Application of automated solid-phase microextraction to determine haloacetonitriles, haloketones, and chloropicrin in Canadian drinking water

Abstract

An automated headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) method was developed to monitor the occurrence of selected haloacetonitriles (HANs), haloketones (HKs), and chloropicrin (CP) in drinking water supplies. The method was rapid with analysis time of 30 min, including extraction and chromatographic run. Chemical ionization (CI) was used to increase the sensitivity of the method for the HKs. SPME fibers with seven different coatings including commercial polyacrylate (PA), carbowax/divinylbenzene (CW/DVB), polydimethylsiloxane (PDMS), polydimethylsiloxane/divinylbenzene (PDMS/DVB), carboxen/polydimethylsiloxane (CAR/PDMS), divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS), and a novel custom-made polydimethylsiloxane/divinylbenzene-N-vinylpyrrolidone (PDMS/DVB-NVP) were evaluated. The DVB/CAR/PDMS fiber was found more suitable for the range of the analytes and the novel PDMS/DVB-NVP fiber more efficient for the brominated acetonitriles under the experimental conditions. Method detection limits (MDLs) for the chlorinated acetonitriles and CP varied between 2 and 40 ng/L and for the brominated acetonitriles and HKs between 100 and 180 ng/L. Relative standard deviations (RSD %) of measurements were 4–7%. The method was applied in parallel with a liquid–liquid extraction gas chromatography electron capture detection (LLE-GC-ECD) method (EPA Method 551.1) to the analysis of drinking water samples from eight Canadian water treatment and distribution systems. The results generated by the two methods showed good agreement.

Simultaneous and high-throughput analysis of iodo-trihalomethanes, haloacetonitriles, and halonitromethanes in drinking water using solid-phase microextraction/gas chromatography-mass spectrometry: an optimization of sample preparation

“…Method limits of detection (LODs) and quantification (LOQs) were calculated, respectively, as the concentration equivalent to S/N = 3 and S/N = 10 using 10 ng/L (for Iodo-THMs and HANs) and 100 ng/L (for HNMs) standards. LODs ranged from 6 ng/L for TCAN to 50 ng/L for DCAN and LOQs were 20 ng/L for TCAN and 165 ng/L for DCAN; these are consistent with the results obtained using the same fiber for HANs [14,16]. LODs ranged from 1 ng/L for TCNM to 50 ng/L for BCNM and LOQs were 5 ng/L for TCAN and 165 ng/L for BCNM using SPME; results were similar to or higher than those obtained by LLE [12,13].…”

“…LLE is the primary method used to extract and concentrate volatile DBPs (especially HANs and TCNM) by U.S. EPA Method 551 [11,12]. A method based on single-drop microextraction in the static headspace has been proposed to decrease the length of time required for the extraction process as well as the amount of work required; this method allows for low detection limits for the nine HNMs (0.06-1.2 g/L) [13], similar to SPME for TCNM (chloropicrin) (0.04-0.5 g/L) [14,15]. There has been limited reporting on the application of SPME for the extraction of HNMs, besides TCNM.…”

“…The most commonly used SPME fiber for the analysis of four HANs (TCAN, DCAN, DBAN, and BCAN) and one HNM (TCNM) is carboxen/polydimethylsiloxane (CAR/PDMS) [13], and for the analysis of six HANs (MCAN, MBAN, DCAN, DBAN, BCAN, and TCAN) is divinylbenzene (DVB)/CAR/PDMS [10]. The DVB/CAR/PDMS fiber was found to be more suitable for the range of analytes, and the novel PDMS/DVB-NVP fiber for brominated acetonitriles [14]. The six Iodo-THMs from drinking water were extracted using SPME and the carbowax/divinylbenzene (carbowax/DVB) fiber [16,17]; this analysis had similar precision to LLE methods for the analysis of Iodo-THMs [1,4].…”

A study of thin film solid phase microextraction methods for analysis of fluorinated benzoic acids in seawater

“…For direct thermal desorption to the MS, extractions of FBAs were performed with a PDMS loaded with DVB (5m particles) as extraction phase, which has already been approved in several studies [28,29] as a thermally stable extraction phase with a wide range of analyte coverage. Extraction experiments were performed manually in 2 mL amber glass vials sealed with PTFE caps.…”

Effervescence-assisted spiral hollow-fibre liquid-phase microextraction of trihalomethanes, halonitromethanes, haloacetonitriles, and haloketones in drinking water

“…The conventional method for HANs and HNMs determination is the US EPA Method 551, which is based on LLE and GC-ECD (Munch and Hautman, 1995;Liew et al, 2012;Huang et al, 2013) and, most recently LLE and GC-MS with a programmable temperature injector for the analysis of 25 N-DBPs (HAAs, HNMs, and HANs) in drinking water (Carter et al, 2019). Another method widely used for the determination of these compounds is extraction by SPME and the analysis by GC-ECD and/or GC-MS (Montesinos and Gallego, 2012a;Luo et al, 2014;Kermani et al, 2013), as well as single-drop microextraction (SDME) in the static headspace mode followed by GC-MS for the determination of HNMs (Montesinos et al, 2011).…”