Source identification and exposure assessment to PM10 in the Eastern Carpathians, Romania

Observations of particulate matter less than 10 µm (PM₁₀) were conducted from January to December in 2015 in the Ciuc basin, Eastern Carpathians, Romania. Daily concentrations of PM₁₀ ranged from 10.90 to 167.70 µg/m³, with an annual mean concentration of 46.31 µg/m³, which is higher than the European Union limit of 40 µg/m³. Samples were analyzed for a total of 21 elements. O, C and Si were the most abundant elements accounting for about 85% of the PM₁₀ mass. Source identification showed that the elemental composition of PM₁₀ is represented by post volcanic activity, crustal origin, and anthropogenic sources, caused by the resuspension of crustal material, sea salt and soil dust. The average PM₁₀ composition was 72.10% soil, 20.92% smoke K, 13.84% salt, 1.53% sulfate and 1.02% organic matter. The back-trajectory analysis showed that the majority of PM₁₀ pollution comes from the West, Southwest and South.