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Vermeulen R, Lan Q, Qu Q, Linet MS, Zhang L, Li G, Portengen L, Vlaanderen J, Sungkyoon K, Hayes RB, Yin S, Smith MT, Rappaport SM, Rothman N. Nonlinear low dose hematotoxicity of benzene; a pooled analyses of two studies among Chinese exposed workers. ENVIRONMENT INTERNATIONAL 2023; 177:108007. [PMID: 37290291 DOI: 10.1016/j.envint.2023.108007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/23/2023] [Accepted: 05/29/2023] [Indexed: 06/10/2023]
Abstract
BACKGROUND Impairment of the hematopoietic system is one of the primary adverse health effects from exposure to benzene. We previously have shown that exposure to benzene at low levels (<1 ppm) affects the blood forming system and that these effects were proportionally stronger at lower versus higher levels of benzene exposure. This observation is potentially explained by saturation of enzymatic systems. METHODS Here we extend these analyses by detailed modeling of the exposure response association of benzene and its major metabolites (i.e. catechol, muconic acid, phenol, and hydroquinone) on peripheral white blood cell (WBC) counts and its major cell-subtypes (i.e. granulocytes, lymphocytes, and monocytes) using two previously published cross-sectional studies among occupationally exposed Chinese workers. RESULTS Supra-linear exposure response associations were observed between air benzene concentrations (range ∼ 0.1 - 100 ppm) and WBC counts and its cell-subtypes, with a larger than proportional decrease in cell counts at lower than at higher levels of benzene exposure. The hematotoxicity associations were largely similar in shape when the analyses were repeated with benzene urinary metabolites suggesting that enzymatic saturation is not a full explanation of the observed non-linearity with WBC endpoints. DISCUSSION We hypothesize that the flattening of the exposure response curve especially at higher benzene exposure levels may reflect a response by the bone marrow to maintain hematopoietic homeostasis. Toxicity to the bone marrow and an induced hyper-proliferative response could both contribute to risk of subsequently developing a hematopoietic malignancy. Additional work is needed to explore this hypothesis.
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Affiliation(s)
- Roel Vermeulen
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
| | - Qing Lan
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Bethesda, MD 20892, United States
| | - Qingshan Qu
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY, United States
| | - Martha S Linet
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Bethesda, MD 20892, United States
| | - Luoping Zhang
- School of Public Health, University of California, Berkeley, CA 94720, United States
| | - Guilan Li
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Lutzen Portengen
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
| | - Jelle Vlaanderen
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
| | - Kim Sungkyoon
- School of Public Health, Seoul National University, Seoul, Republic of Korea
| | | | - Songnian Yin
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, CA 94720, United States
| | - Stephen M Rappaport
- School of Public Health, University of California, Berkeley, CA 94720, United States
| | - Nathaniel Rothman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Bethesda, MD 20892, United States
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Schnatter AR, Rooseboom M, Kocabas NA, North CM, Dalzell A, Twisk J, Faulhammer F, Rushton E, Boogaard PJ, Ostapenkaite V, Williams SD. Derivation of an occupational exposure limit for benzene using epidemiological study quality assessment tools. Toxicol Lett 2020; 334:117-144. [PMID: 32497562 DOI: 10.1016/j.toxlet.2020.05.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/20/2020] [Accepted: 05/28/2020] [Indexed: 02/04/2023]
Abstract
This paper derives an occupational exposure limit for benzene using quality assessed data. Seventy-seven genotoxicity and 36 haematotoxicity studies in workers were scored for study quality with an adapted tool based on that of Vlaanderen et al., 2008 (Environ Health. Perspect. 116 1700-5). These endpoints were selected as they are the most sensitive and relevant to the proposed mode of action (MOA) and protecting against these will protect against benzene carcinogenicity. Lowest and No- Adverse Effect Concentrations (LOAECs and NOAECs) were derived from the highest quality studies (i.e. those ranked in the top tertile or top half) and further assessed as being "more certain" or "less certain". Several sensitivity analyses were conducted to assess whether alternative "high quality" constructs affected conclusions. The lowest haematotoxicity LOAECs showed effects near 2 ppm (8 h TWA), and no effects at 0.59 ppm. For genotoxicity, studies also showed effects near 2 ppm and showed no effects at about 0.69 ppm. Several sensitivity analyses supported these observations. These data define a benzene LOAEC of 2 ppm (8 h TWA) and a NOAEC of 0.5 ppm (8 h TWA). Allowing for possible subclinical effects in bone marrow not apparent in studies of peripheral blood endpoints, an OEL of 0.25 ppm (8 h TWA) is proposed.
