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Li Y, Wang J, Yang Z, Li G, Zhang Z, Zhang D, Sun H. Oxidative stress and DNA damage in earthworms induced by methyl tertiary-butyl ether in natural soils. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:20514-20526. [PMID: 36258110 DOI: 10.1007/s11356-022-23679-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Adverse effects of methyl tertiary-butyl ether (MTBE) have been noticed at different trophic levels by international researchers. However, there was unclear evidence about its effects on oxidative stress and DNA damage in earthworms. In this study, earthworms were cultivated in various doses of MTBE (0.0 mg/kg, 10.0 mg/kg, 30.0 mg/kg, and 60.0 mg/kg) contaminated agricultural soil for 7 days, 14 days, 21 days, and 28 days, respectively. The result showed that the reactive oxygen species (ROS) content of earthworms significantly increased in MTBE treatment groups compared to the control group. In MTBE treatment groups, the activities of superoxide dismutase, catalase, peroxidase, and glutathione S-transferase were significantly activated at the exposure of 7 days, which increased by 36.3-78.9%, 51.8-97.3%, 36.5-61.9%, and 12.0-54.8%, respectively. Then, the activities of these defense enzymes showed various changes following the changes in exposure times and MTBE concentrations. Especially in the 60.0 mg kg-1 group, both antioxidant enzymes and GST were still significantly activated at the exposure of 14 days and then significantly inhibited at the exposure of 28 days. The analysis of olive tail moment showed significant DNA damage in the 10.0 mg kg-1 group at the exposure of 28 days, and this damage in 30.0 mg/kg and 60.0 mg/kg groups was found at the exposure of 7 days. This result was consistent with the malondialdehyde accumulation in earthworms. Additionally, the analysis of IBRv2 showed the effects of MTBE treatments on earthworms in dose- and time-dependent manners. This study helps better to understand the effects of MTBE on soil invertebrate animals and provide theoretical support for soil protection in governing MTBE application.
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Affiliation(s)
- Yanqiang Li
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Tai'an, 271000, China.
| | - Jun Wang
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Tai'an, 271000, China
| | - Zhongkang Yang
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Tai'an, 271000, China
| | - Guangde Li
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Tai'an, 271000, China
| | - Zhongwen Zhang
- Weifang Environmental Science Research & Design Institute, Weifang City, 26104, Shandong Province, China
| | - Dexin Zhang
- Bureau of Agriculture and Rural Affairs of Changle, Changle City, 262400, Shandong Province, China
| | - Hui Sun
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Tai'an, 271000, China
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Khassin AA, Minyukova TP. Contemporary Trends in Methanol Processing. CATALYSIS IN INDUSTRY 2022. [DOI: 10.1134/s2070050422010044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Sarhan OM, Jain A, Mutwally HMA, Osman GH, Yun Jung S, Issa T, Elmogy M. Impact Effect of Methyl Tertiary-Butyl Ether "Twelve Months Vapor Inhalation Study in Rats". BIOLOGY 2019; 9:biology9010002. [PMID: 31861902 PMCID: PMC7168921 DOI: 10.3390/biology9010002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/05/2019] [Accepted: 12/13/2019] [Indexed: 12/26/2022]
Abstract
We investigated the early risk of developing cancer by inhalation of low doses (60 µL/day) of methyl tertiary butyl ether (MTBE) vapors using protein SDS-PAGE and LC-MS/MS analysis of rat sera. Furthermore, histological alterations were assessed in the trachea and lungs of 60 adult male Wistar rats. SDS-PAGE of blood sera showed three protein bands corresponding to 29, 28, and 21 kDa. Mass spectroscopy was used to identify these three bands. The upper and middle protein bands showed homology to carbonic anhydrase 2 (CA II), whereas the lower protein band showed homology with peroxiredoxin 2. We found that exposure to MTBE resulted in histopathological alterations in the trachea and the lungs. The histological anomalies of trachea and lung showed that the lumen of trachea, bronchi, and air alveoli packed with free and necrotic epithelial cells (epithelialization). The tracheal lamina propria of lung demonstrated aggregation of lymphoid cells, lymphoid hyperplasia, hemorrhage, adenomas, fibroid degeneration, steatosis, foam cells, severe inflammatory cells with monocytic infiltration, edema, hemorrhage. Occluded, congested, and hypertrophied lung arteries in addition, degenerated thyroid follicles, were observed. The hyaline cartilage displayed degeneration, deformation, and abnormal protrusion. In conclusion, our results suggest that inhalation of very low concentrations of the gasoline additive MTBE could induce an increase in protein levels and resulted in histopathological alterations of the trachea and the lungs.
