Correction: Development of a needle trap device packed with modified PAF-6-MNPs for sampling and analysis of polycyclic aromatic compounds in air.

[This corrects the article DOI: 10.1039/D4RA01651C.].

Development of a needle trap device packed with modified PAF-6-MNPs for sampling and analysis of polycyclic aromatic compounds in air.

The aim of this study was to develop a new method for sampling and analyzing polycyclic aromatic hydrocarbons in the air. This was achieved by utilizing a needle trap device packed with a modified porous aromatic framework coated with magnetic nanoparticles (PAF-6-MNPs). The modified adsorbent underwent qualitative evaluation using Fourier-transform infrared spectroscopy and X-ray diffraction, as well as scanning and transmission electron microscopy. The optimal conditions for sampling polycyclic aromatic hydrocarbons compounds were determined using a dynamic atmosphere chamber. The method was validated by taking various samples from the standard chamber, and then analyzed under different environmental sampling conditions using a gas chromatography device. The limit of detection (LOD) and limit of quantification (LOQ) values for the analytes of interest, including naphthalene, anthracene, and pyrene, ranged from 0.0034-0.0051 and 0.010-0.015 µg L-1, respectively. Also, the repeatability and reproducibility of the method expressed as relative standard deviation, for the mentioned analyses were found to be in the range of 17.8-20.5% and 20-22.9%. The results indicated that over a 20 day storage period (with the needle trap device containing the analytes of interest kept in the refrigerator), there was no significant decrease in the amount of analytes compared to the initial amount. These findings suggest that, the needle trap packed with the proposed adsorbent offers a reliable, highly-sensitive, easy-to-use, and cost-effective method for sampling polycyclic aromatic hydrocarbons in the air compared to the conventional method recommended by the National Institute of Occupational Safety and Health (NIOSH), method 5515.

Application of Fe3O4@TbBd nanobeads in microextraction by packed sorbent (MEPS) for determination of BTEXs biomarkers by HPLC-UV in urine samples.

A relatively new adsorbent based on covalent organic frameworks (COFs) was employed for the first time to extract and determine Trans, trans-muconic acid (tt-MA), Mandelic acid (MA), Hippuric acid (HA), and 3-Methylhippuric acid (m-MHA) in urine. For this purpose, microextraction was performed using the packed sorbent (MEPS) method. Following the extraction process, the prepared samples were specified via the high-performance liquid chromatography-ultraviolet detector system. The precipitation polymerization was applied to synthesize the Fe3O4@TbBd nanobeads, and the morphological and dimensional structures of the products were specified with FE-SEM images. Some key variables affecting the extraction efficiency (i.e., sample volume, elution volume, condition and washing solvents, type and volume of elution solvent, extraction cycles, temperature, and pH of the sample solution) were investigated. In ideal conditions, the limit of detection (LOD) was obtained from 0.02 µg/ml for tt-MA to 0.5 µg/ml for MA. Calibration curves (at five-point) were plotted in the range 0.05-5 µg/ml for tt-MA to 1-300 µg/ml for MA (R2 > 0.98). Moreover, intra- and inter-day precision values were 3.1-5.5 and 4.6-9.8%, respectively. The developed method was successfully employed to determine four analytes in three concentrations (low, medium, and high QCs). The results showed a satisfactory recovery (70-87%). COF-MEPS technique is a rapid, easy, user-friendly, and environment-friendly method for separating the minimum values of all BTEXs chief biomarkers from urine samples without using complicated processes and only with one adsorbent. Also, it can be a good alternative for biomonitoring the workers exposed to BTEX compounds in occupational and environmental access.

Pesticide residues levels as hematological biomarkers-a case study, blood serum of greenhouse workers in the city of Hamadan, Iran.

