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Zhuang Y, Li L, Zhang Y, Liu X, Zeng B, Zhu B, Dai F. Single and mixed effects of multiple volatile organic compounds exposure on hematological parameters in the U.S. adult population. CHEMOSPHERE 2024; 355:141825. [PMID: 38552802 DOI: 10.1016/j.chemosphere.2024.141825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/26/2024] [Accepted: 03/26/2024] [Indexed: 04/18/2024]
Abstract
BACKGROUND Most research exploring the correlation between volatile organic compounds (VOCs) and hematological parameters have focused on single VOCs. Our study aimed to explore the single and combined effects of VOCs on hematological parameters through three statistical models. METHODS Data from 4 cycles of the National Health and Nutrition Examination Survey (NHANES) were used in this study. The correlations between single exposure to 16 VOCs and hematological parameters in the general population were assessed by weighted multiple linear regression. Weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models were used to explore the relationship between the combined important VOCs selected by the least absolute shrinkage and selection operator (LASSO) and hematological parameters, as well as the effects of smoking status on them. RESULTS A total of 4089 adults were included in the study. We found that a variety of VOCs were significantly associated with hematological parameters. Among them, N-acetyl-S-(benzyl)-l-cysteine (BMA) was significantly negatively correlated with white blood cell (WBC), red blood cell (RBC), lymphocyte, and neutrophil counts. N-acetyl-S-(3-hydroxypropyl-1-methyl)-l-cysteine (HPMMA) was significantly positively correlated with WBC, monocyte, lymphocyte, and neutrophil counts. In the WQS analysis, the WQS index of the VOCs mixtures was positively correlated with WBC (β: 0.031; P < 0.001), monocyte (0.023; P = 0.021), and neutrophil (0.040; P = 0.001) counts, while negatively associated with RBC (-0.013; P < 0.001) counts. The BKMR model revealed that combined exposure to VOCs levels ≥70th percentile was significantly associated with lower RBC counts, and BMA was identified as the dominant contributor. Smoking significantly influenced the relationship between VOCs and hematological parameters. CONCLUSIONS Our study indicated the effects of single and overall VOCs exposure on hematological parameters and suggested the hematotoxicity as well as pro-inflammatory effects of VOCs, which had strong public health implications for reducing the potential health hazards of VOCs exposure to the hematologic system.
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Affiliation(s)
- Yan Zhuang
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Laifu Li
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Yanqi Zhang
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Xuna Liu
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Beibei Zeng
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Boxu Zhu
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Fei Dai
- Department of Gastroenterology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
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Hussain MS, Gupta G, Mishra R, Patel N, Gupta S, Alzarea SI, Kazmi I, Kumbhar P, Disouza J, Dureja H, Kukreti N, Singh SK, Dua K. Unlocking the secrets: Volatile Organic Compounds (VOCs) and their devastating effects on lung cancer. Pathol Res Pract 2024; 255:155157. [PMID: 38320440 DOI: 10.1016/j.prp.2024.155157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 02/08/2024]
Abstract
Lung cancer (LCs) is still a serious health problem globally, with many incidences attributed to environmental triggers such as Volatile Organic Compounds (VOCs). VOCs are a broad class of compounds that can be released via various sources, including industrial operations, automobile emissions, and indoor air pollution. VOC exposure has been linked to an elevated risk of lung cancer via multiple routes. These chemicals can be chemically converted into hazardous intermediate molecules, resulting in DNA damage and genetic alterations. VOCs can also cause oxidative stress, inflammation, and a breakdown in the cellular protective antioxidant framework, all of which contribute to the growth of lung cancer. Moreover, VOCs have been reported to alter critical biological reactions such as cell growth, apoptosis, and angiogenesis, leading to tumor development and metastasis. Epidemiological investigations have found a link between certain VOCs and a higher probability of LCs. Benzene, formaldehyde, and polycyclic aromatic hydrocarbons (PAHs) are some of the most well-researched VOCs, with comprehensive data confirming their cancer-causing potential. Nevertheless, the possible health concerns linked with many more VOCs and their combined use remain unknown, necessitating further research. Identifying the toxicological consequences of VOCs in LCs is critical for establishing focused preventative tactics and therapeutic strategies. Better legislation and monitoring mechanisms can limit VOC contamination in occupational and environmental contexts, possibly reducing the prevalence of LCs. Developing VOC exposure indicators and analyzing their associations with genetic susceptibility characteristics may also aid in early identification and targeted therapies.
