Toluene-induced erythrodermic lichen planus

Lichen planus is an inflammatory disease that affects the skin and mucous membrane. The exact etiology is unknown, but it is considered an immunologically mediated disease toward unrecognized antigen possibly located at the basal cell layer. Many clinical variants are recognized. Lichen planus-like lesions can be seen in chronic versus host disease, drugs, and chemicals. Here, we report a new case of a male patient who was exposed to toluene-containing compounds after which he developed an erythrodermic eczematous and lichenoid eruption, which is to the best of our knowledge, the third case of toluene-induced lichen planus reported worldwide and the first case in our country.

Benzene and Toluene concentration at different Traffic intersection during pre-mid-post winter season, in ambient air of Aligarh and its impact on human health

In current scenario, pollution in environment, is a big problem for all living species at around the world. We know that, Volatile Organic Compounds (VOCs) in presence of sunlight and oxides of nitrogen in atmosphere are considered as precursors for ozone production at the layer of Troposphere. Concentration of Benzene and Toluene (BT) in ambient air was measured near three major traffic sites in the city of Aligarh, India. All air samples were collected using for two times (in a month) during eight hours of normal working period time for in October – December 2020, and January - March 2021. The three selected sites used in this study represent traffic sites ( at Etah Chungi Chauraha, Quarsi Chauraha and Sootmil Chauraha, Aligarh ). In this study, real-time measurements of Benzene and Toluene concentration were performed the programmable compound specific PID detector designed to provide instantaneous exposure monitoring of a specific organic gas. It monitors a specific gas by utilizing a gas separation tube and the photo-ionization detector (PID) with a 9.8 eV gas discharge lamp (range- 50 ppb to 200 ppb) and whole data analyzed by SPSS software. The study the higher concentration 25.32 ?g/m3 of Benzene in the evening shows at site 3 and lower concentration 10.22 ?g/m3 of Benzene shows at site 2 in the morning. The higher concentration 22.22 ?g/m3 in the evening of Toluene shows at site 1 and lower concentration 07.10 ?g/m3 in the evening of Toluene shows at site 2, were observed respectively. Benzene and Toluene were widely used as a solvent in different products and petroleum. Exposure to a mixture of toluene and benzene in air led to an increase in the cytotoxic effect and DNA damage without any further repair and also its chronic effect on human health. The higher concentration of benzene and toluene co-exposure of benzene or toluene in this study. The relevance of these data on interactions for humans exposed at low benzene concentrations can be best assessed only when the mechanism of interaction is understood at a quantitative level and incorporated within a biologically based modelling framework for human health.

Involuntary Emotional Expression Disorder in a Patient With Toluene Leukoencephalopathy / Trastorno de expresión emocional involuntaria en un paciente con leucoencefalopatía por tolueno

ABSTRACT Objective: Inhalant users may develop toluene leukoencephalopathy, a devastating neuropsychiatric disorder. We present a case of toluene-induced damage to the corticospinal and the corticonuclear tracts, which presented with involuntary emotional expression dis-order. Methods: Case study of a 20-year-old man with a 3-year history of frequent solvent abuse was admitted to the Neuropsychiatry Unit of the National Institute of Neurology and Neurosurgery because "he could not speak or walk" but would keep "laughing and crying without reason". Results: Neuropsychiatric examination revealed pathological laughter and crying, facial and speech apraxia, a bilateral pyramidal syndrome, and lack of control of urinary sphincter. Magnetic resonance imaging revealed a highly selective bilateral damage to the pyramidal system and the somatosensory pathway. SPECT imaging showed left fronto-parietal hypoperfusion. Conclusions: This document provides support for the understanding of involuntary emotional expression disorders as a differential diagnosis in the clinical practice of psychiatrists, as well as the functional anatomy of these conditions.

RESUMEN Objetivo: Los usuarios de inhalantes pueden contraer leucoencefalopatía por tolueno, un trastorno neuropsiquiátrico devastador. Se presenta un caso de daño inducido por tolueno en el tracto corticoespinal y corticonuclear, que se manifestó con un trastorno involuntario de la expresión emocional. Métodos: Un varón de 20 años con antecedente de 3 años de abuso de solventes ingresó en la Unidad de Neuropsiquiatría del Instituto Nacional de Neurología y Neurocirugía porque «no podía hablar ni caminar¼ y presentaba episodios súbitos de risa y llanto sin razón aparente. Resultados: La valoración neuropsiquiátrica reveló risa y llanto patológicos, apraxia facial y fonatoria, síndrome piramidal bilateral y ausencia de control del esfínter urinario. La resonancia magnética cerebral mostró un daño bilateral muy selectivo del sistema piramidal y la vía somatosensorial. La imagen de tomografía computarizada por emisión monofotónica mostró hipoperfusión frontoparietal izquierda. Conclusiones: Este documento proporciona apoyo para la comprensión de los trastornos de la expresión emocional involuntaria como diagnóstico diferencial en la práctica clínica de los psiquiatras, así como de la anatomía funcional de estas condiciones.

