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MGMT in glial carcinogenesis. Roles from prevention to treatment. Eur J Cancer Prev 2022; 31:568-576. [DOI: 10.1097/cej.0000000000000746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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DeBono N, Kelly-Reif K, Richardson D, Keil A, Robinson W, Troester M, Marshall S. Mortality among autoworkers manufacturing electronics in Huntsville, Alabama. Am J Ind Med 2019; 62:282-295. [PMID: 30569473 DOI: 10.1002/ajim.22933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND Workers raised concerns over suspected excesses of mortality at automotive electronics manufacturing facilities in Huntsville, Alabama. METHODS A study of 4396 UAW members ever-employed at Huntsville facilities between 1972 and 1993 was conducted with mortality follow-up through 2016. Standardized Mortality Ratios (SMRs) were estimated using U.S. and Alabama reference rates. RESULTS Relative to U.S. rates, there was a modest excess of all-cause mortality among White female workers (SMR 1.08, 95%CI: 0.99-1.18) and among all workers hired <1977 at the original plant building (SMR 1.10, 95%CI: 0.99-1.22). There was excess nervous system disorder (SMR 1.24, 95%CI: 0.91-1.65) and brain and nervous system cancer (SMR 1.31, 95%CI: 0.67-2.28) mortality. Estimates for several causes of interest were imprecise. CONCLUSIONS All-cause mortality estimates were greater than anticipated based on results from other UAW cohorts. The excess of nervous system disease mortality is consistent with other studies of electronics workers exposed to lead-solder and chlorinated solvents.
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Affiliation(s)
- Nathan DeBono
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Kaitlin Kelly-Reif
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - David Richardson
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Alex Keil
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Whitney Robinson
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Melissa Troester
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Stephen Marshall
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
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DeBono N, Richardson D, Keil A, Kelly-Reif K, Robinson W, Troester M, Marshall S. Employment characteristics and cause-specific mortality at automotive electronics manufacturing plants in Huntsville, Alabama. Am J Ind Med 2019; 62:296-308. [PMID: 30791109 DOI: 10.1002/ajim.22963] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Revised: 01/25/2019] [Accepted: 02/01/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND This study was carried out in response to worker concerns over their exposure to lead solder and chlorinated solvents at automotive electronics manufacturing plants in Huntsville, Alabama. METHODS A study of 4396 United Autoworkers members ever-employed at the plants between 1972 and 1993 was conducted with mortality follow-up through 2016. Poisson regression was used to estimate mortality rate ratios (RR) according to employment characteristics, including calendar period of employment. RESULTS Pre-1977 hires exhibited elevated adjusted rates of all-cause (RR, 1.29; 95% confidence interval [CI], 1.09-1.52), cardiovascular (RR, 1.38; 95% CI, 1.03-1.86), and digestive system (RR, 2.31; 95% CI, 1.04-5.10) disease mortality relative to the most recent hire group (1984-1993). Never- versus ever-employment in a skilled trade job was associated with elevated adjusted rates of all-cause, all-cancer, and cardiovascular disease mortality. Nervous system disorder mortality was greatest among 1977-1983 hires. CONCLUSIONS Elevated mortality among pre-1977 hires is consistent with worker concerns over greater exposure to hazards at the original plant building.
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Affiliation(s)
- Nathan DeBono
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - David Richardson
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Alex Keil
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Kaitlin Kelly-Reif
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Whitney Robinson
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Melissa Troester
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Stephen Marshall
- Department of Epidemiology; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
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Makris KC, Voniatis M. Brain cancer cluster investigation around a factory emitting dichloromethane. Eur J Public Health 2018; 28:338-343. [PMID: 29036600 DOI: 10.1093/eurpub/ckx170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background The health risks associated with dichloromethane (DCM) for the general population living near industrial activities have not yet been quantified, primarily due to lack of epidemiological datasets. In the absence of such human data, we undertook a cancer cluster investigation in Cyprus around a historically using DCM plant producing shoe soles that were globally exported. We designed the methodology to investigate the possible existence of a cancer cluster in the area around the factory (point zero) and within a radius of 500 meters. Methods A retrospective comparative population study was designed using a group of cancer patients living or working in the chosen geographical area around the factory. Results Mean stack emissions of DCM of 88 mg/Nm3 and flow rates of 850 g/h exceeded the permissible DCM limits established for industrial zones. Brain and central nervous system (CNS) cancer incidence rates showed significant (P < 0.001) increase in the study area around the plant when compared with those observed in other areas of Cyprus. Calculated standardized incidence ratios for brain/CNS after adjusting for the age at diagnosis ranged from 11.3-25.7 [mean 6.5 (3.02 : 12.3)] for the study area. Conclusions We showed the association between chronic, unintentional DCM exposures and brain/CNS cancer cases for the general population located in a residential area being in close proximity with a plant historically emitting DCM.
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Affiliation(s)
- Konstantinos C Makris
- Cyprus International Institute for Environmental and Public Health, Cyprus University of Technology, Limassol, Cyprus
| | - Michael Voniatis
- Ministry of Labour, Welfare and Social Insurance, Nicosia, Cyprus
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Benke G, Turner MC, Fleming S, Figuerola J, Kincl L, Richardson L, Blettner M, Hours M, Krewski D, McLean D, Parent ME, Sadetzki S, Schlaefer K, Schlehofer B, Siemiatycki J, van Tongeren M, Cardis E. Occupational solvent exposure and risk of glioma in the INTEROCC study. Br J Cancer 2017; 117:1246-1254. [PMID: 28910824 PMCID: PMC5674105 DOI: 10.1038/bjc.2017.285] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 07/25/2017] [Accepted: 07/27/2017] [Indexed: 12/23/2022] Open
Abstract
Background: The aetiology of glioma remains largely unknown. Occupational solvent exposure has been suggested as a putative cause of glioma, but past studies have been inconsistent. We examined the association between a range of solvents and glioma risk within the INTEROCC project, a study of brain tumours and occupational exposures based on data from seven national case–control studies conducted in the framework of the INTERPHONE study. We also investigated associations according to tumour grade. Methods: Data from the seven countries were standardised and then combined into one aggregate data set. Pooled odds ratios (ORs) were estimated for adjusted models that included sex, age, country–region of residence and level of educational attainment. Exposures to any solvent or 11 specific solvents or subgroups were assessed using a modified version of the FINJEM job exposure matrix (JEM) specifically developed for the study, called INTEROCC-JEM. Results: Analysis included 2000 glioma cases and 5565 controls. For glioma and ever/never exposure to any solvent, the OR was 0.91 (95% confidence interval: 0.74–1.11). All ORs were <1.0 for specific solvents/subgroups. There were no increases in risk according to high or low grade of tumour. Conclusions: The results of this study show no consistent associations for any solvent exposures overall or by grade of tumour.
