Search

Your search keyword '"Zhang, Fagen"' showing total 202 results
Start Over Author "Zhang, Fagen"
202 results on '"Zhang, Fagen"'

2. Surface cleavage and electron donation mechanism of emerging contaminants excited by H_2O_2 assisted Cu-based catalyst

Author

SUN Yingtao, LIN Yehong, CAI Xuanying, ZHANG Zhitai, ZHANG Fagen, HU Chun, and LYU Lai

Subjects
dual-reaction-center, trace h_2o_2 assistance, preferential removal of ecs, contaminant electron donor effect, dissolved oxygen activation, Renewable energy sources, TJ807-830, Environmental protection, TD169-171.8
Abstract

Toxic emerging contaminants (ECs) and non-toxic dissolved organic matter (DOM) are present in the source water. The key to purification of source water is to realize low cost and efficient priority removal of toxic emerging contaminants. To break this bottleneck, Cu and Al metal species were modulated in situ into a dual reaction centers (DRCs) catalyst (CA-CN) with surface electronrich/-poor microregions in this work, and the catalyst was applied to the removal of trace ECs in water. It showed that CA-CN had excellent degradation performance for various trace ECs with the assistance of trace amounts of H_2O_2, especially for BPA, which could be removed over 80% within 5 minutes. In addition, preferential removal of ECs was achieved in the actual source waters configured with trace ECs. Series of characterization techniques showed that ECs acted as electron donors, and interface interaction occurred through π-π structures with electron-poor centers on the catalyst surface and transfer electrons, and then the electrons were transferred to electron-rich centers via C—O—M (metal species) bond bridges on the catalyst surface, activating H_2O_2 and dissolved oxygen adsorbed therein. The more important role of H_2O_2 in the whole process was to trigger the chain reaction of degrading ECs. This discovery breaks through the bottleneck of traditional source water purification and provides a direction for development of new high-efficiency and low-consumption water purification processes.

Published
2023
Full Text
View/download PDF

4. Towards best use and regulatory acceptance of generic physiologically based kinetic (PBK) models for in vitro-to-in vivo extrapolation (IVIVE) in chemical risk assessment

Author

Najjar, Abdulkarim, Punt, Ans, Wambaugh, John, Paini, Alicia, Ellison, Corie, Fragki, Styliani, Bianchi, Enrica, Zhang, Fagen, Westerhout, Joost, Mueller, Dennis, Li, Hequn, Shi, Quan, Gant, Timothy W., Botham, Phil, Bars, Rémi, Piersma, Aldert, van Ravenzwaay, Ben, and Kramer, Nynke I.

Published
2022
Full Text
View/download PDF

20. In vitro and in vivo assessments of the genotoxic potential of 3‐chloroallyl alcohol.

Author

Redmond, Aisling, Zhang, Fagen, Cheng, WanYun, and Gollapudi, B. Bhaskar

Subjects
BROMOMETHANE, AMES test, TERMINATION of treatment, HERBICIDE application, FUMIGANTS, BONE marrow, NUCLEOLUS
Abstract

3‐Chloroallyl alcohol (3‐CAA) can be found in the environment following the application of plant protection products. 3‐CAA is formed in groundwater following the injection of 1,3‐dichloropropene, a fumigant used to control nematodes. 3‐CAA is also formed, in leafy crops, as a glycoside conjugate following application of the herbicide, clethodim. Human exposure may occur from groundwater used as drinking water or through dietary consumption. To characterize 3‐CAA's potential to cause genotoxicity in mammals, in vitro and in vivo studies were conducted. 3‐CAA was negative in an Ames test and positive in a mouse lymphoma forward mutation assay. 3‐CAA was negative in an acute in vivo CD‐1 mouse bone marrow micronucleus assay when administered up to a dose level of 125 mg/kg/day for two consecutive days. In a combined gene mutation assay and erythrocyte micronucleus assay, using transgenic Big Blue® Fischer 344 rats, 3‐CAA was administered via drinking water at targeted dose levels of 0, 10, 30, and 100 mg/kg/day for 29 days. Peripheral blood samples, collected at the end of treatment, were analyzed for micronucleus induction in reticulocytes using flow cytometry. Liver and bone marrow samples, collected 2 days after the termination of the treatment, were analyzed for the induction of mutations at the cII locus. 3‐CAA did not induce an increase in mutant frequency or micronuclei under the experimental conditions. In conclusion, the mutagenic response observed in the in vitro mouse lymphoma assay is not confirmed in the whole animal. 3‐CAA is not considered to pose a mutagenic risk. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

