1
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Api AM, Belsito D, Biserta S, Botelho D, Bruze M, Burton GA, Buschmann J, Cancellieri MA, Dagli ML, Date M, Dekant W, Deodhar C, Fryer AD, Gadhia S, Jones L, Joshi K, Lapczynski A, Lavelle M, Liebler DC, Na M, O'Brien D, Patel A, Penning TM, Ritacco G, Rodriguez-Ropero F, Romine J, Sadekar N, Salvito D, Schultz TW, Siddiqi F, Sipes IG, Sullivan G, Thakkar Y, Tokura Y, Tsang S. RIFM fragrance ingredient safety assessment, p-tolualdehyde, CAS Registry Number 104-87-0. Food Chem Toxicol 2021; 149 Suppl 1:111982. [PMID: 33454360 DOI: 10.1016/j.fct.2021.111982] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 12/01/2020] [Accepted: 01/10/2021] [Indexed: 12/01/2022]
Abstract
The existing information supports the use of this material as described in this safety assessment. p-Tolualdehyde was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity, skin sensitization potential, and environmental safety. Data from read-across analog benzaldehyde (CAS # 100-52-7) show that p-tolualdehyde is not expected to be genotoxic. Data from read-across analog cuminaldehyde (CAS # 122-03-2) provided p-tolualdehyde a No Expected Sensitization Induction Level (NESIL) of 1100 μg/cm2 for the skin sensitization endpoint. The repeated dose toxicity, developmental and reproductive toxicity, and local respiratory toxicity endpoints were completed using the threshold of toxicological concern (TTC) for a Cramer Class I material, and the exposure to p-tolualdehyde is below the TTC (0.03 mg/kg/day, 0.03 mg/kg/day, and 1.4 mg/day, respectively). The phototoxicity/photoallergenicity endpoints were evaluated based on data from read-across analog 4-ethylbenzaldehyde (CAS # 4748-78-1); p-tolualdehyde is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; p-tolualdehyde was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.
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Affiliation(s)
- A M Api
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Belsito
- Columbia University Medical Center, Department of Dermatology, 161 Fort Washington Ave., New York, NY, 10032, USA
| | - S Biserta
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Botelho
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Bruze
- Malmo University Hospital, Department of Occupational & Environmental Dermatology, Sodra Forstadsgatan 101, Entrance 47, Malmo, SE-20502, Sweden
| | - G A Burton
- School of Natural Resources & Environment, University of Michigan, Dana Building G110, 440 Church St, Ann Arbor, MI, 58109, USA
| | - J Buschmann
- Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625, Hannover, Germany
| | - M A Cancellieri
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M L Dagli
- University of Sao Paulo, School of Veterinary Medicine and Animal Science, Department of Pathology, Av. Prof. dr. Orlando Marques de Paiva, 87, Sao Paulo, CEP 05508-900, Brazil
| | - M Date
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - W Dekant
- University of Wuerzburg, Department of Toxicology, Versbacher Str. 9, 97078, Würzburg, Germany
| | - C Deodhar
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A D Fryer
- Oregon Health Science University, 3181 SW Sam Jackson Park Rd, Portland, OR, 97239, USA
| | - S Gadhia
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - L Jones
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - K Joshi
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Lapczynski
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Lavelle
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D C Liebler
- Vanderbilt University School of Medicine, Department of Biochemistry, Center in Molecular Toxicology, 638 Robinson Research Building, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA
| | - M Na
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D O'Brien
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Patel
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T M Penning
- University of Pennsylvania, Perelman School of Medicine, Center of Excellence in Environmental Toxicology, 1316 Biomedical Research Building (BRB) II/III, 421 Curie Boulevard, Philadelphia, PA, 19104-3083, USA
| | - G Ritacco
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - F Rodriguez-Ropero
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - J Romine
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - N Sadekar
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Salvito
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T W Schultz
- The University of Tennessee, College of Veterinary Medicine, Department of Comparative Medicine, 2407 River Dr, Knoxville, TN, 37996- 4500, USA
| | - F Siddiqi
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - I G Sipes
- Department of Pharmacology, University of Arizona, College of Medicine, 1501 North Campbell Avenue, P.O. Box 245050, Tucson, AZ, 85724-5050, USA
| | - G Sullivan
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA.
| | - Y Thakkar
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - Y Tokura
- The Journal of Dermatological Science (JDS), Editor-in-Chief, Professor and Chairman, Department of Dermatology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - S Tsang
- Research Institute for Fragrance Materials, Inc, 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
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RIFM fragrance ingredient safety assessment, 4-ethylbenzaldehyde, CAS Registry Number 4748-78-1. Food Chem Toxicol 2020; 146 Suppl 1:111700. [PMID: 32860860 DOI: 10.1016/j.fct.2020.111700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/05/2020] [Accepted: 08/19/2020] [Indexed: 11/21/2022]
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3
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Api AM, Belsito D, Biserta S, Botelho D, Bruze M, Burton GA, Buschmann J, Cancellieri MA, Dagli ML, Date M, Dekant W, Deodhar C, Fryer AD, Gadhia S, Jones L, Joshi K, Lapczynski A, Lavelle M, Liebler DC, Na M, O'Brien D, Patel A, Penning TM, Ritacco G, Rodriguez-Ropero F, Romine J, Sadekar N, Salvito D, Schultz TW, Siddiqi F, Sipes IG, Sullivan G, Thakkar Y, Tokura Y, Tsang S. RIFM fragrance ingredient safety assessment, cuminic aldehyde, CAS Registry Number 122-03-2. Food Chem Toxicol 2020; 144 Suppl 1:111498. [PMID: 32640342 DOI: 10.1016/j.fct.2020.111498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/02/2020] [Indexed: 10/23/2022]
Affiliation(s)
- A M Api
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Belsito
- Member Expert Panel, Columbia University Medical Center, Department of Dermatology, 161 Fort Washington Ave., New York, NY, 10032, USA
| | - S Biserta
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Botelho
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Bruze
- Member Expert Panel, Malmo University Hospital, Department of Occupational & Environmental Dermatology, Sodra Forstadsgatan 101, Entrance 47, Malmo, SE-20502, Sweden
| | - G A Burton
- Member Expert Panel, School of Natural Resources & Environment, University of Michigan, Dana Building G110, 440 Church St., Ann Arbor, MI, 58109, USA
| | - J Buschmann
- Member Expert Panel, Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625, Hannover, Germany
| | - M A Cancellieri
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M L Dagli
- Member Expert Panel, University of Sao Paulo, School of Veterinary Medicine and Animal Science, Department of Pathology, Av. Prof. dr. Orlando Marques de Paiva, 87, Sao Paulo, CEP 05508-900, Brazil
| | - M Date
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - W Dekant
- Member Expert Panel, University of Wuerzburg, Department of Toxicology, Versbacher Str. 9, 97078, Würzburg, Germany
| | - C Deodhar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A D Fryer
- Member Expert Panel, Oregon Health Science University, 3181 SW Sam Jackson Park Rd., Portland, OR, 97239, USA
| | - S Gadhia
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - L Jones
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - K Joshi
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Lapczynski
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Lavelle
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D C Liebler
- Member Expert Panel, Vanderbilt University School of Medicine, Department of Biochemistry, Center in Molecular Toxicology, 638 Robinson Research Building, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA
| | - M Na
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D O'Brien
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Patel
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T M Penning
- Member of Expert Panel, University of Pennsylvania, Perelman School of Medicine, Center of Excellence in Environmental Toxicology, 1316 Biomedical Research Building (BRB) II/III, 421 Curie Boulevard, Philadelphia, PA, 19104-3083, USA
| | - G Ritacco
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - F Rodriguez-Ropero
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - J Romine
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - N Sadekar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Salvito
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T W Schultz
- Member Expert Panel, The University of Tennessee, College of Veterinary Medicine, Department of Comparative Medicine, 2407 River Dr., Knoxville, TN, 37996- 4500, USA
| | - F Siddiqi
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - I G Sipes
- Member Expert Panel, Department of Pharmacology, University of Arizona, College of Medicine, 1501 North Campbell Avenue, P.O. Box 245050, Tucson, AZ, 85724-5050, USA
| | - G Sullivan
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA.
| | - Y Thakkar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - Y Tokura
- Member Expert Panel, The Journal of Dermatological Science (JDS), Editor-in-Chief, Professor and Chairman, Department of Dermatology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - S Tsang
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
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Spiliotopoulos D, Koelbert C. Assessment of the miniaturized liquid Ames microplate format (MPF™) for a selection of the test items from the recommended list of genotoxic and non-genotoxic chemicals. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2020; 856-857:503218. [PMID: 32928366 DOI: 10.1016/j.mrgentox.2020.503218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 10/24/2022]
Abstract
The Ames microplate format (MPF™) is a miniaturized version of the plate agar Ames tests that takes advantage of a liquid microplate approach in 384-well plates with a color change-based readout. This method, already compared to the Ames test in Petri dishes, is used to assess the genotoxic potential of a variety of test items, including (but not limited to) chemicals, environmental samples, and drug candidates. 61 chemicals were selected from the updated recommended lists of genotoxic and non-genotoxic chemicals for assessment of the performance of new or improved genotoxicity tests and tested in up to five bacterial strains. The agreement with the data from the scientific literature (over 90%) confirms the reliability of the Ames MPF™ as a cost-effective and 3R-compliant alternative to the regulatory Ames test that allows to predict and evaluate chemicals' mutagenicity in a faster, less laborious and, if available, automatable manner.