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Affiliation(s)
- Geza Benke
- Department of Epidemiology and Preventive Medicine, Monash University, Melbourne 3004, Australia
| | - Michelle C Turner
- Barcelona Institute for Global Health (ISGlobal), Barcelona 08036, Spain.,Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona 08003, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid 028020, Spain.,McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa K1H 8M5, Canada
| | - Sarah Fleming
- Leeds Institute of Cardiovascular and Metabolic Medicine, Institute of Cancer &Pathology, University of Leeds, Leeds LS2 9LN, UK
| | - Jordi Figuerola
- Barcelona Institute for Global Health (ISGlobal), Barcelona 08036, Spain.,Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona 08003, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid 028020, Spain
| | - Laurel Kincl
- Environmental and Occupational Health program in the College of Public Health and Human Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Lesley Richardson
- University of Montreal Hospital Research Centre (CRCHUM), Montreal H2X OA9, Canada
| | - Maria Blettner
- Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Center, Johannes-Gutenberg University Mainz, Mainz 55131, Germany
| | - Martine Hours
- Unité Mixte de Recherche Epidémiologique Transport Travail Environnement Université Lyon 1/IFSTTAR, Université de Lyon, Lyon 69675, France
| | - Daniel Krewski
- McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa K1H 8M5, Canada.,School of Epidemiology, Public Health and Disease Prevention, Faculty of Medicine, University of Ottawa, Ottawa K1G 5Z3, Canada
| | - David McLean
- Centre for Public Health Research, Massey University, Wellington 6140, New Zealand
| | - Marie-Elise Parent
- INRS-Institut Armand-Frappier, Université du Québec, Laval H7V 1B7, Canada
| | - Siegal Sadetzki
- The Cancer &Radiation Epidemiology Unit, The Gertner Institute, Chaim Sheba Medical Center, Tel Hashomer 52620, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Klaus Schlaefer
- German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | | | - Jack Siemiatycki
- University of Montreal Hospital Research Centre (CRCHUM), Montreal H2X OA9, Canada
| | - Martie van Tongeren
- Institute of Occupational Medicine, Edinburgh EH14 4AP, UK.,Centre for Occupational and Environmental Health, Centre for Epidemiology, Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Elisabeth Cardis
- Barcelona Institute for Global Health (ISGlobal), Barcelona 08036, Spain.,Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona 08003, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid 028020, Spain
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McLean D, Fleming S, Turner MC, Kincl L, Richardson L, Benke G, Schlehofer B, Schlaefer K, Parent ME, Hours M, Krewski D, van Tongeren M, Sadetzki S, Siemiatycki J, Cardis E. Occupational solvent exposure and risk of meningioma: results from the INTEROCC multicentre case-control study. Occup Environ Med 2014; 71:253-8. [PMID: 24474387 DOI: 10.1136/oemed-2013-101780] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To examine associations between occupational exposure to selected organic solvents and meningioma. METHODOLOGY A multicentre case-control study conducted in seven countries, including 1906 cases and 5565 controls. Occupational exposure to selected classes of organic solvents (aliphatic and alicyclic hydrocarbons, aromatic hydrocarbons, chlorinated hydrocarbons and 'other' organic solvents) or seven specific solvents (benzene, toluene, trichloroethylene, perchloroethylene, 1,1,1-trichloroethylene, methylene chloride and gasoline) was assessed using lifetime occupational histories and a modified version of the FINJEM job-exposure matrix (INTEROCC-JEM). Study participants were classified as 'exposed' when they had worked in an occupation for at least 1 year, with a 5-year lag, in which the estimated prevalence of exposure was 25% or greater in the INTEROCC-JEM. Associations between meningioma and each of the solvent exposures were estimated using conditional logistic regression, adjusting for potential confounders. RESULTS A total of 6.5% of study participants were ever exposed to 'any' solvent, with a somewhat greater proportion of controls (7%) ever exposed compared with cases (5%), but only one case was ever exposed to any chlorinated hydrocarbon (1,1,1-trichloroethane). No association was observed between any of the organic solvents and meningioma, in either men or women, and no dose-response relationships were observed in internal analyses using either exposure duration or cumulative exposure. DISCUSSION We found no evidence that occupational exposure to these organic solvents is associated with meningioma.
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Affiliation(s)
- Dave McLean
- Centre for Public Health Research, Massey University, Wellington, New Zealand
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Occupational exposure to methylene chloride and risk of cancer: a meta-analysis. Cancer Causes Control 2013; 24:2037-49. [DOI: 10.1007/s10552-013-0283-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 09/02/2013] [Indexed: 10/26/2022]
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9
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Neta G, Stewart PA, Rajaraman P, Hein MJ, Waters MA, Purdue MP, Samanic C, Coble JB, Linet MS, Inskip PD. Occupational exposure to chlorinated solvents and risks of glioma and meningioma in adults. Occup Environ Med 2012; 69:793-801. [PMID: 22864249 PMCID: PMC3850418 DOI: 10.1136/oemed-2012-100742] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES Chlorinated solvents are classified as probable or possible carcinogens. It is unknown whether exposure to these agents increases the risk of malignant or benign brain tumours. Our objective was to evaluate associations of brain tumour risk with occupational exposure to six chlorinated solvents (i.e., dichloromethane, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene and perchloroethylene). METHODS 489 glioma cases, 197 meningioma cases and 799 controls were enrolled in a hospital-based case-control study conducted at three U.S.A. hospitals in Arizona, Massachusetts and Pennsylvania. Information about occupational history was obtained through a detailed inperson interview that included job-specific modules of questions such that the interview was tailored to each individual's particular work history. An industrial hygienist assessed potential solvent exposure based on this information and an exhaustive review of the relevant industrial hygiene literature. Unconditional logistic regression models were used to calculate OR and 95% CI for each solvent for ever/never, duration, cumulative, average weekly and highest exposure. RESULTS Overall, we found no consistent evidence of an increased risk of glioma or meningioma related to occupational exposure to the six chlorinated solvents evaluated. There was some suggestion of an association between carbon tetrachloride and glioma in analyses restricted to exposed subjects, with average weekly exposure above the median associated with increased risk compared with below the median exposure (OR = 7.1, 95% CI 1.1 to 45.2). CONCLUSIONS We found no consistent evidence for increased brain tumour risk related to chlorinated solvents.
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Affiliation(s)
- Gila Neta
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, EPS, Room 7092, 6120 Executive Boulevard, Bethesda, MD 20852-7244, USA.
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11
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Ruder AM, Yiin JH, Waters MA, Carreón T, Hein MJ, Butler MA, Calvert GM, Davis-King KE, Schulte PA, Mandel JS, Morton RF, Reding DJ, Rosenman KD, Stewart PA. The Upper Midwest Health Study: gliomas and occupational exposure to chlorinated solvents. Occup Environ Med 2012; 70:73-80. [PMID: 23104734 DOI: 10.1136/oemed-2011-100588] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Occupational exposure to chlorinated aliphatic solvents has been associated with an increased cancer risk, including brain cancer. However, many of these solvents remain in active, large-volume use. We evaluated glioma risk from non-farm occupational exposure (ever/never and estimated cumulative exposure) to any of the six chlorinated solvents--carbon tetrachloride, chloroform, methylene chloride, trichloroethylene, tetrachloroethylene or 1,1,1--trichloroethane-among 798 cases and 1175 population-based controls, aged 18-80 years and non-metropolitan residents of Iowa, Michigan, Minnesota and Wisconsin. Methods Solvent use was estimated based on occupation, industry and era, using a bibliographic database of published exposure levels and exposure determinants. Unconditional logistic regression was used to calculate ORs adjusted for frequency matching variables age group and sex, and age and education. Additional analyses were limited to 904 participants who donated blood specimens (excluding controls reporting a previous diagnosis of cancer) genotyped for glutathione-S-transferases GSTP1, GSTM3 and GSTT1. Individuals with functional GST genes might convert chlorinated solvents crossing the blood-brain barrier into cytotoxic metabolites. RESULTS Both estimated cumulative exposure (ppm-years) and ever exposure to chlorinated solvents were associated with decreased glioma risk and were statistically significant overall and for women. In analyses comparing participants with a high probability of exposure with the unexposed, no associations were statistically significant. Solvent-exposed participants with functional GST genes were not at increased risk of glioma. CONCLUSIONS We observed no associations of glioma risk and chlorinated solvent exposure. Large pooled studies are needed to explore the interaction of genetic pathways and environmental and occupational exposures in glioma aetiology.
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Affiliation(s)
- Avima M Ruder
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, OH, USA.
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Lupo PJ, Lee LJ, Okcu MF, Bondy ML, Scheurer ME. An exploratory case-only analysis of gene-hazardous air pollutant interactions and the risk of childhood medulloblastoma. Pediatr Blood Cancer 2012; 59:605-10. [PMID: 22389292 PMCID: PMC3371277 DOI: 10.1002/pbc.24105] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 01/17/2012] [Indexed: 11/11/2022]
Abstract
BACKGROUND There is evidence that exposure to chlorinated solvents may be associated with childhood medulloblastoma and primitive neuroectodermal tumor (M/PNET) risk. Animal models suggest genes related to detoxification and DNA repair are important in the carcinogenicity of these pollutants; however, there have been no human studies assessing the modifying effects of these genotypes on the association between chlorinated solvents and childhood M/PNET risk. PROCEDURE We conducted a case-only study to evaluate census tract-level exposure to chlorinated solvents and the risk of childhood M/PNET in the context of detoxification and DNA repair genotypes. Cases (n = 98) were obtained from Texas Children's Hospital and MD Anderson Cancer Center. Key genotypes (n = 22) were selected from the Illumina Human 1M Quad SNP Chip. Exposure to chlorinated solvents (methylene chloride, perchloroethylene, trichloroethylene, and vinyl chloride) was estimated from the US EPA's 1999 Assessment System for Population Exposure Nationwide (ASPEN). Logistic regression was used to estimate the case-only odds ratios and 95% confidence intervals (CIs). RESULTS There were 11 significant gene-environment interactions associated with childhood M/PNET risk. However, after correcting for multiple comparisons, only the interaction between high trichloroethylene levels and OGG1 rs293795 significantly increased the risk of childhood M/PNET risk (OR = 9.24, 95% CI: 2.24, 38.24, Q = 0.04). CONCLUSIONS This study provides an initial assessment of the interaction between ambient levels of chlorinated solvents and potentially relevant genotypes on childhood M/PNET risk. Our results are exploratory and must be validated in animal models, as well as additional human studies.