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Affiliation(s)
- Osama M. Sarhan
- Biology Department, Faculty of Science, Umm Al-Qura University, Makkah 673, Saudi Arabia; (O.M.S.); (H.M.A.M.)
- Zoology Department, Faculty of Science Fayoum University, Fayoum 63514, Egypt
| | - Antrix Jain
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Hamed M. A. Mutwally
- Biology Department, Faculty of Science, Umm Al-Qura University, Makkah 673, Saudi Arabia; (O.M.S.); (H.M.A.M.)
| | - Gamal H. Osman
- Biology Department, Faculty of Science, Umm Al-Qura University, Makkah 673, Saudi Arabia; (O.M.S.); (H.M.A.M.)
- Microbial Genetics Department, Agricultural Genetic Engineering Research Institute (AGERI), Giza, Cairo 12619, Egypt
- Research Laboratories Center, Faculty of Applied Science, Umm Al-Qura University, Mecca 24381, Saudi Arabia
- Correspondence:
| | - Sung Yun Jung
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Tawfik Issa
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Mohamed Elmogy
- Entomology Department, Cairo University, Giza 12613, Egypt;
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Tang Y, Ren Q, Wen Q, Yu C, Xie X, Hu Q, Du Y. Effect of methyl tert-butyl ether on adipogenesis and glucose metabolism in vitro and in vivo. J Environ Sci (China) 2019; 85:208-219. [PMID: 31471028 DOI: 10.1016/j.jes.2019.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/25/2019] [Accepted: 06/25/2019] [Indexed: 06/10/2023]
Abstract
Methyl tert-butyl ether (MTBE), as a widely used gasoline additive, is suspected of being environmentally toxic. MTBE accumulates mainly in adipose tissue, but its effect on obesity or obesity-related metabolic disorders has not been well understood yet. Therefore, we examined the effect of MTBE on the adipose function and the related metabolic processes with both 3T3-L1 cell line and C57BL/6J mice model. We found that exposure to MTBE at the environmental relevant concentration (100 μmol/L) could significantly induce differentiation of preadipocyte and disturb insulin-stimulated glucose uptake of mature adipocyte. The in vivo observation in male mice showed a positive correlation of visceral white adipose tissue (vWAT) expansion and cell size increase with MTBE treatment in 14 weeks. Glucose tolerance and insulin sensitivity tests demonstrated that MTBE at 1000 μg/(kg·day) disturbed the systemic glucose metabolism in a gender-specific manner, which might be partly attributed to the alterations of gut microbiota community at genus level with respect to Akkermansia, Clostridium XlVb, and Megamonas. In summary, our study characterized the effect of MTBE on adipose tissue function and glucose homeostasis in vitro and in vivo, and revealed that systemic disorders of the glucose metabolism might be modulated by the related gut microbiota.
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Affiliation(s)
- Yue Tang
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: .; School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qidong Ren
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: .; School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing Wen
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: .; School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Caixia Yu
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: .; School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinni Xie
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: ..
| | - Qing Hu
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yuguo Du
- State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. E-mail: .; School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
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Facetti JF, Nunez R, Gomez L C, Ojeda J, Bernal C, Leon-Ovelar R, Carvallo F. Methyl tert-butyl ether (MtBE) in deep wells of the Patiño Aquifer, Paraguay: A preliminary characterization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:1640-1650. [PMID: 30282328 DOI: 10.1016/j.scitotenv.2018.08.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/31/2018] [Accepted: 08/04/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Juan Francisco Facetti
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay.
