Environmental Monitoring ; Humans ; Occupational Exposure ; Toluene ; analysis

Objective: To establish a purge and trap-gas chromatography-mass spectrometry method based on soil analysis model for the determination of six benzene homologues (benzene, toluene, ethylbenzene, m-xylene, p-xylene and o-xylene) in human blood. Methods: From September 2020 to May 2021, diatomite was used as a dispersant to add 2.0 ml blood sample and fully mixed. The sample was directly injected into the purging and collecting bottle after purging. The gas chromatography column was used for separation. The retention time locking was used for qualitative analysis and the selected ion scanning mode (SIM) was used for detection. The detection limit and recovery rate of the method were analyzed. Results: The linear range of the method for the determination of six benzene homologues in human blood was 0.02-10.00 ng/ml, the correlation coefficient was 0.9927-0.9968, the detection limit was 0.006-0.016 ng/ml, the recovery rate of sample spiking was 84.39%-102.41%, and the precision of the method was 3.06%-6.90%. Conclusion: Purge and trap-gas chromatography-mass spectrometry can simultaneously determine the contents of six benzene homologues in human blood. The pretreatment method is simple, time-saving, and the method has low detection limit, which provides a scientific basis for the detection of benzene homologues in human body.
Humans ; Benzene/analysis* ; Gas Chromatography-Mass Spectrometry/methods* ; Xylenes/analysis* ; Benzene Derivatives/analysis* ; Toluene/analysis*

Adhesives ; chemistry ; Benzene ; analysis ; Chromatography, Gas ; Hexanes ; analysis ; Toluene ; analysis ; Trichloroethylene ; analysis

Benzene ; analysis ; Chemical Industry ; Chromatography, Gas ; methods ; Humans ; Occupational Exposure ; analysis ; Toluene ; analysis ; Trichloroethylene ; analysis ; Xylenes ; analysis

OBJECTIVETo develop a gas chromatography method for determination of residual solvents in 7-amino-3-chloro cephalosporanic acid (7-ACCA).

METHODSThe residual levels of acetone, methanol, dichloromethane, ethyl acetate, isobutanol, pyridine and toluene in 7-ACCA were measured by gas chromatography using Agilent INNOWAX capillary column (30 m × 0.32 mm,0.5 μm). The initial column temperature was 70° maintained for 6 min and then raised (10°C/min) to 160°C for 1 min. Nitrogen gas was used as carrier and FID as detector. The flow of carrier was 1.0 ml/min, the temperature of injection port and detector was 200°C and 250°C, respectively.

RESULTThe limits of detection for acetone, methanol, dichloromethane, ethyl acetate, isobutanol, pyridine, toluene in 7-ACCA were 2.5 μg/ml, 1.5 μg/ml, 15 μg/ml, 2.5 μg/ml, 2.5 μg/ml, 2.5 μg/ml and 11 μg/ml, respectively. Only acetone was detected in the sample, and was less than the limits of Ch.P.

CONCLUSIONThe method can effectively detect the residual solvents in 7-ACCA.

Acetone ; analysis ; Cephalosporins ; Chromatography, Gas ; methods ; Drug Contamination ; Methanol ; analysis ; Methylene Chloride ; analysis ; Solvents ; analysis ; Toluene ; analysis

Objective: This study was designed to conduct a retrospective and systematic occupational health risk assessment (OHRA) of enterprises that used benzene, toluene, and xylene (BTX) in Shanghai, China. Methods: All data for the study were obtained from 1,705 occupational health examination and evaluation reports from 2013 to 2017, and a semiquantitative model following Chinese OHRA guidelines (GBZ/T 298-2017) was applied for the assessment. Results: The selected enterprises using BTX were mainly involved in manufacturing of products. Using the exposure level method, health risk levels associated with exposure to BTX were classified as medium, negligible, or low. However, the risk levels associated with benzene and toluene were significantly different according to job types, with gluers and inkers exhibiting greater health risks. For the same job type, the health risk levels assessed using the comprehensive index method were higher than those using the exposure level method. Conclusion Our OHRA reveals that workers who are exposed to BTX still face excessive health risk. Additionally, the risk level varied depending on job categories and exposure to specific chemicals. Therefore, additional control measures recommended by OHRA guidelines are essential to reduce worker exposure levels.
Air Pollutants, Occupational/analysis* ; Benzene/analysis* ; China ; Humans ; Occupational Exposure/adverse effects* ; Retrospective Studies ; Risk Assessment ; Toluene/analysis* ; Xylenes/analysis*

OBJECTIVETo explore the characteristics of particulate matter pollution in coke oven plant, so as to provide scientific data for establishing occupational exposure limits for coke oven emissions.