22. Erratum: CATMoS: Collaborative Acute Toxicity Modeling Suite

Author

Mansouri, Kamel, primary, Karmaus, Agnes L., additional, Fitzpatrick, Jeremy, additional, Patlewicz, Grace, additional, Pradeep, Prachi, additional, Alberga, Domenico, additional, Alepee, Nathalie, additional, Allen, Timothy E.H., additional, Allen, Dave, additional, Alves, Vinicius M., additional, Andrade, Carolina H., additional, Auernhammer, Tyler R., additional, Ballabio, Davide, additional, Bell, Shannon, additional, Benfenati, Emilio, additional, Bhattacharya, Sudin, additional, Bastos, Joyce V., additional, Boyd, Stephen, additional, Brown, J. B., additional, Capuzzi, Stephen J., additional, Chushak, Yaroslav, additional, Ciallella, Heather, additional, Clark, Alex M., additional, Consonni, Viviana, additional, Daga, Pankaj R., additional, Ekins, Sean, additional, Farag, Sherif, additional, Fedorov, Maxim, additional, Fourches, Denis, additional, Gadaleta, Domenico, additional, Gao, Feng, additional, Gearhart, Jeffery M., additional, Goh, Garett, additional, Goodman, Jonathan M., additional, Grisoni, Francesca, additional, Grulke, Christopher M., additional, Hartung, Thomas, additional, Hirn, Matthew, additional, Karpov, Pavel, additional, Korotcov, Alexandru, additional, Lavado, Giovanna J., additional, Lawless, Michael, additional, Li, Xinhao, additional, Luechtefeld, Thomas, additional, Lunghini, Filippo, additional, Mangiatordi, Giuseppe F., additional, Marcou, Gilles, additional, Marsh, Dan, additional, Martin, Todd, additional, Mauri, Andrea, additional, Muratov, Eugene N., additional, Myatt, Glenn J., additional, Nguyen, Dac-Trung, additional, Nicolotti, Orazio, additional, Note, Reine, additional, Pande, Paritosh, additional, Parks, Amanda K., additional, Peryea, Tyler, additional, Polash, Ahsan H., additional, Rallo, Robert, additional, Roncaglioni, Alessandra, additional, Rowlands, Craig, additional, Ruiz, Patricia, additional, Russo, Daniel P., additional, Sayed, Ahmed, additional, Sayre, Risa, additional, Sheils, Timothy, additional, Siegel, Charles, additional, Silva, Arthur C., additional, Simeonov, Anton, additional, Sosnin, Sergey, additional, Southall, Noel, additional, Strickland, Judy, additional, Tang, Yun, additional, Teppen, Brian, additional, Tetko, Igor V., additional, Thomas, Dennis, additional, Tkachenko, Valery, additional, Todeschini, Roberto, additional, Toma, Cosimo, additional, Tripodi, Ignacio, additional, Trisciuzzi, Daniela, additional, Tropsha, Alexander, additional, Varnek, Alexandre, additional, Vukovic, Kristijan, additional, Wang, Zhongyu, additional, Wang, Liguo, additional, Waters, Katrina M., additional, Wedlake, Andrew J., additional, Wijeyesakere, Sanjeeva J., additional, Wilson, Dan, additional, Xiao, Zijun, additional, Yang, Hongbin, additional, Zahoranszky-Kohalmi, Gergely, additional, Zakharov, Alexey V., additional, Zhang, Fagen F., additional, Zhang, Zhen, additional, Zhao, Tongan, additional, Zhu, Hao, additional, Zorn, Kimberley M., additional, Casey, Warren, additional, and Kleinstreuer, Nicole C., additional

