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McNally K, Sams C, Loizou G. Development, testing, parameterisation, and calibration of a human PBK model for the plasticiser, di (2-ethylhexyl) adipate (DEHA) using in silico, in vitro and human biomonitoring data. Front Pharmacol 2023; 14:1165770. [PMID: 37033641 PMCID: PMC10076754 DOI: 10.3389/fphar.2023.1165770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/15/2023] [Indexed: 04/11/2023] Open
Abstract
Introduction: A physiologically based biokinetic model for di (2-ethylhexyl) adipate (DEHA) based on a refined model for di-(2-propylheptyl) phthalate (DPHP) was developed to interpret the metabolism and biokinetics of DEHA following a single oral dosage of 50 mg to two male and two female volunteers. Methods: The model was parameterized using in vitro and in silico methods such as, measured intrinsic hepatic clearance scaled from in vitro to in vivo and algorithmically predicted parameters such as plasma unbound fraction and tissue:blood partition coefficients (PCs). Calibration of the DEHA model was achieved using concentrations of specific downstream metabolites of DEHA excreted in urine. The total fractions of ingested DEHA eliminated as specific metabolites were estimated and were sufficient for interpreting the human biomonitoring data. Results: The specific metabolites of DEHA, mono-2-ethyl-5-hydroxyhexyl adipate (5OH-MEHA), mono-2-ethyl-5-oxohexyl adipate (5oxo-MEHA), mono-5-carboxy-2-ethylpentyl adipate (5cx-MEPA) only accounted for ∼0.45% of the ingested DEHA. Importantly, the measurements of adipic acid, a non-specific metabolite of DEHA, proved to be important in model calibration. Discussion: The very prominent trends in the urinary excretion of the metabolites, 5cx-MEPA and 5OH-MEHA allowed the important absorption mechanisms of DEHA to be modelled. The model should be useful for the study of exposure to DEHA of the general human population.
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Behairy A, Abd El-Rahman GI, Aly SSH, Fahmy EM, Abd-Elhakim YM. Di(2-ethylhexyl) adipate plasticizer triggers hepatic, brain, and cardiac injury in rats: Mitigating effect of Peganum harmala oil. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111620. [PMID: 33396140 DOI: 10.1016/j.ecoenv.2020.111620] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/31/2020] [Accepted: 11/04/2020] [Indexed: 06/12/2023]
Abstract
Di(2-ethylhexyl) adipate (DEHA) is a widely used plasticizer and prevalent environmental contaminant. In this study, DEHA concentrations in the milk, cheese, and butter samples wrapped with food-grade commercial polyethylene films and stored at 4 °C for 30 days were detected using gas chromatographic analysis. Also, the effects of exposure to a high dose of DEHA for a long duration on the liver, brain, and heart of Wistar rats were assessed. Besides, the possible beneficial effect of Peganum harmala oil (PGO), in relieving DEHA induced adverse effects was explored. For this purpose, four groups (8 rats/group) were orally given physiological saline, PGO (320 mg/kg bwt), DEHA (2000 mg/kg bwt), or PGO + DEHA for 60 days. The results revealed that the DEHA concentrations in the tested dairy products were ordered as follows: (butter > cheese > milk). Notably, the detected levels in butter were higher than the specific migration limit in foods. DEHA induced a significant increase in the serum levels of glucose, alanine transaminase, aspartate transaminase, acetylcholine esterase, creatine kinase-myocardium bound, malondialdehyde, tumor necrosis factor-α, and interleukin-1β. But, significant hypoproteinemia, hypoalbuminemia, hypoglobulinemia, and hypocholesterolemia were evident following DEHA exposure. A significant reduction in the serum level of superoxide dismutase, reduced glutathione, and brain-derived neurotrophic factor was recorded. Besides, a significant downregulation in hepatic CYP2E1, brain glial fibrillary acidic protein, and cardiac troponin I gene expression was noticed. Moreover, DEHA exposure induced a significant decrease in Bcl-2 immunolabeling, but Caspase-3 immunoexpression was increased. On the contrary, PGO significantly recused DEHA injurious impacts. Therefore, PGO could represent a promising agent for preventing DEHA-induced hepatotoxicity, neurotoxicity, and cardiotoxicity.
