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Sample records for vitro toxicity tests

  1. In vitro Toxicity Testing in the Twenty-First Century.

    Science.gov (United States)

    Roggen, Erwin L

    2011-01-01

    The National Research Council (NRC) article "Toxicity Testing in the 21st Century: A vision and A Strategy" (National Research Council, 2007) was written to bring attention to the application of scientific advances for use in toxicity tests so that chemicals can be tested in a more time and cost efficient manner while providing a more relevant and mechanistic insight into the toxic potential of a compound. Development of tools for in vitro toxicity testing constitutes an important activity of this vision and contributes to the provision of test systems as well as data that are essential for the development of computer modeling tools for, e.g., system biology, physiologically based modeling. This article intends to highlight some of the issues that have to be addressed in order to make in vitro toxicity testing a reality in the twenty-first century.

  2. In Vitro Toxicity testing in the 21st Century

    Directory of Open Access Journals (Sweden)

    Erwin L Roggen

    2011-02-01

    Full Text Available The National Research Council (NRC article Toxicity Testing in the 21st Century: A vision and A Strategy (National Research Council, 2007 was written to bring attention to the application of scientific advances for use in toxicity tests so that chemicals can be tested in a more time and cost efficient manner while providing a more relevant and mechanistic insight into the toxic potential of a compound.Development of tools for in vitro toxicity testing constitutes an important activity of this vision and contributes to the provision of test systems as well as data that are essential for the development of computer modelling tools for e.g. system biology, physiologically-based modelling. This article intends to highlight some of the issues that have to be addressed in order to make in vitro toxicity testing a reality in the 21st century.

  3. In vitro Cell Culture Model for Toxic Inhaled Chemical Testing

    Science.gov (United States)

    Ahmad, Shama; Ahmad, Aftab; Neeves, Keith B.; Hendry-Hofer, Tara; Loader, Joan E.; White, Carl W.; Veress, Livia

    2014-01-01

    Cell cultures are indispensable to develop and study efficacy of therapeutic agents, prior to their use in animal models. We have the unique ability to model well differentiated human airway epithelium and heart muscle cells. This could be an invaluable tool to study the deleterious effects of toxic inhaled chemicals, such as chlorine, that can normally interact with the cell surfaces, and form various byproducts upon reacting with water, and limiting their effects in submerged cultures. Our model using well differentiated human airway epithelial cell cultures at air-liqiuid interface circumvents this limitation as well as provides an opportunity to evaluate critical mechanisms of toxicity of potential poisonous inhaled chemicals. We describe enhanced loss of membrane integrity, caspase release and death upon toxic inhaled chemical such as chlorine exposure. In this article, we propose methods to model chlorine exposure in mammalian heart and airway epithelial cells in culture and simple tests to evaluate its effect on these cell types. PMID:24837339

  4. Screening of toxic potential of graphene family nanomaterials using in vitro and alternative in vivo toxicity testing systems.

    Science.gov (United States)

    Chatterjee, Nivedita; Yang, Ji Su; Park, Kwangsik; Oh, Seung Min; Park, Jeonggue; Choi, Jinhee

    2015-01-01

    The widely promising applications of graphene nanomaterials raise considerable concerns regarding their environmental and human health risk assessment. The aim of the current study was to evaluate the toxicity profiling of graphene family nananomaterials (GFNs) in alternative in vitro and in vivo toxicity testing models. The GFNs used in this study are graphene nanoplatelets ([GNPs]-pristine, carboxylate [COOH] and amide [NH2]) and graphene oxides (single layer [SLGO] and few layers [FLGO]). The human bronchial epithelial cells (Beas2B cells) as in vitro system and the nematode Caenorhabditis elegans as in vivo system were used to profile the toxicity response of GFNs. Cytotoxicity assays, colony formation assay for cellular toxicity and reproduction potentiality in C. elegans were used as end points to evaluate the GFNs' toxicity. In general, GNPs exhibited higher toxicity than GOs in Beas2B cells, and among the GNPs the order of toxicity was pristine>NH2>COOH. Although the order of toxicity of the GNPs was maintained in C. elegans reproductive toxicity, but GOs were found to be more toxic in the worms than GNPs. In both systems, SLGO exhibited profoundly greater dose dependency than FLGO. The possible reason of their differential toxicity lay in their distinctive physicochemical characteristics and agglomeration behavior in the exposure media. The present study revealed that the toxicity of GFNs is dependent on the graphene nanomaterial's physical forms, surface functionalizations, number of layers, dose, time of exposure and obviously, on the alternative model systems used for toxicity assessment.

  5. Toxicity testing: the search for an in vitro alternative to animal testing.

    Science.gov (United States)

    May, J E; Xu, J; Morse, H R; Avent, N D; Donaldson, C

    2009-01-01

    Prior to introduction to the clinic, pharmaceuticals must undergo rigorous toxicity testing to ensure their safety. Traditionally, this has been achieved using in vivo animal models. However, besides ethical reasons, there is a continual drive to reduce the number of animals used for this purpose due to concerns such as the lack of concordance seen between animal models and toxic effects in humans. Adequate testing to ensure any toxic metabolites are detected can be further complicated if the agent is administered in a prodrug form, requiring a source of cytochrome P450 enzymes for metabolism. A number of sources of metabolic enzymes have been utilised in in vitro models, including cell lines, primary human tissue and liver extracts such as S9. This review examines current and new in vitro models for toxicity testing, including a new model developed within the authors' laboratory utilising HepG2 liver spheroids within a co-culture system to examine the effects of chemotherapeutic agents on other cell types.

  6. Interpreting in vitro developmental toxicity test battery results: The consideration of toxicokinetics

    NARCIS (Netherlands)

    Bosgra, S.; Westerhout, J.

    2015-01-01

    In the EU collaborative project ChemScreen an alternative, in vitro assay-based test strategy was developed to screen compounds for reproductive toxicity. A toxicokinetic modeling approach was used to allow quantitative comparison between effective concentrations in the in vitro test battery and

  7. In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles.

    NARCIS (Netherlands)

    Park, M.V.; Annema, W.; Salvati, A.; Lesniak, A.; Elsaesser, A.; Barnes, C.; McKerr, G.; Howard, C.; Lynch, I.; Dawson, K.; Piersma, A.H.; de Jong, W.H.

    2009-01-01

    While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining

  8. The role of in vitro methods as alternatives to animals in toxicity testing.

    Science.gov (United States)

    Anadón, Arturo; Martínez, María Aranzazu; Castellano, Victor; Martínez-Larrañaga, María Rosa

    2014-01-01

    It is accepted that animal testing should be reduced, refined or replaced as far as it is practicably possible. There are also a wide variety of in vitro models, which are used as screening studies and mechanistic investigations. The ability of an in vitro assay to be reliable, biomedically, is essential in pharmaceutical development. Furthermore, it is necessary that cells used in in vitro testing mimic the phenotype of cells within the human target tissue. The focus of this review article is to identify the key points of in vitro assays. In doing so, the authors take into account the chemical agents that are assessed and the integrated in vitro testing strategies. There is a transfer of toxicological data from primary in vivo animal studies to in vitro assays. The key element for designing an integrated in vitro testing strategy is summarized as follows: exposure modeling of chemical agents for in vitro testing; data gathering, sharing and read-across for testing a class of chemical; a battery of tests to assemble a broad spectrum of data on different mechanisms of action to predict toxic effects; and applicability of the test and the integrated in vitro testing strategies and flexibility to adjust the integrated in vitro testing strategies to test substance. While these methods will be invaluable if effective, more studies must be done to ensure reliability and suitability of these tests for humans.

  9. Toxicity testing: The search for an in vitro alternative to animal testing

    OpenAIRE

    May, J. E.; Xu, J.; Morse, R.; Avent, N; Donaldson, C

    2009-01-01

    Prior to introduction to the clinic, pharmaceuticals must\\ud undergo rigorous toxicity testing to ensure their safety.\\ud Traditionally, this has been achieved using in vivo animal\\ud models. However, besides ethical reasons, there is a\\ud continual drive to reduce the number of animals used for\\ud this purpose due to concerns such as the lack of\\ud concordance seen between animal models and toxic effects\\ud in humans. Adequate testing to ensure any toxic\\ud metabolites are detected can be fu...

  10. Comprehensive In Vitro Toxicity Testing of a Panel of Representative Oxide Nanomaterials: First Steps towards an Intelligent Testing Strategy.

    Science.gov (United States)

    Farcal, Lucian; Torres Andón, Fernando; Di Cristo, Luisana; Rotoli, Bianca Maria; Bussolati, Ovidio; Bergamaschi, Enrico; Mech, Agnieszka; Hartmann, Nanna B; Rasmussen, Kirsten; Riego-Sintes, Juan; Ponti, Jessica; Kinsner-Ovaskainen, Agnieszka; Rossi, François; Oomen, Agnes; Bos, Peter; Chen, Rui; Bai, Ru; Chen, Chunying; Rocks, Louise; Fulton, Norma; Ross, Bryony; Hutchison, Gary; Tran, Lang; Mues, Sarah; Ossig, Rainer; Schnekenburger, Jürgen; Campagnolo, Luisa; Vecchione, Lucia; Pietroiusti, Antonio; Fadeel, Bengt

    2015-01-01

    Nanomaterials (NMs) display many unique and useful physico-chemical properties. However, reliable approaches are needed for risk assessment of NMs. The present study was performed in the FP7-MARINA project, with the objective to identify and evaluate in vitro test methods for toxicity assessment in order to facilitate the development of an intelligent testing strategy (ITS). Six representative oxide NMs provided by the EC-JRC Nanomaterials Repository were tested in nine laboratories. The in vitro toxicity of NMs was evaluated in 12 cellular models representing 6 different target organs/systems (immune system, respiratory system, gastrointestinal system, reproductive organs, kidney and embryonic tissues). The toxicity assessment was conducted using 10 different assays for cytotoxicity, embryotoxicity, epithelial integrity, cytokine secretion and oxidative stress. Thorough physico-chemical characterization was performed for all tested NMs. Commercially relevant NMs with different physico-chemical properties were selected: two TiO2 NMs with different surface chemistry - hydrophilic (NM-103) and hydrophobic (NM-104), two forms of ZnO - uncoated (NM-110) and coated with triethoxycapryl silane (NM-111) and two SiO2 NMs produced by two different manufacturing techniques - precipitated (NM-200) and pyrogenic (NM-203). Cell specific toxicity effects of all NMs were observed; macrophages were the most sensitive cell type after short-term exposures (24-72h) (ZnO>SiO2>TiO2). Longer term exposure (7 to 21 days) significantly affected the cell barrier integrity in the presence of ZnO, but not TiO2 and SiO2, while the embryonic stem cell test (EST) classified the TiO2 NMs as potentially 'weak-embryotoxic' and ZnO and SiO2 NMs as 'non-embryotoxic'. A hazard ranking could be established for the representative NMs tested (ZnO NM-110 > ZnO NM-111 > SiO2 NM-203 > SiO2 NM-200 > TiO2 NM-104 > TiO2 NM-103). This ranking was different in the case of embryonic tissues, for which TiO2

  11. Comprehensive In Vitro Toxicity Testing of a Panel of Representative Oxide Nanomaterials: First Steps towards an Intelligent Testing Strategy.

    Directory of Open Access Journals (Sweden)

    Lucian Farcal

    Full Text Available Nanomaterials (NMs display many unique and useful physico-chemical properties. However, reliable approaches are needed for risk assessment of NMs. The present study was performed in the FP7-MARINA project, with the objective to identify and evaluate in vitro test methods for toxicity assessment in order to facilitate the development of an intelligent testing strategy (ITS. Six representative oxide NMs provided by the EC-JRC Nanomaterials Repository were tested in nine laboratories. The in vitro toxicity of NMs was evaluated in 12 cellular models representing 6 different target organs/systems (immune system, respiratory system, gastrointestinal system, reproductive organs, kidney and embryonic tissues. The toxicity assessment was conducted using 10 different assays for cytotoxicity, embryotoxicity, epithelial integrity, cytokine secretion and oxidative stress. Thorough physico-chemical characterization was performed for all tested NMs. Commercially relevant NMs with different physico-chemical properties were selected: two TiO2 NMs with different surface chemistry - hydrophilic (NM-103 and hydrophobic (NM-104, two forms of ZnO - uncoated (NM-110 and coated with triethoxycapryl silane (NM-111 and two SiO2 NMs produced by two different manufacturing techniques - precipitated (NM-200 and pyrogenic (NM-203. Cell specific toxicity effects of all NMs were observed; macrophages were the most sensitive cell type after short-term exposures (24-72h (ZnO>SiO2>TiO2. Longer term exposure (7 to 21 days significantly affected the cell barrier integrity in the presence of ZnO, but not TiO2 and SiO2, while the embryonic stem cell test (EST classified the TiO2 NMs as potentially 'weak-embryotoxic' and ZnO and SiO2 NMs as 'non-embryotoxic'. A hazard ranking could be established for the representative NMs tested (ZnO NM-110 > ZnO NM-111 > SiO2 NM-203 > SiO2 NM-200 > TiO2 NM-104 > TiO2 NM-103. This ranking was different in the case of embryonic tissues, for which TiO2

  12. Multi-parameter in vitro toxicity testing of crizotinib, sunitinib, erlotinib, and nilotinib in human cardiomyocytes

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, Kimberly R., E-mail: kimberly.doherty@quintiles.com [Quintiles, 777 Oakmont Lane Suite 100, Westmont, IL 60559 (United States); Wappel, Robert L.; Talbert, Dominique R.; Trusk, Patricia B.; Moran, Diarmuid M. [Quintiles, 777 Oakmont Lane Suite 100, Westmont, IL 60559 (United States); Kramer, James W.; Brown, Arthur M. [ChanTest Corporation, 14656 Neo Parkway, Cleveland, OH 44128 (United States); Shell, Scott A.; Bacus, Sarah [Quintiles, 777 Oakmont Lane Suite 100, Westmont, IL 60559 (United States)

    2013-10-01

    Tyrosine kinase inhibitors (TKi) have greatly improved the treatment and prognosis of multiple cancer types. However, unexpected cardiotoxicity has arisen in a subset of patients treated with these agents that was not wholly predicted by pre-clinical testing, which centers around animal toxicity studies and inhibition of the human Ether-à-go-go-Related Gene (hERG) channel. Therefore, we sought to determine whether a multi-parameter test panel assessing the effect of drug treatment on cellular, molecular, and electrophysiological endpoints could accurately predict cardiotoxicity. We examined how 4 FDA-approved TKi agents impacted cell viability, apoptosis, reactive oxygen species (ROS) generation, metabolic status, impedance, and ion channel function in human cardiomyocytes. The 3 drugs clinically associated with severe cardiac adverse events (crizotinib, sunitinib, nilotinib) all proved to be cardiotoxic in our in vitro tests while the relatively cardiac-safe drug erlotinib showed only minor changes in cardiac cell health. Crizotinib, an ALK/MET inhibitor, led to increased ROS production, caspase activation, cholesterol accumulation, disruption in cardiac cell beat rate, and blockage of ion channels. The multi-targeted TKi sunitinib showed decreased cardiomyocyte viability, AMPK inhibition, increased lipid accumulation, disrupted beat pattern, and hERG block. Nilotinib, a second generation Bcr-Abl inhibitor, led to increased ROS generation, caspase activation, hERG block, and an arrhythmic beat pattern. Thus, each drug showed a unique toxicity profile that may reflect the multiple mechanisms leading to cardiotoxicity. This study demonstrates that a multi-parameter approach can provide a robust characterization of drug-induced cardiomyocyte damage that can be leveraged to improve drug safety during early phase development. - Highlights: • TKi with known adverse effects show unique cardiotoxicity profiles in this panel. • Crizotinib increases ROS, apoptosis, and

  13. Testing strategies for embryo-fetal toxicity of human pharmaceuticals. Animal models vs. in vitro approaches: a workshop report.

    Science.gov (United States)

    van der Laan, Jan Willem; Chapin, Robert E; Haenen, Bert; Jacobs, Abigail C; Piersma, Aldert

    2012-06-01

    Reproductive toxicity testing is characterized by high animal use. For registration of pharmaceutical compounds, developmental toxicity studies are usually conducted in both rat and rabbits. Efforts have been underway for a long time to design alternatives to animal use. Implementation has lagged, partly because of uncertainties about the applicability domain of the alternatives. The reproductive cycle is complex and not all mechanisms of development can be mimicked in vitro. Therefore, efforts are underway to characterize the available alternative tests with regard to the mechanism of action they include. One alternative test is the mouse embryonic stem cell test (EST), which has been studied since the late 1990s. It is a genuine 3R "alternative" assay as it is essentially animal-free. A meeting was held to review the state-of-the-art of various in vitro models for prediction of developmental toxicity. Although the predictivity of individual assays is improving, a battery of several assays is likely to have even higher predictivity, which is necessary for regulatory acceptance. The workshop concluded that an important first step is a thorough survey of the existing rat and rabbit studies, to fully characterize the frequency of responses and the types of effects seen. At the same time, it is important to continue the optimization of in vitro assays. As more experience accumulates, the optimal conditions, assay structure, and applicability of the alternative assays are expected to emerge. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Rapid toxicity assessment of sediments from estuarine ecosystems: A new tandem in vitro testing approach

    Science.gov (United States)

    Johnson, B. Thomas; Long, E.R.

    1998-01-01

    Microtox?? and Mutatox?? were used to evaluate the acute toxicity and genotoxicity, respectively, of organic sediment extracts from Pensacola Bay and St. Andrew Bay, two estuaries that cover about 273 and 127 km2, respectively, along the Gulf coast of Florida, USA. The sensitivity and selectivity of these two bioluminescent toxicity assays were demonstrated in validation studies with over 50 pesticides, genotoxins, and industrial pollutants, both as single compounds and in complex mixtures. The 50% effective concentration (EC50) values of insecticides, petroleum products, and polychlorinated biphenyls determined by Microtox all tended to group around the mean EC50 value of 1.2 (0.8) mg/L. The polycyclic aromatic hydrocarbon sensitivity of Mutatox was in general similar to that reported in the Ames test. Surficial sediment samples were collected, extracted with dichloromethane, evaporated and concentrated under nitrogen, dissolved in dimethyl sulfoxide, assayed for acute toxicity and genotoxicity, and compared with reference sediments. Samples with low EC50 values, and determined to be genotoxic, were detected in Massalina Bayou, Watson Bayou, East Bay, and St. Andrew Bay-East in St. Andrew Bay as well as Bayou Grande, Bayou Chico, and Bayou Texar in Pensacola Bay. An overview of these data sets analyzed by Spearman rank correlation showed a significant correlation between acute toxicity and genotoxicity (p < 0.05). Microtox and Mutatox in tandem was a sensitive, cost-effective, and rapid (<24 h) screening tool that identified troublesome areas of pollution and assessed the potential sediment toxicity of lipophilic contaminants in aquatic ecosystems.

  15. In vitro to in vivo extrapolation of effective dosimetry in developmental toxicity testing: Application of a generic PBK modelling approach.

    Science.gov (United States)

    Fragki, Styliani; Piersma, Aldert H; Rorije, Emiel; Zeilmaker, Marco J

    2017-10-01

    Incorporation of kinetics to quantitative in vitro to in vivo extrapolations (QIVIVE) is a key step for the realization of a non-animal testing paradigm, in the sphere of regulatory toxicology. The use of Physiologically-Based Kinetic (PBK) modelling for determining systemic doses of chemicals at the target site is accepted to be an indispensable element for such purposes. Nonetheless, PBK models are usually designed for a single or a group of compounds and are considered demanding, with respect to experimental data needed for model parameterization. Alternatively, we evaluate here the use of a more generic approach, i.e. the so-called IndusChemFate model, which is based on incorporated QSAR model parametrization. The model was used to simulate the in vivo kinetics of three diverse classes of developmental toxicants: triazoles, glycol ethers' alkoxyacetic acid metabolites and phthalate primary metabolites. The model required specific input per each class of compounds. These compounds were previously tested in three alternative assays: the whole-embryo culture (WEC), the zebrafish embryo test (ZET), and the mouse embryonic stem cell test (EST). Thereafter, the PBK-simulated blood levels at toxic in vivo doses were compared to the respective in vitro effective concentrations. Comparisons pertaining to relative potency and potency ranking with integration of kinetics were similar to previously obtained comparisons. Additionally, all three in vitro systems produced quite comparable results, and hence, a combination of alternative tests is still preferable for predicting the endpoint of developmental toxicity in vivo. This approach is put forward as biologically more plausible since plasma concentrations, rather than external administered doses, constitute the most direct in vivo dose metric. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Rapid in vitro tests to determine the toxicity of raw wastewater and ...

    African Journals Online (AJOL)

    2012-09-18

    Sep 18, 2012 ... Chemosphere 51 539–543. KENDIG D and TARLOFF J (2007) Inactivation of lactate dehydro- genase by several chemicals: Implications for in vitro toxicology studies. Toxicol. In Vitro 21 125–132. KIRBY M, MORRIS S, HURST M, KIRBY S, NEALL P, TYLOR T and FAGG A (2000) The use of cholinesterase ...

  17. Biocompatibility study of two diblock copolymeric nanoparticles for biomedical applications by in vitro toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Goñi-de-Cerio, Felipe [GAIKER Technology Centre (Spain); Mariani, Valentina [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Cohen, Dror [Dead Sea Laboratories, AHAVA (Israel); Madi, Lea [Tel-Aviv University, Department of Physiology and Pharmacology, Sackler School of Medicine (Israel); Thevenot, Julie; Oliveira, Hugo [ENSCPB, Université de Bordeaux (France); Uboldi, Chiara; Giudetti, Guido; Coradeghini, Rosella [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Garanger, Elisabeth [ENSCPB, Université de Bordeaux (France); Rossi, François [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Portugal-Cohen, Meital; Oron, Miriam [Dead Sea Laboratories, AHAVA (Israel); Korenstein, Rafi [Tel-Aviv University, Department of Physiology and Pharmacology, Sackler School of Medicine (Israel); Lecommandoux, Sébastien [ENSCPB, Université de Bordeaux (France); Ponti, Jessica [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Suárez-Merino, Blanca; Heredia, Pedro, E-mail: heredia@gaiker.es [GAIKER Technology Centre (Spain)

    2013-11-15

    Drugs used for chemotherapy normally carry out adverse, undesired effects. Nanotechnology brings about new horizons to tackle cancer disease with a different strategy. One of the most promising approaches is the use of nanocarriers to transport active drugs. These nanocarriers need to have special properties to avoid immune responses and toxicity, and it is critical to study these effects. Nanocarriers may have different nature, but polypeptide-based copolymers have attracted considerable attention for their biocompatibility, controlled and slow biodegradability as well as low toxicity. Little has been done regarding specific nanocarriers toxicity. In this study, we performed a thorough toxicological study of two different block copolymer nanoparticles (NPs); poly(trimethylene carbonate)-block–poly(l-glutamic acid) (PTMC-b–PGA) and poly(ethylene glycol)-block–poly(γ-benzyl-l-glutamate) (PEG-b–PBLG) with sizes between 113 and 131 nm. Low blood–serum–protein interaction was observed. Moreover, general toxicity assays and other endpoints (apoptosis or necrosis) showed good biocompatibility for both NPs. Reactive oxygen species increased in only two cell lines (HepG2 and TK6) in the presence of PTMC-b–PGA. Cytokine production study showed cytokine induction only in one cell line (A549). We also performed the same assays on human skin organ culture before and after UVB light treatment, with a moderate toxicity after treatment independent of NPs presence or absence. Interleukin 1 induction was also observed due to the combined effect of PEG-b–PBLG and UVB light irradiation. Future in vivo studies for biocompatibility and toxicity will provide more valuable information, but, so far, the findings presented here suggest the possibility of using these two NPs as nanocarriers for nanomedical applications, always taking into account the application procedure and the way in which they are implemented.

  18. Biocompatibility study of two diblock copolymeric nanoparticles for biomedical applications by in vitro toxicity testing

    Science.gov (United States)

    Goñi-de-Cerio, Felipe; Mariani, Valentina; Cohen, Dror; Madi, Lea; Thevenot, Julie; Oliveira, Hugo; Uboldi, Chiara; Giudetti, Guido; Coradeghini, Rosella; Garanger, Elisabeth; Rossi, François; Portugal-Cohen, Meital; Oron, Miriam; Korenstein, Rafi; Lecommandoux, Sébastien; Ponti, Jessica; Suárez-Merino, Blanca; Heredia, Pedro

    2013-11-01

    Drugs used for chemotherapy normally carry out adverse, undesired effects. Nanotechnology brings about new horizons to tackle cancer disease with a different strategy. One of the most promising approaches is the use of nanocarriers to transport active drugs. These nanocarriers need to have special properties to avoid immune responses and toxicity, and it is critical to study these effects. Nanocarriers may have different nature, but polypeptide-based copolymers have attracted considerable attention for their biocompatibility, controlled and slow biodegradability as well as low toxicity. Little has been done regarding specific nanocarriers toxicity. In this study, we performed a thorough toxicological study of two different block copolymer nanoparticles (NPs); poly(trimethylene carbonate)- block-poly( l-glutamic acid) (PTMC- b-PGA) and poly(ethylene glycol)- block-poly( γ-benzyl- l-glutamate) (PEG- b-PBLG) with sizes between 113 and 131 nm. Low blood-serum-protein interaction was observed. Moreover, general toxicity assays and other endpoints (apoptosis or necrosis) showed good biocompatibility for both NPs. Reactive oxygen species increased in only two cell lines (HepG2 and TK6) in the presence of PTMC- b-PGA. Cytokine production study showed cytokine induction only in one cell line (A549). We also performed the same assays on human skin organ culture before and after UVB light treatment, with a moderate toxicity after treatment independent of NPs presence or absence. Interleukin 1 induction was also observed due to the combined effect of PEG- b-PBLG and UVB light irradiation. Future in vivo studies for biocompatibility and toxicity will provide more valuable information, but, so far, the findings presented here suggest the possibility of using these two NPs as nanocarriers for nanomedical applications, always taking into account the application procedure and the way in which they are implemented.

  19. Rapid in vitro tests to determine the toxicity of raw wastewater and ...

    African Journals Online (AJOL)

    2012-09-18

    Sep 18, 2012 ... toxicity of raw wastewater and treated sewage effluents from 3 sewage treatment plants in the Western Cape, South Africa. Raw wastewater ... Raw wastewater from all sewage treatment plants contained AChE inhibitors and sewage treatment ..... BOUSSETTA H (2009) Acute effects of chlorpyrifos-ethyl and.

  20. Assessment of a new cell culture perfusion apparatus for in vitro chronic toxicity testing. Part 1 : technical description

    NARCIS (Netherlands)

    Koppelstaetter, Christian; Jennings, Paul; Ryan, Michael P; Morin, Jean-Paul; Hartung, Thomas; Pfaller, Walter

    2004-01-01

    In vitro models for chronic toxicity, defined as a recurring exposure to compounds over a prolonged period of time, are still underrepresented in drug evaluation processes. The classical approach to cell culture is not readily suitable to long term repetitive applications. Therefore, we assessed the

  1. The future of toxicity testing.

    Science.gov (United States)

    Andersen, Melvin E; Al-Zoughool, Mustafa; Croteau, Maxine; Westphal, Margit; Krewski, Daniel

    2010-02-01

    In 2007, the U.S. National Research Council (NRC) released a report, "Toxicity Testing in the 21st Century: A Vision and a Strategy," that proposes a paradigm shift for toxicity testing of environmental agents. The vision is based on the notion that exposure to environmental agents leads to adverse health outcomes through the perturbation of toxicity pathways that are operative in humans. Implementation of the NRC vision will involve a fundamental change in the assessment of toxicity of environmental agents, moving away from adverse health outcomes observed in experimental animals to the identification of critical perturbations of toxicity pathways. Pathway perturbations will be identified using in vitro assays and quantified for dose response using methods in computational toxicology and other recent scientific advances in basic biology. Implementation of the NRC vision will require a major research effort, not unlike that required to successfully map the human genome, extending over 10 to 20 years, involving the broad scientific community to map important toxicity pathways operative in humans. This article provides an overview of the scientific tools and technologies that will form the core of the NRC vision for toxicity testing. Of particular importance will be the development of rapidly performed in vitro screening assays using human cells and cell lines or human tissue surrogates to efficiently identify environmental agents producing critical pathway perturbations. In addition to the overview of the NRC vision, this study documents the reaction by a number of stakeholder groups since 2007, including the scientific, risk assessment, regulatory, and animal welfare communities.

  2. Relative developmental toxicity potencies of retinoids in the embryonic stem cell test compared with their relative potencies in in vivo and two other in vitro assays for developmental toxicity

    NARCIS (Netherlands)

    Louisse, J.; Gönen, S.; Rietjens, I.M.C.M.; Verwei, M.

    2011-01-01

    The present study determines the relative developmental toxicity potencies of retinoids in the embryonic stem (ES)-D3 cell differentiation assay of the embryonic stem cell test, and compares the outcomes with their relative potencies in in vivo and two other in vitro assays for developmental

  3. In Vitro Toxicity Assessment Technique for Volatile ...

    Science.gov (United States)

    The U.S. Environmental Protection Agency is tasked with evaluating the human health, environmental, and wildlife effects of over 80,000 chemicals registered for use in the environment and commerce. The challenge is that sparse chemical data exists; traditional toxicity testing methods are slow, costly, involve animal studies, and cannot keep up with a chemical registry that typically grows by at least 1000 chemicals every year. In recent years, High Throughput Screening (HTS) has been used in order to prioritize chemicals for traditional toxicity screening or to complement traditional toxicity studies. HTS is an in vitro approach of rapidly assaying a large number of chemicals for biochemical activity using robotics and automation. However, no method currently exists for screening volatile chemicals such as air pollutants in a HTS fashion. Additionally, significant uncertainty regarding in vitro to in in vivo extrapolation (IVIVE) remains. An approach to bridge the IVIVE gap and the current lack of ability to screen volatile chemicals in a HTS fashion is by using a probe molecule (PrM) technique. The proposed technique uses chemicals with empirical human pharmacokinetic data as PrMs to study toxicity of molecules with no known data for gas-phase analysis. We are currently studying the xenobiotic-metabolizing enzyme CYP2A6 using transfected BEAS-2B bronchial epithelial cell line. The CYP2A6 pathway activity is studied by the formation of cotinine from nicot

  4. In vitro toxicity screening of colored smokes

    NARCIS (Netherlands)

    Langenberg, J.P.; Alblas, M.J.; Makkus, J.C.; Meer, J.A. van der; Mars-Groenendijk, R.H.; Groeneveld, F.R.; Norbert, M.; Lingen, J.N.J. van

    2009-01-01

    Data on the acute and/or long-term toxicity of colored smokes appear to be scarce and inconsistent. Therefore, the objective of this study is to obtain more insight on this matter. For this purpose, existing platforms for in vitro toxicity screening are evaluated with respect to their applicability

  5. In vitro toxicity test of ethyl 2-cyanoacrylate, a tissue adhesive used in cardiovascular surgery, by fibroblast cell culture method.

    Science.gov (United States)

    Kaplan, Mehmet; Baysal, Kemal

    2005-01-01

    The aim of this study was to evaluate the cytotoxicity of cyanoacrylate polymers (ethyl 2-cyanoacrylate) by an elution test system. In such systems, the material is extracted with a cell culture medium, which is subsequently added onto cultured cells, resulting in an indirect contact between the biomaterial and cells. A cell line commonly utilized for cytotoxicity experiments; L929 mouse fibroblasts were used in this study. The effects of extract dilutions on cells were evaluated by two experiments: (a) The cells were suspended and seeded in a medium containing the extract, followed by a short incubation to observe the effects on cell attachment; (b) cells were seeded in a normal medium. Following cell attachment, this was replaced with a medium containing the extract and long-term effects on cell proliferation were measured. The cytotoxicity was quantified using a cell viability assay, well established for use in the evaluation of cell-biomaterial interactions. These results indicate that, in the test system utilized, a tenfold dilution of the extract results in an approximately 10% decrease in cells; this increases to between 30% and 45% in a 1:1 dilution. When a large number of cells (3000/well) were used, proliferation of cells overcame the cytotoxic effect and consistent results could not be observed. In this study, the observed outcomes follow a similar trend on cell attachment and proliferation with acute effects (4 hours incubation) of the extracts on the cells, producing slightly higher toxicity. Our findings are parallel with the literature findings.

  6. Psi-screen, an in vitro toxicity test system: applications in the bioassay of perfumes and fragrance chemicals.

    Science.gov (United States)

    Griffiths, David E

    2005-10-01

    The effects of 65 perfume formulations (perfume oils, perfumes, eau de parfum, eau de toilette) on mitochondrial membrane potential (Psim) and mitochondrial respiration have been investigated using a mitochondria-based assay for (Psim, termed Psi-Screen. All the perfume formulations tested are highly active in the Psi-Screen assay, and the major site of inhibition in all cases is NADH-ubiquinone reductase (Complex I). This is confirmed in studies on the inhibition of NADH oxidase and NADH-ubiquinone reductase. Some formulations also inhibit succinate oxidation at either Complex II or Complex III. Evidence for the inhibition of mitochondrial ATPase is presented, as well as for the induction of reactive oxygen species production by perfume inhibition of Complex I. Thus, perfume formulations are multiple inhibitor mixtures which inhibit multiple bioenergetic functions at high dilutions. The implications of these findings are discussed with respect to cell toxicity via necrosis and/or apoptosis. Twenty candidate fragrance chemicals were investigated and all inhibited Complex I (5 at <35 microM). Mass screening strategies and high-throughput screening assays are discussed.

  7. Toxicity of Ag, CuO and ZnO nanoparticles to selected environmentally relevant test organisms and mammalian cells in vitro: a critical review.

    Science.gov (United States)

    Bondarenko, Olesja; Juganson, Katre; Ivask, Angela; Kasemets, Kaja; Mortimer, Monika; Kahru, Anne

    2013-07-01

    Nanoparticles (NPs) of copper oxide (CuO), zinc oxide (ZnO) and especially nanosilver are intentionally used to fight the undesirable growth of bacteria, fungi and algae. Release of these NPs from consumer and household products into waste streams and further into the environment may, however, pose threat to the 'non-target' organisms, such as natural microbes and aquatic organisms. This review summarizes the recent research on (eco)toxicity of silver (Ag), CuO and ZnO NPs. Organism-wise it focuses on key test species used for the analysis of ecotoxicological hazard. For comparison, the toxic effects of studied NPs toward mammalian cells in vitro were addressed. Altogether 317 L(E)C50 or minimal inhibitory concentrations (MIC) values were obtained for algae, crustaceans, fish, bacteria, yeast, nematodes, protozoa and mammalian cell lines. As a rule, crustaceans, algae and fish proved most sensitive to the studied NPs. The median L(E)C50 values of Ag NPs, CuO NPs and ZnO NPs (mg/L) were 0.01, 2.1 and 2.3 for crustaceans; 0.36, 2.8 and 0.08 for algae; and 1.36, 100 and 3.0 for fish, respectively. Surprisingly, the NPs were less toxic to bacteria than to aquatic organisms: the median MIC values for bacteria were 7.1, 200 and 500 mg/L for Ag, CuO and ZnO NPs, respectively. In comparison, the respective median L(E)C50 values for mammalian cells were 11.3, 25 and 43 mg/L. Thus, the toxic range of all the three metal-containing NPs to target- and non-target organisms overlaps, indicating that the leaching of biocidal NPs from consumer products should be addressed.

  8. Induced pluripotent stem cell-derived limbal epithelial cells (LiPSC) as a cellular alternative for in vitro ocular toxicity testing.

    Science.gov (United States)

    Aberdam, Edith; Petit, Isabelle; Sangari, Linda; Aberdam, Daniel

    2017-01-01

    Induced pluripotent stem cells hold great potential to produce unlimited amount of differentiated cells as cellular source for regenerative medicine but also for in vitro drug screening and cytotoxicity tests. Ocular toxicity testing is mandatory to evaluate the risks of drugs and cosmetic products before their application to human patients by preventing eye irritation or insult. Since the global ban to use animals, many human-derived alternatives have been proposed, from ex-vivo enucleated postmortem cornea, primary corneal cell culture and immortalized corneal epithelial cell lines. All of them share limitations for their routine use. Using an improved protocol, we derived limbal epithelial cells from human induced pluripotent stem cells, named LiPSC, that are able to be passaged and differentiate further into corneal epithelial cells. Comparative RT-qPCR, immunofluorescence staining, flow cytometry analysis and zymography assays demonstrate that LiPSC are morphologically and molecularly similar to the adult stem cells. Moreover, contrary to HCE, LiPSC and primary limbal cells display similarly sensitive to cytotoxicity treatment among passages. Our data strongly suggest that LiPSC could become a powerful alternative cellular model for cosmetic and drug tests.

  9. THE FUTURE OF TOXICITY TESTING AND ASSESSMENT ...

    Science.gov (United States)

    The National Research Council's Board on Environmental Studies and Toxicology is conducting a two-part study to assess and advance current approaches to toxicity testing and assessment to meet regulatory data needs. The first part of the study was completed January 2006, in which the committee prepared a report reviewing selected aspects of several relevant reports by EPA and others on this topic. In the second part of the study currently underway, the committee will prepare a final report presenting a long-range vision and strategic plan for advancing the practices of toxicity testing and human health assessment for environmental contaminants. In developing the vision and strategic plan, the committee will consider evolving regulatory data needs; current toxicity testing guidelines and standards used by EPA and other federal agencies; the use of emerging science and tools (e.g., genomics, proteomics, transgenics, bioinformatics, computational toxicology, in vitro testing, and other alternatives to animal testing); and the challenges of incorporating more complex understanding of toxicity (e.g., toxicokinetics, mechanisms of action, systems biology) into human health risk assessment. The final report is expected to be released as early as the end of January, 2007. To develop a long-range vision and strategic plan for advancing the practices of toxicity testing and human health assessment for environmental contaminants.

  10. The C. elegans model in toxicity testing.

    Science.gov (United States)

    Hunt, Piper Reid

    2017-01-01

    Caenorhabditis elegans is a small nematode that can be maintained at low cost and handled using standard in vitro techniques. Unlike toxicity testing using cell cultures, C. elegans toxicity assays provide data from a whole animal with intact and metabolically active digestive, reproductive, endocrine, sensory and neuromuscular systems. Toxicity ranking screens in C. elegans have repeatedly been shown to be as predictive of rat LD50 ranking as mouse LD50 ranking. Additionally, many instances of conservation of mode of toxic action have been noted between C. elegans and mammals. These consistent correlations make the case for inclusion of C. elegans assays in early safety testing and as one component in tiered or integrated toxicity testing strategies, but do not indicate that nematodes alone can replace data from mammals for hazard evaluation. As with cell cultures, good C. elegans culture practice (GCeCP) is essential for reliable results. This article reviews C. elegans use in various toxicity assays, the C. elegans model's strengths and limitations for use in predictive toxicology, and GCeCP. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Journal of Applied Toxicology published by John Wiley & Sons Ltd. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Journal of Applied Toxicology published by John Wiley & Sons Ltd.

  11. A Miniscale Algal Toxicity Test

    DEFF Research Database (Denmark)

    Arensberg, Pia; Hemmingsen, Vicky H.; Nyholm, Niels

    1995-01-01

    A simple miniscale (approx. 1 - 2.5 ml) toxicity test procedure with the freshwater green algaSelenastrum capricornutum is described. The procedure fulfils the validity criteria of the ISO (International Association for Standardization) standard test protocol. Practically identical concentration...... and test volumes (down to 1 ml) could also be used. Tissue culture treated polystyrene microplates were found toxic to algae and thus unusable. pH control is achieved more easily in the minitest than in larger size shake flasks due to greater turbulence and a larger surface/volume ratio which both...... facilitates CO2 mass transfer. Uniform illumination of the individual units of a minitest setup is obtained readily due to the small area that has to be illuminated. Using the rapidly growing green alga S. capricornutum as test organism, it is proposed generally to reduce the standard test duration from 3...

  12. Comparative In vivo, Ex vivo, and In vitro Toxicity Studies of Engineered Nanomaterials

    Science.gov (United States)

    Efforts to reduce the number of animals in engineered nanomaterials (ENM) toxicity testing have resulted in the development of numerous alternative toxicity testing methods, but in vivo and in vitro results are still evolving and variable. This inconsistency could be due to the f...

  13. Microfluidics for Antibiotic Susceptibility and Toxicity Testing

    Directory of Open Access Journals (Sweden)

    Jing Dai

    2016-10-01

    Full Text Available The recent emergence of antimicrobial resistance has become a major concern for worldwide policy makers as very few new antibiotics have been developed in the last twenty-five years. To prevent the death of millions of people worldwide, there is an urgent need for a cheap, fast and accurate set of tools and techniques that can help to discover and develop new antimicrobial drugs. In the past decade, microfluidic platforms have emerged as potential systems for conducting pharmacological studies. Recent studies have demonstrated that microfluidic platforms can perform rapid antibiotic susceptibility tests to evaluate antimicrobial drugs’ efficacy. In addition, the development of cell-on-a-chip and organ-on-a-chip platforms have enabled the early drug testing, providing more accurate insights into conventional cell cultures on the drug pharmacokinetics and toxicity, at the early and cheaper stage of drug development, i.e., prior to animal and human testing. In this review, we focus on the recent developments of microfluidic platforms for rapid antibiotics susceptibility testing, investigating bacterial persistence and non-growing but metabolically active (NGMA bacteria, evaluating antibiotic effectiveness on biofilms and combinatorial effect of antibiotics, as well as microfluidic platforms that can be used for in vitro antibiotic toxicity testing.