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5
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Hsieh CJ, Sun M, Osborne G, Ricker K, Tsai FC, Li K, Tomar R, Phuong J, Schmitz R, Sandy MS. Cancer Hazard Identification Integrating Human Variability: The Case of Coumarin. Int J Toxicol 2019; 38:501-552. [PMID: 31845612 DOI: 10.1177/1091581819884544] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Coumarin is a naturally occurring sweet-smelling benzopyrone that may be extracted from plants or synthesized for commercial uses. Its uses include as a flavoring agent, fragrance enhancer, and odor-masking additive. We reviewed and evaluated the scientific evidence on the carcinogenicity of coumarin, integrating information from carcinogenicity studies in animals with mechanistic and other relevant data, including data from toxicogenomic, genotoxicity, and metabolism studies, and studies of human variability of a key enzyme, CYP2A6. Increases in tumors were observed in multiple studies in rats and mice in multiple tissues. Our functional pathway analysis identified several common cancer-related biological processes/pathways affected by coumarin in rat liver following in vivo exposure and in human primary hepatocytes exposed in vitro. When coumarin 7-hydroxylation by CYP2A6 is compromised, this can lead to a shift in metabolism to the 3,4-epoxidation pathway and increased generation of electrophilic metabolites. Mechanistic data align with 3 key characteristics of carcinogens, namely formation of electrophilic metabolites, genotoxicity, and induction of oxidative stress. Considerations of metabolism, human variability in CYP2A6 activity, and coumarin hepatotoxicity in susceptible individuals provide additional support for carcinogenicity concern. Our analysis illustrates the importance of integrating information on human variability in the cancer hazard identification process.
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Affiliation(s)
- ChingYi Jennifer Hsieh
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Meng Sun
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Gwendolyn Osborne
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Karin Ricker
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Feng C Tsai
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Kate Li
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Rajpal Tomar
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA.,Retired
| | - Jimmy Phuong
- Department of Biomedical and Health Informatics, University of Washington, Seattle, WA, USA
| | - Rose Schmitz
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
| | - Martha S Sandy
- Office of Environmental Health Hazard Assessment, CalEPA, Sacramento and Oakland, CA, USA
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6
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Api AM, Belsito D, Biserta S, Botelho D, Bruze M, Burton GA, Buschmann J, Cancellieri MA, Dagli ML, Date M, Dekant W, Deodhar C, Fryer AD, Gadhia S, Jones L, Joshi K, Lapczynski A, Lavelle M, Liebler DC, Na M, O'Brien D, Patel A, Penning TM, Ritacco G, Rodriguez-Ropero F, Romine J, Sadekar N, Salvito D, Schultz TW, Siddiqi F, Sipes IG, Sullivan G, Thakkar Y, Tokura Y, Tsang S. RIFM fragrance ingredient safety assessment, benzaldehyde, CAS Registry Number 100-52-7. Food Chem Toxicol 2019; 134 Suppl 2:110878. [PMID: 31622729 DOI: 10.1016/j.fct.2019.110878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/10/2019] [Accepted: 10/08/2019] [Indexed: 10/25/2022]
Affiliation(s)
- A M Api
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Belsito
- Member Expert Panel, Columbia University Medical Center, Department of Dermatology, 161 Fort Washington Ave., New York, NY, 10032, USA
| | - S Biserta
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Botelho
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Bruze
- Member Expert Panel, Malmo University Hospital, Department of Occupational & Environmental Dermatology, Sodra Forstadsgatan 101, Entrance 47, Malmo, SE-20502, Sweden
| | - G A Burton
- Member Expert Panel, School of Natural Resources & Environment, University of Michigan, Dana Building G110, 440 Church St., Ann Arbor, MI, 58109, USA
| | - J Buschmann
- Member Expert Panel, Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625, Hannover, Germany
| | - M A Cancellieri
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M L Dagli
- Member Expert Panel, University of Sao Paulo, School of Veterinary Medicine and Animal Science, Department of Pathology, Av. Prof. dr. Orlando Marques de Paiva, 87, Sao Paulo, CEP 05508-900, Brazil
| | - M Date
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - W Dekant
- Member Expert Panel, University of Wuerzburg, Department of Toxicology, Versbacher Str. 9, 97078, Würzburg, Germany
| | - C Deodhar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A D Fryer
- Member Expert Panel, Oregon Health Science University, 3181 SW Sam Jackson Park Rd., Portland, OR, 97239, USA
| | - S Gadhia
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - L Jones
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - K Joshi
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Lapczynski
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - M Lavelle
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D C Liebler
- Member Expert Panel, Vanderbilt University School of Medicine, Department of Biochemistry, Center in Molecular Toxicology, 638 Robinson Research Building, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA
| | - M Na
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D O'Brien
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - A Patel
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T M Penning
- Member of Expert Panel, University of Pennsylvania, Perelman School of Medicine, Center of Excellence in Environmental Toxicology, 1316 Biomedical Research Building (BRB) II/III, 421 Curie Boulevard, Philadelphia, PA, 19104-3083, USA
| | - G Ritacco
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - F Rodriguez-Ropero
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - J Romine
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - N Sadekar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - D Salvito
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - T W Schultz
- Member Expert Panel, The University of Tennessee, College of Veterinary Medicine, Department of Comparative Medicine, 2407 River Dr., Knoxville, TN, 37996- 4500, USA
| | - F Siddiqi
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - I G Sipes
- Member Expert Panel, Department of Pharmacology, University of Arizona, College of Medicine, 1501 North Campbell Avenue, P.O. Box 245050, Tucson, AZ, 85724-5050, USA
| | - G Sullivan
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA.
| | - Y Thakkar
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
| | - Y Tokura
- Member Expert Panel, The Journal of Dermatological Science (JDS), Editor-in-Chief, Professor and Chairman, Department of Dermatology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - S Tsang
- Research Institute for Fragrance Materials, Inc., 50 Tice Boulevard, Woodcliff Lake, NJ, 07677, USA
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7
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Abstract
Interlaboratory studies are common in toxicology, particularly for the introduction of alternative assays. Numerous papers are available on the statistical analysis of interlaboratory studies, but these deal primarily with the case of a replicated single sample studied in several laboratories. This approach can be used for some assays, but for the majority, the results will be unsatisfactory, i.e. involving great variability between both the dose groups and the laboratories. However, the primary objective of toxicological assays is to achieve similarity between the sizes of effects, rather than to determine absolute values. In the parametric model, the sizes of effects are the studentised differences from the negative control or, for the commonly used dose-response designs, the similarity of the slopes of the dose-response curves. Standard approaches for the estimation of intralaboratory and interlaboratory variability, including Mandel plots, are introduced, and new approaches are presented for demonstrating similarity of effect sizes, with or without assuming a dose-response model. One approach is based on a modification of the parallel-line assay, the other is based on a modification of the interaction contrasts of the analysis of variance. SAS programs are given for all approaches, and real data from an interlaboratory immunotoxicological study are analysed as a demonstration.
