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Mendy A, Burcham S, Merianos AL, Mersha TB, Mahabee-Gittens EM, Chen A, Yolton K. Urinary volatile organic compound metabolites and reduced lung function in U.S. adults. Respir Med 2022; 205:107053. [PMID: 36399896 PMCID: PMC9869342 DOI: 10.1016/j.rmed.2022.107053] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/12/2022]
Abstract
BACKGROUND Volatile organic compounds (VOCs) are associated with adverse respiratory outcomes at high occupational exposures. However, whether exposure levels found in the general population have similar effects is unknown. METHODS We analyzed data on 1342 adult participants in the 2011-2012 National Health and Nutrition Examination Survey aged ≥18 years old who had urinary VOC metabolites and spirometry measurements available. Linear regression models adjusting for covariates were fitted to estimate the associations of VOC exposures levels and spirometry outcomes, while accounting for survey design and sampling weights to generate nationally representative estimates. RESULTS The urinary metabolites for xylene, acrylamide, acrolein, 1,3-butadiene, cyanide, toluene, 1-bromopropane, acrylonitrile, propylene oxide, styrene, ethylbenzene, and crotonaldehyde in our analysis were all detected in >75% of participants. Forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio % was lower with urinary metabolites of acrylamide (β: -2.65, 95% CI: -4.32, -0.98), acrylonitrile (β: -1.02, 95% CI: -2.01, -0.03), and styrene (β: -3.13, 95% CI: -5.35, -0.90). FEV1% predicted was lower with the urinary metabolites of acrolein (β: -7.77, 95% CI: -13.29, -2.25), acrylonitrile (β: -2.05, 95% CI: -3.77, -0.34), propylene oxide (β: -2.90, 95% CI: -5.50, -0.32), and styrene (β: -4.41, 95% CI: -6.97, -1.85). CONCLUSIONS This is the first study of a representative sample of the U.S. adult population to reveal associations of acrylonitrile, propylene oxide, and styrene urinary metabolites with reduced lung function at non-occupational exposures. Results also support previous evidence of acrylamide and acrolein's association with adverse respiratory outcomes.
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Affiliation(s)
- Angelico Mendy
- Division of Epidemiology, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
| | - Sara Burcham
- Division of Epidemiology, Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Ashley L Merianos
- School of Human Services, University of Cincinnati, Cincinnati, OH, USA
| | - Tesfaye B Mersha
- Division of Asthma Research, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - E Melinda Mahabee-Gittens
- Division of Emergency Medicine, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Aimin Chen
- Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kimberley Yolton
- General and Community Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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Pottenger LH, Boysen G, Brown K, Cadet J, Fuchs RP, Johnson GE, Swenberg JA. Understanding the importance of low-molecular weight (ethylene oxide- and propylene oxide-induced) DNA adducts and mutations in risk assessment: Insights from 15 years of research and collaborative discussions. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2019; 60:100-121. [PMID: 30536466 PMCID: PMC6590209 DOI: 10.1002/em.22248] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/10/2018] [Accepted: 08/23/2018] [Indexed: 05/11/2023]
Abstract
The interpretation and significance of DNA adduct data, their causal relationship to mutations, and their role in risk assessment have been debated for many years. An extended effort to identify key questions and collect relevant data to address them was focused on the ubiquitous low MW N7-alkyl/hydroxyalkylguanine adducts. Several academic, governmental, and industrial laboratories collaborated to gather new data aimed at better understanding the role and potential impact of these adducts in quantifiable genotoxic events (gene mutations/micronucleus). This review summarizes and evaluates the status of dose-response data for DNA adducts and mutations from recent experimental work with standard mutagenic agents and ethylene oxide and propylene oxide, and the importance for risk assessment. This body of evidence demonstrates that small N7-alkyl/hydroxyalkylguanine adducts are not pro-mutagenic and, therefore, adduct formation alone is not adequate evidence to support a mutagenic mode of action. Quantitative methods for dose-response analysis and derivation of thresholds, benchmark dose (BMD), or other points-of-departure (POD) for genotoxic events are now available. Integration of such analyses of genetox data is necessary to properly assess any role for DNA adducts in risk assessment. Regulatory acceptance and application of these insights remain key challenges that only the regulatory community can address by applying the many learnings from recent research. The necessary tools, such as BMDs and PODs, and the example datasets, are now available and sufficiently mature for use by the regulatory community. Environ. Mol. Mutagen. 60: 100-121, 2019. © 2018 The Authors. Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.