The cultivation of greenhouse crops is the most severe form of crop production in Iran, and vast quantities of unreasonable pesticides are being utilized to control the pests. The residual level of blood pesticides and their correlation with multibiomarkers were determined to evaluate the adverse health consequences on greenhouse workers in the Hamadan, west of Iran. Participants were 180 adult males, including 90 greenhouse workers exposed to pesticides and 90 control individuals. Blood samples were taken from all subjects for pesticide residues analysis, and hematological and biochemical parameters. The blood pesticide residues were analyzed using gas chromatography (GC) with a flame ionization detector. Hematological and biochemical parameters were determined using hematology cell counter and auto analyze, respectively. Statistical analyses were done with STATA version 14.2 software. The multivariate regression was used for relationship between various pesticide concentrations in blood and changes in biomarkers in pesticide exposed group. The analyses revealed that 64 out of the 90 workers had residues of dichlorvos, diazinon, and chlorpyrifos in their blood serum, and 56.25% out of these workers were exposed for >15-year period. The residues of all three pesticides were higher than the no observable adverse effect level (NOAEL) in all the exposure duration categories. Comparisons of hematological parameters showed that mean monocyte (0.76±0.41, P < 0.001), lymphocyte (3.52±1.20, P < 0.001) and platelet counts (278.18±66.05, P=0.001), mean platelet volume (10.18±0.59, P=0.002), and plateletcrit (PCT) (0.275±0.05, P<0.001) were significantly higher in workers than the controls, whereas hemoglobin (HB) (14.61±1.28, P=0.028), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentrations (MCHC) (32.44±0.90, P<0.001) were lower in workers than controls. These results indicate that the exposed individuals have experienced significant hemotoxic effects during the pesticide exposure. The study also predicts the risk to exposed individuals in developing countries like Iran and demands realization of safety measures to prevent such dangerous effects of pesticide exposures.

Comparing formaldehyde risk assessment in histopathology laboratory staff using three methods based on US EPA approaches in the west of Iran.

Objective. In different studies, various models have been used for exposure risk assessment of formaldehyde, so this study was conducted to compare existing methods. Method. This cross-sectional analytical study was performed in the pathology section of four hospitals in the west of Iran in 2016. Personal air sampling was performed using National Institute for Occupational Safety and Health (NIOSH) method 3500. Risk assessment with existing methods and comparison between them was performed with the statistical tests. Results. 71% of participants were exposed to values above the threshold limit value. The carcinogenic risk obtained for the staff of the studied hospitals ranged from 3 × 10-6 to 3.07 × 10-4. The potential dose of exposure to formaldehyde varied from 73.22 to 3216.06 µg · day-1. The hazard quotient value was more than 1 in 71.4% of cases. Conclusion. The results of the existing methods for carcinogenic risk assessment are almost similar. In general, the Risk Assessment Information System (RAIS) is recommended because of its simplicity and reduction of error probability, saving time and cost. The results of this study can be used as a guide to select the appropriate risk assessment method for planning, providing appropriate control measures and risk management.

Characteristics and health effects of potentially pathogenic bacterial aerosols from a municipal solid waste landfill site in Hamadan, Iran.

The aim of this study was to evaluate the potential pathogenic bacterial aerosols produced from the municipal solid waste landfill site and its health risk assessment in the Hamadan city at west of Iran. In this study, air samples were collected every month during spring and summer at six locations including the active zone, leachate collection pond, infectious waste landfill, upwind, closure landfill, and downwind using the Andersen impactor. Spatial and seasonal variations of the potential pathogenic bacterial aerosols were detected. Also, Health risk associated were estimated based on the average daily dose rates (ADD) of exposure by inhalation. The mean concentration of potentially pathogenic bacterial aerosols were 468.7 ± 140 CFU m- 3 1108.5 ± 136.9 CFU m- 3 detected in the active zone in spring and summer, respectively. Also, there was a significant relationship between meteorological parameters and bacterial concentration (p < 0.05). The predominant potential pathogenic bacterial identified in the spring were Proteus mirabilis, Streptococcus sp., and Pseudomonas sp., while in summer were Pseudomonas sp., Staphylococcus aureus, and Escherichia coli. The hazard quotient (HQ) in both seasons were less of 1. Bacteria were spread throughout the landfill space, but their maximum density was observed around the active zone and leachate collection pond. This study highlights the importance of exposure to potential pathogenic bacterial aerosols in the summer and its adverse effects, especially in the MSW landfill site active zone. Finally, controlled exposure can reduce the health hazard caused by the potential pathogenic bacterial aerosols.

A review of new adsorbents for separation of BTEX biomarkers.

