In realistic applications mixtures of biphenyl and PCBs would not be present in a matrix of deionized (DI) water, but in much more complex, natural water matrices. As investigated before on other examples , the performance of the presented adsorbent systems, represented by PAC3Imi+/PAC10Ph@SPIONs, was tested on biphenyl and PCB mixtures in actual river water collected from the Regnitz in Erlangen, Germany (49°35'14.2" N 10°58'51.9" E) as illustrated in Figure and). Removing about 15-16 nmol of pollutants both from DI and river water matrices with an adsorption share of about 37-38 % for PCB 14 and about 34 % for the most toxic PCB 77, the PAC3Imi+/PAC10Ph@SPIONs work just as well in this more realistic scenario. The differences in comparison to Figure are likely due to strong influences of minor concentration fluctuations in the starting solutions. The data in Figure was averaged across twice as many multiplicates. So far, all extractions were performed with the same employed mass of SPIONs to identify the role of the different functional coatings. In Figure c) the employed mass is varied for constant starting amounts of 7 nmol each of biphenyl and PCBs in mixtures. Next to the removed amounts, this time also the efficiencies are given. While with the previously tested mass of 5.0 ± 0.1 mg of PAC3Imi+/PAC10Ph@SPIONs about 16 nmol of PCBs are removed, decreasing the mass by a factor of five to 1.00 ± 0.02 mg still removes about 13 nmol overall. By increasing the mass to 15.0 ± 0.1 mg about 20 nmol are removed. Overall, the removal efficiencies of biphenyl, PCB 2 and PCB 14 can be increased by employing more SPIONs with a peak for PCB 14 of 97.6 ± 0.9 % removal using 15.0 ± 0.1 mg of PAC3Imi+/PAC10Ph@SPIONs. In contrast, the efficiency for PCB 77 remains constant for all employed masses around 80 %. It should be mentioned that the removal efficiency is found being non-linearly dependent on the employed mass, which makes extrapolation hardly possible. The values should be regarded as proof-of-concept only. . Aqueous solutions of 7 mL initially contained 7 nmol (1 µM) of each pollutant, i.e., 28 nmol in sum. In DI water the pH was neutral, while the natural value of 7.95 was maintained in river water. The employed mass of PAC3Imi+/PAC10Ph@SPIONs in b) was 5.0 ± 0.1 mg. c) Variation of the employed mass of these SPIONs for treatment of DI water spiked with equally concentrated PCB mixtures as in b) shows that more SPIONs yield higher removal efficiencies of up to 97.6 ±0.9 % as demonstrated for PCB 14. Data are represented as mean ± standard deviation.