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Affiliation(s)
- Md Sadique Hussain
- School of Pharmaceutical Sciences, Jaipur National University, Jagatpura, Jaipur, Rajasthan 302017, India
| | - Gaurav Gupta
- Centre for Global Health Research, Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, India; Centre of Medical and Bio-allied Health Sciences Research, Ajman University, Ajman, 346, United Arab Emirates; School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Riya Mishra
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Neeraj Patel
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Saurabh Gupta
- Chameli Devi Institute of Pharmacy, Department of Pharmacology, Khandwa Road, Village Umrikheda, Near Toll booth, Indore, Madhya Pradesh 452020, India
| | - Sami I Alzarea
- Department of Pharmacology, College of Pharmacy, Jouf University, Sakaka, 72341, Al-Jouf, Saudi Arabia
| | - Imran Kazmi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, 21589, Jeddah, Saudi Arabia.
| | - Popat Kumbhar
- Tatyasaheb Kore College of Pharmacy, Warananagar, Tal: Panhala Dist: Kolhapur, Maharashtra 416113, India
| | - John Disouza
- Tatyasaheb Kore College of Pharmacy, Warananagar, Tal: Panhala Dist: Kolhapur, Maharashtra 416113, India
| | - Harish Dureja
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak 124001, India
| | - Neelima Kukreti
- School of Pharmacy, Graphic Era Hill University, Dehradun 248007, India
| | - Sachin Kumar Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab 144411, India; Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Kamal Dua
- Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, NSW 2007, Australia; Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, NSW 2007, Australia.
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Zhang Z, Liu X, Guo C, Zhang X, Zhang Y, Deng N, Lai G, Yang A, Huang Y, Dang S, Zhu Y, Xing X, Xiao Y, Deng Q. Hematological Effects and Benchmark Doses of Long-Term Co-Exposure to Benzene, Toluene, and Xylenes in a Follow-Up Study on Petrochemical Workers. TOXICS 2022; 10:502. [PMID: 36136467 PMCID: PMC9501893 DOI: 10.3390/toxics10090502] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/19/2022] [Accepted: 08/24/2022] [Indexed: 06/16/2023]
Abstract
Benzene, toluene, and xylenes (BTX) commonly co-exist. Exposure to individual components and BTX-rich mixtures can induce hematological effects. However, the hematological effects of long-term exposure to BTX are still unclear, and respective reference levels based on empirical evidence should be developed. We conducted a follow-up study in BTX-exposed petrochemical workers. Long-term exposure levels were quantified by measuring cumulative exposure (CE). Generalized weighted quantile sum (WQS) regression models and Benchmark Dose (BMD) Software were used to evaluate their combined effects and calculate their BMDs, respectively. Many hematologic parameters were significantly decreased at the four-year follow-up (p < 0.05). We found positive associations of CE levels of benzene, toluene, and xylene with the decline in monocyte counts, lymphocyte counts, and hematocrit, respectively (β > 0.010, Ptrend < 0.05). These associations were stronger in subjects with higher baseline parameters, males, drinkers, or overweight subjects (Pinteraction < 0.05). BTX had positive combined effects on the decline in monocyte counts, red-blood-cell counts, and hemoglobin concentrations (Ptrend for WQS indices < 0.05). The estimated BMDs for CE levels of benzene, toluene, and xylene were 2.138, 1.449, and 2.937 mg/m3 × year, respectively. Our study demonstrated the hematological effects of long-term BTX co-exposure and developed 8h-RELs of about 0.01 ppm based on their hematological effects.