The biomarker analysis of benzene, toluene, ethylbenzene and xylene (BTEXs) in biological samples is the primary technique for evaluating these compounds in occupational and environmental exposures. The BTEX biomarkers are widely used to study the BTEX distribution in the environment and workplaces. Liquid-liquid extraction and solid-phase liquid extraction are among the most commonly used conventional methods to analyze biological indices of BTEXs. New methods have been proposed to analyze BTEX biomarkers using novel adsorbents such as sol-gel composite nanotubes, molecularly imprinted polymers and metal-organic frameworks, which are based on the application of needle trap devices, microextraction by packed sorbent, and solid-phase microextraction techniques. This paper provides an overview of new methods since 2015 regarding applying microextraction methods based on new adsorbents and analyzing BTEX biomarker compounds for occupational and environmental exposures. The results were compared with the liquid-phase microextraction methods recommended for urinary BTEX biomarkers.

Design, Implementation, and Evaluation of Industrial Ventilation Systems and Filtration for Silica Dust Emissions from a Mineral Processing Company.

OBJECTIVE: Silicosis as an incurable occupational disease is common in industries and processes that contain silica dust. Since engineering controls can reduce the risk of silicosis, the goal of this study was to design, implement and evaluate industrial ventilation systems and filtration for silica dust, which is emitted from hydrocone crusher and screener units in a mineral processing company. METHODS: In this project, local exhaust ventilation (LEV) system was designed and installed using the standard and valid guidelines. The dust concentration was measured in two stages before and after installation of the ventilation system in the workplace, silica emission sources and also in the workers' inhalation area. Finally, the efficiency of the system was determined. RESULTS: The efficiency of LEV system in reducing workplace dust concentration and dust emission sources was 79.8% and 84.92% respectively. Furthermore, the efficiency of system in reducing the Respirable Crystalline Silica (RCS) at the worker's inhalation area was 92.13%. The collection efficiency of filtration system for total particles was 99.67 %. CONCLUSION: The results indicate that with designation and installation of the local exhaust ventilation (LEV) system and also installation of bag filter to collect dust, the concentration of dust in the workplace and in the inhalation area of workers has decreased significantly. As a result, this system can be used to control dust in similar industries.

A needle trap device packed with MIL-100(Fe) metal organic frameworks for efficient headspace sampling and analysis of urinary BTEXs.

The aim of this study was to develop a new method for the determination of benzene, toluene, ethylbenzene and xylene isomers (BTEXs) in urine samples. In this method, MIL-100(Fe)@Fe3 O4 @SiO2 metal-organic framework was synthesized, characterized and packed inside a needle trap device (NTD) as a sorbent for headspace extraction of unmetabolized BTEXs from urine samples followed by gas chromatography (GC) analysis. The GC device was equipped with a flame ionization detector (FID). The results showed that the optimal extraction time, extraction temperature and salt content were 60 min, 30°C and 5%, respectively. Also, the optimal desorption time and temperature were determined to be 1 min and 250°C, respectively. The limits of detection and quantification of the analytes of interest were in the ranges 0.0001-0.0005 and 0.0003-0.0014 µg ml-1 , respectively. The intra- and inter-day repeatability were <7.6%. The accuracy of the measurements in urine samples was in the range 7.1-11.4%. The results also demonstrated that the proposed NTD offered various advantages such as having high sensitivity and being inexpensive, reusable, user friendly, environmentally friendly and compatible for use with the GC device. Therefore, it can be efficiently used as a MIL-NTD for the extraction and analysis of unmetabolized BTEXs from urine samples.

Development of a needle trap device packed with titanium-based metal-organic framework sorbent for extraction of phenolic derivatives in air.

We developed a novel method of needle trap device packed with titanium-based metal-organic framework for the extraction of phenolic derivatives in air followed by gas chromatography-flame ionization detector analysis. The synthetized adsorbent was packed inside a 22-gauge spinal needle. This method was first tested at laboratory scale, and then was used for field sampling of phenolic derivatives in air. A glass chamber placed on a heater at 60°C was used to provide different concentrations of phenolic derivatives. The desorption conditions and breakthrough volume were optimized using response surface methodology. The limit of detection and limit of quantitation of the proposed method were estimated to be in the range of 0.001-0.12 and 0.003-0.62 ng/mL, respectively, indicating a high sensitivity for the suggested sampler. Storing the packed needle trap device in a refrigerator at 4˚C for 60 days did not dramatically affect the storage stability. Our findings indicated that there was a high correlation coefficient (R2  = 0.99) between the measurement results of this method and the NIOSH recommended method (XAD-7 sorbent tube). Therefore, it can be concluded that the needle trap device packed with titanium-based metal-organic framework can be used as a efficient method for extraction of phenolic derivatives in air.

