Search

Several epidemiological studies have shown a close relationship between the mass of particulate matter (PM) and its effects on human health. This study reports the identification of inorganic and organic components by attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) analysis in PM 10 and PM 2.5 filters collected from three air quality monitoring stations in the city of Palermo (Sicily, Italy) during non-Saharan dust events and Saharan events. It also provides information on the abundance and types of water-soluble species. ATR-FTIR analysis identified sulfate, ammonium, nitrate, and carbonate matter characterized by vibrational frequencies at 603, 615, 670, and 1100 cm -1 (SO 4 2- ); at 1414 cm -1 (NH 4 + ); at 825 and 1356 cm -1 (NO 3 - ); and at 713, 730, and 877 cm -1 (CO 3 2- ) in PM 10 and PM 2.5 filters. Moreover, aliphatic hydrocarbons were identified in the collected spectra. Stretching frequencies at 2950 cm -1 were assigned to CH 3 aliphatic carbon stretching absorptions, while frequencies at 2924 and 2850 cm -1 indicated CH 2 bonds. In filters collected during Saharan dust events, the analysis also showed the presence of absorbance peaks typical of clay minerals. The measurement of soluble components confirmed the presence of a geogenic component (marine spray and local rocks) and secondary particles ((NH 4 ) 2 SO 4 , NH 4 NO 3 ) in the PM filters. ATR-FTIR characterization of solid surfaces is a powerful analytical technique for identifying inorganic and organic compounds in samples of particulate matter.