Published
2021
Full Text
View/download PDF

24. CATMoS: Collaborative Acute Toxicity Modeling Suite

Author

Mansouri, K, Karmaus, A, Fitzpatrick, J, Patlewicz, G, Pradeep, P, Alberga, D, Alepee, N, Allen, T, Allen, D, Alves, V, Andrade, C, Auernhammer, T, Ballabio, D, Bell, S, Benfenati, E, Bhattacharya, S, Bastos, J, Boyd, S, Brown, J, Capuzzi, S, Chushak, Y, Ciallella, H, Clark, A, Consonni, V, Daga, P, Ekins, S, Farag, S, Fedorov, M, Fourches, D, Gadaleta, D, Gao, F, Gearhart, J, Goh, G, Goodman, J, Grisoni, F, Grulke, C, Hartung, T, Hirn, M, Karpov, P, Korotcov, A, Lavado, G, Lawless, M, Li, X, Luechtefeld, T, Lunghini, F, Mangiatordi, G, Marcou, G, Marsh, D, Martin, T, Mauri, A, Muratov, E, Myatt, G, Nguyen, D, Nicolotti, O, Note, R, Pande, P, Parks, A, Peryea, T, Polash, A, Rallo, R, Roncaglioni, A, Rowlands, C, Ruiz, P, Russo, D, Sayed, A, Sayre, R, Sheils, T, Siegel, C, Silva, A, Simeonov, A, Sosnin, S, Southall, N, Strickland, J, Tang, Y, Teppen, B, Tetko, I, Thomas, D, Tkachenko, V, Todeschini, R, Toma, C, Tripodi, I, Trisciuzzi, D, Tropsha, A, Varnek, A, Vukovic, K, Wang, Z, Wang, L, Waters, K, Wedlake, A, Wijeyesakere, S, Wilson, D, Xiao, Z, Yang, H, Zahoranszky-Kohalmi, G, Zakharov, A, Zhang, F, Zhang, Z, Zhao, T, Zhu, H, Zorn, K, Casey, W, Kleinstreuer, N, Mansouri, Kamel, Karmaus, Agnes L, Fitzpatrick, Jeremy, Patlewicz, Grace, Pradeep, Prachi, Alberga, Domenico, Alepee, Nathalie, Allen, Timothy E H, Allen, Dave, Alves, Vinicius M, Andrade, Carolina H, Auernhammer, Tyler R, Ballabio, Davide, Bell, Shannon, Benfenati, Emilio, Bhattacharya, Sudin, Bastos, Joyce V, Boyd, Stephen, Brown, J B, Capuzzi, Stephen J, Chushak, Yaroslav, Ciallella, Heather, Clark, Alex M, Consonni, Viviana, Daga, Pankaj R, Ekins, Sean, Farag, Sherif, Fedorov, Maxim, Fourches, Denis, Gadaleta, Domenico, Gao, Feng, Gearhart, Jeffery M, Goh, Garett, Goodman, Jonathan M, Grisoni, Francesca, Grulke, Christopher M, Hartung, Thomas, Hirn, Matthew, Karpov, Pavel, Korotcov, Alexandru, Lavado, Giovanna J, Lawless, Michael, Li, Xinhao, Luechtefeld, Thomas, Lunghini, Filippo, Mangiatordi, Giuseppe F, Marcou, Gilles, Marsh, Dan, Martin, Todd, Mauri, Andrea, Muratov, Eugene N, Myatt, Glenn J, Nguyen, Dac-Trung, Nicolotti, Orazio, Note, Reine, Pande, Paritosh, Parks, Amanda K, Peryea, Tyler, Polash, Ahsan H, Rallo, Robert, Roncaglioni, Alessandra, Rowlands, Craig, Ruiz, Patricia, Russo, Daniel P, Sayed, Ahmed, Sayre, Risa, Sheils, Timothy, Siegel, Charles, Silva, Arthur C, Simeonov, Anton, Sosnin, Sergey, Southall, Noel, Strickland, Judy, Tang, Yun, Teppen, Brian, Tetko, Igor V, Thomas, Dennis, Tkachenko, Valery, Todeschini, Roberto, Toma, Cosimo, Tripodi, Ignacio, Trisciuzzi, Daniela, Tropsha, Alexander, Varnek, Alexandre, Vukovic, Kristijan, Wang, Zhongyu, Wang, Liguo, Waters, Katrina M, Wedlake, Andrew J, Wijeyesakere, Sanjeeva J, Wilson, Dan, Xiao, Zijun, Yang, Hongbin, Zahoranszky-Kohalmi, Gergely, Zakharov, Alexey V, Zhang, Fagen F, Zhang, Zhen, Zhao, Tongan, Zhu, Hao, Zorn, Kimberley