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Affiliation(s)
- Amany Behairy
- Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Ghada I Abd El-Rahman
- Department of Clinical Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Sanaa S H Aly
- Department of Food Engineering and Packaging Research, Food Technology Research Institute, Agriculture Research Center, Giza, Egypt
| | - Esraa M Fahmy
- Department of Pharmacology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Yasmina M Abd-Elhakim
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt.
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Fuchsmann P, Tena Stern M, Münger LH, Pimentel G, Burton KJ, Vionnet N, Vergères G. Nutrivolatilomics of Urinary and Plasma Samples to Identify Candidate Biomarkers after Cheese, Milk, and Soy-Based Drink Intake in Healthy Humans. J Proteome Res 2020; 19:4019-4033. [DOI: 10.1021/acs.jproteome.0c00324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
| | | | | | | | | | - Nathalie Vionnet
- Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Guy Vergères
- Agroscope, Schwarzenburgstrasse 161, 3003 Bern, Switzerland
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Mochalski P, Unterkofler K. Quantification of selected volatile organic compounds in human urine by gas chromatography selective reagent ionization time of flight mass spectrometry (GC-SRI-TOF-MS) coupled with head-space solid-phase microextraction (HS-SPME). Analyst 2016; 141:4796-803. [DOI: 10.1039/c6an00825a] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Selective reagent ionization time of flight mass spectrometry with NO+as the reagent ion in conjunction with gas chromatography and head-space solid-phase microextraction was used to determine 16 volatiles in human urine.
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Affiliation(s)
- Paweł Mochalski
- Breath Research Institute of the University of Innsbruck
- A-6850 Dornbirn
- Austria
| | - Karl Unterkofler
- Breath Research Institute of the University of Innsbruck
- A-6850 Dornbirn
- Austria
- Vorarlberg University of Applied Sciences
- A-6850 Dornbirn
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6
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Bernard L, Décaudin B, Lecoeur M, Richard D, Bourdeaux D, Cueff R, Sautou V. Analytical methods for the determination of DEHP plasticizer alternatives present in medical devices: a review. Talanta 2014; 129:39-54. [PMID: 25127563 DOI: 10.1016/j.talanta.2014.04.069] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 04/21/2014] [Accepted: 04/23/2014] [Indexed: 01/13/2023]
Abstract
Until 2010, diethylhexylphthalate (DEHP) was the plasticizer most commonly used to soften PVC medical devices (MDs), because of a good efficiency/cost ratio. In flexible plasticized PVC, phthalates are not chemically bound to PVC and they are released into the environment and thus may come into contact with patients. The European Directive 2007/47/CE, classified DEHP as a product with a toxicity risk and restricted its use in MDs. MD manufacturers were therefore forced to quickly find alternatives to DEHP to maintain the elasticity of PVC nutrition tubings, infusion sets and hemodialysis lines. Several replacement plasticizers, so-called "alternative to DEHP plasticizers" were incorporated into the MDs. Nowadays, the risk of exposure to these compounds for hospitalized patients, particularly in situations classified "at risk", has not yet been evaluated, because migrations studies, providing sufficient exposure and human toxicity data have not been performed. To assess the risk to patients of DEHP plasticizer alternatives, reliable analytical methods must be first developed in order to generate data that supports clinical studies being conducted in this area. After a brief introduction of the characteristics and toxicity of the selected plasticizers used currently in MDs, this review outlines recently analytical methods available to determine and quantify these plasticizers in several matrices, allowing the evaluation of potential risk and so risk management.
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Affiliation(s)
- L Bernard
- CHU Clermont-Ferrand, Pôle Pharmacie, Rue Montalembert, 63003 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, EA 4676 C-BIOSENSS, BP 10448, F-63000 Clermont-Ferrand, France.
