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Workplace environmental exposure level guide: n-Methyl-2-pyrrolidone. Toxicol Ind Health 2022; 38:309-329. [PMID: 35658636 DOI: 10.1177/07482337221093838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
n-Methyl-2-pyrrolidone (NMP) is a widely used solvent with a mild amine-like odor that can exist in a vapor or aerosol at moderate temperatures. In humans, NMP was reported to induce weak and transient eye irritation and headache. NMP was not a dermal sensitizer and has a low acute toxicity via oral, dermal, and inhalation routes. NMP was not genotoxic/mutagenic in a battery of in vitro and in vivo studies. Furthermore, NMP was not carcinogenic in rats although species-specific liver tumors were identified in mice. Chronic studies in the rat provided a NOAEL of 10 ppm (40 mg/m3) causing only minor effects in males (slightly reduced mean body weight) at 100 ppm (400 mg/m3). Developmental toxicity was considered the critical endpoint (decreased fetal body weights at non-maternally toxic doses). Benchmark dose and PBPK models were utilized to derive an internal dose of 350-470 mg·h/L as a NOAEL for this response and a human equivalent air concentration of 350-490 ppm. With the application of adjustment factors, an 8-h time-weighted average WEEL value of 15 ppm (60 mg/m3) was derived and is expected to provide a significant margin of safety against any potential adverse health effects in workers. To address the potential for respiratory irritation, a short-term exposure level of 30 ppm (120 mg/m3) was derived, and a skin notation is assigned because of the contribution of dermal absorption to the systemic toxicity of NMP.
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Grant KA, Nakayama Wong L, Meng Q, Lee H, Phelps D, Davis S, Salinas M, Luan T, Zhou X. Informed substitution of hazardous chemicals through the lens of California's Safer Consumer Products Alternatives Analysis: Best practices, challenges, and opportunities. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2022; 18:1007-1019. [PMID: 34590786 DOI: 10.1002/ieam.4527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
California adopted the Safer Consumer Products (SCP) regulations in 2013, which mandate that companies that manufacture specific products containing designated chemicals of concern complete an Alternatives Analysis. Alternatives Analysis is a process to avoid regrettable substitution by identifying, comparing, and selecting safer alternatives based on technical functions, hazards, exposure pathways, life-cycle multimedia impacts, and economic impacts. The SCP Alternatives Analysis builds upon and expands existing frameworks for alternatives assessments (AAs). The aim of this study was to identify practices from AA that facilitate the robust assessment of alternatives and that align with SCP requirements and identify gaps in the practice. We evaluated completed AAs for methods regarding transparency and careful documentation of information sources, data gaps, uncertainty, criteria, and justification for decision-making. The AAs in this review demonstrate some of the challenges in the field. Most AAs have a constrained scope and only consider chemical substitutes rather than a broad array of functional alternatives. Their scopes were also limited in the hazard endpoints that were evaluated. This was most noted with ecotoxicity endpoints, which were generally confined to aquatic toxicity. The majority of AAs do not explicitly explain their decision-making methods or adequately discuss tradeoffs across the adverse impacts. The AAs also lack the analysis in the exposure, life-cycle impacts, and economic impacts that are required in the SCP Alternatives Analysis process. Further, we recommend strategies and research opportunities to address these challenges and strengthen the practice of AAs. Integr Environ Assess Manag 2022;18:1007-1019. © 2021 SETAC.