M, Casey, Warren, Kleinstreuer, Nicole C, Mansouri, K, Karmaus, A, Fitzpatrick, J, Patlewicz, G, Pradeep, P, Alberga, D, Alepee, N, Allen, T, Allen, D, Alves, V, Andrade, C, Auernhammer, T, Ballabio, D, Bell, S, Benfenati, E, Bhattacharya, S, Bastos, J, Boyd, S, Brown, J, Capuzzi, S, Chushak, Y, Ciallella, H, Clark, A, Consonni, V, Daga, P, Ekins, S, Farag, S, Fedorov, M, Fourches, D, Gadaleta, D, Gao, F, Gearhart, J, Goh, G, Goodman, J, Grisoni, F, Grulke, C, Hartung, T, Hirn, M, Karpov, P, Korotcov, A, Lavado, G, Lawless, M, Li, X, Luechtefeld, T, Lunghini, F, Mangiatordi, G, Marcou, G, Marsh, D, Martin, T, Mauri, A, Muratov, E, Myatt, G, Nguyen, D, Nicolotti, O, Note, R, Pande, P, Parks, A, Peryea, T, Polash, A, Rallo, R, Roncaglioni, A, Rowlands, C, Ruiz, P, Russo, D, Sayed, A, Sayre, R, Sheils, T, Siegel, C, Silva, A, Simeonov, A, Sosnin, S, Southall, N, Strickland, J, Tang, Y, Teppen, B, Tetko, I, Thomas, D, Tkachenko, V, Todeschini, R, Toma, C, Tripodi, I, Trisciuzzi, D, Tropsha, A, Varnek, A, Vukovic, K, Wang, Z, Wang, L, Waters, K, Wedlake, A, Wijeyesakere, S, Wilson, D, Xiao, Z, Yang, H, Zahoranszky-Kohalmi, G, Zakharov, A, Zhang, F, Zhang, Z, Zhao, T, Zhu, H, Zorn, K, Casey, W, Kleinstreuer, N, Mansouri, Kamel, Karmaus, Agnes L, Fitzpatrick, Jeremy, Patlewicz, Grace, Pradeep, Prachi, Alberga, Domenico, Alepee, Nathalie, Allen, Timothy E H, Allen, Dave, Alves, Vinicius M, Andrade, Carolina H, Auernhammer, Tyler R, Ballabio, Davide, Bell, Shannon, Benfenati, Emilio, Bhattacharya, Sudin, Bastos, Joyce V, Boyd, Stephen, Brown, J B, Capuzzi, Stephen J, Chushak, Yaroslav, Ciallella, Heather, Clark, Alex M, Consonni, Viviana, Daga, Pankaj R, Ekins, Sean, Farag, Sherif, Fedorov, Maxim, Fourches, Denis, Gadaleta, Domenico, Gao, Feng, Gearhart, Jeffery M, Goh, Garett, Goodman, Jonathan M, Grisoni, Francesca, Grulke, Christopher M, Hartung, Thomas, Hirn, Matthew, Karpov, Pavel, Korotcov, Alexandru, Lavado, Giovanna J, Lawless, Michael, Li, Xinhao, Luechtefeld, Thomas, Lunghini, Filippo, Mangiatordi, Giuseppe F, Marcou, Gilles, Marsh, Dan, Martin, Todd, Mauri, Andrea, Muratov, Eugene N, Myatt, Glenn J, Nguyen, Dac-Trung, Nicolotti, Orazio, Note, Reine, Pande, Paritosh, Parks, Amanda K, Peryea, Tyler, Polash, Ahsan H, Rallo, Robert, Roncaglioni, Alessandra, Rowlands, Craig, Ruiz, Patricia, Russo, Daniel P, Sayed, Ahmed, Sayre, Risa, Sheils, Timothy, Siegel, Charles, Silva, Arthur C, Simeonov, Anton, Sosnin, Sergey, Southall, Noel, Strickland, Judy, Tang, Yun, Teppen, Brian, Tetko, Igor V, Thomas, Dennis, Tkachenko, Valery, Todeschini, Roberto, Toma, Cosimo, Tripodi, Ignacio, Trisciuzzi, Daniela, Tropsha, Alexander, Varnek, Alexandre, Vukovic, Kristijan, Wang, Zhongyu, Wang, Liguo, Waters, Katrina M, Wedlake, Andrew J, Wijeyesakere, Sanjeeva J, Wilson, Dan, Xiao, Zijun, Yang, Hongbin, Zahoranszky-Kohalmi, Gergely, Zakharov, Alexey V, Zhang, Fagen F, Zhang, Zhen, Zhao, Tongan, Zhu, Hao, Zorn, Kimberley M, Casey, Warren, and Kleinstreuer, Nicole C

