آب و فاضلاب (Oct 2015)
Polycyclic Aromatic Hydrocarbons in Surface Sediments from the Southern Shores of the Caspian Sea, Anzali City: Toxicity Assessment and Source Identification
Abstract
The Caspian Sea has recently experienced great damages due to intense pressure from human activities, petroleum contaminant discharges from oil extraction and refining activities, and domestic and industrial wastewaters discharged into the environment. The aim of this study was to determine the sources and levels of one of the most dangerous oil pollutants ‒ polycyclic aromatic hydrocarbons ‒ in the southern shores of the Caspian Sea (Anzali City). The data would be compared with standard PAHs concentrations in order to derive the information required for designing appropriate management measures. For the purposes of this study, nine surface sediment samples were collected from the experimental field and gas chromatography with mass spectrometry (GC-MS) was used to analyze the samples for their contaminants. The total PAHs concentrations ranged from 736 to 9009 ng g-1d.w with an increasing trend along the east-west direction. Also, multiple indexes were used to detect the petrogenic origin of these compounds. Compared with sediment quality guidelines (SQGs) of Florida (TELs/PELs), the levels for half the PAH compounds exceeded TELs. Moreover, naphthalene, fluorine, and phenanthrene concentrations exceeded the PELs in some stations, indicating likely acute toxic effects. However, comparison with sediment quality guidelines (SQGs) of the United States (TELs/PELs) revealed that most of the compounds at the stations investigated were lower than ERLs. It was concluded that the quality guidelines of the Florida State are more conservative for protecting the biotic organisms in the region.