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Affiliation(s)
- Kelly A Grant
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Lynn Nakayama Wong
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Qingyu Meng
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Heather Lee
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Diana Phelps
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Suzanne Davis
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Melissa Salinas
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Tony Luan
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
| | - Xiaoying Zhou
- Safer Consumer Products program, Department of Toxic Substances Control, Sacramento, California, USA
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Dose response effect of chemical surface concentration on percutaneous penetration in human: In vivo + in vitro. Regul Toxicol Pharmacol 2022; 132:105186. [DOI: 10.1016/j.yrtph.2022.105186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 04/27/2022] [Accepted: 05/04/2022] [Indexed: 11/21/2022]
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Azhari L, Zhou X, Sousa B, Yang Z, Gao G, Wang Y. Effects of Extended Aqueous Processing on Structure, Chemistry, and Performance of Polycrystalline LiNi xMn yCo zO 2 Cathode Powders. ACS APPLIED MATERIALS & INTERFACES 2020; 12:57963-57974. [PMID: 33332088 DOI: 10.1021/acsami.0c20105] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The prospect of aqueous processing of LiNixMnyCozO2 (NMC) cathodes has significant appeal to battery manufacturers for the reduction in materials cost, toxicological risk, and environmental impact compared to conventional N-methyl-2-pyrrolidone (NMP)-based processing. However, the effects of aqueous processing of NMC powders at industrial timescales are not well studied, with prior studies mostly focusing on relatively brief water washing processes. In this work, we investigate the bulk and surface impacts of extended aqueous processing of polycrystalline NMC powders with different compositions. We demonstrate that at timescales of several hours, polycrystalline NMC is susceptible to intergranular fracture, with the severity of fracture scaling with the NMC nickel content. While bulk crystallinity and composition are unchanged, surface sensitive techniques such as X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) indicate that the exposure of water leads to a level of delithiation, nickel reduction, and reconstruction from the layered to rock-salt structure at the surface of individual grains. Dynamic single NMC microparticle compression testing suggests that the resulting mechanical stresses weaken the integrity of the polycrystalline particle and increases susceptibility of intergranular fracture. The initially degraded surfaces along with the increased surface area lead to faster capacity fade and impedance growth during electrochemical cycling. From this work, it is demonstrated that NMC powders require surface or grain boundary modifications to make industrial-scale aqueous cathode processing viable, especially for next-generation nickel-rich NMC chemistries.
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Affiliation(s)
- Luqman Azhari
- Department of Materials Science and Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
| | - Xiangyu Zhou
- Department of Materials Science and Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
| | - Bryer Sousa
- Department of Materials Science and Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
| | - Zhenzhen Yang
- Chemical Science and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Guanhui Gao
- Rice Electron Microscopy Center, Rice University, 6100 Main Street, Houston, Texas 77005, United States
| | - Yan Wang
- Department of Materials Science and Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
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Hettinga J, Carlisle R. Vaccination into the Dermal Compartment: Techniques, Challenges, and Prospects. Vaccines (Basel) 2020; 8:E534. [PMID: 32947966 PMCID: PMC7564253 DOI: 10.3390/vaccines8030534] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 01/06/2023] Open
Abstract
In 2019, an 'influenza pandemic' and 'vaccine hesitancy' were listed as two of the top 10 challenges to global health by the WHO. The skin is a unique vaccination site, due to its immune-rich milieu, which is evolutionarily primed to respond to challenge, and its ability to induce both humoral and cellular immunity. Vaccination into this dermal compartment offers a way of addressing both of the challenges presented by the WHO, as well as opening up avenues for novel vaccine formulation and dose-sparing strategies to enter the clinic. This review will provide an overview of the diverse range of vaccination techniques available to target the dermal compartment, as well as their current state, challenges, and prospects, and touch upon the formulations that have been developed to maximally benefit from these new techniques. These include needle and syringe techniques, microneedles, DNA tattooing, jet and ballistic delivery, and skin permeabilization techniques, including thermal ablation, chemical enhancers, ablation, electroporation, iontophoresis, and sonophoresis.