| | - Roberto Nunez
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay
| | | | - Jose Ojeda
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay
| | - Cynthia Bernal
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay
| | - Regina Leon-Ovelar
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay
| | - Felix Carvallo
- Universidad Nacional de Asuncion, FIUNA, Department of Geography and Environment, Campus Universitario de San Lorenzo, Paraguay
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Beć KB, Grabska J, Huck CW, Ozaki Y, Hawranek JP. Computational and quantum chemical study on high-frequency dielectric function of tert-butylmethyl ether in mid-infrared and near-infrared regions. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.10.095] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Alfonso-Gordillo G, Cristiani-Urbina E, Flores-Ortiz CM, Peralta H, Cancino-Díaz JC, Cruz-Maya JA, Jan-Roblero J. Stenotrophomonas maltophilia isolated from gasoline-contaminated soil is capable of degrading methyl tert-butyl ether. ELECTRON J BIOTECHN 2016. [DOI: 10.1016/j.ejbt.2016.06.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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8
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Bogen KT, Heilman JM. Reassessment of MTBE cancer potency considering modes of action for MTBE and its metabolites. Crit Rev Toxicol 2016; 45 Suppl 1:1-56. [PMID: 26414780 DOI: 10.3109/10408444.2015.1052367] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A 1999 California state agency cancer potency (CP) evaluation of methyl tert-butyl ether (MTBE) assumed linear risk extrapolations from tumor data were plausible because of limited evidence that MTBE or its metabolites could damage DNA, and based such extrapolations on data from rat gavage and rat and mouse inhalation studies indicating elevated tumor rates in male rat kidney, male rat Leydig interstitial cells, and female rat leukemia/lymphomas. More recent data bearing on MTBE cancer potency include a rodent cancer bioassay of MTBE in drinking water; several new studies of MTBE genotoxicity; several similar evaluations of MTBE metabolites, formaldehyde, and tert-butyl alcohol or TBA; and updated evaluations of carcinogenic mode(s) of action (MOAs) of MTBE and MTBE metabolite's. The lymphoma/leukemia data used in the California assessment were recently declared unreliable by the U.S. Environmental Protection Agency (EPA). Updated characterizations of MTBE CP, and its uncertainty, are currently needed to address a variety of decision goals concerning historical and current MTBE contamination. To this end, an extensive review of data sets bearing on MTBE and metabolite genotoxicity, cytotoxicity, and tumorigenicity was applied to reassess MTBE CP and related uncertainty in view of MOA considerations. Adopting the traditional approach that cytotoxicity-driven cancer MOAs are inoperative at very low, non-cytotoxic dose levels, it was determined that MTBE most likely does not increase cancer risk unless chronic exposures induce target-tissue toxicity, including in sensitive individuals. However, the corresponding expected (or plausible upper bound) CP for MTBE conditional on a hypothetical linear (e.g., genotoxic) MOA was estimated to be ∼2 × 10(-5) (or 0.003) per mg MTBE per kg body weight per day for adults exposed chronically over a lifetime. Based on this conservative estimate of CP, if MTBE is carcinogenic to humans, it is among the weakest 10% of chemical carcinogens evaluated by EPA.
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Szabó Z, Gyula P, Robotka H, Bató E, Gálik B, Pach P, Pekker P, Papp I, Bihari Z. Draft genome sequence of Methylibium sp. strain T29, a novel fuel oxygenate-degrading bacterial isolate from Hungary. Stand Genomic Sci 2015. [PMID: 26221420 PMCID: PMC4517660 DOI: 10.1186/s40793-015-0023-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Methylibium sp. strain T29 was isolated from a gasoline-contaminated aquifer and proved to have excellent capabilities in degrading some common fuel oxygenates like methyl tert-butyl ether, tert-amyl methyl ether and tert-butyl alcohol along with other organic compounds. Here, we report the draft genome sequence of M. sp. strain T29 together with the description of the genome properties and its annotation. The draft genome consists of 608 contigs with a total size of 4,449,424 bp and an average coverage of 150×. The genome exhibits an average G + C content of 68.7 %, and contains 4754 protein coding and 52 RNA genes, including 48 tRNA genes. 71 % of the protein coding genes could be assigned to COG (Clusters of Orthologous Groups) categories. A formerly unknown circular plasmid designated as pT29A was isolated and sequenced separately and found to be 86,856 bp long.
