Benzene ; analysis ; chemistry ; Benzene Derivatives ; blood ; urine ; Humans

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*

OBJECTIVETo establish a method for the determination of N-butylbenzene in the workplace atmosphere by gas chromatography.

METHODSN-butylbenzene in the workplace atmosphere was collected by activated charcoal tube, desorbed using carbon disulfide, and determined by capillary column gas chromatography.

RESULTSThe method showed a linear relationship within the range of 0∼100 µg/ml. The regression equation was y = 0.870x-0.014, with the correlation coefficient r being 0.999 9. The limit of detection was 0.32 µg/ml. The minimum detectable concentration was 0.21 mg/m³ (with sampled air volume of 1.5 L). The average spike recovery rate was 97.8%∼102.6%. The within-run precision was 3.06% and the between-run precision was 3.64%. The rate of average desorption was 99.6%. The breakthrough volume was 6.34 mg. The sampling efficiency was 100%. The samples could be stored for at least 7 days at room temperature.

CONCLUSIONAll parameters of the method meet the requirements of GBZ/T 210.4-2008 "Guide for establishing occupational health standards-Part 4 Determination methods of air chemicals in workplace" and can be applied for the determination of N-butylbenzene in workplace atmosphere.

Air ; analysis ; Air Pollutants, Occupational ; analysis ; Benzene Derivatives ; analysis ; Chromatography, Gas ; methods ; Linear Models ; Workplace

OBJECTIVETo establish the biological exposure limit values of urinary S-phenylmercapturic acid (SPMA) for assessing occupational exposure to benzene.

METHODSStudy participants were selected from 55 workers of benzene exposures below 32.5 mg/m(3). The concentration of personal exposure to benzene was measured by gas chromatography and sampled with personal sampler. The urine samples were collected at the end of work shift and individual internal exposure level was evaluated by determination of SPMA in urine by HPLC/MS method. Comparison of external and internal exposure was assessed by the relative internal exposure (RIE) index.

RESULTSThe benzene exposure level ranged from 0.71 to 32.17 mg/m(3) (geometric mean 6.98 mg/m(3), median 7.50 mg/m(3)). The urinary SPMA at the end of the work shift were significantly correlated with benzene exposure, (microg/g Cr) = -8.625 + 18.367X (mg/m(3)), r = 0.8035, (P < 0.01). According to the occupational exposure limit for benzene in China and calculation of regression equation, the expected value of urinary SPMA was 101.58 microg/g Cr. Mean level of biotransformation of per mg/m(3) benzene to urinary SPMA was 18.23 microg/g Cr and the metabolic efficiencies of benzene transformation to urinary SPMA decreased with benzene exposure increased.

CONCLUSIONBased on abroad documents and data, biological limit value for occupational exposure to benzene in China is recommended as follows: 100 microg/g Cr (47 micromol/mol Cr) for SPMA in the urine at the end of shift.

Acetylcysteine ; analogs & derivatives ; urine ; Adult ; Benzene ; adverse effects ; analysis ; Benzene Derivatives ; urine ; China ; Humans ; Middle Aged ; Occupational Exposure ; adverse effects ; analysis ; Threshold Limit Values ; Young Adult

Adult ; Benzene ; toxicity ; Chromatography, High Pressure Liquid ; Humans ; Occupational Exposure ; Reference Values ; Sorbic Acid ; analogs & derivatives ; analysis

OBJECTIVETo explore the effects of occupational ethylbenzene exposure on blood neurotransmitter levels in population.

METHODSThe exposure group consisted of 246 workers occupationally exposed to ethylbenzene and the control group was composed of 122 staffs from the offices. The basic information on ethylbenzene exposure was collected by the questionnaire. The mandelic acid (MA) and phenylglyoxylic acid (PGA) in the post-working urine were measured using the high performance liquid chromatography. The levels of gamma-aminobutyric acid (GABA), dopamine (DA) and acetylcholinesterase (AchE) activity were detected by reversed phase high performance liquid chromatography, spectrofluorometry and DTNB method, respectively. The blood biochemical indexes: alanine transaminase (ALT), aspartate aminotransferase (AST), total protein (TP), albumin (ALB), alkaline phosphatase (ALP), total bilirubin (TBIL) were examined. Also the hematologic indexes: red blood cell (RBC), white blood cell (WBC), hemoglobin (HGB) and platelet (PLT) were determined.