  14. In vitro assessments of nanomaterial toxicity.

    Science.gov (United States)

    Jones, Clinton F; Grainger, David W

    2009-06-21

    Nanotechnology has grown from a scientific interest to a major industry with both commodity and specialty nanomaterial exposure to global populations and ecosystems. Sub-micron materials are currently used in a wide variety of consumer products and in clinical trials as drug delivery carriers and imaging agents. Due to the expected growth in this field and the increasing public exposure to nanomaterials, both from intentional administration and inadvertent contact, improved characterization and reliable toxicity screening tools are required for new and existing nanomaterials. This review discusses current methodologies used to assess nanomaterial physicochemical properties and their in vitro effects. Current methods lack the desired sensitivity, reliability, correlation and sophistication to provide more than limited, often equivocal, pieces of the overall nanomaterial performance parameter space, particularly in realistic physiological or environmental models containing cells, proteins and solutes. Therefore, improved physicochemical nanomaterial assays are needed to provide accurate exposure risk assessments and genuine predictions of in vivo behavior and therapeutic value. Simpler model nanomaterial systems in buffer do not accurately duplicate this complexity or predict in vivo behavior. A diverse portfolio of complementary material characterization tools and bioassays are required to validate nanomaterial properties in physiology.

  15. Screening of toxic potential of graphene family nanomaterials using and alternative toxicity testing systems

    Directory of Open Access Journals (Sweden)

    Nivedita Chatterjee

    2015-07-01

    Full Text Available Objectives The widely promising applications of graphene nanomaterials raise considerable concerns regarding their environmental and human health risk assessment. The aim of the current study was to evaluate the toxicity profiling of graphene family nananomaterials (GFNs in alternative in vitro and in vivo toxicity testing models. Methods The GFNs used in this study are graphene nanoplatelets ([GNPs]–pristine, carboxylate [COOH] and amide [NH2] and graphene oxides (single layer [SLGO] and few layers [FLGO]. The human bronchial epithelial cells (Beas2B cells as in vitro system and the nematode Caenorhabditis elegans as in vivo system were used to profile the toxicity response of GFNs. Cytotoxicity assays, colony formation assay for cellular toxicity and reproduction potentiality in C. elegans were used as end points to evaluate the GFNs’ toxicity. Results In general, GNPs exhibited higher toxicity than GOs in Beas2B cells, and among the GNPs the order of toxicity was pristine>NH2>COOH. Although the order of toxicity of the GNPs was maintained in C. elegans reproductive toxicity, but GOs were found to be more toxic in the worms than GNPs. In both systems, SLGO exhibited profoundly greater dose dependency than FLGO. The possible reason of their differential toxicity lay in their distinctive physicochemical characteristics and agglomeration behavior in the exposure media. Conclusions The present study revealed that the toxicity of GFNs is dependent on the graphene nanomaterial’s physical forms, surface functionalizations, number of layers, dose, time of exposure and obviously, on the alternative model systems used for toxicity assessment.

  16. In vitro allergy testing.

    Science.gov (United States)

    Osguthorpe, John David

    2014-09-01

    History and physical examination are the first, and most important steps, in the evaluation of a patient suspected of having an allergy. The diagnosis can be confirmed with either skin or serum testing for evidence of immunoglobulin E (IgE)-mediated reactivity. The recent literature on serum-based testing for the detection and quantitation of allergen specific IgE (sIgE) was reviewed, identifying where available the "best practices" from high level of evidence studies and/or physician organization guidelines. Current practices for documenting sIgE are detailed, including enzyme-linked immunoassays on conventional extracts (standardized or not), similar on microarrays of highly purified or recombinant allergens, and basophil activation testing. Serum testing is an equal alternative to skin testing for establishing the presence of IgE-mediated sensitivity and for identifying the allergens involved. Like skin testing, limitations include the availability of fully detailed allergenic extracts, particularly for foods, drugs, and occupational agents, and the possibility of non-IgE mediated issues. © 2014 ARS-AAOA, LLC.

  17. BIOEQUIVALENCE APPROACH FOR WHOLE EFFLUENT TOXICITY TESTING

    Science.gov (United States)

    Increased use of whole effluent toxicity (WET) tests in the regulatory arena has brought increased concern over the statistical analysis of WET test data and the determination of toxicity. One concern is the issue of statistical power. A number of WET tests may pass the current...

  18. [Toxicity of antiseptics on chondrocytes in vitro].

    Science.gov (United States)

    Schaumburger, J; Beckmann, J; Springorum, H-R; Handel, M; Anders, S; Kalteis, T; Grifka, J; Rath, B

    2010-01-01

    Local antiseptics are commonly used for perioperative skin and wound disinfection and as solutions for joint lavage. Therefore, we examined if an intra-articular use of these antiseptics is possible by using an IN VITRO chondrocyte model. Articular chondrocytes harvested from 7 patients were cultured. After reaching 80% confluency different concentrations (0%, 1%, 10%, 50%, 100%) of polyhexanide, hydrogen peroxide and povidone-iodine were added for 5 minutes. Afterwards, the solution was removed and the chondrocytes were cultured for 24 hours. Subsequently the vitality and proliferation rate (DNA synthesis) were analysed with the WST-1 and BrdU tests. 1% povidone-iodine and 1% hydrogen peroxide solutions significantly (p=0.001) decreased the chondrocyte vitality as compared to our control group. There was no significant difference (p=0.71) after the application of 1% polyhexanide in the vitality ratios. A significant decrease in vitality was also observed after the application of 10% polyhexanide solution (p=0.001). Application of 1% povidone-iodine solution, 1% hydrogen peroxide solution and 10% polyhexanide revealed a decrease in the metabolic cell activity of 80% compared to our control group, whereas the activity was 65% (p=0.026) compared to the control group after application of 1% polyhexanide solution. Our results demonstrate the chondrotoxic effect of the tested antiseptic solutions in clinical used concentrations within short time points. Polyhexanide in a low concentrated solution (1%) was the antiseptic with the lowest influence on the vitality and the DNA synthesis of chondrocytes. Thus, this antiseptic solution seemed to be the best choice for intra-articular application. But overall, our study showed general limitations for the intra-articular use of local antiseptics. Copyright (c) Georg Thieme Verlag KG Stuttgart-New York.

  19. Prediction of acute inhalation toxicity using in vitro lung surfactant inhibition

    DEFF Research Database (Denmark)

    Sørli, Jorid Birkelund; Huang, Yishi; Da Silva, Emilie

    2018-01-01

    numbers and amounts and exhibit great variety. Therefore, an alternative method to screen for acute inhalation toxicity is needed. The aim of our study was to determine if inhibition of lung surfactant by impregnation products in vitro could accurately predict toxicity in vivo in mice. We tested 21...... the chemical composition of the products and induction of toxicity. The currently accepted method for determination of acute inhalation toxicity is based on experiments on animals; it is time-consuming, expensive and causes stress for the animals. Impregnation products are present on the market in large...... impregnation products using the constant flow through set-up of the constrained drop surfactometer to determine if they inhibited LS function or not. The same products were tested in a mouse inhalation bioassay to determine their toxicity in vivo. The sensitivity was 100%, i.e. the in vitro method predicted...

  20. Prediction of acute inhalation toxicity using in vitro lung surfactant inhibition

    DEFF Research Database (Denmark)

    Sørli, Jorid Birkelund; Huang, Yishi; Da Silva, Emilie

    2017-01-01

    Private consumers and professionals may experience acute inhalation toxicity after inhaling aerosolized impregnation products. The distinction between toxic and non-toxic products is difficult to make for producers and product users alike, as there is no clearly described relationship between...... the chemical composition of the products and induction of toxicity. The currently accepted method for determination of acute inhalation toxicity is based on experiments on animals; it is time-consuming, expensive and causes stress for the animals. Impregnation products are present on the market in large...... numbers and amounts and exhibit great variety. Therefore, an alternative method to screen for acute inhalation toxicity is needed. The aim of our study was to determine if inhibition of lung surfactant by impregnation products in vitro could accurately predict toxicity in vivo in mice. We tested 21...

  1. Organotypic liver culture models: meeting current challenges in toxicity testing.

    Science.gov (United States)

    LeCluyse, Edward L; Witek, Rafal P; Andersen, Melvin E; Powers, Mark J

    2012-07-01

    Prediction of chemical-induced hepatotoxicity in humans from in vitro data continues to be a significant challenge for the pharmaceutical and chemical industries. Generally, conventional in vitro hepatic model systems (i.e. 2-D static monocultures of primary or immortalized hepatocytes) are limited by their inability to maintain histotypic and phenotypic characteristics over time in culture, including stable expression of clearance and bioactivation pathways, as well as complex adaptive responses to chemical exposure. These systems are less than ideal for longer-term toxicity evaluations and elucidation of key cellular and molecular events involved in primary and secondary adaptation to chemical exposure, or for identification of important mediators of inflammation, proliferation and apoptosis. Progress in implementing a more effective strategy for in vitro-in vivo extrapolation and human risk assessment depends on significant advances in tissue culture technology and increasing their level of biological complexity. This article describes the current and ongoing need for more relevant, organotypic in vitro surrogate systems of human liver and recent efforts to recreate the multicellular architecture and hemodynamic properties of the liver using novel culture platforms. As these systems become more widely used for chemical and drug toxicity testing, there will be a corresponding need to establish standardized testing conditions, endpoint analyses and acceptance criteria. In the future, a balanced approach between sample throughput and biological relevance should provide better in vitro tools that are complementary with animal testing and assist in conducting more predictive human risk assessment.

  2. A comparison of standard acute toxicity tests with rapid-screening toxicity tests

    Energy Technology Data Exchange (ETDEWEB)

    Toussaint, M.W. [Geo-Centers, Inc., Fort Washington, MD (United States); Shedd, T.R. [Army Biomedical Research and Development Lab., Frederick, MD (United States); Schalie, W.H. van der [Environmental Protection Agency, Washington, DC (United States); Leather, G.R. [Hood Coll., Frederick, MD (United States). Dept. of Biology

    1995-05-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus calyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photobacterium phosphoreum--Microtox{reg_sign} test, and a mixture of bacterial species--the Polytox{reg_sign} test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriodaphnia dubia), green algae (Selenastrum capricornutum), fathead minnows (Pimephales promelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC50/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

  3. Toxicity test of a dental commercial composite

    OpenAIRE

    Ponce Bravo, Santa; Ledesma Montes, Constantino; Martínez Rivera, José Luis; Garcés Ortíz, Maricela

    2015-01-01

    Background International rules must be followed for testing biosecurity in dental materials. A new brand of restorative material appeared in the market and regulations indicated that it should be tested for toxicity. Objectives The aim of this study was to determine the 90-day sub chronic toxicity of one triethylene glycol dimethacrylate containing composite (MEDENTAL Light-Cure Composite?) orally administered to rats according to Organization for Economic Co-Operation and Development no. 48 ...

  4. The basis of toxicity testing

    National Research Council Canada - National Science Library

    Ecobichon, Donald J

    1992-01-01

    This book discusses fundamental principles and concepts behind toxicological tests, their design and implementation, interpretation of results, and significance of individual studies in the overall...

  5. Effects of solvents and dosing procedure on chemical toxicity in cell-based in vitro assays.

    NARCIS (Netherlands)

    Tanneberger, K.; Rico Rico, A.; Kramer, N.I.; Busser, F.J.M.; Hermens, J.L.M.; Schirmer, K.

    2010-01-01

    Due to the implementation of new legislation, such as REACh, a dramatic increase of animal use for toxicity testing is expected and the search for alternatives is timely. Cell-based in vitro assays are promising alternatives. However, the behavior of chemicals in these assays is still poorly

  6. Toxicity assessment of chemical contaminants;transition from in vitromethods to novel in vitro methods

    Directory of Open Access Journals (Sweden)

    A.A. Farshad

    2007-04-01

    Full Text Available Exposure to occupational and environmental contaminants is a major contributor to human health problems. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there areapproximately 80, 000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from ethical, economical and scientific perspectives. Therefore, increasing the number of available industrial chemicals andnew products has created a demand for alternatives to animal methods for better safety evaluation. Recent toxicity studies have demonstrated that in vitro methods are capable of rapidly providing toxicity information. In this review, current toxicity test methods for risk evaluation of industrial chemical contaminants are presented. To evaluate the potential applications of  more recent test methods developed for toxicity testing of chemical contaminants are discussed. Although  to be considered more broadly for risk assessment of human chemical exposures. In vitro methods,in vitro toxicology methods cannot exactly mimic the biodynamics of the whole body, in vitro  relationships (QSARs and physiologically based toxicokinetic (PBTK models have a potentialtest systems in combination with the knowledge of quantitative structure activity.

  7. Bioequivalence approach for whole effluent toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, R.; Wang, Q.; Fulk, F.; Deng, C.; Denton, D.

    2000-01-01

    Increased use of whole effluent toxicity (WET) tests in the regulatory arena has brought increased concern over the statistical analysis of WET test data and the determination of toxicity. One concern is the issue of statistical power. A number of WET tests may pass the current hypothesis test approach because they lack statistical power to detect relevant toxic effects because of large within-test variability. Additionally, a number of WET tests may fail the current approach because they possess excessive statistical power, as a result of small within-test variability, and detect small differences that may not be biologically relevant. The strengths and limitations of both the traditional hypothesis test approach and the bioequivalence approach for use in the National Pollutant Discharge Elimination System program were evaluated. Data from 5,213 single-concentration, short-term chronic WET tests with Ceriodaphnia dubia provided the database for analysis. Comparison of results between the current approach and the bioequivalence approach indicates that the current approach to WET testing is generally sound but that adopting the proposed bioequivalence approach resolves concerns of statistical power. Specifically, within this data set, applying the bioequivalence approach resulted in failure for tests with relatively large test variability and a pass for tests with relatively small within-test variability.

  8. Insights on in vitro models for safety and toxicity assessment of cosmetic ingredients.

    Science.gov (United States)

    Almeida, Andreia; Sarmento, Bruno; Rodrigues, Francisca

    2017-03-15

    According to the current European legislation, the safety assessment of each individual cosmetic ingredient of any formulation is the basis for the safety evaluation of a cosmetic product. Also, animal testing in the European Union is prohibited for cosmetic ingredients and products since 2004 and 2009, respectively. Additionally, the commercialization of any cosmetic products containing ingredients tested on animal models was forbidden in 2009. In consequence of these boundaries, the European Centre for the Validation of Alternative Methods (ECVAM) proposes a list of validated cell-based in vitro models for predicting the safety and toxicity of cosmetic ingredients. These models have been demonstrated as valuable and effective tools to overcome the limitations of animal in vivo studies. Although the use of in vitro cell-based models for the evaluation of absorption and permeability of cosmetic ingredients is widespread, a detailed study on the properties of these platforms and the in vitro-in vivo correlation compared with human data are required. Moreover, additional efforts must be taken to develop in vitro models to predict carcinogenicity, repeat dose toxicity and reproductive toxicity, for which no alternative in vitro methods are currently available. This review paper summarizes and characterizes the most relevant in vitro models validated by ECVAM employed to predict the safety and toxicology of cosmetic ingredients. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Implications of Animal Welfare on Toxicity Testing

    DEFF Research Database (Denmark)

    Meyer, Otto A.

    1993-01-01

    The testing strategy for chemical substances is discussed with regard to obtaining improved quality of data for health assessment while respecting the ethical responsibility for consideration of the welfare of the animals involved. Ensuring animal welfare without indulging too much...... in anthropomorphism leads to better research/testing. Current trends in toxicity testing will result in tests involving more sophisticated techniques, better quality of laboratory animals, and eventually the use of fewer animals....

  10. Toxicity of mycotoxins for the rat pulmonary macrophage in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, W.G.; Gerberick, G.F.; Lewis, D.M.; Castranova, V.

    1986-04-01

    The presence of mycotoxins in grains is well documented. Workers in grain handling occupations are commonly exposed to grain dust aerosols. Work in our laboratory has shown that T-2 toxin is highly toxic to rat alveolar macrophages in vitro, causing loss of viability, release of radiolabeled chromium, inhibition of macromolecular synthesis, inhibition of phagocytosis, and inhibition of macrophage activation. Similarly, patulin caused a significant release of radiolabeled chromium, decrease in ATP levels, significant inhibition of protein and RNA synthesis, and inhibition of phagocytosis. The data show that both T-2 toxin and patulin are highly toxic to rat alveolar macrophages in vitro. The data further suggest that the presence of these mycotoxins in airborne respirable dust might present a hazard to exposed workers.

  11. Toxicity of mycotoxins for the rat pulmonary macrophage in vitro.

    OpenAIRE

    Sorenson, W. G.; Gerberick, G F; Lewis, D M; Castranova, V.

    1986-01-01

    The presence of mycotoxins in grains is well documented. Workers in grain handling occupations are commonly exposed to grain dust aerosols. Work in our laboratory has shown that T-2 toxin is highly toxic to rat alveolar macrophages in vitro, causing loss of viability, release of radiolabeled chromium, inhibition of macromolecular synthesis, inhibition of phagocytosis, and inhibition of macrophage activation. Similarly, patulin caused a significant release of radiolabeled chromium, decrease in...

  12. Ubisol-Aqua: coenzyme Q10 prevents antiretroviral toxic neuropathy in an in vitro model.

    Science.gov (United States)

    Cherry, Catherine L; Mobarok, Masqura; Wesselingh, Steven L; Fain, Randi; Weinstock, Shelley; Tachedjian, Gilda; Srivastava, Seema; Tyssen, David P; Glass, Jonathan D; Hooker, David J

    2010-04-01

    Peripheral neuropathy is the dose-limiting toxicity of stavudine and didanosine (nucleoside analogs used in HIV treatment) and is attributed to mitochondrial toxicity from these drugs. Acetyl L-carnitine (ALC) and co-enzyme Q(10) are proposed as neuropathy treatments, but evidence to support these is limited. We examined ALC and a water-soluble formulation of co-enzyme Q(10) (H(Q)O) for the prevention of d4T and ddI neurotoxicity using cultured fetal rat DRG as an in vitro model. DdI (33microM) and d4T (50microM) caused clear toxicity (impaired neurite growth) by day 8 of DRG culture. H(Q)O at concentrations 1-100microM completely prevented the toxicity of 33microM ddI in vitro and ALC at concentrations 1-100 microM substantially (but incompletely) prevented ddI toxicity in this model. In contrast, ALC was ineffective at all concentrations tested for preventing the toxicity of 50microM d4T. H(Q)O showed dose-dependent efficacy for preventing d4T toxicity. H(Q)O (1microM) partially prevented d4T toxicity while 10 and 100microM H(Q)O completely prevented d4T toxicity in this model. We find H(Q)O is superior to ALC for preventing the neurotoxicity of d4T (the HIV treatment most associated with neuropathy) and ddI in vitro. Further study is needed to clarify any clinical role for co-enzyme Q(10) co-administration with d4T and ddI and to assess whether this compound may have a role in treating established cases of neuropathy.

  13. Animal alternatives for whole effluent toxicity testing ...

    Science.gov (United States)

    Since the 1940s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that toxicity based effluent assessments and subsequent discharge controls became globally important, when it was recognized that physical and chemical measurements alone did not protect the environment from potential impacts. Consequently, various strategies using different toxicity tests, whole effluent assessment techniques (incorporating bioaccumulation potential and persistence) plus supporting analytical tools have been developed over 30 years of practice. Numerous workshops and meetings have focused on effluent risk assessment through ASTM, SETAC, OSPAR, UK competent authorities, and EU specific country rules. Concurrent with this drive to improve effluent quality using toxicity tests, interest in reducing animal use has risen. The Health and Environmental Sciences Institute (HESI) organized and facilitated an international workshop in March 2016 to evaluate strategies for concepts, tools, and effluent assessments and update the toolbox of for effluent testing methods. The workshop objectives were to identify opportunities to use a suite of strategies for effluents, and to identify opportunities to reduce the reliance on animal tests and to determine barriers to implementation of new methodologie

  14. Mercury immune toxicity in harbour seals: links to in vitro toxicity

    Directory of Open Access Journals (Sweden)

    Mazzucchelli Gabriel

    2008-10-01

    Full Text Available Abstract Background Mercury is known to bioaccumulate and to magnify in marine mammals, which is a cause of great concern in terms of their general health. In particular, the immune system is known to be susceptible to long-term mercury exposure. The aims of the present study were (1 to determine the mercury level in the blood of free-ranging harbour seals from the North Sea and (2 to examine the link between methylmercury in vitro exposure and immune functions using seal and human mitogen-stimulated peripheral blood mononuclear cells (T-lymphocytes. Methods Total mercury was analysed in the blood of 22 harbour seals. Peripheral blood mononuclear cells were isolated from seals (n = 11 and from humans (n = 9. Stimulated lymphocytes of both species were exposed to functional tests (proliferation, metabolic activity, radioactive precursor incorporation under increasing doses of methylmercury (0.1 to 10 μM. The expression of cytokines (IL-2, IL-4 and TGF-β was investigated in seal lymphocytes by RT-PCR and by real time quantitative PCR (n = 5 at methylmercury concentrations of 0.2 and 1 μM. Finally, proteomics analysis was attempted on human lymphocytes (cytoplasmic fraction in order to identify biochemical pathways of toxicity at concentration of 1 μM (n = 3. Results The results showed that the number of seal lymphocytes, viability, metabolic activity, DNA and RNA synthesis were reduced in vitro, suggesting deleterious effects of methylmercury concentrations naturally encountered in free-ranging seals. Similar results were found for human lymphocytes. Functional tests showed that a 1 μM concentration was the critical concentration above which lymphocyte activity, proliferation and survival were compromised. The expression of IL-2 and TGF-β mRNA was weaker in exposed seal lymphocytes compared to control cells (0.2 and 1 μM. Proteomics showed some variation in the protein expression profile (e.g. vimentin. Conclusion Our results suggest that

  15. Predictive value of in vitro assays depends on the mechanism of toxicity of metal oxide nanoparticles.

    Science.gov (United States)

    Cho, Wan-Seob; Duffin, Rodger; Bradley, Mark; Megson, Ian L; MacNee, William; Lee, Jong Kwon; Jeong, Jayoung; Donaldson, Ken

    2013-10-25

    Hazard identification for risk assessment of nanoparticles (NPs) is mainly composed of in vitro cell-based assays and in vivo animal experimentation. The rapidly increasing number and functionalizations of NPs makes in vivo toxicity tests undesirable on both ethical and financial grounds, creating an urgent need for development of in vitro cell-based assays that accurately predict in vivo toxicity and facilitate safe nanotechnology. In this study, we used 9 different NPs (CeO2, TiO2, carbon black, SiO2, NiO, Co3O4, Cr2O3, CuO, and ZnO). As an in vivo toxicity endpoint, the acute lung inflammogenicity in a rat instillation model was compared with the in vitro toxicity endpoints comprising cytotoxicity, pro-inflammatory cytokine expression, or haemolytic potential. For in vitro assays, 8 different cell-based assays were used including epithelial cells, monocytic/macrophage cells, human erythrocytes, and combined culture. ZnO and CuO NPs acting via soluble toxic ions showed positive results in most of assays and were consistent with the lung inflammation data. When compared in in vitro assays at the same surface area dose (30 cm2/mL), NPs that were low solubility and therefore acting via surface reactivity had no convincing activity, except for CeO2 NP. Cytotoxicity in differentiated peripheral blood mononuclear cells was the most accurate showing 89% accuracy and 11% false negativity in predicting acute lung inflammogenicity. However, the haemolysis assay showed 100% consistency with the lung inflammation if any dose, having statistical significance was considered positivity. Other cell-based in vitro assays showed a poorer correlation with in vivo inflammogenicity. Based on the toxicity mechanisms of NPs, two different approaches can be applied for prediction of in vivo lung inflammogenicity. Most in vitro assays were good at detecting NPs that act via soluble ions (i.e., ZnO and CuO NP). However, in vitro assays were limited in detecting NPs acting via surface

  16. In vitro toxicity of formocresol, ferric sulphate, and grey MTA on human periodontal ligament fibroblasts.

    Science.gov (United States)

    Al-Haj Ali, S N; Al-Jundi, S H; Ditto, D J

    2015-02-01

    This was to assess and compare the in vitro toxicity of formocresol, ferric sulphate and MTA on cultured human periodontal ligament (PDL) fibroblasts. PDL cells were obtained from sound first permanent molars and cultured in Dulbecco's modified Eagle's medium. PDL cells were subjected to different concentrations of formocresol, ferric sulphate, and grey MTA for 24, 48, and 72 h at 37 °C. Cells that were not exposed to the tested materials served as the negative control. In vitro toxicity was assessed using MTT assay. Statistical analysis of data was accomplished using ANOVA and Tukey statistical tests (pferric sulphate>grey MTA. Only grey MTA had comparable cell viability to the negative control, the other tested materials were significantly inferior at the three exposure periods (ppulpotomy of primary teeth.

  17. Non-animal Replacements for Acute Toxicity Testing.

    Science.gov (United States)

    Barker-Treasure, Carol; Coll, Kevin; Belot, Nathalie; Longmore, Chris; Bygrave, Karl; Avey, Suzanne; Clothier, Richard

    2015-07-01

    Current approaches to predicting adverse effects in humans from acute toxic exposure to cosmetic ingredients still heavily necessitate the use of animals under EU legislation, particularly in the context of the REACH system, when cosmetic ingredients are also destined for use in other industries. These include the LD50 test, the Up-and-Down Procedure and the Fixed Dose Procedure, which are regarded as having notable scientific deficiencies and low transferability to humans. By expanding on previous in vitro tests, such as the animal cell-based 3T3 Neutral Red Uptake (NRU) assay, this project aims to develop a truly animal-free predictive test for the acute toxicity of cosmetic ingredients in humans, by using human-derived cells and a prediction model that does not rely on animal data. The project, funded by Innovate UK, will incorporate the NRU assay with human dermal fibroblasts in animal product-free culture, to generate an in vitro protocol that can be validated as an accepted replacement for the currently available in vivo tests. To date, the project has successfully completed an assessment of the robustness and reproducibility of the method, by using sodium lauryl sulphate (SLS) as a positive control, and displaying analogous results to those of the original studies with mouse 3T3 cells. Currently, the testing of five known ingredients from key groups (a surfactant, a preservative, a fragrance, a colour and an emulsifier) is under way. The testing consists of initial range-finding runs followed by three valid runs of a main experiment with the appropriate concentration ranges, to generate IC50 values. Expanded blind trials of 20 ingredients will follow. Early results indicate that this human cell-based test holds the potential to replace aspects of in vivo animal acute toxicity testing, particularly with reference to cosmetic ingredients. 2015 FRAME.

  18. In vitro assay for compounds toxic to rumen protozoa

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, A.J.; Cumming, G.J.; Graham, C.A. (ICI Australia Operations Pty. Ltd, Merrindale Research Station. Croydon, Victoria, Australia); Leng, R.A. (New England Univ., Armidale (Australia). Dept. of Biochemistry and Nutrition)

    1982-01-01

    The viability of protozoa in whole rumen fluid was assessed by measuring the incorporation of Me-/sup 14/C-choline in vitro. The use of the technique as an assay for testing antiprotozoal agents was evaluated with a variety of surfactant detergents which have previously been shown to have antiprotozoal activity in vivo. A good correlation was obtained between the potency of these compounds in vitro and in vivo.

  19. Neurotoxicity testing: a discussion of in vitro alternatives.

    Science.gov (United States)

    Costa, L G

    1998-04-01

    A large number of chemicals may exert adverse effects on the central and/or peripheral nervous system. A commonly recommended strategy for neurotoxicity testing is that of a tiered approach aimed at identifying and characterizing the neurotoxicity of a compound. Guidelines exist in the United States and other countries that define the tests to be utilized in tier 1 testing. To address problems related to the increasing cost and time required for toxicity testing, the increasing number of chemicals being developed, and the concern of animal welfare activists, attention is currently being devoted to in vitro alternatives. This paper addresses the use of in vitro systems in neurotoxicology, and their potential role in a general strategy for neurotoxicity testing. The advantages and disadvantages of in vitro approaches for mechanistic studies and for screening of neurotoxicants are discussed. Suggestions for further validation studies are proposed.

  20. In vitro Toxicity of Fungicides of Different Mode of Action to Agaricus bisporus (Lange Imbach

    Directory of Open Access Journals (Sweden)

    Ivana Potočnik

    2009-01-01

    Full Text Available Isolates of Agaricus bisporus strains F56 and U3 were tested for sensitivity to several selected fungicides in vitro. The analysis showed that flusilasole + carbendazim and cyproconazole + carbendazim were the most toxic fungicides to A. bisporus strain F56 with respective EC50 values of 0.04 and 0.23 mg/l. The least toxic fungicides were carbendazim (EC50 = 16.58 mg/l and trifloxystrobin (EC50 = 20.69 mg/l to A. bisporus F56 and benomyl (EC50 = 14.99 mg/l to A. bisporus U3.

  1. Predictive value of in vitro assays depends on the mechanism of toxicity of metal oxide nanoparticles

    National Research Council Canada - National Science Library

    Cho, Wan-Seob; Duffin, Rodger; Bradley, Mark; Megson, Ian L; MacNee, William; Lee, Jong Kwon; Jeong, Jayoung; Donaldson, Ken

    2013-01-01

    ...). As an in vivo toxicity endpoint, the acute lung inflammogenicity in a rat instillation model was compared with the in vitro toxicity endpoints comprising cytotoxicity, pro-inflammatory cytokine...

  2. Advancing In Vitro-In Vivo Extrapolations of Mechanism-Specific Toxicity Data Through Toxicokinetic Modeling.

    Science.gov (United States)

    Brinkmann, Markus; Preuss, Thomas G; Hollert, Henner

    International legislation, such as the European REACH regulation (registration, evaluation, authorization, and restriction of chemicals), mandates the assessment of potential risks of an ever-growing number of chemicals to the environment and human health. Although this legislation is considered one of the most important investments in consumer safety ever, the downside is that the current testing strategies within REACH rely on extensive animal testing. To address the ethical conflicts arising from these increased testing requirements, decision-makers, such as the European Chemicals Agency (ECHA), are committed to Russel and Burch's 3R principle (i.e., reduction, replacement, refinement) by demanding that animal experiments should be substituted with appropriate alternatives whenever possible. A potential solution of this dilemma might be the application of in vitro bioassays to estimate toxic effects using cells or cellular components instead of whole organisms. Although such assays are particularly useful to assess potential mechanisms of toxic action, scientists require appropriate methods to extrapolate results from the in vitro level to the situation in vivo. Toxicokinetic models are a straightforward means of bridging this gap. The present chapter describes different available options for in vitro-in vivo extrapolation (IVIVE) of mechanism-specific effects focused on fish species and also reviews the implications of confounding factors during the conduction of in vitro bioassays and their influence on the optimal choice of different dose metrics.

  3. Digital holographic microscopy as multimodal read out for in vitro nanomaterial cytotoxicity testing

    Science.gov (United States)

    Mues, Sarah; Ketelhut, Steffi; Kemper, Björn; Schnekenburger, Jürgen

    2017-07-01

    Digital holographic microscopy (DHM) was used as multimodal optical method for nanomaterial toxicity testing that overcomes the limitations and assay disturbances of conventional in vitro assays based on absorbance or fluorescence read outs.

  4. Toxicity of Uranium Adsorbent Materials using the Microtox Toxicity Test

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jiyeon [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jeters, Robert T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, Gary A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bonheyo, George T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-01

    The Marine Sciences Laboratory at the Pacific Northwest National Laboratory evaluated the toxicity of a diverse range of natural and synthetic materials used to extract uranium from seawater. The uranium adsorbent materials are being developed as part of the U. S. Department of Energy, Office of Nuclear Energy, Fuel Resources Program. The goal of this effort was to identify whether deployment of a farm of these materials into the marine environment would have any toxic effects on marine organisms.

  5. A combined in vitro approach to improve the prediction of mitochondrial toxicants.

    Science.gov (United States)

    Eakins, Julie; Bauch, Caroline; Woodhouse, Heather; Park, Benjamin; Bevan, Samantha; Dilworth, Clive; Walker, Paul

    2016-08-01

    Drug induced mitochondrial dysfunction has been implicated in organ toxicity and the withdrawal of drugs or black box warnings limiting their use. The development of highly specific and sensitive in vitro assays in early drug development would assist in detecting compounds which affect mitochondrial function. Here we report the combination of two in vitro assays for the detection of drug induced mitochondrial toxicity. The first assay measures cytotoxicity after 24h incubation of test compound in either glucose or galactose conditioned media (Glu/Gal assay). Compounds with a greater than 3-fold toxicity in galactose media compared to glucose media imply mitochondrial toxicity. The second assay measures mitochondrial respiration, glycolysis and a reserve capacity with mechanistic responses observed within one hour following exposure to test compound. In order to assess these assays a total of 72 known drugs and chemicals were used. Dose-response data was normalised to 100× Cmax giving a specificity, sensitivity and accuracy of 100%, 81% and 92% respectively for this combined approach. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. In vitro assessment of the toxicity of bushfire emissions: A review.

    Science.gov (United States)

    Dong, Trang T T; Hinwood, Andrea L; Callan, Anna C; Zosky, Graeme; Stock, William D

    2017-12-15

    Bushfires produce many toxic pollutants and the smoke has been shown to have negative effects on human health, especially to the respiratory system. Bushfires are predicted to increase in size and frequency, leading to a greater incidence of smoke and impacts. While there are many epidemiological studies of the potential impact on populations, there are few studies using in vitro methods to investigate the biological effects of bushfire emissions to better understand its toxicity and significance. This review focused on the literature pertaining to in vitro toxicity testing to determine the state of knowledge on current methods and findings on the impacts of bushfire smoke. There was a considerable variation in the experimental conditions, outcomes and test concentrations used by researchers using in vitro methods. Of the studies reviewed, most reported adverse impacts of particulate matter (PM) on cytotoxic and genotoxic responses. Studies on whole smoke were rare. Finer primary particulates from bushfire smoke were generally found to be more toxic than the coarse particulates and the toxicological endpoints of bushfire PM different to ambient PM. However the variation in study designs and experimental conditions made comparisons difficult. This review highlights the need for standard protocols to enable appropriate comparisons between studies to be undertaken including the assessment of physiologically relevant outcomes. Further work is essential to establish the effect of burning different vegetation types and combustion conditions on the toxicity of bushfire emissions to better inform both health and response agencies on the significance of smoke from bushfires. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. SEDIMENT TOXICITY ASSESSMENT: COMPARISON OF STANDARD AND NEW TESTING DESIGNS

    Science.gov (United States)

    Standard methods of sediment toxicity testing are fairly well accepted; however, as with all else, evolution of these methods is inevitable. We compared a standard ASTM 10-day amphipod toxicity testing method with smaller, 48- and 96-h test methods using very toxic and reference ...

  8. In vitro toxicity of trichothecenes on rat haematopoietic progenitors.

    Science.gov (United States)

    Parent-Massin, D; Thouvenot, D

    1995-01-01

    The fusarial toxicosis induced by trichothecenes is characterized by common syndromes such as vomiting, inflammation, haemorrhages, diarrhoea and haematological changes. Subchronic ingestion of trichothecenes causes a decrease in circulating white cells. This leukopenic change of animals is reported as a characteristic feature in the best known human disorder: Alimentary Toxic Aleukia (ATA). The aim of the present study was to evaluate whether the haematologic disorders imputed to trichothecenes were a result of myelotoxicity by investigating in an in vitro model. Rat haematopoietic progenitors, Colony Forming Units-Granulocytes and Macrophages (CFU-GM), were cultured in the presence of several concentrations of four trichothecenes; T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and deoxynivalenol (DON). All these trichothecenes were cytotoxic to rat haematopoietic progenitor cells. It is concluded that haematological disorders observed during trichothecene intoxication of animals are caused by the destruction of haematopoietic progenitors such as CFU-GM cells.

  9. In vitro toxicity of zinc oxide nanoparticles: a review

    Energy Technology Data Exchange (ETDEWEB)

    Pandurangan, Muthuraman; Kim, Doo Hwan, E-mail: frenzram1980@gmail.com [Konkuk University, Department of Bioresources and Food Sciences (Korea, Republic of)

    2015-03-15

    The toxic effect of ZnO nanoparticles is due to their solubility. ZnO nanoparticles dissolve in the extracellular region, which in turn increases the intracellular [Zn{sup 2+}] level. The mechanism for increased intracellular [Zn{sup 2+}] level and ZnO nanoparticles dissolution in the medium is still unclear. Cytotoxicity, increased oxidative stress, increased intracellular [Ca{sup 2+}] level, decreased mitochondrial membrane potential, and interleukin-8 productions occur in the BEAS-2B bronchial epithelial cells and A549 alveolar adenocarcinoma cells following the exposure of ZnO nanoparticles. Confluent C2C12 cells are more resistant to ZnO nanoparticles compared to the sparse monolayer. Loss of 3T3-L1 cell viability, membrane leakage, and morphological changes occurs due to exposure of ZnO nanoparticles. ZnO nanoparticle induces cytotoxicity and mitochondrial dysfunction in RKO colon carcinoma cells. The occurrence of apoptosis, increased ROS level, reduced mitochondrial activity and formation of tubular intracellular structures are reported following exposure of ZnO nanoparticles in skin cells. Macrophages, monocytes, and dendritic cells are affected by ZnO nanoparticles. In addition, genotoxicity is also induced. The present review summarizes the literature on in vitro toxicity of ZnO nanoparticles (10–100 nm) on various cell lines.

  10. In vitro and in vivo toxicity assessment of nanoparticles

    Science.gov (United States)

    Kumar, Vinay; Sharma, Neha; Maitra, S. S.

    2017-11-01

    Nanotechnology has revolutionized gene therapy, diagnostics and environmental remediation. Their bulk production, uses and disposal have posed threat to the environment. With the appearance of these nanoparticles in the environment, their toxicity assessment is an immediate concern. This review is an attempt to summarize the major techniques used in cytotoxity determination. The review also presents a detailed and elaborative discussion on the toxicity imposed by different types of nanoparticles including carbon nanotubes, gold nanoparticles, silver nanoparticles, quantum dots, fullerenes, aluminium nanoparticles, zinc nanoparticles, iron nanoparticles, titanium nanoparticles and silica nanoparticles. It discusses the in vitro and in vivo toxological effects of nanoparticles on bacteria, microalgae, zebrafish, crustacean, fish, rat, mouse, pig, guinea pig, human cell lines and human. It also discusses toxological effects on organs such as liver, kidney, spleen, sperm, neural tissues, liver lysosomes, spleen macrophages, glioblastoma cells, hematoma cells and various mammalian cell lines. It provides information about the effects of nanoparticles on the gene-expression, growth and reproduction of the organisms.

  11. Current and future needs for developmental toxicity testing.

    Science.gov (United States)

    Makris, Susan L; Kim, James H; Ellis, Amy; Faber, Willem; Harrouk, Wafa; Lewis, Joseph M; Paule, Merle G; Seed, Jennifer; Tassinari, Melissa; Tyl, Rochelle

    2011-10-01

    A review is presented of the use of developmental toxicity testing in the United States and international regulatory assessment of human health risks associated with exposures to pharmaceuticals (human and veterinary), chemicals (agricultural, industrial, and environmental), food additives, cosmetics, and consumer products. Developmental toxicology data are used for prioritization and screening of pharmaceuticals and chemicals, for evaluating and labeling of pharmaceuticals, and for characterizing hazards and risk of exposures to industrial and environmental chemicals. The in vivo study designs utilized in hazard characterization and dose-response assessment for developmental outcomes have not changed substantially over the past 30 years and have served the process well. Now there are opportunities to incorporate new technologies and approaches to testing into the existing assessment paradigm, or to apply innovative approaches to various aspects of risk assessment. Developmental toxicology testing can be enhanced by the refinement or replacement of traditional in vivo protocols, including through the use of in vitro assays, studies conducted in alternative nonmammalian species, the application of new technologies, and the use of in silico models. Potential benefits to the current regulatory process include the ability to screen large numbers of chemicals quickly, with the commitment of fewer resources than traditional toxicology studies, and to refine the risk assessment process through an enhanced understanding of the mechanisms of developmental toxicity and their relevance to potential human risk. As the testing paradigm evolves, the ability to use developmental toxicology data to meet diverse critical regulatory needs must be retained. © 2011 Wiley Periodicals, Inc.