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Affiliation(s)
- Zsolt Szabó
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Péter Gyula
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Hermina Robotka
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Emese Bató
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Bence Gálik
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Péter Pach
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Péter Pekker
- Materials Science Research Group, Hungarian Academy of Sciences-University of Miskolc, Miskolc, Hungary
| | - Ildikó Papp
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
| | - Zoltán Bihari
- Bay Zoltán Nonprofit Ltd. for Applied Research, Budapest, Hungary
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Ghasemi S, Ahmadi F. The study of binding of methyl tert-butyl ether to human telomeric G-quadruplex and calf thymus DNA by gas chromatography, a thermodynamic discussion. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 971:112-9. [DOI: 10.1016/j.jchromb.2014.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 08/30/2014] [Accepted: 09/09/2014] [Indexed: 12/27/2022]
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11
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García G, Trenzado JL, Alcalde R, Rodríguez-Delgado A, Atilhan M, Aparicio S. Structure of Alkylcarbonate + n-Alkane Mixed Fluids. J Phys Chem B 2014; 118:11310-22. [DOI: 10.1021/jp506791m] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gregorio García
- Department
of Chemistry, University of Burgos, 09001 Burgos, Spain
| | - José L. Trenzado
- Departamento
de Física, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas, G.C., Spain
| | - Rafael Alcalde
- Department
of Chemistry, University of Burgos, 09001 Burgos, Spain
| | - Ana Rodríguez-Delgado
- Departamento
de Física, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas, G.C., Spain
| | - Mert Atilhan
- Department
of Chemical Engineering, Qatar University, Doha 2713, Qatar
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Seddigi ZS, Bumajdad A, Ansari SP, Ahmed SA, Danish EY, Yarkandi NH, Ahmed S. Preparation and characterization of Pd doped ceria-ZnO nanocomposite catalyst for methyl tert-butyl ether (MTBE) photodegradation. JOURNAL OF HAZARDOUS MATERIALS 2014; 264:71-8. [PMID: 24275473 DOI: 10.1016/j.jhazmat.2013.10.070] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 10/27/2013] [Accepted: 10/29/2013] [Indexed: 05/08/2023]
Abstract
A series of binary oxide catalysts (ceria-ZnO) were prepared and doped with different amounts of palladium in the range of 0.5%-1.5%. The prepared catalysts were characterized by SEM, TEM, XRD and XPS, as well as by N2 sorptiometry study. The XPS results confirmed the structure of the Pd CeO2-x-ZnO. The photocatalytic activity of these catalysts was evaluated for degradation of MTBE in water. These photocatalyst efficiently degrade a 100ppm aqueous solution of MTBE upon UV irradiation for 5h in the presence of 100mg of each of these photocatalysts. The removal of 99.6% of the MTBE was achieved with the ceria-ZnO catalyst doped with 1% Pd. In addition to the Pd loading, the N2 sorptiometry study introduced other factors that might affect the catalytic efficiency is the catalyst average pore sizes. The photoreaction was determined to be a first order reaction.
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Affiliation(s)
- Zaki S Seddigi
- Chemistry Department, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Ali Bumajdad
- Chemistry Department, Faculty of Science, Kuwait University, Kuwait
| | - Shahid P Ansari
- Chemistry Department, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Saleh A Ahmed
- Chemistry Department, Umm Al-Qura University, Makkah, Saudi Arabia.
| | - Ekram Y Danish
- Chemistry Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Shakeel Ahmed
- Center for Refining & Petrochemicals, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia
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Gift JS, Caldwell JC, Jinot J, Evans MV, Cote I, Vandenberg JJ. Scientific considerations for evaluating cancer bioassays conducted by the Ramazzini Institute. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:1253-63. [PMID: 24045135 PMCID: PMC3852791 DOI: 10.1289/ehp.1306661] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 09/13/2013] [Indexed: 05/05/2023]
Abstract
BACKGROUND The Ramazzini Institute (RI) has completed nearly 400 cancer bioassays on > 200 compounds. The European Food Safety Authority (EFSA) and others have suggested that study design and protocol differences between the RI and other laboratories by may contribute to controversy regarding cancer hazard findings, principally findings on lymphoma/leukemia diagnoses. OBJECTIVE We aimed to evaluate RI study design, protocol differences, and accuracy of tumor diagnoses for their impact on carcinogenic hazard characterization. METHODS We analyzed the findings from a recent Pathology Working Group (PWG) review of RI procedures and tumor diagnoses, evaluated consistency of RI and other laboratory findings for chemicals identified by the RI as positive for lymphoma/leukemia, and examined evidence for a number of other issues raised regarding RI bioassays. The RI cancer bioassay design and protocols were evaluated in the context of relevant risk assessment guidance from international authorities. DISCUSSION Although the PWG identified close agreement with RI diagnoses for most tumor types, it did not find close agreement for lymphoma/leukemia of the respiratory tract or for neoplasms of the inner ear and cranium. Here we discuss a) the implications of the PWG findings, particularly lymphoma diagnostic issues; b) differences between RI studies and those from other laboratories that are relevant to evaluating RI cancer bioassays; and c) future work that may help resolve some concerns. CONCLUSIONS We concluded that a) issues related to respiratory tract infections have complicated diagnoses at that site (i.e., lymphoma/leukemia), as well as for neoplasms of the inner ear and cranium, and b) there is consistency and value in RI studies for identification of other chemical-related neoplasia.
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Affiliation(s)
- Jeffrey S Gift
- National Center for Environmental Assessment, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA
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