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Affiliation(s)
- Philip J. Lupo
- Human Genetics Center, Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, TX, USA
| | - Laura J. Lee
- Human Genetics Center, Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, TX, USA
| | - M. Fatih Okcu
- Department of Pediatrics, Texas Children’s Cancer Center, Baylor College of Medicine, Houston, Texas
| | - Melissa L. Bondy
- Department of Pediatrics, Texas Children’s Cancer Center, Baylor College of Medicine, Houston, Texas
| | - Michael E. Scheurer
- Department of Pediatrics, Texas Children’s Cancer Center, Baylor College of Medicine, Houston, Texas,CORRESPONDENCE: Michael E. Scheurer, Ph.D., M.P.H., One Baylor Plaza, MS-BCM305, Houston, TX 77030, Phone: 713-798-5547; Fax: 713-798-8711,
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Nelson JS, Burchfiel CM, Fekedulegn D, Andrew ME. Potential risk factors for incident glioblastoma multiforme: the Honolulu Heart Program and Honolulu-Asia Aging Study. J Neurooncol 2012; 109:315-21. [PMID: 22588335 PMCID: PMC4693293 DOI: 10.1007/s11060-012-0895-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 04/30/2012] [Indexed: 10/28/2022]
Abstract
Glioblastoma multiforme (GBM) is the most common adult primary malignant brain tumor. Ninety percent of adult GBM patients die within 24 months after diagnosis. The etiology of GBM is unknown. The Honolulu Heart Program (HHP) and Honolulu-Asia Aging Study (HAAS) are prospective, cohort studies of cardiovascular and neurodegenerative disease based on 8,006 Japanese-American men followed since 1965. The Japan Hawaii Cancer Study provides data on incident cancer cases in the HHP/HAAS cohort. We used data from these studies to obtain epidemiologic information about GBM. GBM cases were identified by searching the 1965-1998 databases using International Classification of Diseases (ICD-9) codes. Nine histologically confirmed GBM cases, 58-80 years old, were identified. The incidence rate was 6.2/100,000 person-years. Records of each case were reviewed. Selected variables from the first three examinations (1965-1968; 1968-1970; 1971-1974) were used to identify potential candidate GBM risk factors. A multivariate Cox proportional hazards model showed sugar intake and occupational exposure to carbon tetrachloride were independently and significantly associated with development of GBM.
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Cooper GS, Scott CS, Bale AS. Insights from epidemiology into dichloromethane and cancer risk. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2011; 8:3380-98. [PMID: 21909313 PMCID: PMC3166749 DOI: 10.3390/ijerph8083380] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 07/07/2011] [Accepted: 07/13/2011] [Indexed: 11/16/2022]
Abstract
Dichloromethane (methylene chloride) is a widely used chlorinated solvent. We review the available epidemiology studies (five cohort studies, 13 case-control studies, including seven of hematopoietic cancers), focusing on specific cancer sites. There was little indication of an increased risk of lung cancer in the cohort studies (standardized mortality ratios ranging from 0.46 to 1.21). These cohorts are relatively small, and variable effects (e.g., point estimates ranging from 0.5 to 2.0) were seen for the rarer forms of cancers such as brain cancer and specific hematopoietic cancers. Three large population-based case-control studies of incident non-Hodgkin lymphoma in Europe and the United States observed odds ratios between 1.5 and 2.2 with dichloromethane exposure (ever exposed or highest category of exposure), with higher risk seen in specific subsets of disease. More limited indications of associations with brain cancer, breast cancer, and liver and biliary cancer were also seen in this collection of studies. Existing cohort studies, given their size and uneven exposure information, are unlikely to resolve questions of cancer risks and dichloromethane exposure. More promising approaches are population-based case-control studies of incident disease, and the combination of data from such studies, with robust exposure assessments that include detailed occupational information and exposure assignment based on industry-wide surveys or direct exposure measurements.
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Affiliation(s)
- Glinda S Cooper
- National Center for Environmental Assessment, Office of Research and Development, United States Environmental Protection Agency, Washington, DC 20460, USA.
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Kawamoto T, Pham TTP, Matsuda T, Oyama T, Tanaka M, Yu HS, Uchiyama I. Historical review on development of environmental quality standards and guideline values for air pollutants in Japan. Int J Hyg Environ Health 2011; 214:296-304. [PMID: 21680244 DOI: 10.1016/j.ijheh.2011.05.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 04/09/2011] [Accepted: 05/17/2011] [Indexed: 11/30/2022]
Abstract
Environmental quality standards (EQSs) have been established as desirable levels to be maintained for protection of human health and the conservation of the living environment by Basic Environment Law. EQSs in ambient air had been set for 10 substances (sulfur dioxide (SO(2)), carbon monoxide (CO), suspended particulate matter (SPM), nitrogen dioxide (NO(2)) and photochemical oxidants (Ox), benzene, tetrachloroethylene, trichloroethylene, dioxins and dichloromethane) and guideline values for 7 (acrylonitorile, vinyl chloride monomer, mercury, nickel compounds, 1,3-butadiene, chloroform and 1,2-dichloromethane) in Japan by 2009. EQSs for the classical (or traditional) air pollutants, SO(2), CO, SPM, NO(2) and Ox, were set according to the minimal requirement to protect human health, based on evidence from epidemiological studies conducted before the 1970s. In 1996, the Central Environment Council designated substances which may be hazardous air pollutants and substances requiring priority action, and adopted the concept of risk assessment to set EQSs and guideline values. A life-long risk level (virtually safe dose) of 10(-5) was used to set EQS for benzene, and guideline values for vinyl chloride monomer, nickel compounds, and 1,3-butadiene. EQSs for trichloroethylene, tetrachloroethylene and dichloromethane, and guideline values for acrylonitorile and mercury were set using uncertain factors and lowest observed adverse effect (LOAEL)/no observed adverse effect level (NOAEL). The results of animal experiments were utilized to set guideline values for chloroform and 1,2-dichloroethane. The benchmark approach and human equivalent concentration (HEC) were adopted for 1,2-dichloroethane. The history of setting EQSs and guideline values for hazardous air pollutants is one of adopting new concepts into risk assessment.
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Affiliation(s)
- Toshihiro Kawamoto
- Department of Environmental Health, University of Occupational and Environmental Health, Japan.
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Tomenson JA. Update of a cohort mortality study of workers exposed to methylene chloride employed at a plant producing cellulose triacetate film base. Int Arch Occup Environ Health 2011; 84:889-97. [DOI: 10.1007/s00420-011-0621-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 01/30/2011] [Indexed: 11/28/2022]
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Samkange-Zeeb F, Schlehofer B, Schüz J, Schlaefer K, Berg-Beckhoff G, Wahrendorf J, Blettner M. Occupation and risk of glioma, meningioma and acoustic neuroma: results from a German case-control study (interphone study group, Germany). Cancer Epidemiol 2010; 34:55-61. [PMID: 20061201 DOI: 10.1016/j.canep.2009.12.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 12/08/2009] [Accepted: 12/09/2009] [Indexed: 12/11/2022]
Abstract
BACKGROUND Several epidemiological studies have investigated the association between occupation and brain tumour risk, but results have been inconclusive. We investigated the association between six occupational categories defined a priori: chemical, metal, agricultural, construction, electrical/electronic and transport, and the risk of glioma, meningioma and acoustic neuroma. METHODS In a population-based case-control study involving a total of 844 cases and 1688 controls conducted from 2000 to 2003, detailed information on life-long job histories was collected during personal interviews and used to create job calendars for each participant. Job title, job activity, job number, and the starting and ending dates of the activity were recorded for all activities with duration of at least 1 year. Reported occupational activities were coded according to the International Standard Classification of Occupations 1988 (ISCO 88). For the analyses we focused on six a priori defined occupational sectors, namely chemical, metal, agricultural, construction, electrical/electronic and transport. Multiple conditional logistic regression analysis was used to estimate odds ratios and their 95% confidence intervals. RESULTS Most of the observed odds ratios were close to 1.0 for ever having worked in the six occupational sectors and risk of glioma, meningioma and acoustic neuroma. Sub-group analyses according to duration of employment resulted in two elevated odds ratios with confidence intervals excluding unity. CONCLUSIONS We did not observe an increased risk of glioma or meningioma for occupations in the agricultural, construction, transport, chemical, electrical/electronic and metal sectors. The number of 'significant' odds ratios is consistent with an overall 'null-effect'.