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Affiliation(s)
- Ludwig A Hothorn
- Bioinformatics Unit, University of Hannover, 30419 Hannover, Germany
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8
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Yuan P, Dong J, Zhao W, Zhuo M, Li S, Huang S, Li J. Qualitative and quantitative assessment of genotoxins using SRRzlysis reporter under the control of a newly designed SOS responsive promoter in Escherichia coli. RSC Adv 2019; 9:35662-35670. [PMID: 35528065 PMCID: PMC9074414 DOI: 10.1039/c9ra06202e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/19/2019] [Indexed: 11/22/2022] Open
Abstract
A new bacterial genotoxicity detection strain was constructed, in which the cell lysis gene of SRRz from a lambda phage was controlled by a new designed SOS responsive element, designated as Escherichia coli BL21/pUC-PST. The biosensor responded only after 0.5 h contact with mutagens and the changes in cell culture turbidity could be easily differentiated with the naked eyes from the control sample. This SOS/SRRz system presented a dose-dependent manner to five model DNA-damaging agents with an improved detection sensitivity. The limits of detection (LODs) were 0.026 μM for mitomycin C, 320.4 μM for azinphos-methyl, 34.4 μM for methyl methanesulfonate, 4.6 μM for dithianone and 6.0 μM for dichlofluanid, which were much lower than previously reported. By performing binary and ternary mixture experiments, the toxic equivalency concept was validated in the E. coli SOS/SRRz system by comparison with bioanalytical equivalent concentrations (BEQ) and overall toxic equivalent concentration (TEQmixture) using Cr(vi) as the reference compound. Pearson analysis indicated that a strong correlation existed between the TEQmixture and BEQ values. Thus the TEQmixture could be presented as the Cr(vi) equivalent concentration from its dose–effect lysis profiles for the environmental sample. The proposed genotoxicity reporter strain allows for easier qualitative characterization and quantitative interpretation of the TEQmixture values using Cr(vi) as the reference for environmental water samples. A new bacterial genotoxicity detection strain was constructed, in which the cell lysis gene of SRRz from a lambda phage was controlled by a new designed SOS responsive element, designated as Escherichia coli BL21/pUC-PST.![]()
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Affiliation(s)
- Pengfei Yuan
- School of Biology and Biological Engineering
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Junqing Dong
- School of Biology and Biological Engineering
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Weibin Zhao
- School of Biology and Biological Engineering
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Min Zhuo
- School of Biology and Biological Engineering
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Shuang Li
- School of Biology and Biological Engineering
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Shaobin Huang
- School of Environment and Energy
- South China University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- China
| | - Jianjun Li
- State Key Laboratory of Applied Microbiology Southern China
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application
- Guangdong Institute of Microbiology
- Guangzhou 510070
- China
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9
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Rainer B, Pinter E, Czerny T, Riegel E, Kirchnawy C, Marin-Kuan M, Schilter B, Tacker M. Suitability of the Ames test to characterise genotoxicity of food contact material migrates. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2018; 35:2230-2243. [PMID: 30257137 DOI: 10.1080/19440049.2018.1519259] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Non-intentionally added substances (NIAS) are chemical impurities which can migrate from packaging materials (FCM) into food. Safety assessment of NIAS is required by European law, but currently there is no comprehensive testing strategy available. In this context, one key element is to get insight on the potential presence of genotoxic NIAS in FCM migrates. This raises questions about the limit at which genotoxins can be detected in complex mixtures such as FCM migrates, and if such limits of detection (LOD) would be compatible with safety. In this context, the present review assesses the suitability of the Ames assay to address genotoxicity of FCM migrates. Lowest effective concentrations of packaging-related and other chemicals in test media were retrieved from scientific literature and used as surrogates of LODs to be benchmarked against a value of 0.01 mg kg-1 (10 ppb) in migrates. This is a pragmatic threshold used in FCM safety evaluation to prioritise substances requiring proper identification and risk assessment. The analysis of the data shows that only potent genotoxins can theoretically be detectable at a level of 0.01 mg kg-1 in migrates or food. Only a minority (10%) of genotoxic chemicals reported to be associated with FCMs could be picked up at a level of 0.01 mg kg-1 or lower. Overall, this review shows that the Ames test in its present form cannot be used as standalone method for evaluating the genotoxic potential of FCM migrates, but must be used together with other information from analytical chemistry and FCM manufacturing.
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Affiliation(s)
- Bernhard Rainer
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Elisabeth Pinter
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Thomas Czerny
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Elisabeth Riegel
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Christian Kirchnawy
- b Department for Microbiology and Cell Culture , OFI - Austrian Research Institute for Chemistry and Technology , Vienna , Austria
| | - Maricel Marin-Kuan
- c Chemical Food Safety , Nestlé Research Center , Lausanne , Switzerland
| | - Benoît Schilter
- c Chemical Food Safety , Nestlé Research Center , Lausanne , Switzerland
| | - Manfred Tacker
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
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10
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Umbuzeiro GDA, Heringa M, Zeiger E. In Vitro Genotoxicity Testing: Significance and Use in Environmental Monitoring. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 157:59-80. [PMID: 27631084 DOI: 10.1007/10_2015_5018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
There is ongoing concern about the consequences of mutations in humans and biota arising from environmental exposures to industrial and other chemicals. Genetic toxicity tests have been used to analyze chemicals, foods, drugs, and environmental matrices such as air, water, soil, and wastewaters. This is because the mutagenicity of a substance is highly correlated with its carcinogenicity. However, no less important are the germ cell mutations, because the adverse outcome is related not only to an individual but also to population levels. For environmental analysis the most common choices are in vitro assays, and among them the most widely used is the Ames test (Salmonella/microsome assay). There are several protocols and methodological approaches to be applied when environmental samples are tested and these are discussed in this chapter, along with the meaning and relevance of the obtained responses. Two case studies illustrate the utility of in vitro mutagenicity tests such as the Ames test. It is clear that, although it is not possible to use the outcome of the test directly in risk assessment, the application of the assays provides a great opportunity to monitor the exposure of humans and biota to mutagenic substances for the purpose of reducing or quantifying that exposure.
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Affiliation(s)
| | - Minne Heringa
- National Institute of Public Health and the Environment (RIVM), 1, 3720 BA, Bilthoven, The Netherlands
| | - Errol Zeiger
- Errol Zeiger Consulting, 800 Indian Springs Road, Chapel Hill, NC, 27514, USA
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11
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Peauger L, Azzouz R, Gembus V, Ţînţaş ML, Sopková-de Oliveira Santos J, Bohn P, Papamicaël C, Levacher V. Donepezil-Based Central Acetylcholinesterase Inhibitors by Means of a “Bio-Oxidizable” Prodrug Strategy: Design, Synthesis, and in Vitro Biological Evaluation. J Med Chem 2017; 60:5909-5926. [DOI: 10.1021/acs.jmedchem.7b00702] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ludovic Peauger
- VFP Therapies, 15 rue François
Couperin, 76000 Rouen, France
| | - Rabah Azzouz
- VFP Therapies, 15 rue François
Couperin, 76000 Rouen, France
| | - Vincent Gembus
- VFP Therapies, 15 rue François
Couperin, 76000 Rouen, France
| | - Mihaela-Liliana Ţînţaş
- Normandie
Université, COBRA, UMR 6014 et FR 3038, Univ Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Jana Sopková-de Oliveira Santos
- Centre
d’Etudes et de Recherche sur le Médicament de Normandie, Université de Caen, Boulevard Becquerel, 14032 Caen Cedex, France
| | - Pierre Bohn
- Department
of Nuclear Medicine, Henri Becquerel Cancer Center and Rouen University
Hospital and QuantIF LITIS (Equipe d’Accueil (EA) 4108-Federation
Recherche (FR) National Center for Scientific Research (CNRS) 3638),
Faculty of Medicine, University of Rouen, Rouen 76821, France
| | - Cyril Papamicaël
- Normandie
Université, COBRA, UMR 6014 et FR 3038, Univ Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Vincent Levacher
- Normandie
Université, COBRA, UMR 6014 et FR 3038, Univ Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
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12
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Luijten M, Zwart EP, Dollé MET, de Pooter M, Cox JA, White PA, van Benthem J. Evaluation of the LacZ reporter assay in cryopreserved primary hepatocytes for In vitro genotoxicity testing. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2016; 57:643-655. [PMID: 27859631 DOI: 10.1002/em.22063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Assessment of genotoxic potential is an important step in the safety evaluation of chemical substances. Under most regulatory jurisdictions, the first tier of testing comprises a standard battery of in vitro genotoxicity tests in bacterial and mammalian cells. However, the mammalian cell tests commonly used exhibit a relatively high rate of misleading positive results, which may lead to unnecessary in vivo testing. We previously established a proof-of-concept for the LacZ reporter assay in proliferating primary hepatocytes as a promising alternative genotoxicity test. Here, cryopreserved instead of freshly isolated hepatocytes were used and the assay was evaluated in more detail. We examined the effect of cryopreservation on phenotype and metabolic capacity of the LacZ hepatocytes, and assessed the predictive performance of the assay by testing a set of substances comprising true positive, true negative, and misleading positive substances. Additionally, a historical negative control database was created and the type of mutations induced was analyzed for two of the substances tested. Our findings indicate that proliferating cryopreserved primary hepatocytes derived from LacZ plasmid mice retain their hepatocyte-specific characteristics and metabolic competence. Furthermore, we demonstrate that both gene mutations and genome rearrangements due to large deletions can be detected with the LacZ reporter assay. The assay seems to have a lower rate of misleading positive test results compared to the assays currently used. Together, our findings strongly support the use of the LacZ reporter assay in cryopreserved primary hepatocytes as follow-up to the standard in vitro test battery for genotoxicity testing. Environ. Mol. Mutagen. 57:643-655, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Mirjam Luijten
