*2.6. Calculations and Statistical Analysis*

Analysis of variance (ANOVA) at 95% confidence level was used to assess the significance of the difference in PhAC concentrations between the different locations. All statistical analyses were performed using the ANOVA adds-in package coupled to Excel 2016 (Microsoft Office, Microsoft, USA).

#### **3. Results and Discussion**

#### *3.1. General Quality of Wastewater and Water Resources within Zarqa River Basin*

The influent to Assamra WWTP contained 1550 mg L−<sup>1</sup> of TS, of which 33.5% was in suspended form, i.e., as TSS (Table S3 in SI). Organic matter content (expressed as COD) was high in influent samples (950 mg L−1). Comparison of influent and effluent concentrations indicated that Assamra WWTP was efficient in TSS and COD removal (98% and 96%). At all sampling locations, along with ZR, the TSS concentrations were low (<2–40 mg L<sup>−</sup>1) (Table S3), while the TS concentrations were high (840–4600 mg L−1). Jerash stream contained the highest TS concentration (4600 mg L<sup>−</sup>1) and had visible white residue. Organic matter content in river water was low (4–30 mg L−1) at all sampling locations except Sukhna station, which seemed to have minor contamination with organic matter (110 mg COD L<sup>−</sup>1). A wastewater pumping station is located upstream of Sukhna station, and leakages of wastewater would flow downstream to Sukhna station.
