1
|
Jokipii Krueger CC, Moran E, Tessier KM, Tretyakova NY. Isotope Labeling Mass Spectrometry to Quantify Endogenous and Exogenous DNA Adducts and Metabolites of 1,3-Butadiene In Vivo. Chem Res Toxicol 2023; 36:1409-1418. [PMID: 37477250 PMCID: PMC11009968 DOI: 10.1021/acs.chemrestox.3c00141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Human exposure to known carcinogen 1,3-butadiene (BD) is common due to its high concentrations in automobile exhaust, cigarette smoke, and forest fires, as well as its widespread use in the polymer industry. The adverse health effects of BD are mediated by epoxide metabolites such as 3,4-epoxy-1-butene (EB), which reacts with DNA to form 1-hydroxyl-3-buten-1-yl adducts on DNA nucleobases. EB-derived mercapturic acids (1- and 2-(N-acetyl-l-cysteine-S-yl)-1-hydroxybut-3-ene (MHBMA) and N-acetyl-S-(3,4-dihydroxybutyl)-l-cysteine (DHBMA)) and urinary N7-(1-hydroxyl-3-buten-1-yl) guanine DNA adducts (EB-GII) have been used as biomarkers of BD exposure and cancer risk in smokers and occupationally exposed workers. However, low but significant levels of MHBMA, DHBMA, and EB-GII have been reported in unexposed cultured cells, animals, and humans, suggesting that these metabolites and adducts may form endogenously and complicate risk assessment of butadiene exposure. In the present work, stable isotope labeling in combination with high-resolution mass spectrometry was employed to accurately quantify endogenous and exogenous butadiene metabolites and DNA adducts in vivo. Laboratory rats were exposed to 0.3, 0.5, or 3 ppm of BD-d6 by inhalation, and the amounts of endogenous (d0) and exogenous (d6) DNA adducts and metabolites were quantified in tissues and urine by isotope dilution capillary liquid chromatography/high resolution electrospray ionization tandem mass spectrometry (capLC-ESI-HRMS/MS). Our results reveal that EB-GII adducts and MHBMA originate exclusively from exogenous exposure to BD, while substantial amounts of DHBMA are formed endogenously. Urinary EB-GII concentrations were associated with genomic EB-GII levels in tissues of the same animals. Our findings confirm that EB-GII and MHBMA are specific biomarkers of exposure to BD, while endogenous DHBMA predominates at sub-ppm exposures to BD.
Collapse
Affiliation(s)
- Caitlin C. Jokipii Krueger
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Erik Moran
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Katelyn M. Tessier
- Masonic Cancer Center, Biostatistics Core, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Natalia Y. Tretyakova
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| |
Collapse
|
2
|
Richtwerte für Methanol in der Innenraumluft. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2022; 65:128-136. [PMID: 34985598 DOI: 10.1007/s00103-021-03461-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
3
|
Gentry R, Thompson CM, Franzen A, Salley J, Albertini R, Lu K, Greene T. Using mechanistic information to support evidence integration and synthesis: a case study with inhaled formaldehyde and leukemia. Crit Rev Toxicol 2021; 50:885-918. [PMID: 33538218 DOI: 10.1080/10408444.2020.1854678] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Formaldehyde is one of the most comprehensively studied chemicals, with over 30 years of research focused on understanding the development of cancer following inhalation. The causal conclusions regarding the potential for leukemia are largely based on the epidemiological literature, with little consideration of cancer bioassays, dosimetry studies, and mechanistic research, which challenge the biological plausibility of the disease. Recent reanalyzes of the epidemiological literature have also raised significant questions related to the purported associations between formaldehyde and leukemia. Because of this, considerable scientific debate and uncertainty remain on whether there is a causal association between formaldehyde inhalation exposure and leukemia. Further complexity in evaluating this association is related to the endogenous production of formaldehyde. Multiple modes of action (MOA) have been postulated for the development of leukemia following formaldehyde inhalation that includes unsupported hypotheses of direct or indirect toxicity to the target cell population. Herein, the available evidence relevant to evaluating the postulated MOAs for leukemia following formaldehyde inhalation exposure is organized in the IPCS MOA Framework. The integration of all the available evidence clearly highlights the limited amount of data that support any of the postulated MOAs and demonstrates a significant amount of research supporting the null hypothesis that there is no causal association between formaldehyde inhalation exposure and leukemia. These analyses result in a lack of confidence in any of the postulated MOAs, increasing confidence in the conclusion that there is a lack of biological plausibility for a causal association between formaldehyde inhalation exposure and leukemia.