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Affiliation(s)
| | | | | | - Colin M North
- ExxonMobil Biomedical Sciences, Inc, Annandale, NJ, USA
| | | | - Johannes Twisk
- Dow Chemical International Pvt. Ltd, Terneuzen, the Netherlands
| | | | - Erik Rushton
- Basell Service Company B.V., Rotterdam, the Netherlands
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Nourozi MA, Neghab M, Bazzaz JT, Nejat S, Mansoori Y, Shahtaheri SJ. Association between polymorphism of GSTP1, GSTT1, GSTM1 and CYP2E1 genes and susceptibility to benzene-induced hematotoxicity. Arch Toxicol 2017; 92:1983-1990. [PMID: 29204680 PMCID: PMC6002464 DOI: 10.1007/s00204-017-2104-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 10/24/2017] [Indexed: 11/24/2022]
Abstract
Occupational exposure to benzene has been associated with leukemia, anemia, leukopenia, and thrombocytopenia. Genetic susceptibility to benzene toxicity in humans may be related to variations in benzene metabolizing genes. The main objective of this study was to ascertain whether polymorphism of GSTP1, GSTM1, GSTT1 and CYP2E1 genes might influence susceptibility to the adverse effects of benzene among employees of a petrochemical plant. In this cross-sectional study, 124 employees of a petrochemical plant who had been occupationally exposed to benzene and had one or more abnormal hematological parameter (cases) and 184 subjects with a similar exposure scenario, free from any abnormal hematological parameters (referent) were studied. Atmospheric concentrations of benzene were measured and GSTM1 and GSTT1 genotypes were evaluated using the multiplex polymerase chain reaction (PCR) technique. Additionally, GSTP1 and CYP2E1 genotypes were determined by PCR- restriction fragment length polymorphism (PCR–RFLP). The frequency of null GSTT1 genotype in cases was significantly higher than that of referent group (32.3 vs. 18.5%, OR 2.1, 95% CI 1.23–3.56, p = 0.004). The mean value of platelets in subjects with null GSTT1 genotype was significantly lower than that of individuals with positive GSTT1 genotype (p = 0.015). Conversely, the mean value of leukocytes was significantly higher in subjects with null GSTM1 genotype as compared to those with positive GSTM1 genotype (p = 0.026). Logistic regression analysis showed that, subjects with null GSTT1 genotype had a significantly higher risk for hematological disorders, as compared to those with positive GSTT1 genotype (OR 2.1, 95% CI 1.23–3.56). Moreover, subjects with both null GSTT1 and GSTM1 genotypes had a significantly higher risk for hematological disorders as compared to subjects with positive GSTT1 and GSTM1 genotypes (OR 2.35, 95% CI 1.14–4.8). The results of this study showed that, individuals carrying null GSTT1 or both null STT1 and GSTM1 genotypes had a higher risk and were more susceptible to benzene-induced hematological disorders.