Neurotoxicidad en trabajadores petroquímicos con bajos índices de exposición a disolventes orgánicos / Neurotoxicity among petrochemical workers with low exposure indexes to organic solvents

Resumen: Objetivo: Estimar el desempeño neuropsicológico y su asociación con la exposición a disolventes orgánicos (DO) en trabajadores petroquímicos en México. Material y métodos: Estudio transversal en 203 trabajadores: 102 expuestos a DO y 101 no expuestos. Se evaluó el desempeño neuropsicológico con Neurobehavioral Core Test Battery y la exposición a DO con la medición de metabolitos de exposición para tolueno, xilenos y benceno. Resultados: Los trabajadores expuestos presentaron un peor desempeño en todas las pruebas (p<0.05), excepto en la prueba de Santa Ana. Esto se corroboró con modelos de regresión; los trabajadores expuestos a DO tuvieron un mayor número de errores y realizaron las pruebas en mayor tiempo (p<0.05), además de presentar mayores probabilidades de padecer síntomas de neurotoxicidad (OR: 2.93; IC95%: 0.96, 8.96). Conclusiones: La exposición ocupacional a disolventes orgánicos, aun a niveles permitidos por la normatividad mexicana vigente, se relacionó con un menor desempeño neuropsicológico.

Abstract: Objective: To estimate the neuropsychological performance and its association with exposure to organic solvents (OS) among petrochemical workers in Mexico. Materials and methods: Cross-sectional study including 203 workers: 102 exposed to OS and 101 non-exposed. Neuropsychological performance was evaluated with Neurobehavioral Core Test Battery. Exposure to OS was evaluated with the metabolites from exposure to toluene, xylenes and benzene. Results: Exposed workers presented with a worse performance in all tests (p<0.05), except for Santa Ana test. This was corroborated with regression models; workers exposed to OS had a higher number of mistakes and performed the tests in longer time (p<0.05), together with having greater odds of neurotoxicity symptoms (OR: 2.93; 95%CI: 0.96, 8.96). Conclusions: Occupational exposure to organic solvents, even at levels allowed by current Mexican standards, was related to an impaired neuropsychological performance.

Analyzing the prevalence of key occupational hazards in 56 printing enterprises in Shenzhen City / 中国职业医学

@# Objective To investigate the prevalence of the occupational hazard of organic solvent and noise in printing and Methods record medium production enterprises in Longgang District of Shenzhen City. A total of 56 printing and record medium production enterprises were selected as the study subjects by judgmental sampling method to analyze the worksite Results survey of occupational health and the key occupational hazard factors. There were 256 organic solvent samples ， detected in 56 enterprises which included a total of 148 terms and 1 358 categories of volatile constituents. The top three （ ）， - （ ） （ ） volatile constituents were toluene 35.5% n hexane 25.7% and methanol 23.8% . The top three detected samples of the （ ， ， ， ， - ， ，- ， eight key chemical occupational hazard factors benzene toluene xylene ethylbenzene n hexane 1 2 dichloroethane ） ， - ， trichloroethylene and chloroform were toluene n hexane and ethylbenzene. In the workplace air toluene was the most risk ， factor of occupational hazard factors in enterprise and in sample detection while no trichloromethane was detected. The toluene in workplace air was found to exceed the national standard with the rate of 2.6%. It showed that 27.9% of the work sites were found occupational noise hazard which was over national standard in the 10 key work sites. Only 64.3% and 57.1% enterprises - performed occupational hazard factors detection and occupational health examination. Both none or invalid toxicant proof - facilities accounted for 33.9% of the enterprises. Both none or invalid noise proof facilities accounted for 78.6% of the Conclusion ， - enterprises. The occupational hazards factor of toluene n hexane and noise were serious in printing and record ， medium production enterprises in Longgang District of Shenzhen City and the occupational health management was imperfect. The occupational regulation should be enhanced in this industry.