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Edwin P Zwart
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Martijn E T Dollé
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Maaike de Pooter
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Julie A Cox
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Paul A White
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Jan van Benthem
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
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13
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Pant K, Bruce S, Sly J, Klug Laforce M, Springer S, Cecil M, Andrus E, Dakoulas E, Wagner VO, Hewitt NJ, Kulkarni R. Bacterial mutagenicity assays: Vehicle and positive control results from the standard Ames assay, the 6- and 24-well miniaturized plate incorporation assays and the Ames II™ assay. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2016; 57:483-496. [PMID: 27198925 DOI: 10.1002/em.22014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 03/12/2016] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
Bacterial mutation assays are conducted routinely as part of the safety assessment of new chemicals. The OECD Test Guideline (TG) 471 describes the conduct of the standard agar plate Ames assay, required for regulatory submissions. Higher throughput non-OECD 471 TG assays, such as the miniaturized plate incorporation and Ames II™ assays, can be used for prescreening purposes. We have compiled historical vehicle and positive control data generated using these methods. The historical database is comprised from experiments spanning 9 years and includes >1000 experiments from the standard Ames assay using the plate incorporation and pre-incubation methods (TA98, TA100, TA1535, TA1537, and WP2 uvrA), >50 experiments from the 6-well (TA98, TA100, TA1535, TA97a, and WP2 uvrA) and >100 experiments from the 24-well (TA98, TA100, TA102, TA1535, TA1537, and TA97a) plate incorporation assays, and >1000 experiments from the Ames II™ assay (TA98 and TAMix). Although miniaturization to a 24-well format made the measurement of control revertant colonies in TA1537 and TA1535 more difficult; this can be overcome by using an alternative strain with a higher spontaneous reversion rate (i.e., using TA97a instead of TA1537) or by increasing the number of replicate wells to 12 (for TA1535). All three miniaturized methods, including the Ames II™ assay, were responsive to known mutagens and the responses were reproducible over years of use. These data demonstrate the excellent reproducibility of the standard and miniaturized bacterial mutation assays using positive control chemicals. Environ. Mol. Mutagen. 57:483-496, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | | | - Jamie Sly
- BioReliance by SAFC, Rockville, Maryland
| | | | | | - Mark Cecil
- BioReliance by SAFC, Rockville, Maryland
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14
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Martijn BJ, Van Rompay AR, Penders EJM, Alharbi Y, Baggelaar PK, Kruithof JC, Rietjens IMCM. Development of a 4-NQO toxic equivalency factor (TEF) approach to enable a preliminary risk assessment of unknown genotoxic compounds detected by the Ames II test in UV/H₂O₂ water treatment samples. CHEMOSPHERE 2016; 144:338-345. [PMID: 26378870 DOI: 10.1016/j.chemosphere.2015.08.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/21/2015] [Accepted: 08/23/2015] [Indexed: 06/05/2023]
Abstract
An approach to enable a preliminary risk assessment of unknown genotoxic compounds formed by MP UV/H2O2 treatment of nitrate rich water, is described. Since the identity and concentration of specific genotoxic compounds is not established yet, a compound specific risk assessment cannot be performed. This limitation is circumvented by introducing a toxic equivalency factor, converting the concentration of unknown genotoxic compounds expressed by an Ames II test response into equivalent concentrations of 4-nitroquinoline oxide (4-NQO), to enable a preliminary risk assessment. Based on the obtained 4-NQO equivalent concentrations for the tested water samples and 4-NQO carcinogenicity data, an indication of the associated risk of the by MP UV/H2O2 treatment produced nitrated genotoxic compounds is obtained via the margin of exposure (MOE) approach. Based on a carcinogen study by Tang et al. (2004), a body weight of 70 kg and a drinking water consumption of 2 L per day, the 4-NQO equivalent concentration should not exceed 80 ng/L associated with a negligible risk. Application of this approach on samples from MP UV/H2O2 treated water of a full scale drinking water production facility, a 4-NQO equivalent concentration of 107 ng/L was established. These results indicate a safety concern in case this water would be distributed as drinking water without further post treatment.
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Affiliation(s)
- Bram J Martijn
- Wageningen University, Division of Toxicology, P.O. Box 8000, 6700 EA Wageningen, The Netherlands; Wetsus European Centre of Excellence for Sustainable Water Technology, P.O. Box 1113; 8900 CC Leeuwarden, The Netherlands; PWN Water Supply Company North Holland, P.O. Box 2113, 1990 AC Velserbroek, The Netherlands.
| | - An R Van Rompay
- VITO - Environmental Risk & Health - Team ABS, Industriezone Vlasmeer 7, 2400 Mol, Belgium
| | - Eric J M Penders
- Het Waterlaboratorium, P.O Box 734, 2300 RS Haarlem, The Netherlands
| | - Yousif Alharbi
- Wageningen University, Division of Toxicology, P.O. Box 8000, 6700 EA Wageningen, The Netherlands
| | | | - Joop C Kruithof
- Wetsus European Centre of Excellence for Sustainable Water Technology, P.O. Box 1113; 8900 CC Leeuwarden, The Netherlands
| | - Ivonne M C M Rietjens
- Wageningen University, Division of Toxicology, P.O. Box 8000, 6700 EA Wageningen, The Netherlands
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15
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Dambach DM, Misner D, Brock M, Fullerton A, Proctor W, Maher J, Lee D, Ford K, Diaz D. Safety Lead Optimization and Candidate Identification: Integrating New Technologies into Decision-Making. Chem Res Toxicol 2015; 29:452-72. [DOI: 10.1021/acs.chemrestox.5b00396] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Donna M. Dambach
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Dinah Misner
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Mathew Brock
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Aaron Fullerton
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - William Proctor
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Jonathan Maher
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Dong Lee
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Kevin Ford
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
| | - Dolores Diaz
- Department of Safety Assessment, Genentech, Inc., 1 DNA
Way, South San Francisco, California 94080, United States
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16
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Amberg A, Harvey JS, Czich A, Spirkl HP, Robinson S, White A, Elder DP. Do Carboxylic/Sulfonic Acid Halides Really Present a Mutagenic and Carcinogenic Risk as Impurities in Final Drug Products? Org Process Res Dev 2015. [DOI: 10.1021/acs.oprd.5b00106] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander Amberg
- Sanofi-Aventis Deutschland GmbH, R&D DSAR/Preclinical Safety FF, Industriepark Hoechst, Building H831, D-65926 Frankfurt, Germany
| | - James S. Harvey
- GlaxoSmithKline Pre-Clinical Development, Park Road, Ware, Hertfordshire SG12 0DP, U.K
| | - Andreas Czich
- Sanofi-Aventis Deutschland GmbH, R&D DSAR/Preclinical Safety FF, Industriepark Hoechst, Building H831, D-65926 Frankfurt, Germany
| | - Hans-Peter Spirkl
- Sanofi-Aventis Deutschland GmbH, R&D DSAR/Preclinical Safety FF, Industriepark Hoechst, Building H831, D-65926 Frankfurt, Germany
| | - Sharon Robinson
- GlaxoSmithKline Pre-Clinical Development, Park Road, Ware, Hertfordshire SG12 0DP, U.K
| | - Angela White
- GlaxoSmithKline Pre-Clinical Development, Park Road, Ware, Hertfordshire SG12 0DP, U.K
| | - David P. Elder
- GlaxoSmithKline Pre-Clinical Development, Park Road, Ware, Hertfordshire SG12 0DP, U.K
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17
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Escobar P, Kemper R, Tarca J, Nicolette J, Kenyon M, Glowienke S, Sawant S, Christensen J, Johnson T, McKnight C, Ward G, Galloway S, Custer L, Gocke E, O’Donovan M, Braun K, Snyder R, Mahadevan B. Bacterial mutagenicity screening in the pharmaceutical industry. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2013; 752:99-118. [DOI: 10.1016/j.mrrev.2012.12.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 12/06/2012] [Accepted: 12/10/2012] [Indexed: 12/13/2022]
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18
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Abstract
Bacterial mutagenicity tests, specifically the Salmonella and E. coli reverse mutation (Ames) test, are widely used and are usually required before a chemical, drug, pesticide, or food additive can be registered for use. The tests are also widely used for environmental monitoring to detect mutagens in air or water. Their use is based on the showing that a positive result in the test was highly predictive for carcinogenesis. This chapter describes the Salmonella and E. coli tests, presents protocols for their use, and addresses data interpretation and reporting.
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19
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Ulker Z, Alpsoy L, Mihmanli A. Assessment of cytotoxic and apoptotic effects of benzaldehyde using different assays. Hum Exp Toxicol 2012; 32:858-64. [DOI: 10.1177/0960327112470271] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Benzaldehyde (BA) occurs naturally in a number of plants, including cherry, fig and peach fruit and carnation flowers at therapeutic doses. In addition, it is used in cosmetics, personal care products and food as a preservative. In this study, we aimed to determine the cytotoxic and apoptotic effects of different concentrations of BA on cultured human lymphocytes using lactate dehydrogenase assay, cell proliferation (water-soluble tetrazolium salts-1) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) test (apoptotic test) as a group of cytotoxicity tests at 6th and 24th h on human lymphocyte cell culture. The cytotoxicity increased when cells were treated with 10, 25 and 50 μg/mL concentrations of BA ( p < 0.05). Moreover, treatment of the cells with the same concentrations significantly decreased the cell number at the 6th and 24th hours ( p < 0.05). TUNEL assay results also show that the concentration of BA at 10, 25 and 50 μg/mL caused DNA damage significantly ( p < 0.05). According to our results, the toxic and genotoxic effects of BA have to be further evaluated before using in cosmetic and food products.