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Affiliation(s)
| | - Robert Carlisle
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford OX3 7DQ, UK;
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Koslitz S, Meier S, Schindler BK, Weiß T, Koch HM, Brüning T, Käfferlein HU. Biomonitoring of N-ethyl-2-pyrrolidone in automobile varnishers. Toxicol Lett 2014; 231:142-6. [DOI: 10.1016/j.toxlet.2014.10.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 10/07/2014] [Accepted: 10/09/2014] [Indexed: 10/24/2022]
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Influence of water dilution on percutaneous absorption of N-vinyl-2-pyrrolidone in vivo and ex vivo in rats and ex vivo in humans. Arch Toxicol 2014; 89:2007-14. [DOI: 10.1007/s00204-014-1342-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 08/14/2014] [Indexed: 11/25/2022]
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Meier S, Schindler BK, Koslitz S, Koch HM, Weiss T, Käfferlein HU, Brüning T. Biomonitoring of exposure to N-methyl-2-pyrrolidone in workers of the automobile industry. ACTA ACUST UNITED AC 2013; 57:766-73. [PMID: 23337464 DOI: 10.1093/annhyg/mes111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
N-methyl-2-pyrrolidone (NMP) is an important organic solvent for varnishes in industry. NMP has been previously shown to be a developmental toxicant in rodents. This study reports current exposures to NMP in the spraying department of an automobile plant using biological monitoring. Two specific metabolites, 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methyl-succinimide (2-HMSI), were analyzed in 69 urine samples of 14 workers exposed to NMP and 9 nonexposed controls. Three different working tasks ('loading' and 'cleaning' of the sprayer system and 'wiping/packing' of the sprayed materials) and three sampling times (preshift, postshift, and preshift of the following day) were studied in exposed workers. Median exposures of 5-HNMP and 2-HMSI in postshift urine of exposed workers were 0.91 and 0.52mg g(-1) creatinine, respectively, whereas median levels in controls were below the limit of detection. Decreased levels of 5-HNMP were observed in preshift urine samples on the following day (0.39mg g(-1) creatinine) in exposed workers, while the concentration of 2-HMSI did not change (0.49mg g(-1) creatinine). Highest exposures occurred during sprayer cleaning with a maximum level of 8.31mg g(-1) creatinine of 5-HNMP in postshift urine. In contrast to 'wipers/packers', no decrease in 5-HNMP could be observed in preshift urine samples on day 2 of the 'loaders' and 'cleaners'. Overall, exposure in terms of 5-HNMP postshift and 2-HMSI preshift of the following day were well below the current biological limit values of the European Union (70 and 20mg g(-1) creatinine). Our results provide initial data on NMP exposure in the automobile industry and suggest that the analysis of 5-HNMP in preshift samples also provides essential information, particularly in situations involving direct handling of liquid NMP-containing formulations.
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Affiliation(s)
- Swetlana Meier
- Institut für Prävention und Arbeitsmedizin der Deutschen Gesetzlichen Unfallversicherung, Institut der Ruhr Universität Bochum (IPA), Bürkle-de-la-Camp Platz 1, 44789 Bochum, Germany
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Korinth G, Wellner T, Schaller KH, Drexler H. Potential of the octanol–water partition coefficient (logP) to predict the dermal penetration behaviour of amphiphilic compounds in aqueous solutions. Toxicol Lett 2012; 215:49-53. [DOI: 10.1016/j.toxlet.2012.09.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 08/14/2012] [Accepted: 09/18/2012] [Indexed: 11/16/2022]
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Schindler BK, Koslitz S, Meier S, Belov VN, Koch HM, Weiss T, Brüning T, Käfferlein HU. Quantification of Four Major Metabolites of Embryotoxic N-Methyl- and N-Ethyl-2-pyrrolidone in Human Urine by Cooled-Injection Gas Chromatography and Isotope Dilution Mass Spectrometry. Anal Chem 2012; 84:3787-94. [DOI: 10.1021/ac300439w] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Birgit K. Schindler