Determination of urinary methylhippuric acids using MIL-53-NH2 (Al) metal-organic framework in microextraction by packed sorbent followed by HPLC-UV analysis.

For the analysis of methylhippuric acids (MHAs) in human urine samples, in this study, a new method based on the metal-organic framework (MOF) of MIL-53-NH2 (Al) in microextraction by packed sorbent (MEPS) was developed. The synthesis of MIL-53-NH2 (Al) was characterized by Fourier transform infrared spectra, field emission-scanning electron microscopy and X-ray diffraction. Response surface methodology was used to investigate the influences of several parameters including type and volume of elution, type of conditional solvent, sample volume and extraction cycle on MEPS efficiency. The results showed good recoveries (>94%) and excellent extraction efficiencies (>96%) at three different concentrations of 50, 500 and 1500 µg ml-1 (as low, mid and high concentrations, respectively) of MHA isomers. Calibration curves of MHAs were linear over the concentration range of 1-1500 µg ml-1 , with high correlation coefficients (r ≥ 0.998). The reproducibility of the proposed MIL-53-MEPS for determination of three isomers of MHA was found to be in the range of 3.5-11.1%. After optimization of the proposed technique, it was used to analyze MHAs in urine samples of workers exposed to xylenes in a petrochemical plant in Asalouyah, Iran. The results indicated that the MOF-MEPS method was selective, sensitive, rapid and efficient for the extraction of urinary MHAs. The technique is also environmentally friendly and inexpensive, and the MOF sorbent is reusable.

Development of Membrane Hollow Fiber for Determination of Maleic Anhydride in Ambient Air as a Field Sampler.

This research develops a rapid method for sampling and analysis of maleic anhydride (MA) in air using a one-step hollow fiber (HF) membrane in the liquid phase followed by high-performance liquid chromatography. A sampling chamber was prepared for sampling of MA with HF-supported de-ionized water absorbency. Several important parameters, such as sampling flow rate, sampling time, and breakthrough volume (BTV), were optimized at different concentrations using a central composite design. The results showed that sampling could be performed at the maximum period of 4 h with a flow rate of 1 mL min-1 for different concentrations (in the range of 0.05-2 mg m-3). The BTV was 240 mL. The relative standard deviations for the repeatability of interday and intraday were 7-10%, 10%, respectively, and the pooled standard deviation was 0.088. The limit of detection and limit of quantitation values were 0.033 and 0.060 mg m-3, respectively. Moreover, our findings revealed that the samples could be stored in sealed HF flexible plastic tubes in a cover at refrigerator temperature (4°C) for up to 7 days. The HF method was compared with method number 3512 National Institute Occupational Safety and Health for determination of MA. There was a good correlation (R2 = 0.99) between the two methods at a concentration of 0.05 to 2 mg m-3 in the laboratory and the average concentration of MA for both methods was 0.11 mg m-3 in the ambient air at an adhesive manufacturer. Our findings indicated that the proposed HF can act as a reliable, rapid, and effective approach for sampling of MA in workplaces.

Application of a needle trap device packed with XAD-2 polyaniline composite for sampling naphthalene and phenanthrene in air.

The purpose of this study was to develop a new method for the sampling and analysis of naphthalene (Nap) and phenanthrene (Phe) in air. XAD-2 sorbent was prepared with polyaniline (PANI) to increase its adsorption area. Thus, 22-gauge needles were packed with XAD-2/PANI sorbent for the extraction of Nap and Phe, and sampling of the analytes of interest. The compounds were dynamically sampled from the headspace of the flask in laboratory and then analyzed using a gas chromatography (GC) device equipped with flame ionization detector (FID). The needle trap device (NTD) with the proposed sorbent was more sensitive and accurate than the NIOSH 5515 method. The results showed that the optimal temperature and time for the desorption of the analytes were 350 °C and 8 min, respectively. The analytical parameters such as carryover effect, breakthrough volume, and storage time were examined. The repeatability of the method was determined to be 9.4-13.5% for Nap and 7.1-15.7% for Phe. The limits of detection (LOD) for the analytes were in the range 0.002 - 0.09 ng L-1, and the limits of quantitation (LOQ) were in the range 0.01- 0.23 ng L-1. It was also found that the NTD packed with XAD-2/PANI sorbent was a sensitive and cost-effective method, and offered a high accuracy for the sampling and analysis of PAHs in air.