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Affiliation(s)
- Mohamad Amin Nourozi
- Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Masoud Neghab
- Department of Occupational Health Engineering, Research Center for Health Sciences, Institute of Health, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Javad Tavakkoly Bazzaz
- Department of Medical Genetics, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Saharnaz Nejat
- Department of Epidemiology and Biostatistics, School of Public Health, Knowledge Utilization Research Center (KURC), Tehran University of Medical Sciences, Tehran, Iran
| | - Yaser Mansoori
- Non-communicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Seyed Jamaleddin Shahtaheri
- Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
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4
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Doherty BT, Kwok RK, Curry MD, Ekenga C, Chambers D, Sandler DP, Engel LS. Associations between blood BTEXS concentrations and hematologic parameters among adult residents of the U.S. Gulf States. ENVIRONMENTAL RESEARCH 2017; 156:579-587. [PMID: 28448810 PMCID: PMC5687063 DOI: 10.1016/j.envres.2017.03.048] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/28/2017] [Accepted: 03/29/2017] [Indexed: 05/26/2023]
Abstract
BACKGROUND Studies of workers exposed to benzene at average air concentrations below one part per million suggest that benzene, a known hematotoxin, causes hematopoietic damage even at low exposure levels. However, evidence of such effects outside of occupational settings and for other volatile organic compounds (VOCs) is limited. OBJECTIVE To investigate associations between ambient exposures to five VOCs, including benzene, and hematologic parameters among adult residents of the U.S. Gulf Coast. MATERIALS AND METHODS Blood concentrations of selected VOCs were measured in a sample of adult participants in the Gulf Long-term Follow-up Study (GuLF STUDY) during 2012 and 2013. Complete blood counts with differentials were also performed on a subset of participants (n=406). We used these data together with detailed questionnaire data to estimate adjusted associations between blood BTEXS (benzene, toluene, ethylbenzene, o-xylene, m/p-xylene, and styrene) concentrations and hematologic parameters using generalized linear models. RESULTS We observed inverse associations between blood benzene concentrations and hemoglobin concentration and mean corpuscular hemoglobin concentration, and a positive association with red cell distribution width among tobacco smoke-unexposed participants (n=146). Among tobacco smoke-exposed participants (n=247), we observed positive associations between blood VOC concentrations and several hematologic parameters, including increased white blood cell and platelet counts, suggestive of hematopoietic stimulation typically associated with tobacco smoke exposure. Most associations were stronger for benzene than for the other VOCs. CONCLUSIONS Our results suggest that ambient exposure to BTEXS, particularly benzene, may be associated with hematologic effects, including decreased hemoglobin concentration, mean corpuscular hemoglobin concentration, and increased red cell distribution width.
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Affiliation(s)
- Brett T Doherty
- Department of Epidemiology, University of North Carolina at Chapel Hill,135 Dauer Drive, 2101 McGavran-Greenberg Hall, CB #7435, Chapel Hill, NC 27599, USA; National Institute of Environmental Health Sciences, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Richard K Kwok
- National Institute of Environmental Health Sciences, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Matthew D Curry
- Social and Scientific Systems, Inc., 1009 Slater Road, Suite #120, Durham, NC 27703, USA
| | - Christine Ekenga
- Brown School, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - David Chambers
- National Center for Environmental Health, Centers for Disease Control and Prevention,1600 Clifton Road, Atlanta, GA 30329, USA
| | - Dale P Sandler
- National Institute of Environmental Health Sciences, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Lawrence S Engel
- Department of Epidemiology, University of North Carolina at Chapel Hill,135 Dauer Drive, 2101 McGavran-Greenberg Hall, CB #7435, Chapel Hill, NC 27599, USA; National Institute of Environmental Health Sciences, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA.
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5
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De Palma G, Manno M. Metabolic polymorphisms and biomarkers of effect in the biomonitoring of occupational exposure to low-levels of benzene: state of the art. Toxicol Lett 2014; 231:194-204. [PMID: 25447454 DOI: 10.1016/j.toxlet.2014.10.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/07/2014] [Accepted: 10/09/2014] [Indexed: 12/21/2022]
Abstract
Current levels of occupational exposure to benzene, a genotoxic human carcinogen, in Western countries are reduced by two-three orders of magnitude (from ppm to ppb) as compared to the past. However, as benzene toxicity is strongly dependent on biotransformation and recent evidence underlines a higher efficiency of bio-activation pathways at lower levels of exposure, toxic effects at low doses could be higher than expected, particularly in susceptible individuals. Currently, biological monitoring can allow accurate exposure assessment, relying on sensitive and specific enough biomarkers of internal dose. The availability of similarly reliable biomarkers of early effect or susceptibility could greatly improve the risk assessment process to such an extent that risk could even be assessed at the individual level. As to susceptibility biomarkers, functional genetic polymorphisms of relevant biotransformation enzymes may modulate the risk of adverse effects (NQO1) and the levels of biomarkers of internal dose, in particular S-phenylmercapturic acid (GSTM1, GSTT1, GSTA1). Among biomarkers of early effect, genotoxicity indicators, although sensitive in some cases, are too aspecific for routine use in occupational health surveillance programmes. Currently only the periodical blood cell count seems suitable enough to be applied in the longitudinal monitoring of effects from benzene exposure. Novel biomarkers of early effect are expected from higher collaboration among toxicologists and clinicians, also using advanced "omics" techniques.