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Affiliation(s)
- Zhaorui Zhang
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xin Liu
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Chaofan Guo
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xinjie Zhang
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Yingying Zhang
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Na Deng
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Guanchao Lai
- Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, China
| | - Aichu Yang
- Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, China
| | - Yongshun Huang
- Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, China
| | - Shanfeng Dang
- Occupational Disease Prevention and Treatment Institute of Sinopec Maoming Petrochemical Company, Maoming 525000, China
| | - Yanqun Zhu
- Occupational Disease Prevention and Treatment Institute of Sinopec Maoming Petrochemical Company, Maoming 525000, China
| | - Xiumei Xing
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Yongmei Xiao
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Qifei Deng
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
- School of Public Health, Guangzhou Medical University, Guangzhou 511436, China
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Epigenetic Effects of Benzene in Hematologic Neoplasms: The Altered Gene Expression. Cancers (Basel) 2021; 13:cancers13102392. [PMID: 34069279 PMCID: PMC8156840 DOI: 10.3390/cancers13102392] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/06/2021] [Accepted: 05/11/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Benzene is produced by diverse petroleum transformation processes and it is widely employed in industry despite its oncogenic effects. In fact, occupational exposure to benzene may cause hematopoietic malignancy. The leukemogenic action of benzene is particularly complex. Possible processes of onset of hematological malignancies have been recognized as a genotoxic action and the provocation of immunosuppression. However, benzene can induce modifications that do not involve alterations in the DNA sequence, the so-called epigenetics changes. Acquired epigenetic modification may also induce leukemogenesis, as benzene may alter nuclear receptors, and cause changes at the protein level, thereby modifying the function of regulatory proteins, including oncoproteins and tumor suppressor proteins. Abstract Benzene carcinogenic ability has been reported, and chronic exposure to benzene can be one of the risk elements for solid cancers and hematological neoplasms. Benzene is acknowledged as a myelotoxin, and it is able to augment the risk for the onset of acute myeloid leukemia, myelodysplastic syndromes, aplastic anemia, and lymphomas. Possible mechanisms of benzene initiation of hematological tumors have been identified, as a genotoxic effect, an action on oxidative stress and inflammation and the provocation of immunosuppression. However, it is becoming evident that genetic alterations and the other causes are insufficient to fully justify several phenomena that influence the onset of hematologic malignancies. Acquired epigenetic alterations may participate with benzene leukemogenesis, as benzene may affect nuclear receptors, and provoke post-translational alterations at the protein level, thereby touching the function of regulatory proteins, comprising oncoproteins and tumor suppressor proteins. DNA hypomethylation correlates with stimulation of oncogenes, while the hypermethylation of CpG islands in promoter regions of specific tumor suppressor genes inhibits their transcription and stimulates the onset of tumors. The discovery of the systems of epigenetic induction of benzene-caused hematological tumors has allowed the possibility to operate with pharmacological interventions able of stopping or overturning the negative effects of benzene.
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Davidson CJ, Hannigan JH, Bowen SE. Effects of inhaled combined Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX): Toward an environmental exposure model. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2021; 81:103518. [PMID: 33132182 DOI: 10.1016/j.etap.2020.103518] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Combined environmental exposures to the volatile organic compounds (VOCs) Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) pose clear risks to public health. Research into these risks is under-studied even as BTEX levels in the atmosphere are predicted to rise. This review focuses on the available literature using single- and combined-BTEX component inhaled solvent exposures in animal models, necessarily also drawing on findings from models of inhalant abuse and occupational exposures. Health effects of these exposures are discussed for multiple organ systems, but with particular attention on neurobehavioral outcomes such as locomotor activity, impulsivity, learning, and psychopharmacological responses. It is clear that animal models have significant differences in the concentrations, durations and patterns of exposure. Experimental evidence of the deleterious health and neurobehavioral consequences of exposures to the individual components of BTEX were found, but these effects were typically assessed using concentrations and exposure patterns not characteristic of environmental exposure. Future studies with animal models designed appropriately to explore combined BTEX will be necessary and advantageous to discovering health outcomes and more subtle neurobehavioral impacts of long-term environmental exposures.
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Affiliation(s)
| | - John H Hannigan
- Department of Psychology, Wayne State University, Detroit, MI, USA; Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA; Merrill Palmer Skillman Institute for Child & Family Development, Wayne State University, Detroit, MI, USA; Center for Urban Responses to Environmental Stressors, Wayne State University, Detroit, MI, USA
| | - Scott E Bowen
- Department of Psychology, Wayne State University, Detroit, MI, USA; Center for Urban Responses to Environmental Stressors, Wayne State University, Detroit, MI, USA.
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Chen Q, Sun H, Zhang J, Xu Y, Ding Z. The hematologic effects of BTEX exposure among elderly residents in Nanjing: a cross-sectional study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:10552-10561. [PMID: 30761498 DOI: 10.1007/s11356-019-04492-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 02/05/2019] [Indexed: 06/09/2023]
Abstract
Few studies have examined the effects of environmental concentrations of benzene, toluene, ethylbenzene, and xylene (BTEX) on the hematologic system of residents near a petrochemical complex. This study evaluated the potential effects of blood BTEX concentrations on the hematologic parameters of residents in a community near a petrochemical complex (contaminated group) and another community free of known petrochemical pollution (control group). Volunteer residents were randomly recruited. Each participant completed a questionnaire and donated blood samples to evaluate blood BTEX concentrations and hematologic parameters. We found the mean concentrations of blood BTEX of the contaminated group were 1.2 to 6.7 times higher than the control group. Multiple hematologic parameters of participants were significantly different between the two study groups. Inverse associations were found for ln-transformed blood benzene concentrations with mean corpuscular hemoglobin concentration (MCHC) (β = - 2.75) and platelet counts (β = -8.18). Several weaker associations were also observed between other compounds and multiple hematologic parameters. Our results suggest that the residents living near petrochemical complexes have higher blood BTEX concentrations. Furthermore, the increased blood BTEX levels in residents are associated with the reduction in RBC counts, hemoglobin concentration, hematocrit, MCHC, and platelet counts. This study provided particularly important information for the health risk assessment of residents living near petrochemical complexes.