  12. Acute toxicity of five pesticides to Apis mellifera larvae reared in vitro.

    Science.gov (United States)

    Dai, Pingli; Jack, Cameron J; Mortensen, Ashley N; Ellis, James D

    2017-11-01

    The reported high loss rates of managed honey bee colonies have been attributed to diverse stressors including pesticides. Honey bee larvae can be exposed to pesticides in contaminated nectar, pollen and wax. Due to the difficulties of rearing larvae in vitro, research focusing on adult bee exposure to pesticides is more common than that on larva exposure to pesticides. Herein, we aimed to assess the acute toxicity of five insecticides to honey bee larvae using an improved in vitro rearing method. LC 50 and LD 50 were calculated for larvae at 72 h following a single diet exposure administered when the larvae were 84 ± 12 h old. Solvent control larval mortalities were less than 15% at 72 h. The LC 50 values (mg L -1 ) for each tested pesticide were as follows: amitraz, 494.27; chlorpyrifos, 15.39; coumaphos, 90.01; fluvalinate, 27.69; and imidacloprid, 138.84. The LD 50 values in µg per larva were 14.83 (amitraz), 0.46 (chlorpyrifos), 2.70 (coumaphos), 0.83 (fluvalinate) and 4.17 (imidacloprid). The toxicity of the test pesticides to honey bee larvae from most to least toxic was chlorpyrifos > fluvalinate > coumaphos = imidacloprid > amitraz. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Toxicity testing using microcosms. Chapter 13

    Energy Technology Data Exchange (ETDEWEB)

    Sheppard, S.C

    1996-07-01

    Microcosms are, literally, small worlds, and there are very nearly as many interpretations of what that means as there are researchers willing to use them. There is a lively debate on what constitutes a microcosm, and if there are any advantages to be gained over single-species ecotoxicological investigations (Cairns, 1983). As a result, few microcosm toxicity tests have any form of official sanction (van Gestel and van Straalen, 1994), and no soil microcosm tests are in widespread, routine usage. The American Society for Testing and Materials (ASTM) does list one soil microcosm methodology (E 1197-87, ASTM, 1987). As Golley (1985) comments, there are 4 or 5 million species of organisms on earth, and they each live in communities of 1000 to 2000 species with substantial ecological interconnections. We cannot build systems as complex, and yet we must study impacts on such systems. Microcosms offer an additional step on the way from studies of single species toward studies of true ecological complexity. (author)

  14. Prediction of liver toxicity and mode of action using metabolomics in vitro in HepG2 cells.

    Science.gov (United States)

    Ramirez, Tzutzuy; Strigun, Alexander; Verlohner, Andreas; Huener, Hans-Albrecht; Peter, Erik; Herold, Michael; Bordag, Natalie; Mellert, Werner; Walk, Tilmann; Spitzer, Michael; Jiang, Xiaoqi; Sperber, Saskia; Hofmann, Thomas; Hartung, Thomas; Kamp, Hennicke; van Ravenzwaay, Ben

    2017-09-30

    Liver toxicity is a leading systemic toxicity of drugs and chemicals demanding more human-relevant, high throughput, cost effective in vitro solutions. In addition to contributing to animal welfare, in vitro techniques facilitate exploring and understanding the molecular mechanisms underlying toxicity. New 'omics technologies can provide comprehensive information on the toxicological mode of action of compounds, as well as quantitative information about the multi-parametric metabolic response of cellular systems in normal and patho-physiological conditions. Here, we combined mass-spectroscopy metabolomics with an in vitro liver toxicity model. Metabolite profiles of HepG2 cells treated with 35 test substances resulted in 1114 cell supernatants and 3556 intracellular samples analyzed by metabolomics. Control samples showed relative standard deviations of about 10-15%, while the technical replicates were at 5-10%. Importantly, this procedure revealed concentration-response effects and patterns of metabolome changes that are consistent for different liver toxicity mechanisms (liver enzyme induction/inhibition, liver toxicity and peroxisome proliferation). Our findings provide evidence that identifying organ toxicity can be achieved in a robust, reliable, human-relevant system, representing a non-animal alternative for systemic toxicology.

  15. In vitro and human testing strategies for skin irritation.

    Science.gov (United States)

    Robinson, M K; Osborne, R; Perkins, M A

    2000-01-01

    Prior to the manufacture, transport, and marketing of chemicals or products, it is critical to assess their potential for skin toxicity (corrosion or irritation), thereby protecting the worker and consumer from adverse skin effects due to intended or accidental skin exposure. Traditionally, animal testing procedures have provided the data needed to assess the more severe forms of skin toxicity, and current regulations may require animal test data before permission can be obtained to manufacture, transport, or market chemicals or the products that contain them. In recent years, the use of animals to assess skin safety has been opposed by some as inhumane and unnecessary. The conflicting needs of the industrial toxicologist to (1) protect human safety, (2) comply with regulations, and (3) reduce animal testing have led to major efforts to develop alternative, yet predictive, test methods. A variety of in vitro skin corrosion test methods have been developed and several have successfully passed initial international validation. These have included skin or epidermal equivalent assays that have been shown to distinguish corrosive from noncorrosive chemicals. These skin/epidermal equivalent assays have also been modified and used to assess skin irritation potential relative to existing human exposure test data. The data show a good correlation between in vitro assay data and different types of human skin irritation data for both chemicals and consumer products. The effort to eliminate animal tests has also led to the development of a novel human patch test for assessment of acute skin irritation potential. A case study shows the benefits of in vitro and human skin irritation tests compared to the animal tests they seek to replace, and strategies now exist to adequately assess human skin irritation potential without the need to rely on animal test methods.

  16. Toward in vitro biomarkers for developmental toxicity and their extrapolation to the in vivo situation.

    Science.gov (United States)

    Louisse, Jochem; Verwei, Miriam; Woutersen, Ruud A; Blaauboer, Bas J; Rietjens, Ivonne M C M

    2012-01-01

    Reliable in vitro and in silico assays as alternatives for in vivo developmental toxicity studies are urgently needed, for the replacement, reduction and refinement (3Rs) of animal use in toxicological research. Therefore, relevant biomarkers for in vivo developmental toxicity in in vitro assays are needed. The present review gives an overview of alternative assays, as described in literature, for in vivo developmental toxicity, including the effects (readouts) assessed in these assays. The authors discuss how these data may be used to obtain relevant biomarkers for in vivo developmental toxicity, and how in vitro effect data can be translated to the in vivo situation using physiologically based kinetic (PBK) modeling. Relevance of readouts in in vitro developmental toxicity assays as predictive biomarkers for in vivo developmental toxicity should be evaluated by comparing the obtained in vitro effect concentrations with in vivo internal concentrations at dose levels causing developmental toxicity. Extrapolation of the in vitro effect concentrations to in vivo dose levels using PBK modeling (i.e., reverse dosimetry) is promising in its use to derive points of departure for risk assessment, enabling the use of in vitro toxicity data in the safety assessment of compounds.

  17. Use of physiologically based kinetic modeling-facilitated reverse dosimetry of in vitro toxicity data for prediction of in vivo developmental toxicity of tebuconazole in rats.

    Science.gov (United States)

    Li, Hequn; Zhang, Mengying; Vervoort, Jacques; Rietjens, Ivonne M C M; van Ravenzwaay, Bennard; Louisse, Jochem

    2017-01-15

    Toxicological hazard and risk assessment largely rely on animal testing. For economic and ethical reasons, the development and validation of reliable alternative methods for these animal studies, such as in vitro assays, are urgently needed. In vitro concentration-response curves, however, need to be translated into in vivo dose-response curves for risk assessment purposes. In the present study, we translated in vitro concentration-response data of the antifungal compound tebuconazole, obtained in the ES-D3 cell differentiation assay, into predicted in vivo dose-response data for developmental toxicity using physiologically based kinetic (PBK) modeling-facilitated reverse dosimetry. Using the predicted in vivo dose-response data BMD(L)10 values for developmental toxicity in rat were calculated and compared with NOAEL values for developmental toxicity data in rats as reported in the literature. The results show that the BMDL10 value from predicted dose-response data are a reasonable approximation of the NOAEL values (ca. 3-fold difference). It is concluded that PBK modeling-facilitated reverse dosimetry of in vitro toxicity data is a promising tool to predict in vivo dose-response curves and may have the potential to define a point of departure for deriving safe exposure limits in risk assessment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Pulmonary toxicity of nanomaterials: a critical comparison of published in vitro assays and in vivo inhalation or instillation studies.

    Science.gov (United States)

    Landsiedel, Robert; Sauer, Ursula G; Ma-Hock, Lan; Schnekenburger, Jürgen; Wiemann, Martin

    2014-11-01

    To date, guidance on how to incorporate in vitro assays into integrated approaches for testing and assessment of nanomaterials is unavailable. In addressing this shortage, this review compares data from in vitro studies to results from in vivo inhalation or intratracheal instillation studies. Globular nanomaterials (ion-shedding silver and zinc oxide, poorly soluble titanium dioxide and cerium dioxide, and partly soluble amorphous silicon dioxide) and nanomaterials with higher aspect ratios (multiwalled carbon nanotubes) were assessed focusing on the Organisation for Economic Co-Operation and Development (OECD) reference nanomaterials for these substances. If in vitro assays are performed with dosages that reflect effective in vivo dosages, the mechanisms of nanomaterial toxicity can be assessed. In early tiers of integrated approaches for testing and assessment, knowledge on mechanisms of toxicity serves to group nanomaterials thereby reducing the need for animal testing.

  19. [Toxicity evaluation of sewage treatment plant effluent of chemical industrial park along the Yangtze River on rat testicular germ cells in vitro].

    Science.gov (United States)

    Hu, Guan-Jiu; Wang, Xiao-Yi; Shi, Wei; Bai, Chou-Yong; Wu, Jiang; Liu, Hong-Ling; Yu, Hong-Xia

    2009-05-15

    By using rat testicular germ cells in vitro toxicity testing method based on original cells culture, the reproduction toxicity of sewage treatment plant effluent of Chemical Industrial Park along the Yangtze River was evaluated, through cells changes in morphologic, activity and viability parameters. The results showed that both of the effluents from new developed Chemical Industrial Park A and provincial Chemical Industrial Park B contain reproductive toxic substances. The toxicity of Park A has more significant undergone changes in cells activity of sertoli cells (p Park B. Sepermatogenic cells are more sensitive in indicating reproduction toxicity for testicular, compared with leyding cells and sertoli cells. This study demonstrated that, as an indispensable and complementary tool for water quality assessment, rat testicular germ cells in vitro toxicity testing based on original cells culture can be used to comprehensively evaluate the reproduction toxicity of sewage treatment plant effluent, and provide prompt and useful discharge quality information.

  20. 78 FR 69414 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2013-11-19

    ... AGENCY Toxic Substances Control Act Chemical Testing; Receipt of Test Data AGENCY: Environmental... test rule issued by EPA under the Toxic Substances Control Act (TSCA). The purpose of this notice is to... pigments; Toxicity to Algae; Acute emulsion polymerization in Inhalation Toxicity in paper, textile, fiber...

  1. Alternative testing strategies for predicting developmental toxicity of antifungal compound

    NARCIS (Netherlands)

    Li, H.

    2016-01-01

    Determination of safe human exposure levels of chemicals in toxicological risk assessments largely relies on animal toxicity data. In these toxicity studies, the highest number of animals are used for reproductive and developmental toxicity testing. Because of economic and ethical reasons, there is

  2. Evaluation of Toxicity Ranking for Metal Oxide Nanoparticles via an in Vitro Dosimetry Model.

    Science.gov (United States)

    Liu, Rong; Liu, Haoyang Haven; Ji, Zhaoxia; Chang, Chong Hyun; Xia, Tian; Nel, Andre E; Cohen, Yoram

    2015-09-22

    It has been argued that in vitro toxicity testing of engineered nanoparticles (NPs) should consider delivered dose (i.e., NP mass settled per suspension volume) rather than relying exclusively on administered dose (initial NP mass concentration). Delivered dose calculations require quantification of NP sedimentation in tissue cell culture media, taking into consideration fundamental suspension properties. In this article, we calculate delivered dose using a first-principles "particles in a box" sedimentation model, which accounts for the particle size distribution, fractal dimension, and permeability of agglomerated NPs. The sedimentation model was evaluated against external and our own experimental sedimentation data for metal oxide NPs. We then utilized the model to construct delivered dose-response analysis for a library of metal oxide NPs (previously used for hazard ranking and prediction making) in different cell culture media. Hierarchical hazard ranking of the seven (out of 24) toxic metal oxide NPs in our library, using EC50 calculated on the basis of delivered dose, did not measurably differ from our ranking based on administered dose. In contrast, simplified sedimentation calculations based on the assumption of impermeable NP agglomerates of a single average size significantly underestimated the settled NPs' mass, resulting in misinterpretation of toxicity ranking. It is acknowledged that in vitro dose-response outcomes are likely to be shaped by complex toxicodynamics, which include NP/cellular association, triggering of dynamic cell response pathways involved in NP uptake, and multiple physicochemical parameters that influence NP sedimentation and internalization.

  3. Non-animal methodologies within biomedical research and toxicity testing.

    Science.gov (United States)

    Knight, Andrew

    2008-01-01

    Laboratory animal models are limited by scientific constraints on human applicability, and increasing regulatory restrictions, driven by social concerns. Reliance on laboratory animals also incurs marked - and in some cases, prohibitive - logistical challenges, within high-throughput chemical testing programmes, such as those currently underway within Europe and the US. However, a range of non-animal methodologies is available within biomedical research and toxicity testing. These include: mechanisms to enhance the sharing and assessment of existing data prior to conducting further studies, and physicochemical evaluation and computerised modelling, including the use of structure-activity relationships and expert systems. Minimally-sentient animals from lower phylogenetic orders or early developmental vertebral stages may be used, as well as microorganisms and higher plants. A variety of tissue cultures, including immortalised cell lines, embryonic and adult stem cells, and organotypic cultures, are also available. In vitro assays utilising bacterial, yeast, protozoal, mammalian or human cell cultures exist for a wide range of toxic and other endpoints. These may be static or perfused, and may be used individually, or combined within test batteries. Human hepatocyte cultures and metabolic activation systems offer potential assessment of metabolite activity and organ-organ interaction. Microarray technology may allow genetic expression profiling, increasing the speed of toxin detection, well prior to more invasive endpoints. Enhanced human clinical trials utilising micro- dosing, staggered dosing, and more representative study populations and durations, as well as surrogate human tissues, advanced imaging modalities and human epidemiological, sociological and psycho- logical studies, may increase our understanding of illness aetiology and pathogenesis, and facilitate the development of safe and effective pharmacologic interventions. Particularly when human tissues

  4. In vitro toxicity of propolis in comparison with other primary teeth pulpotomy agents on human fibroblasts.

    Science.gov (United States)

    Al-Haj Ali, Sanaa Najeh

    2016-08-01

    The aim of this study was to assess and compare the in vitro toxicity of propolis with other primary teeth pulpotomy medicaments. Human periodontal ligament (PDL) cells were subjected to different concentrations of propolis, formocresol, ferric sulfate, and gray mineral trioxide aggregate (MTA) (0.05, 0.5, 5, 50, and 100 μg/mL) for 24 h at 37°C. Cells that were not exposed to the tested materials served as the negative control. In vitro toxicity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Statistical analysis of the data was accomplished using anova and Tukey statistical tests (P propolis and gray MTA had comparable cell viability to the negative control group. Almost all remaining concentrations of tested materials were significantly inferior to the negative control after 24 h of exposure (P Propolis and MTA are more biocompatible than formocresol and ferric sulfate since they were both able to preserve PDL fibroblasts for up to 24 h. © 2015 Wiley Publishing Asia Pty Ltd.

  5. Bacterial and enzymatic bioassays for toxicity testing in the environment.

    Science.gov (United States)

    Bitton, G; Koopman, B

    1992-01-01

    Microbioassays using bacteria or enzymes are increasingly applied to measure chemical toxicity in the environment. Attractive features of these assays may include low cost, rapid response to toxicants, high sample throughput, modest laboratory equipment and space requirements, low sample volume, portability, and reproducible responses. Enzymatic tests rely on measurement of either enzyme activity or enzyme biosynthesis. Dehydrogenases are the enzymes most used in toxicity testing. Assay of dehydrogenase activity is conveniently carried out using oxidoreduction dyes such as tetrazolium salts. Other enzyme activity tests utilize ATPases, esterases, phosphatases, urease, luciferase, beta-galactosidase, protease, amylase, or beta-glucosidase. Recently, the inhibition of enzyme (beta-galactosidase, tryptophanase, alpha-glucosidase) biosynthesis has been explored as a basis for toxicity testing. Enzyme biosynthesis was found to be generally more sensitive to organic chemicals than enzyme activity. Bacterial toxicity tests are based on bioluminescence, motility, growth, viability, ATP, oxygen uptake, nitrification, or heat production. An important aspect of bacterial tests is the permeability of cells to environmental toxicants, particularly organic chemicals of hydrophobic nature. Physical, chemical, and genetic alterations of the outer membrane of E. coli have been found to affect test sensitivity to organic toxicants. Several microbioassays are now commercially available. The names of the assays and their basis are: Microtox (bioluminescence), Polytox (respiration), ECHA Biocide Monitor (dehydrogenase activity), Toxi-Chromotest (enzyme biosynthesis), and MetPAD (enzyme activity). An important feature common to these tests is the provision of standardized cultures of bacteria in freeze-dried form. Two of the more recent applications of microbioassays are in sediment toxicity testing and toxicity reduction evaluation. Sediment pore water may be assayed directly or

  6. Status and applications of echinoid (phylum echinodermata) toxicity test methods

    Energy Technology Data Exchange (ETDEWEB)

    Bay, S.; Burgess, R.; Nacci, D.

    1993-01-01

    The use of echinoderms for toxicity testing has focused primarily on sea urchins and sand dollars (Strongylocentrotus purpuratus, Arbacia punctulata, Lytechinus pictus, and Dendraster excentricus, for example). The status and relative sensitivity of various test methods are described. The most frequently used test methods consist of short-term exposures of sea urchin sperm or embryos; these tests can be easily conducted at all times of the year by using species with complementary spawning cycles or laboratory conditioned populations of a single species. Data from reference toxicant and effluent toxicity tests are summarized. Information on the precision and sensitivity of echinoid test methods are limited and preclude rigorous comparisons with other test methods. The available data indicate that the sensitivity and precision of these methods are comparable to short-term chronic methods for other marine invertebrates and fish. Recent application of the sperm test in toxicity identification evaluations (TIEs) and studies of effluent toxicity decay and sediment toxicity illustrate the versatility of this rapid (10 to 60 min exposure) test method. Embryo tests typically use a 48 to 96 h exposure period and measure the occurrence of embryo malformations. Most recent applications of the embryo test have been for the assessment of sediment elutriate toxicity. Adult echinoderms are not frequently used to assess effluent or receiving water toxicity. Recent studies have had success in using the adult life stage of urchins and sand dollars to assess the effects of contaminated sediment on growth, behavior, and bioaccumulation.

  7. An in vitro Method for Predicting Inhalation Toxicity of Impregnation Spray Products

    DEFF Research Database (Denmark)

    Sørli, Jorid B.; Hansen, Jitka S.; Nørgaard, Asger Wisti

    2015-01-01

    Impregnation spray products are used for making surfaces water and dirt repellent. The products are composed of one or more active film-forming components dissolved or suspended in an appropriate solvent mixture. Exposure to impregnation spray products may cause respiratory distress and new cases...... of the inhalation toxicity of impregnation spray products and thus may reduce the need for animal testing....... of this study was to evaluate whether disruption of the pulmonary surfactant film can be used as a predictor of the toxic effects in vivo. Nine impregnation products with various chemical compositions were selected for testing and the main constituents of each product, e.g., solvents, co-solvents and film...... and in vivo. The true positive rate of the in vitro method was 100%, i.e. the test could correctly identify all products with toxic effects in vivo, the true negative rate was 40%. Investigation of inhibition of the pulmonary surfactant system, e.g. by capillary surfactometry, was found useful for evaluation...

  8. Synergistic effects of fumonisin B1 and ochratoxin A: are in vitro cytotoxicity data predictive of in vivo acute toxicity?

    Science.gov (United States)

    Creppy, Edmond E; Chiarappa, Patrizia; Baudrimont, Isabelle; Borracci, Pietro; Moukha, Serge; Carratù, Maria R

    2004-09-01

    Contamination of food and feeds by mycotoxins is a major problem of human and animals health concern which is also extremely detrimental to economy. Mycotoxins producing moulds may produce a diversity of toxins such as aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, tremorgenic toxins and ergot alkaloids. Although toxicological, environmental and epidemiological studies have addressed the problem of these toxins one by one, more than one mycotoxin are found usually in the same contaminated commodities. That rises the incommensurable problem of multi-toxicosis in which the respective metabolites are also involved. These mycotoxins bear potential toxicity leading to acute and chronic effects in humans and animals, depending on species. The mechanisms that lead to toxic effects, such as immune toxicity, and carcinogenicity are complexe. The risk assessment for humans potentially exposed to multi-mycotoxins suffers very much from the lack of adequate food consumption data. Furthermore, for a given mycotoxin synergism and antagonism with other mycotoxins found in the same food commodities are not taken into account. The case of combination of ochratoxin A (OTA) and fumonisin B1 (FB1) has been addressed in the present paper with the purpose of predicting the in vivo toxicity using a simple in vitro test, i.e. neutral red uptake, in three different cell-lines, C6 glioma cells, Caco-2 cells and Vero cells. Using the equation of [ATLA 27 (1999) 957], in vivo toxicity (LD50) is in adequation with the in vitro data, (IC50 values) for both toxins as well as for the combination of 10 microM OTA and variable concentrations of FB1 (10-50 microM). A synergistic effect is prouved in vitro that is in line with some in vivo data from the literature. Such simple in vitro test may thus help predicting in vivo toxicity of combinations of mycotoxins naturally occurring in foodstuffs.

  9. The use of in vitro toxicity data and physiologically based kinetic modeling to predict dose-response curves for in vivo developmental toxicity of glycol ethers in rat and man.

    Science.gov (United States)

    Louisse, Jochem; de Jong, Esther; van de Sandt, Johannes J M; Blaauboer, Bas J; Woutersen, Ruud A; Piersma, Aldert H; Rietjens, Ivonne M C M; Verwei, Miriam

    2010-12-01

    At present, regulatory assessment of systemic toxicity is almost solely carried out using animal models. The European Commission's REACH legislation stimulates the use of animal-free approaches to obtain information on the toxicity of chemicals. In vitro toxicity tests provide in vitro concentration-response curves for specific target cells, whereas in vivo dose-response curves are regularly used for human risk assessment. The present study shows an approach to predict in vivo dose-response curves for developmental toxicity by combining in vitro toxicity data and in silico kinetic modeling. A physiologically based kinetic (PBK) model was developed, describing the kinetics of four glycol ethers and their embryotoxic alkoxyacetic acid metabolites in rat and man. In vitro toxicity data of these metabolites derived in the embryonic stem cell test were used as input in the PBK model to extrapolate in vitro concentration-response curves to predicted in vivo dose-response curves for developmental toxicity of the parent glycol ethers in rat and man. The predicted dose-response curves for rat were found to be in concordance with the embryotoxic dose levels measured in reported in vivo rat studies. Therefore, predicted dose-response curves for rat could be used to set a point of departure for deriving safe exposure limits in human risk assessment. Combining the in vitro toxicity data with a human PBK model allows the prediction of dose-response curves for human developmental toxicity. This approach could therefore provide a means to reduce the need for animal testing in human risk assessment practices.

  10. Prediction of Chemical Carcinogenicity in Rodents from in vitro Genetic Toxicity Assays

    Science.gov (United States)

    Tennant, Raymond W.; Margolin, Barry H.; Shelby, Michael D.; Zeiger, Errol; Haseman, Joseph K.; Spalding, Judson; Caspary, William; Resnick, Michael; Stasiewicz, Stanley; Anderson, Beth; Minor, Robert

    1987-05-01

    Four widely used in vitro assays for genetic toxicity were evaluated for their ability to predict the carcinogenicity of selected chemicals in rodents. These assays were mutagenesis in Salmonella and mouse lymphoma cells and chromosome aberrations and sister chromatid exchanges in Chinese hamster ovary cells. Seventy-three chemicals recently tested in 2-year carcinogenicity studies conducted by the National Cancer Institute and the National Toxicology Program were used in this evaluation. Test results from the four in vitro assays did not show significant differences in individual concordance with the rodent carcinogenicity results; the concordance of each assay was approximately 60 percent. Within the limits of this study there was no evidence of complementarity among the four assays, and no battery of tests constructed from these assays improved substantially on the overall performance of the Salmonella assay. The in vitro assays which represented a range of three cell types and four end points did show substantial agreement among themselves, indicating that chemicals positive in one in vitro assay tended to be positive in the other in vitro assays. To help put this project into its proper context, we emphasize certain features of the study: 1) Standard protocols were used to mimic the major use of STTs worldwide--screening for mutagens and carcinogens; no attempt was made to optimize protocols for specific chemicals. 2) The 73 NTP chemicals and their 60% incidence of carcinogenicity are probably not representative of the universe of chemicals but rather reflect the recent chemical selection process for the NTP carcinogenicity assay. 3) The small, diverse group of chemicals precludes a meaningful evaluation of the predictive utility of chemical structure information. 4) The NTP is currently testing these same 73 chemicals in two in vivo STTs for chromosomal effects. 5) Complete data for an additional group of 30 to 40 NTP chemicals will be gathered on

  11. Toward in vitro biomarkers for developmental toxicity and their extrapolation to the in vivo situation

    NARCIS (Netherlands)

    Louisse, J.; Verwei, M.; Woutersen, R.A.; Blaauboer, B.J.; Rietjens, I.M.C.M.

    2012-01-01

    Introduction: Reliable in vitro and in silico assays as alternatives for in vivo developmental toxicity studies are urgently needed, for the replacement, reduction and refinement (3Rs) of animal use in toxicological research. Therefore, relevant biomarkers for in vivo developmental toxicity in in

  12. Toxicity of formaldehyde and acrolein mixtures : in vitro studies using nasal epithelial cells

    NARCIS (Netherlands)

    Cassee, F.R.; Stenhuis, W.S.; Groten, J.P.; Feron, V.J.

    1996-01-01

    In vitro studies with human and rat nasal epithelial cells were carried out to investigate the combined toxicity of formaldehyde and acrolein and the role of aldehyde dehydrogenases in this process. These studies showed that the toxic effect of mixtures of aldehydes was additive. In addition,

  13. Aquatic toxicity testing for hazard identification of engineered nanoparticles

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard

    been on the algal growth rate inhibition test and acute and chronic toxicity tests with crustaceans, all commonly applied in a regulatory context. The exposure timing measures included aging of ENPs in test media prior to incubation, and/or shortened exposure duration. For algae, shorter exposure...... toxicity of ENPs, the applicability of the generated data for hazard identification purposes is generally impaired by poor reproducibility and reliability of data, and limited understanding of the underlying effect mechanisms. Consequently, it has been questioned whether the standardized aquatic toxicity...... tests, developed for testing soluble compounds, are equally applicable for ENPs. The preconditions for aquatic toxicity tests include aqueous solubility of the chemical test compound and stability during incubation. These criteria are not met for ENPs, as they are suspended rather than dissolved...

  14. In vitro toxicity studies of polymer-coated gold nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Rayavarapu, Raja G; Petersen, Wilma; Manohar, Srirang; Van Leeuwen, Ton G [Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente, PO Box 217, 7500AE Enschede (Netherlands); Hartsuiker, Liesbeth; Otto, Cees [Medical Cell Biophysics, MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente, PO Box 217, 7500AE Enschede (Netherlands); Chin, Patrick; Van Leeuwen, Fijs W B [Division of Diagnostic Oncology, Netherlands Cancer Institute, 1066 CX Amsterdam (Netherlands); Janssen, Hans, E-mail: S.Manohar@utwente.nl [Division of Cell Biology, The Netherlands Cancer Institute, 1066 CX Amsterdam (Netherlands)

    2010-04-09

    We evaluated cellular responses to polymer-treated gold nanorods, which were synthesized using the standard wet-chemistry method that utilizes hexadecyltrimethylammonium bromide (CTAB). The nanorod dispersions were coated with either polystyrene sulfonate (PSS) or polyethylene glycol (PEG). Two sizes of nanorods were tested, with optical responses peaking at 628 and 773 nm. The cells were from mammary adenocarcinoma (SKBR3), Chinese Hamster Ovary (CHO), mouse myoblast (C2C12) and Human Leukemia (HL60) cell lines. Their mitochondrial function following exposure to the nanorods were assessed using the MTS assay. We found PEGylated particles to have superior biocompatibility compared with PSS-coated nanorods, which showed substantial cytotoxicity. Electron microscopy showed no cellular uptake of PEGylated particles compared with their PSS counterparts. PEGylated gold nanorods also exhibited better dispersion stability in the presence of cell growth medium; PSS-coated rods tended to flocculate or cluster. In the case of the PSS particles, toxicity correlated with surface area across the two sizes of nanorods studied.

  15. RESULTS OF SOLID PHASE SEDIMENT TOXICITY TESTS WITH REDUCED SEDIMENT VOLUMES FOR SEDIMENT TOXICITY

    Science.gov (United States)

    Development and standardization of sediment toxicity test methods for freshwater organisms have been underway for several years. Both EPA and ASTM have published methods for assessing the short-term (e.g., 10-d) toxicity of sediments to two benthic freshwater organisms (Hyalella ...

  16. EVALUATION OF ALTERNATIVE REFERENCE TOXICANTS FOR USE IN THE EARTHWORM TOXICITY TEST

    Science.gov (United States)

    The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However,the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants...

  17. Assessment of toxic potential of mycotoxin contaminated bread during in vitro human digestion on human B lymphoid cell line.

    Science.gov (United States)

    Monaci, Linda; Garbetta, Antonella; Angelis, Elisabetta De; Visconti, Angelo; Minervini, Fiorenza

    2015-01-05

    Ingestion of food is considered a major route of exposure to many contaminants including mycotoxins. The amount of mycotoxin resisting to the digestion process and potentially absorbable by the systemic circulation is only a smaller part of that ingested. In vitro digestion models turn useful for evaluating mycotoxins bioaccessibility during the intestinal transit and can be intended as a valuable tool for the assessment of mycotoxin bioavailability in food. In this paper we describe a study aimed at investigating toxicity of in vitro gastro-duodenal digests of mycotoxin contaminated bread collected along the digestion time-course. Toxicity tests were carried out on a sensitive RPMI lymphoid B cell line chosen as the most suitable lineage to assess toxicity retained by gastro-duodenal digests. In parallel, a chemical quantification of T-2 and HT-2 toxins contaminating the bread digests was accomplished during the gastric and duodenal transit. The digestive fluids undergoing chemical and toxicological analysis were collected at the beginning and end of gastric phase, and after completion of the duodenal phase. Results proved that a correlation between HT-2 content and toxicity did exist although a more persistent toxic activity was displayed in the later stage of the duodenal phase. This persistent toxicity might be explained by the co-occurrence of unknown HT-2-related conjugates or metabolites formed during digestion. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Toxicity testing in the 21 century: defining new risk assessment approaches based on perturbation of intracellular toxicity pathways.

    Directory of Open Access Journals (Sweden)

    Sudin Bhattacharya

    Full Text Available The approaches to quantitatively assessing the health risks of chemical exposure have not changed appreciably in the past 50 to 80 years, the focus remaining on high-dose studies that measure adverse outcomes in homogeneous animal populations. This expensive, low-throughput approach relies on conservative extrapolations to relate animal studies to much lower-dose human exposures and is of questionable relevance to predicting risks to humans at their typical low exposures. It makes little use of a mechanistic understanding of the mode of action by which chemicals perturb biological processes in human cells and tissues. An alternative vision, proposed by the U.S. National Research Council (NRC report Toxicity Testing in the 21(st Century: A Vision and a Strategy, called for moving away from traditional high-dose animal studies to an approach based on perturbation of cellular responses using well-designed in vitro assays. Central to this vision are (a "toxicity pathways" (the innate cellular pathways that may be perturbed by chemicals and (b the determination of chemical concentration ranges where those perturbations are likely to be excessive, thereby leading to adverse health effects if present for a prolonged duration in an intact organism. In this paper we briefly review the original NRC report and responses to that report over the past 3 years, and discuss how the change in testing might be achieved in the U.S. and in the European Union (EU. EU initiatives in developing alternatives to animal testing of cosmetic ingredients have run very much in parallel with the NRC report. Moving from current practice to the NRC vision would require using prototype toxicity pathways to develop case studies showing the new vision in action. In this vein, we also discuss how the proposed strategy for toxicity testing might be applied to the toxicity pathways associated with DNA damage and repair.

  19. Draft Test Guideline: Whole Sediment Acute Toxicity Invertebrates, Marine

    Science.gov (United States)

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  20. Developing a list of reference chemicals for testing alternatives to whole fish toxicity tests.

    Science.gov (United States)

    Schirmer, Kristin; Tanneberger, Katrin; Kramer, Nynke I; Völker, Doris; Scholz, Stefan; Hafner, Christoph; Lee, Lucy E J; Bols, Niels C; Hermens, Joop L M

    2008-11-11

    This paper details the derivation of a list of 60 reference chemicals for the development of alternatives to animal testing in ecotoxicology with a particular focus on fish. The chemicals were selected as a prerequisite to gather mechanistic information on the performance of alternative testing systems, namely vertebrate cell lines and fish embryos, in comparison to the fish acute lethality test. To avoid the need for additional experiments with fish, the U.S. EPA fathead minnow database was consulted as reference for whole organism responses. This database was compared to the Halle Registry of Cytotoxicity and a collation of data by the German EPA (UBA) on acute toxicity data derived from zebrafish embryos. Chemicals that were present in the fathead minnow database and in at least one of the other two databases were subject to selection. Criteria included the coverage of a wide range of toxicity and physico-chemical parameters as well as the determination of outliers of the in vivo/in vitro correlations. While the reference list of chemicals now guides our research for improving cell line and fish embryo assays to make them widely applicable, the list could be of benefit to search for alternatives in ecotoxicology in general. One example would be the use of this list to validate structure-activity prediction models, which in turn would benefit from a continuous extension of this list with regard to physico-chemical and toxicological data.

  1. Evaluation of the in vitro ocular toxicity of the fortified antibiotic eye drops prepared at the Hospital Pharmacy Departments

    Directory of Open Access Journals (Sweden)

    Anxo Fernández-Ferreiro

    2016-12-01

    Full Text Available The use of parenteral antibiotic eye drop formulations with non-marketed compositions or concentrations, commonly called fortified antibiotic eye drops, is a common practice in Ophthalmology in the hospital setting. The aim of this study was to evaluate the in vitro ocular toxicity of the main fortified antibiotic eye drops prepared in the Hospital Pharmacy Departments. We have conducted an in vitro experimental study in order to test the toxicity of gentamicin, amikacin, cefazolin, ceftazidime, vancomycin, colistimethate sodium and imipenem-cilastatin eye drops; their cytotoxicity and acute tissue irritation have been evaluated. Cell-based assays were performed on human stromal keratocytes, using a cell-based impedance biosensor system [xCELLigence Real-Time System Cell Analyzer (RTCA], and the Hen’s Egg Test for the ocular irritation tests. All the eye drops, except for vancomycin and imipenem, have shown a cytotoxic effect dependent on concentration and time; higher concentrations and longer exposure times will cause a steeper decline in the population of stromal keratocytes. Vancomycin showed a major initial cytotoxic effect, which was reverted over time; and imipenem appeared as a non-toxic compound for stromal cells. The eye drops with the highest irritating effect on the ocular surface were gentamicin and vancomycin. Those antibiotic eye drops prepared at the Hospital Pharmacy Departments included in this study were considered as compounds potentially cytotoxic for the ocular surface; this toxicity was dependent on the concentration used

  2. Rice seed toxicity tests for organic and inorganic substances

    Science.gov (United States)

    Wang, W.

    1994-01-01

    Plant seed toxicity tests can be used to evaluate hazardous waste sites and to assess toxicity of complex effluents and industrial chemicals. Conventional plant seed toxicity tests are performed using culture dishes containing filter paper. Some reports indicate that filter papers might interfere with the toxicity of inorganic substances. In this study, a plastic seed tray was used. Rice was used as the test species. A comparison of results in the literature and this study revealed that variation of test species, methods, exposure duration, and other factors may affect the test results. The results of this study showed that the order of decreasing toxicity of metal ions was Cu>Ag>Ni>Cd>Cr(VI)>Pb>Zn>Mn>NaF for rice. The test results were similar to those reported in the literature for lettuce Ag>Ni>Cd,Cu>Cr (VI)>Zn>Mn, millet Cu,Ni>Cd>Cr(VI)>Zn>Mn, and ryegrass Cu>Ni>Mn>>Pb>Cd>Zn> Al>Hg>Cr>Fe. The order of decreasing toxicity of organic herbicides was paraquat, 2,4-D>>glyphosate>bromacil.

  3. From in vivo to in vitro: The medical device testing paradigm shift.

    Science.gov (United States)

    Kerecman Myers, Dayna; Goldberg, Alan M; Poth, Albrecht; Wolf, Michael F; Carraway, Joseph; McKim, James; Coleman, Kelly P; Hutchinson, Richard; Brown, Ronald; Krug, Harald F; Bahinski, Anthony; Hartung, Thomas

    2017-05-25

    Amid growing efforts to advance the replacement, reduction, and refinement of the use of animals in research, there is a growing recognition that in vitro testing of medical devices can be more effective, both in terms of cost and time, and also more reliable than in vivo testing. Although the technological landscape has evolved rapidly in support of these concepts, regulatory acceptance of alternative testing methods has not kept pace. Despite the acceptance by regulators of some in vitro tests (cytotoxicity, gene toxicity, and some hemocompatibility assays), many toxicity tests still rely on animals (irritation, sensitization, acute toxicity, reproductive/developmental toxicity), even where other industrial sectors have already abandoned them. Bringing about change will require a paradigm shift in current approaches to testing - and a concerted effort to generate better data on risks to human health from exposure to leachable chemicals from medical devices, and to boost confidence in devices and alternative testing methods. To help advance these ideas, stir debate about best practices, and coalesce around a roadmap forward, the JHU-Center for Alternatives to Animal Testing (CAAT) hosted a symposium in Baltimore, Maryland, in December 2013 - believed to be the first gathering dedicated to the topic of in vitro testing of medical devices. Industry representatives, academics, and regulators in attendance presented evidence to support the unique strengths and challenges associated with the approaches currently in use as well as new methods under development, and drew next steps to push the field forward from their presentations and discussion.

  4. Custom-designed nanomaterial libraries for testing metal oxide toxicity.

    Science.gov (United States)

    Pokhrel, Suman; Nel, André E; Mädler, Lutz

    2013-03-19

    Advances in aerosol technology over the past 10 years have enabled the generation and design of ultrafine nanoscale materials for many applications. A key new method is flame spray pyrolysis (FSP), which produces particles by pyrolyzing a precursor solution in the gas phase. FSP is a highly versatile technique for fast, single-step, scalable synthesis of nanoscale materials. New innovations in particle synthesis using FSP technology, including variations in precursor chemistry, have enabled flexible, dry synthesis of loosely agglomerated, highly crystalline ultrafine powders (porosity ≥ 90%) of binary, ternary, and mixed-binary-and-ternary oxides. FSP can fulfill much of the increasing demand, especially in biological applications, for particles with specific material composition, high purity, and high crystallinity. In this Account, we describe a strategy for creating nanoparticle libraries (pure or Fedoped ZnO or TiO₂) utilizing FSP and using these libraries to test hypotheses related to the particles' toxicity. Our innovation lies in the overall integration of the knowledge we have developed in the last 5 years in (1) synthesizing nanomaterials to address specific hypotheses, (2) demonstrating the electronic properties that cause the material toxicity, (3) understanding the reaction mechanisms causing the toxicity, and (4) extracting from in vitro testing and in vivo testing in terrestrial and marine organisms the essential properties of safe nanomaterials. On the basis of this acquired knowledge, we further describe how the dissolved metal ion from these materials (Zn²⁺ in this Account) can effectively bind with different cell constituents, causing toxicity. We use Fe-S protein clusters as an example of the complex chemical reactions taking place after free metal ions migrate into the cells. As a second example, TiO₂ is an active material in the UV range that exhibits photocatalytic behavior. The induction of electron-hole (e⁻/h⁺) pairs followed by

  5. Alternative approaches for identifying acute systemic toxicity: Moving from research to regulatory testing.

    Science.gov (United States)

    Hamm, Jon; Sullivan, Kristie; Clippinger, Amy J; Strickland, Judy; Bell, Shannon; Bhhatarai, Barun; Blaauboer, Bas; Casey, Warren; Dorman, David; Forsby, Anna; Garcia-Reyero, Natàlia; Gehen, Sean; Graepel, Rabea; Hotchkiss, Jon; Lowit, Anna; Matheson, Joanna; Reaves, Elissa; Scarano, Louis; Sprankle, Catherine; Tunkel, Jay; Wilson, Dan; Xia, Menghang; Zhu, Hao; Allen, David

    2017-06-01

    Acute systemic toxicity testing provides the basis for hazard labeling and risk management of chemicals. A number of international efforts have been directed at identifying non-animal alternatives for in vivo acute systemic toxicity tests. A September 2015 workshop, Alternative Approaches for Identifying Acute Systemic Toxicity: Moving from Research to Regulatory Testing, reviewed the state-of-the-science of non-animal alternatives for this testing and explored ways to facilitate implementation of alternatives. Workshop attendees included representatives from international regulatory agencies, academia, nongovernmental organizations, and industry. Resources identified as necessary for meaningful progress in implementing alternatives included compiling and making available high-quality reference data, training on use and interpretation of in vitro and in silico approaches, and global harmonization of testing requirements. Attendees particularly noted the need to characterize variability in reference data to evaluate new approaches. They also noted the importance of understanding the mechanisms of acute toxicity, which could be facilitated by the development of adverse outcome pathways. Workshop breakout groups explored different approaches to reducing or replacing animal use for acute toxicity testing, with each group crafting a roadmap and strategy to accomplish near-term progress. The workshop steering committee has organized efforts to implement the recommendations of the workshop participants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Biological assays for aquatic toxicity testing

    CSIR Research Space (South Africa)

    Slabbert, JL

    1999-10-01

    Full Text Available and management purposes of effluents. If receiving water is used for drinking water purposes, the Ames Salmonella mutagenicity and toad embryo teratogenicity tests should be included in the battery of tests. Some of the rapid microbiotests, the petrozoan oxygen...