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Affiliation(s)
- L. H. Pottenger
- Olin Corporation/Blue Cube Operations, LLC, retired, LHP TOX CONSULT, LLCMidlandMIUSA
| | - G. Boysen
- Department of Environmental and Occupational Health and The Winthrop P Rockefeller Cancer Institute University of Arkansas for Medical SciencesLittle RockArkansasUSA
| | - K. Brown
- Leicester Cancer Research CentreUniversity of LeicesterLeicesterUnited Kingdom
| | - J. Cadet
- Institut Nanosciences et Cryogénie, CEA‐GrenobleGrenobleFrance
- Université de SherbrookeSherbrookeCanada
| | - R. P. Fuchs
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068Marseille, 13009France
- CNRS, UMR7258Marseille, 13009France
- Institut Paoli‐CalmettesMarseille, 13009France
- Aix‐Marseille UniversityUM 105, 13284, MarseilleFrance
| | - G. E. Johnson
- Swansea University, Institute of Life SciencesSwanseaUnited Kingdom
| | - J. A. Swenberg
- University of North CarolinaChapel HillNorth CarolinaUSA
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Filser JG, Klein D. A physiologically based toxicokinetic model for inhaled ethylene and ethylene oxide in mouse, rat, and human. Toxicol Lett 2018; 286:54-79. [DOI: 10.1016/j.toxlet.2017.07.896] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 07/20/2017] [Accepted: 07/25/2017] [Indexed: 01/18/2023]
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Kiwamoto R, Ploeg D, Rietjens IMCM, Punt A. Dose-dependent DNA adduct formation by cinnamaldehyde and other food-borne α,β-unsaturated aldehydes predicted by physiologically based in silico modelling. Toxicol In Vitro 2015; 31:114-25. [PMID: 26612355 DOI: 10.1016/j.tiv.2015.11.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 11/15/2015] [Accepted: 11/19/2015] [Indexed: 12/20/2022]
Abstract
Genotoxicity of α,β-unsaturated aldehydes shown in vitro raises a concern for the use of the aldehydes as food flavourings, while at low dose exposures the formation of DNA adducts may be prevented by detoxification. Unlike many α,β-unsaturated aldehydes for which in vivo data are absent, cinnamaldehyde was shown to be not genotoxic or carcinogenic in vivo. The present study aimed at comparing dose-dependent DNA adduct formation by cinnamaldehyde and 18 acyclic food-borne α,β-unsaturated aldehydes using physiologically based kinetic/dynamic (PBK/D) modelling. In rats, cinnamaldehyde was predicted to induce higher DNA adducts levels than 6 out of the 18 α,β-unsaturated aldehydes, indicating that these 6 aldehydes may also test negative in vivo. At the highest cinnamaldehyde dose that tested negative in vivo, cinnamaldehyde was predicted to form at least three orders of magnitude higher levels of DNA adducts than the 18 aldehydes at their respective estimated daily intake. These results suggest that for all the 18 α,β-unsaturated aldehydes DNA adduct formation at doses relevant for human dietary exposure may not raise a concern. The present study illustrates a possible use of physiologically based in silico modelling to facilitate a science-based comparison and read-across on the possible risks posed by DNA reactive agents.
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Affiliation(s)
- R Kiwamoto
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands.