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Affiliation(s)
- Qi Chen
- Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu, Road 172, 210009, Nanjing, People's Republic of China
| | - Hong Sun
- Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu, Road 172, 210009, Nanjing, People's Republic of China
| | - Jiayao Zhang
- Nanjing Medical University, Longmian Road 101, Jiangning District, 210029, Nanjing, People's Republic of China
| | - Yan Xu
- Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu, Road 172, 210009, Nanjing, People's Republic of China
| | - Zhen Ding
- Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu, Road 172, 210009, Nanjing, People's Republic of China.
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Méausoone C, El Khawaja R, Tremolet G, Siffert S, Cousin R, Cazier F, Billet S, Courcot D, Landkocz Y. In vitro toxicological evaluation of emissions from catalytic oxidation removal of industrial VOCs by air/liquid interface (ALI) exposure system in repeated mode. Toxicol In Vitro 2019; 58:110-117. [PMID: 30910524 DOI: 10.1016/j.tiv.2019.03.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/05/2019] [Accepted: 03/21/2019] [Indexed: 12/11/2022]
Abstract
Toxicity of toluene and by-products formed during its catalytic oxidative degradation was studied in human bronchial BEAS-2B cells repeatedly exposed. BEAS-2B cells were exposed using an Air-Liquid Interface (ALI) System (Vitrocell®) for 1 h per day during 1, 3 or 5 days to gaseous flows: toluene vapors (100 and 1000 ppm) and outflow after catalytic oxidation of toluene (10 and 100%). After exposure to gaseous flow, cytotoxicity, inflammatory response and Xenobiotic Metabolism Enzymes (XME) gene expression were investigated. No significant cytotoxicity was found after 5 days for every condition of exposure. After cells exposure to catalytic oxidation flow, IL-6 level increased no significantly in a time- and dose-dependent way, while an inverted U-shaped profile of IL-8 secretion was observed. XME genes induction, notably CYP2E1 and CYP2F1 results were in line with the presence of unconverted toluene and benzene formed as a by-product, detected by analytical methods. Exposure to pure toluene also demonstrated the activation of these XMEs involved in its metabolism. Repeated exposure permits to show CYP1A1, CYP1B1 and CY2S1 expression, probably related to the formation of other by-products, as PAHs, not detected by standard analytical methods used for the development of catalysts.
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Affiliation(s)
- Clémence Méausoone
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Rebecca El Khawaja
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Gauthier Tremolet
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Stéphane Siffert
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Renaud Cousin
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Fabrice Cazier
- Centre Commun de Mesure, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Sylvain Billet
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Dominique Courcot
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France..
| | - Yann Landkocz
- UCEIV - EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France
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Jørgensen KM, Færgestad Mosleth E, Hovde Liland K, Hopf NB, Holdhus R, Stavrum AK, Gjertsen BT, Kirkeleit J. Global Gene Expression Response in Peripheral Blood Cells of Petroleum Workers Exposed to Sub-Ppm Benzene Levels. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15112385. [PMID: 30373255 PMCID: PMC6266895 DOI: 10.3390/ijerph15112385] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/21/2018] [Accepted: 10/24/2018] [Indexed: 01/14/2023]
Abstract
Altered gene expression in pathways relevant to leukaemogenesis, as well as reduced levels of circulating lymphocytes, have been reported in workers that were exposed to benzene concentrations below 1 ppm. In this study, we analysed whole blood global gene expression patterns in a worker cohort with altered levels of T cells and immunoglobulins IgM and IgA at three time points; pre-shift, post-shift (after three days), and post-recovery (12 hours later). Eight benzene exposed tank workers performing maintenance work in crude oil cargo tanks with a mean benzene exposure of 0.3 ppm (range 0.1–0.5 ppm) and five referents considered to be unexposed were examined by gene expression arrays. By using our data as independent validation, we reanalysed selected genes that were reported to be altered from previous studies of workers being exposed to sub-ppm benzene levels Four out of six genes previously proposed as marker genes in chronically exposed workers separated benzene exposed workers from unexposed referents (CLEC5, ACSL1, PRG2, IFNB1). Even better separation of benzene exposed workers and referents was observed for short-term exposure for genes in the Jak-STAT pathway, particularly elevated expression of IL6 and reduced expression of IL19.
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Affiliation(s)
- Katarina M Jørgensen
- Department of Clinical Science, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
- Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817 Bergen, Norway.
| | | | - Kristian Hovde Liland
- Nofima AS, Osloveien 1, N-1430 Ås, Norway.