Collapse
Affiliation(s)
| | | | | | | | - Richard Albertini
- Independent Consultant, Emeritus Professor, University of Vermont, Burlington, Vermont, USA
| | - Kun Lu
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | | |
Collapse
|
4
|
Prasad R, Horton JK, Wilson SH. WITHDRAWN: Requirements for PARP-1 covalent crosslinking to DNA (PARP-1 DPC). DNA Repair (Amst) 2020; 89:102824. [PMID: 32151818 DOI: 10.1016/j.dnarep.2020.102824] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/13/2020] [Accepted: 02/16/2020] [Indexed: 02/06/2023]
Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published in DNA Repair, 90C (2020) 102850, https://doi.org/10.1016/j.dnarep.2020.102850. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
Collapse
Affiliation(s)
- Rajendra Prasad
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Julie K Horton
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA.
| |
Collapse
|
5
|
Prasad R, Horton JK, Wilson SH. Requirements for PARP-1 covalent crosslinking to DNA (PARP-1 DPC). DNA Repair (Amst) 2020; 90:102850. [PMID: 32438305 DOI: 10.1016/j.dnarep.2020.102850] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/13/2020] [Accepted: 02/16/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Rajendra Prasad
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, North Carolina, 27709, USA
| | - Julie K Horton
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, North Carolina, 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, North Carolina, 27709, USA.
| |
Collapse
|
6
|
Birkett N, Al-Zoughool M, Bird M, Baan RA, Zielinski J, Krewski D. Overview of biological mechanisms of human carcinogens. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2019; 22:288-359. [PMID: 31631808 DOI: 10.1080/10937404.2019.1643539] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This review summarizes the carcinogenic mechanisms for 109 Group 1 human carcinogens identified as causes of human cancer through Volume 106 of the IARC Monographs. The International Agency for Research on Cancer (IARC) evaluates human, experimental and mechanistic evidence on agents suspected of inducing cancer in humans, using a well-established weight of evidence approach. The monographs provide detailed mechanistic information about all carcinogens. Carcinogens with closely similar mechanisms of action (e.g. agents emitting alpha particles) were combined into groups for the review. A narrative synopsis of the mechanistic profiles for the 86 carcinogens or carcinogen groups is presented, based primarily on information in the IARC monographs, supplemented with a non-systematic review. Most carcinogens included a genotoxic mechanism.