Inhibition of TAK1 aggravates airway inflammation by increasing RIPK1 activity and promoting macrophage death in a mouse model of toluene diisocyanate-induced asthma / 南方医科大学学报

OBJECTIVE@#To explore the effect of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) on toluene diisocyanate (TDI)-induced allergic airway inflammation in mice.@*METHODS@#Thirty-two mice were randomly divided into AOO group, AOO+5Z-7-Oxozeaenol group, TDI group, and TDI+5Z-7-Oxozeaenol group. Another 32 mice were randomly divided into AOO group, TDI group, TDI +5Z-7-Oxozeaenol group, and TDI +5Z-7-Oxozeaenol + Necrostatin-1 group. TAK1 inhibitor (5Z-7-Oxozeaenol, 5 mg/kg) and/or RIPK1 inhibitor (Necrostatin-1, 5 mg/kg) were used before each challenge. Airway responsiveness, airway inflammation and airway remodeling were assessed after the treatments. We also examined the effect of TDI-human serum albumin (TDI-HSA) conjugate combined with TAK1 inhibitor on the viability of mouse mononuclear macrophages (RAW264.7) using CCK8 assay. The expressions of TAK1, mitogen-activated protein kinase (MAPK) and receptor interacting serine/threonine protease 1 (RIPK1) signal pathway in the treated cells were detected with Western blotting. The effects of RIPK1 inhibitor on the viability of RAW264.7 cells and airway inflammation of the mouse models of TDI-induced asthma were evaluated.@*RESULTS@#TAK1 inhibitor aggravated TDI-induced airway inflammation, airway hyper responsiveness and airway remodeling in the mouse models (P < 0.05). Treatment with TAK1 inhibitor significantly decreased the viability of RAW264.7 cells, which was further decreased by co-treatment with TDI-HSA (P < 0.05). TAK1 inhibitor significantly decreased the level of TAK1 phosphorylation and activation of MAPK signal pathway induced by TDI-HSA (P < 0.05). Co-treatment with TAK1 inhibitor and TDI-HSA obviously increased the level of RIPK1 phosphorylation and caused persistent activation of caspase 8 (P < 0.05). RIPK1 inhibitor significantly inhibited the reduction of cell viability caused by TAK1 inhibitor and TDI-HSA (P < 0.05) and alleviated the aggravation of airway inflammation induced by TAK1 inhibitors in TDI-induced mouse models (P < 0.05).@*CONCLUSION@#Inhibition of TAK1 aggravates TDI-induced airway inflammation and hyperresponsiveness and may increase the death of macrophages by enhancing the activity of RIPK1 and causing persistent activation of caspase 8.

Occupational Health Risk Assessment of Benzene, Toluene, and Xylene in Shanghai / 生物医学与环境科学（英文）

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.

Effects of Toluene on the Development of the Inner Ear and Lateral Line Sensory System of Zebrafish / 生物医学与环境科学（英文）

Objective@#The aim of this study was to explore the ototoxicity of toluene in the early development of zebrafish embryos/larvae.@*Methods@#Zebrafish were utilized to explore the ototoxicity of toluene. Locomotion analysis, immunofluorescence, and qPCR were used to understand the phenotypes and molecular mechanisms of toluene ototoxicity.@*Results@#The results demonstrated that at 2 mmol/L, toluene induced zebrafish larvae death at 120 hours post fertilization (hpf) at a rate of 25.79% and inhibited the rate of hatching at 72 hpf. Furthermore, toluene exposure inhibited the distance travelled and average swimming velocity of zebrafish larvae while increasing the frequency of movements. As shown by fluorescence staining of hair cells, toluene inhibited the formation of lateral line neuromasts and middle line 1 (Ml @*Conclusion@#This study indicated that toluene may affect the development of both the inner ear and lateral line systems in zebrafish, while the lateral line system may be more sensitive to toluene than the inner ear.

Intoxicación por tolueno / Toluene poisoning

Resumen El ser humano está inmerso en un entorno donde inhala, ingiere o absorbe muchas sustancias químicas, de las cuales toman relevancia las exposiciones en los lugares de trabajo y las que causan la muerte en la práctica médico forense. El tolueno es un inhibidor neuronal asociado con daño progresivo del sistema nervioso central y periférico, su toxicidad puede ocurrir por inhalación involuntaria o deliberada y puede llevar incluso a la muerte. Se realizó una revisión bibliográfica en diferentes bases de datos, de los artículos publicados referentes al tema de los últimos ocho años, con el objetivo de revisar las características del químico, el metabolismo, las intoxicaciones agudas y las crónicas, así como sus implicaciones letales. Se concluye que para mejorar la pericia médico legal, al valorar casos de intoxicacion por tolueno se deben de contemplar los criterios de causalidad en los casos de enfermedad laboral y en sospecha de causa de muerte es fundamentantal el resultado toxicológico ante la ausencia de hallazgos específicos en la autopsia.

