Abstract
The concentration of polycyclic aromatic hydrocarbons (PAH’s) have been measured for influent, effluent and sludge samples from five Jordanian wastewater treatment plants (WWTPs). The extraction of PAH’s from wastewater samples was done using C18 solid phase extraction cartridges; dichloromethane was used as a solvent. Extraction from sludge samples was carried out by ultrasound; purification was done by means of solid phase extraction. The PAH were analyzed by gas chromatography/mass spectrometry method. The total concentrations of PAH’s in influent samples were ranged between 1.163 and 2.866 μg/mL, in effluent samples between 0.518 and 1.635 μg/mL and in the sludge samples between 2.430 and 5.020 μg/g. Also, the toxicity equivalence concentrations for sludge samples were estimated and it was found to be within the acceptable limits. The total removal efficiencies of all studied PAHs were ranged between 28 and 71.6% depending on Chemo-physical properties of the PAHs compounds and the treatment process technology. The total estimated cancer risk of exposing to PAHs in the studied sludge samples was ranged between 3.25 × 10−5 and 7.43 × 10−5. The number of people suspected to have cancer due to the exposure to the sludge of the WWTPs in Jordan is between 33 and 74 out of million.
Acknowledgements
The authors thank Deanship for Scientific Research and University of Jordan for financing this work.
Declaration of interest
The authors declare that they have no conflict of interest.