METHODSConcentrations of CO, SO₂, BSM, BTEX (concentrations of benzene, toluene and xylene were determined in this study), PM₁₀, PM₂.₅, 16 selected PAHs in PM₁₀ and PM₂.₅ were determined in the work environment of a coke oven plant in Wuhan. The work environment was divided into the adjunct area, the bottom of, the side of and the top of coke oven.

RESULTSThe concentrations of CO, SO₂, BSM, BETX, PM₁₀, PM₂.₅, PAHs in PM₁₀ and PM₂.₅ were significantly related to working environmental categories, respectively, and were increasing as the adjunct area < bottom < side < top (P (trend) < 0.05). PM₁₀ was statistically significantly correlated with CO, SO₂, benzene, BTEX and BSM (0.705, 0.823, 0.664, 0.624 and 0.734, respectively). PM₂.₅ was statistically significantly correlated with CO, SO₂, benzene, BTEX and BSM (0.635, 0.916, 0. 680, 0.553 and 0.726, respectively). BSM was statistically significantly correlated with benzene (0.689). The ratios of PM₂.₅ to PM₁₀ between different work environments were not significantly different in one-way ANOVA (P > 0.05). The distribution of aromatic rings and the concentrations of total benzo[a] pyrene equivalents in PM₁₀ and PM₂.₅ were not statistically different between work environments.

CONCLUSIONThe concentrations of particulate matter was related with other contents of coke oven emissions in coke work environment, and the contents and types of PAHs in PM₁₀ and PM₂.₅ were similar.

Air Pollutants, Occupational ; analysis ; Benzene ; analysis ; Benzo(a)pyrene ; analysis ; Coke ; Occupational Exposure ; analysis ; Particulate Matter ; analysis ; Polycyclic Aromatic Hydrocarbons ; analysis ; Toluene ; analysis ; Workplace ; Xylenes ; analysis

Air ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography, Gas ; methods ; Environmental Monitoring ; methods ; Toluene ; analogs & derivatives ; analysis ; Workplace

OBJECTIVETo determine the contents of the residual solvents, methanol, ethanol, toluene, dichloromethane and dioxane in ranolazine raw material.

METHODSHeadspace gas chromatography was used to analyze the residual solvents quantitatively. Samples were analyzed on an HP-INNOWAX column with column temperature at 45 degrees Celsius; using water as solvent.

RESULTSFive residual solvents were completely separated. The liner range and recoveries were satisfied. RSD of precision and accuracy was less than 8% with average recoveries between 87.1% and 105.6%.

CONCLUSIONThe method could be used for the quality control of ranolazine raw material.

Acetanilides ; analysis ; Chromatography, Gas ; methods ; Drug Contamination ; prevention & control ; Enzyme Inhibitors ; analysis ; Ethanol ; analysis ; Methanol ; analysis ; Piperazines ; analysis ; Ranolazine ; Reproducibility of Results ; Solvents ; analysis ; Toluene ; analysis

OBJECTIVETo develop a method for the pretreatment of the series of HPD macroporous adsorption resin (MAR).

METHODThe effect of 2% NaOH to pretreatment of the series of HPD MAR was studied by gas chromatography and UV spectrometery.

RESULTThe eluting effect by ethanol was better after the MAR was marinated and eluted by 2% NaOH.

CONCLUSIONThe pretreatment of the series of HPD MAR was: after marinated and eluted by 2% NaOH, the series of HPD MAR were eluted by ethanol at 2 BV x h(-1) at 60 degrees C for 3-4 bed volumes (BV). At then the UV absorbance of eluate was 0.2-0.5. Benzene was not detected and the other residues less than 10 mg x L(-1) in eluted-MAR by GC. And the MARs match to the standard of medicine.

Adsorption ; Chromatography, Gas ; Drug Contamination ; Ethanol ; Naphthalenes ; analysis ; Resins, Synthetic ; chemistry ; Sodium Hydroxide ; Spectrophotometry, Ultraviolet ; Toluene ; analysis