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Affiliation(s)
- G De Palma
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Section of Public Health and Human Sciences, University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia, Italy.
| | - M Manno
- Department of Public Health, Section of Occupational Medicine and Toxicology, University of Napoli Federico II, Via S. Pansini, 5, 80131 Napoli, Italy
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6
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Arnold SM, Angerer J, Boogaard PJ, Hughes MF, O'Lone RB, Robison SH, Schnatter AR. The use of biomonitoring data in exposure and human health risk assessment: benzene case study. Crit Rev Toxicol 2013; 43:119-53. [PMID: 23346981 PMCID: PMC3585443 DOI: 10.3109/10408444.2012.756455] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/30/2012] [Accepted: 12/04/2012] [Indexed: 01/08/2023]
Abstract
Abstract A framework of "Common Criteria" (i.e. a series of questions) has been developed to inform the use and evaluation of biomonitoring data in the context of human exposure and risk assessment. The data-rich chemical benzene was selected for use in a case study to assess whether refinement of the Common Criteria framework was necessary, and to gain additional perspective on approaches for integrating biomonitoring data into a risk-based context. The available data for benzene satisfied most of the Common Criteria and allowed for a risk-based evaluation of the benzene biomonitoring data. In general, biomarker (blood benzene, urinary benzene and urinary S-phenylmercapturic acid) central tendency (i.e. mean, median and geometric mean) concentrations for non-smokers are at or below the predicted blood or urine concentrations that would correspond to exposure at the US Environmental Protection Agency reference concentration (30 µg/m(3)), but greater than blood or urine concentrations relating to the air concentration at the 1 × 10(-5) excess cancer risk (2.9 µg/m(3)). Smokers clearly have higher levels of benzene exposure, and biomarker levels of benzene for non-smokers are generally consistent with ambient air monitoring results. While some biomarkers of benzene are specific indicators of exposure, the interpretation of benzene biomonitoring levels in a health-risk context are complicated by issues associated with short half-lives and gaps in knowledge regarding the relationship between the biomarkers and subsequent toxic effects.
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7
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Takahashi M, Tsujimura N, Yoshino T, Hosokawa M, Otsuka K, Matsunaga T, Nakasono S. Assessment of benzene-induced hematotoxicity using a human-like hematopoietic lineage in NOD/Shi-scid/IL-2Rγnull mice. PLoS One 2012; 7:e50448. [PMID: 23226520 PMCID: PMC3513313 DOI: 10.1371/journal.pone.0050448] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 10/22/2012] [Indexed: 12/03/2022] Open
Abstract
Despite recent advancements, it is still difficult to evaluate in vivo responses to toxicants in humans. Development of a system that can mimic the in vivo responses of human cells will enable more accurate health risk assessments. A surrogate human hematopoietic lineage can be established in NOD/Shi-scid/IL-2Rγnull (NOG) mice by transplanting human hematopoietic stem/progenitor cells (Hu-NOG mice). Here, we first evaluated the toxic response of human-like hematopoietic lineage in NOG mice to a representative toxic agent, benzene. Flow cytometric analysis showed that benzene caused a significant decrease in the number of human hematopoietic stem/progenitor cells in the bone marrow and the number of human leukocytes in the peripheral blood and hematopoietic organs. Next, we established chimeric mice by transplanting C57BL/6 mouse-derived bone marrow cells into NOG mice (Mo-NOG mice). A comparison of the degree of benzene-induced hematotoxicity in donor-derived hematopoietic lineage cells within Mo-NOG mice indicated that the toxic response of Hu-NOG mice reflected interspecies differences in susceptibilities to benzene. Responses to the toxic effects of benzene were greater in lymphoid cells than in myeloid cells in Mo-NOG and Hu-NOG mice. These findings suggested that Hu-NOG mice may be a powerful in vivo tool for assessing hematotoxicity in humans, while accounting for interspecies differences.
