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

“…These four compounds are the basis for current THM regulatory limits, most commonly reported as the total trihalomethane (TTHM) concentration [7], which is the sum of the concentration of the above mentioned compounds [8]. Recently however, there has been a surge in interest in other THMs, such as iodinated and brominated compounds, increasing the number of potential THMs observed [9,10]. …”

Section: Introductionmentioning

confidence: 99%

A New Method for the Fast Analysis of Trihalomethanes in Tap and Recycled Waters Using Headspace Gas Chromatography with Micro-Electron Capture Detection

Alexandrou

Meehan

Morrison

et al. 2017

IJERPH

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Chemical disinfection of water supplies brings significant public health benefits by reducing microbial contamination. The process can however, result in the formation of toxic compounds through interactions between disinfectants and organic material in the source water. These new compounds are termed disinfection by-products (DBPs). The most common are the trihalomethanes (THMs) such as trichloromethane (chloroform), dichlorobromomethane, chlorodibromomethane and tribromomethane (bromoform); these are commonly reported as a single value for total trihalomethanes (TTHMs). Analysis of DBPs is commonly performed via time- and solvent-intensive sample preparation techniques such as liquid–liquid and solid phase extraction. In this study, a method using headspace gas chromatography with micro-electron capture detection was developed and applied for the analysis of THMs in drinking and recycled waters from across Melbourne (Victoria, Australia). The method allowed almost complete removal of the sample preparation step whilst maintaining trace level detection limits (>1 ppb). All drinking water samples had TTHM concentrations below the Australian regulatory limit of 250 µg/L but some were above the U.S. EPA limit of 60 µg/L. The highest TTHM concentration was 67.2 µg/L and lowest 22.9 µg/L. For recycled water, samples taken directly from treatment plants held significantly higher concentrations (153.2 µg/L TTHM) compared to samples from final use locations (4.9–9.3 µg/L).

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“…However, for all methods the R 2 obtained using a 10-min (8 min extraction and 2 min desorption) period were satisfactory for quantitation at occurring levels and were similar to those obtained by EPA501.3 method [15]. The LOD and limit of quantitation (LOQ) were calculated from the S/N, where LOD = 3ˆS/N, using a 10 µg/L standards [16]. The LODs vary for individual THMs and methods but generally fall within a 2.6-5.1 µg¨L´1, which are low enough to detect THMs in natural water samples, ( Table 1).…”

Section: Methods Validationmentioning

confidence: 63%

“…The literature has shown that use of solid phase microextraction (SPME) technique affords the possibility of sampling THM analytes by either method (spot [16][17][18] and TWA [19][20][21]) with easy incorporation to subsequent GC/MS analysis. Work by Stack [22] and Valencia [23] have shown the utility of headspace-(HS-) SPME with GC/MS for measurement of THMs from swimming pools and chlorinated drinking waters.…”

Section: Introductionmentioning

confidence: 99%

Comparison of Spot and Time Weighted Averaging (TWA) Sampling with SPME-GC/MS Methods for Trihalomethane (THM) Analysis

2016

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Water samples were collected and analyzed for conductivity, pH, temperature and trihalomethanes (THMs) during the fall of 2014 at two monitored municipal drinking water source ponds. Both spot (or grab) and time weighted average (TWA) sampling methods were assessed over the same two day sampling time period. For spot sampling, replicate samples were taken at each site and analyzed within 12 h of sampling by both Headspace (HS)-and direct (DI)-solid phase microextraction (SPME) sampling/extraction methods followed by Gas Chromatography/Mass Spectrometry (GC/MS). For TWA, a two day passive on-site TWA sampling was carried out at the same sampling points in the ponds. All SPME sampling methods undertaken used a 65-µm PDMS/DVB SPME fiber, which was found optimal for THM sampling. Sampling conditions were optimized in the laboratory using calibration standards of chloroform, bromoform, bromodichloromethane, dibromochloromethane, 1,2-dibromoethane and 1,2-dichloroethane, prepared in aqueous solutions from analytical grade samples. Calibration curves for all methods with R 2 values ranging from 0.985-0.998 (N = 5) over the quantitation linear range of 3-800 ppb were achieved. The different sampling methods were compared for quantification of the water samples, and results showed that DI-and TWA-sampling methods gave better data and analytical metrics. Addition of 10% wt./vol. of (NH 4) 2 SO 4 salt to the sampling vial was found to aid extraction of THMs by increasing GC peaks areas by about 10%, which resulted in lower detection limits for all techniques studied. However, for on-site TWA analysis of THMs in natural waters, the calibration standard(s) ionic strength conditions, must be carefully matched to natural water conditions to properly quantitate THM concentrations. The data obtained from the TWA method may better reflect actual natural water conditions.

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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

Cited by 44 publications

References 28 publications

Application of hollow fiber liquid phase microextraction for simultaneous determination of regulated and emerging iodinated trihalomethanes in drinking water

Application of hollow fiber liquid phase microextraction for simultaneous determination of regulated and emerging iodinated trihalomethanes in drinking water

A New Method for the Fast Analysis of Trihalomethanes in Tap and Recycled Waters Using Headspace Gas Chromatography with Micro-Electron Capture Detection

Comparison of Spot and Time Weighted Averaging (TWA) Sampling with SPME-GC/MS Methods for Trihalomethane (THM) Analysis

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