| | - D Ploeg
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - I M C M Rietjens
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - A Punt
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
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Katz I, Murdock J, Palgen M, Pype J, Caillibotte G. Pharmacokinetic analysis of the chronic administration of the inert gases Xe and Ar using a physiological based model. Med Gas Res 2015; 5:8. [PMID: 26113973 PMCID: PMC4480577 DOI: 10.1186/s13618-015-0029-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 05/19/2015] [Indexed: 11/10/2022] Open
Abstract
Background New gas therapies using inert gases such as xenon and argon are being studied, which would require chronically administered repeating doses. The pharmacokinetics of this type of administration has not been addressed in the literature. Methods A physiologically based pharmacokinetics (PBPK) model for humans, pigs, mice, and rats has been developed to investigate the unique aspects of the chronic administration of inert gas therapies. The absorption, distribution, metabolism and excretion (ADME) models are as follows: absorption in all compartments is assumed to be perfusion limited, no metabolism of the gases occurs, and excretion is only the reverse process of absorption through the lungs and exhaled. Results The model has shown that there can be a residual dose, equivalent to constant administration, for chronic repeated dosing of xenon in humans. However, this is not necessarily the case for small animals used in pre-clinical studies. Conclusions The use of standard pharmacokinetics parameters such as area under the curve would be more appropriate to assess the delivered dose of chronic gas administration than the gas concentration in the delivery system that is typically reported in the scientific literature because species and gas differences can result in very different delivered doses.
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Affiliation(s)
- Ira Katz
- Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, 1, chemin de la Porte des Loges, BP126 - 78354 Jouy en Josas, France ; Department of Mechanical Engineering, Lafayette College, Easton, PA 18042 USA
| | - Jacqueline Murdock
- Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, 1, chemin de la Porte des Loges, BP126 - 78354 Jouy en Josas, France
| | - Marc Palgen
- Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, 1, chemin de la Porte des Loges, BP126 - 78354 Jouy en Josas, France
| | - Jan Pype
- Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, 1, chemin de la Porte des Loges, BP126 - 78354 Jouy en Josas, France
| | - Georges Caillibotte
- Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, 1, chemin de la Porte des Loges, BP126 - 78354 Jouy en Josas, France
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Kiwamoto R, Spenkelink A, Rietjens IMCM, Punt A. An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes. Toxicol Appl Pharmacol 2014; 282:108-17. [PMID: 25448044 DOI: 10.1016/j.taap.2014.10.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 10/08/2014] [Accepted: 10/21/2014] [Indexed: 12/27/2022]
Abstract
Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure-activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment.
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Affiliation(s)
- R Kiwamoto
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands.
| | - A Spenkelink
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - I M C M Rietjens
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - A Punt
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
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Brüning T, Bartsch R, Bolt HM, Desel H, Drexler H, Gundert-Remy U, Hartwig A, Jäckh R, Leibold E, Pallapies D, Rettenmeier AW, Schlüter G, Stropp G, Sucker K, Triebig G, Westphal G, van Thriel C. Sensory irritation as a basis for setting occupational exposure limits. Arch Toxicol 2014; 88:1855-79. [PMID: 25182421 PMCID: PMC4161939 DOI: 10.1007/s00204-014-1346-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/21/2014] [Indexed: 02/06/2023]
Abstract
There is a need of guidance on how local irritancy data should be incorporated into risk assessment procedures, particularly with respect to the derivation of occupational exposure limits (OELs). Therefore, a board of experts from German committees in charge of the derivation of OELs discussed the major challenges of this particular end point for regulatory toxicology. As a result, this overview deals with the question of integrating results of local toxicity at the eyes and the upper respiratory tract (URT). Part 1 describes the morphology and physiology of the relevant target sites, i.e., the outer eye, nasal cavity, and larynx/pharynx in humans. Special emphasis is placed on sensory innervation, species differences between humans and rodents, and possible effects of obnoxious odor in humans. Based on this physiological basis, Part 2 describes a conceptual model for the causation of adverse health effects at these targets that is composed of two pathways. The first, “sensory irritation” pathway is initiated by the interaction of local irritants with receptors of the nervous system (e.g., trigeminal nerve endings) and a downstream cascade of reflexes and defense mechanisms (e.g., eyeblinks, coughing). While the first stages of this pathway are thought to be completely reversible, high or prolonged exposure can lead to neurogenic inflammation and subsequently tissue damage. The second, “tissue irritation” pathway starts with the interaction of the local irritant with the epithelial cell layers of the eyes and the URT. Adaptive changes are the first response on that pathway followed by inflammation and irreversible damages. Regardless of these initial steps, at high concentrations and prolonged exposures, the two pathways converge to the adverse effect of morphologically and biochemically ascertainable changes. Experimental exposure studies with human volunteers provide the empirical basis for effects along the sensory irritation pathway and thus, “sensory NOAEChuman” can be derived. In contrast, inhalation studies with rodents investigate the second pathway that yields an “irritative NOAECanimal.” Usually the data for both pathways is not available and extrapolation across species is necessary. Part 3 comprises an empirical approach for the derivation of a default factor for interspecies differences. Therefore, from those substances under discussion in German scientific and regulatory bodies, 19 substances were identified known to be human irritants with available human and animal data. The evaluation started with three substances: ethyl acrylate, formaldehyde, and methyl methacrylate. For these substances, appropriate chronic animal and a controlled human exposure studies were available. The comparison of the sensory NOAEChuman with the irritative NOAECanimal (chronic) resulted in an interspecies extrapolation factor (iEF) of 3 for extrapolating animal data concerning local sensory irritating effects. The adequacy of this iEF was confirmed by its application to additional substances with lower data density (acetaldehyde, ammonia, n-butyl acetate, hydrogen sulfide, and 2-ethylhexanol). Thus, extrapolating from animal studies, an iEF of 3 should be applied for local sensory irritants without reliable human data, unless individual data argue for a substance-specific approach.