  7. In vitro antiplasmodial activity and toxicity assessment of plant extracts used in traditional malaria therapy in the Lake Victoria Region

    Directory of Open Access Journals (Sweden)

    Teresa Akeng'a Ayuko

    2009-08-01

    Full Text Available As part of our program screening the flora of the Lake Victoria Region, a total of 54 organic extracts from seven plant families (8 species were individually tested for antiplasmodial activity against chloroquine-sensitive [Sierra Leone (D-6] and chloroquine-resistant [Vietnam (W-2] strains. Only 22% of these extracts exhibited very high in vitro antiplasmodial activity. Six methanol (MeOH extracts and one chloroform extract showed in vitro antiplasmodial activity against the D-6 Plasmodium falciparum strain, while only three MeOH extracts were active against the W-2 strain. All of the ethyl acetate extracts proved to be inactive against both strains of P. falciparum. A brine shrimp cytotoxicity assay was used to predict the potential toxicity of the extracts. The cytotoxicity to antiplasmodial ratios for the MeOH extracts were found to be greater than 100, which could indicate that the extracts are of low toxicity.

  8. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  9. Similarity between the in vitro activity and toxicity of two different fungizone™ / lipofundin™ admixtures

    OpenAIRE

    Araújo,Ivonete Batista; Brito,C. Ramon N.; Urbano,Isabel A.; Dominici,Victor A.; Silva Filho,Miguel A.; Silveira,Walteçá L. L.; Damasceno,Bolívar P. G. L.; Medeiros,Aldo Cunha; Egito,E. Sócrates T.

    2005-01-01

    PURPOSE: Amphotericin B (AmB), an antifungal agent that presents a broad spectrum of activity, remains the gold standard in the antifungal therapy. However, sometimes the high level of toxicity forbids its clinical use. The aim of this work was to evaluate and compare the efficacy and toxicity in vitro of Fungizon™ (AmB-D) and two new different AmB formulations. METHODS: three products were studied: Fungizon™, and two Fungizon™ /Lipofundin™ admixtures, which were dilut...

  10. An optimized gene set for transcriptomics based neurodevelopmental toxicity prediction in the neural embryonic stem cell test

    NARCIS (Netherlands)

    Pennings, J.L.A.; Theunissen, P.T.; Piersma, A.H.|info:eu-repo/dai/nl/071276947

    2012-01-01

    The murine neural embryonic stem cell test (ESTn) is an in vitro model for neurodevelopmental toxicity testing. Recent studies have shown that application of transcriptomics analyses in the ESTn is useful for obtaining more accurate predictions as well as mechanistic insights. Gene expression

  11. Size-dependent toxicity of silver nanoparticles to bacteria, yeast, algae, crustaceans and mammalian cells in vitro.

    Science.gov (United States)

    Ivask, Angela; Kurvet, Imbi; Kasemets, Kaja; Blinova, Irina; Aruoja, Villem; Suppi, Sandra; Vija, Heiki; Käkinen, Aleksandr; Titma, Tiina; Heinlaan, Margit; Visnapuu, Meeri; Koller, Dagmar; Kisand, Vambola; Kahru, Anne

    2014-01-01

    The concept of nanotechnologies is based on size-dependent properties of particles in the 1-100 nm range. However, the relation between the particle size and biological effects is still unclear. The aim of the current paper was to generate and analyse a homogenous set of experimental toxicity data on Ag nanoparticles (Ag NPs) of similar coating (citrate) but of 5 different primary sizes (10, 20, 40, 60 and 80 nm) to different types of organisms/cells commonly used in toxicity assays: bacterial, yeast and algal cells, crustaceans and mammalian cells in vitro. When possible, the assays were conducted in ultrapure water to minimise the effect of medium components on silver speciation. The toxic effects of NPs to different organisms varied about two orders of magnitude, being the lowest (∼0.1 mg Ag/L) for crustaceans and algae and the highest (∼26 mg Ag/L) for mammalian cells. To quantify the role of Ag ions in the toxicity of Ag NPs, we normalized the EC50 values to Ag ions that dissolved from the NPs. The analysis showed that the toxicity of 20-80 nm Ag NPs could fully be explained by released Ag ions whereas 10 nm Ag NPs proved more toxic than predicted. Using E. coli Ag-biosensor, we demonstrated that 10 nm Ag NPs were more bioavailable to E. coli than silver salt (AgNO3). Thus, one may infer that 10 nm Ag NPs had more efficient cell-particle contact resulting in higher intracellular bioavailability of silver than in case of bigger NPs. Although the latter conclusion is initially based on one test organism, it may lead to an explanation for "size-dependent" biological effects of silver NPs. This study, for the first time, investigated the size-dependent toxic effects of a well-characterized library of Ag NPs to several microbial species, protozoans, algae, crustaceans and mammalian cells in vitro.

  12. Size-dependent toxicity of silver nanoparticles to bacteria, yeast, algae, crustaceans and mammalian cells in vitro.

    Directory of Open Access Journals (Sweden)

    Angela Ivask

    Full Text Available The concept of nanotechnologies is based on size-dependent properties of particles in the 1-100 nm range. However, the relation between the particle size and biological effects is still unclear. The aim of the current paper was to generate and analyse a homogenous set of experimental toxicity data on Ag nanoparticles (Ag NPs of similar coating (citrate but of 5 different primary sizes (10, 20, 40, 60 and 80 nm to different types of organisms/cells commonly used in toxicity assays: bacterial, yeast and algal cells, crustaceans and mammalian cells in vitro. When possible, the assays were conducted in ultrapure water to minimise the effect of medium components on silver speciation. The toxic effects of NPs to different organisms varied about two orders of magnitude, being the lowest (∼0.1 mg Ag/L for crustaceans and algae and the highest (∼26 mg Ag/L for mammalian cells. To quantify the role of Ag ions in the toxicity of Ag NPs, we normalized the EC50 values to Ag ions that dissolved from the NPs. The analysis showed that the toxicity of 20-80 nm Ag NPs could fully be explained by released Ag ions whereas 10 nm Ag NPs proved more toxic than predicted. Using E. coli Ag-biosensor, we demonstrated that 10 nm Ag NPs were more bioavailable to E. coli than silver salt (AgNO3. Thus, one may infer that 10 nm Ag NPs had more efficient cell-particle contact resulting in higher intracellular bioavailability of silver than in case of bigger NPs. Although the latter conclusion is initially based on one test organism, it may lead to an explanation for "size-dependent" biological effects of silver NPs. This study, for the first time, investigated the size-dependent toxic effects of a well-characterized library of Ag NPs to several microbial species, protozoans, algae, crustaceans and mammalian cells in vitro.

  13. Integrating in vitro data and physiologically based kinetic (PBK) modelling to assess the in vivo potential developmental toxicity of a series of phenols.

    Science.gov (United States)

    Strikwold, Marije; Spenkelink, Bert; de Haan, Laura H J; Woutersen, Ruud A; Punt, Ans; Rietjens, Ivonne M C M

    2017-05-01

    Toxicity outcomes derived in vitro do not always reflect in vivo toxicity values, which was previously observed for a series of phenols tested in the embryonic stem cell test (EST). Translation of in vitro data to the in vivo situation is therefore an important, but still limiting step for the use of in vitro toxicity outcomes in the safety assessment of chemicals. The aim of the present study was to translate in vitro embryotoxicity data for a series of phenols to in vivo developmental toxic potency values for the rat by physiologically based kinetic (PBK) modelling-based reverse dosimetry. To this purpose, PBK models were developed for each of the phenols. The models were parameterised with in vitro-derived values defining metabolism and transport of the compounds across the intestinal and placental barrier and with in silico predictions and data from the literature. Using PBK-based reverse dosimetry, in vitro concentration-response curves from the EST were translated into in vivo dose-response curves from which points of departure (PoDs) were derived. The predicted PoDs differed less than 3.6-fold from PoDs derived from in vivo toxicity data for the phenols available in the literature. Moreover, the in vitro PBK-based reverse dosimetry approach could overcome the large disparity that was observed previously between the in vitro and the in vivo relative potency of the series of phenols. In conclusion, this study shows another proof-of-principle that the in vitro PBK approach is a promising strategy for non-animal-based safety assessment of chemicals.

  14. Fungicidal activity of AKWATON and in vitro assessment of its toxic effects on animal cells.

    Science.gov (United States)

    Oulé, Mathias Kégnon; Staines, Kenton; Lightly, Tasia; Roberts, Loren; Traoré, Yannick Léandre; Dickman, Michael; Bernier, Anne-Marie; Diop, Lamine

    2015-01-01

    Acquired superficial fungal infections are among the most common infections. It is necessary to create new effective and non-toxic disinfectants. AKWATON is a new disinfectant of the polymeric guanidine family. Its fungicidal activity against Trichophyton mentagrophytes and its in vitro toxicity assessment were determined in this study. The MIC, minimum fungicidal concentration (MFC) and time required for its fungicidal activity at the MFC were evaluated using the official methods of analysis of the Association of Official Analytical Chemists, with modifications as recommended by the Canadian General Standards Board. The toxic effects of AKWATON and of four commercial disinfectants were evaluated on rat pancreatic (C2C12) and muscle (RnM5F) cells, using the trypan blue and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] methods. The MIC, MFC and time required for the fungicidal activity of AKWATON at the MFC were 0.025 % (w/v), 0.045 % (w/v) and 2.5 min, respectively. Cell cultures and the different tests carried out showed that the AKWATON-based disinfectant killed fewer cells than the commercial disinfectants, sparing 80 % of C2C12 cells and 65 % of RnM5F cells, whilst some of the well-known disinfectants currently on the market killed 85-100 % of cells. This study demonstrates that AKWATON has great potential as an odourless, colourless, non-corrosive and safe disinfectant for use in hospitals, the agriculture industry, farming and household facilities. © 2015 The Authors.

  15. The status of toxicity tests with sediment in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, R.P.A. [Companhia de Tecnologia e Saneamento Ambiental, Sao Paulo (Brazil)

    1995-12-31

    The earliest studies in Brazil aiming to evaluate sediment quality through toxicity tests started in the beginning of the 80`s. These were developed by the Environmental Sanitation Agency of Sao Paulo State (CETESB) in Cubatao River and Billings Reservoir, which are located in industrialized and populous regions. Elutriate phase sediment toxicity tests were run with Daphnia similis. In the Cubatao River Basin the combination of toxicity, chemistry data and benthic community structure provided clear indications of sites with different levels of pollution. At this time there was a consensus that the study of a complex compartment such as sediment needed improvements in sampling and analysis procedures. Only in the 90`s the investigations involving sediment toxicity assessment were resumed by CETESB, and it was clear that integrative studies were needed in order to make environmental quality assessment. This kind of studies were conducted by CETESB in some highly polluted areas of Sao Paulo State, Ceriodaphnia dubia and Photobacterium phosphoreum interstitial water tests and Hyalella sp whole sediment tests were run, and the results correlated with several sediment organic and inorganic contaminants. The Sediment Quality Triad proposed by Chapman was applied in one of these studies. This approach was extremely useful in interpreting the data. At the same time marine sediment toxicity tests were developed by CETESB in collaboration with Sao Paulo University, and tests were run with the amphipods Tiburonella viscana, Battyporeiapus bisetosus; tanaidacean Kalliapseudes shubarti and the echinoderm Lytechinus variegatus. The embryo test with L. variegatus was the most adequate in these studies. Nowadays there are other groups in some universities developing sediment toxicity tests with Hyalella and Chironomus in response to a growing concern in Brazil to establish adequate sediment quality assessment guidelines.

  16. Toxicity of Transition Metal Oxide Nanoparticles: Recent Insights from in vitro Studies

    Directory of Open Access Journals (Sweden)

    Robert S. Aronstam

    2010-10-01

    Full Text Available Nanotechnology has evolved to play a prominent role in our economy. Increased use of nanomaterials poses potential human health risk. It is therefore critical to understand the nature and origin of the toxicity imposed by nanomaterials (nanotoxicity. In this article we review the toxicity of the transition metal oxides in the 4th period that are widely used in industry and biotechnology. Nanoparticle toxicity is compellingly related to oxidative stress and alteration of calcium homeostasis, gene expression, pro-inflammatory responses, and cellular signaling events. The precise physicochemical properties that dictate the toxicity of nanoparticles have yet to be defined, but may include element-specific surface catalytic activity (e.g., metallic, semiconducting properties, nanoparticle uptake, or nanoparticle dissolution. These in vitro studies substantially advance our understanding in mechanisms of toxicity, which may lead to safer design of nanomaterials.

  17. Acute oral toxicity test and phytochemistry of some west african ...

    African Journals Online (AJOL)

    Background: Although there is increased acceptance and utilization of medicinal plants worldwide, many are used indiscriminately without recourse to any safety test. Thus, the need for toxicity tests to determine the safe dose for oral consumption. Objective: LD and phytochemistry of four medicinal plants 50 of West Africa ...

  18. A Mini-Nitrification Test for Toxicity Screening, Minntox

    DEFF Research Database (Denmark)

    Arvin, Erik; Dyreborg, Søren; Menck, C.

    1994-01-01

    There is a high demand for a rapid, simple, and inexpensive test for screening of the toxicity of wastewater, polluted groundwater and chemicals in order to protect sewage treatment plants and aquatic and terrestrial recipients. The mini-nitrification test, MINNTOX, presented here, fulfils...

  19. Acute Toxicity Tests Of Brewery Effluent on the Ostracoda ...

    African Journals Online (AJOL)

    The acute toxicity of brewery effluent to Strandesia prava Klie (crustacean, ostracoda) was determined in 24, 48 and 96 hour static bioassay under laboratory conditions. The test was conducted in replicates of 100, 50, 25, 12.5, 6.25 and 3.125% effluent concentrations. Mortality of the test organism increased with the ...

  20. In vitro growth-inhibitory effect of Brazilian plants extracts against Paenibacillus larvae and toxicity in bees

    Directory of Open Access Journals (Sweden)

    Mariana Piana

    2015-06-01

    Full Text Available American foulbrood (AFB is a serious worldwide spreading disease in bees caused by Paenibacillus larvae. Plants extracts are known to decrease or inhibit the growth of these bacteria. The purpose of this study was to evaluate the antimicrobial activity of Calendula. officinalis, Cariniana domestica, and Nasturtium officinale extracts against the P. larvae and to evaluate the toxicity of the extracts in bees. In vitro activity against P. larvae of the extracts was evaluated by micro dilution method and the minimal inhibitory concentrations (MICs were also determined. The concentrations used in the toxicity test were established based on the MIC values and by the spraying application method. The P. larvae was susceptible to the evaluated crude extract of C. officinalis and N. officinale. To C. domestica, only the ethyl acetate (EtAc fraction and n-butanol (BuOH fractions had activity against P. larvae. Toxicity analysis in bees showed no toxicity for N. officinale crude extract and for C. domestica BuOH fraction during 15 days of treatment, however, some deaths of bees occurred during the first three days of treatment with C. officinalis and C. domestica EtAc fraction. The results with these species were firstly described and showed that N. officinale crude extract and C. domestica BuOH fraction both presented not toxic effects in the concentration tested by the spraying application method, and can be a useful alternative for treatment or prevention of AFB.

  1. In vitro growth-inhibitory effect of Brazilian plants extracts against Paenibacillus larvae and toxicity in bees.

    Science.gov (United States)

    Piana, Mariana; de Brum, Thiele F; Boligon, Aline A; Alves, Camilla F S; de Freitas, Robson B; Nunes, Letícia T; Mossmann, Natalia J; Janovik, Vanessa; Jesus, Roberta S; Vaucher, Rodrigo A; Santos, Roberto C V; Athayde, Margareth L

    2015-01-01

    American foulbrood (AFB) is a serious worldwide spreading disease in bees caused by Paenibacillus larvae. Plants extracts are known to decrease or inhibit the growth of these bacteria. The purpose of this study was to evaluate the antimicrobial activity of Calendula. officinalis, Cariniana domestica, and Nasturtium officinale extracts against the P. larvae and to evaluate the toxicity of the extracts in bees. In vitro activity against P. larvae of the extracts was evaluated by micro dilution method and the minimal inhibitory concentrations (MICs) were also determined. The concentrations used in the toxicity test were established based on the MIC values and by the spraying application method. The P. larvae was susceptible to the evaluated crude extract of C. officinalis and N. officinale. To C. domestica, only the ethyl acetate (EtAc) fraction and n-butanol (BuOH) fractions had activity against P. larvae. Toxicity analysis in bees showed no toxicity for N. officinale crude extract and for C. domestica BuOH fraction during 15 days of treatment, however, some deaths of bees occurred during the first three days of treatment with C. officinalis and C. domestica EtAc fraction. The results with these species were firstly described and showed that N. officinale crude extract and C. domestica BuOH fraction both presented not toxic effects in the concentration tested by the spraying application method, and can be a useful alternative for treatment or prevention of AFB.

  2. Antibiotics and sweeteners in the aquatic environment: biodegradability, formation of phototransformation products, and in vitro toxicity.

    Science.gov (United States)

    Bergheim, Marlies; Gminski, Richard; Spangenberg, Bernd; Debiak, Malgorzata; Bürkle, Alexander; Mersch-Sundermann, Volker; Kümmerer, Klaus; Gieré, Reto

    2015-11-01

    In the present study, in vitro toxicity as well as biopersistence and photopersistence of four artificial sweeteners (acesulfame, cyclamate, saccharine, and sucralose) and five antibiotics (levofloxacin, lincomycin, linezolid, marbofloxacin, and sarafloxacin) and of their phototransformation products (PTPs) were investigated. Furthermore, antibiotic activity was evaluated after UV irradiation and after exposure to inocula of a sewage treatment plant. The study reveals that most of the tested compounds and their PTPs were neither readily nor inherently biodegradable in the Organisation for Economic Co-operation and Development (OECD)-biodegradability tests. The study further demonstrates that PTPs are formed upon irradiation with an Hg lamp (UV light) and, to a lesser extent, upon irradiation with a Xe lamp (mimics sunlight). Comparing the nonirradiated with the corresponding irradiated solutions, a higher chronic toxicity against bacteria was found for the irradiated solutions of linezolid. Neither cytotoxicity nor genotoxicity was found in human cervical (HeLa) and liver (Hep-G2) cells for any of the investigated compounds or their PTPs. Antimicrobial activity of the tested fluoroquinolones was reduced after UV treatment, but it was not reduced after a 28-day exposure to inocula of a sewage treatment plant. This comparative study shows that PTPs can be formed as a result of UV treatment. The study further demonstrated that UV irradiation can be effective in reducing the antimicrobial activity of antibiotics, and consequently may help to reduce antimicrobial resistance in wastewaters. Nevertheless, the study also highlights that some PTPs may exhibit a higher ecotoxicity than the respective parent compounds. Consequently, UV treatment does not transform all micropollutants into harmless compounds and may not be a large-scale effluent treatment option.

  3. Use of blue crab (Callinectes sapidus) embryos for toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R.; O`Malley, K. [Skidaway Inst. of Oceanography, Savannah, GA (United States)

    1995-12-31

    After fertilization, blue crab embryos develop in egg sacs attached to the female pleopods, often referred to as the sponge. Lipovitellin and lipid droplets in the egg sacs provide energy and nutrition for the developing embryos. Embryos were removed from the sponge and transferred to 24 well culture plates containing sea water with or without toxicants, Each well contained 10 embryos. After 7 to 10 days, embryos hatched to swimming zoea. The effects of toxicants at various concentrations on hatching were determined and the EC{sub 50} calculated. For example, the EC{sub 50} for tributyltin, fenvalerate and mercuric chloride were 50, 30 and 90 ng/liter, respectively. The hatching success of control embryos ranged from 95 to 98%. Formation of the heart, eyespot formation, appendage formation and utilization rate of lipovitellin were also effected by exposure to toxicants. At a low concentration of mercuric ion (30ng/liter) the heart formed, but there was no heart beat. Eyespot formation was abnormal in the presence of high concentrations of cadmium (2 {micro}g/liter) and zinc (5 {micro}g/liter), Crab embryos offer many advantages for toxicity testing of pure compounds or mixtures in water, including toxicity testing of sediment pore water. The crab embryos may also serve as models to understand the effect of specific toxicants on the heart and eye spots of crustaceans.

  4. Rainbow trout primary epidermal cell proliferation as an indicator of aquatic toxicity: an in vitro/in vivo exposure comparison.

    Science.gov (United States)

    Kilemade, Michael; Lyons-Alcantara, Maria; Rose, Tina; Fitzgerald, Richard; Mothersill, Carmel

    2002-10-02

    Little or no work has been carried out on primary cell cultures in terms of cellular proliferation and toxicity studies. Cell proliferation represents one of the most relevant cellular functions. Anti-PCNA antibodies have aroused considerable interest recently as potential immunocytochemical markers of proliferation for use in toxicity studies. In this study, PCNA methodology, which was developed primarily for mammalian tissues, was adapted to rainbow trout (Oncorhynchus mykiss (R.)) primary cultured epidermal cells exposed in vivo i.e. whole animal exposures and in vitro for the study of the ecotoxicological potential of the aromatic amine, 2,4-dichloroaniline (2,4-DCA), a member of a little studied and widespread class of aquatic pollutants. There are many approaches to assess the proliferative activity of cells. Immunocytochemical methods offer a high sensitivity and specificity. The immunohistochemical avidin-biotin complex (ABC) method was used for the detection and quantification of PCNA, one of the best-known endogenous proliferation markers, applying the mammalian monoclonal antibody PC-10 to formalin-fixed primary cultures of rainbow trout skin. Here we describe our experience with the immunocytochemical detection and quantification of this proliferation marker. Results indicate that the antibody cross reacts with the corresponding rainbow trout epitope and that the alterations in PCNA labelling in the in vivo and in vitro exposed cultures followed similar patterns. This paper presents data on the validation of rainbow trout primary epidermal culture as an in vitro ecotoxicity model with epidermal proliferation as an endpoint. It can be concluded that cellular proliferation could be used as an indicator of the aquatic toxicity potential of xenobiotics. Correlations between cellular proliferation responses in primary cultures derived from in vivo exposed rainbow trout and primary cultures exposed in vitro were assessed. A dose-response was evidenced in both

  5. In vitro and acute in vivo toxicity of the aqueous and chloroformic ...

    African Journals Online (AJOL)

    This study was conducted to generate a toxicological profile of Rapanea melanophloeos, a medicinal plant widely utilized in traditional medicine to treat helminthiasis,using brine shrimp (Artemia salina) and Sprague Dawley (SD) rats. The aqueous extract showed potent in vitro toxicity to brine shrimp with a median lethal ...

  6. Modeling Zebrafish Developmental Toxicity using a Concurrent In vitro Assay Battery (SOT)

    Science.gov (United States)

    We describe the development of computational models that predict activity in a repeat-dose zebrafish embryo developmental toxicity assay using a combination of physico-chemical parameters and in vitro (human) assay measurements. The data set covered 986 chemicals including pestic...

  7. Functional toxicology: tools to advance the future of toxicity testing

    Science.gov (United States)

    Gaytán, Brandon D.; Vulpe, Chris D.

    2014-01-01

    The increased presence of chemical contaminants in the environment is an undeniable concern to human health and ecosystems. Historically, by relying heavily upon costly and laborious animal-based toxicity assays, the field of toxicology has often neglected examinations of the cellular and molecular mechanisms of toxicity for the majority of compounds—information that, if available, would strengthen risk assessment analyses. Functional toxicology, where cells or organisms with gene deletions or depleted proteins are used to assess genetic requirements for chemical tolerance, can advance the field of toxicity testing by contributing data regarding chemical mechanisms of toxicity. Functional toxicology can be accomplished using available genetic tools in yeasts, other fungi and bacteria, and eukaryotes of increased complexity, including zebrafish, fruit flies, rodents, and human cell lines. Underscored is the value of using less complex systems such as yeasts to direct further studies in more complex systems such as human cell lines. Functional techniques can yield (1) novel insights into chemical toxicity; (2) pathways and mechanisms deserving of further study; and (3) candidate human toxicant susceptibility or resistance genes. PMID:24847352

  8. Functional toxicology: tools to advance the future of toxicity testing.

    Science.gov (United States)

    Gaytán, Brandon D; Vulpe, Chris D

    2014-01-01

    The increased presence of chemical contaminants in the environment is an undeniable concern to human health and ecosystems. Historically, by relying heavily upon costly and laborious animal-based toxicity assays, the field of toxicology has often neglected examinations of the cellular and molecular mechanisms of toxicity for the majority of compounds-information that, if available, would strengthen risk assessment analyses. Functional toxicology, where cells or organisms with gene deletions or depleted proteins are used to assess genetic requirements for chemical tolerance, can advance the field of toxicity testing by contributing data regarding chemical mechanisms of toxicity. Functional toxicology can be accomplished using available genetic tools in yeasts, other fungi and bacteria, and eukaryotes of increased complexity, including zebrafish, fruit flies, rodents, and human cell lines. Underscored is the value of using less complex systems such as yeasts to direct further studies in more complex systems such as human cell lines. Functional techniques can yield (1) novel insights into chemical toxicity; (2) pathways and mechanisms deserving of further study; and (3) candidate human toxicant susceptibility or resistance genes.

  9. Functional toxicology: tools to advance the future of toxicity testing

    Directory of Open Access Journals (Sweden)

    Brandon David Gaytán

    2014-05-01

    Full Text Available The increased presence of chemical contaminants in the environment is an undeniable concern to human health and ecosystems. Historically, by relying heavily upon costly and laborious animal-based toxicity assays, the field of toxicology has often neglected examinations of the cellular and molecular mechanisms of toxicity for the majority of compounds – information that, if available, would strengthen risk assessment analyses. Functional toxicology, where cells or organisms with gene deletions or depleted proteins are used to assess genetic requirements for chemical tolerance, can advance the field of toxicity testing by contributing data regarding chemical mechanisms of toxicity. Functional toxicology can be accomplished using available genetic tools in yeasts, other fungi and bacteria, and eukaryotes of increased complexity, including zebrafish, fruit flies, rodents, and human cell lines. Underscored is the value of using less complex systems such as yeasts to direct further studies in more complex systems such as human cell lines. Functional techniques can yield (1 novel insights into chemical toxicity; (2 pathways and mechanisms deserving of further study; and (3 candidate human toxicant susceptibility or resistance genes.

  10. Boar spermatozoa successfully predict mitochondrial modes of toxicity: implications for drug toxicity testing and the 3R principles.

    Science.gov (United States)

    Vicente-Carrillo, A; Edebert, I; Garside, H; Cotgreave, I; Rigler, R; Loitto, V; Magnusson, K E; Rodríguez-Martínez, H

    2015-04-01

    Replacement of animal testing by in vitro methods (3-R principles) requires validation of suitable cell models, preferably obtained non-invasively, defying traditional use of explants. Ejaculated spermatozoa are highly dependent on mitochondrial production and consumption of ATP for their metabolism, including motility display, thus becoming a suitable model for capturing multiple modes of action of drugs and other chemicals acting via mitochondrial disturbance. In this study, a hypothesis was tested that the boar spermatozoon is a suitable cell type for toxicity assessment, providing a protocol for 3R-replacement of animals for research and drug-testing. Boar sperm kinetics was challenged with a wide variety of known frank mito-toxic chemicals with previously shown mitochondrial effects, using a semi-automated motility analyser allied with real-time fluorescent probing of mitochondrial potential (MitoTracker & JC-1). Output of this sperm assay (obtained after 30 min) was compared to cell viability (ATP-content, data obtained after 24-48 h) of a hepatome-cell line (HepG2). Results of compound effects significantly correlated (Pbreeding boars, are confirmed as suitable biosensors for preclinical toxicology screening and ranking of lead compounds in the drug development processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. The MTT assay as tool to evaluate and compare excipient toxicity in vitro on respiratory epithelial cells.

    Science.gov (United States)

    Scherliess, Regina

    2011-06-15

    There are not many excipients already approved in drug products for the use in the respiratory tract. In this study, a rapid in vitro screening procedure to assess and compare acute toxicity of soluble excipient substances on respiratory epithelial cells utilising the Calu-3 cell line is presented. The test substances are either dissolved in HBSS+HEPES buffer or are directly applied to the cellular surface. After 4h incubation, the substances are removed and the cell viability is assessed using an MTT assay. The tested excipients include polysorbate 20 and 80, lactose and povidone 30 as well as glycerol and propylene glycol as examples of excipients already being used in formulations for application in the respiratory tract. These substances are sorted according to their toxic effect and new excipients not yet used in the respiratory tract like HPMC can be classified in this scheme. With this, besides information from systemic toxicity tests, a first valuation of the acute toxic effect of the substance on respiratory epithelial cells is gained. This can aid in the choice of new excipients being necessary for modern respiratory formulations comprising new active compounds as biomolecules or new delivery strategies such as sustained or prolonged delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Scanning respirometer for toxicity tests using micro-organisms

    Science.gov (United States)

    Zhang, Min-Quan; Li, Xiang-Ming; Wong, Yuk-Shan; Kwan, FolkYear

    1995-09-01

    A novel respirometer is developed for microbial toxicity tests. The respirometer is based on luminescent quenching of oxygen to measure the concentration of dissolved oxygen in cell vessels and evaluate the toxicity of chemicals by monitoring the effect of toxicants on cell respiration of micro-organisms. The oxygen sensing element is ruthenium complex absorbed on the surface of silica particles followed by immobilizing on a silicone rubber film. The oxygen sensing film is coated on the inner bottom of a transparent cell vessel. A sensing device scanning under the cell vessel is used for remote monitoring of the oxygen concentration inside the cell vessels so that a large number of samples can be handled in one batch. The sensing device includes the excitation light sources and an optical cable connected to a filter and a photomultiplier tube for detecting the luminescence in the cell vessel which can then be related to the dissolved oxygen concentration inside the cell vessel. The movement of the sensing device and data acquisition are controlled by a personal computer. The toxicity of heavy metals to activated sludge, soil bacteria and E. coli were tested using the present device. The scanning respirometer provides a new alternative for fast and large scale screening and monitoring of toxicants using micro-organisms.

  13. 40 CFR 797.1950 - Mysid shrimp chronic toxicity test.

    Science.gov (United States)

    2010-07-01

    ... the test organisms, including the scientific name and method of verification, average length, age... concentrations, including method validations and reagent blanks. (12) The data records of the holding... apply to this guideline: (1) “Chronic toxicity test” means a method used to determine the concentration...

  14. Controlling type-1 error rates in whole effluent toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.; Johnson, S.C. [EcoAnalysis, Inc., Ojai, CA (United States)

    1995-12-31

    A form of variability, called the dose x test interaction, has been found to affect the variability of the mean differences from control in the statistical tests used to evaluate Whole Effluent Toxicity Tests for compliance purposes. Since the dose x test interaction is not included in these statistical tests, the assumed type-1 and type-2 error rates can be incorrect. The accepted type-1 error rate for these tests is 5%. Analysis of over 100 Ceriodaphnia, fathead minnow and sea urchin fertilization tests showed that when the test x dose interaction term was not included in the calculations the type-1 error rate was inflated to as high as 20%. In a compliance setting, this problem may lead to incorrect regulatory decisions. Statistical tests are proposed that properly incorporate the dose x test interaction variance.

  15. Prion Propagation and Toxicity Occur In Vitro with Two-Phase Kinetics Specific to Strain and Neuronal Type

    Science.gov (United States)

    Hannaoui, Samia; Maatouk, Layal; Privat, Nicolas; Levavasseur, Etienne; Faucheux, Baptiste A.

    2013-01-01

    Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative disorders that occur in humans and animals. The neuropathological hallmarks of TSEs are spongiosis, glial proliferation, and neuronal loss. The only known specific molecular marker of TSEs is the abnormal isoform (PrPSc) of the host-encoded prion protein (PrPC), which accumulates in the brain of infected subjects and forms infectious prion particles. Although this transmissible agent lacks a specific nucleic acid component, several prion strains have been isolated. Prion strains are characterized by differences in disease outcome, PrPSc distribution patterns, and brain lesion profiles at the terminal stage of the disease. The molecular factors and cellular mechanisms involved in strain-specific neuronal tropism and toxicity remain largely unknown. Currently, no cellular model exists to facilitate in vitro studies of these processes. A few cultured cell lines that maintain persistent scrapie infections have been developed, but only two of them have shown the cytotoxic effects associated with prion propagation. In this study, we have developed primary neuronal cultures to assess in vitro neuronal tropism and toxicity of different prion strains (scrapie strains 139A, ME7, and 22L). We have tested primary neuronal cultures enriched in cerebellar granular, striatal, or cortical neurons. Our results showed that (i) a strain-specific neuronal tropism operated in vitro; (ii) the cytotoxic effect varied among strains and neuronal cell types; (iii) prion propagation and toxicity occurred in two kinetic phases, a replicative phase followed by a toxic phase; and (iv) neurotoxicity peaked when abnormal PrP accumulation reached a plateau. PMID:23255799

  16. Toxicity of inorganic arsenic and its metabolites on haematopoietic progenitors "in vitro": comparison between species and sexes.

    Science.gov (United States)

    Ferrario, Daniele; Croera, Cristina; Brustio, Roberta; Collotta, Angelo; Bowe, Gerard; Vahter, Marie; Gribaldo, Laura

    2008-07-30

    Inorganic arsenic (iAs) and its metabolites are transferred to the foetus through the placental barrier and this exposure can compromise the normal development of the unborn. For this reason, we assessed the toxicity of sodium arsenite (iAs(III)) and its metabolites dimethylarsinic acid (DMA(V)), monomethylarsonic acid (MMA(V)) and monomethylarsonous acid (MMA(III)) on human haematopoietic cord blood cells and murine bone marrow progenitors in vitro, looking at the effects induced at different concentrations in the two genders. The expression of two enzymes responsible for arsenic biotransformation arsenic methyltranferase (AS3MT) and glutathione S-transferase omega 1 (GSTO1) was evaluated in human cord blood cells. Cord blood and bone marrow cells were exposed in vitro to iAs(III) at a wide range of concentrations: from 0.0001 microM to 10 microM. The methylated arsenic metabolites were tested only on human cord blood cells at concentrations ranging from 0.00064 microM to 50 microM. The results showed that iAs(III) was toxic on male and female colony forming units to about the same extent both in human and in mouse. Surprisingly, very low concentrations of iAs(III) increased the proliferation rate of both human and murine female cells, while male cells showed no significant modulation. MMA(V) and DMA(V) did not exert detectable toxicity on the cord blood cells, while MMA(III) had a marked toxic effect both in male and female human progenitors. AS3MT mRNA expression was not induced in human cord blood cells after iAs(III) exposure. GSTO1 expression decreased after MMA(III) treatment. This study provides evidence that exposure to iAs(III) and MMA(III) at muM concentrations is associated with immunosuppression in vitro.

  17. Use of In Vitro Morphogenesis of Mouse Embryoid Bodies to Assess Developmental Toxicity of Therapeutic Drugs Contraindicated in Pregnancy.

    Science.gov (United States)

    Warkus, Erica L L; Yuen, Angela A Y Q; Lau, Caroline G Y; Marikawa, Yusuke

    2016-01-01

    In utero exposure to certain chemicals can impair embryo development, causing embryonic death, growth retardation, or severe birth defects. Establishment of effective in vitro tests is crucial for identifying developmental toxicants and for reducing the financial and ethical burden of animal-based tests. Previously, we created an in vitro morphogenesis model using pluripotent P19C5 mouse embryonal carcinoma stem cells that mimics the process of gastrulation and axial body elongation of embryos. Because many birth defects are caused by dysregulation of cellular behaviors during embryogenesis, the morphogenesis model may serve as a unique tool to investigate the impacts of developmental toxicants. The aim of this study is to evaluate the applicability and limitations of the model using 20 therapeutic drugs, 16 of which are contraindicated in pregnancy and 4 are considered safe. P19C5 embryoid bodies (EBs) were exposed to different concentrations of drugs during 4 days of 3-dimensional culture. The treatment effects on growth and morphogenesis were analyzed using morphometric measurements of EB size and shape, respectively. Viability assays of P19C5 cells and NIH/3T3 fibroblasts were used to determine the drug concentrations that caused general cytotoxicity and those that selectively diminished P19C5 proliferation relative to NIH/3T3 proliferation. Thirteen contraindicated drugs diminished P19C5 cell proliferation, reduced EB growth, or altered morphogenesis at concentrations below generally cytotoxic levels. Two safe drugs also exhibited these impacts at the highest concentration tested. Although additional validation studies are required, this study introduces morphogenesis-based stem cell models as potentially effective in vitro tools for developmental toxicity research. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Mollusc reproductive toxicity tests - Development and validation of test guidelines

    DEFF Research Database (Denmark)

    Ducrot, Virginie; Holbech, Henrik; Kinnberg, Karin Lund

    . Draft standard operating procedures (SOPs) have been designed based upon literature and expert knowledge from project partners. Pre-validation studies have been implemented to validate the proposed test conditions and identify issues in performing the SOPs and analyzing test results. Pre-validation work...... for P. antipodarum consisted in a comparative 28-day study between four laboratories and with two test substances: cadmium (Cd) and bisphenol A (BPA). For L. stagnalis, pre-validation consisted in a comparative 56-day study between six laboratories and with two test substances: Cd and tributyltin (TBT...... in partner laboratories and exhibited homogenous age and size at the beginning of the tests. All laboratories found a concentration-dependent decrease of fecundity in both species under Cd exposure. Values of NOECs and LOECs were generally homogenous among laboratories. Results of the pre-validation studies...

  19. Evaluation of Complex Toxicity of Canbon Nanotubes and Sodium Pentachlorophenol Based on Earthworm Coelomocytes Test.

    Science.gov (United States)

    Yang, Yang; Xiao, Yao; Li, Mei; Ji, Funian; Hu, Changwei; Cui, Yibin

    2017-01-01

    As a standard testing organism in soil ecosystems, the earthworm Eisenia fetida has been used widely in toxicity studies. However, tests at the individual level are time- and animal-consuming, with limited sensitivity. Earthworm coelomocytes are important for the assimilation and elimination of exogenous compounds and play a key role in the processes of phagocytosis and inflammation. In this study, we explored an optimal condition to culture coelomocytes of E. fetida in vitro and investigated the cytotoxicity of multiwalled carbon nanotubes (MWCNTs) and sodium pentachlorophenol (PCP-Na) using coelomocytes via evaluating lethal toxicity, oxidative stress, membrane damage, and DNA damage. The results showed that coelomocytes can be successfully cultured in vitro in primary under the RPMI-1640 medium with 2-4×104 cells/well (1-2×105 cells/mL) in 96-well plates at 25°C without CO2. Both MWCNTs and PCP-Na could cause oxidative damage and produce ROS, an evidence for lipid peroxidation with MDA generation and SOD and CAT activity inhibition at high stress. The two chemicals could separately damage the cell membrane structure, increasing permeability and inhibiting mitochondrial membrane potential (MMP). In addition, our results indicate that PCP-Na may be adsorbed onto MWCNTs and its toxicity on earthworm was accordingly alleviated, while a synergetic effect was revealed when PCP-Na and MWCNTs were added separately. In summary, coelomocyte toxicity in in vitro analysis is a sensitive method for detecting the adverse effects of carbon nanotubes combined with various pollutants.