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Affiliation(s)
- F Samkange-Zeeb
- Institute of Medical Biostatistics, Epidemiology and Informatics, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Obere Zahlbacher Strasse 69, 55131 Mainz, Germany
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Clewell HJ, Gentry PR, Kester JE, Andersen ME. Evaluation of Physiologically Based Pharmacokinetic Models in Risk Assessment: An Example with Perchloroethylene. Crit Rev Toxicol 2008; 35:413-33. [PMID: 16097137 DOI: 10.1080/10408440590931994] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
One of the more problematic aspects of the application of physiologically based pharmacokinetic (PBPK) models in risk assessment is the question of whether the model has been adequately validated to provide confidence in the dose metrics calculated with it. A number of PBPK models have been developed for perchloroethylene (PCE), differing primarily in the parameters estimated for metabolism. All of the models provide reasonably accurate simulations of selected kinetic data for PCE in mice and humans and could thus be considered to be "validated" to some extent. However, quantitative estimates of PCE cancer risk are critically dependent on the prediction of the rate of metabolism at low environmental exposures. Recent data on the urinary excretion of trichloroacetic acid (TCA), the major metabolite of PCE, for human subjects exposed to lower concentrations than those used in previous studies, make it possible to compare the high- to low-dose extrapolation capability of the various published human models. The model of Gearhart et al., which is the only model to include a description of TCA kinetics, provided the closest predictions of the urinary excretion observed in these low-concentration exposures. Other models overestimated metabolite excretion in this study by 5- to 15-fold. A systematic discrepancy between model predictions and experimental data for the time course of the urinary excretion of TCA suggested a contribution from TCA formed by metabolism of PCE in the kidney and excreted directly into the urine. A modification of the model of Gearhart et al. to include metabolism of PCE to TCA in the kidney at 10% of the capacity of the liver, with direct excretion of the TCA formed in the kidney into the urine, markedly improved agreement with the experimental time-course data, without altering predictions of liver metabolism. This case study with PCE demonstrates the danger of relying on parent chemical kinetic data to validate a model that will be used for the prediction of metabolism.
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19
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Bondy ML, Scheurer ME, Malmer B, Barnholtz-Sloan JS, Davis FG, Il'yasova D, Kruchko C, McCarthy BJ, Rajaraman P, Schwartzbaum JA, Sadetzki S, Schlehofer B, Tihan T, Wiemels JL, Wrensch M, Buffler PA. Brain tumor epidemiology: consensus from the Brain Tumor Epidemiology Consortium. Cancer 2008; 113:1953-68. [PMID: 18798534 PMCID: PMC2861559 DOI: 10.1002/cncr.23741] [Citation(s) in RCA: 582] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Epidemiologists in the Brain Tumor Epidemiology Consortium (BTEC) have prioritized areas for further research. Although many risk factors have been examined over the past several decades, there are few consistent findings, possibly because of small sample sizes in individual studies and differences between studies in patients, tumor types, and methods of classification. Individual studies generally have lacked samples of sufficient size to examine interactions. A major priority based on available evidence and technologies includes expanding research in genetics and molecular epidemiology of brain tumors. BTEC has taken an active role in promoting understudied groups, such as pediatric brain tumors; the etiology of rare glioma subtypes, such as oligodendroglioma; and meningioma, which, although it is not uncommon, has only recently been registered systematically in the United States. There also is a pressing need for more researchers, especially junior investigators, to study brain tumor epidemiology. However, relatively poor funding for brain tumor research has made it difficult to encourage careers in this area. In this report, BTEC epidemiologists reviewed the group's consensus on the current state of scientific findings, and they present a consensus on research priorities to identify which important areas the science should move to address.
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Affiliation(s)
- Melissa L Bondy
- Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
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20
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Boeniger M, Neumeister C, Booth-Jones A. Sampling and analytical method development and hand wipe measurements of dermal exposures to polycyclic aromatic hydrocarbons. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2008; 5:417-425. [PMID: 18464095 DOI: 10.1080/15459620802111319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This article describes the laboratory assessment of a hand and surface wipe sampling method for polycyclic aromatic hydrocarbons (PAHs). The analytical method employed extraction of the wipe samples into dimethyl sulfoxide (DMSO) and high-performance liquid chromatography (HPLC) flourometric detection of pyrene, a predominant PAH in used gasoline engine oils (UGEO). Recovery of pyrene was evaluated for two different sampling media by first contaminating the hands of a small number of volunteers with UGEO, followed by applying a small amount of corn oil to the palms, and by wiping the skin with a Whatman cellulostic filter paper or a polyester fabric wipe (i.e., Alpha wipes). In summary, using either Whatman or Alpha wipes, the mean recovery of pyrene from the UGEO that was applied to the hands and contained within three consecutive wipes was 69% and 54%, respectively. However, the relative recovery of the first to second wipe was on average 47% and 75% for the two media, respectively. These results indicate that the Alpha wipes were more efficient at recovering pyrene in the first wipe but less efficient overall when all three consecutive samples were included. Even though this sampling was performed in a controlled laboratory environment, the minimum and maximum amount of pyrene recovered in the individual composite samples using either method spanned a range of twofold. Overall, intra-and interpersonal variability, as measured by coefficient of variation, were 22% and 19%, respectively, and were not statistically different by type of media used. This method was used in a pilot field survey to sample the hands of 18 automotive repair technicians and 18 office workers. Detectable amounts of pyrene (>0.2 microg/sample) were found on the hands of 61% and 0% of these two groups, respectively, with the highest measured quantity equal to 1.06 microg. Samples from the upper surfaces of automobile motors were generally low to nondetectable (<0.027 microg/sample), while the median value of 0.047 mkcrlg/50 cm(2)(CV = 160%) and up to 0.640 microg were found on the drip pans.
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Affiliation(s)
- Mark Boeniger
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio, USA.
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21
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Chatti S, Debbabi F, Guesmi H, El Maalel O, Baccouche N, Krifa H, Mrizak N. Étude de l’exposition professionnelle chez les patients atteints de tumeurs cérébrales primitives malignes. ARCH MAL PROF ENVIRO 2007. [DOI: 10.1016/s1775-8785(07)78229-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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Nagano K, Sasaki T, Umeda Y, Nishizawa T, Ikawa N, Ohbayashi H, Arito H, Yamamoto S, Fukushima S. Inhalation carcinogenicity and chronic toxicity of carbon tetrachloride in rats and mice. Inhal Toxicol 2007; 19:1089-103. [PMID: 17957549 DOI: 10.1080/08958370701628770] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Carcinogenicity and chronic toxicity of carbon tetrachloride were examined by inhalation exposure of 50 F344 rats and 50 BDF1 mice of both sexes to carbon tetrachloride at 0 (clean air), 5, 25, or 125 ppm (v/v) for 6 h/day, 5 days/wk, for 104 wk. Incidences of hepatocellular adenomas and carcinomas in rats and mice of both sexes and of adrenal pheochromocytomas in mice of both sexes were significantly increased dose-dependently. Hepatocellular carcinomas and cirrhosis significantly occurred in the 125-ppm-exposed rats of both sexes, and 3 cases of hepatocellular carcinomas and increased incidences of hepatic altered cell foci were noted in the 25-ppm-exposed female rats. Hepatocellular carcinomas were induced in mice of both sexes at 25 and 125 ppm, and hepatocellular adenomas occurred in females at 5 ppm without any degenerative or necrotic change in hepatocytes. Hepatocellular carcinomas metastasized to the lung. The chronic hepatotoxicity was characterized by cirrhosis, fibrosis, and fatty change in rats, and ceroid deposition, bile-duct proliferation, and hydropic change in mice. Survival rates were decreased in the 125-ppm-exposed rats and mice of both sexes and in the 25-ppm-exposed female mice, in association with decreased body weights. The decreased survival rates were considered to be causally related to both various tumors including hepatocellular carcinomas and severe chronic progressive nephropathy in rats and to hepatocellular carcinomas in mice. This study provided clear evidence of carcinogenicity for carbon tetrachloride in rats and mice. A cytotoxic-proliferative and genotoxic mode of action for carbon tetrachloride-induced hepatocarcinogenesis was suggested.