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Affiliation(s)
- Thomas Brüning
- Institute for Prevention and Occupational Medicine of the German Social Accident Insurance (IPA), Bochum, Germany,
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A physiologically based in silico model for trans-2-hexenal detoxification and DNA adduct formation in human including interindividual variation indicates efficient detoxification and a negligible genotoxicity risk. Arch Toxicol 2013; 87:1725-37. [PMID: 23864024 DOI: 10.1007/s00204-013-1091-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/02/2013] [Indexed: 12/23/2022]
Abstract
A number of α,β-unsaturated aldehydes are present in food both as natural constituents and as flavouring agents. Their reaction with DNA due to their electrophilic α,β-unsaturated aldehyde moiety may result in genotoxicity as observed in some in vitro models, thereby raising a safety concern. A question that remains is whether in vivo detoxification would be efficient enough to prevent DNA adduct formation and genotoxicity. In this study, a human physiologically based kinetic/dynamic (PBK/D) model of trans-2-hexenal (2-hexenal), a selected model α,β-unsaturated aldehyde, was developed to examine dose-dependent detoxification and DNA adduct formation in humans upon dietary exposure. The kinetic model parameters for detoxification were quantified using relevant pooled human tissue fractions as well as tissue fractions from 11 different individual subjects. In addition, a Monte Carlo simulation was performed so that the impact of interindividual variation in 2-hexenal detoxification on the DNA adduct formation in the population as a whole could be examined. The PBK/D model revealed that DNA adduct formation due to 2-hexenal exposure was 0.039 adducts/10⁸ nucleotides (nt) at the estimated average 2-hexenal dietary intake (0.04 mg 2-hexenal/kg bw) and 0.18 adducts/10⁸ nt at the 95th percentile of the dietary intake (0.178 mg 2-hexenal/kg bw) in the most sensitive people. These levels are three orders of magnitude lower than natural background DNA adduct levels that have been reported in disease-free humans (6.8-110 adducts/10⁸ nt), suggesting that the genotoxicity risk for the human population at realistic dietary daily intakes of 2-hexenal may be negligible.