| | - B Décaudin
- Université Lille Nord de France, EA4481, GRIIOT, BP83, 59006 Lille, France; CHRU Lille, Pharmacie, Avenue Oscar Lambret, 59037 Lille, France
| | - M Lecoeur
- Université Lille Nord de France, EA4481, GRIIOT, BP83, 59006 Lille, France
| | - D Richard
- CHU Clermont-Ferrand, Service de Pharmacologie (CREPTA), Rue Montalembert, 63003 Clermont-Ferrand, France
| | - D Bourdeaux
- CHU Clermont-Ferrand, Pôle Pharmacie, Rue Montalembert, 63003 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, EA 4676 C-BIOSENSS, BP 10448, F-63000 Clermont-Ferrand, France
| | - R Cueff
- Clermont Université, Université d'Auvergne, EA 4676 C-BIOSENSS, BP 10448, F-63000 Clermont-Ferrand, France
| | - V Sautou
- CHU Clermont-Ferrand, Pôle Pharmacie, Rue Montalembert, 63003 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, EA 4676 C-BIOSENSS, BP 10448, F-63000 Clermont-Ferrand, France
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Silva MJ, Samandar E, Ye X, Calafat AM. In vitro metabolites of di-2-ethylhexyl adipate (DEHA) as biomarkers of exposure in human biomonitoring applications. Chem Res Toxicol 2013; 26:1498-502. [PMID: 24016063 DOI: 10.1021/tx400215z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Di-2-ethylhexyl adipate (DEHA) is a common plasticizer used in food packaging. At high doses, DEHA can cause adverse health effects in rats. Although the potential for human exposure to DEHA is high, no DEHA specific biomarkers are identified for human biomonitoring. Using human liver microsomes, we investigated the in vitro phase I metabolism of DEHA and its hydrolytic metabolite mono-2-ethylhexyl adipate (MEHA) and, for comparison purposes, of the analogous di-2-ethylhexyl phthalate (DEHP) and its hydrolytic metabolite mono-2-ethylhexyl phthalate. We unequivocally identified MEHA, a DEHA specific biomarker, and adipic acid, a nonspecific biomarker, using authentic standards. On the basis of their mass spectrometric fragmentation patterns, we tentatively identified two other DEHA specific metabolites: mono-2-ethylhydroxyhexyl adipate (MEHHA) and mono-2-ethyloxohexyl adipate (MEOHA), analogous to the oxidative metabolites of DEHP. Interestingly, although adipic acid was the major in vitro metabolite of DEHA, the analogous phthalic acid was not the major in vitro metabolite of DEHP. Our preliminary data for 144 adults with no known exposure to DEHA suggests that adipic acid is also the main in vivo urinary metabolite, while MEHA, MEHHA, and MEOHA are only minor metabolites. Therefore, the use of these specific metabolites for assessing the exposure of DEHA may be limited to highly exposed populations.
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Affiliation(s)
- Manori J Silva
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention , Atlanta, Georgia 30341, United States
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8
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Fromme H, Gruber L, Schuster R, Schlummer M, Kiranoglu M, Bolte G, Völkel W. Phthalate and di-(2-ethylhexyl) adipate (DEHA) intake by German infants based on the results of a duplicate diet study and biomonitoring data (INES 2). Food Chem Toxicol 2013; 53:272-80. [DOI: 10.1016/j.fct.2012.12.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 12/25/2022]
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Flavouring Group Evaluation 04 −2-Ethylhexyl derivatives from chemical group 2 - Scientific Opinion of the Panel on Food Additives, Flavourings, Processing Aids and Materials in contact with Food (AFC). EFSA J 2009. [DOI: 10.2903/j.efsa.2009.929] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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10
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Fromme H, Gruber L, Schlummer M, Wolz G, Böhmer S, Angerer J, Mayer R, Liebl B, Bolte G. Intake of phthalates and di(2-ethylhexyl)adipate: results of the Integrated Exposure Assessment Survey based on duplicate diet samples and biomonitoring data. ENVIRONMENT INTERNATIONAL 2007; 33:1012-20. [PMID: 17610953 DOI: 10.1016/j.envint.2007.05.006] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Revised: 05/23/2007] [Accepted: 05/23/2007] [Indexed: 05/16/2023]
Abstract
Phthalates are ubiquitous environmental chemicals with potential detrimental health effects. The purpose of our study was to quantify dietary intake of phthalates and of DEHA (Di-ethylhexyl adipate) using duplicate diet samples and to compare these data with the calculated data based on urinary levels of primary and secondary phthalate metabolites. 27 female and 23 male healthy subjects aged 14-60 years collected daily duplicate diet samples over 7 consecutive days. Overall, 11 phthalates were measured in the duplicates by GC/MS and LC/MS methods. Urinary levels of primary and secondary phthalate metabolites are also available. The median (95th percentile) daily intake via food was 2.4 (4.0) microg/kg b.w. (Di-2-ethylhexyl phthalate, DEHP), 0.3 (1.4) microg/kg b.w. (Di-n-butyl phthalate, DnBP), 0.6 (2.1) microg/kg b.w. (Di-isobutyl phthalate, DiBP) and 0.7 (2.2) microg/kg b.w. for DEHA. MEPH (Mono-2-ethylhexyl phthalate) was detectable only in minor concentrations in the samples, thus conversion of DEHP to MEHP and dietary intake of MEHP were negligible. When comparing back-calculated intake data of the DEHP metabolites with dietary DEHP intake from the day before significant correlations were observed for most of the metabolites. No correlation was found for DnBP and only a weak but significant correlation for DiBP. The median and 95th percentile daily dietary intake of all target analytes did not exceed the recommended tolerable daily intake. Our data indicated that food was the predominant intake source of DEHP, whilst other sources considerably contributed to the daily intake of DnBP and DiBP in an adult population.