  20. In vitro susceptibility testing of Dientamoeba fragilis.

    Science.gov (United States)

    Nagata, N; Marriott, D; Harkness, J; Ellis, J T; Stark, D

    2012-01-01

    Dientamoeba fragilis is a commonly encountered trichomonad which has been implicated as a cause of gastrointestinal disease in humans. Despite the frequency of reports recording infections with this parasite, little research has been undertaken in terms of antimicrobial susceptibility. The aim of this study was to evaluate the susceptibility of D. fragilis to several commonly used antiparasitic agents: diloxanide furoate, furazolidone, iodoquinol, metronidazole, nitazoxanide, ornidazole, paromomycin, secnidazole, ronidazole, tetracycline, and tinidazole. Antibiotic susceptibility testing was performed on four clinical strains of D. fragilis, designated A, E, M, and V, respectively. Molecular testing followed, and all strains were determined to be genotype 1. The activities of antiprotozoal compounds at concentrations ranging from 2 μg/ml to 500 μg/ml were determined via cell counts of D. fragilis trophozoites grown in dixenic culture. Minimum lethal concentrations (MLCs) were as follows: ornidazole, 8 to 16 μg/ml; ronidazole, 8 to 16 μg/ml; tinidazole, 31 μg/ml; metronidazole, 31 μg/ml; secnidazole, 31 to 63 μg/ml; nitazoxanide, 63 μg/ml; tetracycline, 250 μg/ml; furazolidone, 250 to 500 μg/ml; iodoquinol, 500 μg/ml; paromomycin, 500 μg/ml; and diloxanide furoate, >500 μg/ml. This is the first study to report the profiles of susceptibility to a wide range of commonly used treatments for clinical isolates of D. fragilis. Our study indicated 5-nitroimidazole derivatives to be the most active compounds in vitro against D. fragilis.

  1. Assuring safety without animal testing: the case for the human testis in vitro.

    Science.gov (United States)

    Chapin, Robert E; Boekelheide, Kim; Cortvrindt, Rita; van Duursen, Majorie B M; Gant, Tim; Jegou, Bernard; Marczylo, Emma; van Pelt, Ans M M; Post, Janine N; Roelofs, Maarke J E; Schlatt, Stefan; Teerds, Katja J; Toppari, Jorma; Piersma, Aldert H

    2013-08-01

    From 15 to 17 June 2011, a dedicated workshop was held on the subject of in vitro models for mammalian spermatogenesis and their applications in toxicological hazard and risk assessment. The workshop was sponsored by the Dutch ASAT initiative (Assuring Safety without Animal Testing), which aims at promoting innovative approaches toward toxicological hazard and risk assessment on the basis of human and in vitro data, and replacement of animal studies. Participants addressed the state of the art regarding human and animal evidence for compound mediated testicular toxicity, reviewed existing alternative assay models, and brainstormed about future approaches, specifically considering tissue engineering. The workshop recognized the specific complexity of testicular function exemplified by dedicated cell types with distinct functionalities, as well as different cell compartments in terms of microenvironment and extracellular matrix components. This complexity hampers quick results in the realm of alternative models. Nevertheless, progress has been achieved in recent years, and innovative approaches in tissue engineering may open new avenues for mimicking testicular function in vitro. Although feasible, significant investment is deemed essential to be able to bring new ideas into practice in the laboratory. For the advancement of in vitro testicular toxicity testing, one of the most sensitive end points in regulatory reproductive toxicity testing, such an investment is highly desirable. Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  2. Freshwater toxicity testing using rehydrated Philodina sp. (Rotifera) as test animals.

    Science.gov (United States)

    Snell, Terry W; Johnston, Rachel K; Matthews, Amelia B

    2017-10-01

    Rotifers have become widely used in aquatic toxicology as a rapid screening test for toxicity. The commercial availability of diapausing embryos (cysts) have facilitated their popularity because test animals can be obtained without having to master the details of culturing. Other rotifer species have life stages capable of surviving desiccation and also could be used in non-culture systems for toxicity assessment. In this article, we describe a system for toxicity testing in freshwater based on rehydrating desiccated bdelloid rotifers in the genus Philodina. These animals can remain in this anhydrobiotic state for more than one year and then rehydrate within hours to provide animals for toxicity tests. We describe three endpoints: a 1.5 h ingestion test, a 24 h mortality test, and a five day reproductive test. The latter test requires feeding and a method using a dried commercial product is explained. Using desiccated rotifers and dried food in toxicity tests make this system especially attractive because of its flexibility and low threshold of biological expertise required to execute the tests. The use of the Philodina toxicity test is illustrated with four metals: copper, lead, mercury and cadmium. Reproduction generally was the most sensitive endpoint, with EC50s of 0.33, 0.44, 0.60, and 0.12 mg/L, respectively. Ingestion was a close second with EC50s of 0.13, 1.64, 0.64, and 6.26 mg/L, respectively. © 2017 Wiley Periodicals, Inc.

  3. In vitro effects of selected environmental toxicants on two heme synthesis enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.J.; Williams, H.L.; Slater, S.; Haut, M.J.; Altstatt, L.B.

    1985-11-01

    Benzene and some of its substitution products become environmental toxicants due to improper disposal procedures. Benzene has been found to alter heme and globin synthesis in anucleate rabbit reticulocytes (Forte et al., 1976; Wildman et al., 1976) and based on these findings we felt it would be useful to determine what, if any, effect these derivatives would have on heme synthesis in vitro by studying their influence on delta-aminolevulinic acid synthetase (ALAS) and ferrochelatase (FC) activities in rat liver homogenates. ALAS was measured according to Ebert et al. (1970). FC was measured after Williams et al. (1980). Final concentrations of each added compound to the reaction mixture were 10(-3) to 10(-6) M. Normal values for rat liver ALAS were 250-350 nmol ALA/g protein/30 min, mean 290 +/- 40, and for FC were 12-40 mumol heme/g protein/45 min, mean 20 +/- 7. At 10(-3) M and lower concentrations these compounds inhibited ALAS and stimulated FC activities. Their effect on ALAS activity expressed as percentage of control of three analyses performed in triplicate +/- SEM was: o- and p-dinitrobenzenes-46 +/- 2; trinitrotoluenes-55 +/- 2; dinitrotoluenes-70 +/- 2; and amino-dinitrotoluenes-171 +/- 4. The stimulatory effect of these compounds expressed as percentage of control +/- SEM on FC was: dinitrotoluenes-171 +/- 3; dinitrobenzenes-152 +/- 3; trinitrotoluenes-142 +/- 4; and amino-dinitrotoluenes-130 +/- 4. Other classes of compounds tested did not significantly affect these enzymes at the same concentrations. These in vitro techniques may prove useful for predicting in vivo toxicologic effects of pollutants on species of interest.

  4. In vivo and in vitro testing for selenium and selenium compounds bioavailability assessment in foodstuff.

    Science.gov (United States)

    Moreda-Piñeiro, Jorge; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

    2017-03-04

    The assessment of selenium and selenium species bioavailability in foodstuff is of special concern on the context of human nutrition. In vivo (human and animal), and in vitro tests are important approaches for estimating the bioavailability of toxic and essential compounds to humans. An overview on in vivo and in vitro bioavailability assays for releasing selenium and selenium species in foodstuffs is summarized. Se and Se species content in a foodstuff critically influence Se bioavailability and bioactivity to humans and animals. Se bioavailability is affected by foodstuff-matrix major composition and minor components. Foodstuffs processing and/or treatments could enhancement or decrease Se bioavailability. Experimental conditions such as the selection of healthy status of examined people (in in vivo humans approaches), the selection of animal model (in vivo animals approaches), or the selection of GI conditions (in in vitro tests) could determines the results. Thus, international standardized protocol for in vivo and in vitro approaches assessment is mandatory.

  5. Effects of using synthetic sea salts when measuring and modeling copper toxicity in saltwater toxicity tests.

    Science.gov (United States)

    Arnold, W Ray; Cotsifas, Jeffrey S; Winter, Anna R; Klinck, Joel S; Smith, D Scott; Playle, Richard C

    2007-05-01

    Synthetic sea salts are often used to adjust the salinity of effluent, ambient, and laboratory water samples to perform toxicity tests with marine and estuarine species. The U.S. Environmental Protection Agency (U.S. EPA) provides guidance on salinity adjustment in its saltwater test guidelines. The U.S. EPA suggests using commercial sea salt brands, such as Forty Fathoms (now named Crystal Sea Marinemix, Bioassay Grade), HW Marinemix, or equivalent salts to adjust sample salinity. Toxicity testing laboratories in Canada and the United States were surveyed to determine synthetic sea salt brand preference. The laboratories (n = 27) reported using four brands: Crystal Sea Marinemix (56%), HW Marinemix (22%), Instant Ocean (11%), and Tropic Marin (11%). Saline solutions (30 g/L) of seven synthetic sea salts were analyzed for dissolved copper and dissolved organic carbon (DOC) content. Brands included those listed above plus modified general-purpose salt (modified GP2), Kent Marine, and Red Sea Salt. The synthetic sea salts added from analysis of variance, Tukey, alpha = 0.05, p copper toxicity. However, the measured dissolved copper effective concentration 50% (EC50) for Crystal Sea Marinemix was 9.7 microg Cu/L, similar to other tested sea salts. Analysis indicates that the organic matter in Crystal Sea Marinemix differs considerably from that of natural organic matter. On the basis of consistently adding little DOC and little dissolved copper, GP2 and Kent Marine are the best salts to use.

  6. A mechanistic redefinition of adverse effects - a key step in the toxicity testing paradigm shift.

    Science.gov (United States)

    Boekelheide, Kim; Andersen, Melvin E

    2010-01-01

    The efforts of the committee that produced the report on Toxicity Testing in the 21st Century reflected the need to look at the issue of assessing risks to humans from exposure to various chemicals through a lens of 21st century biology. The problem - determining if there is a risk of specific exposures - is as old as humanity; every generation brings its own perspective and tools for examining the problem and coming to answers and solutions. Bringing this generation's tools to bear requires us to see the problem of chemical risk assessment in a different light, both in terms of testing of toxicity pathways in vitro and in the interpretation of the tests for estimating whether exposures will be safe. One key issue will be to assess when pathway perturbations are believed to be excessive, i.e., when they are deemed adverse. Redefinition of adversity based on in vitro testing will require a new perception of dose response functions as probabilities of failures, with multiple underlying processes acting sequentially and in parallel leading to failure at a cellular and an organism level. These dose response relationships for adversity will also require a computational systems biology approach for examining toxicity pathway dynamics and stress pathway overload. While the overall approach of defining adversity for in vitro endpoints and using this definition of adversity for risk assessment can be painted in broad brush strokes, as we have done here for DNA-reactive compounds, it will take implementation with a series of prototypes to show the process in practice.

  7. In vitro toxicity, antiplatelet and acetylcholinesterase inhibition of Buddleja thyrsoides Lam. leaves.

    Science.gov (United States)

    Mahlke, Janaína Dorneles; Boligon, Aline Augusti; Machado, Michel Mansur; Athayde, Margareth Linde

    2012-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder resulting in impaired memory and behaviour of remarkable socio-economic impact. A decrease in cholinergic activity is a key event in the biochemical of AD. Buddleja thyrsoides is a plant widely distributed in Southern parts of South America. In Brazilian traditional medicine, the infusion of its leaves and flowers is used for the treatment of bronchitis and cough. Crude ethanolic (70%) extract and fractions (dichloromethane, ethyl acetate and n-butanolic) were investigated regarding their toxicities in vitro and antiplatelet action. The enzyme acetylcholinesterase inhibition was evaluated to study the crude extract. The crude extract and fractions were evaluated by means of Brine Shrimp Lethality test and they showed low activities with LC(50) values 1698, 2818, 2187 and 3672 µg mL(-1) for dichloromethane, ethyl acetate, n-butanolic fractions and crude extract, respectively. Buddleja thyrsoides presented great antiplatelet action. The IC(50) values obtained for crude extract and dichloromethane, ethyl acetate and n-butanolic fractions were 361.29, 354.23, 368.75 and 344.30, respectively, while the IC(50) for the standard AAS was 257.01 µg mL(-1). The crude extract showed an inhibition of 22.8% of the acetylcholinesterase enzyme in 24 h.

  8. In Vitro Pulmonary Toxicity of Metal Oxide Nanoparticles

    DEFF Research Database (Denmark)

    Cupi, Denisa; Dreher, Kevin

    particles induced similar increases in HO-1 mRNA levels at 6hr and 24hr post-exposure, respectively. The pattern of HO-1 gene induction was inconsistent with a role of oxidative stress in metal oxide induced BEAS2B cytokine gene expression. Pretreatment of BEAS2B cells with IKK inhibitor III BMS-345541......Nanomaterials (NMs) encompass a diversity of materials with unique physicochemical characteristics which raise concerns about their potential risk to human health. Rapid predictive testing methods are needed to characterize NMs health effects as well as to screen and prioritize NMs......2B cytotoxicity was observed for any particle following a 24hr exposure to concentrations upto100 μg/ml. The ability of TiO2 and CeO2 particles to induce inflammation and oxidative stress was assessed by gene induction using RT-PCR. At 50 μg/ml maximal IL-8 and IL-6 gene induction by TiO2 and CeO2...

  9. Large Dataset of Acute Oral Toxicity Data Created for Testing ...

    Science.gov (United States)

    Acute toxicity data is a common requirement for substance registration in the US. Currently only data derived from animal tests are accepted by regulatory agencies, and the standard in vivo tests use lethality as the endpoint. Non-animal alternatives such as in silico models are being developed due to animal welfare and resource considerations. We compiled a large dataset of oral rat LD50 values to assess the predictive performance currently available in silico models. Our dataset combines LD50 values from five different sources: literature data provided by The Dow Chemical Company, REACH data from eChemportal, HSDB (Hazardous Substances Data Bank), RTECS data from Leadscope, and the training set underpinning TEST (Toxicity Estimation Software Tool). Combined these data sources yield 33848 chemical-LD50 pairs (data points), with 23475 unique data points covering 16439 compounds. The entire dataset was loaded into a chemical properties database. All of the compounds were registered in DSSTox and 59.5% have publically available structures. Compounds without a structure in DSSTox are currently having their structures registered. The structural data will be used to evaluate the predictive performance and applicable chemical domains of three QSAR models (TIMES, PROTOX, and TEST). Future work will combine the dataset with information from ToxCast assays, and using random forest modeling, assess whether ToxCast assays are useful in predicting acute oral toxicity. Pre

  10. In Vitro Toxicity of Silver Nanoparticles in Human Lung Epithelial Cells

    Science.gov (United States)

    2009-03-01

    team not only studied silver nanoparticles , but also other nanomaterials (MoO3, Al, Fe3O4, and TiO2 ). They determined through the use of MTT and LDH...the lungs diminishes quickly. Silver nanoparticles were consequently detected in the blood and other organs (heart, liver, kidney , and brain) (2008...IN VITRO TOXICITY OF SILVER NANOPARTICLES IN HUMAN LUNG EPITHELIAL CELLS THESIS Christina

  11. Hazard and risk assessment of human exposure to toxic metals using in vitro digestion assay

    Directory of Open Access Journals (Sweden)

    Hani A. Alhadrami

    2016-10-01

    Full Text Available Clean-up targets for toxic metals require that the site be “fit for purpose”. This means that targets are set with respect to defined receptors that reflect intended land-use. In this study, the likely threat of human exposure to toxic metals has been evaluated by simulating the human digestion process in vitro. The effects of key attributes (i.e. sample fraction size, pH, Kd and total metal concentrations on the bioavailability of Cu and Ni were also investigated. Total metal concentration was the key explanatory factor for Cu and Ni bioavailability. A comparative ranking of metal concentrations in the context of tolerable daily intakes for Cu and Ni confirmed that the pH has the greatest impact on metals bioavailability. Rapid screening of key attributes and total toxic metal doses can reveal the relative hazard imposed on human, and this approach should be considered when defining threshold values for human protection.

  12. Toxicological assessment of kretek cigarettes Part 4: mechanistic investigations, smoke chemistry and in vitro toxicity.

    Science.gov (United States)

    Roemer, E; Dempsey, R; Lawless-Pyne, J; Lukman, S; Evans, A Deger; Trelles-Sticken, E; Wittke, S; Schorp, M K

    2014-12-01

    The smoke chemistry and in vitro toxicity of mainstream smoke (MS) was investigated in American-blended cigarettes with or without the addition of 2.5%, 5% or 10% eugenol to the tobacco and in Indonesian-blended cigarettes with and without the addition of cloves, cloves extracted with hot ethanol, and extracted cloves replenished with eugenol or clove oil. The addition of eugenol reduced the concentration of nearly all toxicants measured in MS as well as the in vitro cytotoxicity of the gas/vapor phase. Reductions were also seen in bacterial mutagenicity of the total particulate matter (TPM) assessed by the Ames Assay. The addition of extracted cloves led to increases and decreases of toxicant concentrations in MS. Replenishment with eugenol or clove oil decreased the toxicant concentrations; with most smoke constituent concentrations reduced below the concentration found in tobacco-only cigarettes. Cytotoxicity of the TPM was not affected by the clove preparations. However, GVP cytotoxicity was reduced (untreated cloves showing the highest reductions). Mutagenicity of TPM was decreased by the clove preparations. Mechanisms for the reductions, (up to 40%), are most likely due to dilution effects by eugenol, changed burning characteristics of the tobacco, and free radical scavenging by eugenol. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Surface modification minimizes the toxicity of silver nanoparticles: an in vitro and in vivo study.

    Science.gov (United States)

    Das, Balaram; Tripathy, Satyajit; Adhikary, Jaydeep; Chattopadhyay, Sourav; Mandal, Debasis; Dash, Sandeep Kumar; Das, Sabyasachi; Dey, Aditi; Dey, Sankar Kumar; Das, Debasis; Roy, Somenath

    2017-08-01

    Currently toxicological research in Silver nanoparticle is a leading issue in medical science. The surface chemistry and physical dimensions of silver nanoparticles (Ag-NPs) play an important role in toxicity. The aim of this present study was to evaluate the in vitro and in vivo toxicity of Ag-NPs as well as the alteration of toxicity profile due to surface functionalization (PEG and BSA) and the intracellular signaling pathways involved in nanoparticles mediated oxidative stress and apoptosis in vitro and in vivo system. Ag-NPs released excess Ag+ ions leads to activation of NADPH oxidase and helps in generating the reactive oxygen species (ROS). Silver nanoparticles elicit the production of excess amount of ROS results activation of TNF-α. Ag-NPs activates caspase-3 and 9 which are the signature of mitochondrial pathway. Ag-NPs are responsible to decrease the antioxidant enzymes and imbalance the oxidative status into the cells but functionalization with BSA and PEG helps to protect the adverse effect of Ag-NPs on the cells. This study suggested that Ag-NPs are toxic to normal cells which directly lead with human health. Surface functionalization may open the gateway for further use of Ag-NPs in different area such as antimicrobial and anticancer therapy, industrial use or in biomedical sciences.

  14. Toxicity testing and chemical analyses of recycled fibre-based paper for food contact

    DEFF Research Database (Denmark)

    Binderup, Mona-Lise; Pedersen, Gitte Alsing; Vinggaard, Anne

    2002-01-01

    of different qualities as food-contact materials and to Perform a preliminary evaluation of their suitability from a safety point of view, and, second, to evaluate the use of different in vitro toxicity tests for screening of paper and board. Paper produced from three different categories of recycled fibres (B......Food-contact materials, including paper, have to comply with a basic set of criteria concerning safety. This means that paper for food contact should not give rise to migration of components, which can endanger human health. The objectives of this pilot study were, first, to compare paper...

  15. Biological test method: Acute test for sediment toxicity using marine or estuarine amphipods

    National Research Council Canada - National Science Library

    McLeay, D. J; Sprague, John B

    1992-01-01

    Methods recommended by Environment Canada for performing 10-day tests for sediment toxicity, using one or more of the following species of marine or estuarine sediment-burrowing amphipods, are described in this report...

  16. Using single-species toxicity tests, community-level responses, and toxicity identification evaluations to investigate effluent impacts

    Energy Technology Data Exchange (ETDEWEB)

    Maltby, L.; Clayton, S.A.; Yu, H.; McLoughlin, N.; Wood, R.M.; Yin, D.

    2000-01-01

    Whole effluent toxicity (WET) tests are increasingly used to monitor compliance of consented discharges, but few studies have related toxicity measured using WET tests to receiving water impacts. Here the authors adopt a four-stage procedure to investigate the toxicity and biological impact of a point source discharge and to identify the major toxicants. In stage 1, standard WET tests were employed to determine the toxicity of the effluent. This was then followed by an assessment of receiving water toxicity using in situ deployment of indigenous (Gammarus pulex) and standard (Daphnia magna) test species. The third stage involved the use of biological survey techniques to assess the impact of the discharge on the structure and functioning of the benthic macroinvertebrate community. In stage 4, toxicity identification evaluations (TIE) were used to identify toxic components in the effluent. Receiving-water toxicity and ecological impact detected downstream of the discharge were consistent with the results of WET tests performed on the effluent. Downstream of the discharge, there was a reduction in D. magna survival, in G. pulex survival and feeding rate, in detritus processing, and in biotic indices based on macroinvertebrate community structure. The TIE studies suggested that chlorine was the principal toxicant in the effluent.

  17. Intracellular localization and toxicity of graphene oxide and reduced graphene oxide nanoplatelets to mussel hemocytes in vitro.

    Science.gov (United States)

    Katsumiti, Alberto; Tomovska, Radmila; Cajaraville, Miren P

    2017-07-01

    Recently, graphene materials have attracted tremendous research interest due to their unique physicochemical properties that hold great promise in electronics, energy, materials and biomedical areas. Graphene oxide (GO) is one of the most extensively studied graphene derivatives. In order to improve GO electrical properties, nanoplatelets are chemically reduced, thus increasing nanoplatelet conductivity. This reduced GO (rGO) shows different properties and behavior compared to GO. Graphene-based wastes are expected to end up in the marine environment. Here we aimed to assess the potential toxic effects of GO and rGO to marine organisms by using in vitro assays with mussel (Mytilus galloprovincialis) hemocytes. Cells were exposed to a wide range of concentrations (up to 100mg/L) of GO (with and without polyvinylpyrrolidone-PVP as stabilizing agent: GO and GO-PVP) and rGO with PVP (rGO-PVP) to assess cytotoxicity and cell membrane integrity. Then, cells were exposed to sublethal concentrations of GO and rGO-PVP to assess their subcellular distribution through transmission electron microscopy (TEM) and to evaluate their effects on ROS production. GO, GO-PVP and rGO-PVP showed low and concentration-dependent cytotoxicity. rGO-PVP (LC50=29.902 and 33.94mg/L depending on the origin) was more toxic than GO (LC50=49.84 and 54.51mg/L depending on the origin) and GO-PVP (LC50=43.72mg/L). PVP was not toxic to hemocytes but increased bioavailability and toxicity of nanoplatelets. At TEM, GO and rGO-PVP nanoplatelets caused invaginations and perforations of the plasma membrane, which agrees with the observed decrease in cell membrane integrity. Nanoplatelets were internalized, at a higher extent for rGO-PVP than for GO, and found in the cytosol and in endolysosomal vesicles of hemocytes. Both GO and rGO-PVP increased ROS production at the highest sublethal concentration tested. In conclusion, GO, GO-PVP and rGO-PVP are not highly toxic to mussel cells but they cause membrane

  18. Sex differences in liver toxicity-do female and male human primary hepatocytes react differently to toxicants in vitro?

    Directory of Open Access Journals (Sweden)

    Milena Mennecozzi

    Full Text Available There is increasing amount of evidence for sex variation in drug efficiency and toxicity profiles. Women are more susceptible than men to acute liver injury from xenobiotics. In general, this is attributed to sex differences at a physiological level as well as differences in pharmacokinetics and pharmacodynamics, but neither of these can give a sufficient explanation for the diverse responses to xenobiotics. Existing data are mainly based on animal models and limited data exist on in vitro sex differences relevant to humans. To date, male and female human hepatocytes have not yet been compared in terms of their responses to hepatotoxic drugs. We investigated whether sex-specific differences in acute hepatotoxicity can be observed in vitro by comparing hepatotoxic drug effects in male and female primary human hepatocytes. Significant sex-related differences were found for certain parameters and individual drugs, showing an overall higher sensitivity of female primary hepatocytes to hepatotoxicants. Moreover, our work demonstrated that high content screening is feasible with pooled primary human hepatocytes in suspension.

  19. In Vitro Rat Hepatocyte Toxicity and Bacteria Genotoxicity Evaluation of High Energy Chemicals for Replacement of Hydrazine

    National Research Council Canada - National Science Library

    Husain, S

    2002-01-01

    In an effort to develop methods to predict the toxicological response of newly synthesized chemicals that are of interest to the US Air Force, in vitro rat hepatocyte toxicity and bacteria (Salmonella...

  20. In Vitro Assessment of Cadmium Bioavailability in Chinese Cabbage Grown on Different Soils and Its Toxic Effects on Human Health

    National Research Council Canada - National Science Library

    Aziz, Rukhsanda; Rafiq, Muhammad Tariq; He, Zhenli; Liu, Di; Sun, Kewang; Xiaoe, Yang

    2015-01-01

      The minimum concentration of cadmium (Cd), by Chinese cabbage grown on Cd contaminated soils that can initiate toxicity in human liver cells using in vitro digestion coupled with Caco-2/HL-7702 cell models was studied...

  1. 5-fluorouracil Toxicity Mechanism Determination in Human Keratinocytes: in vitro Study on HaCaT

    Directory of Open Access Journals (Sweden)

    Jan Hartinger

    2018-01-01

    Full Text Available 5-fluorouracil (5-FU and capecitabine therapy is often accompanied by palmar-plantar erythrodysesthesia (PPE which is manifestation of 5-FU toxicity in keratinocytes. The main mechanisms of 5-FU action are thymidylate synthase (TS inhibition which can be abrogated by thymidine and strengthened by calciumfolinate (CF and incorporation of fluorouridinetriphosphate into RNA which can be abrogated by uridine. For proper PPE treatment 5-FU mechanism of action in keratinocytes needs to be elucidated. We used the 5-FU toxicity modulators uridine, thymidine and CF to discover the mechanism of 5-FU action in human keratinocyte cell line HaCaT. To measure the cellular viability, we used MTT test and RTCA test. CF did not augment 5-FU toxicity and 5-FU toxicity was weakened by uridine. Therefore, the primary mechanism of 5-FU toxicity in keratinocytes is 5-FU incorporation into RNA. The uridine protective effect cannot fully develop in the presence of CF. Thymidine addition to 5-FU and uridine treated cells not only prevents the toxicity-augmenting CF effect but it also prolongs the 5-FU treated cells survival in comparison to uridine only. Therefore, it can be assumed that in the presence of uridine the 5-FU toxicity mechanism is switched from RNA incorporation to TS inhibition. Although particular 5-FU toxicity mechanisms were previously described in various cell types, this is the first time when various combinations of pyrimidine nucleosides and CF were used for 5-FU toxicity mechanism elucidation in human keratinocytes. We suggest that for PPE treatment ointment containing uridine and thymidine should be further clinically tested.

  2. [Modification of the Photobacterium phosphoreum toxicity test method].

    Science.gov (United States)

    Lin, Z; Yu, H; Xu, S; Wang, L

    2001-03-01

    In order to reduce the variation of Photobacterium phosphoreum luminous intensity during testing, the Photobacterium phosphoreum toxicity test was modified by a correction factor, PIacetone, in this paper. The effects of magnetic stirring time, culture time, culture generation and culture temperature on the measured results were discussed. The modified method had good laboratory repeatability and the relative standard deviation (RSD) was between 2.1% and 13.1%. Reliable data could be obtained using the modified method. It would be beneficial to the development of the quantitative structure-activity relationships on multicomponent organic compounds.

  3. Development of a Combined In Vitro Physiologically Based Kinetic (PBK) and Monte Carlo Modelling Approach to Predict Interindividual Human Variation in Phenol-Induced Developmental Toxicity.

    Science.gov (United States)

    Strikwold, Marije; Spenkelink, Bert; Woutersen, Ruud A; Rietjens, Ivonne M C M; Punt, Ans

    2017-06-01

    With our recently developed in vitro physiologically based kinetic (PBK) modelling approach, we could extrapolate in vitro toxicity data to human toxicity values applying PBK-based reverse dosimetry. Ideally information on kinetic differences among human individuals within a population should be considered. In the present study, we demonstrated a modelling approach that integrated in vitro toxicity data, PBK modelling and Monte Carlo simulations to obtain insight in interindividual human kinetic variation and derive chemical specific adjustment factors (CSAFs) for phenol-induced developmental toxicity. The present study revealed that UGT1A6 is the primary enzyme responsible for the glucuronidation of phenol in humans followed by UGT1A9. Monte Carlo simulations were performed taking into account interindividual variation in glucuronidation by these specific UGTs and in the oral absorption coefficient. Linking Monte Carlo simulations with PBK modelling, population variability in the maximum plasma concentration of phenol for the human population could be predicted. This approach provided a CSAF for interindividual variation of 2.0 which covers the 99th percentile of the population, which is lower than the default safety factor of 3.16 for interindividual human kinetic differences. Dividing the dose-response curve data obtained with in vitro PBK-based reverse dosimetry, with the CSAF provided a dose-response curve that reflects the consequences of the interindividual variability in phenol kinetics for the developmental toxicity of phenol. The strength of the presented approach is that it provides insight in the effect of interindividual variation in kinetics for phenol-induced developmental toxicity, based on only in vitro and in silico testing. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Fractionating nanosilver: importance for determining toxicity to aquatic test organisms.

    Science.gov (United States)

    Kennedy, Alan J; Hull, Matthew S; Bednar, Anthony J; Goss, Jennifer D; Gunter, Jonas C; Bouldin, Jennifer L; Vikesland, Peter J; Steevens, Jeffery A

    2010-12-15

    This investigation applied novel techniques for characterizing and fractionating nanosilver particles and aggregates and relating these measurements to toxicological endpoints. The acute toxicity of eight nanosilver suspensions of varying primary particle sizes (10-80 nm) and coatings (citrate, polyvinylpyrrolidone, EDTA, proprietary) was assessed using three aquatic test organisms (Daphnia magna, Pimephales promelas, Pseudokirchneriella subcapitata). When 48-h lethal median concentrations (LC50) were expressed as total silver, both D. magna and P. promelas were significantly more sensitive to ionic silver (Ag(+)) as AgNO(3) (mean LC50 = 1.2 and 6.3 μg/L, respectively) relative to a wide range in LC50 values determined for the nanosilver suspensions (2 -126 μg/L). However, when LC50 values for nanosilver suspensions were expressed as fractionated nanosilver (Ag(+) and/or toxicity and underscores the importance of characterizing dissolved fractions in nanometal suspensions.

  5. TRACKING PYRETHROID TOXICITY IN SURFACE WATER SAMPLES: EXPOSURE DYNAMICS AND TOXICITY IDENTIFICATION TOOLS FOR LABORATORY TESTS WITH HYALELLA AZTECA (AMPHIPODA).

    Science.gov (United States)

    Deanovic, Linda A; Stillway, Marie; Hammock, Bruce G; Fong, Stephanie; Werner, Inge

    2017-09-09

    Pyrethroid insecticides are commonly used in pest control and are present at toxic concentrations in surface waters of agricultural and urban areas worldwide. Monitoring is challenging due to their high hydrophobicity and low toxicity thresholds, which often fall below the detection limits of analytical methods. Standard daphnid bioassays used in surface water monitoring are not sensitive enough to protect more susceptible invertebrate species such as the amphipod, Hyalella azteca, and chemical loss during toxicity testing is of concern. In this study, we quantified toxicity loss during storage and testing, using both natural and synthetic water, and present a tool to enhance toxic signal strength for improved sensitivity of H. azteca toxicity tests. The average half-life during storage in LDPE cubitainers at 4°C of five pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, cyfluthrin, esfenvalerate) and one organophosphate (chlorpyrifos; used as reference) was 1.4 d, and piperonyl butoxide (PBO) proved an effective tool to potentiate toxicity. We conclude that toxicity tests on ambient water samples containing these hydrophobic insecticides are likely to underestimate toxicity present in the field, and mimic short pulse rather than continuous exposures. Where these chemicals are of concern, the addition of PBO during testing can yield valuable information on their presence or absence. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. A REVIEW OF SINGLE SPECIES TOXICITY TESTS: ARE THE TESTS RELIABLE PREDICTORS OF AQUATIC ECOSYSTEM COMMUNITY RESPONSES?

    Science.gov (United States)

    This document provides a comprehensive review to evaluate the reliability of indicator species toxicity test results in predicting aquatic ecosystem impacts, also called the ecological relevance of laboratory single species toxicity tests.

  7. Toxic effect of C60 fullerene-doxorubicin complex towards tumor and normal cells in vitro

    Directory of Open Access Journals (Sweden)

    Prylutska S. V.

    2014-09-01

    Full Text Available Creation of new nanostructures possessing high antitumor activity is an important problem of modern biotechnology. Aim. To evaluate cytotoxicity of created complex of pristine C60 fullerene with the anthracycline antibiotic doxorubicin (Dox, as well as of free C60 fullerene and Dox, towards different cell types – tumor, normal immunocompetent and hepatocytes. Methods. Measurement of size distribution for particles in C60 + Dox mixture was performed by a dynamic light scattering (DLS technique. Toxic effect of C60 + Dox complex in vitro towards tumor and normal cells was studied using the MTT assay. Results. DLS experiment demonstrated that the main fraction of the particles in C60 + Dox mixture had a diameter in the range of about 132 nm. The toxic effect of C60 + Dox complex towards normal (lymphocytes, macrophages, hepatocytes and tumor (Ehrlich ascites carcinoma, leukemia L1210, Lewis lung carcinoma cells was decreased by ~10–16 % and ~7–9 %, accordingly, compared with the same effect of free Dox. Conclusions. The created C60 + Dox composite may be considered as a new pharmacological agent that kills effectively tumor cells in vitro and simultaneously prevents a toxic effect of the free form of Dox on normal cells.

  8. Damascenine induced hepatotoxicity and nephrotoxicity in mice and in vitro assessed human erythrocyte toxicity

    Directory of Open Access Journals (Sweden)

    Bouguezza Yacine

    2015-09-01

    Full Text Available Nigella damascena seed is characterized by the presence of the major alkaloid, damascenine and its related metabolites. To our knowledge, no detailed subchronic toxicological assessment of damascenine (DA has been reported. The present study evaluated the potential toxicity of DA in vivo after sub-chronic intraperitoneal (i.p administration in mice and in vitro following human erythrocyte hemolysis. In vivo, a total of 48 adult male and female Swiss albino mice were used in a sub-chronic toxicity study. The mice received intraperitoneally two doses of DA (20 and 100 mg/kg for 28 days. Food intake, body weight and central body temperature were measured during the experiment. After completion of drug treatment, biochemical and histological analyses were performed. No mortality was observed in any of the treatment groups of mice, showing no toxic effects during the study. Neither were biochemical parameters altered; no significant differences were observed concerning glucose, bilirubin, aspartate transaminase (AST, alanine aminotransferase (ALT, urea, and creatinine parameters. No histopathological alterations were found in kidney and liver structures. In vitro, we focused on the human erythrocyte hemolytic process in the presence of several concentrations of DA. High level concentration of 1 000 μg/ml of DA revealed normal cell shapes and absence of hemolysis and deformation.

  9. [In vitro toxicity of non-preserved artificial-tear formulations].

    Science.gov (United States)

    Corrales, R M; Diebold, Y; Callejo, S; Calonge, M; Herreras, J M; Sáez, V; Mayo, A

    2001-10-01

    To analyse the putative toxic effect of three commercially available non-preserved artificial tear formulations on in vitro human conjunctival cells. A conjunctival human epithelial cell line was exposed to Cellufresh, Oculotect and Acuolens formulations during 1, 3 and 24 hours. Cytotoxicity was measured by calculating the percentage of cell viability examination and scanning electron microscopy (SEM). Controls underwent exposure to supplement free DMEM-F12 (negative control) and exposure to 0.005% benzalkonium chloride solution (positive control). Cell viability after 1 or 3 hours incubation with Cellufresh and Oculotect was similar to that obtained for negative controls. With Acuolens incubation however, cell viability showed significant reduction after 3 and 24 hours compared to control. SEM showed that Cellufresh and Oculotect exposed cells presented similar behavior to control cells. All three cell lines presented evidence of cellular surface alteration after incubation for 1 or 3 hours compared to controls, Acuolens showing the highest rate of alterations in exposed cells and an additional increment in cell loss was observed. In the present study, non preserved artificial tears formulations showed a different degree in their in vitro toxicity, Acuolens being more toxic than Cellufresh or Oculotect.

  10. Guanicid and PHMG Toxicity Tests on Aquatic Organisms

    Directory of Open Access Journals (Sweden)

    Eva Poštulková

    2016-01-01

    Full Text Available The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG. The aim of the study was to identify toxic effects of Guanicid and PHMG on zebrafish (Danio rerio and green algae (Desmodesmus communis. We determined the acute toxicity in fish according to ČSN EN ISO 7346-1, and conducted the freshwater algae growth inhibition test according to ČSN ISO 8692 methodology. For inhibition tests with green algae we chose Guanicid and PHMG concentrations of 0.001, 0.005, and 0.010 ml/L. For fish short-term acute toxicity tests we chose Guanicid concentrations of 0.010, 0.050, 0.150, 0.200, 0.250, and 0.300 ml/L and PHMG concentrations of 0.010, 0.025, 0.050, 0.075, 0.100, and 0.125 ml/L. In case of zebrafish (Danio rerio, the LC50 value for Guanicid is 0.086 ml/L, while the LC50 value for PHMG is 0.043 ml/L. Effects of Guanicid on inhibition of green algae (Desmodesmus communis appear highly significant (p < 0.010 at a concentration of 0.010 ml/L. For PHMG, these effects are highly significant (p < 0.001 at concentrations of 0.005 and 0.010 ml/L in 48 hours.

  11. Role of metabolism by intestinal bacteria in arbutin-induced toxicity in vitro.

    Science.gov (United States)

    Kang, Mi Jeong; Ha, Hyun Woo; Kim, Hyung Gyun; Lee, Dae Hun; Kong, Min Jeong; Ahn, Young Tae; Kim, Dong Hyun; Shin, Beom Soo; Kang, Wonku; Jeong, Hye Gwang; Jeong, Tae Cheon

    2011-04-01

    A possible role of metabolism by intestinal bacteria in arbutin-induced toxicity was investigated in mammalian cell cultures. Following an incubation of arbutin with intestinal bacteria, either Bifidobacterium longum HY81 or Bifidobacterium adolescentis, for 24 h, its aglycone hydroquinone could be produced and detected in the bacterial culture media. The bacterial growth was not affected up to 10 mM arbutin in the culture medium. When the toxicity of bacteria cultured medium with arbutin was tested in the HepG2 cell lines, the medium with arbutin was more toxic than either parent arbutin only or bacteria cultured medium without arbutin, indicating that metabolic activation might be required in arbutin-induced toxicity. In addition, bacteria cultured medium with arbutin could suppress LPS and ConA mitogenicity in splenocyte cultures prepared from normal mice. The results indicate that the present toxicity testing system might be applied for assessing the possible role of metabolism by intestinal bacteria in certain chemical-induced toxicity in mammalian cell cultures.

  12. The Value of In Vitro Tests to Diminish Drug Challenges

    Directory of Open Access Journals (Sweden)

    Cristobalina Mayorga

    2017-06-01

    Full Text Available Drug hypersensitivity reactions have multiple implications for patient safety and health system costs, thus it is important to perform an accurate diagnosis. The diagnostic procedure includes a detailed clinical history, often unreliable; followed by skin tests, sometimes with low sensitivity or unavailable; and drug provocation testing, which is not risk-free for the patient, especially in severe reactions. In vitro tests could help to identify correctly the responsible agent, thus improving the diagnosis of these reactions, helping the physician to find safe alternatives, and reducing the need to perform drug provocation testing. However, it is necessary to confirm the sensitivity, specificity, negative and positive predictive values for these in vitro tests to enable their implementation in clinical practice. In this review, we have analyzed these parameters from different studies that have used in vitro test for evaluating drug hypersensitivity reactions and estimated the added value of these tests to the in vivo diagnosis.

  13. Microtox solid phase test: Effect of diluent used in toxicity test.

    Science.gov (United States)

    Volpi Ghirardini, Annamaria; Girardini, Marco; Marchetto, Davide; Pantani, Claudio

    2009-03-01

    Microtox solid phase test is an acute toxicity test for solid matrices based on inhibition of natural bioluminescence of the marine bacterium Vibrio fischeri. Protocols developed to overcome the effects of confounding factors are proposed in the literature that differs by important practical and methodological issues. This work focused on diluents used for sediment resuspension and dilution. Two artificial seawaters, one natural seawater and two phosphate buffer solutions, were compared. The results showed that toxicity data obtained using different diluents were not comparable and that test sensitivity is highest using 0.1M phosphate buffer solution. The effects of medium on test organism were also investigated, in order to verify the capacity of media to maintain bioluminescence. The results underlined the importance of pH and Eh to explain the observed differences in toxicity.