- Faculty of Science and Technology, Norwegian University of Life Sciences, NO-1430 Ås, Norway.
| | - Nancy B Hopf
- Institute for Work and Health (IST), Universities of Lausanne and Geneva, CH-1066 Lausanne-Epalinges, Switzerland.
| | - Rita Holdhus
- Department of Clinical Science, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
- Department of Medical Genetics, Haukeland University Hospital, P.O. Box 1400, N-5021 Bergen, Norway.
| | - Anne-Kristin Stavrum
- Department of Clinical Science, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
- Department of Medical Genetics, Haukeland University Hospital, P.O. Box 1400, N-5021 Bergen, Norway.
| | - Bjørn Tore Gjertsen
- Center for Cancer Biomarkers (CCBIO), Department of Clinical Science, Precision Oncology Research Group, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
| | - Jorunn Kirkeleit
- Department of Clinical Science, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
- Department of Global Public Health and Primary Care, University of Bergen, P.O. Box 7804, N-5020 Bergen, Norway.
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9
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Jiménez-Garza O, Guo L, Byun HM, Carrieri M, Bartolucci GB, Barrón-Vivanco BS, Baccarelli AA. Aberrant promoter methylation in genes related to hematopoietic malignancy in workers exposed to a VOC mixture. Toxicol Appl Pharmacol 2017; 339:65-72. [PMID: 29217486 DOI: 10.1016/j.taap.2017.12.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/30/2017] [Accepted: 12/03/2017] [Indexed: 12/20/2022]
Abstract
Occupational exposure to volatile organic compounds (VOCs) may cause hematopoietic malignancy, either by single exposure to benzene or possibly due to a concomitant exposure to several VOCs. Since oxidative stress, inflammation and DNA repair pathways are closely involved in cancer development, the effect of VOC exposure on expression of proteins involved in these pathways has been studied, but epigenetic changes have not been well described. Here, DNA methylation status following occupational exposure to a VOC mixture was assessed by bisulfite sequencing of the promoter regions of seven genes involved in the mentioned pathways. Peripheral blood samples and individual-level VOC exposure data were obtained from healthy leather shoe factory workers (LS, n=40) and gas station attendants (GS, n=36), as well as a reference group of university employees (C, n=66). Exposure levels for acetone, ethylbenzene, methyl ethyl ketone, n-hexane, toluene and xylene were higher in LS (p<0.001); benzene and methyl acetate levels were higher in GS (p<0.001). TOP2A, SOD1, and TNF-α promoter methylation status was increased in LS (p<0.05). In LS, we also found significant correlations between GSTP1 promoter methylation and both iNOS (r=0.37, p=0.008) and COX-2 (r=-0.38, p=0.007) methylation. In exposed groups, ethylbenzene exposure levels showed a significant correlation with TOP2A methylation (β=0.33). Our results show early, toxic effects at the epigenetic level caused by occupational exposure to high levels of a VOC mixture. These subcellular modifications may represent the initial mechanism of toxicity leading to hematopoietic malignancy, possibly due to a synergistic, hematotoxic effect of VOC mixtures.
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Affiliation(s)
- Octavio Jiménez-Garza
- Health Sciences Division, University of Guanajuato, León, Campus. Blvd. Puente del Mienio 1001, Fracción del Predio San Carlos, C.P. 37670 León Guanajuato, Mexico.