RESULTSThe levels of MA, PGA and MA+PGA of urine in the exposed group were significantly higher than those in the control group (P < 0.05). There were no significant differences of the biochemical indexes (AST, ALT, TP, ALB, BUN, Cr, ALP and TBIL), hematologic indexes (WBC, RBC, Hb and PLT) and serum GABA between the exposure group and the control group (P > 0.05). But the serum DA [(0.21 ± 0.011) mg/L] and AChE levels [(0.321 ± 0.066) U/L] in the exposure group were significantly lower than those in the control group [(0.25 ± 0.015) mg/L, (0.583 ± 0.125) U/L], respectively (P < 0.05).

CONCLUSIONMA and PGA in urine can serve as the biomarkers of internal exposure dose. Before the obvious changes of biochemical indexes and hematologic indexes appear, the exposure to ethylbenzene can influence the blood neurotransmitter levels in workers exposed to ethylbenzene.

Adult ; Air Pollutants, Occupational ; analysis ; Benzene Derivatives ; analysis ; Case-Control Studies ; Humans ; Male ; Neurotransmitter Agents ; blood ; Occupational Exposure ; gamma-Aminobutyric Acid ; blood

OBJECTIVES: We evaluated the health effects of exposure to BTEX (Benzene, Toluene, Ethylbenzene, m,p-Xylene, o-Xylene) in the Taean area after the Hebei Spirit oil spill. METHODS: We used a questionnaire survey to look for health effects among 80 pregnant women 2 to 3 months following the Hebei Spirit oil spill. Their BTEX exposures were estimated using the CALPUFF method. We then used a multiple logistic regression analysis to evaluate the effects of BTEX exposure on the women's health effets. RESULTS: Pregnant women who lived near the accident site reported more symptoms of eye irritation and headache than those who lived farther from the site. There was a trend of decreasing symptoms with an increase in distance from the spill site. Pregnant women exposed to higher ambient cumulative levels of Xylene were significantly more likely to report symptoms of the skin (OR 8.01 95% CI=1.74-36.76) in the first day after the accident and significantly more likely to report abdominal pain (OR 3.86 95% CI=1.02-14.59 for Ethylbenzene, OR 6.70 95% CI=1.82-24.62 for Xylene) during the 1st through 4th days following the accident. CONCLUSIONS: This study suggests that exposure to BTEX from an oil spill is correlated with an increased risk of health effects among pregnant women. This implies the need to take proper measures, including the development of a national policy for environmental health emergencies and a plan for studying the short- and long-term chronic health effects associated with such spills.
Adult ; Benzene/*adverse effects/analysis ; Benzene Derivatives/*adverse effects/analysis ; *Disasters ; *Environmental Exposure ; Environmental Pollutants/*adverse effects/analysis ; Eye Diseases/chemically induced/epidemiology ; Female ; Health Surveys ; Humans ; *Petroleum ; Pregnancy ; Questionnaires ; Respiratory Tract Diseases/chemically induced/epidemiology ; Risk Factors ; Skin Diseases/chemically induced/epidemiology ; Time Factors ; Toluene/analysis ; *Women's Health ; Xylenes/analysis

OBJECTIVETo investigate the relationship between trans, trans-muconic acid (ttMA) as benzene metabolite of occupational workers and benzene concentration in air.

METHODSA rapid and sensitive high-performance liquid chromatography was developed to determine the level of urinary ttMA. ttMA was extrated from urinary samples in liquid-liquid phase a ODS (2) (5u) column (phi 4.6 mm x 150 mm) and detected at wavelength 264 nm in a UV detector using vanillic acid as an internal standard. The mobile phase was acetaticacid/tetrahydrofuran/methanol/water (v/v, 1:2:10:87). The method was validated with 56 urine samples collected from occupationally benzene-exposed individuals.

RESULTSA correlation coefficient (r = 0.9963) was found for ttMA ranging 0.10-10.00 microg/mL. The limit of detection was 0.10 microg/mL. The recovery and reproducibility were generally over 90%. There was a positive correlation between ttMA and benzene level in air. The equation was Y = 0.859 + 0.108C (before work, r = 0.6200) or Y = 1.980 + 0.179C (after work, r = 0.7930).

CONCLUSIONThis method can be used to determine and control the level of urinary ttMA in those who are occupationally exposed to benzene.

Air Pollutants, Occupational ; urine ; Benzene ; analysis ; metabolism ; Biomarkers ; urine ; Calibration ; Chromatography, High Pressure Liquid ; methods ; Environmental Monitoring ; methods ; Humans ; Metallurgy ; Occupational Exposure ; Reproducibility of Results ; Sorbic Acid ; analogs & derivatives ; analysis