Collapse
Affiliation(s)
- Nicholas Birkett
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario, Canada
- McLaughlin Centre for Population Health Risk Assessment, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Mustafa Al-Zoughool
- Department of Community and Environmental Health, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Michael Bird
- McLaughlin Centre for Population Health Risk Assessment, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Robert A Baan
- International Agency for Research on Cancer, Lyon, France
| | - Jan Zielinski
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario, Canada
- McLaughlin Centre for Population Health Risk Assessment, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Daniel Krewski
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario, Canada
- McLaughlin Centre for Population Health Risk Assessment, Faculty of Medicine, University of Ottawa, Ottawa, Canada
- Risk Sciences International, Ottawa, Canada
| |
Collapse
|
7
|
Xiong J, Ye TT, Ma CJ, Cheng QY, Yuan BF, Feng YQ. N 6-Hydroxymethyladenine: a hydroxylation derivative of N6-methyladenine in genomic DNA of mammals. Nucleic Acids Res 2019; 47:1268-1277. [PMID: 30517733 PMCID: PMC6379677 DOI: 10.1093/nar/gky1218] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/04/2018] [Accepted: 11/22/2018] [Indexed: 12/19/2022] Open
Abstract
In addition to DNA cytosine methylation (5-methyl-2′-deoxycytidine, m5dC), DNA adenine methylation (N6-methyl-2′-deoxyadenosine, m6dA) is another DNA modification that has been discovered in eukaryotes. Recent studies demonstrated that the content and distribution of m6dA in genomic DNA of vertebrates and mammals exhibit dynamic regulation, indicating m6dA may function as a potential epigenetic mark in DNA of eukaryotes besides m5dC. Whether m6dA undergoes the further oxidation in a similar way to m5dC remains elusive. Here, we reported the existence of a new DNA modification, N6-hydroxymethyl-2′-deoxyadenosine (hm6dA), in genomic DNA of mammalian cells and tissues. We found that hm6dA can be formed from the hydroxylation of m6dA by the Fe2+- and 2-oxoglutarate-dependent ALKBH1 protein in genomic DNA of mammals. In addition, the content of hm6dA exhibited significant increase in lung carcinoma tissues. The increased expression of ALKBH1 in lung carcinoma tissues may contribute to the increase of hm6dA in DNA. Taken together, our study reported the existence and formation of hm6dA in genomic DNA of mammals.
Collapse
Affiliation(s)
- Jun Xiong
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| | - Tian-Tian Ye
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| | - Cheng-Jie Ma
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| | - Qing-Yun Cheng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| | - Bi-Feng Yuan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| | - Yu-Qi Feng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China
| |
Collapse
|
8
|
Andersen ME, Gentry PR, Swenberg JA, Mundt KA, White KW, Thompson C, Bus J, Sherman JH, Greim H, Bolt H, Marsh GM, Checkoway H, Coggon D, Clewell HJ. Considerations for refining the risk assessment process for formaldehyde: Results from an interdisciplinary workshop. Regul Toxicol Pharmacol 2019; 106:210-223. [PMID: 31059732 DOI: 10.1016/j.yrtph.2019.04.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/17/2019] [Accepted: 04/21/2019] [Indexed: 01/06/2023]
Abstract
Anticipating the need to evaluate and integrate scientific evidence to inform new risk assessments or to update existing risk assessments, the Formaldehyde Panel of the American Chemistry Council (ACC), in collaboration with the University of North Carolina, convened a workshop: "Understanding Potential Human Health Cancer Risk - From Data Integration to Risk Evaluation" in October 2017. Twenty-four (24) invited-experts participated with expertise in epidemiology, toxicology, science integration and risk evaluation. Including members of the organizing committee, there were 29 participants. The meeting included eleven presentations encompassing an introduction and three sessions: (1) "integrating the formaldehyde science on nasal/nasopharyngeal carcinogenicity and potential for causality"; (2) "integrating the formaldehyde science on lymphohematopoietic cancer and potential for causality; and, (3) "formaldehyde research-data suitable for risk assessment". Here we describe key points from the presentations on epidemiology, toxicology and mechanistic studies that should inform decisions about the potential carcinogenicity of formaldehyde in humans and the discussions about approaches for structuring an integrated, comprehensive risk assessment for formaldehyde. We also note challenges expected when attempting to reconcile divergent results observed from research conducted within and across different scientific disciplines - especially toxicology and epidemiology - and in integrating diverse, multi-disciplinary mechanistic evidence.