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Affiliation(s)
- Kasuke Nagano
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, Hadano, Kanagawa, Japan
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23
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Stupp R, Reni M, Gatta G, Mazza E, Vecht C. Anaplastic astrocytoma in adults. Crit Rev Oncol Hematol 2007; 63:72-80. [PMID: 17478095 DOI: 10.1016/j.critrevonc.2007.03.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Accepted: 03/21/2007] [Indexed: 11/23/2022] Open
Abstract
Anaplastic astrocytoma is an uncommon disease in the adult population. Prognosis is influenced by age, symptom duration, mental status and Karnofsky performance status. A truly complete resection, which is a recognized independent prognostic factor, is not possible and recurrence in the surgical cavity is common. Based on randomized data available, chemotherapy has consistently failed to improve the outcome of patients with anaplastic astrocytoma, while a meta-analysis showed a small, but significant improvement in survival favouring the use of chemotherapy. Outside a clinical trial, postoperative radiotherapy (30 x 2 Gy) remains the standard adjuvant therapy for most patients. For elderly patients, the application of treatment is usually based on performance status and neurological function. In recurrent disease, chemotherapy with temozolomide has been proven to be active and well-tolerated in phase II trials, but no comparative phase III trials of other cytotoxic drugs have been conducted.
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Affiliation(s)
- Roger Stupp
- University Hospital (CHUV), Lausanne, Switzerland.
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24
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Abstract
Based on toxicology, metabolism, animal studies, and human studies, occupational exposure to chlorinated aliphatic solvents (methanes, ethanes, and ethenes) has been associated with numerous adverse health effects, including central nervous system, reproductive, liver, and kidney toxicity, and carcinogenicity. However, many of these solvents remain in active, large-volume use. This article reviews the recent occupational epidemiology literature on the most widely used solvents, methylene chloride, chloroform, trichloroethylene, and tetrachloroethylene, and discusses other chlorinated aliphatics. The impact of studies to date has been lessened because of small study size, inability to control for confounding factors, particularly smoking and mixed occupational exposures, and the lack of evidence for a solid pathway from occupational exposure to biological evidence of exposure, to precursors of health effects, and to health effects. International differences in exposure limits may provide a "natural experiment" in the coming years if countries that have lowered exposure limits subsequently experience decreased adverse health effects among exposed workers. Such decreases could provide some evidence that higher levels of adverse health effects were associated with higher levels of solvent exposure. The definitive studies, which should be prospective biomarker studies incorporating body burden of solvents as well as markers of effect, remain to be done.
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Affiliation(s)
- Avima M Ruder
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, OH 45226, USA.
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25
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Starr TB, Matanoski G, Anders MW, Andersen ME. Workshop Overview: Reassessment of the Cancer Risk of Dichloromethane in Humans. Toxicol Sci 2006; 91:20-8. [PMID: 16507920 DOI: 10.1093/toxsci/kfj145] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The U.S. Environmental Protection Agency (U.S. EPA) classifies dichloromethane (DCM) as a "probable human carcinogen," based upon its risk assessment conducted in the late 1980s (http://www.epa.gov/iris/subst/0070.htm). Since that time, cancer risk-assessment practices have evolved, leading to improved scientifically based methods for estimating risk and for illuminating as well as reducing residual uncertainties. A new physiologically based pharmacokinetic (PBPK) model has been developed, using data from human volunteers exposed to low DCM levels, that provides new information on the human to human variability in DCM metabolism and elimination (L. M. Sweeney et al., 2004, Toxicol. Lett. 154, 201-216). This information, along with data from other published human studies, has been used to develop a new cancer risk estimation model utilizing probabilistic methodology similar to that employed recently by U.S. EPA for other chemicals (ENVIRON Health Sciences Institute, 2005, Development of population cancer risk estimates for environmental exposure to dichloromethane using a physiologically based pharmacokinetic model. Final Report to Eastman Kodak Company). This article summarizes the deliberations of a scientific peer-review panel convened on 3 and 4 May 2005 at the CIIT Centers for Health Research in Research Triangle Park, North Carolina, to review the "state of the science" for DCM and to critically evaluate the new information for its utility in assessing potential human cancer risks from DCM exposure. The panel (Melvin E Andersen, CIIT Centers for Health Research, Research Triangle Park, NC 27709; A. John Bailer, Miami University, Scripps Gerontology Center, Oxford, OH 45056; Kenneth S. Crump, ENVIRON Health Sciences Institute, Ruston, LA 71270; Clifford R. Elcombe, University of Dundee, Biomedical Research Centre, Dundee DD1 9SY, United Kingdom; Linda S. Erdreich, Exponent, 420 Lexington Avenue, Suite 1740, New York, NY 10170; Jeffery W. Fisher, University of Georgia, Department of Environmental Health Science, Athens, GA 30602; David Gaylor, Gaylor and Associates, LLC, Eureka Springs, AR 72631; F Peter Guengerich, Vanderbilt University, Department of Biochemistry, Nashville, TN 37232; Kenneth Mundt, ENVIRON Health Sciences Institute, Amherst, MA 01004; Lorenz R Rhomberg, Gradient Corporation, Cambridge, MA 021138; Charles Timchalk, Pacific Northwest National Laboratory, Richland, WA 99352), chaired by M.E.A., was composed of experts in xenobiotic metabolism and carcinogenic mechanisms, PBPK modeling, epidemiology, biostatistics, and quantitative risk assessment. Observers included representatives from U.S. EPA, CIIT, and Eastman Kodak Company (Kodak), as well as several consultants to Kodak. The workshop was organized and sponsored by Kodak, which employs DCM as a solvent in the production of imaging materials. Overall, the panel concluded that the new models for DCM risk assessment were scientifically and technically sound and represented an advance over those employed in past assessments.
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26
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Loyant V, Jaffré A, Breton J, Baldi I, Vital A, Chapon F, Dutoit S, Lecluse Y, Loiseau H, Lebailly P, Gauduchon P. Screening of TP53 mutations by DHPLC and sequencing in brain tumours from patients with an occupational exposure to pesticides or organic solvents. Mutagenesis 2005; 20:365-73. [PMID: 16105905 DOI: 10.1093/mutage/gei052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The aetiology of brain tumours remains unclear. Occupational exposures to pesticides and organic solvents are suspected risk factors. The case-control study CEREPHY (221 cases, 442 controls) carried in the Departement de la Gironde in France revealed a significantly increased risk of brain tumours for subjects most exposed to pesticides. In some cancers, TP53 mutations could reflect exposure to specific carcinogens. These mutations are present in approximately 30% of astrocytic brain tumours. In a pilot study, we explored the hypothesis that pesticide or solvent exposure could raise the frequency of TP53 mutations in brain tumour cells. We investigated TP53 mutations in exons 2-11 by denaturing high performance liquid chromatography (DHPLC) and sequencing, and p53 accumulation by immunohistochemistry in brain tumour of the 30 patients from CEREPHY study with a history of occupational exposure to pesticides (n = 21) and/or organic solvents (n = 14) for whom tumoral tissue was available. Included cases concerned 27% of CEREPHY cases exposed to pesticides and, based on the cumulative index of occupational exposure, they were more exposed to pesticides. There were 12 gliomas, 6 meningiomas, 7 neurinomas, 2 central nervous system lymphomas and 3 tumours of other histological types. We detected TP53 mutations in three tumours, which is similar to the expected number (3.3) calculated from 46 published studies referenced in the IARC TP53 mutations database, taking into account histological types. Considering TP53 mutations previously detected in the laboratory by DHPLC and the frequency of TP53 polymorphisms detected in this sample (similar to published data), the TP53 mutations rate is probably not underestimated. These preliminary results, even if it was on a limited number of tumours, are not in favour of the role of pesticide or organic solvent exposure in the occurrence of TP53 mutations in brain tumours.