Facile and sensitive determination of urinary mandelic acid by combination of metal organic frameworks with microextraction by packed sorbents.

In this study, two hybrid metal organic frameworks including MOF-5@ Fe3O4-NH2 and MOF-5@ SBA-15 for the first time were synthetized and combined with microextraction by packed sorbent (MEPS) to extract of mandelic acid (MA) from urine samples. The synthetized sorbents were characterized using FE-SEM, XRD and FT-IR techniques. The important parameters in MEPS procedure including sample volume, extraction draw_discard cycles, elution solvent volume and desorption draw-eject cycles were optimized using response surface methodology (RSM) with central composite design (CCD). The results indicated that the volume of elution solvent was the most important parameter in the recovery of MA by MOF-MEPS procedure. The optimized MOF-MEPS method offered an acceptable efficiency for the recovery of MA from urine samples (MOF-5@Fe3O4-NH2 and MOF-5@SBA-15: 94.5% and 90.3%, respectively, RSD < 3.54%). The limit of detection (LOD) of MA calculated by MOF-MEPS procedure combined with high performance liquid chromatography for MOF-5@ Fe3O4-NH2 and MOF-5@ SBA-15 were calculated to be 0.10 and 0.13 µg mL-1, respectively. The linearity dynamic ranges (LDRs) determination of urinary MA by MOF-5@ Fe3O4-NH2 and MOF-5@ SBA-15 were 0.2-100 and 0.2-90 µg mL-1, respectively. The results of the present study implied that the proposed technique is a fast and sensitive procedure for extraction and determination of MA from urine samples.

Preparation of Carbotrap/silica composite for needle trap field sampling of halogenated volatile organic compounds followed by gas chromatography/mass spectrometry determination.

BACKGROUND: A needle trap device (NTD) was packed with Carbotrap/silica composite sorbent and applied for field sampling of halogenated volatile organic compounds (HVOCs) followed by gas chromatography/mass spectrometry (GC/MS) separation and determination. METHODS: Carbotrap B, as a highly pure surface sorbent, was prepared using sol-gel method to improve its surface properties for adsorption/desorption of the target analytes. The effects of important experimental variables on the sampling and determination of trichloroethylene (thrCE) and tetrachloroethylene (tetCE) using the proposed NTD-GC/MS strategy were evaluated and optimized. RESULTS: The results showed that sampling temperature and relative humidity interfered with sampling efficiency of the developed method and peak area responses of the analytes decreased with increasing temperature and relative humidity. The peak areas of the analytes increased with raising desorption temperature from 180 to 250 °C, and increasing desorption time from 1 to 3 min. The carryover experiments showed that the carryover effect disappeared after 3 min of desorption time. The Limits of Detection (LODs) and Limits of Quantitation (LOQs) of the analytes were in the range 0.01-0.03 and 0.05-0.09, respectively. CONCLUSIONS: The results indicated that the developed NTD-GC/MS procedure can be used as a technology with high sensitivity for the field sampling and determination of HVOCs.

Evaluation of a novel hollow fiber membrane technique for collection of 1,1-dimethylhydrazine in air.

The purpose of this study was to develop a novel one-step method for the time-weighted average determination of 1,1-dimethylhydrazine (UDMH) in the air followed by spectrophotometric detection. For this reason, 0.1% hydrochloric acid as the absorbent was used in hollow fiber (HF) membrane for sampling of UDMH from an atmospheric standard chamber. Response surface methodology (RSM) with central composite design (CCD) was used to optimize the sampling parameters, such as flow rate and sampling time. Moreover, several analytical parameters including breakthrough (BT) volume, storage time, and carryover effect of the proposed HF were investigated. The results showed that optimal sampling rate was 9.90 mL/min. In order to validate the proposed method, it was compared with the National Institute for Occupational Safety and Health (NIOSH) 3515 method, which showed good compatibility between the two methods. Intra- and inter-day repeatability values of the HF method were in the range 0.082-0.1 and 0.091-0.12, respectively, and the limits of detection (LODs) and limits of quantitation (LOQs) were 0.002 and 0.006 ng/mL, respectively. The storage time of the proposed HF was 7 days at 2 °C. These results demonstrated that the one-step HF membrane offered a high sensitivity for sampling of UDMH in air.

