Quantification of cytostatic platinum compounds in wastewater by inductively coupled plasma mass spectrometry after ion exchange extraction

Abstract

Cytostatic platinum compounds (CPCs) are pharmaceutical compounds widely used in chemotherapy. However, these compounds have important side effects and can be toxic to the biota once they are excreted by patients and reach the aquatic medium, even at low concentrations. Most of the works have focused on the determination of CPCs in hospital wastewaters using inductively coupled plasma mass spectrometry (ICP–MS). However, the determination of CPCs in samples from wastewater treatment plants (WWTPs) is very limited, probably due to the difficulty of extracting such hydrophilic compounds from these complex aqueous matrices. This paper presents a new optimised and developed method for the extraction and preconcentration of CPCs in wastewater samples based on ion exchange solid phase extraction and their determination by ICP–MS. Under the optimal conditions, the procedure has good reproducibility and repeatability (with deviations lower than 15%), with a relative recovery between 47 and 90% and a low matrix effect (lower than 24%). We have obtained the lowest limit of quantification achieved up until now (0.74 ng L−1), thus allowing the determination of CPCs in new matrices. The described method was used for the determination of CPCs in wastewater from a WWTP and hospital wastewater of Gran Canaria Island (Spain). We have detected concentrations between 81.94 and 13,913 ng L−1 in hospital effluents and between 3.97 and 75.79 ng L−1 in wastewater treatment plants.