Abstract

Background: Humans are exposed to tens of thousands of chemical substances that need to be assessed for their potential toxicity. Acute systemic toxicity testing serves as the basis for regulatory hazard classification, labeling, and risk management. However, it is cost- and time-prohibitive to evaluate all new and existing chemicals using traditional rodent acute toxicity tests. In silica models built using existing data facilitate rapid acute tox- icity predictions without using animals. Objkctivks: The U.S. Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) Acute Toxicity Workgroup organ- ized an international collaboration to develop in silica models for predicting acute oral toxicity based on five different end points: Lethal Dose 50 (LD50 value, U.S. Environmental Protection Agency hazard (four) categories, Globally Harmonized System for Classification and Labeling hazard (five) categories, very toxic chemicals [LD50 (LD50 ≤ 50 mg/kg)], and nontoxic chemicals (LD50 > 2,000 mg/kg). Mkthods: An acute oral toxicity data inventory for 11,992 chemicals was compiled, split into training and evaluation sets, and made available to 35 participating international research groups that submitted a total of 139 predictive models. Predictions that fell within the applicability domains of the submitted models were evaluated using external validation sets. These were then combined into consensus models to leverage strengths of individual approaches. Results: The resulting consensus predictions, which leverage the collective strengths of each individual model, form the Collaborative Acute Toxicity Modeling Suite (CATMoS). CATMoS demonstrated high performance in terms of accuracy and robustness when compared with in viva results. Discussion: CATMoS is being evaluated by regulatory agencies for its utility and applicability as a potential replacement for in viva rat acute oral toxicity studies. CATMoS predictions for more than 800,000 chemica

Published
2021

25. CATMoS: Collaborative Acute Toxicity Modeling Suite

Author

Mansouri, Kamel, primary, Karmaus, Agnes L., additional, Fitzpatrick, Jeremy, additional, Patlewicz, Grace, additional, Pradeep, Prachi, additional, Alberga, Domenico, additional, Alepee, Nathalie, additional, Allen, Timothy E.H., additional, Allen, Dave, additional, Alves, Vinicius M., additional, Andrade, Carolina H., additional, Auernhammer, Tyler R., additional, Ballabio, Davide, additional, Bell, Shannon, additional, Benfenati, Emilio, additional, Bhattacharya, Sudin, additional, Bastos, Joyce V., additional, Boyd, Stephen, additional, Brown, J.B., additional, Capuzzi, Stephen J., additional, Chushak, Yaroslav, additional, Ciallella, Heather, additional, Clark, Alex M., additional, Consonni, Viviana, additional, Daga, Pankaj R., additional, Ekins, Sean, additional, Farag, Sherif, additional, Fedorov, Maxim, additional, Fourches, Denis, additional, Gadaleta, Domenico, additional, Gao, Feng, additional, Gearhart, Jeffery M., additional, Goh, Garett, additional, Goodman, Jonathan M., additional, Grisoni, Francesca, additional, Grulke, Christopher M., additional, Hartung, Thomas, additional, Hirn, Matthew, additional, Karpov, Pavel, additional, Korotcov, Alexandru, additional, Lavado, Giovanna J., additional, Lawless, Michael, additional, Li, Xinhao, additional, Luechtefeld, Thomas, additional, Lunghini, Filippo, additional, Mangiatordi, Giuseppe F., additional, Marcou, Gilles, additional, Marsh, Dan, additional, Martin, Todd, additional, Mauri, Andrea, additional, Muratov, Eugene N., additional, Myatt, Glenn J., additional, Nguyen, Dac-Trung, additional, Nicolotti, Orazio, additional, Note, Reine, additional, Pande, Paritosh, additional, Parks, Amanda K., additional, Peryea, Tyler, additional, Polash, Ahsan H., additional, Rallo, Robert, additional, Roncaglioni, Alessandra, additional, Rowlands, Craig, additional, Ruiz, Patricia, additional, Russo, Daniel P., additional, Sayed, Ahmed, additional, Sayre, Risa, additional, Sheils, Timothy, additional, Siegel, Charles, additional, Silva, Arthur C., additional, Simeonov, Anton, additional, Sosnin, Sergey, additional, Southall, Noel, additional, Strickland, Judy, additional, Tang, Yun, additional, Teppen, Brian, additional, Tetko, Igor V., additional, Thomas, Dennis, additional, Tkachenko, Valery, additional, Todeschini, Roberto, additional, Toma, Cosimo, additional, Tripodi, Ignacio, additional, Trisciuzzi, Daniela, additional, Tropsha, Alexander, additional, Varnek, Alexandre, additional, Vukovic, Kristijan, additional, Wang, Zhongyu, additional, Wang, Liguo, additional, Waters, Katrina M., additional, Wedlake, Andrew J., additional, Wijeyesakere, Sanjeeva J., additional, Wilson, Dan, additional, Xiao, Zijun, additional, Yang, Hongbin, additional, Zahoranszky-Kohalmi, Gergely, additional, Zakharov, Alexey V., additional, Zhang, Fagen F., additional, Zhang, Zhen, additional, Zhao, Tongan, additional, Zhu, Hao, additional, Zorn, Kimberley M., additional, Casey, Warren, additional, and Kleinstreuer, Nicole C., additional