Abstract The human being is immersed in an environment where he inhales, ingests or absorbs many chemical substances, in forensic medical practice the exposures in the workplace and those that cause death take on relevance. Toluene is a neuronal inhibitor associated with progressive damage of the central and peripheral nervous system, its toxicity can occur by involuntary or deliberate inhalation and can even lead to death. A bibliographic review was carried out in different databases, of the published articles referring to the subject of the last eight years, with the objective of reviewing the characteristics of the chemical, the metabolism, both acute and chronic poisoning and its lethal implications. It is concluded that to improve the legal medical expertise when assessing cases of toluene poisoning, causality criteria must be considered in cases of occupational disease and in suspected cases of death the toxicology result is fundamental in the absence of specific findings in the autopsy.

Biomarkers of susceptibility and effect in car painters exposed to organic solvents / Biomarcadores de susceptibilidad y efecto en pintores de carros expuestos a solventes orgánicos

Abstract Introduction: Car painters are routinely exposed to organic solvents classified as carcinogenic and mutagenic substances. Objective: To characterize the population susceptibility and evaluate the genotoxic effects of exposure to organic solvents. Methods: A cross-sectional study comparing a group of car painters exposed to organic solvents with a non-exposed group. CYP2E1 polymorphisms and the presence of micronuclei in lymphocytes were determined. Results: One hundred twenty-two workers participated in the study: 62 who worked in car paint shops and were exposed to solvents, and 60 who were not exposed. There were statistically significant differences between the two groups regarding micronucleated cells and nucleoplasmic bridges frequencies (p=0.042 and p=0.046, respectively; exact likelihood ratio). Significant differences were found at the interaction between the CYP2E1 genotype c1c1 and occupational exposure to solvents, with higher frequencies of micronuclei (p= 0.013) and micronucleated cells (p= 0.015). However, when the frequencies of micronuclei, micronucleated cells and nucleoplasmic bridges in the exposure group were compared between the c1c1 and c2c2/c1c2 allele groups of the CYP2E1 polymorphism, statistically significant differences were found. Conclusions: This study confirms that when workers with CYP2E1 polymorphisms, specifically the c1c1 genotype, are exposed to organic solvents, they are more likely to have somatic cell mutations, a condition associated with increased susceptibility to diseases such as cancer

Resumen Introducción: Los pintores de vehículos automotores están rutinariamente expuestos a agentes como los solventes orgánicos, capaces de producir efectos mutágenos y carcinógenos. Objetivo: Caracterizar la susceptibilidad poblacional y evaluar los efectos genotóxicos debidos a la exposición a solventes orgánicos. Métodos: Estudio de corte transversal que comparó a un grupo de pintores de carros expuestos a solven tes orgánicos con un grupo de personas no expuestas. Fueron determinados tanto los polimorfismos de CYP2E1 como la presencia de micronúcleos en linfocitos. Resultados: Participaron 122 personas, 62 trabajadores de talleres de pintura de autos expuestos a solventes y 60 personas no expuestas. Con relación al cuestionario Q 16, 32% de los expuestos refirieron síntomas sugestivos de neurotoxicidad. Las frecuencias de células micronucleadas y de puentes nucleoplásmicos fueron significativamente mayores en los expuestos que en los no expuestos: p= 0.042 y p= 0.046, respectivamente, Razón de verosimilitud exacta). Fueron halladas diferencias significativas en la interacción de CYP2E1 (c1c1) y la exposición ocupacional a solventes, con mayores frecuencias de micronúcleos (p= 0.013) y de células micronucleadas (p= 0.015). Conclusiones: Este estudio reafirma que los trabajadores expuestos a solventes orgánicos con polimorfismos de CYP2E1, específicamente con genotipo c1c1, tienen mayor probabilidad de presentar mutaciones en las células somáticas, condición asociada con una mayor susceptibilidad a enfermedades como el cáncer

The role of high mobility group protein 1 in toluene diisocyanate-induced NLPR3 inflammasome activation in human bronchial epithelial cells / 中国职业医学