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Kiwamoto R, Rietjens IMCM, Punt A. A Physiologically Based in Silico Model for trans-2-Hexenal Detoxification and DNA Adduct Formation in Rat. Chem Res Toxicol 2012; 25:2630-41. [DOI: 10.1021/tx3002669] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Reiko Kiwamoto
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen,
The Netherlands
| | | | - Ans Punt
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen,
The Netherlands
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Martin SA, Campbell JL, Tremblay RT, Fisher JW. Development of a physiologically based pharmacokinetic model for inhalation of jet fuels in the rat. Inhal Toxicol 2011; 24:1-26. [DOI: 10.3109/08958378.2011.631297] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Li Q, Csanády GA, Kessler W, Klein D, Pankratz H, Pütz C, Richter N, Filser JG. Kinetics of ethylene and ethylene oxide in subcellular fractions of lungs and livers of male B6C3F1 mice and male fischer 344 rats and of human livers. Toxicol Sci 2011; 123:384-98. [PMID: 21785163 PMCID: PMC3179684 DOI: 10.1093/toxsci/kfr194] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 07/13/2011] [Indexed: 12/01/2022] Open
Abstract
Ethylene (ET) is metabolized in mammals to the carcinogenic ethylene oxide (EO). Although both gases are of high industrial relevance, only limited data exist on the toxicokinetics of ET in mice and of EO in humans. Metabolism of ET is related to cytochrome P450-dependent mono-oxygenase (CYP) and of EO to epoxide hydrolase (EH) and glutathione S-transferase (GST). Kinetics of ET metabolism to EO and of elimination of EO were investigated in headspace vessels containing incubations of subcellular fractions of mouse, rat, or human liver or of mouse or rat lung. CYP-associated metabolism of ET and GST-related metabolism of EO were found in microsomes and cytosol, respectively, of each species. EH-related metabolism of EO was not detectable in hepatic microsomes of rats and mice but obeyed saturation kinetics in hepatic microsomes of humans. In ET-exposed liver microsomes, metabolism of ET to EO followed Michaelis-Menten-like kinetics. Mean values of V(max) [nmol/(min·mg protein)] and of the apparent Michaelis constant (K(m) [mmol/l ET in microsomal suspension]) were 0.567 and 0.0093 (mouse), 0.401 and 0.031 (rat), and 0.219 and 0.013 (human). In lung microsomes, V(max) values were 0.073 (mouse) and 0.055 (rat). During ET exposure, the rate of EO production decreased rapidly. By modeling a suicide inhibition mechanism, rate constants for CYP-mediated catalysis and CYP inactivation were estimated. In liver cytosol, mean GST activities to EO expressed as V(max)/K(m) [μl/(min·mg protein)] were 27.90 (mouse), 5.30 (rat), and 1.14 (human). The parameters are most relevant for reducing uncertainties in the risk assessment of ET and EO.
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Affiliation(s)
- Qiang Li
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Institut für Toxikologie und Umwelthygiene, Technische Universität München, D-80802 München, Germany
| | - György András Csanády
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Institut für Toxikologie und Umwelthygiene, Technische Universität München, D-80802 München, Germany
| | - Winfried Kessler
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Dominik Klein
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Institut für Toxikologie und Umwelthygiene, Technische Universität München, D-80802 München, Germany
| | - Helmut Pankratz
- Institut für Rechtsmedizin, Ludwig-Maximilians-Universität München, D-80336 München, Germany
| | - Christian Pütz
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Nadine Richter
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Institut für Toxikologie und Umwelthygiene, Technische Universität München, D-80802 München, Germany
| | - Johannes Georg Filser
- Institute of Toxicology, German Research Center for Environmental Health, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Institut für Toxikologie und Umwelthygiene, Technische Universität München, D-80802 München, Germany
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Csanády GA, Göen T, Klein D, Drexler H, Filser JG. Trichloroacetic acid in urine as biological exposure equivalent for low exposure concentrations of trichloroethene. Arch Toxicol 2010; 84:897-902. [PMID: 20414643 DOI: 10.1007/s00204-010-0540-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 04/01/2010] [Indexed: 10/19/2022]
Abstract
A urinary trichloroacetic acid (TCA) concentration of 100 mg/l at the end of the last work shift (8 h/day, 5 days/week) of the week has been established in workers as exposure equivalent for the carcinogenic substance trichloroethene (EKA for TRI) at an exposure concentration of 50 ppm TRI. Due to the continuous reduction of atmospheric TRI concentrations during the last years, the quantitative relation given by the EKA for TRI is revised for exposures to low TRI concentrations. A physiological two-compartment model is presented by which the urinary TCA concentrations are calculated that result from inhaled TRI in humans. The model contains one compartment for trichloroethanol (TCE) and one for TCA. Inhaled TRI is metabolized to TCA and to TCE. The latter is in part further oxidized to TCA. Urinary elimination of TCA is modeled to obey first order kinetics. All required model parameters were taken form the literature. In order to evaluate the model performance on the urinary TCA excretion at low exposure concentrations, predicted urinary TCA concentrations were compared with data obtained in two volunteer studies and in one field study. The model was evaluated at exposure concentrations as low as 12.5 ppm TRI. It is demonstrated that the correlation described by the hitherto used EKA for TRI is also valid at low TRI concentrations. For TRI exposure concentrations of 0.6 and 6 ppm, the resulting urinary TCA concentrations at the end of the last work shift of a week are predicted to be 1.2 and 12 mg/l, respectively.