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Affiliation(s)
- V Loyant
- Groupe Régional d'Etudes sur le Cancer, Université de Caen Basse-Normandie, Centre François Baclesse, Avenue du Général Harris, BP5026, 14076 Caen Cedex 05, France.
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Beddowes EJ, Faux SP, Chipman JK. Chloroform, carbon tetrachloride and glutathione depletion induce secondary genotoxicity in liver cells via oxidative stress. Toxicology 2003; 187:101-15. [PMID: 12699900 DOI: 10.1016/s0300-483x(03)00058-1] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Chemical carcinogens are generally classified as genotoxic or non-genotoxic. However, weak genotoxicity at high concentrations is sometimes observed and interpretation is often problematic. In addition, certain rodent carcinogens exert their effects at doses associated with cytotoxicity and compensatory hyperplasia may be a contributing factor to tumourogenesis. We hypothesise that certain substances, at high concentrations, can induce an oxidative stress via the depletion of glutathione (GSH) and other antioxidant defences and that this may lead to indirect genotoxicity, that could contribute to carcinogenicity. In support of this, human HepG2 cells treated with buthionine sulphoximine (BSO) to deplete GSH, exhibited DNA strand breaks alongside elevated 8-oxodeoxyguanosine (8-oxodG) and malondialdehyde deoxyguanosine (M(1)dG) adducts under conditions associated with lipid peroxidation. Chloroform and carbon tetrachloride are rodent carcinogens with characteristics as described above. In female rat hepatocytes, chloroform treatment resulted in a small dose-dependent increase in M(1)dG adducts (4 mM and above), DNA strand breakage (8 mM and above) and lipid peroxidation, in the absence of any associated increase in DNA oxidation. GSH depletion only occurred in association with cytotoxicity (20 mM; lactate dehydrogenase release). Alongside lipid peroxidation, carbon tetrachloride (1 and 4 mM) produced a small elevation in M(1)dG adducts and DNA strand breaks and increases in 8-oxodG were observed at the threshold of, and concomitant with, cytotoxicity (4 mM). These effects may contribute to high dose genotoxicity and carcinogenicity. Non-linearity in the dose response is expected on the basis of depletion of antioxidants, and therefore, a pragmatic threshold for biologically relevant responses should exist.
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Affiliation(s)
- Emma J Beddowes
- School of Biosciences, University of Birmingham, Edgbaston, UK
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Navas-Acién A, Pollán M, Gustavsson P, Plato N. Occupation, exposure to chemicals and risk of gliomas and meningiomas in Sweden. Am J Ind Med 2002; 42:214-27. [PMID: 12210690 DOI: 10.1002/ajim.10107] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Occupational exposures may be related to the development of brain cancer. The objective was to estimate occupational-specific risk of gliomas and meningiomas among Swedish men and women gainfully employed in 1970 over the period 1971-1989, and the influence of occupational exposure to chemical substances. METHODS A dataset linking cancer diagnoses from the Swedish national cancer register to occupational and demographical data obtained in the 1970 census was used to fit log-linear Poisson models, in order to obtain relative risks adjusted by age, period, geographical area and town size. Exposure to 13 chemicals was assessed using a Swedish job-exposure matrix. RESULTS The main findings of this study among men were the increased risk of glioma with occupational exposure to arsenic, mercury, and petroleum products and of meningioma with lead. Women in occupational sectors with a higher socio-economic status showed an increased incidence of both, gliomas and meningiomas. CONCLUSIONS Occupational exposure to some chemicals appeared to be related with an increased risk of glioma and meningioma in men. Exposures involved in glioma and meningioma development seemed to be different.
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Affiliation(s)
- Ana Navas-Acién
- Cancer and Environmental Epidemiology Area, National Center for Epidemiology, Carlos III Institute of Health, Madrid, Spain
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29
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Wesseling C, Pukkala E, Neuvonen K, Kauppinen T, Boffetta P, Partanen T. Cancer of the brain and nervous system and occupational exposures in Finnish women. J Occup Environ Med 2002; 44:663-8. [PMID: 12134530 DOI: 10.1097/00043764-200207000-00013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Occupational agents were evaluated for the risk of brain-nervous system cancer in a cohort of 413,877 Finnish women with blue-collar occupations in 1970. Observed and expected numbers of incident cases and the intensities of exposure to 25 agents were generated for 183 job titles from 1971 to 1995. Poisson regression models linked incidence and exposure data. Increased risks were found for medium/high intensities of iron (standardized incidence ratio [SIR], 2.15; 95% confidence interval [CI], 0.96 to 4.80), oil mist (1.95; 0.97 to 3.90), any chromium compounds (1.51; 0.85 to 2.67), electromagnetic fields (1.37; 0.98 to 2.10), aliphatic and alicyclic hydrocarbon compounds (1.34; 0.80 to 2.27), lead (1.27; 0.81 to 2.01), cadmium (1.26; 0.72 to 2.22), and aromatic hydrocarbon compounds (1.20; 0.71 to 2.03). Strengths of the study include fair number of cases, virtually complete case coverage, and a high-quality job exposure matrix. Ecological design and cross-sectional job assessment introduced exposure misclassification and tended to drive risk estimates toward unity.
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Affiliation(s)
- Catharina Wesseling
- Department of Epidemiology and Biostatistics, Finnish Institute of Occupational Health, Helsinki, Finland
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30
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Sherratt PJ, Williams S, Foster J, Kernohan N, Green T, Hayes JD. Direct comparison of the nature of mouse and human GST T1-1 and the implications on dichloromethane carcinogenicity. Toxicol Appl Pharmacol 2002; 179:89-97. [PMID: 11884241 DOI: 10.1006/taap.2002.9348] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dichloromethane (DCM) is a hepatic and pulmonary carcinogen in mice exposed to high doses by inhalation. It has been shown previously that the incidence of liver and lung tumors does not increase in rats or hamsters exposed to the dihaloalkane under conditions similar to those that produced tumors in mice. The biological consequences of DCM exposure to humans is therefore uncertain. The carcinogenic effects of DCM in the mouse are caused by the interaction with DNA of a glutathione (GSH) conjugate that is produced by the class theta glutathione S-transferase T1-1 (GST T1-1). The species specificity is thought to be due to the greater amount of transferase activity in mouse target organs and specific nuclear localization of GST T1-1 in target cells. This paper directly compares the relative capacity and locality of DCM activation in mouse and human tissues. The results show that mouse GST T1-1 is more efficient in catalyzing the conjugation of DCM with GSH than the orthologous human enzyme. In addition, the mouse expresses higher levels of the transferase than humans in hepatic tissue. Histochemical analysis confirmed the presence of GST T1-1 in the nucleus of mouse liver cells. However, in human liver GST T1-1 was detected in bile duct epithelial cells and hepatocyte nuclei but was also present in the cytoplasm. Taking this information into account, it is unlikely that humans have a sufficiently high capacity to activate DCM for this compound to be considered to represent a carcinogenic risk.
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Affiliation(s)
- Philip J Sherratt
- Biomedical Research Centre, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland, DD1 9SY, United Kingdom
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Rudén C. The use and evaluation of primary data in 29 trichloroethylene carcinogen risk assessments. Regul Toxicol Pharmacol 2001; 34:3-16. [PMID: 11502152 DOI: 10.1006/rtph.2001.1482] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This paper reports the results from a detailed study on how risk assessments of chemicals are actually made. The study is performed by comparing 29 cancer risk assessments made of one and the same chemical substance, namely, trichloroethylene. In this paper, the conclusions that are drawn in these risk assessment documents are described, and differences between the conclusions are explored. This is made within the framework of a proposed cancer risk assessment index. The selection of scientific data for risk assessment purposes is analyzed and the different risk assessors' interpretations and evaluations of individual primary data are compared. It is concluded that the data sets utilized by the trichloroethylene risk assessors are surprisingly incomplete and that biased data selection may have influenced some of the risk assessors' conclusions. Different risk assessors often interpret and evaluate one and the same study in different ways. There are also indications of both interpretation bias and evaluation bias for some of the risk assessors.
