Concentration of aliphatic and polycyclic aromatic compounds in atmospheric samples collected around a petrochemical site at São Paulo, Brazil.

Some of organic compounds emitted during incomplete combustion have adverse impacts on human health. N-alkanes and polycyclic aromatic hydrocarbons were abundantly emitted by fossil fuel combustion. The hopanes were presented in crude oil and engine lubricating oil. Particulate matter samples and gaseous samples were collected simultaneously in 2015 at a site next to a petrochemical site located in Santo André city, metropolitan area of São Paulo. Samples were analyzed for elemental and organic carbon (EC and OC), hopanes, n-alkanes and polycyclic aromatic hydrocarbons (PAH). The range for total suspended particle (TSP) varied from 26 to 99 μg m-3. One day before the sampling, it was reported a burning inside the petrochemical industry that probably it was affected the sample composition. Fifteen hopanes were identify in all the samples. The hopane with high concentration was C29αβ (2.2 ng m-3) in PM and C27-Ts (1.6 ng m-3) in PUF. The sum of isomers was greater for 17α(H), 21β(H) these results indicate that the hopanes were emitted by the petroleum completely mature (Alves et al., 2016). The series of n-alkanes comprising between C11 and C35 were identify in all the samples. C11 (40 ng m-3) was predominant for PM and C19 (105 ng m-3) was majority for PUF. For the both phases, the compounds less than C25 presented high concentration; petroleum residues commonly range between C15 and C26. For total n-alkanes concentration were 263 ng m-3 and 453 ng m-3 for PM and PUF, respectively. The carbon preferential index (CPI), a parameter to indicate a major contribution of petroleum residues in the samples, was 1.6 and 1.3 for PM and PUF, respectively. N-alkanes with influence of petroleum emissions present the CPI ~ 1 (Simoniet, 1984). Fifteen PAH were quantify in this study. The PAH with low molecular weight were predominant in PUF, while high molecular weight were majority in PM phase. Phenanthrene presented the highest concentration (1.5 ng m-3) in PUF and benzo(b)fluorantene was dominant (1.2 ng m-3) in PM.