Published
2021
Full Text
View/download PDF

33. Biogas Potential for Improved Sustainability in Guangzhou, China : A Study Focusing on Food Waste on Xiaoguwei Island

Author

Feiz, Roozbeh, Ammenberg, Jonas, Björn, Annika, Yufang, Guo, Karlsson, Magnus, Liu, Yonghui, Liu, Yuxian, Masuda, Laura Shizue Moriga, Enrich-Prast, Alex, Rohracher, Harald, Trygg, Kristina, Shakeri Yekta, Sepehr, Zhang, Fagen, Feiz, Roozbeh, Ammenberg, Jonas, Björn, Annika, Yufang, Guo, Karlsson, Magnus, Liu, Yonghui, Liu, Yuxian, Masuda, Laura Shizue Moriga, Enrich-Prast, Alex, Rohracher, Harald, Trygg, Kristina, Shakeri Yekta, Sepehr, and Zhang, Fagen

Abstract

As a result of rapid development in China and the growth of megacities, large amounts of organic wastes are generated within relatively small areas. Part of these wastes can be used to produce biogas, not only to reduce waste-related problems, but also to provide renewable energy, recycle nutrients, and lower greenhouse gases and air polluting emissions. This article is focused on the conditions for biogas solutions in Guangzhou. It is based on a transdisciplinary project that integrates several approaches, for example, literature studies and lab analysis of food waste to estimate the food waste potential, interviews to learn about the socio-technical context and conditions, and life-cycle assessment to investigate the performance of different waste management scenarios involving biogas production. Xiaoguwei Island, with a population of about 250,000 people, was chosen as the area of study. The results show that there are significant food waste potentials on the island, and that all studied scenarios could contribute to a net reduction of greenhouse gas emissions. Several socio-technical barriers were identified, but it is expected that the forthcoming regulatory changes help to overcome some of them., Funding agencies: Linkoping University-Guangzhou University Research Center on Urban Sustainable Development by Guangzhou City; Training Program for Excellent Young Teachers in Guangdong Universities [YQ2015125]

Published
2019
Full Text
View/download PDF

35. Biogas Potential for Improved Sustainability in Guangzhou, China—A Study Focusing on Food Waste on Xiaoguwei Island

Author

Feiz, Roozbeh, primary, Ammenberg, Jonas, additional, Björn, Annika, additional, Guo, Yufang, additional, Karlsson, Magnus, additional, Liu, Yonghui, additional, Liu, Yuxian, additional, Shizue Moriga Masuda, Laura, additional, Enrich-Prast, Alex, additional, Rohracher, Harald, additional, Trygg, Kristina, additional, Shakeri Yekta, Sepehr, additional, and Zhang, Fagen, additional

Published
2019
Full Text
View/download PDF

37. Investigation of potential early key events and mode of action for 1,2‐dichloroethane‐induced mammary tumors in female rats.