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Affiliation(s)
- C Rudén
- Philosophy Unit, Royal Institute of Technology, S-100 44 Stockholm, Sweden
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32
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Zheng T, Cantor KP, Zhang Y, Keim S, Lynch CF. Occupational risk factors for brain cancer: a population-based case-control study in Iowa. J Occup Environ Med 2001; 43:317-24. [PMID: 11322092 DOI: 10.1097/00043764-200104000-00005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A number of occupations and industries have been inconsistently associated with the risk of brain cancer. To further explore possible relationships, we conducted a population-based case-control study of brain glioma in the state of Iowa, involving 375 histologically confirmed incident cases and 2434 population-based controls. Among men, the industries and/or occupations that had a significantly increased risk for employment of more than 10 years included roofing, siding, and sheet metalworking; newspaper work; rubber and plastics products, particularly tires and inner tubes; miscellaneous manufacturing industries; wholesale trade of durable goods, grain, and field beans; cleaning and building service occupations; miscellaneous mechanics and repairers; and janitors and cleaners. Subjects who worked in plumbing, heating, and air conditioning; electrical services; gasoline service stations; and military occupations also experienced a significantly increased risk. Among women, significant excess risk was observed for occupations in agricultural services and farming, apparel and textile products, electrical and electronic equipment manufacturing, various retail sales, record-keeping, and restaurant service. Workers in industries with a potential for gasoline or motor exhaust exposures experienced a non-significant excess risk of brain glioma.
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Affiliation(s)
- T Zheng
- Yale University School of Public Health, New Haven, USA.
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Medrado-Faria MD, de Almeida JW, Zanetta DM, Gattás GJ. Nervous system cancer mortality in an industrialized area of Brazil 1980-1993. ARQUIVOS DE NEURO-PSIQUIATRIA 2000; 58:412-7. [PMID: 10920400 DOI: 10.1590/s0004-282x2000000300003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES The industrialization process and nervous system cancer (NSC) mortality in a urban region of Brazil. METHOD From registries of the State System of Data Analysis Foundation (SEADE), 103 males deaths by NSC (ICD-9) in Baixada Santista (BS), from 1980 to 1993 were selected. Mortality ratios were calculated comparing the standardized mortality rate for ages over 10 years old (G1) and for the age group from 35 to 64 years old, in the industrialized and non-industrialized areas in three periods: 1980-1993, 1980-86, 1987-93. RESULTS A statiscally significant high mortality was observed in the industrialized area, for ages over 10 in all periods and only from 1980 to 1993 for ages from 34 to 64. The highest mortality ratio occurred from 1980-86 for ages over 10 - 4.12 (CI 1.79-9.42). CONCLUSION High mortality was probably related to the environmental and occupational exposure to many organic and inorganic chemical substances, considered carcinogenics, such as aliphatic and aromatic hydrocarbons, organochlorinated, formaldehyde, nitrogenated compounds and heavy metals, found in the port and industrial complex. We discuss the importance of case-control studies in characterizing the association of these and other risk factors in the determination of NSC.
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Affiliation(s)
- M D Medrado-Faria
- Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, Brazil
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Wartenberg D, Reyner D, Scott CS. Trichloroethylene and cancer: epidemiologic evidence. ENVIRONMENTAL HEALTH PERSPECTIVES 2000; 108 Suppl 2:161-76. [PMID: 10807550 PMCID: PMC1637753 DOI: 10.1289/ehp.00108s2161] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Trichloroethylene is an organic chemical that has been used in dry cleaning, for metal degreasing, and as a solvent for oils and resins. It has been shown to cause liver and kidney cancer in experimental animals. This article reviews over 80 published papers and letters on the cancer epidemiology of people exposed to trichloroethylene. Evidence of excess cancer incidence among occupational cohorts with the most rigorous exposure assessment is found for kidney cancer (relative risk [RR] = 1.7, 95% confidence interval [CI] 1.1-2.7), liver cancer (RR = 1.9, 95% CI(1.0-3.4), and non-Hodgkin's lymphoma (RR = 1.5, 95% CI 0.9-2.3) as well as for cervical cancer, Hodgkin's disease, and multiple myeloma. However, since few studies isolate trichloroethylene exposure, results are likely confounded by exposure to other solvents and other risk factors. Although we believe that solvent exposure causes cancer in humans and that trichloroethylene likely is one of the active agents, we recommend further study to better specify the specific agents that confer this risk and to estimate the magnitude of that risk.
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Affiliation(s)
- D Wartenberg
- Environmental and Occupational Health Sciences Institute, UMDNJ--Robert Wood Johnson Medical School, Piscataway, NJ 08855, USA.
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Abstract
Millions of workers in the United States are recurrently exposed to solvents throughout their working lives. Members of this class of compounds share the ability to dissolve waxes, fats, and oils as their common characteristic. This review offers the health practitioner a practical approach to the diagnosis, management, and prevention of solvent-related disorders that result from exposures to these compounds in the workplace. A description of commonly used solvents is provided, along with a brief review of the literature that documents their acute and chronic effects on health.
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Affiliation(s)
- J Q Xiao
- Eastern New York Occupational and Environmental Health Center, 155 Washington Avenue, New York 12210, USA.
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Hearne FT, Pifer JW. Mortality study of two overlapping cohorts of photographic film base manufacturing employees exposed to methylene chloride. J Occup Environ Med 1999; 41:1154-69. [PMID: 10609238 DOI: 10.1097/00043764-199912000-00022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The mortality experience of two overlapping cohorts of employees engaged in the manufacture of photographic film support was evaluated to assess the potential chronic health effects of methylene chloride exposure. In the first analysis, we examined causes of death among 1311 men initially employed between 1946 (when the solvent was first used) and 1970; in the second, we updated mortality in a 1964 to 1970 employed cohort of 1013 men. Follow-up was through 1994. The mean exposure among members of the 1946 to 1970 cohort was 39 ppm (8-hour time-weighted average) for 17 years, and the median length of follow-up from first exposure was 34 years. Members of the 1964 to 1970 cohort received an average exposure of 26 ppm for 24 years; median time from first exposure was 35 years. Compared with general population vital statistics, mortality in both cohorts was below expectation for all causes of death, ischemic heart disease, and cancer, including such sites as the lung and liver, which were target organs identified in animal toxicology studies. No statistically significant increases were observed for any cause of death. The combined results of this study and three others in the photographic film and textile fibers industries (approximately 7300 subjects) show that long-term exposure to methylene chloride does not increase the risk of death from any cause including specific diagnoses that have been associated with this widely used solvent.
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Affiliation(s)
- F T Hearne
- Epidemiology Section, Corporate Health, Safety, and Environment, Eastman Kodak Company, Rochester, N.Y., USA
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Donoghue AM. Inhalation of ammonium nitrate fuel oil explosive; and possible concomitant exposure. Occup Environ Med 1999; 56:215. [PMID: 10448333 PMCID: PMC1757715 DOI: 10.1136/oem.56.3.215b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
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Lynge E. Mortality of workers exposed to methylene chloride employed at a plant producing cellulose triacetate film base. Occup Environ Med 1999; 56:215. [PMID: 10448332 PMCID: PMC1757708 DOI: 10.1136/oem.56.3.215a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Brennan RJ, Schiestl RH. Chloroform and carbon tetrachloride induce intrachromosomal recombination and oxidative free radicals in Saccharomyces cerevisiae. Mutat Res 1998; 397:271-8. [PMID: 9541652 DOI: 10.1016/s0027-5107(97)00225-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chlorination of drinking water results in the generation of low levels of numerous chlorinated hydrocarbons due to the reaction of chlorine with naturally occurring organic compounds in the water. Concern has been raised about the safety of these chlorinated contaminants as several of them, most notably chloroform (trichloromethane), have been shown to be carcinogenic in long-term rodent bioassays and weak correlations between trihalomethane levels in drinking water and an increased risk of bladder and colorectal cancer in humans have been found. Chloroform and carbon tetrachloride induce liver cancer in rats and mice only at doses where significant hepatotoxicity is observed and have been classed as non-genotoxic carcinogens. We have investigated the ability of chloroform, carbon tetrachloride and 1,1,1-trichloroethane to induce deletions via intrachromosomal recombination in the yeast Saccharomyces cerevisiae. Chloroform and carbon tetrachloride induced this genotoxic recombination event at similar doses, 1,1,1-Trichloroethane gave only a weak response in the DEL recombination assay and only at the highest dose. We further show that chloroform and carbon tetrachloride, but not trichloroethane, induced oxidative free radical species in our yeast strain. The free radical scavenger N-acetylcysteine reduced chloroform-induced toxicity and recombination, and both chloroform and carbon tetrachloride were able to oxidize the free radical-sensitive reporter compound dichlorofluorescein diacetate in vivo. The implications of these findings to the carcinogenic activities of the three compounds are discussed.