Collapse
Affiliation(s)
- Melvin E Andersen
- ScitoVation LLC, 100 Capitola Drive, Drive 106, Durham, NC, 27713, USA.
| | | | - James A Swenberg
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Kenneth A Mundt
- Ramboll US Corporation, Amherst, MA (currently with Cardno Chemrisk, Boston, MA, USA
| | | | | | - James Bus
- Center for Toxicology and Mechanistic Biology, Exponent, Alexandria, VA, USA
| | | | | | - Hermann Bolt
- Leibniz Institute for Working Environment and Human Factors (IfADo), Dortmund, Germany
| | - Gary M Marsh
- Department of Biostatistics, Center for Occupational Biostatistics and Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Harvey Checkoway
- University of California, San Diego, Department of Family Medicine and Public Health, USA
| | - David Coggon
- MRC Lifecourse Epidemiology Unit, University of Southampton, United Kingdom
| | - Harvey J Clewell
- Ramboll US Corporation, 6 Davis Drive, Suite 13, Research Triangle Park, NC, 27709, USA
| |
Collapse
|
9
|
Prasad R, Horton JK, Dai DP, Wilson SH. Repair pathway for PARP-1 DNA-protein crosslinks. DNA Repair (Amst) 2018; 73:71-77. [PMID: 30466837 DOI: 10.1016/j.dnarep.2018.11.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/03/2018] [Accepted: 11/09/2018] [Indexed: 02/06/2023]
Abstract
Poly(ADP-ribose) polymerase-1 (PARP-1) is a regulatory enzyme involved in many different processes of DNA and RNA metabolism, including DNA repair. Previously, PARP-1 was found capable of forming a covalent DNA-protein crosslink (DPC) at the apurinic/apyrimidinic (AP) site in double-stranded DNA. The C1´ atom of the AP site participates in Schiff base formation with a lysine side chain in PARP-1, and a covalent bond is formed upon reduction of the Schiff base. The PARP-1 DPC is formed in vivo where DPC formation correlates with AP site induction by a monofunctional alkylating agent. Here, we examined repair of PARP-1 DPCs in mouse fibroblasts and found that a proteasome inhibitor, MG-132, reduces repair resulting in accumulation of PARP-1 DPCs and increased alkylating agent cytotoxicity. Using a model DNA substrate mimicking the PARP-1 DPC after proteasomal degradation, we found that repair is completed by a sub-pathway of base excision repair (BER). Tyrosyl-DNA phosphodiesterase 1 was proficient in removing the ring-open AP site sugar at the phosphodiester linkage, leaving an intermediate for processing by other BER enzymes. The results reveal proteasomal degradation of the PARP-1 DPC is active in mouse fibroblasts and that a model repair intermediate is processed by the BER machinery.
Collapse
Affiliation(s)
- Rajendra Prasad
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Julie K Horton
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Da-Peng Dai
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA.
| |
Collapse
|
10
|
Lee HW, Park SH, Weng MW, Wang HT, Huang WC, Lepor H, Wu XR, Chen LC, Tang MS. E-cigarette smoke damages DNA and reduces repair activity in mouse lung, heart, and bladder as well as in human lung and bladder cells. Proc Natl Acad Sci U S A 2018; 115:E1560-E1569. [PMID: 29378943 PMCID: PMC5816191 DOI: 10.1073/pnas.1718185115] [Citation(s) in RCA: 188] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
E-cigarette smoke delivers stimulant nicotine as aerosol without tobacco or the burning process. It contains neither carcinogenic incomplete combustion byproducts nor tobacco nitrosamines, the nicotine nitrosation products. E-cigarettes are promoted as safe and have gained significant popularity. In this study, instead of detecting nitrosamines, we directly measured DNA damage induced by nitrosamines in different organs of E-cigarette smoke-exposed mice. We found mutagenic O6-methyldeoxyguanosines and γ-hydroxy-1,N2 -propano-deoxyguanosines in the lung, bladder, and heart. DNA-repair activity and repair proteins XPC and OGG1/2 are significantly reduced in the lung. We found that nicotine and its metabolite, nicotine-derived nitrosamine ketone, can induce the same effects and enhance mutational susceptibility and tumorigenic transformation of cultured human bronchial epithelial and urothelial cells. These results indicate that nicotine nitrosation occurs in vivo in mice and that E-cigarette smoke is carcinogenic to the murine lung and bladder and harmful to the murine heart. It is therefore possible that E-cigarette smoke may contribute to lung and bladder cancer, as well as heart disease, in humans.