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Affiliation(s)
- Z. Ulker
- Fatih University, Science and Art Faculty, Biology Department, Istanbul, Turkey
| | - L. Alpsoy
- Fatih University, Science and Art Faculty, Biology Department, Istanbul, Turkey
| | - A. Mihmanli
- Bezmialem University, Faculty of Dentistry, Istanbul, Turkey
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20
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Scientific Opinion on Flavouring Group Evaluation 20, Revision 4 (FGE.20Rev4): Benzyl alcohols, benzaldehydes, a related acetal, benzoic acids, and related esters from chemical groups 23 and 30. EFSA J 2012. [DOI: 10.2903/j.efsa.2012.2994] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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21
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Caldwell JC. DEHP: Genotoxicity and potential carcinogenic mechanisms—A review. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2012; 751:82-157. [DOI: 10.1016/j.mrrev.2012.03.001] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/22/2012] [Accepted: 03/22/2012] [Indexed: 10/28/2022]
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22
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Smith KEC, Heringa MB, Uytewaal M, Mayer P. The dosing determines mutagenicity of hydrophobic compounds in the Ames II assay with metabolic transformation: passive dosing versus solvent spiking. Mutat Res 2012; 750:12-8. [PMID: 22989744 DOI: 10.1016/j.mrgentox.2012.07.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 06/15/2012] [Accepted: 07/25/2012] [Indexed: 11/20/2022]
Abstract
The Ames II bacterial mutagenicity assay is a new version of the standard Ames test for screening chemicals for genotoxic activity. However, the use of plastic micro-titer plates has drawbacks in the case of testing hydrophobic mutagens, since sorptive and other losses make it difficult to control and define the exposure concentrations, and they reduce availability for bacterial uptake or to the S9 enzymes. With passive dosing, a biocompatible polymer such as silicone is loaded with the test compound and acts as a partitioning source. It compensates for any losses and results in stable freely dissolved concentrations. Passive dosing using silicone O-rings was applied in the Ames II assay to measure PAH mutagenicity in strains TA98 and TAMix - a mixture of six different bacterial strains detecting six different base-pair substitutions - after metabolic activation by S9. Initially, 10 PAHs were tested with passive dosing from saturated O-rings, aiming at levels in the test medium close to aqueous solubility. Fluoranthene, pyrene and benzo(a)pyrene were mutagenic in both TA98 and TAMix, whereas benz(a)anthracene was mutagenic in TA98 only. The concentration-dependent mutagenic activity of benzo(a)pyrene was then compared for passive dosing and solvent spiking. With spiking, nominal concentrations greatly exceeded aqueous solubility before mutagenicity was observed, due to sorptive losses and limiting dissolution kinetics. In contrast, the passive dosing concentration-response curves were more reproducible, and shifted towards lower concentrations by several orders of magnitude. This study raises fundamental questions about how to introduce hydrophobic test substances in the Ames II assay with biotransformation, since the measured mutagenicity not only depends on the compound potency but also on its supply, sorption and consumption during the assay.
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Affiliation(s)
- Kilian E C Smith
- Department of Environmental Science, Aarhus University, Roskilde, Denmark.
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23
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Bischoff F, Berthelot D, De Cleyn M, Macdonald G, Minne G, Oehlrich D, Pieters S, Surkyn M, Trabanco AA, Tresadern G, Van Brandt S, Velter I, Zaja M, Borghys H, Masungi C, Mercken M, Gijsen HJM. Design and Synthesis of a Novel Series of Bicyclic Heterocycles As Potent γ-Secretase Modulators. J Med Chem 2012; 55:9089-106. [DOI: 10.1021/jm201710f] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Francois Bischoff
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Didier Berthelot
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Michel De Cleyn
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Gregor Macdonald
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Garrett Minne
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Daniel Oehlrich
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Serge Pieters
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Michel Surkyn
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Andrés A. Trabanco
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Gary Tresadern
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Sven Van Brandt
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Ingrid Velter
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Mirko Zaja
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Herman Borghys
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Chantal Masungi
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Marc Mercken
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
| | - Harrie J. M. Gijsen
- Janssen Research & Development, Pharmaceutical Companies of Johnson & Johnson, Beerse, Belgium
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24
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Scientific Opinion on Flavouring Group Evaluation 20, Revision 3(FGE.20Rev3): Benzyl alcohols, benzaldehydes, a related acetal, benzoic acids, and related esters from chemical groups 23 and 30. EFSA J 2011. [DOI: 10.2903/j.efsa.2011.2176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Kirkland D, Reeve L, Gatehouse D, Vanparys P. A core in vitro genotoxicity battery comprising the Ames test plus the in vitro micronucleus test is sufficient to detect rodent carcinogens and in vivo genotoxins. Mutat Res 2011; 721:27-73. [PMID: 21238603 DOI: 10.1016/j.mrgentox.2010.12.015] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 11/12/2010] [Accepted: 12/15/2010] [Indexed: 01/27/2023]
Abstract
In vitro genotoxicity testing needs to include tests in both bacterial and mammalian cells, and be able to detect gene mutations, chromosomal damage and aneuploidy. This may be achieved by a combination of the Ames test (detects gene mutations) and the in vitro micronucleus test (MNvit), since the latter detects both chromosomal aberrations and aneuploidy. In this paper we therefore present an analysis of an existing database of rodent carcinogens and a new database of in vivo genotoxins in terms of the in vitro genotoxicity tests needed to detect their in vivo activity. Published in vitro data from at least one test system (most were from the Ames test) were available for 557 carcinogens and 405 in vivo genotoxins. Because there are fewer publications on the MNvit than for other mammalian cell tests, and because the concordance between the MNvit and the in vitro chromosomal aberration (CAvit) test is so high for clastogenic activity, positive results in the CAvit test were taken as indicative of a positive result in the MNvit where there were no, or only inadequate data for the latter. Also, because Hprt and Tk loci both detect gene-mutation activity, a positive Hprt test was taken as indicative of a mouse-lymphoma Tk assay (MLA)-positive, where there were no data for the latter. Almost all of the 962 rodent carcinogens and in vivo genotoxins were detected by an in vitro battery comprising Ames+MNvit. An additional 11 carcinogens and six in vivo genotoxins would apparently be detected by the MLA, but many of these had not been tested in the MNvit or CAvit tests. Only four chemicals emerge as potentially being more readily detected in MLA than in Ames+MNvit--benzyl acetate, toluene, morphine and thiabendazole--and none of these are convincing cases to argue for the inclusion of the MLA in addition to Ames+MNvit. Thus, there is no convincing evidence that any genotoxic rodent carcinogens or in vivo genotoxins would remain undetected in an in vitro test battery consisting of Ames+MNvit.
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Affiliation(s)
- David Kirkland
- Kirkland Consulting, PO Box 79, Tadcaster LS24 0AS, United Kingdom.
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Heringa MB, Harmsen DJH, Beerendonk EF, Reus AA, Krul CAM, Metz DH, Ijpelaar GF. Formation and removal of genotoxic activity during UV/H(2)O(2)-GAC treatment of drinking water. WATER RESEARCH 2011; 45:366-374. [PMID: 20828782 DOI: 10.1016/j.watres.2010.08.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 08/06/2010] [Accepted: 08/07/2010] [Indexed: 05/29/2023]
Abstract
The objective of this study was to determine the genotoxic activity of water after UV/H(2)O(2) oxidation and GAC filtration. Pre-treated surface water from three locations was treated with UV/H(2)O(2) with medium pressure (MP) lamps and passed through granulated activated carbon (GAC). Samples taken before and after each treatment step were extracted and concentrated by solid phase extraction (SPE) and analyzed for genotoxicity using the Comet assay with HepG2 cells and the Ames II assay. The Comet assay showed no genotoxic response in any of the samples. In the Ames II, no genotoxic response was obtained with the TAMix (a mix of six strains), but the TA98 strain showed an increase in genotoxic activity after MP-UV/H(2)O(2) for all three locations. GAC post treatment effectively reduced the activities to control levels at two of the three locations and to below the level of the pre-treated water at one site. The results indicate that UV/H(2)O(2) treatment may lead to the formation of genotoxic by-products, which can be removed by subsequent GAC filtration.
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Affiliation(s)
- M B Heringa
- KWR Watercycle research institute, PO Box 1072, 3430 BB Nieuwegein, The Netherlands.