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Affiliation(s)
- R J Brennan
- Department of Molecular and Cellular Toxicology, Harvard School of Public Health, Boston, MA 02115-6012, USA
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Witten J, Sagunski H, Wildeboer B. Richtwerte für die Innenraumluft: Dichlormethan. ACTA ACUST UNITED AC 1997. [DOI: 10.1007/bf03044087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Tomenson JA, Bonner SM, Heijne CG, Farrar DG, Cummings TF. Mortality of workers exposed to methylene chloride employed at a plant producing cellulose triacetate film base. Occup Environ Med 1997; 54:470-6. [PMID: 9282122 PMCID: PMC1128815 DOI: 10.1136/oem.54.7.470] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To study mortality among 1785 employees of a factory that produced cellulose triacetate film base at Brantham in the United Kingdom. Also, to investigate patterns of mortality after exposure to methylene chloride; in particular, mortality from liver and biliary tract cancer, lung cancer, pancreatic cancer, and cardiovascular disease. SUBJECTS AND METHODS All male employees with a record of employment at the film factory in 1946-88. A total of 1473 subjects worked in jobs that entailed exposure to methylene chloride. The mean duration of exposure was nine years at 19 ppm (eight hour time weighted average). RESULTS In the cohort, 334 deaths were identified up to 31 December 1994. Mortalities for the cohort were compared with national and local rates and expressed as standardised mortality ratios (SMR). In the subcohort of workers exposed to methylene chloride, substantially reduced mortalities compared with national and local rates were found for all causes, all cancers, and the principal cancer sites of interest. The significantly reduced lung cancer mortalities in exposed workers (SMR 48) seemed to reflect the restrictions on smoking at the workplace. In contrast, mortality from ischaemic heart disease in exposed workers, although lower than national rates (SMR 92), was slightly increased compared with local rates. However, mortality from ischaemic heart disease was lower in active employees (SMR 83) where a direct effect of exposure to methylene chloride should be concentrated. No in service mortality due to ischaemic heart disease was found in workers with the highest cumulative exposure (> or = 800 ppm-years). CONCLUSIONS The study provided no indication that employment at the plant, or exposure to methylene chloride, had adversely affected the mortalities of workers.
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Affiliation(s)
- J A Tomenson
- ICI Epidemiology Unit, Winnington, Northwich, Cheshire
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Green T. Methylene chloride induced mouse liver and lung tumours: an overview of the role of mechanistic studies in human safety assessment. Hum Exp Toxicol 1997; 16:3-13. [PMID: 9023569 DOI: 10.1177/0960327197016001021] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
B6C3F1 mice exposed to high dose levels of methylene chloride by inhalation for 2 years had an elevated incidence of liver and lung tumours. These tumours were not increased in rats or hamsters exposed under the same or similar conditions. This paper gives an overview of research conducted over the last 10 years into the mechanism of action of methylene chloride as a mouse carcinogen and into the relevance of the mouse data to humans exposed to this chemical. Data are presented on the comparative metabolism and pharmacokinetics of methylene chloride in mice, rats, hamsters and humans, on the toxicity of methylene chloride to the target organs in the mouse, and on the genotoxicity of methylene chloride in vitro and in vivo. The enzyme which activates methylene chloride to its carcinogenic form has been isolated, sequenced, and cloned, and its distribution studied within cells, organs and between species. Evidence has been obtained to show the methylene chloride caused cancer in mice as a result of interactions between metabolites of the glutathione S-transferase pathway and DNA. Damage to mouse lung Clara cells and increased cell division are believed to have influenced the development of the lung tumours. The species specificity was a direct consequence of the very high activity and specific cellular and nuclear localisation of a theta class glutathione S-transferase enzyme which was unique to the mouse. Consequently, DNA damage was not detectable in rats in vivo, or in hamster and human hepatocytes exposed to cytotoxic dose levels of methylene chloride in vitro. These results provide evidence that the mouse is unique in its response to methylene chloride and that it is an inappropriate model for human health assessment.
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Affiliation(s)
- T Green
- Zeneca Central Toxicology Laboratory, Macclesfield, Cheshire, UK
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Rodvall Y, Ahlbom A, Spännare B, Nise G. Glioma and occupational exposure in Sweden, a case-control study. Occup Environ Med 1996; 53:526-32. [PMID: 8983463 PMCID: PMC1128535 DOI: 10.1136/oem.53.8.526] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The aim of the study was to analyse whether any job titles, industrial codes, and certain occupational exposures were associated with an increased risk of glioma. METHODS A population based case-control study of incident primary brain tumours in adults was carried out in Uppsala, Sweden in the period 1987-90. The study included 192 cases of glioma and 192 matched controls. It also included cases with other tumours of the central nervous system with matched controls. Information from all 343 controls was used in this study. Information was collected by means of a questionnaire that was sent to all subjects. An occupational hygienist reviewed the questionnaires for self reported exposures to substances and assessed whether these reported exposures were plausible or not in the corresponding occupation. RESULTS The kappa coefficient for those classified by the two methods ranged between 0.46 and 0.88, and they were almost the same for cases and controls. For men exposed to solvents a relative risk (RR) of 2.6 (95% CI 1.3 to 5.2) was found. For men exposed to pesticides the RR was 1.8 (95% CI 0.6 to 5.1), and for plastic materials the RR was 3.6 (95% CI 1.0 to 12.4). For men employed in forestry and logging the RR was 2.2 (95% CI 0.9 to 5.3) and in basic metal industries 2.0 (95% CI 1.0 to 4.0). CONCLUSION An increased risk of glioma was associated with use of solvents, pesticides, and plastic materials but this should be interpreted with some caution.
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Affiliation(s)
- Y Rodvall
- Institute of Environmental Medicine, Stockholm, Sweden
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Affiliation(s)
- N S Weiss
- University of Washington, Seattle 98195, USA
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Berleur MP, Cordier S. The role of chemical, physical, or viral exposures and health factors in neurocarcinogenesis: implications for epidemiologic studies of brain tumors. Cancer Causes Control 1995; 6:240-56. [PMID: 7612804 DOI: 10.1007/bf00051796] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This review highlights some future prospects and implications for epidemiologic research on the etiology of nervous system tumors. It reviews some points regarding physiology of the nervous system, in connection with mechanisms of neurocarcinogenesis, and experimental studies in animals. The results of epidemiologic studies are summarized in the light of the biological and experimental observations. The following aspects are particularly emphasized: (i) higher susceptibility of the developing nervous system to neurocarcinogenic agents (in the fetus and after birth); (ii) possible implications of knowledge about mechanisms of neurocarcinogenesis regarding crossing of the blood-brain barrier, activation of oncogenes and inactivation of anti-oncogenes, relationship between chemical structure and neurocarcinogenic action; (iii) necessity of further investigation concerning the occurrence of nitrosoureas and their precursors in the environment, and the potential role of nitroso compounds in the development of human brain tumors; (iv) lack of information about promoting or inhibiting neurocarcinogenic effects, and co-carcinogenesis--among others, interaction between X-irradiation and exposure to neurocarcinogenic nitrosoureas; (v) need for studying the potential neurocarcinogenic risk of polyomaviruses BKV, JCV, and SV40 to humans.
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Affiliation(s)
- M P Berleur
- Institut National de la Santé et Recherche Médicale, Villejuif, France
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