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Affiliation(s)
- Hermann Fromme
- Department of Environmental Health, Bavarian Health and Food Safety Authority, Veterinärstrasse 2, D-85764 Oberschleissheim, Germany.
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11
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Stingel D, Feldmeier P, Richling E, Kempf M, Elss S, Labib S, Schreier P. Urinary 2-ethyl-3-oxohexanoic acid as major metabolite of orally administered 2-ethylhexanoic acid in human. Mol Nutr Food Res 2007; 51:301-6. [PMID: 17309117 DOI: 10.1002/mnfr.200600136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Human metabolism of 2-ethylhexanoic acid (2-EHA), which is a known metabolite of important phthalates, was investigated using 2-EHA-contaminated food. The results of our studies reveal that the major catabolic pathway of 2-EHA in human is beta-oxidation. The dominant final urinary metabolite was identified and quantified as 3-oxo-2-ethylhexanoic acid (3-oxo-2-EHA), but only after immediate methylation of the extract from urine and prior to GC-MS analysis. Former studies without the precaution of immediate methylation had found 4-heptanone as the major metabolite, which is obviously an artifact arising from the decarboxylation of 3-oxo-2-EHA.
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Affiliation(s)
- Dana Stingel
- Lehrstuhl für Lebensmittelchemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
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12
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Opinion of the Scientific Panel on food additives, flavourings, processing aids and materials in contact with food (AFC) related to epoxidised soybean oil used in food contact materials. EFSA J 2006. [DOI: 10.2903/j.efsa.2006.332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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13
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Soria AC, Martínez-Castro I, Sanz J. Analysis of volatile composition of honey by solid phase microextraction and gas chromatography-mass spectrometry. J Sep Sci 2003. [DOI: 10.1002/jssc.200301368] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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14
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Kroes R, Müller D, Lambe J, Löwik MRH, van Klaveren J, Kleiner J, Massey R, Mayer S, Urieta I, Verger P, Visconti A. Assessment of intake from the diet. Food Chem Toxicol 2002; 40:327-85. [PMID: 11893401 DOI: 10.1016/s0278-6915(01)00113-2] [Citation(s) in RCA: 249] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Exposure assessment is one of the key parts of the risk assessment process. Only intake of toxicologically significant amounts can lead to adverse health effects even for a relatively toxic substance. In the case of chemicals in foods this is based on three major aspects: (i) how to determine quantitatively the presence of a chemical in individual foods and diets, including its fate during the processes within the food production chain; (ii) how to determine the consumption patterns of the individual foods containing the relevant chemicals; (iii) how to integrate both the likelihood of consumers eating large amounts of the given foods and of the relevant chemical being present in these foods at high levels. The techniques used for the evaluation of these three aspects have been critically reviewed in this paper to determine those areas where the current approaches provide a solid basis for assessments and those areas where improvements are needed or desirable. For those latter areas, options for improvements are being suggested, including, for example, the development of a pan-European food composition database, activities to understand better effects of processing on individual food chemicals, harmonisation of food consumption survey methods with the option of a regular pan-European survey, evaluation of probabilistic models and the development of models to assess exposure to food allergens. In all three areas, the limitations of the approaches currently used lead to uncertainties which can either cause an over- or underestimation of real intakes and thus risks. Given these imprecisions, risk assessors tend to build in additional uncertainty factors to avoid health-relevant underestimates. This is partly done by using screening methods designed to look for "worst case" situations. Such worse case assumptions lead to intake estimates that are higher than reality. These screening methods are used to screen all those chemicals with a safe intake distribution. For chemicals with a potential risk, more information is needed to allow more refined screening or even