OBJECTIVE: To investigate the role of high mobility group protein 1(HMGB1) in toluene diisocyanate(TDI) induced nucleotide-binding oligomerization domain like receptor family pyrin domain-containing 3(NLRP3) inflammasome activation in human bronchial epithelial cells(HBECs). METHODS: i) The TDI-human serum albumin(HSA) stimulation experiment: the HBECs in logarithmic growth phase were randomly divided into control group, low-, medium-and high-dose groups that were pretreated with TDI-HSA with the final concentration of 0.00, 40.00, 80.00 and 120.00 mg/L for 12 hours. ii) The HMGB1 expression inhibition experiment: the HBECs in logarithmic growth phase were divided into control group, TDI-HSA group, TDI-HAS+negative-siRNA group, and TDI-HAS+HMGB1-siRNA group. The cells in TDI-HAS+negative-siRNA group and TDI-HAS+HMGB1-siRNA group were infected with HBECs with negative-siRNA lentivirus and HMGB1-siRNA lentivirus, respectively. Cells in these two groups and the TDI-HSA group were treated with 120.00 mg/L of TDI-HSA for 12 hours. The cells in the control group were not treated with TDI-HAS. iii) The expression of HMGB1, NLRP3, apoptosis-associated speck-like protein containing CARD(ASC), pro-caspase-1 and caspase-1 p20 proteins in all groups were detected by Western blot. The number of NLRP3 and caspase-1 inflammasome in TDI-HSA stimulation experiment was observed by immunofluorescence method. RESULTS: i) TDI-HSA stimulation experiment: the relative protein expression of HMGB1 and ASC was higher in HBECs of medium-and high-dose groups than that of control group(all P values were <0.01). The relative protein expression of NLRP3 and casepase-1 p20 and the number of NLRP3-caspase-1 inflammasome were higher in HBECs of 3 dose groups than that of control group(all P values were <0.01). The number of NLRP3-caspase-1 inflammasome in HBECs increased obviously in low-, medium-and high-dose groups as compared to the control group(all P values were <0.05). The number of NLRP3-caspase-1 inflammasome in HBECs increased with the increase of TDI-HSA dose(all P values were <0.01). ii) The HMGB1 expression inhibition experiment: the relative protein expression of HMGB1, NLRP3, ASC, pro caspase-1 and caspase-1 p20 in HBECs were higher in the TDI-HSA group and TDI-HSA + negative-siRNA group than those of the control group(all P values were <0.01). The above indexes of HBECs were lower in the TDI-HAS + HMGB1-siRNA group than those in the TDI-HSA group and TDI-HSA + negative-siRNA group(all P values were <0.01).CONCLUSION: TDI treatment in HBECS can induce the increase of HMGB1 protein expression and activate NLPR3 inflammasome. Inhibition of HMGB1 expression can down-regulate the expression of NLPR3 and its related proteins.

Maternal exposure to benzene and toluene and preterm birth. A longitudinal study

ABSTRACT BACKGROUND: Exposure to air pollutants has several effects on human health, including during pregnancy. OBJECTIVE: To identify whether exposure to benzene and toluene among pregnant women contributes to preterm delivery. DESIGN AND SETTING: Longitudinal study using data on newborns from mothers living in São José dos Campos (SP) in 2016, who had been exposed to benzene and toluene. METHODS: A logistic regression model with three hierarchical levels was constructed using maternal variables relating to newborns, and using benzene and toluene concentrations in quartiles. Occurrences of cesarean births, twins or malformations were excluded. Maternal exposure windows of 5, 10, 15, 30, 60 and 90 days prior to delivery were considered. RESULTS: Out of the 9,562 live births, 3,671 newborns were included and 343 newborns were born at less than 37 weeks of gestation (9.3%). The average birth weight was 3,167.2 g. Exposure to benzene and toluene was significantly associated (P = 0.04) with preterm delivery in the five-day window. There was no association in any of the other exposure windows. CONCLUSIONS: It was possible to identify that maternal exposure to benzene and toluene has an acute effect on preterm delivery.

Toluene diisocyanate induces inflammatory response and autophagy in human bronchial epithelial cells / 中国职业医学