Author

LeBaron, Matthew J., Hotchkiss, Jon A., Zhang, Fagen, Koehler, Matthew W., and Boverhof, Darrell R.

Subjects
DNA adducts, MAMMARY glands, CHLOROHYDROCARBONS, RATS, DNA damage, POLYVINYL chloride
Abstract

1,2‐dichloroethane (DCE or EDC) is a chlorinated hydrocarbon used as a chemical intermediate, including in the synthesis of polyvinyl chloride. Although DCE has induced tumors in both rats and mice, the overall weight‐of‐evidence suggests a lack of in vivo mutagenicity. The present study was conducted to explore a potential mode of action further for tumor formation in rat mammary tissue. Fischer 344 rats were exposed to target concentrations of 0 or 200 ppm of DCE vapors (6 hours/day, 7 days/week) for at least 28 days; 200 ppm represents a concentration of ~20% higher than that reported to induce mammary tumors. Endpoints examined included DNA damage (via Comet assay), glutathione (reduced, oxidized and conjugated), tissue DNA adducts, cell proliferation and serum prolactin levels. Exposure to DCE did not alter serum prolactin levels with consistent estrous stage, did not cause cell proliferation in mammary epithelial cells, nor result in histopathological alterations in the mammary gland. DNA adducts were identified, including the N7‐guanylethyl glutathione adduct, with higher adduct levels measured in liver (nontumorigenic target) compared with mammary tissue isolated from the same rats; no known mutagenic adducts were identified. DCE did not increase the Comet assay response in mammary epithelial cells, whereas DNA damage in the positive control (N‐nitroso‐N‐methylurea) was significantly increased. Although the result of this study did not identify a specific mode of action for DCE‐induced mammary tumors in rats, the lack of any exposure‐related genotoxic responses further contributes to the weight‐of‐evidence suggesting that DCE is a nongenotoxic carcinogen. 1,2‐dichloroethane (DCE or EDC) is a chlorinated hydrocarbon used as a chemical intermediate, including in the synthesis of polyvinyl chloride. The present study was conducted to explore further the potential mode of action for tumor formation in rat mammary tissue. Although the results of this study do not identify a specific mode of action for DCE‐induced mammary tumors in rats, the lack of any exposure‐related genotoxic responses further contributes to the weight‐of‐evidence suggesting that DCE is a nongenotoxic carcinogen. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

44. An organizational approach for the assessment of DNA adduct data in risk assessment: case studies for aflatoxin B1, tamoxifen and vinyl chloride

Author

Pottenger, Lynn H., primary, Andrews, Larry S., additional, Bachman, Ammie N., additional, Boogaard, Peter J., additional, Cadet, Jean, additional, Embry, Michelle R., additional, Farmer, Peter B., additional, Himmelstein, Matthew W., additional, Jarabek, Annie M., additional, Martin, Elizabeth A., additional, Mauthe, Robert J., additional, Persaud, Rudranath, additional, Preston, R. Julian, additional, Schoeny, Rita, additional, Skare, Julie, additional, Swenberg, James A., additional, Williams, Gary M., additional, Zeiger, Errol, additional, Zhang, Fagen, additional, and Kim, James H., additional

Published
2014
Full Text
View/download PDF

45. Reaction of the premarin metabolite 4-hydroxyquilenin semiquinone radicals with 2'-deoxyguanosine: formation of unusual cyclic adducts

Author

Shen, Li, Qiu, Shengxiang, Van Breemen, Richard V., Zhang, Fagen, Chen, Yumei, and Bolton, Judy L.

Subjects
Radicals (Chemistry) -- Analysis, Carcinogenesis -- Research, Chemistry, Premarin (Medication) -- Adverse and side effects
Abstract

Synthesis of 2'-deoxyguanosine (dG) adducts of 4-hydroxyequilenin (4-OHEN) revealed that the semiquinone radical of this cathecol metabolite of equilenin forms unusual adducts with dG. Results indicate that the quinoid responsible for alkylation of dG under physiological conditions is the semiquinone radical that generates unusual adducts. The implications of these adducts on the biological effects of Premarin have not yet been defined.

Published
1997

Catalog

Books, media, physical & digital resources
See catalog results