the most accurate estimation. More information and more refined methods however, require more resources. The ultimate aims are: (1) to obtain appropriate estimations for the presence and quantity of a given chemical in a food and in the diet in general; (2) to assess the consumption patterns for the foods containing these substances, including especially those parts of the population with high consumption and thus potentially high intakes; and (3) to develop and apply tools to predict reliably the likelihood of high end consumption with the presence of high levels of the relevant substances. It has thus been demonstrated that a tiered approach at all three steps can be helpful to optimise the use of the available resources: if relatively crude tools - designed to provide a "worst case" estimate - do not suggest a toxicologically significant exposure (or a relevant deficit of a particular nutrient) it may not be necessary to use more sophisticated tools. These will be needed if initially high intakes are indicated for at least parts of the population. Existing pragmatic approaches are a first crude step to model food chemical intake. It is recommended to extend, refine and validate this approach in the near future. This has to result in a cost-effective exposure assessment system to be used for existing and potential categories of chemicals. This system of knowledge (with information on sensitivities, accuracy, etc.) will guide future data collection.
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Affiliation(s)
- R Kroes
- Utrecht University, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Yalelaan 2, PO Box 80176, NL-3508 TD, Utrecht, The Netherlands
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Mills GA, Walker V. Headspace solid-phase microextraction profiling of volatile compounds in urine: application to metabolic investigations. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 753:259-68. [PMID: 11334339 DOI: 10.1016/s0378-4347(00)00554-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Volatile compounds contribute substantially to the metabolic pool in man. Their analysis in body fluids is problematic. We investigated headspace solid-phase microextraction (HS-SPME) with Carboxen-polydimethylsiloxane fibres and gas chromatography-mass spectrometry for profiling urinary volatile components. These fibres were more sensitive for very volatile and sulfur compounds than three other phases tested. We detected a wide range of compounds in normal urine at acid and alkaline pH. Profiles presented for five individuals with metabolic disturbances demonstrate abnormal accumulation of sulfur compounds, fatty acids and plasticisers. HS-SPME can complement profiling of non-volatile compounds in metabolic investigations and could be a useful extension of the diagnostic repertoire.
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Affiliation(s)
- G A Mills
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK
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Walker V, Mills GA. Urine 4-heptanone: a beta-oxidation product of 2-ethylhexanoic acid from plasticisers. Clin Chim Acta 2001; 306:51-61. [PMID: 11282094 DOI: 10.1016/s0009-8981(01)00390-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
4-Heptanone is a common volatile constituent of human urine and is of unknown origin. We hypothesised that it arises from in vivo beta-oxidation of 2-ethylhexanoic acid (EHA) from plasticisers, similar to formation of 3-heptanone from valproic acid. We investigated urine from individuals with normal and increased plasticiser exposure. Using GC/MS, solvent-extracted organic acids were analysed as trimethylsilyl (TMS) derivatives and heptanone with headspace solid-phase microextraction. We identified 3-oxo-2-ethylhexanoic acid, the beta-oxidation product of EHA, as an enol in all samples. This is the first report of its TMS mass spectrum. We also found 2-ethyl-1,6-hexanedioic acid and 5-hydroxyEHA, omega- and omega-1-oxidation products of EHA, respectively, and 2-ethylhexanoylglucuronide, but only in trace amounts in some plasticiser samples. These compounds have not been reported in human urine, nor has the TMS mass spectrum of 5-hydroxyEHA. The median concentrations of 3-oxoethylhexanoic acid and total 4-heptanone of seven plasticiser samples were around 30--175-fold higher than normal samples. 4-Heptanone was barely detectable and 3-oxoethylhexanoic acid was not increased in an eighth plasticiser sample, from a baby with deficiency of 2-methylbranched-chain acyl-CoA dehydrogenase. beta-Oxidation is a major catabolic pathway of EHA in man, and might be involved in the metabolism of other branched-chain drugs and environmental pollutants.