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Affiliation(s)
- Masayuki Takahashi
- Biological Environment Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Chiba, Japan
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8
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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: 205] [Impact Index Per Article: 17.1] [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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9
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Low level occupational benzene exposure and hematological parameters. Chem Biol Interact 2010; 184:94-100. [DOI: 10.1016/j.cbi.2010.01.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 12/23/2009] [Accepted: 01/05/2010] [Indexed: 11/17/2022]
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10
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Impact of organic solvents and environmental pollutants on the physiological function in petrol filling workers. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2009; 5:139-46. [PMID: 19139531 PMCID: PMC3699983 DOI: 10.3390/ijerph5030139] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Long term exposure to solvents and air pollutants can lead to deleterious effects on respiratory, haematological and thyroid functioning. The aim of this study was to investigate whether chronic exposure to solvents like benzene and pollutants like carbon monoxide in petrol filling workers had adverse effect on blood parameters, thyroid and respiratory functions. The study group consisted of 42 healthy, non-smoker petrol filling workers, aged 20–50 years with work (exposure) duration from 2–15 years while 36 healthy subjects of the same age group served as controls. Physical examination and measurement of pulmonary functions by portable electronic spirometer were performed. Complete blood pictures (CBP) were determined by normal haematology lab procedure and hormones by Chemiluminescence immunoassay (CLIA) light absorption techniques. There was a significant decrease in the lung volumes and capacities; the restrictive pattern was more prevalent in the workers when compared with the control groups. But in the workers exposed for long period (more than 10 years) the restrictive pattern was changed to mixed pattern. A significant increase in haemoglobin (Hb) (>16 mg %) and red blood cells (RBC) (5.4 million cells/mm3) were observed in workers with longer period of exposure when compared with the control subjects (14.483 mg% and 4.83 million cells/mm3 for Hb and RBC respectively). White blood cell count except eosinophils and platelets were significantly lower in workers compared to controls. Marked increase in the tetra iodothyroinine (T4), free thyroxine (T4F) level and significant decrease in thyroid stimulating hormones (TSH), and tri-iodothyronine (T3) were observed between long term exposed and non – exposed groups. Till now researchers focused only on the effect of solvents in workers professionally exposed to solvents without considering the effect of concomittant air pollution. The result obtained from present study indicates that there is a significant toxic effect of solvents and air pollutants on workers exposed for longer duration. Improved detection and prevention technologies are needed to answer environmentally related health questions for petrol filling workers.
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Wilbur S, Wohlers D, Paikoff S, Keith LS, Faroon O. ATSDR evaluation of health effects of benzene and relevance to public health. Toxicol Ind Health 2009; 24:263-398. [PMID: 19022880 DOI: 10.1177/0748233708090910] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
As part of its mandate, the Agency for Toxic Substances and Disease Registry (ATSDR) prepares toxicological profiles on hazardous chemicals found at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) National Priorities List (NPL) sites that have the greatest public health impact. These profiles comprehensively summarize toxicological and environmental information. This article constitutes the release of portions of the Toxicological Profile for Benzene. The primary purpose of this article is to provide public health officials, physicians, toxicologists, and other interested individuals and groups with an overall perspective on the toxicology of benzene. It contains descriptions and evaluations of toxicological studies and epidemiological investigations and provides conclusions, where possible, on the relevance of toxicity and toxicokinetic data to public health.
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Affiliation(s)
- S Wilbur
- Agency for Toxic Substances and Disease Registry (ATSDR), U.S. Department of Health and Human Services, Atlanta, Georgia 30333, USA.
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12
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He Y, Liang Y, Fu H. Application of bayesian methods to exposure assessment of area concentrations at a rubber factory. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2009; 6:622-34. [PMID: 19440405 PMCID: PMC2672369 DOI: 10.3390/ijerph6020622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Accepted: 02/05/2009] [Indexed: 11/26/2022]
Abstract
The present study estimated area concentrations of airborne benzene in several workshops using Bayesian methods based on available historical measurements. A rubber products factory utilizing benzene was investigated. Historical measurements of benzene concentrations, expert experiences, and deterministic modeling were utilized in a Bayesian Method to estimate area concentrations. Historical concentrations (n=124) were available with the geometric mean of 15.3 mg/m(3). The geometric mean of the current field measurements on the workstations ranged from 0.7 to 89.0 mg/m(3). One of the seven historical geometric means by work locations significantly differed from the field measurements for equivalent locations, but none of the geometric means of Bayesian estimates were significantly different from the field measurement results. The Bayesian methods based on the historical measurements appeared to be a useful tool for more closely estimating area concentrations shown by field data than that predicted only using historical measurements.
