Inhaltszusammenfassung

Polycyclic aromatic hydrocarbons (PAHs) contamination in aquatic system is of concern since it may constitute a sink of these contaminants for a wetland ecosystem. We investigated pollution characteristics and ecological risks of PAHs by sampling contaminated sediments and water from the Shadegan wetland in Khuzestan province, south-west Iran. Concentrations of total PAHs in water and sediment samples varied from 42±2.3 – 136±7.5 ng/L and 10±0.5 – 317±14 µg/kg, respectively. Source apportionm...Polycyclic aromatic hydrocarbons (PAHs) contamination in aquatic system is of concern since it may constitute a sink of these contaminants for a wetland ecosystem. We investigated pollution characteristics and ecological risks of PAHs by sampling contaminated sediments and water from the Shadegan wetland in Khuzestan province, south-west Iran. Concentrations of total PAHs in water and sediment samples varied from 42±2.3 – 136±7.5 ng/L and 10±0.5 – 317±14 µg/kg, respectively. Source apportionment of PAHs by two approaches (principal component analysis-multiple linear regression (PCA-MLR) and molecular isomeric ratios of specific PAHs) indicated impact of potential anthropogenic PAH sources including oil spill and incomplete combustion, bulrush combustion, vehicular exhaust and fishing boat emissions. PAHs concentration were evaluated with sediments quality guidelines based on the effect range low values/effects range-median values (ERL/ERM) and the threshold effect levels/probable effect levels (TEL/PEL). Also, a risk quotient (RQ) was elaborated for evaluation of potential toxic effects on aquatic ecosystem. Our data showed relatively insignificant adverse impact for most individual compounds. The toxic equivalent quantity (TEQ) was also calculated to estimate PAHs toxicity. TEQ value of PAHs (1.9 µg/kg) was much lower than the safe level (600 µg/kg). The fugacity fraction approach was applied to explain the trend of the selected PAHs for sediment-water exchange, which showed that the fluxes for most priority PAHs were from water to sediment suggesting no secondary source impact.» weiterlesen» einklappen

Autoren

Klassifikation

DFG Fachgebiet:
3.44 - Mineralogie, Petrologie und Geochemie

DDC Sachgruppe:
Geowissenschaften