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Scientific Opinion on Flavouring Group Evaluation 20, Revision 2 (FGE.20Rev2): Benzyl alcohols, benzaldehydes, a related acetal, benzoic acids, and related esters from chemical groups 23 and 30. EFSA J 2010. [DOI: 10.2903/j.efsa.2010.1405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Umbuzeiro GDA, Rech CM, Correia S, Bergamasco AM, Cardenette GHL, Flückiger-Isler S, Kamber M. Comparison of the Salmonella/microsome microsuspension assay with the new microplate fluctuation protocol for testing the mutagenicity of environmental samples. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2010; 51:31-38. [PMID: 19484728 DOI: 10.1002/em.20504] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The objective of this study was to compare the responses of the Salmonella/microsome microsuspension assay with the new microplate fluctuation protocol (MPF) for the evaluation of the mutagenic activity of environmental samples. Organic extracts of total particulate atmospheric air samples, surface waters, and effluents were tested in dose-response experiments. The assays were performed with strain TA98 in the absence and presence of S9 mix. Both protocols produced similar results, despite the fact that the maximum score of the MPF is limited to 48 wells, whereas in the regular plate assay it is possible to count up to 1,500 colonies using an automatic counter. Similar sensitivities based on the lowest dose that resulted in a positive response were obtained for both assays. The MPF procedure is less laborious (e.g., all-liquid format, use of multichannel pipettors) and allows for automation of the pipetting and dispensing steps, thus, reducing time of the analysis which is particularly important in environmental quality monitoring programs or in effect-directed analysis. The results show that the MPF procedure is a promising tool to test environmental samples for mutagenic activity.
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Affiliation(s)
- Gisela de Aragão Umbuzeiro
- CETESB-Cia de Tecnologia de Saneamento Ambiental, Av. Prof. Frederico, Hermann Jr., 345, São Paulo, Brazil.
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Kamber M, Fluckiger-Isler S, Engelhardt G, Jaeckh R, Zeiger E. Comparison of the Ames II and traditional Ames test responses with respect to mutagenicity, strain specificities, need for metabolism and correlation with rodent carcinogenicity. Mutagenesis 2009; 24:359-66. [DOI: 10.1093/mutage/gep017] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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30
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Flavouring Group Evaluation 54, Revision 1 (FGE.54Rev1): Consideration of benzyl derivatives evaluated by JECFA (57th meeting) structurally related to benzyl alcohols, benzaldehydes, a related acetal, benzoic acids and related esters evaluated by EFSA in. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.1025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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31
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Oakes DJ, Ritchie HE, Woodman PDC, Narup E, Moscova M, Picker K, Webster WS. Genotoxicity studies of a desealant solvent mixture, SR-51. Toxicol Ind Health 2009; 25:5-13. [PMID: 19318500 DOI: 10.1177/0748233709103037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Royal Australian Air Force (RAAF) has reported that personnel involved in F-111 fuel tank maintenance were concerned that exposure to a range of chemicals during the period 1977 to mid-1990s was the cause of health problems, including cancer. Particular concern was directed at SR-51, a desealant chemical mixture containing the following four solvents: aromatic 150 solvent (Aro150), dimethylacetamide, thiophenol (TP), and triethylphosphate. The present study examined the mutagenic potential of SR-51 using a range of well-known mutagen and genotoxin assays. The tests used were i) a modified version of the Ames test, ii) the mouse lymphoma assay, iii) the comet assay (a single-cell gel electrophoresis assay), and iv) a mouse micronucleus test. The modified Ames test used mixed bacterial strains in liquid suspension media. The Ames test results showed that SR-51 (tested up to the cytotoxic concentration of 36 microg/ml, 30 min incubation) in the presence and absence of S9 metabolic activation was not mutagenic. The mouse lymphoma assay used cultured mouse lymphoma cells in a microwell suspension method. The mouse lymphoma assay was also negative with SR-51 (tested up to the cytotoxic concentration of 22.5 microg/ml, 3 h incubation) in the presence and absence of S9 metabolic activation. The Comet assay, using cultured mouse lymphoma cells, showed no evidence of DNA damage in cells exposed up to the cytotoxic concentration of SR-51 at 11.25 microg/ml. The in-vivo mouse micronucleus test was undertaken in wild-type C57Bl6J male mice dosed orally with SR-51for 14 days with a single daily dose up to 360 mg/kg/day (the maximum-tolerated dose). No increases were observed in micronuclei (MN) frequency in bone marrow collected (24 h after final dose) from SR-51-treated mice compared to the number of MN observed in bone marrow collected from untreated mice. Tissues collected from treated mice at necropsy demonstrated a significant increase in spleen weights in the high dose mice. Gas chromatography analysis of SR-51 identified more than 40 individual components and an oxidation product, diphenyldisulfide derived from TP under conditions of mild heating. In conclusion, there was no evidence that SR-51 is mutagenic.
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Affiliation(s)
- D J Oakes
- Discipline of Biomedical Science (Lidcombe Campus), Faculty of Medicine, University of Sydney, 75 East Street, Lidcombe. NSW 2141, Australia.
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Flavouring Group Evaluation 20, Revision 1 (FGE.20Rev1): Benzyl alcohols, benzaldehydes, a related acetal, benzoic acids and related esters from chemical group 23. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Lipscomb JC, El-Demerdash E, Ahmed AE. Haloacetonitriles: metabolism and toxicity. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 198:169-200. [PMID: 19253036 DOI: 10.1007/978-0-387-09647-6_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The haloacetonitriles (HANs) exist in drinking water exclusively as byproducts of disinfection. HANs are found in drinking water more often, and in higher concentrations, when surface water is treated by chloramination. Human exposure occurs through consumption of finished drinking water; oral and dermal contact also occurs, and results from showering, swimming and other activities. HANs are reactive and are toxic to gastrointestinal tissues following oral administration. Such toxicity is characterized by GSH depletion, increased lipid peroxidation, and covalent binding of HAN-associated radioactivity to gut tissues. The presence of GSH in cells is an important protective mechanism against HAN toxicity; depletion of cellular GSH results in increased toxicity. Some studies have demonstrated an apparently synergistic effect between ROS and HAN administration, that may help explain effects observed in GI tissues. ROS are produced in gut tissues, and in vitro evidence indicates that ROS may contribute to the degradation and formation of reactive intermediates from HANs. The rationale for ROS involvement may involve HAN-induced depletion of GSH and the role of GSH in scavenging ROS. In addition to effects on GI tissues, studies show that HAN-derived radiolabel is found covalently bound to proteins and DNA in several organs and tissues. The addition of antioxidants to biologic systems protects against HAN-induced DNA damage. The protection offered by antioxidants supports the role of oxidative stress and the potential for a threshold in han-induced toxicity. However, additional data are needed to substantiate evidence for such a threshold. HANs are readily absorbed from the GI tract and are extensively metabolized. Elimination occurs primarily in urine, as unconjugated one-carbon metabolites. Evidence supports the involvement of mixed function oxidases, the cytochrome P450 enzyme family and GST, in HAN metabolism. Metabolism represents either a detoxification or bioactivation process, depending on the particular HAN and the enzyme involved. HANs can inhibit CYP2E1-mediated metabolism, an effect which may be dependent on a covalent interaction with the enzyme. In addition, HAN compounds inhibit GST-mediated conjugation, but this effect is reversible upon dialysis, indicating that the interaction does not represent covalent binding. No subchronic studies of HAN toxicity are available in the literature. However, studies show that HANs produce developmental toxicity in experimental animals. The nature of developmental toxicity is affected by the type of administration vehicle, which renders interpretation of results more difficult. Skin tumors have been found following dermal application of HANs, but oral studies for carcinogenicity are negative. Pulmonary adenomas were increased following oral administration of HANs, but the A/J strain of mice employed has a characteristically high background rate of such tumors. HANs interact with DNA to produce unscheduled DNA repair, SCE and reverse mutations in Salmonella. HANs did not induce micronuclei or cause alterations in sperm head morphology in mice, but did induce micronuclei in newts. Thus, there is concern for the potential carcinogenicity of HANs. It would be valuable to delineate any relationship between the apparent threshold for micronuclei formation in newts and the potential mechanism of toxicity involving HAN-induced oxidative stress. Dose-response studies in rodents may provide useful information on toxicity mechanisms and dose selection for longer term toxicity studies. Additional studies are warranted before drawing firm conclusions on the hazards of HAN exposure. Moreover, additional studies on HAN-DNA and HAN-protein interaction mechanisms, are needed. Such studies can better characterize the role of metabolism in toxicity of individual HANs, and delineate the role of oxidative stress, both of which enhance the capacity to predict risk. Most needed, now, are new subchronic (and chronic) toxicity studies; the results of such well-planned, controlled, conducted, interpreted and published investigations would be valuable in establishing margins of safety for HANs in human health risk assessment.