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Affiliation(s)
| | | | - Hua Fu
- School of Public Health, Fudan University /Box 288, No 130, Dong’an Road, Shanghai 200032, PR China
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13
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Abstract
A large population of humans is exposed to benzene from various occupational and environmental sources. Benzene is an established human and animal carcinogen. Exposure to benzene has been associated with leukaemia in humans and several types of malignancies in animals. The exact mechanism of benzene-induced toxicity is poorly understood. It is believed that benzene exerts its adverse effects by metabolic activation to toxic metabolites. Certain benzene metabolites are genotoxic and mutagenic. This consolidated short-review is composed of human and animal studies to summarize the adverse effects of benzene with special reference to molecular mechanisms involved in benzene-induced toxicity.
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Affiliation(s)
- Haseeb Ahmad Khan
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia.
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14
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Lan Q, Zhang L, Li G, Vermeulen R, Weinberg RS, Dosemeci M, Rappaport SM, Shen M, Alter BP, Wu Y, Kopp W, Waidyanatha S, Rabkin C, Guo W, Chanock S, Hayes RB, Linet M, Kim S, Yin S, Rothman N, Smith MT. Hematotoxicity in workers exposed to low levels of benzene. Science 2004; 306:1774-6. [PMID: 15576619 PMCID: PMC1256034 DOI: 10.1126/science.1102443] [Citation(s) in RCA: 406] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Benzene is known to have toxic effects on the blood and bone marrow, but its impact at levels below the U.S. occupational standard of 1 part per million (ppm) remains uncertain. In a study of 250 workers exposed to benzene, white blood cell and platelet counts were significantly lower than in 140 controls, even for exposure below 1 ppm in air. Progenitor cell colony formation significantly declined with increasing benzene exposure and was more sensitive to the effects of benzene than was the number of mature blood cells. Two genetic variants in key metabolizing enzymes, myeloperoxidase and NAD(P)H:quinone oxidoreductase, influenced susceptibility to benzene hematotoxicity. Thus, hematotoxicity from exposure to benzene occurred at air levels of 1 ppm or less and may be particularly evident among genetically susceptible subpopulations.
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Affiliation(s)
- Qing Lan
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Luoping Zhang
- School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Guilan Li
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Roel Vermeulen
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Rona S. Weinberg
- New York Blood Center, Clinical Services, White Plains, NY 10605, USA
| | - Mustafa Dosemeci
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Stephen M. Rappaport
- School of Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Min Shen
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Blanche P. Alter
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Yongji Wu
- Peking Union Medical College, Beijing, China
| | | | - Suramya Waidyanatha
- School of Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Charles Rabkin
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Weihong Guo
- School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Stephen Chanock
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
- Center for Cancer Research, NCI, NIH, DHHS, Bethesda, MD 20892, USA
| | - Richard B. Hayes
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Martha Linet
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Sungkyoon Kim
- School of Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Songnian Yin
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Nathaniel Rothman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA
| | - Martyn T. Smith
- School of Public Health, University of California, Berkeley, CA 94720, USA
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15
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Tsai SP, Fox EE, Ransdell JD, Wendt JK, Waddell LC, Donnelly RP. A hematology surveillance study of petrochemical workers exposed to benzene. Regul Toxicol Pharmacol 2004; 40:67-73. [PMID: 15265607 DOI: 10.1016/j.yrtph.2004.05.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Indexed: 10/26/2022]
Abstract
Historically, complete blood counts (CBCs) have been recognized as an easy and readily available screen for hematotoxicity following occupational exposure to benzene. The purpose of this study is to evaluate hematology data from employees who have ever participated in the Shell Benzene Medical Surveillance Program (BMSP) compared to employees who have not participated and to examine the sensitivity of CBCs to detect hematological changes in a low-exposure occupational setting. This large study included 1200 employees who participated in the BMSP, with mean benzene exposure (TWA-8) of 0.60 ppm from 1977 to 1988 and 0.14 ppm since 1988, and 3227 comparison employees. The comparison group included employees not enrolled in either the benzene or butadiene surveillance programs. Abnormality of six CBC parameters and the adjusted mean values of these parameters in the exposed group were compared with that of the comparison group. We found no increased abnormality for any hematology parameter among exposed employees. The adjusted mean values (adjusted for age, sex, race, length of time between first and last exam, and current smoking status) of the exposed employees were similar to those in the comparison group. At current occupational exposure levels for benzene, no evidence of adverse hematological effects was observed in this study. These results raise the question of whether annual CBC surveillance for benzene-exposed workers has adequate sensitivity to detect meaningful hematological changes due to low-level exposures.