OBJECTIVE: To investigate the effect of toluene diisocyanate(TDI) on the activation of autophagy and expression of inflammatory cytokines interleukin(IL)-4 and IL-6 in normal human bronchial epithelial cells(16 HBE). METHODS: i) We prepared TDI-human serum albumin(HSA) and determined the mass concentration of TDI in TDI-HSA. ii) The cells were treated with TDI-HSA and HSA at concentrations of 0.00-400.00 mg/L for 12 hours. CCK-8 assay was used to determinate the cell viability, and TDI-HSA and HSA doses were selected for subsequent experiments. iii) The cells were treated with TDI-HSA and HSA at doses of 0.00-120.00 mg/L for 12 hours, and the levels of reactive oxygen species(ROS) in the cells were detected by flow cytometry. The levels of IL-4 and IL-6 in the cell supernatant were measured by enzyme-linked immunosorbent assay. iv) The cells were treated with TDI-HSA at doses of 0.00-120.00 mg/L for 12 hours, and the autophagy activity was observed under transmission electron microscope. Western blot was utilized to detect the expression of Beclin1, microtubule-associated protein 1 light chain(LC3β) and P62. RESULTS: i) The mass concentrations of TDI in 40.00, 80.00 and 120.00 mg/L TDI-HSA groups were 0.44, 0.89 and 1.33 mg/L respectively. ii) The results of CCK-8 showed that TDI-HSA and HSA at doses below 120.00 mg/L did not affect cell viability, and 0.00-120.00 mg/L was selected as the TDI-HSA and HSA treatment doses for subsequent experiments. iii) The level of ROS in cells and the levels of IL-4 and IL-6 in the supernatant of 16 HBE cells in the TDI-HSA group at 40.00, 80.00, and 120.00 mg/L were higher than that in HSA group at the same dose(P<0.01). The level of ROS in cells and the levels of IL-4 and IL-6 in the supernatant of 16 HBE cells increased with the increase of TDI-HSA doses(P<0.01). iv) Transmission electron microscopy showed that the number of autophagic lysosomes in 16 HBE cells increased significantly, and the number of mitochondrial vacuoles increased in 40.00, 80.00, 120.00 mg/L TDI-HSA group compared with 0.00 mg/L group. With the increase of TDI-HSA dose, the relative expression of Beclin1 protein and LC3β-Ⅱ/Ⅰ ratio in 16 HBE cell supernatant increased(P<0.05), and the relative expression of P62 protein decreased(P<0.05). CONCLUSION: TDI-HSA induces increased expression of ROS and inflammatory factors and induces autophagy activation in 16 HBE cells. Autophagy may be an important factor for the development of airway inflammation in TDI-induced occupational asthma.

Determination of seven urinary metabolites of benzene, toluene and xylene by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry / 中华劳动卫生职业病杂志

Objective@#To develop a method using ultra-high performance liquid chromatography-triple quadrupole mass spectrometry to determine the urinary metabolites of benzene, toluene and xylene. The selected metabolites are S-phenylmercapturic acid (S-PMA) , trans, trans-muconic acid (t, t-MA) , 8-hydroxy-2 deoxyguanosine (8-OHdG) , hippuric acid (HA) , 2-methylhippuric acid (2-MHA) , 3-methylhippuric acid (3-MHA) and 4-methylhippuric acid (4-MHA) .@*Methods@#The urine sample was pretreated using methanol to precipitate the proteins. HSS T3 chromatographic column was used to separate the metabolites. The mass spectrometric acquisition was carried out using multiple reaction monitoring (MRM) after ionization with ESI source. External standard method was used for quantification.@*Results@#All the standard curves showed good linear relation, and r of the seven metabolites was all above 0.999. The detection limits and quantitative limits of the seven metabolites were 0.01-500 ng/ml and 0.02-1 000 ng/ml (based on the actual dilution ratio) , respectively. The average spiked recoveries of four loadings ranged from 85.8% to 109.9%. The intra-day and inter-day precisions were 0.2%-4.5% and 0.6%-9.5%, respectively. The samples can be kept for at least 14 days at both 4 ℃ and -20 ℃.@*Conclusion@#This method is simple, rapid and highly sensitive with low cost, and its accuracy, precision and stability can meet the daily test requirements. It can be applied for the determination of urinary S-PMA, t, t-MA, 8-OHdG, HA, 2-MHA, 3-MHA and 4-MHA for the occupational population exposed to benzene, toluene and xylene.

Analysis of the cardiovascular effects on workers expose to occupational benzene-toluene-xylene and noise in a painting workshop of an automobile company / 中华劳动卫生职业病杂志

Objective@#To learn about the cardiovascular health effects of workers expose to benzene-toluene-xylene and noise in painting workshop of automobile manufacturing enterprises, and to provide intervention measures and strategies for the health of workers.@*Methods@#The effects of noise exposure, benzene-toluene-xylene exposure and combined exposure on workers' blood pressure and electrocardiogram were analyzed through epidemiological investigation, workplace monitoring and occupational health examination in several automobile enterprises which had carried out occupational hazard factors monitoring and occupational health examination in our hospital from April to October 2017.@*Results@#There were differences in age, sex, working years, smoking, drinking and physical exercise among workers in different exposure groups (P<0.05) . The systolic blood pressure level of workers in benzene-toluene-xylene exposure group and combined exposure group was significantly different comparing with control group (P< 0.05) , After the factors of age and working years were adjusted. The abnormity rate of electrocardiogram in workers were not statistically significant in all groups (P>0.05) .@*Conclusion@#The benzene-toluene-xylene exposure and noise combined with benzene-toluene-xylene exposure in painting workshop of automobile manufacturing enterprises has positive influence on the systolic blood pressure of workers. Regular physical examination and health intervention measures should be strengthened to improve health.