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Stephan Koslitz
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Swetlana Meier
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Vladimir N. Belov
- Max Planck Institute for Biophysical Chemistry, Facility for Synthetic Chemistry,
Am Fassberg 11, 37077 Göttingen, Germany
| | - Holger M. Koch
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Tobias Weiss
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Thomas Brüning
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
| | - Heiko U. Käfferlein
- Institute for Prevention and
Occupational Medicine of the German Social Accident Insurance, Ruhr-University Bochum (IPA), Bürkle-de-la-Camp
Platz 1, 44789 Bochum, Germany
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Sitarek K, Stetkiewicz J, Wąsowicz W. Evaluation of Reproductive Disorders in Female Rats Exposed to N-Methyl-2-Pyrrolidone. ACTA ACUST UNITED AC 2012; 95:195-201. [DOI: 10.1002/bdrb.21001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Accepted: 11/02/2011] [Indexed: 11/07/2022]
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Determination of N-methyl-2-pyrrolidone and its metabolites in urine by micellar electrokinetic chromatography. OPEN CHEM 2011. [DOI: 10.2478/s11532-011-0062-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractA fast and accurate micellar electrokinetic capillary chromatography (MEKC) method was developed for monitoring N-methyl-2-pyrrolidone (NMP) exposure. Baseline separation of NMP and its main metabolites: 5-hydroxy-N-methyl-2-pyrrolidone (5HNMP), N-methylsuccinimide (MSI), 2-hydroxy-N-methylsuccinimide (2HMSI), and 2-pyrrolidone (2P) was obtained within 6 min in an uncoated fused silica capillary using 5 mM phosphate buffer and 140 mM sodium dodecyl sulfate (pH 7.1) as background electrolyte (BGE). On-line UV-detection was performed at 200 nm and the applied electric field was 400 V cm−1. Possible interference of BGE-induced system peaks on separation was investigated by computer simulation and no such interference was observed. The developed MEKC method combined with solid phase extraction for sample preparation was successfully applied to the analysis of urine of rats exposed to NMP. The urinary excretion was determined in 0–6 h and 6–24 h specimens collected after an intragastic administration of 308 mg NMP / kg rat body weight. The results of NMP disposition kinetics in rat urine are reported for NMP and metabolites.
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13
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Nishimura S, Yasui H, Miyauchi H, Kikuchi Y, Kondo N, Takebayashi T, Tanaka S, Mikoshiba Y, Omae K, Nomiyama T. A cross-sectional observation of effect of exposure to N-methyl-2-pyrrolidone (NMP) on workers' health. INDUSTRIAL HEALTH 2009; 47:355-362. [PMID: 19672008 DOI: 10.2486/indhealth.47.355] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This study was aimed at clarifying the effect of exposure to N-methyl-2-pyrrolidone (NMP) on workers' health. Fifteen male NMP-exposed workers and 15 referent male workers were recruited for this study. Exposure concentrations were assessed by determining NMP in the breathing zones and urinary NMP. Clinical examinations, motor and sensory nerve conduction velocities in the dominant arm, and neurobehavioral tests were carried out. The subjects were asked to complete self-administered questionnaires for subjective symptoms and psychological assessment. The mean NMP exposure concentrations ranged from 0.14 to 0.26 ppm, and urinary NMP levels at the end of each workday ranged from 0.17 to 0.22 mg/l, throughout the work week. In terms of clinical data, motor and sensory nerve conduction velocities, neurobehavioral tests, and subjective symptom assessments, there were no differences and no dose-dependent changes in either the means or the prevalence of abnormal findings between NMP-exposed and referent workers.