| | - Liqiong Guo
- Department of Occupational & Environmental Health, Tianjin Medical University, No.22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Hyang-Min Byun
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE4 5PL, United Kingdom
| | - Mariella Carrieri
- Department of Cardiologic, Thoracic and Vascular Science, University of Padova, Via Giustiniani, 2, 35128 Padova, Italy
| | - Giovanni Battista Bartolucci
- Department of Cardiologic, Thoracic and Vascular Science, University of Padova, Via Giustiniani, 2, 35128 Padova, Italy
| | - Briscia Socorro Barrón-Vivanco
- The Laboratory of Environmental Toxicology and Pollution, Autonomous University of Nayarit, Av de la Cultura Amado Nervo S/N, CP 36000 Tepic, Nayarit, Mexico
| | - Andrea A Baccarelli
- The Laboratory of Human Environmental Epigenetics, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA
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10
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Jiménez-Garza O, Guo L, Byun HM, Carrieri M, Bartolucci GB, Zhong J, Baccarelli AA. Promoter methylation status in genes related with inflammation, nitrosative stress and xenobiotic metabolism in low-level benzene exposure: Searching for biomarkers of oncogenesis. Food Chem Toxicol 2017; 109:669-676. [DOI: 10.1016/j.fct.2017.08.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 08/15/2017] [Indexed: 12/13/2022]
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11
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Villalba-Campos M, Chuaire-Noack L, Sánchez-Corredor MC, Rondón-Lagos M. High chromosomal instability in workers occupationally exposed to solvents and paint removers. Mol Cytogenet 2016; 9:46. [PMID: 27325915 PMCID: PMC4913430 DOI: 10.1186/s13039-016-0256-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 06/09/2016] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Painters are exposed to an extensive variety of harmful substances like aromatic hydrocarbons used as solvents and paint removers, some of which have shown clastogenic activity. These substances constitute a complex mixture of chemicals which contain well-known genotoxicants, such as Benzene, Toluene and Xylene. Thus, chronic occupational exposure to such substances may be considered to possess genotoxic risk. In Colombia the information available around the genotoxic damage (Chromosomal and DNA damage) in car paint shop workers is limited and the knowledge of this damage could contribute not only to a better understanding of the carcinogenic effect of this kind of substances but also could be used as biomarkers of occupational exposure to genotoxic agents. RESULTS In this study, the genotoxic effect of aromatic hydrocarbons was assessed in peripheral blood lymphocytes of 24 workers occupationally exposed and 24 unexposed donors, by using Cytogenetic analysis and comet assay. A high frequency of Chromosomal alterations was found in the exposed group in comparison with those observed in the unexposed group. Among the total of CAs observed in the exposed group, fragilities were most frequently found (100 %), followed by chromosomal breaks (58 %), structural (41.2 %) and numerical chromosomal alterations (21 %). Numerical chromosomal alterations, fragilities and chromosomal breaks showed significant differences between exposed and unexposed groups. Among the fragilities, fra(9)(q12) was the most frequently observed. DNA damage index was also significantly higher in the exposed group compared to the unexposed group (p < 0.000). CONCLUSIONS Our results revealed that occupational exposure to aromatic hydrocarbons is significantly associated with Chromosomal and DNA damage in car paint shops workers and are also indicative of high chromosomal instability. The high frequency of both Chromosomal Alterations and DNA Damage Index observed in this study indicates an urgent need of intervention not only to prevent the increased risk of developing cancer but also to the application of strict health control and motivation to the use of appropriate protecting devices during work.
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Affiliation(s)
- Mónica Villalba-Campos
- />Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, DC Colombia
| | - Lilian Chuaire-Noack
- />Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, DC Colombia
| | | | - Milena Rondón-Lagos
- />Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, DC Colombia
- />Department of Medical Sciences, University of Turin, Via Santena 7, 10126 Turin, Italy
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12
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CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit. Toxicol Appl Pharmacol 2015; 286:207-15. [DOI: 10.1016/j.taap.2015.04.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 04/08/2015] [Accepted: 04/29/2015] [Indexed: 12/31/2022]
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13
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Mckee RH, Adenuga MD, Carrillo JC. Characterization of the toxicological hazards of hydrocarbon solvents. Crit Rev Toxicol 2015; 45:273-365. [DOI: 10.3109/10408444.2015.1016216] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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Sha Y, Zhou W, Yang Z, Zhu X, Xiang Y, Li T, Zhu D, Yang X. Changes in poly(ADP-ribosyl)ation patterns in workers exposed to BTX. PLoS One 2014; 9:e106146. [PMID: 25215535 PMCID: PMC4162541 DOI: 10.1371/journal.pone.0106146] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 07/28/2014] [Indexed: 11/18/2022] Open
Abstract
Occupational exposure to (benzene, toluene and xylene, BTX is common in the Chinese workplace. Chronic occupational exposure to benzene is associated with an increased risk of hematological malignancies such as acute myeloid leukemia (AML), but the underlying mechanisms are still unclear. This study investigates changes in poly(ADP-ribosyl)ation and DNA methylation in subjects occupationally exposed to a BTX. Blood DNA samples and exposure data were obtained from subjects with different levels of exposure, including 132 decorators, 129 painters, and 130 unexposed referents in a container-manufacturing factory in Shenzhen, China. Occupational exposure assessment included personal monitoring of airborne benzene, toluene and xylene. Hematological parameters were measured and the cytokinesis-block micronucleus (CBMN) assay was used to detect DNA damage in peripheral lymphocytes. Quantitative real-time PCR was used to detect the mRNA expression of poly(ADP-ribose) polymerase 1 (PARP1) and poly(ADP-ribose) glycohydrolase (PARG), DNA methyltransferases (DNMTs) including DNMT1, DNMT3a and DNMT3b, methyl-CpG-binding domain protein 2(MBD2). PARP1 assay was used to measure PARP activity. Airborne levels of benzene, toluene and xylene in the two exposed groups were significantly higher than those of controls (P<0.001). The two exposed groups (decorators, painters) showed decreased PARP1, DNMTs and MBD2 expression relative to controls (P<0.05), and PARP activity was also decreased (P<0.05). Decreased PARP1, DNMT1, DNMT3a, DNMT3b and MBD2 mRNA expression was correlated with increased airborne BTX (Pearson's r: -0.587, -0.314, -0.636, -0.567 and -0.592 respectively, P<0.001). No significant differences in hematological parameters and CBMN were found among the three groups. Together, these results suggest that decreased DNMTs, MBD2 and PARP1 might be involved in the global hypomethylation associated with BTX exposure, and the imbalance of PARP/PARG might participate in the down-regulation of DNMTs. This is the first human study to link altered poly(ADP-ribosyl)ation patterns, which reproduce the aberrant epigenetic patterns found in benzene-treated cells, to chronic occupational exposure to BTX.