  14. Human normal bronchial epithelial cells: a novel in vitro cell model for toxicity evaluation.

    Directory of Open Access Journals (Sweden)

    Wenqiang Feng

    Full Text Available Human normal cell-based systems are needed for drug discovery and toxicity evaluation. hTERT or viral genes transduced human cells are currently widely used for these studies, while these cells exhibited abnormal differentiation potential or response to biological and chemical signals. In this study, we established human normal bronchial epithelial cells (HNBEC using a defined primary epithelial cell culture medium without transduction of exogenous genes. This system may involve decreased IL-1 signaling and enhanced Wnt signaling in cells. Our data demonstrated that HNBEC exhibited a normal diploid karyotype. They formed well-defined spheres in matrigel 3D culture while cancer cells (HeLa formed disorganized aggregates. HNBEC cells possessed a normal cellular response to DNA damage and did not induce tumor formation in vivo by xenograft assays. Importantly, we assessed the potential of these cells in toxicity evaluation of the common occupational toxicants that may affect human respiratory system. Our results demonstrated that HNBEC cells are more sensitive to exposure of 10~20 nm-sized SiO2, Cr(VI and B(aP compared to 16HBE cells (a SV40-immortalized human bronchial epithelial cells. This study provides a novel in vitro human cells-based model for toxicity evaluation, may also be facilitating studies in basic cell biology, cancer biology and drug discovery.

  15. Human normal bronchial epithelial cells: a novel in vitro cell model for toxicity evaluation.

    Science.gov (United States)

    Feng, Wenqiang; Guo, Juanjuan; Huang, Haiyan; Xia, Bo; Liu, Hongya; Li, Jie; Lin, Shaolin; Li, Tiyuan; Liu, Jianjun; Li, Hui

    2015-01-01

    Human normal cell-based systems are needed for drug discovery and toxicity evaluation. hTERT or viral genes transduced human cells are currently widely used for these studies, while these cells exhibited abnormal differentiation potential or response to biological and chemical signals. In this study, we established human normal bronchial epithelial cells (HNBEC) using a defined primary epithelial cell culture medium without transduction of exogenous genes. This system may involve decreased IL-1 signaling and enhanced Wnt signaling in cells. Our data demonstrated that HNBEC exhibited a normal diploid karyotype. They formed well-defined spheres in matrigel 3D culture while cancer cells (HeLa) formed disorganized aggregates. HNBEC cells possessed a normal cellular response to DNA damage and did not induce tumor formation in vivo by xenograft assays. Importantly, we assessed the potential of these cells in toxicity evaluation of the common occupational toxicants that may affect human respiratory system. Our results demonstrated that HNBEC cells are more sensitive to exposure of 10~20 nm-sized SiO2, Cr(VI) and B(a)P compared to 16HBE cells (a SV40-immortalized human bronchial epithelial cells). This study provides a novel in vitro human cells-based model for toxicity evaluation, may also be facilitating studies in basic cell biology, cancer biology and drug discovery.

  16. Ethanol reduces amyloid aggregation in vitro and prevents toxicity in cell lines.

    Science.gov (United States)

    Ormeño, David; Romero, Fernando; López-Fenner, Julio; Avila, Andres; Martínez-Torres, Ataulfo; Parodi, Jorge

    2013-01-01

    Alzheimer's disease (AD) alters cognitive functions. A mixture of soluble β-amyloid aggregates (Aβ) are known to act as toxic agents. It has been suggested that moderate alcohol intake reduces the development of neurodegenerative diseases, but the molecular mechanisms leading to this type of prevention have been elusive. We show the ethanol effect in the generation of complex Aβ in vitro and the impact on the viability of two cell lines. The effect of ethanol on the kinetics of β-amyloid aggregation in vitro was assessed by turbimetry. Soluble- and ethanol-treated β-amyloid were added to the cell lines HEK and PC-12 to compare their effects on metabolic activity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. In addition, we used molecular modeling to assess the impact of exposure to ethanol on the structure of β-amyloid. Exposure to soluble β-amyloid was toxic to both cell lines; however, exposing the cells to β-amyloid aggregated in 10 mmol ethanol prevented the effect. In silico modeling suggested that ethanol alters the dynamics for assembling Aβ by disrupting a critical salt bridge between residues Asp 23 and Lys 28, required for amyloid dimerization. Thus, ethanol prevented the formation of complex short (∼100 nm) Aβ, which are related to higher cell toxicity. Ethanol prevents the formation of stable Aβ dimers in vitro, thus protecting the cells maintained in culture. Accordingly, in silico modelling predicts that soluble β-amyloid molecules do not form stable multimers when exposed to ethanol. Copyright © 2013 IMSS. Published by Elsevier Inc. All rights reserved.

  17. Alteration of kainic acid and quinolinic acid toxicity by neostriatal transplants in vitro.

    Science.gov (United States)

    Whetsell, W O; Allen, G S; Tulipan, N B

    1989-01-02

    Mature (greater than 21 days in vitro) organotypic corticostriatal cultures prepared from newborn rat brain were incubated in either kainic acid (KA) 10(-3) M or quinolinic acid (QUIN) 10(-3) M for up to 48 h. Other identical cultures were similarly incubated immediately after they had received one or two additional explants of neonatal striatal tissue placed beside each corticostriatal culture. The cultures incubated with either KA or QUIN in the presence of the neonatal striatal tissue showed better preservation than cultures incubated with KA or QUIN alone. Results suggest that the neonatal striatal explants or 'transplants' afford some protective effect against the toxicity or either KA or QUIN.

  18. Biofilms of vaginal Lactobacillus in vitro test.

    Science.gov (United States)

    Wei, Xiao-Yu; Zhang, Rui; Xiao, Bing-Bing; Liao, Qin-Ping

    2017-01-01

    This paper focuses on biofilms of Lactobacillus spp. - a type of normal flora isolated from healthy human vaginas of women of childbearing age; thereupon, it broadens the research scope of investigation of vaginal normal flora. The static slide culture method was adopted to foster biofilms, marked by specific fluorescence staining. Laser scanning confocal and scanning electron microscopy were used to observe the microstructure of the biofilms. Photographs taken from the microstructure were analysed to calculate the density of the biofilms. The body of Lactobacillus spp., though red, turned yellow when interacting with the green extracellular polysaccharides. The structure of the biofilm and aquaporin within the biofilm were imaged. Lactobacillus density increases over time. This study provides convincing evidence that Lactobacillus can form biofilms and grow over time in vitro. This finding establishes an important and necessary condition for selecting proper strains for the pharmaceutics of vaginal ecology.

  19. Photosynthesis tests as an alternative to growth tests for hazard assessment of toxicant

    DEFF Research Database (Denmark)

    Petersen, S.; Kusk, Kresten Ole

    2000-01-01

    Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of lightsaturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures...... limited by either nitrogen or phosphorus. The sensitivity of the photosynthesis tests were compared to standardized growth tests applied to the same species and toxicants. For Cu and S. costatum the photosynthesis test was up to 300 times more sensitive at light saturation than at light limitation....... For the remaining photosynthesis tests no dependence on light condition were found. The photosynthesis tests with Cu and S. costatum were up to 10 times as sensitive as the growth test and most sensitive when the algae were obtained from a phosphatelimited chemostate. For the other photosynthesis tests...

  20. Neurotoxicity testing: a discussion of in vitro alternatives.

    OpenAIRE

    Costa, L.G.

    1998-01-01

    A large number of chemicals may exert adverse effects on the central and/or peripheral nervous system. A commonly recommended strategy for neurotoxicity testing is that of a tiered approach aimed at identifying and characterizing the neurotoxicity of a compound. Guidelines exist in the United States and other countries that define the tests to be utilized in tier 1 testing. To address problems related to the increasing cost and time required for toxicity testing, the increasing number of chem...

  1. Development and validation of OECD test guidelines on mollusc reproductive toxicity tests

    DEFF Research Database (Denmark)

    Lagadic, Laurent; Holbech, Henrik; hutchinson, tom

    in L. stagnalis. Pre-validation tests were successful in both species. Indeed, both species could be successfully cultured at the lab. Toxicity tests provided consistent results among laboratories for each species (e.g. homogenous and nonsignificantly different NOECs, LOECs and EC 50 values for most......Validated guidelines in line with the OECD Conceptual Framework for the Testing and Assessment of Endocrine Disrupting Chemicals (EDTA) have been developed for rodents, amphibians, fish, aquatic insects and crustaceans. Only aquatic arthropods have been considered in this test battery although...... the comparison of endpoints relevant for reproduction in invertebrates often shows a much higher sensitivity in molluscs vs. e.g. daphnids. The OECD test guideline programme has thus been extended to cover reproduction effects of chemicals in molluscs. Existing mollusc toxicity test protocols have been reviewed...

  2. Evaluation of toxicity equivalent calculations for use with data from in vitro aromatase inhibition assays

    Science.gov (United States)

    With growing investment in alternatives to traditional animal toxicity tests, the next generation of risk assessment must interpret new streams of data to identify hazards and protect humans and wildlife populations. If the effects of a chemical can be characterized by a battery...

  3. Metabolic profiles show specific mitochondrial toxicities in vitro in myotube cells

    Energy Technology Data Exchange (ETDEWEB)

    Xu Qiuwei, E-mail: qiuwei_xu@merck.com; Vu, Heather; Liu Liping; Wang, Ting-Chuan; Schaefer, William H. [Merck Research Laboratories (United States)

    2011-04-15

    Mitochondrial toxicity has been a serious concern, not only in preclinical drug development but also in clinical trials. In mitochondria, there are several distinct metabolic processes including fatty acid {beta}-oxidation, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS), and each process contains discrete but often intimately linked steps. Interruption in any one of those steps can cause mitochondrial dysfunction. Detection of inhibition to OXPHOS can be complicated in vivo because intermediate endogenous metabolites can be recycled in situ or circulated systemically for metabolism in other organs or tissues. Commonly used assays for evaluating mitochondrial function are often applied to ex vivo or in vitro samples; they include various enzymatic or protein assays, as well as functional assays such as measurement of oxygen consumption rate, membrane potential, or acidification rates. Metabolomics provides quantitative profiles of overall metabolic changes that can aid in the unraveling of explicit biochemical details of mitochondrial inhibition while providing a holistic view and heuristic understanding of cellular bioenergetics. In this paper, we showed the application of quantitative NMR metabolomics to in vitro myotube cells treated with mitochondrial toxicants, rotenone and antimycin A. The close coupling of the TCA cycle to the electron transfer chain (ETC) in OXPHOS enables specific diagnoses of inhibition to ETC complexes by discrete biochemical changes in the TCA cycle.

  4. The species origin of the serum in the culture medium influences the in vitro toxicity of silica nanoparticles to HepG2 cells.

    Science.gov (United States)

    Pisani, Cédric; Rascol, Estelle; Dorandeu, Christophe; Gaillard, Jean-Charles; Charnay, Clarence; Guari, Yannick; Chopineau, Joël; Armengaud, Jean; Devoisselle, Jean-Marie; Prat, Odette

    2017-01-01

    The formation of a protein corona around nanoparticles can influence their toxicity, triggering cellular responses that may be totally different from those elicited by pristine nanoparticles. The main objective of this study was to investigate whether the species origin of the serum proteins forming the corona influences the in vitro toxicity assessment of silica nanoparticles. Coronas were preformed around nanoparticles before cell exposures by incubation in fetal bovine (FBS) or human (HS) serum. The compositions of these protein coronas were assessed by nano-LC MS/MS. The effects of these protein-coated nanoparticles on HepG2 cells were monitored using real-time cell impedance technology. The nanoparticle coronas formed in human or fetal bovine serum comprised many homologous proteins. Using human compared with fetal bovine serum, nanoparticle toxicity in HepG2 cells decreased by 4-fold and 1.5-fold, when used at 50 and 10μg/mL, respectively. It is likely that "markers of self" are present in the serum and are recognized by human cell receptors. Preforming a corona with human serum seems to be more appropriate for in vitro toxicity testing of potential nanocarriers using human cells. In vitro cytotoxicity assays must reflect in vivo conditions as closely as possible to provide solid and useful results.

  5. The species origin of the serum in the culture medium influences the in vitro toxicity of silica nanoparticles to HepG2 cells

    Science.gov (United States)

    Pisani, Cédric; Rascol, Estelle; Dorandeu, Christophe; Gaillard, Jean-Charles; Charnay, Clarence; Guari, Yannick; Chopineau, Joël; Armengaud, Jean; Devoisselle, Jean-Marie

    2017-01-01

    The formation of a protein corona around nanoparticles can influence their toxicity, triggering cellular responses that may be totally different from those elicited by pristine nanoparticles. The main objective of this study was to investigate whether the species origin of the serum proteins forming the corona influences the in vitro toxicity assessment of silica nanoparticles. Coronas were preformed around nanoparticles before cell exposures by incubation in fetal bovine (FBS) or human (HS) serum. The compositions of these protein coronas were assessed by nano-LC MS/MS. The effects of these protein-coated nanoparticles on HepG2 cells were monitored using real-time cell impedance technology. The nanoparticle coronas formed in human or fetal bovine serum comprised many homologous proteins. Using human compared with fetal bovine serum, nanoparticle toxicity in HepG2 cells decreased by 4-fold and 1.5-fold, when used at 50 and 10μg/mL, respectively. It is likely that “markers of self” are present in the serum and are recognized by human cell receptors. Preforming a corona with human serum seems to be more appropriate for in vitro toxicity testing of potential nanocarriers using human cells. In vitro cytotoxicity assays must reflect in vivo conditions as closely as possible to provide solid and useful results. PMID:28796831

  6. The species origin of the serum in the culture medium influences the in vitro toxicity of silica nanoparticles to HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Cédric Pisani

    Full Text Available The formation of a protein corona around nanoparticles can influence their toxicity, triggering cellular responses that may be totally different from those elicited by pristine nanoparticles. The main objective of this study was to investigate whether the species origin of the serum proteins forming the corona influences the in vitro toxicity assessment of silica nanoparticles. Coronas were preformed around nanoparticles before cell exposures by incubation in fetal bovine (FBS or human (HS serum. The compositions of these protein coronas were assessed by nano-LC MS/MS. The effects of these protein-coated nanoparticles on HepG2 cells were monitored using real-time cell impedance technology. The nanoparticle coronas formed in human or fetal bovine serum comprised many homologous proteins. Using human compared with fetal bovine serum, nanoparticle toxicity in HepG2 cells decreased by 4-fold and 1.5-fold, when used at 50 and 10μg/mL, respectively. It is likely that "markers of self" are present in the serum and are recognized by human cell receptors. Preforming a corona with human serum seems to be more appropriate for in vitro toxicity testing of potential nanocarriers using human cells. In vitro cytotoxicity assays must reflect in vivo conditions as closely as possible to provide solid and useful results.

  7. Role of omics techniques in the toxicity testing of nanoparticles

    Directory of Open Access Journals (Sweden)

    Eleonore Fröhlich

    2017-11-01

    Full Text Available Abstract Nanotechnology is regarded as a key technology of the twenty-first century. Despite the many advantages of nanotechnology it is also known that engineered nanoparticles (NPs may cause adverse health effects in humans. Reports on toxic effects of NPs relay mainly on conventional (phenotypic testing but studies of changes in epigenome, transcriptome, proteome, and metabolome induced by NPs have also been performed. NPs most relevant for human exposure in consumer, health and food products are metal, metal oxide and carbon-based NPs. They were also studied quite frequently with omics technologies and an overview of the study results can serve to answer the question if screening for established targets of nanotoxicity (e.g. cell death, proliferation, oxidative stress, and inflammation is sufficient or if omics techniques are needed to reveal new targets. Regulated pathways identified by omics techniques were confirmed by phenotypic assays performed in the same study and comparison of particle types and cells by the same group indicated a more cell/organ-specific than particle specific regulation pattern. Between different studies moderate overlap of the regulated pathways was observed and cell-specific regulation is less obvious. The lack of standardization in particle exposure, in omics technologies, difficulties to translate mechanistic data to phenotypes and comparison with human in vivo data currently limit the use of these technologies in the prediction of toxic effects by NPs.

  8. Metal toxicity and biodiversity in serpentine soils: application of bioassay tests and microarthropod index.

    Science.gov (United States)

    Visioli, Giovanna; Menta, Cristina; Gardi, Ciro; Conti, Federica Delia

    2013-01-01

    Eco-toxicological or bioassay tests have been intensively discussed as tools for the evaluation of soil quality. Tests using soil organisms, including microarthropods and plants, allow direct estimates to be made of important soil characteristics and functions. In this study we compared the results obtained by two in vitro standard bioassays following ISO or OECD guidelines: (i) the short term-chronic phytotoxicity germination and root elongation test using three different plant species Cucumis sativus L. (Cucurbitaceae), Lepidium sativum L. (Brassicaceae), and Medicago sativa L. (Fabaceae) and (ii) the inhibition of reproduction of Folsomia candida (Collembola) by soil pollutants to investigate the toxicity of a serpentine soil present in the Italian Apennines, rich in heavy metals such as Ni, Cr, and Co. In addition, microarthropod communities were characterised to evaluate the effects of metal contents on the soil fauna in natural conditions. Abundances, Acari/Collembola ratio, biodiversity indices and the QBS-ar index were calculated. Our results demonstrate that the two in vitro tests distinguish differences correlated with metal and organic matter contents in four sub-sites within the serpentinite. Soil fauna characterisation, not previously performed on serpentine soils, revealed differences in the most vulnerable and adapted groups of microarthropods to soil among the four sub-sites: the microarthropod community was found to be rich in term of biodiversity in the sub-site characterised by a lower metal content and a higher organic matter content and vegetation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Building a Tiered Approach to In Vitro Predictive Toxicity Screening: A Focus on Assays with In Vivo Relevance

    Science.gov (United States)

    McKim, James M

    2010-01-01

    One of the greatest challenges facing the pharmaceutical industry today is the failure of promising new drug candidates due to unanticipated adverse effects discovered during preclinical animal safety studies and clinical trials. Late stage attrition increases the time required to bring a new drug to market, inflates development costs, and represents a major source of inefficiency in the drug discovery/development process. It is generally recognized that early evaluation of new drug candidates is necessary to improve the process. Building in vitro data sets that can accurately predict adverse effects in vivo would allow compounds with high risk profiles to be deprioritized, while those that possess the requisite drug attributes and a lower risk profile are brought forward. In vitro cytotoxicity assays have been used for decades as a tool to understand hypotheses driven questions regarding mechanisms of toxicity. However, when used in a prospective manner, they have not been highly predictive of in vivo toxicity. Therefore, the issue may not be how to collect in vitro toxicity data, but rather how to translate in vitro toxicity data into meaningful in vivo effects. This review will focus on the development of an in vitro toxicity screening strategy that is based on a tiered approach to data collection combined with data interpretation. PMID:20053163

  10. Lung Toxicity of Condensed Aerosol from E-CIG Liquids: Influence of the Flavor and the In Vitro Model Used

    Directory of Open Access Journals (Sweden)

    Rossella Bengalli

    2017-10-01

    Full Text Available The diffusion of e-cigarette (e-CIG opens a great scientific and regulatory debate about its safety. The huge number of commercialized devices, e-liquids with almost infinite chemical formulations and the growing market demand for a rapid and efficient toxicity screen system that is able to test all of these references and related aerosols. A consensus on the best protocols for the e-CIG safety assessment is still far to be achieved, since the huge number of variables characterizing these products (e.g., flavoring type and concentration, nicotine concentration, type of the device, including the battery and the atomizer. This suggests that more experimental evidences are needed to support the regulatory frameworks. The present study aims to contribute in this field by testing the effects of condensed aerosols (CAs from three main e-liquid categories (tobacco, mint, and cinnamon as food-related flavor, with (18 mg/mL or without nicotine. Two in vitro models, represented by a monoculture of human epithelial alveolar cells and a three-dimensional (3D co-culture of alveolar and lung microvascular endothelial cells were used. Cell viability, pro-inflammatory cytokines release and alveolar-blood barrier (ABB integrity were investigated as inhalation toxicity endpoints. Results showed that nicotine itself had almost no influence on the modulation of the toxicity response, while flavor composition did have. The cell viability was significantly decreased in monoculture and ABB after exposure to the mints and cinnamon CAs. The barrier integrity was significantly affected in the ABB after exposure to cytotoxic CAs. With the exception of the significant IL-8 release in the monoculture after Cinnamon exposure, no increase of inflammatory cytokines (IL-8 and MCP-1 release was observed. These findings point out that multiple assays with different in vitro models are able to discriminate the acute inhalation toxicity of CAs from liquids with different flavors

  11. Comparison of the in vitro toxicity of indocyanine green to that of trypan blue in human retinal pigment epithelium cell cultures.

    Science.gov (United States)

    Gale, Jeffrey S; Proulx, Alain A; Gonder, John R; Mao, Alexander J; Hutnik, Cindy M L

    2004-07-01

    To compare the in vitro toxicity of indocyanine green (ICG) to that of trypan blue (TB) in human retinal pigment epithelium cell cultures. The use of ICG and TB in macular hole surgery is discussed. In vitro cell biology experimental study. The ICG dye and TB were applied to ARPE-19, a commercially available human retinal pigment epithelium cell line. Cultures were established and maintained according to supplier protocols. The ICG dye, TB or Hank's balanced salt solution (controls) were then applied to the cells at varying concentrations and over various exposure periods. Fiberoptic light was also applied to cells to assess for the possibility of a potentiating phototoxic effect. Cell viability fractions were determined using a well-studied mitochondrial dehydrogenase assay. The TB was not toxic to the retinal pigment epithelium cell cultures at any concentration or over any period of exposure, whereas ICG dye demonstrated dose-dependent and exposure-dependent toxicity. The ICG dye was found to be toxic to the cells at all tested concentrations between 5.0 mg/ml (stock concentration, 26.1% cell survival) and 0.5 mg/ml (92.8% cell survival) over a 3-minute exposure. No toxicity to TB was seen at the stock concentration of 1.5 mg/mL. Addition of light to the cultures did not significantly alter cell viability with either dye. Long periods of exposure, 2 hours, 24 hours, and 72 hours, to minute concentrations of either dye did not produce significant cell death. Indocyanine green demonstrates more toxicity than TB to human retinal pigment epithelium cell cultures. This is independent of any phototoxic potentiating effect of fiberoptic light or solvent toxicity. A clinically useful concentration of 0.5-mg/ml ICG causes low cytotoxicity at 3 minutes' exposure (cell survival 92.8%) and shows no detectable toxicity at 1-minute exposure (cell survival 102%).

  12. In vitro structure-toxicity relationship of chalcones in human hepatic stellate cells.

    Science.gov (United States)

    Zenger, Katharina; Dutta, Subhajit; Wolff, Horst; Genton, Marc G; Kraus, Birgit

    2015-10-02

    Xanthohumol (XN), the major prenylated chalcone from hops (Humulus lupulus L.), has received much attention within the last years, due to its multiple pharmacological activities including anti-proliferative, anti-inflammatory, antioxidant, pro-apoptotic, anti-bacterial and anti-adhesive effects. However, there exists a huge number of metabolites and structurally-related chalcones, which can be expected, or are already known, to exhibit various effects on cells. We have therefore analyzed the effects of XN and 18 other chalcones in a panel, consisting of multiple cell-based assays. Readouts of these assays addressed distinct aspects of cell-toxicity, like proliferation, mitochondrial health, cell cycle and other cellular features. Besides known active structural elements of chalcones, like the Michael system, we have identified several moieties that seem to have an impact on specific effects and toxicity in human liver cells in vitro. Based on these observations, we present a structure-toxicity model, which will be crucial to understand the molecular mechanisms of wanted effects and unwanted side-effects of chalcones. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. In vitro structure-toxicity relationship of chalcones in human hepatic stellate cells

    KAUST Repository

    Zenger, Katharina

    2015-07-19

    Xanthohumol (XN), the major prenylated chalcone from hops (Humulus lupulus L.), has received much attention within the last years, due to its multiple pharmacological activities including anti-proliferative, anti-inflammatory, antioxidant, pro-apoptotic, anti-bacterial and anti-adhesive effects. However, there exists a huge number of metabolites and structurally-related chalcones, which can be expected, or are already known, to exhibit various effects on cells. We have therefore analyzed the effects of XN and 18 other chalcones in a panel, consisting of multiple cell-based assays. Readouts of these assays addressed distinct aspects of cell-toxicity, like proliferation, mitochondrial health, cell cycle and other cellular features. Besides known active structural elements of chalcones, like the Michael system, we have identified several moieties that seem to have an impact on specific effects and toxicity in human liver cells in vitro. Based on these observations, we present a structure-toxicity model, which will be crucial to understand the molecular mechanisms of wanted effects and unwanted side-effects of chalcones.

  14. Toxicity of nanoparticles embedded in paints compared to pristine nanoparticles, in vitro study.

    Science.gov (United States)

    Smulders, Stijn; Luyts, Katrien; Brabants, Gert; Golanski, Luana; Martens, Johan; Vanoirbeek, Jeroen; Hoet, Peter H M

    2015-01-22

    The unique physicochemical properties of nanomaterials has led to an increased use in the paint and coating industry. In this study, the in vitro toxicity of three pristine ENPs (TiO2, Ag and SiO₂), three aged paints containing ENPs (TiO₂, Ag and SiO₂) and control paints without ENPs were compared. In a first experiment, cytotoxicity was assessed using a biculture consisting of human bronchial epithelial (16HBE14o-) cells and human monocytic cells (THP-1) to determine subtoxic concentrations. In a second experiment, a new coculture model of the lung-blood barrier consisting of 16HBE14o- cells, THP-1 and human lung microvascular endothelial cells (HLMVEC) was used to study pulmonary and extrapulmonary toxicity. The results show that the pristine TiO₂ and Ag ENPs have some cytotoxic effects at relative high dose, while pristine SiO₂ ENPs and all aged paints with ENPs and control paints do not. In the complex triculture model of the lung-blood barrier, no considerable changes were observed after exposure to subtoxic concentration of the different pristine ENPs and paint particles. In conclusion, we demonstrated that although pristine ENPs show some toxic effects, no significant toxicological effects were observed when they were embedded in a complex paint matrix. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Chitosan coating of copper nanoparticles reduces in vitro toxicity and increases inflammation in the lung.

    Science.gov (United States)

    Worthington, Kristan L S; Adamcakova-Dodd, Andrea; Wongrakpanich, Amaraporn; Mudunkotuwa, Imali A; Mapuskar, Kranti A; Joshi, Vijaya B; Allan Guymon, C; Spitz, Douglas R; Grassian, Vicki H; Thorne, Peter S; Salem, Aliasger K

    2013-10-04

    Despite their potential for a variety of applications, copper nanoparticles induce very strong inflammatory responses and cellular toxicity following aerosolized delivery. Coating metallic nanoparticles with polysaccharides, such as biocompatible and antimicrobial chitosan, has the potential to reduce this toxicity. In this study, copper nanoparticles were coated with chitosan using a newly developed and facile method. The presence of coating was confirmed using x-ray photoelectron spectroscopy, rhodamine tagging of chitosan followed by confocal fluorescence imaging of coated particles and observed increases in particle size and zeta potential. Further physical and chemical characteristics were evaluated using dissolution and x-ray diffraction studies. The chitosan coating was shown to significantly reduce the toxicity of copper nanoparticles after 24 and 52 h and the generation of reactive oxygen species as assayed by DHE oxidation after 24 h in vitro. Conversely, inflammatory response, measured using the number of white blood cells, total protein, and cytokines/chemokines in the bronchoalveolar fluid of mice exposed to chitosan coated versus uncoated copper nanoparticles, was shown to increase, as was the concentration of copper ions. These results suggest that coating metal nanoparticles with mucoadhesive polysaccharides (e.g. chitosan) could increase their potential for use in controlled release of copper ions to cells, but will result in a higher inflammatory response if administered via the lung.

  16. In vitro regeneration from petiole explants of non-toxic Jatropha curcas

    KAUST Repository

    Kumar, Nitish

    2011-01-01

    Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 mu M TDZ. The Induced shoot buds were transferred to MS medium containing 10 mu M kinetin (Kn), 4.5 mu M 6-benzyl aminopurine (BA), and 5.5 mu M alpha-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 mu M BA and 8.5 mu M IAA. The elongated shoots could be rooted on half-strength MS medium with 15 mu M IBA, 11.4 mu M IAA and 5.5 mu M NAA with more than 90% survival rate. (C) 2010 Elsevier B.V. All rights reserved.

  17. Chemical toxicity and radioactivity of depleted uranium: The evidence from in vivo and in vitro studies.

    Science.gov (United States)

    Asic, Adna; Kurtovic-Kozaric, Amina; Besic, Larisa; Mehinovic, Lejla; Hasic, Azra; Kozaric, Mirza; Hukic, Mirsada; Marjanovic, Damir

    2017-07-01

    The main aim of this review is to summarize and discuss the current state of knowledge on chemical toxicity and radioactivity of depleted uranium (DU) and their effect on living systems and cell lines. This was done by presenting a summary of previous investigations conducted on different mammalian body systems and cell cultures in terms of potential changes caused by either chemical toxicity or radioactivity of DU. In addition, the authors aimed to point out the limitations of those studies and possible future directions. The majority of both in vitro and in vivo studies performed using animal models regarding possible effects caused by acute or chronic DU exposure has been reviewed. Furthermore, exposure time and dose, DU particle solubility, and uranium isotopes as factors affecting the extent of DU effects have been discussed. Special attention has been dedicated to chromosomal aberrations, DNA damage and DNA breaks, as well as micronuclei formation and epigenetic changes, as DU has recently been considered a possible causative factor of all these processes. Therefore, this approach might represent a novel area of study of DU-related irradiation effects on health. Since different studies offer contradictory results, the main aim of this review is to summarize and briefly discuss previously obtained results in order to identify the current opinion on DU toxicity and radioactivity effects in relation to exposure type and duration, as well as DU properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Anesthesia Related Toxic Effects on In Vitro Fertilization Outcome: Burden of Proof

    Directory of Open Access Journals (Sweden)

    Paraskevi Matsota

    2015-01-01

    Full Text Available Management of pain and anxiety during oocyte retrieval makes anesthesia an important part of the in vitro fertilization (IVF procedures. There are many studies investigating the influence of anesthesia on IVF success. This review article provides an overview of published data regarding the potential toxic effects of different anesthetic techniques (Loco-regional, general anesthesia (GA, and monitored anesthesia care (MAC, different anesthetic agents, and alternative medicine approach (principally acupuncture on the IVF outcome. From our analysis, evidence of serious toxicity in humans is not well established. Trials regarding different anesthetic techniques ended up without clear conclusions. Studies about GA came up with conflicting results. A few trials relate GA with lower pregnancy rates, although some others failed to prove this conclusion. Furthermore, detectable amounts of some anesthetic agents are measurable in the follicular fluid but these findings are not strongly associated with toxicity. MAC and Loco-regional anesthesia appear as safe alternative choices and there is evidence of improved outcome. Whereas acupuncture may provide assistance increasing IVF success according to some trials, some others could not obtain these effects. Questions about the appropriate time of application and the underlying mechanism of action are not answered yet, so further investigation should be done.

  19. Skin Toxicity Determined In vitro by Three-Dimensional, Native-State Histoculture

    Science.gov (United States)

    Li, Lingna; Margolis, Leonid B.; Hoffman, Robert M.

    1991-03-01

    We describe a gel-supported in vitro system for culturing skin samples in a three-dimensional native state. All the cell types of skin remain viable and maintain their native architecture for at least 10 days. The culture system is used for toxicity measurements by ascertaining cell viability using two fluorescent dyes: 2',7'-bis-(2-carboxyethyl)-5-(and -6)carboxyfluorescein acetoxymethyl ester, specific for living cells, and propidium iodide, specific for dead cells. Cell staining with the dyes is measured throughout the tissue block by confocal scanning fluorescence microscopy. The dose-response to three agents--ethanol, doxorubicin, and sodium hypochlorite--is shown and, in the case of sodium hypoclorite, compared to in vivo skin toxicity with a high correlation. We also demonstrate that the end point of [^3H]thymidine incorporation measured by histological autoradiography can be used to measure toxicity. Our results with the [^3H]thymidine end point demonstrate that the hair follicle cells are the most sensitive to doxorubicin. The native-state model for skin may be an effective replacement for animal systems and superior to the dispersed skin cell systems used previously. It can allow rapid, inexpensive measurements of the effect of manufactured products, drugs, and pollutants on skin.

  20. In vitro toxicity of reuterin, a potential food biopreservative.

    Science.gov (United States)

    Fernández-Cruz, María L; Martín-Cabrejas, Izaskun; Pérez-Del Palacio, José; Gaya, Pilar; Díaz-Navarro, Caridad; Navas, José M; Medina, Margarita; Arqués, Juan L

    2016-10-01

    Reuterin has a high potential as a food preservative due to both its chemical characteristics and its antimicrobial activity against food-borne pathogens and spoilage bacteria. However, there is a lack of information about its toxicity and its capacity to interfere with the metabolism of drugs by inhibiting cytochrome P450 (CYP) activity. The results of this study indicated that reuterin exhibited a moderate cytotoxicity in the human hepatoma cell line HepG2 according to assays measuring three different endpoints in the same set of cells. Reuterin was much less toxic than acrolein and only four times more toxic than diacetyl, a generally recognized as safe flavoring compound. In vitro experiments utilizing human liver microsomes showed that reuterin presents low possibility of displaying in vivo drug interactions by inhibition of CYP3A4, CYP2D6, and CYP2C9. Therefore, reuterin can be considered a promising food biopreservative, although additional toxicology research is needed before permission for use can be granted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. In Vitro Phosphorus Solubility Test of Different Sources of Phosphorus

    OpenAIRE

    Hifizah, A

    2011-01-01

    The solubility of P from different P supplements was measured with in vitro procedures, using three different tests, which were water solubility, citric acid solubility and acid (0.1M HCl) solubility. Water solubility and citrate solubility were common tests used by the fertiliser industry and acid solubility was a new test developed to mimic conditions within the digestive tract. There were five samples used: Lomon MDCP, Duchess RP, Kynofos, meat meal and MSOP. A separate test was done with ...

  2. Acute in vitro and in vivo toxicity of a commercial grade boron nitride nanotube mixture.

    Science.gov (United States)

    Kodali, Vamsi K; Roberts, Jenny R; Shoeb, Mohammad; Wolfarth, Michael G; Bishop, Lindsey; Eye, Tracy; Barger, Mark; Roach, Katherine A; Friend, Sherri; Schwegler-Berry, Diane; Chen, Bean T; Stefaniak, Aleksandr; Jordan, Kevin C; Whitney, Roy R; Porter, Dale W; Erdely, Aaron D

    2017-10-01

    Boron nitride nanotubes (BNNTs) are an emerging engineered nanomaterial attracting significant attention due to superior electrical, chemical and thermal properties. Currently, the toxicity profile of this material is largely unknown. Commercial grade BNNTs are composed of a mixture (BNNT-M) of ∼50-60% BNNTs, and ∼40-50% impurities of boron and hexagonal boron nitride. We performed acute in vitro and in vivo studies with commercial grade BNNT-M, dispersed by sonication in vehicle, in comparison to the extensively studied multiwalled carbon nanotube-7 (MWCNT-7). THP-1 wild-type and NLRP3-deficient human monocytic cells were exposed to 0-100 µg/ml and C57BL/6 J male mice were treated with 40 µg of BNNT-M for in vitro and in vivo studies, respectively. In vitro, BNNT-M induced a dose-dependent increase in cytotoxicity and oxidative stress. This was confirmed in vivo following acute exposure increase in bronchoalveolar lavage levels of lactate dehydrogenase, pulmonary polymorphonuclear cell influx, loss in mitochondrial membrane potential and augmented levels of 4-hydroxynonenal. Uptake of this material caused lysosomal destabilization, pyroptosis and inflammasome activation, corroborated by an increase in cathepsin B, caspase 1, increased protein levels of IL-1β and IL-18 both in vitro and in vivo. Attenuation of these effects in NLRP3-deficient THP-1 cells confirmed NLRP3-dependent inflammasome activation by BNNT-M. BNNT-M induced a similar profile of inflammatory pulmonary protein production when compared to MWCNT-7. Functionally, pretreatment with BNNT-M caused suppression in bacterial uptake by THP-1 cells, an effect that was mirrored in challenged alveolar macrophages collected from exposed mice and attenuated with NLRP3 deficiency. Analysis of cytokines secreted by LPS-challenged alveolar macrophages collected after in vivo exposure to dispersions of BNNT-M showed a differential macrophage response. The observed results demonstrated acute

  3. Building-related symptoms are linked to the in vitro toxicity of indoor dust and airborne microbial propagules in schools: A cross-sectional study.

    Science.gov (United States)

    Salin, J T; Salkinoja-Salonen, M; Salin, P J; Nelo, K; Holma, T; Ohtonen, P; Syrjälä, H

    2017-04-01

    Indoor microbial toxicity is suspected to cause some building-related symptoms, but supporting epidemiological data are lacking. We examined whether the in vitro toxicity of indoor samples from school buildings was associated with work-related health symptoms (building-related symptoms, BRS). Administrators of the Helsinki City Real Estate Department selected 15 schools for the study, and a questionnaire on symptoms connected to work was sent to the teachers in the selected schools for voluntary completion. The cellular toxicity of classroom samples was determined by testing substances extracted from wiped indoor dust and by testing microbial biomass that was cultured on fallout plates. Boar sperm cells were used as indicator cells, and motility loss was the indicator for toxic effects. The effects were expressed as the half maximal effective concentration (EC50) at which >50% of the exposed boar sperm cells were immobile compared to vehicle control. Completed symptom questionnaires were received from 232 teachers [median age, 43 years; 190 (82.3%) women] with a median time of 6 years working at their school. Samples from their classrooms were available and were assessed for cellular toxicity. The Poisson regression model showed that the impact of extracts of surface-wiped school classroom dust on teacher work-related BRS was 2.8-fold (95% CI: 1.6-4.9) higher in classrooms with a toxic threshold EC50 of 6µgml-1 versus classrooms with insignificant EC50 values (EC50 >50µgml-1); Pschool classrooms with high sperm toxicity compared to less toxic sites; the RR was 1.9 (95% CI: 1.1-3.3, P=0.03) for wiped dust extracts. Teachers working in classrooms where the samples showed high sperm toxicity had more BRS. The boar sperm cell motility inhibition assay appears promising as a tool for demonstrating the presence of indoor substances associated with BRS. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Toxicity effect of Auxemma oncocalyx fraction and its active principle oncocalyxone A on in vitro culture of caprine secondary follicles and in vitro oocyte maturation

    Directory of Open Access Journals (Sweden)

    Johanna Leiva-Revilla

    2017-06-01

     abnormal chromatin configuration. There were no differences in maturation rates between the control group and DXR, A. oncocalyx and onco A treatments. In conclusion, under our culture conditions, A. oncocalyx and onco A do not exhibit a toxic effect on isolated secondary follicles and on maturation rates of COCs recovered from antral follicles, however, these drugs negatively affected the COCs viability.  Thus, the use of culture biotechnologies as an in vitro secondary follicle culture and in vitro oocyte maturation toxicity testing are appropriated methods to evaluate the possible effects of drugs in folliculogesis.

  5. High-Throughput Toxicity Testing: New Strategies for ...

    Science.gov (United States)

    In recent years, the food industry has made progress in improving safety testing methods focused on microbial contaminants in order to promote food safety. However, food industry toxicologists must also assess the safety of food-relevant chemicals including pesticides, direct additives, and food contact substances. With the rapidly growing use of new food additives, as well as innovation in food contact substance development, an interest in exploring the use of high-throughput chemical safety testing approaches has emerged. Currently, the field of toxicology is undergoing a paradigm shift in how chemical hazards can be evaluated. Since there are tens of thousands of chemicals in use, many of which have little to no hazard information and there are limited resources (namely time and money) for testing these chemicals, it is necessary to prioritize which chemicals require further safety testing to better protect human health. Advances in biochemistry and computational toxicology have paved the way for animal-free (in vitro) high-throughput screening which can characterize chemical interactions with highly specific biological processes. Screening approaches are not novel; in fact, quantitative high-throughput screening (qHTS) methods that incorporate dose-response evaluation have been widely used in the pharmaceutical industry. For toxicological evaluation and prioritization, it is the throughput as well as the cost- and time-efficient nature of qHTS that makes it

  6. Simple diagnostic tests to detect toxic alcohol intoxications.

    Science.gov (United States)

    Shin, Jai Moo; Sachs, George; Kraut, Jeffrey A

    2008-10-01

    Methanol, ethylene glycol, and diethylene glycol intoxications can produce visual disturbances, neurologic disturbances, acute renal failure, pulmonary dysfunction, cardiac dysfunction, metabolic acidosis, and death. Metabolic acidosis and an increased serum osmolality are important clues to their diagnosis. The former reflects the organic acids produced by metabolism of the parent alcohol, whereas the latter is caused by accumulation of the offending alcohol. However, neither the clinical nor the laboratory findings are specific for toxic alcohol ingestions. The definitive diagnosis of the alcohol intoxications is commonly based on detection of the alcohol or its metabolites in blood. Early diagnosis is important, because initiation of appropriate treatment can markedly decrease their rates of morbidity and mortality. Currently, detection of the parent alcohol in body fluids is inferred from its measurement in blood. This measurement is often performed by specialty laboratories using expensive equipment, and a long delay between obtaining the specimen and getting the results is not unusual. In this report, we describe liquid-based tests that detect methanol, ethylene glycol, diethylene glycol, and ethanol in saliva. The tests are sensitive, and they have different specificity for each of the alcohols facilitating distinction among them. The relatively high sensitivity and specificity of the tests as a whole will facilitate the rapid diagnosis of each of these alcohol intoxications.