Occupational Health Risk Assessment of Low Concentrations Benzene Toluene and Xylenes / 中华劳动卫生职业病杂志

Objective@#To Assess occupational health risks of exposuring to low concentrations (lower than occupational exposure limit, OEL) benzene, toluene and Xylenes.@*Methods@#Qualitative evaluation, semi-quantitative evaluation and quantitative evaluation from guidelines for occupational health risk assessment of chemicals in the workplace were conducted to assess occupational health risks exposure to benzene compounds in different workplaces of 5 manufacturing enterprises, respectively.@*Results@#Concentrations of benzene, toluene and Xylenes in all workplaces were lower than OEL. Qualitative evaluation showed that occupational health risk level was 4 exposure to benzene and Xylenes in all workpalces, while 2 exposure to toluene. Semi-quantitative evaluation showed low level (2 of 5) risks in all workplaces exposured to benzene compounds excepted 4 workpalces exposured to benzene, the latter was moderate (3 of 5) . Quantitative evaluation gave unacceptable carcinogenic risk (higher than 10-4) of benzene in the wood toy manufactory, and the highest risk was (1.48~5.26) ×10-4. The occupational health risks of benzene and Xylenes were all unacceptable (HQ>1) in 9 workplaces.@*Conclusion@#There still need more attention to occupational health risks exposure to benzene, toluene and Xylenes lower than OEL.

Work Exposure to Traffic Air Pollutants (PM10, Benzene, Toluene, and Xylene) and Respiratory Health Implications among Urban Traffic Policemen in Klang Valley, Malaysia

@#Introduction: This study aimed to identify the exposure levels of traffic air pollutants specifically PM10, benzene, toluene, and xylene (BTX) among traffic policemen and the risks to their respiratory health. A cross-sectional comparative study was conducted among 42 traffic policemen and 42 desk-bound policemen as the exposed and comparative groups respectively. Methods: The questionnaire adapted from the American Thoracic Society for Adult Respiratory Health Disease (ATS-DLD) to obtain socio-demographic and respiratory symptoms data. A spirometer (Chestgraph Hi-105) was used to perform lung function test. A personal air sampling pump was used to measure the personal exposure level to PM10. A Ppbrae 3000 was used to measure the outdoor and indoor concentration of BTX during morning and afternoon peak hours respectively. Results: The mean personal exposure level of PM10 among the traffic policemen was 150.14 ± 130.66 µg/m3 compared to only 84.14 ± 94.11 µg/m3 in the comparative group. The short exposures to BTX at the roadsides were found to be slightly higher in the afternoons than in the mornings. Indoor offices air concentrations were only detectable for benzene while the mornings and afternoons values for toluene and xylene were below the detection limits. A median concentration of benzene documented significantly higher at the selected of sampling roadsides areas (median=0.157 ppm) than indoor office areas (median=0.071 ppm). Conclusion: The respiratory symptoms were significantly higher in the exposed group compared to the comparative group which they were 3.9, 4.1, and 3.5 times more likely to develop cough, wheezing, and breathlessness respectively.

The changes of ROR-γt,IL-17A and Foxp3 mRNA expression and promoter methylation in TDI-induced mouse asthma / 中国职业医学