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Affiliation(s)
- György A Csanády
- Institute of Toxicology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
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Khan MDH, Klein D, Mossbrugger I, Oesterle D, Csanády GA, Quintanilla-Martinez L, Filser JG. Is propylene oxide induced cell proliferation in rat nasal respiratory epithelium mediated by a severe depletion of water-soluble non-protein thiol? Toxicol Lett 2009; 185:203-10. [PMID: 19382340 DOI: 10.1016/j.toxlet.2009.01.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Propylene oxide (PO) concentrations >or=300 ppm induced cell proliferation and tumors in rat nasal respiratory epithelium (NRE). Cell proliferation was suggested to result from depletion of glutathione (GSH) in NRE. In order to substantiate this hypothesis, cell proliferation - measured by bromodeoxyuridine incorporation into DNA of the epithelium lining middle septum, dorsal medial meatus, and medial and lateral surfaces of the nasoturbinate in transverse nasal sections taken immediately posterior to the upper incisor teeth - and water-soluble non-protein thiol (NPSH) in NRE were determined after exposing male Fischer 344 rats to 50 ppm, 100 ppm, 200 ppm, or 300 ppm PO (6 h/day, 3 days). Both parameters were also investigated after treating rats for 3 days with diethylmaleate (DEM; 2 x 250 mg/kg/day or 500 + 150 mg/kg/day) or buthionine sulfoximine (BSO; 500 mg/kg/day). Exposure to 50 ppm PO and treatment with 2 x2 50 mg/kg/day DEM resulted in NPSH levels approximating 50% and 80% of the level in untreated controls, respectively. Cell proliferation did not increase. After exposures to >or= 100 ppm PO or treatment with BSO or 500 + 150 mg/kg/day DEM, NPSH was depleted to <or=1/3 of the control level and cell proliferation increased 2.0-3.7-fold the control value. In conclusion, profound perturbation of the GSH status may represent a crucial step in PO induced rat nasal tumorigenicity.
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Affiliation(s)
- Mohammad D H Khan
- Institute of Toxicology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany
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Sweeney LM, Kirman CR, Albertini RJ, Tan YM, Clewell HJ, Filser JG, Csanády G, Pottenger LH, Banton MI, Graham CJ, Andrews LS, Papciak RJ, Gargas ML. Derivation of inhalation toxicity reference values for propylene oxide using mode of action analysis: Example of a threshold carcinogen. Crit Rev Toxicol 2009; 39:462-86. [DOI: 10.1080/10408440902837959] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Development of good modelling practice for physiologically based pharmacokinetic models for use in risk assessment: The first steps. Regul Toxicol Pharmacol 2008; 50:400-11. [DOI: 10.1016/j.yrtph.2008.01.011] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Accepted: 01/15/2008] [Indexed: 11/18/2022]
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Filser JG, Hutzler C, Rampf F, Kessler W, Faller TH, Leibold E, Pütz C, Halbach S, Csanády GA. Concentrations of the Propylene Metabolite Propylene Oxide in Blood of Propylene-Exposed Rats and Humans—a Basis for Risk Assessment. Toxicol Sci 2008; 102:219-31. [DOI: 10.1093/toxsci/kfm311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Greim H. Toxicological comments to the discussion about REACH (H. Greim, M. Arand, H. Autrup, H.M. Bolt, J. Bridges, E. Dybing, R. Glomot, V. Foa, R. Schulte-Hermann, Arch Toxicol 2006, 80: 121–124). Reply to the letter to the editor: the need for a new toxicity testing and risk analysis paradigm to implement REACH or any other large scale testing initiative, by B.J. Blaauboer and M.E. Andersen (Arch Toxicol 2007, 81: 385–387). Arch Toxicol 2007; 81:895-6. [PMID: 17558497 DOI: 10.1007/s00204-007-0216-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Accepted: 05/08/2007] [Indexed: 10/23/2022]
Affiliation(s)
- Helmut Greim
- Institute of Toxicology and Environmental Hygiene, Technical University of Munich, Hohenbachernstr. 15-17, 85350 Freising-Weihenstephan, Germany.
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