  7. Towards sensible toxicity testing for nanomaterials: proposal for the specification of test design.

    Science.gov (United States)

    Potthoff, Annegret; Weil, Mirco; Meißner, Tobias; Kühnel, Dana

    2015-12-01

    During the last decade, nanomaterials (NM) were extensively tested for potential harmful effects towards humans and environmental organisms. However, a sound hazard assessment was so far hampered by uncertainties and a low comparability of test results. The reason for the low comparability is a high variation in the (1) type of NM tested with regard to raw material, size and shape and (2) procedures before and during the toxicity testing. This calls for tailored, nanomaterial-specific protocols. Here, a structured approach is proposed, intended to lead to test protocols not only tailored to specific types of nanomaterials, but also to respective test system for toxicity testing. There are existing standards on single procedures involving nanomaterials, however, not all relevant procedures are covered by standards. Hence, our approach offers a detailed way of weighting several plausible alternatives for e.g. sample preparation, in order to decide on the procedure most meaningful for a specific nanomaterial and toxicity test. A framework of several decision trees (DT) and flow charts to support testing of NM is proposed as a basis for further refinement and in-depth elaboration. DT and flow charts were drafted for (1) general procedure-physicochemical characterisation, (2) choice of test media, (3) decision on test scenario and application of NM to liquid media, (4) application of NM to the gas phase, (5) application of NM to soil and sediments, (6) dose metrics, (S1) definition of a nanomaterial, and (S2) dissolution. The applicability of the proposed approach was surveyed by using experimental data retrieved from studies on nanoscale CuO. This survey demonstrated the DT and flow charts to be a convenient tool to systematically decide upon test procedures and processes, and hence pose an important step towards harmonisation of NM testing.

  8. Reflections on a career and on the history of genetic toxicity testing in the National Toxicology Program.

    Science.gov (United States)

    Zeiger, Errol

    2017-07-01

    One of the highly visible aspects of the U.S. National Toxicology Program (NTP) has been its genetic toxicity testing program, which has been responsible for testing, and making publicly available, in vitro and in vivo test data on thousands of chemicals since 1979. What is less well known, however, is that this NTP program had its origin in two separate testing programs that were initiated independently at the National Cancer Institute (NCI) and the National Institute of Environmental Health Sciences (NIEHS) before the NTP was established. The NCI program was in response to the 1971 National Cancer Act which dramatically increased the NCI budget. In contrast, the NIEHS testing program can be traced back to a publication by Bruce Ames, not the one describing the mutagenicity assay he developed that became known as the Ames test, but because in 1975 he published an article showing that hair dyes were mutagenic. The protocols developed for these NCI contracts became the basis for the NTP Salmonella testing contracts that were awarded a few years later. These protocols, with their supporting NTP data, strongly influenced the initial in vitro OECD Test Guidelines. The background and evolution of the NTP genetic toxicity testing program is described, along with some of the more significant milestone discoveries and accomplishments from this program. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. In Vivo and In Vitro Toxicity Evaluation of Polyprenols Extracted from Ginkgo biloba L. Leaves

    Directory of Open Access Journals (Sweden)

    Cheng-Zhang Wang

    2015-12-01

    Full Text Available Polyprenols of Ginkgo biloba L. leaves (GBP are a new type of lipid with 14–24 isoprenyl units, which in humans have strong bioactivity like the dolichols. A large amount of work showed that GBP had good antibacterial activity and powerful protective effects against acute hepatic injury induced by carbon tetrachloride and alcohol, as well as antitumor activity, but the safety of GBP was not considered. The current study was designed to evaluate the toxicity of these polyprenols. Acute toxicity in mice was observed for 14 days after GBP oral dosing with 5, 7.5, 10, 15 and 21.5 g/kg body weight (b. wt. Further, an Ames toxicity assessment was carried out by plate incorporation assay on spontaneous revertant colonies of TA97, TA98, TA100 and TA102, with GBP doses designed as 8, 40, 200, 1000 and 5000 μg/dish, and subchronic toxicity was evaluated in rats for 91 days at GBP doses of 500, 1000 and 2000 mg/kg b. wt./day. The weight, food intake, hematological and biochemical indexes, the ratio of viscera/body weight, and histopathological examinations of tissue slices of organs were all investigated. The results showed that no animal behavior and appearance changes and mortality were seen during the observation period with 21.5 g/kg GBP dose in the acute toxicity test. Also, no mutagenicity effects were produced by GBP (mutation rate < 2 on the four standard Salmonella strains (p > 0.05 in the Ames toxicity test. Furthermore, the no observed adverse effect level (NOAEL of GBP was 2000 mg/kg for 91 days feeding of rats in the subchronic toxicity tests. Results also showed the hematological and biochemical indexes as well as histopathological examination changed within a small range, and all clinical observation indexes were normal. No other distinct impacts on cumulative growth of body weight, food intake and food utilization rate were discovered with GBP. No significant difference was discovered for the rats’ organ weight and the ratio of viscera

  10. 90-Day Inhalation Toxicity Study of Bio-Derived Gevo Alcohol-to-Jet (ATJ) Synthetic Paraffinic Kerosene (SPK) in Rats with Neurotoxicity Testing and Genotoxicity Assay

    Science.gov (United States)

    2015-05-31

    turned and briefly held on its back,  hind leg splay: response to being dropped approximately 30 cm (12 inches). Hind legs were painted to mark the...approximately 30 cm (12 inches). Hind legs are painted to mark the location of the hind legs upon landing. This test is not done if the animal is judged...2007. Assessing toxicity of fine and nanoparticles : Comparing in vitro measurements to in vivo pulmonary toxicity profiles. Toxicol. Sci. 97:163– 180

  11. ISDD: A computational model of particle sedimentation, diffusion and target cell dosimetry for in vitro toxicity studies

    Science.gov (United States)

    2010-01-01

    Background The difficulty of directly measuring cellular dose is a significant obstacle to application of target tissue dosimetry for nanoparticle and microparticle toxicity assessment, particularly for in vitro systems. As a consequence, the target tissue paradigm for dosimetry and hazard assessment of nanoparticles has largely been ignored in favor of using metrics of exposure (e.g. μg particle/mL culture medium, particle surface area/mL, particle number/mL). We have developed a computational model of solution particokinetics (sedimentation, diffusion) and dosimetry for non-interacting spherical particles and their agglomerates in monolayer cell culture systems. Particle transport to cells is calculated by simultaneous solution of Stokes Law (sedimentation) and the Stokes-Einstein equation (diffusion). Results The In vitro Sedimentation, Diffusion and Dosimetry model (ISDD) was tested against measured transport rates or cellular doses for multiple sizes of polystyrene spheres (20-1100 nm), 35 nm amorphous silica, and large agglomerates of 30 nm iron oxide particles. Overall, without adjusting any parameters, model predicted cellular doses were in close agreement with the experimental data, differing from as little as 5% to as much as three-fold, but in most cases approximately two-fold, within the limits of the accuracy of the measurement systems. Applying the model, we generalize the effects of particle size, particle density, agglomeration state and agglomerate characteristics on target cell dosimetry in vitro. Conclusions Our results confirm our hypothesis that for liquid-based in vitro systems, the dose-rates and target cell doses for all particles are not equal; they can vary significantly, in direct contrast to the assumption of dose-equivalency implicit in the use of mass-based media concentrations as metrics of exposure for dose-response assessment. The difference between equivalent nominal media concentration exposures on a μg/mL basis and target cell

  12. ISDD: A computational model of particle sedimentation, diffusion and target cell dosimetry for in vitro toxicity studies

    Directory of Open Access Journals (Sweden)

    Chrisler William B

    2010-11-01

    Full Text Available Abstract Background The difficulty of directly measuring cellular dose is a significant obstacle to application of target tissue dosimetry for nanoparticle and microparticle toxicity assessment, particularly for in vitro systems. As a consequence, the target tissue paradigm for dosimetry and hazard assessment of nanoparticles has largely been ignored in favor of using metrics of exposure (e.g. μg particle/mL culture medium, particle surface area/mL, particle number/mL. We have developed a computational model of solution particokinetics (sedimentation, diffusion and dosimetry for non-interacting spherical particles and their agglomerates in monolayer cell culture systems. Particle transport to cells is calculated by simultaneous solution of Stokes Law (sedimentation and the Stokes-Einstein equation (diffusion. Results The In vitro Sedimentation, Diffusion and Dosimetry model (ISDD was tested against measured transport rates or cellular doses for multiple sizes of polystyrene spheres (20-1100 nm, 35 nm amorphous silica, and large agglomerates of 30 nm iron oxide particles. Overall, without adjusting any parameters, model predicted cellular doses were in close agreement with the experimental data, differing from as little as 5% to as much as three-fold, but in most cases approximately two-fold, within the limits of the accuracy of the measurement systems. Applying the model, we generalize the effects of particle size, particle density, agglomeration state and agglomerate characteristics on target cell dosimetry in vitro. Conclusions Our results confirm our hypothesis that for liquid-based in vitro systems, the dose-rates and target cell doses for all particles are not equal; they can vary significantly, in direct contrast to the assumption of dose-equivalency implicit in the use of mass-based media concentrations as metrics of exposure for dose-response assessment. The difference between equivalent nominal media concentration exposures on a

  13. In vitro evaluation of antileishmanial activity and toxicity of essential oils of Artemisia absinthium and Echinops kebericho.

    Science.gov (United States)

    Tariku, Yinebeb; Hymete, Ariaya; Hailu, Asrat; Rohloff, Jens

    2011-04-01

    Potential toxicity, costs, and drug-resistant pathogens necessitate the development of new antileishmanial agents. Medicinal and aromatic plants constitute a major source of natural organic compounds. In this study, essential oils of Artemisia absinthium L. and Echinops kebericho Mesfin were investigated by GC and GC/MS analyses. Isolated oils were screened for antileishmanial activity against two Leishmania strains (L. aethiopica and L. donovani), and toxicity on the human monocytic leukemia (THP-1) cell line and red blood cells in vitro. GC/MS Analysis revealed 65 compounds (93.74%) for Artemisia absinthium and 43 compounds (92.85%) for Echinops kebericho oil. The oils contained the oxygenated monoterpene camphor (27.40%) and the sesquiterpene lactone dehydrocostus lactone (41.83%) as major constituents, respectively. Both oils showed activity against promastigote (MIC 0.0097-0.1565 μl/ml) and axenic amastigote forms (EC(50) 0.24-42.00 nl/ml) of both leishmania species. Weak hemolytic effect was observed for both oils, showing a slightly decreased selectivity index (SI 0.8-19.2) against the THP-1 cell line. Among the two oils tested, E. kebericho exerted strong antileishmanial activity that was even higher than that of amphotericin B with significant cytotoxicity. This study, therefore, demonstrated the potential use of both oils as source of novel agents for the treatment of leishmaniasis. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

  14. A Tox21 Approach to Altered Epigenetic Landscapes: Assessing Epigenetic Toxicity Pathways Leading to Altered Gene Expression and Oncogenic Transformation In Vitro.

    Science.gov (United States)

    Parfett, Craig L; Desaulniers, Daniel

    2017-06-01

    An emerging vision for toxicity testing in the 21st century foresees in vitro assays assuming the leading role in testing for chemical hazards, including testing for carcinogenicity. Toxicity will be determined by monitoring key steps in functionally validated molecular pathways, using tests designed to reveal chemically-induced perturbations that lead to adverse phenotypic endpoints in cultured human cells. Risk assessments would subsequently be derived from the causal in vitro endpoints and concentration vs. effect data extrapolated to human in vivo concentrations. Much direct experimental evidence now shows that disruption of epigenetic processes by chemicals is a carcinogenic mode of action that leads to altered gene functions playing causal roles in cancer initiation and progression. In assessing chemical safety, it would therefore be advantageous to consider an emerging class of carcinogens, the epigenotoxicants, with the ability to change chromatin and/or DNA marks by direct or indirect effects on the activities of enzymes (writers, erasers/editors, remodelers and readers) that convey the epigenetic information. Evidence is reviewed supporting a strategy for in vitro hazard identification of carcinogens that induce toxicity through disturbance of functional epigenetic pathways in human somatic cells, leading to inactivated tumour suppressor genes and carcinogenesis. In the context of human cell transformation models, these in vitro pathway measurements ensure high biological relevance to the apical endpoint of cancer. Four causal mechanisms participating in pathways to persistent epigenetic gene silencing were considered: covalent histone modification, nucleosome remodeling, non-coding RNA interaction and DNA methylation. Within these four interacting mechanisms, 25 epigenetic toxicity pathway components (SET1, MLL1, KDM5, G9A, SUV39H1, SETDB1, EZH2, JMJD3, CBX7, CBX8, BMI, SUZ12, HP1, MPP8, DNMT1, DNMT3A, DNMT3B, TET1, MeCP2, SETDB2, BAZ2A, UHRF1, CTCF

  15. A Tox21 Approach to Altered Epigenetic Landscapes: Assessing Epigenetic Toxicity Pathways Leading to Altered Gene Expression and Oncogenic Transformation In Vitro

    Science.gov (United States)

    Parfett, Craig L.; Desaulniers, Daniel

    2017-01-01

    An emerging vision for toxicity testing in the 21st century foresees in vitro assays assuming the leading role in testing for chemical hazards, including testing for carcinogenicity. Toxicity will be determined by monitoring key steps in functionally validated molecular pathways, using tests designed to reveal chemically-induced perturbations that lead to adverse phenotypic endpoints in cultured human cells. Risk assessments would subsequently be derived from the causal in vitro endpoints and concentration vs. effect data extrapolated to human in vivo concentrations. Much direct experimental evidence now shows that disruption of epigenetic processes by chemicals is a carcinogenic mode of action that leads to altered gene functions playing causal roles in cancer initiation and progression. In assessing chemical safety, it would therefore be advantageous to consider an emerging class of carcinogens, the epigenotoxicants, with the ability to change chromatin and/or DNA marks by direct or indirect effects on the activities of enzymes (writers, erasers/editors, remodelers and readers) that convey the epigenetic information. Evidence is reviewed supporting a strategy for in vitro hazard identification of carcinogens that induce toxicity through disturbance of functional epigenetic pathways in human somatic cells, leading to inactivated tumour suppressor genes and carcinogenesis. In the context of human cell transformation models, these in vitro pathway measurements ensure high biological relevance to the apical endpoint of cancer. Four causal mechanisms participating in pathways to persistent epigenetic gene silencing were considered: covalent histone modification, nucleosome remodeling, non-coding RNA interaction and DNA methylation. Within these four interacting mechanisms, 25 epigenetic toxicity pathway components (SET1, MLL1, KDM5, G9A, SUV39H1, SETDB1, EZH2, JMJD3, CBX7, CBX8, BMI, SUZ12, HP1, MPP8, DNMT1, DNMT3A, DNMT3B, TET1, MeCP2, SETDB2, BAZ2A, UHRF1, CTCF

  16. A Tox21 Approach to Altered Epigenetic Landscapes: Assessing Epigenetic Toxicity Pathways Leading to Altered Gene Expression and Oncogenic Transformation In Vitro

    Directory of Open Access Journals (Sweden)

    Craig L. Parfett

    2017-06-01

    Full Text Available An emerging vision for toxicity testing in the 21st century foresees in vitro assays assuming the leading role in testing for chemical hazards, including testing for carcinogenicity. Toxicity will be determined by monitoring key steps in functionally validated molecular pathways, using tests designed to reveal chemically-induced perturbations that lead to adverse phenotypic endpoints in cultured human cells. Risk assessments would subsequently be derived from the causal in vitro endpoints and concentration vs. effect data extrapolated to human in vivo concentrations. Much direct experimental evidence now shows that disruption of epigenetic processes by chemicals is a carcinogenic mode of action that leads to altered gene functions playing causal roles in cancer initiation and progression. In assessing chemical safety, it would therefore be advantageous to consider an emerging class of carcinogens, the epigenotoxicants, with the ability to change chromatin and/or DNA marks by direct or indirect effects on the activities of enzymes (writers, erasers/editors, remodelers and readers that convey the epigenetic information. Evidence is reviewed supporting a strategy for in vitro hazard identification of carcinogens that induce toxicity through disturbance of functional epigenetic pathways in human somatic cells, leading to inactivated tumour suppressor genes and carcinogenesis. In the context of human cell transformation models, these in vitro pathway measurements ensure high biological relevance to the apical endpoint of cancer. Four causal mechanisms participating in pathways to persistent epigenetic gene silencing were considered: covalent histone modification, nucleosome remodeling, non-coding RNA interaction and DNA methylation. Within these four interacting mechanisms, 25 epigenetic toxicity pathway components (SET1, MLL1, KDM5, G9A, SUV39H1, SETDB1, EZH2, JMJD3, CBX7, CBX8, BMI, SUZ12, HP1, MPP8, DNMT1, DNMT3A, DNMT3B, TET1, MeCP2, SETDB2, BAZ2

  17. In vitro red blood cell assay for oxidant toxicity of petroleum oil

    Energy Technology Data Exchange (ETDEWEB)

    Couillard, C.M.; Leighton, F.A. (Univ. of Saskatchewan, Saskatoon (Canada))

    1993-05-01

    Petroleum oil has caused hemolytic anemia in birds and mammals. In birds, an oxidant damage on circulating red cells has been identified as the primary toxic effect of ingested petroleum oils. An in vitro red blood cell assay was developed to discriminate among the oxidant activities of different petroleum oils. The assay used rabbit red blood cells with a rat liver enzyme system and formation of methemoglobin was measured as an indicator of oxidant damage to the red cells. The assay was applied to five different petroleum oils and to naphthalene, a petroleum hydrocarbon known to cause hemolytic anemia. Different petroleum oils differed in their capacity to induce methemoglobin formation. Methemoglobin levels varied from 2.9% with Arabian light crude oil to 6.2% with South Louisiana crude oil. Naphthalene induced formation of up to 37% methemoglobin. Naphthalene and the five petroleum oils generated methemoglobin only in the presence of liver enzymes.

  18. In vitro characterization and in vivo toxicity, antioxidant and immunomodulatory effect of fermented foods; Xeniji™.

    Science.gov (United States)

    Zulkawi, Noraisyah; Ng, Kam Heng; Zamberi, Rizi; Yeap, Swee Keong; Satharasinghe, Dilan; Jaganath, Indu Bala; Jamaluddin, Anisah Binti; Tan, Sheau Wei; Ho, Wan Yong; Alitheen, Noorjahan Banu; Long, Kamariah

    2017-06-30

    Xeniji, produced by fermenting various types of foods with lactic acid bacteria and yeast, has been commonly consumed as functional food. However, nutrition value, bioactivities and safety of different fermented products maybe varies. Organic acid and antioxidant profiles of Xeniji fermented foods were evaluated. Moreover, oral acute (5 g/kg body weight) and subchronic toxicity (0.1, 1 and 2 g/kg body weight) of Xeniji were tested on mice for 14 days and 30 days, respectively. Mortality, changes of body weight, organ weight and serum liver enzyme level were measured. Liver and spleen of mice from subchronic toxicity study were subjected to antioxidant and immunomodulation quantification. Xeniji was rich in β-carotene, phytonadione, polyphenol, citric acid and essential amino acids. No mortality and significant changes of body weight and serum liver enzyme level were recorded for both oral acute and subchronic toxicity studies. Antioxidant level in the liver and immunity of Xeniji treated mice were significantly upregulated in dosage dependent manner. Xeniji is a fermented functional food that rich in nutrients that enhanced antioxidant and immunity of mice. Xeniji that rich in β-carotene, phytonadione, polyphenol, citric acid and essential amino acids promote antioxidant and immunity in mice without causing toxic effect.

  19. Can interpreting sediment toxicity tests a mega sites benefit from novel approaches to normalization to address batching of tests?

    Science.gov (United States)

    Sediment toxicity tests are a key tool used in Ecological Risk Assessments for contaminated sediment sites. Interpreting test results and defining toxicity is often a challenge. This is particularly true at mega sites where the testing regime is large, and by necessity performed ...

  20. Early Evolution of the Toxicity Identification Evaluation Process: Contributions from the USEPA Effluent Testing Program

    Science.gov (United States)

    As part of its whole effluent testing program, the USEPA developed an effects-directed analysis (EDA) approach to identifying the cause of toxicity in toxic effluents or ambient waters, an EDA process termed a “Toxicity Identification Evaluation” (TIE), which is the focus of this...

  1. Toxicity of corexit 9527 and Nigerian crude oil in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    George, S.; Nelson, G.; Brooks, L. [Environmental Protection Agency, Research Triangle Park, NC (United States)] [and others

    1997-10-01

    When oil is spilled into aquatic systems, chemical dispersants frequently are applied to enhance emulsification and biological availability. In this study, toxicity of Corexit 9527 (Cx), a widely used dispersant, was evaluated with oil both in vivo and in vitro. Initially, both Cx and oil were bioassayed in a micro-suspension modification of the Salmonella reversion bioassay. Next, rats were dosed 5 weeks with oil, Cx or Cx/oil. Body and tissue weights, urine mutagenicity, and effect on intestinal enzymes and microbiota were determined. Cx (1:1000 dilution) was toxic in the bioassay and oil was negative (TA98 & TA100 +/-S9). Similar results were observed for urinary metabolites. Body and tissue weights were unaffected, but a significant reduction in small intestinal azo reductase (AR) and/or {beta}-glucuronidase (BG) was observed in animals that received Cx, oil, or Cx/oil. Effects on cecal AR were observed in the 3 treatment groups. One week nitroreductase (NR) activity was elevated, and 3 and 5 week BG activities were significantly different from controls. This correspond to an elimination of enterobacteria and enterococci in oil-treated rats and enterobacteria fluctuations in Cx- and Cx/oil-treated animals. Even though treatment of rats with Cx has no direct effect on the production of mutagenic urine metabolites from oil-treated animals, significant changes are observed in intestinal microbiota and their enzymes responsible for promutagen and procarcinogen activation.

  2. In vitro toxicity assessment of chitosan oligosaccharide coated iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Sudeep Shukla

    2015-01-01

    Full Text Available Iron oxide nanoparticles (INPs have potential biological, biomedical and environmental applications. These applications require surface modification of the iron oxide nanoparticles, which makes it non-toxic, biocompatible, stable and non-agglomerative in natural and biological surroundings. In the present study, iron oxide nanoparticles (INPs and chitosan oligosaccharide coated iron oxide nanoparticles (CSO-INPs were synthesized to evaluate the effect of surface coating on the stability and toxicity of nanoparticles. Comparative in vitro cytotoxicity of nanoparticles was evaluated in HeLa (human cervix carcinoma, A549 (human lung carcinoma and Hek293 (human embryonic kidney cells by using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay along with flow cytometry study for cell viability, membrane integrity, mitochondrial membrane potential (MMP and reactive oxygen species (ROS production. Morphological alteration in nanoparticles treated cells was analyzed by Acridine orange/ethidium bromide double staining and electron microscopy. Synthesized nanoparticles were found to be spherical in shape, well dispersed and stable at various pH values, making them suitable for biomedical and environmental applications. The present study also indicates that the chitosan oligosaccharide coating on iron oxide nanoparticles results in the decrease in cellular damage and moderate ROS production, thereby, significantly decreasing the cytotoxic impact of bare iron oxide nanoparticles.

  3. Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility test

    DEFF Research Database (Denmark)

    Nakajima, F.; Saito, K.; Isozaki, Y.

    2006-01-01

    An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road dust, into benthic organisms living in a receiving water body. The road dust is supposed to be urban runoff particles under wet weather conditions. Sodium dodecyl su...... the exposed contaminants than the traditional organic solvent extraction method and the SDS extracted fraction is applicable to toxicity tests reflecting the digestive process....

  4. Comparison of Weibull and Probit Analysis in Toxicity Testing of ...

    African Journals Online (AJOL)

    Purpose; Hunteria umbellata has been found to have therapeutic potentials in the treatments of diseases such as yaws, peptic ulcers, diabetes, piles and infertility in Nigeria; hence, the statistical analysis on the determination of acute toxicity of Hunteria umbellata was carried out in mice. Methods; Data on the acute toxicity ...

  5. Implementing Lecane quadridentata acute toxicity tests to assess the toxic effects of selected metals (Al, Fe and Zn).

    Science.gov (United States)

    Guzmán, Félix Torres; González, Francisco Javier Avelar; Martínez, Roberto Rico

    2010-03-01

    An environmental study revealed that three metals (Al, Fe and Zn) are common in the San Pedro River (SPR) (Aguascalientes, Mexico). Regrettably, in many samples the concentrations of these metals exceeded the maximum allowed toxicant concentrations levels as defined in by Mexican legislation. The highest concentrations of the three metals were found during the 2005 dry season, with elevated Al concentrations present along the entire river. Not surprisingly, the highest concentrations for all three metals came from locations adjacent to industrial areas. Estimates of the contribution of these metals to total toxicity revealed that these three metals are important contaminants of the river and responsible for most of the lethal toxicity found in environmental samples. To assess the importance of these reports, we conducted acute toxicity tests to determine LC50 for Al, Fe and Zn on the freshwater rotifer Lecane quadridentata. This permitted us to estimate the contribution of these metals to total toxicity during 2005-2006. Based on LC50 values, all three metals should be considered very toxic, with the zinc LC50 value (0.12 mg L(-1)) making it the most toxic metal for L. quadridentata. This approach can be applied to other sites with similar concentrations of these metals. (c) 2009 Elsevier Inc. All rights reserved.

  6. Toxicity in vitro of some silicon carbides and silicon nitrides: whiskers and powders.

    Science.gov (United States)

    Svensson, I; Artursson, E; Leanderson, P; Berglind, R; Lindgren, F

    1997-03-01

    The objectives of this work were to investigate the toxicity of silicon carbide whiskers and powders and silicon nitride whiskers and powders and to compare their toxicity with the toxicity of crocidolite. The effects studied were inhibition of the cloning efficiency of V79 cells, formation of DNA strand breaks by means of a nick translation assay, formation of oxygen radicals in three different assays, and the ability to stimulate neutrophils to produce hydroxyl radicals. All materials showed concentration-dependent inhibition of the cloning efficiency of V79 cells. The inhibition by the most toxic whiskers was in the same order of magnitude as that of crocidolite. Milled whiskers and powders were less toxic than the whiskers. There was a high DNA breaking potential for crocidolite and four of the silicon carbide whiskers and a rather low one for the other materials. Formation of hydroxyl radicals was found for crocidolite and one of the silicon carbide whiskers. In the neutrophil activation test, there was a great variation in the different materials' abilities to activate neutrophils. There was also a good correlation between chemiluminescence and H2O2 formation. The highest activation was found in neutrophils exposed to two of the silicon carbide whiskers and one milled whisker. The conclusion of the investigation is that some of the ceramic materials studied had damaging biological effects comparable to or greater than those of crocidolite. The results from the investigation clearly imply that caution is needed in the introduction of new ceramic fiber materials, so that the correct precautions and protective devices are used in order to avoid harm to the personnel handling the material.

  7. In vitro toxicity of polycyclic aromatic hydrocarbons and halogenated aromatic hydrocarbons to cetacean cells and tissues

    Energy Technology Data Exchange (ETDEWEB)

    Carvan, M.J. III.

    1993-01-01

    Cetaceans bioaccumulate high aromatic hydrocarbon tissue residues, and elevated levels of PCB residues in tissues are proposed to have occurred concurrently with recent epizootic deaths of dolphins. The objectives of this study were: (1) to develop and characterize an epithelial cell line derived from dolphin tissues, (2) to investigate the effects of hydrocarbon pollutants on those cells, and (3) to analyze the toxicity of hydrocarbon pollutants on cetacean tissues in vitro. An epithelial cell line, Carvan dolphin kidney (CDK), isolated from a spontaneously aborted female bottlenose dolphin, Tursiops truncatus, grew rapidly. These cells were neither transformed nor immortal. Velocity sedimentation analysis showed CDK cells contained nuclear aryl hydrocarbon receptor, suggestive of cytochrome P450 inducibility. BaP inhibited mitosis in CDK cells in a dose-dependent manner. Data indicate that CDK cells metabolize BaP, that BaP metabolites bind to cellular DNA initiating unscheduled DNA synthesis, and that the inhibition of cytochrome P450 metabolism decrease the BaP-associated inhibition of mitosis in dolphin cells. The data also suggest that TCDD acts synergistically to increase the levels of DNA damage by the procarcinogen BaP. Cetacean liver microsomes was isolated and evaluated for the presence of cytochrome P450 proteins by SDS-PAGE, apparent minimum molecular weight determination, and immunoblot analysis. P450 activity was induced in cetacean tissue samples and CDK cells by exposure in vitro to one of several cytochrome P450-inducing chemicals. The data suggest that cetacean tissues and cells can be utilized to study the in vitro induction of cytochrome P450, resultant metabolism of xenobiotic contaminants, and the subsequent cellular and molecular responses. However, the identity of specific P450 isozymes involved in this process will remain undetermined until monoclonal antibodies that recognize cetacean P450s can be generated.

  8. Protective effects and mechanisms of curcumin on podophyllotoxin toxicity in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Li, Juan; Dai, Cai-Xia; Sun, Hua [Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632 (China); Jin, Lu [Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632 (China); State Key Laboratory of New Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203 (China); Guo, Chong-Yi; Cao, Wei; Wu, Jie; Tian, Hai-Yan [Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632 (China); Luo, Cheng [State Key Laboratory of New Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203 (China); Ye, Wen-Cai [Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632 (China); Jiang, Ren-Wang, E-mail: trwjiang@jnu.edu.cn [Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632 (China)

    2012-12-01

    Podophyllotoxin (POD) is a naturally occurring lignan with pronounced antineoplastic and antiviral properties. POD binds to tubulin and prevents the formation of mitotic spindle. Although cases of overdose or accidental ingestion are quite often, no specific therapy is currently available to treat the POD intoxication. In the current investigation, the protective effects and mechanisms of curcumin (CUR) on podophyllotoxin toxicity were evaluated in vitro and in vivo. The results showed that CUR could protect POD-induced cytotoxicity by recovering the G2/M arrest and decrease the changes of membrane potential and microtubule structure in Vero cells. A significant decrease of mortality rates was observed in Swiss mice treated by intragastrical administration of POD + CUR as compared with POD alone. The POD + CUR group also exhibited decreases in plasma transaminases, alkaline phosphatase, lactate dehydrogenase, plasma urea, creatinine and malondialdehyde level but elevated superoxide dismutase and glutathione levels as compared to the POD group. Histological examination of the liver and kidney demonstrated less morphological changes in the treatment of POD + CUR as compared with POD alone. The mechanism of the protective effects might be due to the competitive binding of CUR with POD in the same colchicines binding site as revealed by the tubulin polymerization assay and the molecular docking analysis, and the antioxidant activity against the oxidative stress induced by POD. In summary, both in vitro and in vivo data indicated the promising role of CUR as a protective agent against the POD poisoning. Highlights: ► A potential antidote to treat the podophyllotoxin (POD) intoxication is found. ► Curcumin showed promising effects against POD poisoning in vitro and in vivo. ► The mechanisms lie in the antioxidant activity and competitive binding with tubulin.

  9. Comparative In Vitro Toxicity Profile of Electronic and Tobacco Cigarettes, Smokeless Tobacco and Nicotine Replacement Therapy Products: E-Liquids, Extracts and Collected Aerosols

    Directory of Open Access Journals (Sweden)

    Manoj Misra

    2014-10-01

    Full Text Available The use of electronic cigarettes (e-cigs continues to increase worldwide in parallel with accumulating information on their potential toxicity and safety. In this study, an in vitro battery of established assays was used to examine the cytotoxicity, mutagenicity, genotoxicity and inflammatory responses of certain commercial e-cigs and compared to tobacco burning cigarettes, smokeless tobacco (SLT products and a nicotine replacement therapy (NRT product. The toxicity evaluation was performed on e-liquids and pad-collected aerosols of e-cigs, pad-collected smoke condensates of tobacco cigarettes and extracts of SLT and NRT products. In all assays, exposures with e-cig liquids and collected aerosols, at the doses tested, showed no significant activity when compared to tobacco burning cigarettes. Results for the e-cigs, with and without nicotine in two evaluated flavor variants, were very similar in all assays, indicating that the presence of nicotine and flavors, at the levels tested, did not induce any cytotoxic, genotoxic or inflammatory effects. The present findings indicate that neither the e-cig liquids and collected aerosols, nor the extracts of the SLT and NRT products produce any meaningful toxic effects in four widely-applied in vitro test systems, in which the conventional cigarette smoke preparations, at comparable exposures, are markedly cytotoxic and genotoxic.

  10. Comparative in vitro toxicity profile of electronic and tobacco cigarettes, smokeless tobacco and nicotine replacement therapy products: e-liquids, extracts and collected aerosols.

    Science.gov (United States)

    Misra, Manoj; Leverette, Robert D; Cooper, Bethany T; Bennett, Melanee B; Brown, Steven E

    2014-10-30

    The use of electronic cigarettes (e-cigs) continues to increase worldwide in parallel with accumulating information on their potential toxicity and safety. In this study, an in vitro battery of established assays was used to examine the cytotoxicity, mutagenicity, genotoxicity and inflammatory responses of certain commercial e-cigs and compared to tobacco burning cigarettes, smokeless tobacco (SLT) products and a nicotine replacement therapy (NRT) product. The toxicity evaluation was performed on e-liquids and pad-collected aerosols of e-cigs, pad-collected smoke condensates of tobacco cigarettes and extracts of SLT and NRT products. In all assays, exposures with e-cig liquids and collected aerosols, at the doses tested, showed no significant activity when compared to tobacco burning cigarettes. Results for the e-cigs, with and without nicotine in two evaluated flavor variants, were very similar in all assays, indicating that the presence of nicotine and flavors, at the levels tested, did not induce any cytotoxic, genotoxic or inflammatory effects. The present findings indicate that neither the e-cig liquids and collected aerosols, nor the extracts of the SLT and NRT products produce any meaningful toxic effects in four widely-applied in vitro test systems, in which the conventional cigarette smoke preparations, at comparable exposures, are markedly cytotoxic and genotoxic.

  11. Toxic effects of tributyltin and its metabolites on harbour seal (Phoca vitulina) immune cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Frouin, Heloise [Institut National de la Recherche Scientifique - Institut Armand-Frappier, Laval, Quebec H7V 1B7 (Canada); Fisheries and Oceans Canada, Maurice Lamontagne Institute, Mont-Joli, Quebec G5H 3Z4 (Canada)], E-mail: heloise.frouin@iaf.inrs.ca; Lebeuf, Michel [Fisheries and Oceans Canada, Maurice Lamontagne Institute, Mont-Joli, Quebec G5H 3Z4 (Canada); Saint-Louis, Richard [Institut des Sciences de la Mer de Rimouski (ISMER), Universite du Quebec a Rimouski, Rimouski, Quebec G5L 3A1 (Canada); Hammill, Mike [Fisheries and Oceans Canada, Maurice Lamontagne Institute, Mont-Joli, Quebec G5H 3Z4 (Canada); Pelletier, Emilien [Institut des Sciences de la Mer de Rimouski (ISMER), Universite du Quebec a Rimouski, Rimouski, Quebec G5L 3A1 (Canada); Fournier, Michel [Institut National de la Recherche Scientifique - Institut Armand-Frappier, Laval, Quebec H7V 1B7 (Canada)

    2008-11-21

    The widespread environmental contamination, bioaccumulation and endocrine disruptor effects of butyltins (BTs) to wildlife are well documented. Although suspected, potential effects of BTs exposure on the immune system of marine mammals have been little investigated. In this study, we assessed the effects of tributyltin (TBT) and its dealkylated metabolites dibutyltin (DBT) and monobutyltin (MBT) on the immune responses of harbour seals. Peripheral blood mononuclear cells isolated from pup and adult harbour seals were exposed in vitro to varying concentrations of BTs. DBT resulted in a significant decrease at 100 and 200 nM of phagocytotic activity and reduced significantly phagocytic efficiency at 200 nM in adult seals. There was no effect in phagocytosis with TBT and MBT. In pups, the highest concentration (200 nM) of DBT inhibited phagocytic efficiency. A reduction of tumor-killing capacity of adult natural killer (NK) cells occurred when leukocytes were incubated in vitro with 50 nM DBT and 200 nM TBT for 24 h. In adult seals, T-lymphocyte proliferation was significantly suppressed when the cells were exposed to 200 nM TBT and 100 nM DBT. In pups, the proliferative response increased after an exposure to 100 nM TBT and 50 nM DBT, but decreased with 200 nM TBT and 100 nM DBT. The immune functions were more affected by BTs exposure in adults than in pups, suggesting that other unsuspected mechanisms could trigger immune parameters in pups. The toxic potential of BTs followed the order of DBT > TBT > MBT. BT concentrations of harbour seal pups from the St. Lawrence Estuary (Bic National Park) ranged between 0.1-0.4 ng Sn/g wet weight (ww) and 1.2-13.4 ng Sn/g ww in blood and blubber, respectively. For these animals, DBT concentrations were consistently below the quantification limit of 0.04 ng Sn/g ww in blood and 0.2 ng Sn/g ww in blubber. Results suggest that concentrations measured in pups are considered too low to induce toxic effects to their immune system

  12. Use of physiologically based kinetic modeling-facilitated reverse dosimetry of in vitro toxicity data for prediction of in vivo developmental toxicity of tebuconazole in rats

    NARCIS (Netherlands)

    Li, Hequn; Zhang, Mengying; Vervoort, Jacques; Rietjens, Ivonne M.C.M.; Ravenzwaay, van Bennard; Louisse, Jochem

    2017-01-01

    Toxicological hazard and risk assessment largely rely on animal testing. For economic and ethical reasons, the development and validation of reliable alternative methods for these animal studies, such as in vitro assays, are urgently needed. In vitro concentration-response curves, however, need to

  13. Development of a new integrative toxicity index based on an improvement of the sea urchin embryo toxicity test.

    Science.gov (United States)

    Morroni, L; Pinsino, A; Pellegrini, D; Regoli, F; Matranga, V

    2016-01-01

    The sea urchin embryo toxicity test is classically used to assess the noxious effects of contaminated marine waters and sediments. In Italian guidelines on quality of dredged sediments, the standard toxicity criteria used for this assay are based on a single endpoint at 48 hours of development, corresponding to the pluteus stage. Different typologies of abnormalities, including those which occur at earlier stages, are not categorized, thus preventing the evaluation of the actual teratogenic hazards. A new integrative toxicity index has been developed in this study based on the analysis of two developmental stages, at 24 and 48h post-fertilization, and the differentiation between development delays and germ layers impairments: the new toxicity index is calculated by integrating the frequency of abnormal embryos with the severity of such abnormalities. When tested on dredged sediments, the evaluation of increasing levels of toxicity affecting embryonic outcomes enhanced the capability to discriminate different samples, appearing particularly relevant to validate the sea urchin embryo toxicity assay, and supporting its utility in practical applications such as the sediments classification in harbor areas. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Development and Application of In Vitro Models for Screening Drugs and Environmental Chemicals that Predict Toxicity in Animals and Humans

    Science.gov (United States)

    Development and Application of In Vitro Models for Screening Drugs and Environmental Chemicals that Predict Toxicity in Animals and Humans (Presented by James McKim, Ph.D., DABT, Founder and Chief Science Officer, CeeTox) (5/25/2012)

  15. Aquatic toxicity testing of liquid hydrophobic chemicals – Passive dosing exactly at the saturation limit

    DEFF Research Database (Denmark)

    Stibany, Felix; Nørgaard Schmidt, Stine; Schäffer, Andreas

    2017-01-01

    inhibition tests with green algae Raphidocelis subcapitata. Growth rate inhibition at DDB solubility was 13 ± 5% (95% CI) in a first and 8 ± 3% (95% CI) in a repeated test, which demonstrated that improved exposure control can lead to good precision and repeatability of toxicity tests. This moderate toxicity......The aims of the present study were (1) to develop a passive dosing approach for aquatic toxicity testing of liquid substances with very high Kow values and (2) to apply this approach to the model substance dodecylbenzene (DDB, Log Kow = 8.65). The first step was to design a new passive dosing...... at chemical activity of unity was higher than expected relative to a reported hydrophobicity cut-off in toxicity, but lower than expected relative to a reported chemical activity range for baseline toxicity. The present study introduces a new effective approach for toxicity testing of an important group...