Collapse
Affiliation(s)
- Hyun-Wook Lee
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987
| | - Sung-Hyun Park
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987
| | - Mao-Wen Weng
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987
| | - Hsiang-Tsui Wang
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987
| | - William C Huang
- Department of Urology, New York University School of Medicine, New York, NY 10016
| | - Herbert Lepor
- Department of Urology, New York University School of Medicine, New York, NY 10016
| | - Xue-Ru Wu
- Department of Urology, New York University School of Medicine, New York, NY 10016
| | - Lung-Chi Chen
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987
| | - Moon-Shong Tang
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo Park, NY 10987;
| |
Collapse
|
11
|
King T, Cole M, Farber JM, Eisenbrand G, Zabaras D, Fox EM, Hill JP. Food safety for food security: Relationship between global megatrends and developments in food safety. Trends Food Sci Technol 2017. [DOI: 10.1016/j.tifs.2017.08.014] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
12
|
Nielsen GD, Larsen ST, Wolkoff P. Re-evaluation of the WHO (2010) formaldehyde indoor air quality guideline for cancer risk assessment. Arch Toxicol 2017; 91:35-61. [PMID: 27209488 PMCID: PMC5225186 DOI: 10.1007/s00204-016-1733-8] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 04/27/2016] [Indexed: 11/11/2022]
Abstract
In 2010, the World Health Organization (WHO) established an indoor air quality guideline for short- and long-term exposures to formaldehyde (FA) of 0.1 mg/m3 (0.08 ppm) for all 30-min periods at lifelong exposure. This guideline was supported by studies from 2010 to 2013. Since 2013, new key studies have been published and key cancer cohorts have been updated, which we have evaluated and compared with the WHO guideline. FA is genotoxic, causing DNA adduct formation, and has a clastogenic effect; exposure-response relationships were nonlinear. Relevant genetic polymorphisms were not identified. Normal indoor air FA concentrations do not pass beyond the respiratory epithelium, and therefore FA's direct effects are limited to portal-of-entry effects. However, systemic effects have been observed in rats and mice, which may be due to secondary effects as airway inflammation and (sensory) irritation of eyes and the upper airways, which inter alia decreases respiratory ventilation. Both secondary effects are prevented at the guideline level. Nasopharyngeal cancer and leukaemia were observed inconsistently among studies; new updates of the US National Cancer Institute (NCI) cohort confirmed that the relative risk was not increased with mean FA exposures below 1 ppm and peak exposures below 4 ppm. Hodgkin's lymphoma, not observed in the other studies reviewed and not considered FA dependent, was increased in the NCI cohort at a mean concentration ≥0.6 mg/m3 and at peak exposures ≥2.5 mg/m3; both levels are above the WHO guideline. Overall, the credibility of the WHO guideline has not been challenged by new studies.
Collapse
Affiliation(s)
- Gunnar Damgård Nielsen
- National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen, Denmark.