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Affiliation(s)
- V Walker
- Department of Chemical Pathology, Southampton General Hospital, Level D, South Block, Mailpoint 6, Tremona Road, Southampton, SO16 6YD, UK.
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Gilbert J, Rossi L. European priorities for research to support legislation in the area of food contact materials and articles. FOOD ADDITIVES AND CONTAMINANTS 2000; 17:83-127. [PMID: 10793858 DOI: 10.1080/026520300283621] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.
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Affiliation(s)
- J Gilbert
- Ministry of Agriculture, Fisheries and Food, Central Science Laboratory, Sand Hutton, York, UK.
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Wahl HG, Hoffmann A, Häring HU, Liebich HM. Identification of plasticizers in medical products by a combined direct thermodesorption--cooled injection system and gas chromatography--mass spectrometry. J Chromatogr A 1999; 847:1-7. [PMID: 10515691 DOI: 10.1016/s0021-9673(99)00138-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The combination of a new thermodesorption module with a cooled injection system now provides a powerful system for direct analysis of volatile trace compounds in gaseous, liquid and solid samples by gas chromatography-mass spectrometry (GC-MS). As a cooled injection system is used for the cryofocusing of the desorbed volatiles the GC-MC system still can be used for the regular analysis of liquid samples. Although plasticizers usually are analyzed by GC-MS after solvent extraction, contaminated solvents and glassware are very well known problems. Analysis of plasticizers in plastic materials by direct thermodesorption instead saves time and avoids cross contaminations. Many medical products are made of plasticized polyvinyl chloride. Extraction of the common plasticizer di(2-ethylhexyl) phthalate (DEHP) into blood will occur, and harmful effects of DEHP in the human body have been suggested. We therefore analyzed 21 different plastic devices which are used for various invasive techniques in medicine by direct thermodesorption GC-MS. In some of the plastics up to 30 different components were identified. By far the most common plasticizer found was DEHP, followed by diethyl and dibutyl phthalates.
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Affiliation(s)
- H G Wahl
- Medizinische Universitätsklinik Abt. IV, Zentrallabor, Germany
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Lake BG, Price RJ, Cunninghame ME, Walters DG. Comparison of the effects of di-(2-ethylhexyl)adipate on hepatic peroxisome proliferation and cell replication in the rat and mouse. Toxicology 1997; 123:217-26. [PMID: 9355940 DOI: 10.1016/s0300-483x(97)00125-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effects of di-(2-ethylhexyl)adipate (DEHA) have been compared in female F344 rats and female B6C3F1 mice fed diets containing 0-4.0% DEHA and 0-2.5% DEHA, respectively, for periods of 1, 4 and 13 weeks. In both the rat and mouse treatment with DEHA at all time points produced a dose-dependent increase in relative liver weight and hepatic peroxisome proliferation as demonstrated by the induction of peroxisomal (cyanide-insensitive palmitoyl-CoA oxidation) and microsomal (lauric acid 12-hydroxylase) fatty acid oxidising enzyme activities. The magnitude of induction of peroxisome proliferation was similar in both species. Replicative DNA synthesis was studied by implanting osmotic pumps containing 5-bromo-2'-deoxyuridine during study weeks 0-1, 3-4 and 12-13. After 1 week DEHA treatment hepatocyte labelling index values were increased in rats given 2.5 and 4.0% DEHA and mice given 0.6-2.5% DEHA. While DEHA treatment for 4 and 13 weeks did not increase labelling index values in the rat, a sustained stimulation of replicative DNA synthesis was observed in mice given 1.2 and 2.5% DEHA. The results of this study demonstrate a species difference in the hepatic effects of DEHA, in that at some dose levels DEHA can produce a sustained stimulation of replicative DNA synthesis in mouse but not in rat liver. Sustained cell replication provides a better correlation with the observed formation of liver tumours in chronic studies with DEHA in female mice, but not in female rats, than the magnitude of stimulation of hepatic peroxisome proliferation.
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Affiliation(s)
- B G Lake
- BIBRA International, Carshalton, Surrey, UK
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