OBJECTIVE: To explore the changes of retinoic acid related orphan receptor-γt( ROR-γt),interleukin( IL)-17 A and forkhead / winged helix protein 3( Foxp3) mRNA expression and promoter methylation in the process of asthma induced by toluene-diisocyanate( TDI). METHODS: Specific pathogens free grade healthy male BALB / c mice were randomly assigned into asthma group and control group with 18 animals in each group. In the asthma group,the mice were sensitized with 0. 30% TDI( mass-volume concentration) dropped on the dorsum of both ears( 20 μL / ear) on day 1 and day 8. On day 15,the mice were challenged with 20 μL 0. 01% TDI( mass-volume concentration) by the trachea. The control group mice were sensitized and challenged by the same procedures with the same amount of solvent( acetone / olive oil). The mice were challenged 24 hours,the pathological changes of trachea and lung tissues were observed. The bronchoalveolar lavage fluid( BALF) from each group was collected,and the inflammatory cells in BALF were counted and classified. IL-4and Interferon-γ( IFN-γ) levels in BALF supernatant were measured by enzyme-linked immunosorbent assay. ROR-γt,IL-17 A and Foxp3 mRNA expression in the lung tissue were measured by real-time fluorescent quantitative polymease chain reaction. The degree of ROR-γt,IL-17 A and Foxp3 promoter methylation in lung issue were detected by Mass Array system.RESULTS: The asthmatic group demonstrated the symptoms of acute asthma,such as breathing deeply and fastly,bowing the back,lifting the forelimbs,et al. But the control group had no such symptoms in mice. Hematoxylin-Eosin staining showed obvious inflammatory lesions in the trachea and lung tissue of asthmatic mice. Compared with the control group,the white blood cell count,the neutrophil and eosinophil percentages in BALF,the IL-4,IFN-γ levels in BALF supernatant in asthma group were all significantly increased( P < 0. 01),meanwhile the lymphocyte and monocyte percentages in BALF were reduced( P < 0. 01); ROR-γt mRNA expression was significantly increased( P < 0. 01),and the degree of promoter methylation from sites 3,4,5,6,8,11 and 12 was significantly reduced( P < 0. 05); IL-17 A mRNA expression was significantly increased( P < 0. 01),and the degree of promoter methylation from sites 6 and 7 was significantly reduced( P < 0. 01); Foxp3 mRNA expression was significantly reduced( P < 0. 01),and the degree of promoter methylation from sites 1 and 10 was significantly increased( P < 0. 01). CONCLUSION: Th17 / Treg cell immune imbalance occurs in asthma induced by TDI. ROR-γt,IL-17 A and Foxp3 gene promoter methylation abnormalities may be involved in Th17 / Treg cell immune imbalance.

Modeling the effects of pollutant emissions from large industrial complexes on benzene, toluene, and xylene concentrations in urban areas

This study utilized the Community Multiscale Air Quality model to simulate the spatial distribution of benzene, toluene, and xylene (BTX) concentrations from large national industrial complexes (IC) located in the Ulsan metropolitan region (UMR). Through controlling pollutant emissions from major IC, this study performed a quantitative analysis of the influence of pollutant emissions on BTX concentrations in surrounding urban areas. The results showed that approximately 40% of the annual average BTX concentrations in nearby urban grids were directly influenced by pollutant emissions from the IC. Seasonal modeling results indicated that average BTX concentrations were high around petrochemical complexes, with higher concentrations in the surrounding urban areas during the summer (July). All three of the BTX pollutants showed similar seasonal differences. Daily contributions differed significantly throughout the modeling period, with some values reaching a maximum of 80% during July. Overall, when urban areas were located downwind of the IC, contributions rose. Moreover, this study compared the differences in BTX contributions at each measurement point within the IC and urban areas, which showed that the influence of the IC emissions decreased significantly with distance. The spatial distribution and direct influence of the IC on BTX concentrations in the UMR identified through this study could be used to provide input data in environmental epidemiological studies.

Simultaneous Determination of 5 Organic Solvents in Favipiravir by Headspace GC / 中国药房

OBJECTIVE:To establish a method for simultaneous determination of 5 kinds residual ethanol,acetone,ethylacetate,N,N-diisopropylethylamine and toluene in favipiravir.METHODS:Headspace GC was adopted.The determination was performed on DB-624 capillary column,temperature programmed.The inlet temperature was 220 ℃,and detector was flame ionization detector with temperature of 250 ℃.Nitrogen was used as carrier gas at flow rate of 2.0 mL/min,split ratio was 10 ∶ 1,headspace equilibrium temperature was 80 ℃,equilibrium time was 20 min and headspace sample size was 1 mL.RESULTS:The linear range was 10.0-501.4 μg/mL for ethanol(r=0.999 9),10.0-501.4 μg/mL for acetone (r=0.999 9),10.1-502.6 μg/mL for ethylacetate (r=0.999 9),0.2-11.4 μg/mL for N,N-diisopropylethylamine (r=0.999 9)and 1.8-89.4 μg/mL for acetone(r=0.999 7).The limits of quantification were 5.3,3.4,5.2,6.1 and 20.4 μg/mL,and the limits of detection were 1.4,1.1,1.3,1.6,5.9 μg/mL.RSD of precision test was lower than 4.0％,and RSDs of acetone in stability and reproducibility tests were both lower than 4.0％.The recoveries were 96.61％-99.70％ (RSD=1.01％,n=9),95.81％-99.50％ (RSD=1.29％,n=9),96.42％-99.76％ (RSD=1.24％,n=9),96.36％-99.30％ (RSD=1.19％,n=9),97.00％-99.51％ (RSD=0.82％,n=9).CONCLUSIONS:The method is simple,accurate,reproducible and can be used for simultaneous determination of 5 organic solvents in favipiravir.