| | - Søren Thor Larsen
- National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen, Denmark
| | - Peder Wolkoff
- National Research Centre for the Working Environment, Lersø Parkallé 105, 2100, Copenhagen, Denmark
| |
Collapse
|
13
|
Zendehdel R, Fazli Z, Mazinani M. Neurotoxicity effect of formaldehyde on occupational exposure and influence of individual susceptibility to some metabolism parameters. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:648. [PMID: 27796833 DOI: 10.1007/s10661-016-5662-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 10/21/2016] [Indexed: 06/06/2023]
Abstract
Over the years, neurotoxicity and cognitive dysfunction have separately been associated with endogenous formaldehyde and reduction of acetylcholine signals. However, a limited number of studies have shown a relationship between cholinergic neurotransmitter and formaldehyde exposure. Therefore, the aim of this study was to assess the neurological effect on workers from melamine-dish preparation workshop, who were exposed to formaldehyde. A total of 35 formaldehyde-exposed workers were compared with 32 control employees from the food industry. Occupational exposure to formaldehyde was conducted using the National Institute of Occupational Safety and Health 3500 methods. Using the Ellman method, acetylcholinesterase (AChE) as a biomarker for neurotoxicity was analyzed in blood erythrocyte. The effects of alcohol dehydrogenase III (ADH3) and Mn-superoxide dismutase (Mn-SOD) polymorphism were used to survey the level of AChE activity. In this study, it was found that exposure to airborne formaldehyde increased from 0.024 to 0.74 ppm and the median personnel exposure was 0.057. Induction of AChE activity was observed in formaldehyde-exposed workers as compared with the control group (p < 0.01), while AChE activity increased in 64 % of the exposed subjects. Spearman's correlation (p < 0.02) was used to evaluate the association between AChE activity and occupational exposure to formaldehyde. Exposed subjects containing ADH32-2 genotype had higher AChE than others. The findings of this study suggest that the neurotoxic effect of formaldehyde depends on the AChE activity, which is affected by metabolism. It can be concluded that cholinergic signal reduction in cases of cognitive dysfunction could be associated with endogenous formaldehyde.
Collapse
Affiliation(s)
- Rezvan Zendehdel
- Safety Promotion and Injury Preventation Research Centre, Beheshti University of Medical Sciences, Tehran, Iran.
- Department of Occupational Hygiene, School of Public Health, Shahid Beheshti University, Tehran, Iran.
| | - Zohreh Fazli
- Department of Occupational Hygiene, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Mazinani
- Department of Occupational Hygiene, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
14
|
Abstract
In this review, current issues and opportunities in food safety assessment are discussed. Food safety is considered an essential element inherent in global food security. Hazard characterization is pivotal within the continuum of risk assessment, but it may be conceived only within a very limited frame as a true alternative to risk assessment. Elucidation of the mode of action underlying a given hazard is vital to create a plausible basis for human toxicology evaluation. Risk assessment, to convey meaningful risk communication, must be based on appropriate and reliable consideration of both exposure and mode of action. New perspectives, provided by monitoring human exogenous and endogenous exposure biomarkers, are considered of great promise to support classical risk extrapolation from animal toxicology.
Collapse
Affiliation(s)
- G Eisenbrand
- Division of Food Chemistry and Toxicology, Department of Chemistry, University of Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
15
|
Albertini RJ, Kaden DA. Do chromosome changes in blood cells implicate formaldehyde as a leukemogen? Crit Rev Toxicol 2016; 47:145-184. [DOI: 10.1080/10408444.2016.1211987] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
16
|
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.
Collapse
|
17
|
de Medeiros IC, de Lima JG. Is nonalcoholic fatty liver disease an endogenous alcoholic fatty liver disease? – A mechanistic hypothesis. Med Hypotheses 2015; 85:148-52. [DOI: 10.1016/j.mehy.2015.04.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 04/11/2015] [Accepted: 04/21/2015] [Indexed: 02/07/2023]
|
18
|
Nakamura J, Mutlu E, Sharma V, Collins L, Bodnar W, Yu R, Lai Y, Moeller B, Lu K, Swenberg J. The endogenous exposome. DNA Repair (Amst) 2014; 19:3-13. [PMID: 24767943 PMCID: PMC4097170 DOI: 10.1016/j.dnarep.2014.03.031] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The concept of the Exposome is a compilation of diseases and one's lifetime exposure to chemicals, whether the exposure comes from environmental, dietary, or occupational exposures; or endogenous chemicals that are formed from normal metabolism, inflammation, oxidative stress, lipid peroxidation, infections, and other natural metabolic processes such as alteration of the gut microbiome. In this review, we have focused on the endogenous exposome, the DNA damage that arises from the production of endogenous electrophilic molecules in our cells. It provides quantitative data on endogenous DNA damage and its relationship to mutagenesis, with emphasis on when exogenous chemical exposures that produce identical DNA adducts to those arising from normal metabolism cause significant increases in total identical DNA adducts. We have utilized stable isotope labeled chemical exposures of animals and cells, so that accurate relationships between endogenous and exogenous exposures can be determined. Advances in mass spectrometry have vastly increased both the sensitivity and accuracy of such studies. Furthermore, we have clear evidence of which sources of exposure drive low dose biology that results in mutations and disease. These data provide much needed information to impact quantitative risk assessments, in the hope of moving towards the use of science, rather than default assumptions.