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Affiliation(s)
- Shan P Tsai
- Shell Oil Company, Shell Health Services, One Shell Plaza, P.O. Box 2463, Houston, TX 77252-2463, USA.
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16
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Bogadi-Sare A, Zavalić M, Turk R. Utility of a routine medical surveillance program with benzene exposed workers. Am J Ind Med 2003; 44:467-73. [PMID: 14571510 DOI: 10.1002/ajim.10296] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND A medical surveillance program of benzene-exposed workers has to be established in such a way as to observe early signs of benzene-induced cytopenia, pancytopenia, or leukemia. This study evaluates the utility of routine medical survey applied to benzene-exposed workers by analyzing the hematological, immunological, and cytogenetic assay results. METHODS The results of a previous study of hematological, immunological, and cytogenetic assays in benzene-exposed workers (up to 15 ppm) are used to discuss medical surveillance program by defining the relationship between various benzene exposure concentrations and toxic endpoints. RESULTS Exposure to benzene concentration lower than 5 ppm does not produce any abnormal hematological measurements. For benzene cumulative exposure above 100 (ppm-years), some blood indices [mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), band neutrophils] show significant differences in comparison to the control group. The incidence of dicentric chromosomes was higher and the level of B-lymphocytes was lower even with workers exposed to 5 ppm of benzene; correlation with exposure indicators was not found. CONCLUSIONS The results suggest that peripheral blood indices, although not sensitive enough, are still the most suitable parameters in a health surveillance program applied to benzene-exposed workers. B-lymphocytes could be a promising indicator of the benzene-induced damage. Cytogenetic tests did not prove to be suitable. Further investigation of useful screening tests for health surveillance program of benzene-exposed workers is still required.
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Affiliation(s)
- Ana Bogadi-Sare
- Croatian Institute of Occupational Health, Division for Occupational Diseases and Industrial Toxicology, Zagreb, Croatia.
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17
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Albertini R, Clewell H, Himmelstein MW, Morinello E, Olin S, Preston J, Scarano L, Smith MT, Swenberg J, Tice R, Travis C. The use of non-tumor data in cancer risk assessment: reflections on butadiene, vinyl chloride, and benzene. Regul Toxicol Pharmacol 2003; 37:105-32. [PMID: 12662914 DOI: 10.1016/s0273-2300(02)00019-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The estimation and characterization of a cancer risk is grounded in the observation of tumors in humans and/or experimental animals. Increasingly, however, other kinds of data (non-tumor data) are finding application in cancer risk assessment. Metabolism and kinetics, adduct formation, genetic damage, mode of action, and biomarkers of exposure, susceptibility, and effects are examples. While these and other parameters have been studied for many important chemicals over the past 30-40 years, their use in risk assessments is more recent, and new insights and opportunities are continuing to unfold. To provide some perspective on this field, the ILSI Risk Science Institute asked a select working group to characterize the pertinent non-tumor data available for 1,3-butadiene, benzene, and vinyl chloride and to comment on the utility of these data in characterizing cancer risks. This paper presents the findings of that working group and concludes with 15 simple principles for the use of non-tumor data in cancer risk assessment.
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18
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Khuder SA, Youngdale MC, Bisesi MS, Schaub EA. Assessment of complete blood count variations among workers exposed to low levels of benzene. J Occup Environ Med 1999; 41:821-6. [PMID: 10491799 DOI: 10.1097/00043764-199909000-00015] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The effect of benzene on white blood cell and red blood cell counts, hemoglobin level, mean corpuscular volume (MCV), and platelet count was investigated among workers in a small petroleum company. The investigated cohort consisted of 105 workers exposed to low levels of benzene between 1967 and 1994. The average level of benzene exposure per year ranged between 0.14 parts per million and 2.08 parts per million (8-hour time-weighted average). The mean complete blood count (CBC) demonstrated values within normal ranges. With the exception of white blood cells, all other CBC values were significantly reduced during the follow-up period. Length of employment was significantly related to the changes in MCV and platelet counts. The reductions in MCV were significant only among workers who had been employed for more than 10 years at this particular company. The findings of this study suggest that low levels of benzene may affect CBC values. CBC values may serve as a useful tool for biological monitoring for workers with low-level benzene exposure.
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Affiliation(s)
- S A Khuder
- Department of Medicine, Medical College of Ohio, Toledo 43699-0008, USA
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