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Affiliation(s)
- John C Lipscomb
- Environmental Protection Agency, National Center for Environmental Assessment, Cincinnati, Ohio 45268, USA
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Flavouring Group Evaluation 54 (FGE.54) ‐ Consideration of benzyl derivatives evaluated by JECFA (57th meeting) structurally related to benzyl alcohols, benzaldehydes, a related acetal, benzoic acids and related esters evaluated by EFSA in FGE.20 (2005) ‐ Scientific Opinion of the Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food. EFSA J 2008. [DOI: 10.2903/j.efsa.2008.835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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35
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Flavouring Group Evaluation 52 (FGE.52): Consideration of hydroxy‐ and alkoxy‐substituted benzyl derivatives evaluated by JECFA (57th meeting) structurally related to benzyl alcohols, benzaldehydes, a related acetal, benzoic acids, and related esters evaluated by EFSA in FGE.20 (2005) (Commission Regulation (EC) No 1565/2000 of 18 July 2000) ‐ Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in contact with Food (AFC). EFSA J 2008. [DOI: 10.2903/j.efsa.2008.637] [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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36
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Umbuzeiro GDA, Warren SH, Claxton LD. The mutation spectra of chlorinated drinking water samples using the base-specific TA7000 strains of Salmonella in the microsuspension assay. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2006; 609:26-33. [PMID: 16880003 DOI: 10.1016/j.mrgentox.2006.06.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 03/29/2006] [Accepted: 06/07/2006] [Indexed: 11/21/2022]
Abstract
Mutation spectra analysis can provide important information about the types of genotoxic compounds that can be present in environmental samples. In this study, we used the TA7000 base-specific Salmonella typhimurium tester strains to characterize water samples from two drinking water treatment plants (DWTPs) in São Paulo, Brazil. Because of the small sample sizes of these environmental samples, the use of the microsuspension protocol was necessary. Acidic extracts of drinking water samples from the two DWTPs gave similar responses in the TA7000 strains and caused primarily CG to AT transversions. It is likely that halogenated disinfection by-products, generated during the chlorination of water, are causing the response seen with the TA7000 strains.
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Affiliation(s)
- Gisela de Aragão Umbuzeiro
- CETESB, Cia de Tecnologia de Saneamento Ambiental, Av. Prof. Frederico Hermann Jr, 345, 05459-900 São Paulo, Brazil
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37
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Opinion of the Scientific Panel on food additives, flavourings, processing aids and materials in contact with food (AFC) on a request from the Commission related to Flavouring Group Evaluation 20 (FGE.20): Benzyl alcohols, benzaldehydes, a related acetal,. EFSA J 2006. [DOI: 10.2903/j.efsa.2006.296] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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38
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Sasseville VG, Lane JH, Kadambi VJ, Bouchard P, Lee FW, Balani SK, Miwa GT, Smith PF, Alden CL. Testing paradigm for prediction of development-limiting barriers and human drug toxicity. Chem Biol Interact 2004; 150:9-25. [PMID: 15522258 DOI: 10.1016/j.cbi.2004.06.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2004] [Accepted: 06/29/2004] [Indexed: 11/17/2022]
Abstract
The financial investment grows exponentially as a new chemical entity advances through each stage of discovery and development. The opportunity exists for the modern toxicologist to significantly impact expenditures by the early prediction of potential toxicity/side effect barriers to development by aggressive evaluation of development-limiting liabilities early in drug discovery. Improved efficiency in pharmaceutical research and development lies both in leveraging "best in class" technology and integration with pharmacologic activities during hit-to-lead and early lead optimization stages. To meet this challenge, a discovery assay by stage (DABS) paradigm should be adopted. The DABS clearly delineates to discovery project teams the timing and type of assay required for advancement of compounds to each subsequent level of discovery and development. An integrative core pathology function unifying Drug Safety Evaluation, Molecular Technologies and Clinical Research groups that effectively spans all phases of drug discovery and development is encouraged to drive the DABS. The ultimate goal of such improved efficiency being the accurate prediction of toxicity and side effects that would occur in development before commitment of the large prerequisite resource. Good justification of this approach is that every reduction of development attrition by 10% results in an estimated increase in net present value by $100 million.
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Affiliation(s)
- V G Sasseville
- Drug Safety and Disposition, Millennium Pharmaceuticals, Inc., 45 Sidney Street, Cambridge, MA 02139, USA.
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Flückiger-Isler S, Baumeister M, Braun K, Gervais V, Hasler-Nguyen N, Reimann R, Van Gompel J, Wunderlich HG, Engelhardt G. Assessment of the performance of the Ames II™ assay: a collaborative study with 19 coded compounds. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2004; 558:181-97. [PMID: 15036131 DOI: 10.1016/j.mrgentox.2003.12.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Revised: 12/01/2003] [Accepted: 12/05/2003] [Indexed: 10/26/2022]
Abstract
Nineteen coded chemicals were tested in an international collaborative study for their mutagenic activity. The assay system employed was the Ames II Mutagenicity Assay, using the tester strains TA98 and TAMix (TA7001-7006). The test compounds were selected from a published study with a large data set from the standard Ames plate-incorporation test. The following test compounds including matched pairs were investigated: cyclophoshamide, 2-naphthylamine, benzo(a)pyrene, pyrene, 2-acetylaminofluorene, 4,4'-methylene-bis(2-chloroaniline), 9,10-dimethylanthracene, anthracene, 4-nitroquinoline-N-oxide, diphenylnitrosamine, urethane, isopropyl-N(3-chlorophenyl)carbamate, benzidine, 3,3'-5,5'-tetramethylbenzidine, azoxybenzene, 3-aminotriazole, diethylstilbestrol, sucrose and methionine. The results of both assay systems were compared, and the inter-laboratory consistency of the Ames II test was assessed. Of the eight mutagens selected, six were correctly identified with the Ames II assay by all laboratories, one compound was judged positive by five of six investigators and one by four of six laboratories. All seven non-mutagenic samples were consistently negative in the Ames II assay. Of the four chemicals that gave inconsistent results in the traditional Ames test, three were uniformly classified as either positive or negative in the present study, whereas one compound gave equivocal results. A comparison of the test outcome of the different investigators resulted in an inter-laboratory consistency of 89.5%. Owing to the high concordance between the two test systems, and the low inter-laboratory variability in the Ames II assay results, the Ames II is an effective screening alternative to the standard Ames test, requiring less test material and labor.
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Hothorn LA. Selected biostatistical aspects of the validation of in vitro toxicological assays. Altern Lab Anim 2002; 30 Suppl 2:93-8. [PMID: 12513657 DOI: 10.1177/026119290203002s14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An overview is presented on selected biostatistical aspects of the validation of in vitro toxicological assays. Primarily, the statistical analysis of single assays is discussed. Several approaches are compared for the possible non-monotonic dose-response relationship with a priori unknown shapes. The use of confidence intervals instead of p values for toxicologically appropriate decision making is explained. New methods are discussed for demonstrating interlaboratory similarity for dose-response designs are discussed. For validation, the inappropriateness of the concordance coefficient is shown, and sensitive and specificity as well as predictive values are proposed as alternatives. The problem of the missing gold standard is highlighted.
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Affiliation(s)
- Ludwig A Hothorn
- Department of Bioinformatics, University of Hannover, 30419 Hannover, Germany
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Claxton LD, Houk VS, Warren S. Methods for the spiral Salmonella mutagenicity assay including specialized applications. Mutat Res 2001; 488:241-57. [PMID: 11397652 DOI: 10.1016/s1383-5742(01)00060-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
An automated approach to bacterial mutagenicity testing - the spiral Salmonella assay - was developed to simplify testing and to reduce the labor and materials required to generate dose-responsive mutagenicity information. This document provides the reader with an overview of the spiral assay and a discussion of its application for examining the mutagenic potential of pure compounds, complex environmental mixtures, and interactive effects. Guidelines for performing a routine spiral assay are presented, and alternative test methods intended to overcome a variety of technical difficulties (such as restricted sample availability, sample viscosity or volatility, etc.) are recommended. Methods for the computerized analysis of data and the interpretation of results are discussed.
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Affiliation(s)
- L D Claxton
- Environmental Carcinogenesis Division, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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Abstract
The first aim was to compare the genotoxicities of two tobacco-specific nitrosamines (TSNA), 4-(methylnitrosamino)-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) in two types of tests, the Salmonella reverse mutation assay (250-2000 microg per plate) and the Mutatox test (up to 1000 microg/ml) using dark mutant M-169 of Vibrio fischeri. The second aim was to assess the effects of single other tobacco chemicals and metabolites (nicotine (NIC), cotinine (COT), trans-3-hydroxycotinine (3HC), cotinine-N-oxide (CNO) and nicotine-N-oxide (NNO)) on the mutagenic responses at relative concentrations observed physiologically. The Salmonella strains were TA100, TA7004, TA7005, and TA7006, all showing missense backmutations that are characteristic of the TSNA. NNN was a direct mutagen to strains TA100, TA7004, and in the Mutatox test, and was not mutagenic in the presence of rat or hamster S9. NNK was mutagenic only in strain TA7004 with rat and hamster S9, but not in TA100, but was directly mutagenic in the Mutatox test. While all the other tobacco chemicals were not mutagenic alone to strains TA100 and TA7004 in the presence and absence of rat or hamster S9, the Mutatox test produced direct mutagenicity for COT, 3HC, and NNO, but not CNO. The latter was mutagenic in the Mutatox test with rat or hamster S9, but only rat S9 was effective for COT, NNO and 3HC. Inhibitory potentiations of NNN by NIC and COT were observed on strain TA7004, and by NIC on strain TA100. There were no interactions on NNK in the presence of S9 for strain TA7004 or TA100. In contrast, a complex inhibition and enhancement behavior occurred in the Mutatox test for each interaction, but no effects were observed for CNO on NNK without S9, and few for NIC on NNK with hamster S9. Compounds which showed no activity alone modulated the genotoxicity of two potent TSNAs in both types of tests.