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Affiliation(s)
- Shigeru Nishimura
- Department of Preventive Medicine and Public Health, Shinshu University School of Medicine, Nagano 390-8621, Japan
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14
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Bader M, Wrbitzky R, Blaszkewicz M, Schäper M, van Thriel C. Human volunteer study on the inhalational and dermal absorption of N-methyl-2-pyrrolidone (NMP) from the vapour phase. Arch Toxicol 2007; 82:13-20. [PMID: 17721780 DOI: 10.1007/s00204-007-0230-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Accepted: 07/27/2007] [Indexed: 10/22/2022]
Abstract
N-Methyl-2-pyrrolidone (NMP) is a versatile organic solvent frequently used for surface cleaning such as paint stripping or graffiti removal. Liquid NMP is rapidly absorbed through the skin but dermal vapour phase absorption might also play an important role for the uptake of the solvent. This particular aspect was investigated in an experimental study with 16 volunteers exposed to 80 mg/m(3) NMP for 8 h under either whole-body, i.e. inhalational plus dermal, or dermal-only conditions. Additionally, the influence of moderate physical workload on the uptake of NMP was studied. The urinary concentrations of NMP and its metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) were followed for 48 h and analysed by gas chromatography-mass spectrometry (GC-MS). Percutaneous uptake delayed the elimination peak times and the apparent biological half-lives of NMP and 5-HNMP. Under resting conditions, dermal-only exposure resulted in the elimination of 71 +/- 8 mg NMP equivalents as compared to 169 +/- 15 mg for whole-body exposure. Moderate workload yielded 79 +/- 8 mg NMP (dermal-only) and 238 +/- 18 mg (whole-body). Thus, dermal absorption from the vapour phase may contribute significantly to the total uptake of NMP, e.g. from workplace atmospheres. As the concentration of airborne NMP does not reflect the body dose, biomonitoring should be carried out for surveillance purposes.
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Affiliation(s)
- Michael Bader
- Department of Occupational Medicine, Hannover Medical School, OE 5370, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
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Saillenfait AM, Sabaté JP, Gallissot F. Comparative developmental toxicities of the three major metabolites ofN-methyl-2-pyrrolidone after oral administration in rats. J Appl Toxicol 2007; 27:571-81. [PMID: 17370238 DOI: 10.1002/jat.1238] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The developmental toxicity of the three main metabolites of N-methyl-2-pyrrolidone (NMP) was studied in Sprague-Dawley rats. Pregnant rats were given 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP; 0, 250, 500, 750 or 1000 mg kg(-1) day(-1)), N-methylsuccinimide (MSI; 0, 500, 750, 1000 or 1250 mg kg(-1) day(-1)), or 2-hydroxyN-methylsuccinimide (2-HMSI; 0, 250, 500, 1000 or 1500 mg kg(-1) day(-1)), by gavage, on gestational days (GD) 6-20. No evidence of maternal toxicity was observed in dams given 5-HNMP. Administration of 2-HMSI resulted in overt maternal toxicity at 500 mg kg(-1) day(-1) and higher doses, as indicated by a significant reduction in weight gain and food consumption at the beginning of treatment. There was no evidence of embryo/fetal toxicity in any of the groups treated with 5-HNMP or 2-HMSI. MSI produced marked developmental toxicity in the presence of maternal effects. Maternal body weight gain and food consumption were affected at 750 mg kg(-1) day(-1) MSI, and above. A significant increase in post-implantation loss occurred at 1250 mg kg(-1) day(-1) MSI, and the incidence of fetuses with external or with visceral malformations was significantly increased at 1000 and 1250 mg kg(-1) day(-1) MSI. Malformations mainly consisted of anasarca, cardiovascular defects and diaphragmatic hernia. Fetal weight was significantly reduced at 1000 and 1250 mg kg(-1) day(-1). The incidence of skeletal variations (predominantly cervical ribs, and delayed ossification of skull bones and sternebrae) was significantly elevated at 750 mg kg(-1) day(-1) and higher doses. However, MSI was much less potent than the parent compound. These results indicate that the embryotoxic and teratogenic effects of NMP are not attributable to these metabolites.
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Affiliation(s)
- A M Saillenfait
- Institut National de Recherche et de Sécurité, Avenue de Bourgogne, BP 27, 54501 Vandoeuvre, France.
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