air pollution. According to contamination factor values, the pollution level of the investigated area varied from suspected to severe. The potential ecological risk index calculated for selected elements revealed low ecological risk to human health in the Almaty region and moderate risk in Shymkent. A comparison of the biomonitoring data with results of similar studies performed in neighboring countries showed an increased level of air pollution in the investigated region.