Collapse
Affiliation(s)
- Jun Nakamura
- University of North Carolina, Chapel Hill, NC, United States
| | - Esra Mutlu
- University of North Carolina, Chapel Hill, NC, United States
| | - Vyom Sharma
- University of North Carolina, Chapel Hill, NC, United States
| | - Leonard Collins
- University of North Carolina, Chapel Hill, NC, United States
| | - Wanda Bodnar
- University of North Carolina, Chapel Hill, NC, United States
| | - Rui Yu
- University of North Carolina, Chapel Hill, NC, United States
| | - Yongquan Lai
- University of North Carolina, Chapel Hill, NC, United States
| | - Benjamin Moeller
- University of North Carolina, Chapel Hill, NC, United States; Lovelace Respiratory Research Institute, Albuquerque, NM, United States
| | - Kun Lu
- University of North Carolina, Chapel Hill, NC, United States
| | - James Swenberg
- University of North Carolina, Chapel Hill, NC, United States.
| |
Collapse
|
19
|
Siu MT, Shapiro AM, Wiley MJ, Wells PG. A role for glutathione, independent of oxidative stress, in the developmental toxicity of methanol. Toxicol Appl Pharmacol 2013; 273:508-15. [PMID: 24095963 DOI: 10.1016/j.taap.2013.09.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 09/06/2013] [Accepted: 09/23/2013] [Indexed: 10/26/2022]
Abstract
Oxidative stress and reactive oxygen species (ROS) have been implicated in the teratogenicity of methanol (MeOH) in rodents, both in vivo and in embryo culture. We explored the ROS hypothesis further in vivo in pregnant C57BL/6J mice. Following maternal treatment with a teratogenic dose of MeOH, 4 g/kg via intraperitoneal (ip) injection on gestational day (GD) 12, there was no increase 6h later in embryonic ROS formation, measured by 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) fluorescence, despite an increase observed with the positive control ethanol (EtOH), nor was there an increase in embryonic oxidatively damaged DNA, quantified as 8-oxo-2'-deoxyguanosine (8-oxodG) formation. MeOH teratogenicity (primarily ophthalmic anomalies, cleft palate) also was not altered by pre- and post-treatment with varying doses of the free radical spin trapping agent alpha-phenyl-N-tert-butylnitrone (PBN). In contrast, pretreatment with L-buthionine-(S,R)-sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, depleted maternal hepatic and embryonic GSH, and enhanced some new anomalies (micrognathia, agnathia, short snout, fused digits, cleft lip, low set ears), but not the most common teratogenic effects of MeOH (ophthalmic anomalies, cleft palate) in this strain. These results suggest that ROS did not contribute to the teratogenic effects of MeOH in this in vivo mouse model, in contrast to results in embryo culture from our laboratory, and that the protective effect of GSH in this model may arise from its role as a cofactor for formaldehyde dehydrogenase in the detoxification of formaldehyde.
Collapse
Affiliation(s)
- Michelle T Siu
- Division of Biomolecular Sciences, Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | | | | | | |
Collapse
|