Correction to: Selective determination of mandelic acid in urine using molecularly imprinted polymer in microextraction by packed sorbent.

In the original publication of the article, there is an error in Fig. 2c. The authors would like to correct this error and the corrected version of Fig. 2c is as follow.

Selective determination of mandelic acid in urine using molecularly imprinted polymer in microextraction by packed sorbent.

Mandelic acid (MA) is a major metabolite of ethylbenzene and styrene. For the first time, a selective, fast, and easy-to-use procedure was developed for the determination of MA in urine samples. The new procedure is based on MIMEPS, the combination of a molecularly imprinted polymer (MIP) and microextraction by packed sorbent (MEPS). High-performance liquid chromatography with ultraviolet detection (HPLC-UV) was used for the separation and determination of MA. The bulk polymerization method was used to synthesize the MIP, and the MIP and non-imprinted polymer (NIP) were characterized by Fourier transform infrared spectroscopy. The selectivity of the MIP was investigated in the presence of interferents. In addition, we investigated the various parameters that affect the performance of the MEPS, including the pH of the sample, the number of extraction cycles, sample volume, and the types and volumes of the washing and elution solvents. A six-point calibration curve was obtained in the range of 0.2-20 µg/mL (R 2 = 0.9994). The extraction recovery was more than 88.8%. The limit of detection and the limit of quantitation were 0.06 and 0.2 µg/mL, respectively. The intra- and inter-day precisions were in the range of 3.6-4.7% and 3.8-5.1%, respectively. The accuracy was -8.4 to -11.1%. The optimized procedure was selective, sensitive, and rapid, and it was both user friendly and environmentally friendly. The sample preparation process took only about 5 min, so the MIMEPS-HPLC-UV procedure is recommended as an alternative for the biomonitoring of workers exposed to ethylbenzene and/or styrene.

Ion-pair-based hollow-fiber liquid-phase microextraction combined with high-performance liquid chromatography for the simultaneous determination of urinary benzene, toluene, and styrene metabolites.

In the current study, a novel technique for extraction and determination of trans,trans-muconic acid, hippuric acid, and mandelic acid was developed by means of ion-pair-based hollow fiber liquid-phase microextraction in the three-phase mode. Important factors affecting the extraction efficiency of the method were investigated and optimized. These metabolites were extracted from 10 mL of the source phase into a supported liquid membrane containing 1-octanol and 10% w/v of Aliquat 336 as the ionic carrier followed by high-performance liquid chromatography analysis. The organic phase immobilized in the pores of a hollow fiber was back-extracted into 24 µL of a solution containing 3.0 mol/L sodium chloride placed inside the lumen of the fiber. A very high preconcentration of 212- to 440-fold, limit of detection of 0.1-7 µg/L, and relative recovery of 87-95% were obtained under the optimized conditions of this method. The relative standard deviation values for within-day and between-day precisions were calculated at 2.9-8.5 and 4.3-11.2%, respectively. The method was successfully applied to urine samples from volunteers at different work environments. The results demonstrated that the method can be used as a sensitive and effective technique for the determination of the metabolites in urine.

Effect of TiO2/GAC and water vapor on chloroform decomposition in a hybrid plasma-catalytic system.

This paper presents the combination of TiO2/GAC catalyst and NTP for the decomposition of chloroform using a DBD reactor. The experiments were performed using an AC transformer as the power supply system to determine the optimal conditions of the chloroform conversion in the presence of a hydrogen-rich substance, that is, water vapor. TiO2/GAC enhanced the removal efficiency and also CO2 selectivity significantly, leading to an acceptable conversion rate at SIEs higher than 400 J L-1. The adsorption property of GAC was noticed to be an effective factor for catalytic activity by increasing the residence time, although the higher retention time prevented the accurate determination of chlorine and carbon balance. Selectivity toward HCl was improved considerably from 24.3% to 64.3% over catalyst when water was fed as a hydrogen-rich compound. At the same time, the harmful chlorinated by-products such as TCBA and TCE declined significantly. A noticeable enhancement in the selectivity toward CO2 was observed when both catalyst and water were introduced, regardless of the inlet concentration. Our findings suggest that the hybrid of NTP with TiO2/GAC will highly be effective in the abatement of chloroform, and the addition of H2O will successfully decline harmful chlorinated by-products.