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Affiliation(s)
- S H Yim
- Department of Environmental Health Sciences and Center for Occupational and Environmental Health, School of Public Health, University of California, 10833 Le Conte Avenue, Los Angeles 90095-1772, USA
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Flamand N, Meunier J, Meunier P, Agapakis-Caussé C. Mini mutagenicity test: a miniaturized version of the Ames test used in a prescreening assay for point mutagenesis assessment. Toxicol In Vitro 2001; 15:105-14. [PMID: 11287170 DOI: 10.1016/s0887-2333(01)00003-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The bacterial reverse mutagenicity test on Salmonella typhimurium, known as the Ames test, is widely used by regulatory agencies, academic institutions and chemical companies to assess the mutagenic potential of raw compounds. Several attempts have been made to miniaturise the Ames test in order to fit the industrial constraint of screening more products at the low quantities available. The major limitation of these miniaturised versions of the Ames test lies in the impossibility to work with all the six strains used in the regular Ames test, especially with those showing a low spontaneous revertant frequency. We describe here a mini version of the regulatory Ames test protocol that allows a significant reduction of the quantity of test substance needed (300 mg) but remains applicable to all Salmonella strains used in the regulatory protocol. In a preliminary study, 10 in-house chemical compounds have been evaluated in the Mini Mutagenicity Test (MMT) together with some positive control substances. A first set of historical data obtained in 1999 as well as the predictivity and the sensitivity of the MMT are presented and compared to those of the regular Ames test.
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Affiliation(s)
- N Flamand
- L'OREAL Advanced Research, Life Sciences Research, Investigative Toxicology Department, Aulnay-Sous-Bois, France.
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Abstract
The Ames Salmonella/microsome mutagenicity assay (Salmonella test; Ames test) is a short-term bacterial reverse mutation assay specifically designed to detect a wide range of chemical substances that can produce genetic damage that leads to gene mutations. The test employs several histidine dependent Salmonella strains each carrying different mutations in various genes in the histidine operon. These mutations act as hot spots for mutagens that cause DNA damage via different mechanisms. When the Salmonella tester strains are grown on a minimal media agar plate containing a trace of histidine, only those bacteria that revert to histidine independence (his(+)) are able to form colonies. The number of spontaneously induced revertant colonies per plate is relatively constant. However, when a mutagen is added to the plate, the number of revertant colonies per plate is increased, usually in a dose-related manner. The Ames test is used world-wide as an initial screen to determine the mutagenic potential of new chemicals and drugs. The test is also used for submission of data to regulatory agencies for registration or acceptance of many chemicals, including drugs and biocides. International guidelines have been developed for use by corporations and testing laboratories to ensure uniformity of testing procedures. This review provides historical aspects of how the Ames was developed and detailed procedures for performing the test, including the design and interpretation of results.
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Affiliation(s)
- K Mortelmans
- Molecular and Genetic Toxicology Program, SRI International, Menlo Park, CA 94025-3493, USA.
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Abu-Shakra A, McQueen ET, Cunningham ML. Rapid analysis of base-pair substitutions induced by mutagenic drugs through their oxygen radical or epoxide derivatives. Mutat Res 2000; 470:11-8. [PMID: 10986471 DOI: 10.1016/s1383-5718(00)00084-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Among the drugs that induce base-pair substitution mutations in the Salmonella reversion assay are the nitric oxide (NO)-delivery drug, diethylamine NONOate (DeaNO), and the ovarian cancer chemotherapeutic drug, treosulphan (TE). The present study compared the mutation spectra generated by DeaNO and TE in the hisG46 strains, TA1535 and TA100, the hisG428 strain, TA102, and the six Ames II 7000 series strains. Using these strains, it was feasible to conduct rapid analysis of the type and magnitude of induced mutation without resorting to DNA amplification and sequencing. A putative hydrolysis product of TE, 1,2:3,4-diepoxybutane (DEB), and hydrogen peroxide (H(2)O(2)) were included in the study to allow for further comparisons between epoxide-induced damage and that induced by the hydroxyl radical. TE (0.93 micromole/pl) induced 16. 8-fold-over-background reversion or a mutagenicity ratio (MR) of 16. 8 in TA1535. The response was weaker in TA100 (MR of 3), and negative in strain TA102. Only two Ames II strains demonstrated sensitivity to TE, and they were TA7004 (CG:AT) and TA7005 (GC:AT). Like TE, DeaNO (33 micromole/pl) was mutagenic in TA1535 (MR of 24.6), TA100 (MR of 5.3), TA7004 (MR of 13.7), and TA7005 (MR of 7.7), and non-mutagenic in TA102. These results showed a preferential sensitivity to reversion of the -CCC-target in TA100 and TA1535, and a lack of sensitivity to reversion of the -TAA-target in TA102. In addition, they elucidated the selectivity of the Ames II strains, with AT targets showing little or no sensitivity to reversion. The TE-epoxide derivative DEB was mutagenic in TA1535 and TA7004, but in contrast to TE, DEB was mutagenic in TA102. Interestingly, TA102 was reverted by DEB and H(2)O(2) but not by TE or DeaNO. This study showed that analysis of mutations is achievable using the battery of strains listed above. The fact that DNA damage can be detected by reversion at specific bases offers a tool for understanding the mechanisms through which drugs may exert their DNA and cellular damage.
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Affiliation(s)
- A Abu-Shakra
- Department of Biology, North Carolina Central University, 1801 Fayetteville Street, Durham, NC 27707, USA.
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Piegorsch WW, Simmons SJ, Margolin BH, Zeiger E, Gidrol XM, Gee P. Statistical modeling and analyses of a base-specific Salmonella mutagenicity assay. Mutat Res 2000; 467:11-9. [PMID: 10771267 DOI: 10.1016/s1383-5718(00)00019-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Statistical features of a base-specific Salmonella mutagenicity assay are considered in detail, following up on a previous report comparing responses of base-specific Salmonella (Ames II) strains with those of traditional tester strains. In addition to using different Salmonella strains, the new procedure also differs in that it is performed as a microwell fluctuation test, as opposed to the standard plate or preincubation test. This report describes the statistical modeling of data obtained from the use of these new strains in the microwell test procedure. We emphasize how to assess any significant interactions between replicate cultures and exposure doses, and how to identify a significant increase in the mutagenic response to a series of concentrations of a test substance.
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Affiliation(s)
- W W Piegorsch
- Department of Statistics, University of South Carolina, 216 LeConte College, Columbia, SC 29208, USA.
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Atamna H, Paler-Martínez A, Ames BN. N-t-butyl hydroxylamine, a hydrolysis product of alpha-phenyl-N-t-butyl nitrone, is more potent in delaying senescence in human lung fibroblasts. J Biol Chem 2000; 275:6741-8. [PMID: 10702229 DOI: 10.1074/jbc.275.10.6741] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alpha-phenyl-N-t-butyl nitrone (PBN), a spin trap, scavenges hydroxyl radicals, protects tissues from oxidative injury, and delays senescence of both normal human lung fibroblasts (IMR90) and senescence-accelerated mice. N-t-butyl hydroxylamine and benzaldehyde are the breakdown products of PBN. N-t-Butyl hydroxylamine delays senescence of IMR90 cells at concentrations as low as 10 microM compared with 200 microM PBN to produce a similar effect, suggesting that N-t-butyl hydroxylamine is the active form of PBN. N-Benzyl hydroxylamine and N-methyl hydroxylamine compounds unrelated to PBN were also effective in delaying senescence, suggesting the active functional group is the N-hydroxylamine. All the N-hydroxylamines tested significantly decreased the endogenous production of oxidants, as measured by the oxidation of 2', 7'-dichlorodihydrofluorescin and the increase in the GSH/GSSG ratio. The acceleration of senescence induced by hydrogen peroxide is reversed by the N-hydroxylamines. DNA damage, as determined by the level of apurinic/apyrimidinic sites, also decreased significantly following treatment with N-hydroxylamines. The N-hydroxylamines appear to be effective through mitochondria; they delay age-dependent changes in mitochondria as measured by accumulation of rhodamine-123, they prevent reduction of cytochrome C(FeIII) by superoxide radical, and they reverse an age-dependent decay of mitochondrial aconitase, suggesting they react with the superoxide radical.
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Affiliation(s)
- H Atamna
- Division of Biochemistry and Molecular Biology, Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA
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