Routine Method for the Analysis of Short‐Chain Chlorinated Paraffins in Surface Water and Wastewater

Abstract

Short‐chain chlorinated paraffins (SCCPs) are persistent compounds that are included in the list of priority substances in the field of water policy of the European Union in 2001. In this paper, a method based on liquid–liquid extraction and gas chromatography with electron capture detection (GC‐ECD) is evaluated to be proposed for the routine analysis of SCCPs in environmental water. Limits of quantification (LOQ) at ng L−1 levels that allow compliance with the maximum admissible level established in the Directive 2013/39/EU, good precision (lower than 11%) and expanded measurement uncertainties (ISO 11352) (lower than 20%) for surface and wastewater samples are obtained. The good agreement between the results found using GC‐ECD and gas chromatography coupled with negative ion chemical ionization mass spectrometry (GC‐NICI‐MS), with relative errors lower than 13%, showed that GC‐ECD is a reliable method to control the presence of SCCPs in environmental water. The method is applied to river and wastewater samples collected in the Metropolitan Area of Barcelona (Spain). SCCPs are found in all the influents of wastewater treatment plants at concentrations ranging from <0.01 (MLOQ) to 3.20 μg L−1, while in the effluents they are detected in 54% of samples at levels below 0.13 μg L−1. SCCPs are not detected at the intake of a drinking water treatment plant that supply water to Barcelona city and only sporadically in the Llobregat River.