Resumo:
Atmospheric particulate matter (APM) is one of the main urban pollutants, composed of solid and liquid particles suspended in the atmosphere, emitted by vehicular and industrial sources. This study investigated carbonyl compounds (CC), both in free form and bound to sulfur (hydroxyalkylsulfonic acids - HASA), in APM samples with particle sizes of 2.5 μm and 10 μm collected in the subsoil of the Lapa station, in Salvador - Bahia, in 2005 and 2010, using ultrafast liquid chromatography with a diode array detector (UFLC-DAD). The analytical methodology demonstrated good figures of merit for the determination of 16 CC. In the MP10 samples, 13 CC were quantified, in the free and bound form HASA, and for the MP2.5, 14 CC were quantified in the free form and 13 CC in the bound form HASA. Crotonaldehyde was only quantified in PM2.5, and heptanal and cyclohexanone were not determined. The highest concentrations were obtained for the sum of acetone + acrolein, while the lowest were for the sum of isobutyraldehyde + butyraldehyde. In both 2005 and 2010, CC were generally in higher concentrations in the free form, with the exception of the sum of acetone + acrolein, which were higher in the bound form HASA. In the years 2005 and 2010, CC concentrations in PM10 showed an increase in 2010. The highest concentrations of CC were on Monday, in the free and bound forms, in both particle sizes studied. The results highlight the relevance of free and bound CC (HASA) due to their toxicity and carcinogenicity. This study represents a significant contribution to environmental chemistry, reinforcing the need for CC regulation in the APM and the adoption of public policies to improve air quality and mitigate health risks.