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Affiliation(s)
- Yan Sha
- Department of Education and Research, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Wei Zhou
- Department of Occupational Hazard Assessment, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Zhenyu Yang
- Department of Occupational Hazard Assessment, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Xiaoling Zhu
- Department of Occupational Hazard Assessment, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Yingping Xiang
- Department of Occupational Hazard Assessment, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Tiandi Li
- Physicochemical Laboratory, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Dexiang Zhu
- Department of Integrated Services, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
| | - Xinyue Yang
- Department of Education and Research, Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, Guangdong, China
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15
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Micronuclei in bone marrow and liver in relation to hepatic metabolism and antioxidant response due to coexposure to chloroform, dichloromethane, and toluene in the rat model. BIOMED RESEARCH INTERNATIONAL 2014; 2014:425070. [PMID: 24949447 PMCID: PMC4053251 DOI: 10.1155/2014/425070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/24/2014] [Indexed: 01/03/2023]
Abstract
Genotoxicity in cells may occur in different ways, direct interaction, production of electrophilic metabolites, and secondary genotoxicity via oxidative stress. Chloroform, dichloromethane, and toluene are primarily metabolized in liver by CYP2E1, producing reactive electrophilic metabolites, and may also produce oxidative stress via the uncoupled CYP2E1 catalytic cycle. Additionally, GSTT1 also participates in dichloromethane activation. Despite the oxidative metabolism of these compounds and the production of oxidative adducts, their genotoxicity in the bone marrow micronucleus test is unclear. The objective of this work was to analyze whether the oxidative metabolism induced by the coexposure to these compounds would account for increased micronucleus frequency. We used an approach including the analysis of phase I, phase II, and antioxidant enzymes, oxidative stress biomarkers, and micronuclei in bone marrow (MNPCE) and hepatocytes (MNHEP). Rats were administered different doses of an artificial mixture of CLF/DCM/TOL, under two regimes. After one administration MNPCE frequency increased in correlation with induced GSTT1 activity and no oxidative stress occurred. Conversely, after three-day treatments oxidative stress was observed, without genotoxicity. The effects observed indicate that MNPCE by the coexposure to these VOCs could be increased via inducing the activity of metabolism enzymes.
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16
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Knutsen JS, Kerger BD, Finley B, Paustenbach DJ. A calibrated human PBPK model for benzene inhalation with urinary bladder and bone marrow compartments. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2013; 33:1237-1251. [PMID: 23278103 DOI: 10.1111/j.1539-6924.2012.01927.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A physiologically-based pharmacokinetic (PBPK) model of benzene inhalation based on a recent mouse model was adapted to include bone marrow (target organ) and urinary bladder compartments. Empirical data on human liver microsomal protein levels and linked CYP2E1 activities were incorporated into the model, and metabolite-specific conversion rate parameters were estimated by fitting to human biomonitoring data and adjusting for background levels of urinary metabolites. Human studies of benzene levels in blood and breath, and phenol levels in urine were used to validate the rate of human conversion of benzene to benzene oxide, and urinary benzene metabolites from Chinese benzene worker populations provided model validation for rates of human conversion of benzene to muconic acid (MA) and phenylmercapturic acid (PMA), phenol (PH), catechol (CA), hydroquinone (HQ), and benzenetriol (BT). The calibrated human model reveals that while liver microsomal protein and CYP2E1 activities are lower on average in humans compared to mice, the mouse also shows far lower rates of benzene conversion to MA and PMA, and far higher conversion of benzene to BO/PH, and of BO/PH to CA, HQ, and BT. The model also differed substantially from existing human PBPK models with respect to several metabolic rate parameters of importance to interpreting benzene metabolism and health risks in human populations associated with bone marrow doses. The model provides a new methodological paradigm focused on integrating linked human liver metabolism data and calibration using biomonitoring data, thus allowing for model uncertainty analysis and more rigorous validation.
