Quantitative Determination of Phthalate Esters and Bisphenol-A Residues in Wastewater Treatment Plants Outflow in Saudi Arabia: Gas Chromatography/Mass Spectrometry-Based Analytical Study

The aquatic system is unfortunately vulnerable to contamination by chemicals as bisphenol A (BPA) and phthalate esters (PAEs) that arise from plastic products frequently used. Water supply is limited in Saudi Arabia. Therefore, many wastewater-treatment plants (WTPs) have been established for wastewater recycling in industry and agricultural purposes. The current study updated and validated the concentrations of BPA and six PAEs (dibutyl phthalate (DBP), dimethyl phthalate (DMP), diethyl phthalate (DEP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP), and dioctyl phthalate (DOP)) in wastewater samples obtained from 5 wastewater treatment plants in 3 Saudi cities. Also, the study compared the concentrations of these chemicals in the secondary WTPs versus the tertiary ones. Chromatography/mass spectrometry was used for the extraction of the chemicals in water samples. All measurements were exposed to comparison and correlation statistical analysis. Both DEHP and DBP were found in all obtained treated wastewater samples. Meanwhile, DOP, BBP, DEP, DMP, and BPA were identified in the following percent of samples, 74.1%, 80.2%, 84%, 84.1%, and 98.01% respectively. The levels of DMP (p < 0.05), DOP, (p < 0.05) and BPA (p < 0.05) were higher in tertiary-treated water sample than those secondary.