Biphenyl and PCBs were dissolved in acetone at concentrations of 100 µM followed by dilution with DI water to obtain 1 µM solutions in DI water with 1 vol% of acetone (this ensures solubility especially for the low-soluble PCB 77). These were titrated to pH 7 with aqueous 0.25 M NaOH and HCl solutions. Respectively, 7 mL of contaminant solution were given to 5.0 ± 0.1 mg (except when the mass was varied) of SPIONs, which were predispersed in 50 µL of acetone. These dispersions were put in a vortex mixer for 10 min at 500 rpm followed by 30 min of magnetic separation of the SPIONs carrying the contaminants. For the competitive extraction of biphenyl and the PCBs equal volumes each of 400 µM solutions in acetone were mixed. The resulting solution containing each contaminant at 100 µM was diluted accordingly with DI water to obtain an aqueous solution with 1 vol% of acetone containing each molecule at 1 µM. This solution was titrated to pH 7 and treated with SPIONs as described before. For the magnetic extraction from river water, the contaminants containing acetone solution was diluted with river water instead. Here, no titration was conducted to maintain the natural pH, which was measured at 7.95. For recycling the SPIONs were magnetically separated from the hexane solution that was later quantified, washed with fresh hexane and dried in the oven at 80 °C. These particles were then wetted with 50 µL of acetone again and iteratively applied to contaminant-spiked DI water. All magnetic extractions of individual biphenyl and PCBs as well as the competitive study containing all four contaminants were conducted in hexaplicates. Comparison of DI to river water as well as the study of varying starting mass of SPIONs were done in triplicates, while recycling was done in quintuplicates but one multiplicate was lost in the last step for characterization purposes.