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17
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Genotoxicity of hydroquinone in A549 cells. Cell Biol Toxicol 2013; 29:213-27. [DOI: 10.1007/s10565-013-9247-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 05/20/2013] [Indexed: 11/25/2022]
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18
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Djurhuus R, Nossum V, Øvrebø S, Skaug V. Proposal on limits for chemical exposure in saturation divers' working atmosphere: the case of benzene. Crit Rev Toxicol 2012; 42:211-29. [PMID: 22304480 DOI: 10.3109/10408444.2011.650791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Saturation diving is performed under extreme environmental conditions. The divers are confined to a limited space for several weeks under high environmental pressure and elevated oxygen partial pressure. At present, divers are protected against chemical exposure by standard exposure limits only adjusted for the increased exposure length, i.e. from 8 to 24 hours a day and from 5 to 7 days a week. The objective of the present study was to indicate a procedure for derivation of occupational exposure limits for saturation diving, termed hyperbaric exposure limits (HEL). Using benzene as an example, a procedure is described that includes identification of the latest key documents, extensive literature search with defined exclusion criteria for the literature retrieved. Hematotoxicity and leukemia were defined as the critical effects, and exposure limits based upon concentration and cumulative exposure data and corresponding risks of leukemia were calculated. Possible interactions of high pressure, elevated pO₂, and continuous exposure have been assessed, and incorporated in a final suggestion of a HEL for benzene. The procedure should be applicable for other relevant chemicals in the divers' breathing atmosphere. It is emphasized that the lack of interactions from pressure and oxygen indicated for benzene may be completely different for other chemicals.
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Affiliation(s)
- Rune Djurhuus
- Norwegian Underwater Intervention AS (NUI AS), Bergen, Norway.
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19
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McHale CM, Zhang L, Smith MT. Current understanding of the mechanism of benzene-induced leukemia in humans: implications for risk assessment. Carcinogenesis 2012; 33:240-52. [PMID: 22166497 PMCID: PMC3271273 DOI: 10.1093/carcin/bgr297] [Citation(s) in RCA: 207] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 11/21/2011] [Accepted: 12/07/2011] [Indexed: 01/01/2023] Open
Abstract
Benzene causes acute myeloid leukemia and probably other hematological malignancies. As benzene also causes hematotoxicity even in workers exposed to levels below the US permissible occupational exposure limit of 1 part per million, further assessment of the health risks associated with its exposure, particularly at low levels, is needed. Here, we describe the probable mechanism by which benzene induces leukemia involving the targeting of critical genes and pathways through the induction of genetic, chromosomal or epigenetic abnormalities and genomic instability, in a hematopoietic stem cell (HSC); stromal cell dysregulation; apoptosis of HSCs and stromal cells and altered proliferation and differentiation of HSCs. These effects modulated by benzene-induced oxidative stress, aryl hydrocarbon receptor dysregulation and reduced immunosurveillance, lead to the generation of leukemic stem cells and subsequent clonal evolution to leukemia. A mode of action (MOA) approach to the risk assessment of benzene was recently proposed. This approach is limited, however, by the challenges of defining a simple stochastic MOA of benzene-induced leukemogenesis and of identifying relevant and quantifiable parameters associated with potential key events. An alternative risk assessment approach is the application of toxicogenomics and systems biology in human populations, animals and in vitro models of the HSC stem cell niche, exposed to a range of levels of benzene. These approaches will inform our understanding of the mechanisms of benzene toxicity and identify additional biomarkers of exposure, early effect and susceptibility useful for risk assessment.
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Affiliation(s)
| | | | - Martyn T. Smith
- Division of Environmental Health Sciences, Genes and Environment Laboratory, School of Public Health, University of California, Berkeley, CA 94720-7356, USA
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20
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The aromatic volatile organic compounds toluene, benzene and styrene induce COX-2 and prostaglandins in human lung epithelial cells via oxidative stress and p38 MAPK activation. Toxicology 2011; 289:28-37. [DOI: 10.1016/j.tox.2011.07.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 07/08/2011] [Accepted: 07/11/2011] [Indexed: 11/22/2022]
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21
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Evaluation of exposure biomarkers in offshore workers exposed to low benzene and toluene concentrations. Int Arch Occup Environ Health 2011; 85:261-71. [DOI: 10.1007/s00420-011-0664-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 06/01/2011] [Indexed: 10/18/2022]
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