  16. The effect of aluminium and sodium impurities on the in vitro toxicity and pro-inflammatory potential of cristobalite

    Science.gov (United States)

    Nattrass, C.; Horwell, Claire J.; Damby, David; Brown, David; Stone, Vicki

    2017-01-01

    BackgroundExposure to crystalline silica (SiO2), in the form of quartz, tridymite or cristobalite, can cause respiratory diseases, such as silicosis. However, the observed toxicity and pathogenicity of crystalline silica is highly variable. This has been attributed to a number of inherent and external factors, including the presence of impurities. In cristobalite-rich dusts, substitutions of aluminium (Al) for silicon (Si) in the cristobalite structure, and impurities occluding the silica surface, have been hypothesised to decrease its toxicity. This hypothesis is tested here through the characterisation and in vitro toxicological study of synthesised cristobalite with incremental amounts of Al and sodium (Na) dopants. MethodsSamples of synthetic cristobalite with incremental amounts of Al and Na impurities, and tridymite, were produced through heating of a silica sol-gel. Samples were characterised for mineralogy, cristobalite purity and abundance, particle size, surface area and surface charge. In vitro assays assessed the ability of the samples to induce cytotoxicity and TNF-α production in J774 macrophages, and haemolysis of red blood cells. ResultsAl-only doped or Al+Na co-doped cristobalite contained between 1 and 4 oxide wt% Al and Na within its structure. Co-doped samples also contained Al- and Na-rich phases, such as albite. Doping reduced cytotoxicity to J774 macrophages and haemolytic capacity compared to non-doped samples. Al-only doping was more effective at decreasing cristobalite reactivity than Al+Na co-doping. The reduction in the reactivity of cristobalite is attributed to both structural impurities and a lower abundance of crystalline silica in doped samples. Neither non-doped nor doped crystalline silica induced production of the pro-inflammatory cytokine TNF-α in J774 macrophages. ConclusionsImpurities can reduce the toxic potential of cristobalite and may help explain the low reactivity of some cristobalite-rich dusts. Whilst further work

  17. The effect of aluminium and sodium impurities on the in vitro toxicity and pro-inflammatory potential of cristobalite.

    Science.gov (United States)

    Nattrass, C; Horwell, C J; Damby, D E; Brown, D; Stone, V

    2017-11-01

    Exposure to crystalline silica (SiO2), in the form of quartz, tridymite or cristobalite, can cause respiratory diseases, such as silicosis. However, the observed toxicity and pathogenicity of crystalline silica is highly variable. This has been attributed to a number of inherent and external factors, including the presence of impurities. In cristobalite-rich dusts, substitutions of aluminium (Al) for silicon (Si) in the cristobalite structure, and impurities occluding the silica surface, have been hypothesised to decrease its toxicity. This hypothesis is tested here through the characterisation and in vitro toxicological study of synthesised cristobalite with incremental amounts of Al and sodium (Na) dopants. Samples of synthetic cristobalite with incremental amounts of Al and Na impurities, and tridymite, were produced through heating of a silica sol-gel. Samples were characterised for mineralogy, cristobalite purity and abundance, particle size, surface area and surface charge. In vitro assays assessed the ability of the samples to induce cytotoxicity and TNF-α production in J774 macrophages, and haemolysis of red blood cells. Al-only doped or Al+Na co-doped cristobalite contained between 1 and 4 oxide wt% Al and Na within its structure. Co-doped samples also contained Al- and Na-rich phases, such as albite. Doping reduced cytotoxicity to J774 macrophages and haemolytic capacity compared to non-doped samples. Al-only doping was more effective at decreasing cristobalite reactivity than Al+Na co-doping. The reduction in the reactivity of cristobalite is attributed to both structural impurities and a lower abundance of crystalline silica in doped samples. Neither non-doped nor doped crystalline silica induced production of the pro-inflammatory cytokine TNF-α in J774 macrophages. Impurities can reduce the toxic potential of cristobalite and may help explain the low reactivity of some cristobalite-rich dusts. Whilst further work is required to determine if these

  18. Development of a combined in Vitro Physiologically Based Kinetic (PBK) and Monte Carlo modelling approach to predict interindividual human variation in phenol-induced developmental toxicity

    NARCIS (Netherlands)

    Strikwold, Marije; Spenkelink, Bert; Woutersen, Ruud A.; Rietjens, Ivonne M.C.M.; Punt, Ans

    2017-01-01

    With our recently developed in vitro physiologically based kinetic (PBK) modelling approach, we could extrapolate in vitro toxicity data to human toxicity values applying PBK-based reverse dosimetry. Ideally information on kinetic differences among human individuals within a population should be

  19. Toxicity test of xanthone from mangosteen on zebrafish embryos

    Science.gov (United States)

    Noordin, Muhammad Akram Mohd; Noor, Mahanem Mat; Kamaruddin, Wan Mohd Aizat Wan; Lazim, Azwan Mat; Fazry, Shazrul

    2016-11-01

    Xanthone is a chemical compound identified in mangosteen pericarp. A previous study showed that xanthone has anti-proliferating effect on cancer cells. In this study we investigate the toxicity level of xanthone in zebrafish embryo to for future reference on other animal model. We employed Fish Embryo Toxicity (FET) assay to determine the toxicity level of different concentrations of xanthone. Embryos were observed at 24, 48 and 72 hours post fertilization (hpf) under microscope at 4× magnification. The extract showed toxicity effect on embryo at concentrations of 250, 125 and 62.5 µg/mL. Concentrations at 15.63, 7.81 and 3.91 µg / mL of xanthone did not harm the embryos and showed 100% of survival.

  20. Pyrrolizidine Alkaloids: Testing for Toxic Constituents of Comfrey.

    Science.gov (United States)

    Vollmer, John J.; And Others

    1987-01-01

    Discusses the possibilities of toxins present in medicinal herbs. Describes an experiment in which toxic constituents can be selectively detected by thin-layer chromatography and NMR spectroscopy. (TW)

  1. Compound-specific effects of diverse neurodevelopmental toxicants on global gene expression in the neural embryonic stem cell test (ESTn)

    Energy Technology Data Exchange (ETDEWEB)

    Theunissen, P.T., E-mail: Peter.Theunissen@rivm.nl [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Robinson, J.F. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Pennings, J.L.A. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Herwijnen, M.H. van [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Kleinjans, J.C.S. [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Piersma, A.H. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Institute for Risk Assessment Sciences, Faculty of Veterinary Sciences, Utrecht University, Utrecht (Netherlands)

    2012-08-01

    Alternative assays for developmental toxicity testing are needed to reduce animal use in regulatory toxicology. The in vitro murine neural embryonic stem cell test (ESTn) was designed as an alternative for neurodevelopmental toxicity testing. The integration of toxicogenomic-based approaches may further increase predictivity as well as provide insight into underlying mechanisms of developmental toxicity. In the present study, we investigated concentration-dependent effects of six mechanistically diverse compounds, acetaldehyde (ACE), carbamazepine (CBZ), flusilazole (FLU), monoethylhexyl phthalate (MEHP), penicillin G (PENG) and phenytoin (PHE), on the transcriptome and neural differentiation in the ESTn. All compounds with the exception of PENG altered ESTn morphology (cytotoxicity and neural differentiation) in a concentration-dependent manner. Compound induced gene expression changes and corresponding enriched gene ontology biological processes (GO–BP) were identified after 24 h exposure at equipotent differentiation-inhibiting concentrations of the compounds. Both compound-specific and common gene expression changes were observed between subsets of tested compounds, in terms of significance, magnitude of regulation and functionality. For example, ACE, CBZ and FLU induced robust changes in number of significantly altered genes (≥ 687 genes) as well as a variety of GO–BP, as compared to MEHP, PHE and PENG (≤ 55 genes with no significant changes in GO–BP observed). Genes associated with developmentally related processes (embryonic morphogenesis, neuron differentiation, and Wnt signaling) showed diverse regulation after exposure to ACE, CBZ and FLU. In addition, gene expression and GO–BP enrichment showed concentration dependence, allowing discrimination of non-toxic versus toxic concentrations on the basis of transcriptomics. This information may be used to define adaptive versus toxic responses at the transcriptome level.

  2. Morphology-based mammalian stem cell tests reveal potential developmental toxicity of donepezil.

    Science.gov (United States)

    Lau, Caroline G Y; Marikawa, Yusuke

    2014-11-01

    Various compounds, including therapeutic drugs, can adversely impact the survival and development of embryos in the uterus. Identification of such development-interfering agents is a challenging task, although multi-angle approaches--including the use of in vitro toxicology studies involving embryonic stem cells--should alleviate some of the current difficulties. In the present study, we utilized the in vitro elongation of embryoid bodies (EBs) derived from mouse embryonal carcinoma stem cell line P19C5 as a model of early embryological events, specifically that of gastrulation and axial patterning. From our study, we identified donepezil, a medication indicated for the management of Alzheimer's disease, as a potential developmental toxicant. The extent of P19C5 EB axial elongation was diminished by donepezil in a dose-dependent manner. Although donepezil is a known inhibitor of acetylcholinesterase, interference of elongation was not mediated through this enzyme. Quantitative reverse-transcriptase PCR revealed that donepezil altered the expression pattern of a specific set of developmental regulator genes involved in patterning along the anterior-posterior body axis. When tested in mouse whole embryo culture, donepezil caused morphological abnormalities including impaired somitogenesis. Donepezil also diminished elongation morphogenesis of EBs generated from human embryonic stem cells. These results suggest that donepezil interferes with axial elongation morphogenesis of early embryos by altering the expression pattern of regulators of axial development. © 2014 Wiley Periodicals, Inc.

  3. Validation of Alternative In Vitro Methods to Animal Testing: Concepts, Challenges, Processes and Tools.

    Science.gov (United States)

    Griesinger, Claudius; Desprez, Bertrand; Coecke, Sandra; Casey, Warren; Zuang, Valérie

    This chapter explores the concepts, processes, tools and challenges relating to the validation of alternative methods for toxicity and safety testing. In general terms, validation is the process of assessing the appropriateness and usefulness of a tool for its intended purpose. Validation is routinely used in various contexts in science, technology, the manufacturing and services sectors. It serves to assess the fitness-for-purpose of devices, systems, software up to entire methodologies. In the area of toxicity testing, validation plays an indispensable role: "alternative approaches" are increasingly replacing animal models as predictive tools and it needs to be demonstrated that these novel methods are fit for purpose. Alternative approaches include in vitro test methods, non-testing approaches such as predictive computer models up to entire testing and assessment strategies composed of method suites, data sources and decision-aiding tools. Data generated with alternative approaches are ultimately used for decision-making on public health and the protection of the environment. It is therefore essential that the underlying methods and methodologies are thoroughly characterised, assessed and transparently documented through validation studies involving impartial actors. Importantly, validation serves as a filter to ensure that only test methods able to produce data that help to address legislative requirements (e.g. EU's REACH legislation) are accepted as official testing tools and, owing to the globalisation of markets, recognised on international level (e.g. through inclusion in OECD test guidelines). Since validation creates a credible and transparent evidence base on test methods, it provides a quality stamp, supporting companies developing and marketing alternative methods and creating considerable business opportunities. Validation of alternative methods is conducted through scientific studies assessing two key hypotheses, reliability and relevance of the

  4. 76 FR 38170 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2011-06-29

    ...: Kathy Calvo, Chemical Control Division (7405M), Office of Pollution Prevention and Toxics, Environmental... Toxicity to Fish. 9. Acute Toxicity to Aquatic Invertebrates. 10. Toxicity to Aquatic Plants, e.g., Algae... 0175 and 0184 Daphnia, Daphnia Static Acute, OECD 202. Acute Toxicity to Plants, 0176 and 0184 Algae...

  5. In vitro evaluation of bioremediation capacity of a commercial probiotic, Bacillus coagulans, for chromium (VI and lead (II toxicity

    Directory of Open Access Journals (Sweden)

    Pranoti Belapurkar

    2016-01-01

    Full Text Available Introduction: The bioaccumulation of heavy metals including chromium (VI (Cr (VI and lead (II (Pb (II causes fatal toxicity in humans. Some naturally occurring bacterial genera such as Bacillus and Pseudomonas help in bioremediation of these heavy metals and some of the species of Bacillus are proven probiotics. However, no study has been conducted on Bacillus coagulans, which is a proven probiotic species of genus Bacillus. Objectives: The primary objective of the present study was to assess the potential of a proven probiotic, B. coagulans, marketed as “Sporlac-DS,” to survive in the presence of Cr (VI and Pb (II and its ability to reduce its concentration in vitro. Materials and Methods: The Minimum inhibitory concentration (MIC of the organism for Cr (VI and Pb (II was determined followed by its biochemical and morphological characterization. Its antibiotic sensitivity and probiotic efficacy were assessed. Further, its bioremediation capacity was observed in vitro by determining the residual Cr (VI and Pb (II concentration after 72 h. Results: B. coagulans could tolerate up to 512 ppm concentration of Cr (VI and had an MIC of 128 ppm for Pb (II. After 72 h, the organism reduced 32 ppm Cr (VI and 64 ppm Pb (II by 93% and 89%, respectively. When B. coagulans was studied before and after growing on Cr (VI and Pb (II for 24 h, an increase was seen in sensitivity toward the tested antibiotics whereas no change was observed in morphological and biochemical characters. It also showed no change in their bile and acid tolerance, indicating that it retains its probiotic efficacy. Conclusion: The tested probiotic B. coagulans may have a potential role in bioremediation of Cr (VI and Pb (II, in vivo.

  6. Development and Evaluation of Reproductive and Developmental Toxicity Tests for Assessing the Hazards of Environmental Contaminants

    Science.gov (United States)

    1997-08-01

    place the 35 number on the dorsal surface. Five groups of 5 males were assigned to treatment groups, randomized by block design using body weights as...extracts frogs or embryos. Methods of ^^"^^t the soil for 60 to 90 days. Methods (SCFE) via earthworms or other food and^recrexposur contaminated and of...Spills 4 2. The Need for Reproductive Toxicity Testing 3. Reproductive Toxicity Assay Design 4. The Need for Developmental Toxicity Testing 5

  7. Combining in vitro embryotoxicity data with physiologically based kinetic (PBK) modelling to define in vivo dose-response curves for developmental toxicity of phenol in rat and human.

    Science.gov (United States)

    Strikwold, Marije; Spenkelink, Bert; Woutersen, Ruud A; Rietjens, Ivonne M C M; Punt, Ans

    2013-09-01

    In vitro assays are often used for the hazard characterisation of compounds, but their application for quantitative risk assessment purposes is limited. This is because in vitro assays cannot provide a complete in vivo dose-response curve from which a point of departure (PoD) for risk assessment can be derived, like the no observed adverse effect level (NOAEL) or the 95 % lower confidence limit of the benchmark dose (BMDL). To overcome this constraint, the present study combined in vitro data with a physiologically based kinetic (PBK) model applying reverse dosimetry. To this end, embryotoxicity of phenol was evaluated in vitro using the embryonic stem cell test (EST), revealing a concentration-dependent inhibition of differentiation into beating cardiomyocytes. In addition, a PBK model was developed on the basis of in vitro and in silico data and data available from the literature only. After evaluating the PBK model performance, effective concentrations (ECx) obtained with the EST served as an input for in vivo plasma concentrations in the PBK model. Applying PBK-based reverse dosimetry provided in vivo external effective dose levels (EDx) from which an in vivo dose-response curve and a PoD for risk assessment were derived. The predicted PoD lies within the variation of the NOAELs obtained from in vivo developmental toxicity data from the literature. In conclusion, the present study showed that it was possible to accurately predict a PoD for the risk assessment of phenol using in vitro toxicity data combined with reverse PBK modelling.

  8. In Vitro Evaluation of the Ophthalmic Toxicity Profile of Chlorhexidine and Propamidine Isethionate Eye Drops.

    Science.gov (United States)

    Fernández-Ferreiro, Anxo; Santiago-Varela, María; Gil-Martínez, María; González-Barcia, Miguel; Luaces-Rodríguez, Andrea; Díaz-Tome, Victoria; Pardo, María; Méndez, José Blanco; Piñeiro-Ces, Antonio; Rodríguez-Ares, María Teresa; Lamas, Maria Jesus; Otero-Espinar, Francisco J

    2017-04-01

    Acanthamoeba keratitis causes frequent epithelial lesions that fully expose the corneal stroma. The aim of this study was to determine the toxic profile of chlorhexidine and propamidine eye drops. We used primary human keratocytes in cell culture in combination with a novel technology that evaluates dynamic real-time cytotoxicity through impedance analysis. Additional studies such as a classic cell viability test (WST-1®), a bovine corneal opacity and permeability assay, and an irritation eye study (Hen's Egg Test [HET]) have been made. Both eye drop formulations showed a time- and concentration-dependent toxicity profile, in which long periods and high concentrations were more detrimental to cells. In prolonged times of exposure, propamidine is more harmful to cells than chlorhexidine. On the contrary, no irritation has been detected in using the HET-chorioallantoic membrane test and no alterations in the corneal transparency nor permeability was produced by the treatment with both eye drops. In culture assay, chlorhexidine eye drops have proven to be less cytotoxic than Brolene® for a long contact period of time, but no signs of irritation or alterations in transparency or permeability have been observed in the cornea after both treatments.

  9. Toxic Effects of Levofloxacin on Rat Annulus Fibrosus Cells: An In-vitro Study

    Science.gov (United States)

    Bai, Zhi-Long; Chen, Qian; Yang, Si-Dong; Zhang, Feng; Wang, Hai-Ying; Yang, Da-Long; Ding, Wen-Yuan

    2014-01-01

    Background Fluoroquinolones are in wide clinical use as safe and effective antibiotics. Articular cartilage, tendons, and epiphyseal growth plates have been recognized as targets of fluoroquinolone-induced connective tissue toxicity. However, the effects of fluoroquinolones on annulus fibrosus (AF) cells are still unknown. Material/Methods The main objective of this study was to investigate the effects of levofloxacin, a typical fluoroquinolone antibiotic drug, on rat AF cells in vitro. Rat annulus fibrosus (RAF) cells were treated with levofloxacin at different concentrations (0, 10, 20, 30, 40, 60, 80, and 90 μg/ml) and were assessed to determine the possible cytotoxic effects of levofloxacin. Inverted phase-contrast microscopy was used to accomplish the morphological observation of apoptosis of treated cells. Western blot and real-time quantitative RT-PCR (qPCR) was used to explore the expression of active caspase-3 and MMP-3. Flow cytometry was used to measure the apoptotic incidences. Results Our study showed that levofloxacin, with concentrations at 30, 60, and 90 μg/ml, induced dose-dependent RAF cell apoptosis and higher expression of caspase-3 and MMP-3. More apoptotic cells were observed by inverted phase-contrast microscopy. Moreover, levofloxacin increased the activity of caspase-3, and it also reduced cell viability with different concentrations ranging from 10 to 80 μg/ml. Conclusions Our study results suggest that levofloxacin has cytotoxic effects on RAF cells, characterized by enhancing apoptosis and reducing cell viability, and indicate a potential toxic effect of fluoroquinolones on RAF cells. PMID:25380657

  10. Tecoma sambucifolia: anti-inflammatory and antinociceptive activities, and 'in vitro' toxicity of extracts of the 'huarumo' of peruvian incas.

    Science.gov (United States)

    Alguacil, L F; Galán de Mera, A; Gómez, J; Llinares, F; Morales, L; Muñoz-Mingarro, M D; Pozuelo, J M; Vicente Orellana, J A

    2000-06-01

    Aqueous and alcoholic extracts of pods and flowers of Tecoma sambucifolia H.B.K. (Bignoniaceae) ('huarumo') were analysed to determine their anti-inflammatory activity (carrageenan-induced edema test), antinociceptive activity (acetic acid writhing test) and 'in vitro' toxicity in Chinese hamster ovary cells, human hepatome cells and human larynx epidermal carcinoma cells. The cytotoxic effects of both extracts were evaluated by two endpoint systems: neutral red uptake assay and tetrazolium assay. The results showed that all extracts have anti-inflammatory and antinociceptive activity, but the highest potency is that of the alcoholic extracts. There were significant differences in cytotoxicity between extracts and among the response of cells to them. The highest cytotoxicity was noted with the alcoholic extract, and the human hepatome cell line was the most sensitive, especially to the alcoholic extract of flowers. The aqueous pod extract appeared to have the best pharmaco-toxicological profile, since it provided a significant reduction of both pain and inflammation together with the lowest cytotoxicity.

  11. Standardized toxicity testing may underestimate ecotoxicity: Environmentally relevant food rations increase the toxicity of silver nanoparticles to Daphnia.

    Science.gov (United States)

    Stevenson, Louise M; Krattenmaker, Katherine E; Johnson, Erica; Bowers, Alexandra J; Adeleye, Adeyemi S; McCauley, Edward; Nisbet, Roger M

    2017-11-01

    Daphnia in the natural environment experience fluctuations in algal food supply, with periods when algal populations bloom and seasons when Daphnia have very little algal food. Standardized chronic toxicity tests, used for ecological risk assessment, dictate that Daphnia must be fed up to 400 times more food than they would experience in the natural environment (outside of algal blooms) for a toxicity test to be valid. This disconnect can lead to underestimating the toxicity of a contaminant. We followed the growth, reproduction, and survival of Daphnia exposed to 75 and 200 µg/L silver nanoparticles (AgNPs) at 4 food rations for up to 99 d and found that AgNP exposure at low, environmentally relevant food rations increased the toxicity of AgNPs. Exposure to AgNP at low food rations decreased the survival and/or reproduction of individuals, with potential consequences for Daphnia populations (based on calculated specific population growth rates). We also found tentative evidence that a sublethal concentration of AgNPs (75 µg/L) caused Daphnia to alter energy allocation away from reproduction and toward survival and growth. The present findings emphasize the need to consider resource availability, and not just exposure, in the environment when estimating the effect of a toxicant. Environ Toxicol Chem 2017;36:3008-3018. © 2017 SETAC. © 2017 SETAC.

  12. Improving toxicity assessment of pesticide mixtures: the use of polar passive sampling devices extracts in microalgae toxicity tests

    Directory of Open Access Journals (Sweden)

    Sandra KIM TIAM

    2016-09-01

    Full Text Available Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively aimed i at characterizing the toxic potential of waters using dose-response curves, and ii at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed.

  13. Improving Toxicity Assessment of Pesticide Mixtures: The Use of Polar Passive Sampling Devices Extracts in Microalgae Toxicity Tests.

    Science.gov (United States)

    Kim Tiam, Sandra; Fauvelle, Vincent; Morin, Soizic; Mazzella, Nicolas

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the "toxic potential" of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed.

  14. In Vitro Endothelialization Test of Biomaterials Using Immortalized Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Ken Kono

    Full Text Available Functionalizing biomaterials with peptides or polymers that enhance recruitment of endothelial cells (ECs can reduce blood coagulation and thrombosis. To assess endothelialization of materials in vitro, primary ECs are generally used, although the characteristics of these cells vary among the donors and change with time in culture. Recently, primary cell lines immortalized by transduction of simian vacuolating virus 40 large T antigen or human telomerase reverse transcriptase have been developed. To determine whether immortalized ECs can substitute for primary ECs in material testing, we investigated endothelialization on biocompatible polymers using three lots of primary human umbilical vein endothelial cells (HUVEC and immortalized microvascular ECs, TIME-GFP. Attachment to and growth on polymer surfaces were comparable between cell types, but results were more consistent with TIME-GFP. Our findings indicate that TIME-GFP is more suitable for in vitro endothelialization testing of biomaterials.

  15. Anodonta imbecillis copper sulfate reference toxicant test, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12-21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained in a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values.

  16. Significance of Intratracheal Instillation Tests for the Screening of Pulmonary Toxicity of Nanomaterials.

    Science.gov (United States)

    Morimoto, Yasuo; Izumi, Hiroto; Yoshiura, Yukiko; Fujisawa, Yuri; Fujita, Katsuhide

    Inhalation tests are the gold standard test for the estimation of the pulmonary toxicity of respirable materials. Intratracheal instillation tests have been used widely, but they yield limited evidence of the harmful effects of respirable materials. We reviewed the effectiveness of intratracheal instillation tests for estimating the hazards of nanomaterials, mainly using research papers featuring intratracheal instillation and inhalation tests centered on a Japanese national project. Compared to inhalation tests, intratracheal instillation tests induced more acute inflammatory responses in the animal lung due to a bolus effect regardless of the toxicity of the nanomaterials. However, nanomaterials with high toxicity induced persistent inflammation in the chronic phase, and nanomaterials with low toxicity induced only transient inflammation. Therefore, in order to estimate the harmful effects of a nanomaterial, an observation period of 3 months or 6 months following intratracheal instillation is necessary. Among the endpoints of pulmonary toxicity, cell count and percentage of neutrophil, chemokines for neutrophils and macrophages, and oxidative stress markers are considered most important. These markers show persistent and transient responses in the lung from nanomaterials with high and low toxicity, respectively. If the evaluation of the pulmonary toxicity of nanomaterials is performed in not only the acute but also the chronic phase in order to avoid the bolus effect of intratracheal instillation and inflammatory-related factors that are used as endpoints of pulmonary toxicity, we speculate that intratracheal instillation tests can be useful for screening for the identification of the hazard of nanomaterials through pulmonary inflammation.

  17. Alternative approaches for identifying acute systemic toxicity : Moving from research to regulatory testing

    NARCIS (Netherlands)

    Hamm, Jon; Sullivan, Kristie; Clippinger, Amy J; Strickland, Judy; Bell, Shannon; Bhhatarai, Barun; Blaauboer, B|info:eu-repo/dai/nl/068359802; Casey, Warren; Dorman, David; Forsby, Anna; Garcia-Reyero, Natàlia; Gehen, Sean; Graepel, Rabea; Hotchkiss, Jon; Lowit, Anna; Matheson, Joanna; Reaves, Elissa; Scarano, Louis; Sprankle, Catherine; Tunkel, Jay; Wilson, Dan; Xia, Menghang; Zhu, Hao; Allen, David

    Acute systemic toxicity testing provides the basis for hazard labeling and risk management of chemicals. A number of international efforts have been directed at identifying non-animal alternatives for in vivo acute systemic toxicity tests. A September 2015 workshop, Alternative Approaches for

  18. Population growth rate determinants for Arbacia: Evaluating ecological relevance of toxicity test endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Nacci, D.; Gleason, T.; Munns, W.R. Jr. [Environmental Protection Agency, Narragansett, RI (United States). Environmental Research Lab.

    1995-12-31

    A population dynamics model for the sea urchin, Arbacia punctulata, was recently developed incorporating life stage endpoints frequently measured in acute and chronic toxicity studies. Model elasticity analysis was used to demonstrate that population growth rate was influenced most by adult survival and least by early life stage success, calling into question the ecological relevance of results from standardized Arbacia fertilization and larval development toxicity tests. Two approaches were used to continue this evaluation. Actual and hypothetical dose-response curves for toxicant exposures over multiple life stages were used to evaluate contributions to population growth rate of stage-specific toxicant effects. Additionally, relationships between critical life stages were developed from laboratory data for Arbacia. The results of this analysis underscore the importance of understanding both endpoint sensitivity to toxicants and sensitivity of population growth rate to test endpoints in determining the ecological relevance of toxicity tests results.

  19. ISDD: A Computational Model of Particle Sedimentation, Diffusion and Target Cell Dosimetry for In Vitro Toxicity Studies

    Energy Technology Data Exchange (ETDEWEB)

    Hinderliter, Paul M.; Minard, Kevin R.; Orr, Galya; Chrisler, William B.; Thrall, Brian D.; Pounds, Joel G.; Teeguarden, Justin G.

    2010-11-30

    Background: The difficulty of directly measuring cellular dose is a significant obstacle to application of target tissue dosimetry for nanoparticle and microparticle toxicity assessment. As a consequence, the target tissue paradigm for dosimetry and hazard assessment of nanoparticles has largely been ignored in favor of using metrics of exposure (e.g. μg particle/mL culture medium, particle surface area/mL, particle number/mL). We have developed a computational model of solution particokinetics (sedimentation, diffusion) and dosimetry for non-interacting spherical particles and their agglomerates in monolayer cell culture systems. Particle transport to cells is calculated by simultaneous solution of Stokes Law (sedimentation) and the Stokes-Einstein equation (diffusion). Results: The In vitro Sedimentation, Diffusion and Dosimetry model (ISDD) was tested against measured transport rates or cellular doses for multiple sizes of polystyrene spheres (20-1100 nm), 35 nm amorphous silica, and large agglomerates of 30 nm iron oxide particles. Overall, without adjusting any parameters, model predicted doses were in close agreement with the experimental data, differing from as little as 5% to as much as three-fold, but in most cases approximately two-fold, within the limits of the accuracy of the measurement systems. Applying the model, we generalize the effects of particle size, particle density, agglomeration state and agglomerate characteristics on target cell dosimetry in vitro. Conclusions: Our results confirm our hypothesis that the dose-rates for all particles are not equal, but can vary significantly, in direct contrast to the assumption of dose-equivalency implicit in the use of mass-based media concentrations as metrics of exposure for dose-response assessment. The difference between equivalent nominal media concentration exposures on a μg/mL basis and target cell doses on a particle surface area or number basis can be as high as three to six orders of magnitude

  20. In vitro Protoscolicidal Effects of Cinnamomum zeylanicum Essential Oil and Its Toxicity in Mice

    Science.gov (United States)

    Mahmoudvand, Hossein; Mahmoudvand, Hormoz; Oliaee, Razieh Tavakoli; Kareshk, Amir Tavakoli; Mirbadie, Seyed Reza; Aflatoonian, Mohammad Reza

    2017-01-01

    Background: This study investigates the scolicidal effects of Cinnamomum zeylanicum essential oil against the protoscoleces of hydatid cysts and its toxicity in the mice model. Materials and Methods: Gas chromatography/mass spectroscopy analyses were used to identify the constituents of essential oil. Protoscoleces were treated with different concentrations of the essential oil (6.25–100 µL/mL) in each test tube for 5–30 min. The viability of protoscoleces was confirmed using eosin exclusion test (0.1% eosin staining). Forty-eight male NMRI mice were also used to determine the toxicity of C. zeylanicum essential oil (0.5–4 mL/kg). Results: The main components were found to be cinnamaldehyde (91.8%), ρ metoxicinamate (1.57%), and α pinene (1.25%). Findings indicate that C. zeylanicum essential oil with the concentrations of 100 and 50 µL/mL killed 100% of protoscoleces after 5 min of exposure. Also, the lower concentrations of C. zeylanicum essential oil motivated a late protoscolicidal effect. The LD50 value of intraperitoneal injection of C. zeylanicum essential oil was 2.07 mL/kg body weight after 48 h, and the maximum nonfatal dose was 1.52 mL/kg body weight. The results also showed that there was no significant toxicity following oral administration of C. zeylanicum essential oil for 2 weeks. Conclusion: The results exhibited the favorable scolicidal activity of C. zeylanicum, which could be applied as a natural scolicidal agent in hydatid cyst surgery. SUMMARY We evaluated the efficacy of Cinnamomum zeylanicum essential oil against hydatid cyst protoscolecesThe viability of protoscoleces was confirmed using eosin exclusion test (0.1% eosin staining)Forty-eight male NMRI mice were also used to determine the toxicity of C. zeylanicum essential oilC. zeylanicum with potent scolicidal activity could be applied as a natural scolicidal agent in surgery. Abbreviations used: GC/MS: Gas chromatography/mass spectrometry analysis; CE: Cystic echinococcosis; LD

  1. Development and application of a marine sediment porewater toxicity test using algal spores

    Energy Technology Data Exchange (ETDEWEB)

    Hooten, R. [Texas A and M Univ., Corpus Christi, TX (United States); Carr, R.S. [National Biological Service, Corpus Christi, TX (United States)

    1995-12-31

    An acute pore water toxicity test protocol using germination and growth of marine macroalgae as endpoints was developed to indicate the presence of toxic compounds in marine/estuarine and sediment porewater samples. Zoospores collected from Ulva fasciata and U. lactuca were used as test organisms. Preliminary results with sodium dodecyl sulfate (SDS, a reference toxicant) indicate that zoospores germination and growth of embryonic gametophytes are as sensitive as the sea urchin fertilization and embryological development toxicity tests. Algal germination and growth data for copper, mercury and other metals will be presented. The results of tests utilizing this algal assay with sediment pore water from contaminated sediments will be compared with more traditional sediment toxicity test methods.

  2. In vivo and in vitro toxicity of nanogold conjugated snake venom protein toxin GNP-NKCT1

    Directory of Open Access Journals (Sweden)

    Partha Pratim Saha

    2014-01-01

    Full Text Available Research on nanoparticles has created interest among the biomedical scientists. Nanoparticle conjugation aims to target drug delivery, increase drug efficacy and imaging for better diagnosis. Toxicity profile of the nanoconjugated molecules has not been studied well. In this communication, the toxicity profile of snake venom cytotoxin (NKCT1, an antileukemic protein toxin, was evaluated after its conjugation with gold nanoparticle (GNP-NKCT1. Gold nanoparticle conjugation with NKCT1 was done with NaBH4 reduction method. The conjugated product GNP-NKCT1 was found less toxic than NKCT1 on isolated rat lymphocyte, mice peritoneal macrophage, in culture, which was evident from the MTT/Trypan blue assay. Peritoneal mast cell degranulation was in the order of NKCT1 > GNP-NKCT1. The in vitro cardiotoxicity and neurotoxicity were increased in case of NKCT1 than GNP-NKCT1. On isolated kidney tissue, NKCT1 released significant amount of ALP and γ-GT than GNP-NKCT1. Gold nanoconjugation with NKCT1 also reduced the lethal activity in mice. In vivo acute/sub-chronic toxicity studies in mice showed significant increase in molecular markers due to NKCT1 treatment, which was reduced by gold nanoconjugation. Histopathology study showed decreased toxic effect of NKCT1 in kidney tissue after GNP conjugation. The present study confirmed that GNP conjugation significantly decreased the toxicity profile of NKCT1. Further studies are in progress to establish the molecular mechanism of GNP induced toxicity reduction.

  3. Macrophage solubilization and cytotoxicity of indium-containing particles as in vitro correlates to pulmonary toxicity in vivo.

    Science.gov (United States)

    Gwinn, William M; Qu, Wei; Bousquet, Ronald W; Price, Herman; Shines, Cassandra J; Taylor, Genie J; Waalkes, Michael P; Morgan, Daniel L

    2015-03-01

    Macrophage-solubilized indium-containing particles (ICPs) were previously shown in vitro to be cytotoxic. In this study, we compared macrophage solubilization and cytotoxicity of indium phosphide (InP) and indium-tin oxide (ITO) with similar particle diameters (∼ 1.5 µm) and then determined if relative differences in these in vitro parameters correlated with pulmonary toxicity in vivo. RAW 264.7 macrophages were treated with InP or ITO particles and cytotoxicity was assayed at 24 h. Ionic indium was measured in 24 h culture supernatants. Macrophage cytotoxicity and particle solubilization in vitro were much greater for InP compared with ITO. To correlate changes in vivo, B6C3F1 mice were treated with InP or ITO by oropharyngeal aspiration. On Days 14 and 28, bronchoalveolar lavage (BAL) and pleural lavage (PL) fluids were collected and assayed for total leukocytes. Cell differentials, lactate dehydrogenase activity, and protein levels were also measured in BAL. All lavage parameters were greatly increased in mice treated with InP compared with ITO. These data suggest that macrophage solubilization and cytotoxicity of some ICPs in vitro are capable of predicting pulmonary toxicity in vivo. In addition, these differences in toxicity were observed despite the two particulate compounds containing similar amounts of indium suggesting that solubilization, not total indium content, better reflects the toxic potential of some ICPs. Soluble InCl3 was shown to be more cytotoxic than InP to macrophages and lung epithelial cells in vitro further suggesting that ionic indium is the primary cytotoxic component of InP. Published by Oxford University Press on behalf of the Society of Toxicology 2014. This work is written by US Government employees and is in the public domain in the US.

  4. In Vitro Evaluations and In Vivo Toxicity and Efficacy Studies of MFM501 against MRSA

    Directory of Open Access Journals (Sweden)

    Saiful Azmi Johari

    2017-01-01

    Full Text Available Previously we have discovered a synthetically derived pyrrolidone alkaloid, MFM501, exhibiting good inhibitory activity against 53 MRSA and MSSA isolates with low cytotoxicity against three normal cell-lines with IC50 values at >625 µg/ml. Time-kill assay, scanning electron microscopy (SEM analysis, in vivo oral acute toxicity test, and mice peritonitis model were carried out in this study. In the time-kill study, MFM501 showed a less than 3 log10 decrease in bacterial colony concentration value (CFU/ml which represented a bacteriostatic action while displaying a time-dependent inhibitory mechanism. Following that, SEM analysis suggested that MFM501 may exert its inhibitory activity via cytoplasmic membrane disruption. Moreover, MFM501 showed no toxicity effect on treated mice at an estimated median acute lethal dose (LD50 value of more than 300 mg/kg and less than 2000 mg/kg. For the efficacy test, a mean effective dose (ED50 of 87.16 mg/kg was obtained via a single dose oral administration. Our data demonstrated that MFM501 has the potential to be developed further as a new, safe, and effective oral-delivered antibacterial agent against MRSA isolates.

  5. In Vitro Evaluations and In Vivo Toxicity and Efficacy Studies of MFM501 against MRSA

    Science.gov (United States)

    Mohtar, Mastura; Syed Mohamad, Sharifah Aminah; Mohammat, Mohd Fazli; Sahdan, Rohana; Mohamed, Azman; Mohamad Ridhwan, Mohamad Jemain

    2017-01-01

    Previously we have discovered a synthetically derived pyrrolidone alkaloid, MFM501, exhibiting good inhibitory activity against 53 MRSA and MSSA isolates with low cytotoxicity against three normal cell-lines with IC50 values at >625 µg/ml. Time-kill assay, scanning electron microscopy (SEM) analysis, in vivo oral acute toxicity test, and mice peritonitis model were carried out in this study. In the time-kill study, MFM501 showed a less than 3 log10 decrease in bacterial colony concentration value (CFU/ml) which represented a bacteriostatic action while displaying a time-dependent inhibitory mechanism. Following that, SEM analysis suggested that MFM501 may exert its inhibitory activity via cytoplasmic membrane disruption. Moreover, MFM501 showed no toxicity effect on treated mice at an estimated median acute lethal dose (LD50) value of more than 300 mg/kg and less than 2000 mg/kg. For the efficacy test, a mean effective dose (ED50) of 87.16 mg/kg was obtained via a single dose oral administration. Our data demonstrated that MFM501 has the potential to be developed further as a new, safe, and effective oral-delivered antibacterial agent against MRSA isolates. PMID:28536702

  6. Development and Preliminary Assessment of Hemoperfusion Cartridge with Tannic Acid for Toxic Proteins' Precipitation: An In Vitro Model

    Directory of Open Access Journals (Sweden)

    Valquíria Miwa Hanai Yoshida

    2016-09-01

    Full Text Available Charcoal hemoperfusion (CHP is one of the extracorporeal removal techniques that are used to remove toxins from the body. CHP generally is considered the preferred method for extracorporeal extraction of several toxins—toxins that are adsorbed by activated charcoal. Assessments of the tannic acid's protective effects on ophidian poisoning are associated with the toxic proteins' precipitation by tannic acid. The challenge in treating a snakebite lies in removing the injected poison with minimal damage to blood constituent proteins. An alternative is CHP, and this investigation proposed to develop a column for hemoperfuser cartridge, combining charcoal granules trapped between layers of polymeric material conjugated to tannic acid, using an in vitro model scaled to the Wistar rat, which can be tested in an animal model. The cartridge was evaluated using the 22 full factorial design, in duplicate, as a method to study the effects of granulated-charcoal size and tannic acid concentration on the hematologic profile (platelet and leukocyte counts and biochemical profile (total serum protein and albumin dosages of sheep blood. The results demonstrate that charcoal in hemoperfuser cartridge: (1 decreases the serum in sheep blood volume, as consequence, (2 increases the serum proteins' concentration, and (iii exerts slight influence on albumin. The inclusion of tannic acid in hemoperfuser column precipitates some of serum proteins and albumin, decreasing their concentrations in the plasma serum. In conclusion, based on these effects we can suggest the use of 0.02 g tannic acid concentration and 8–20 mesh granulated charcoal in hemoperfuser cartridge for precipitating toxic proteins from snake venoms.

  7. Toxic trace metals and human oocytes during in vitro fertilization (IVF)

    Science.gov (United States)

    Bloom, Michael S.; Parsons, Patrick J.; Steuerwald, Amy J.; Schisterman, Enrique F.; Browne, Richard W.; Kim, Keewan; Coccaro, Gregory A.; Conti, Giulia C.; Narayan, Natasha; Fujimoto, Victor Y.

    2010-01-01

    Trace exposures to the toxic metals mercury (Hg), cadmium (Cd) and lead (Pb) may threaten human reproductive health. The aim of this study is to generate biologically-plausible hypotheses concerning associations between Hg, Cd, and Pb and in vitro fertilization (IVF) endpoints. For 15 female IVF patients, a multivariable log-binomial model suggests a 75% reduction in the probability for a retrieved oocyte to be in metaphase-II arrest for each μg/dL increase in blood Pb concentration (relative risk (RR) = 0.25, 95% confidence interval (CI) 0.03–2.50, P = 0.240). For 15 male IVF partners, each μg/L increase in urine Cd concentration is associated with an 81% decrease in the probability for oocyte fertilization (RR = 0.19, 95% CI 0.03–1.35, P = 0.097). Because of the magnitude of the effects, these results warrant a comprehensive study with sufficient statistical power to further evaluate these hypotheses. PMID:20096775

  8. Oleocanthal ameliorates amyloid-β oligomers' toxicity on astrocytes and neuronal cells: In vitro studies.

    Science.gov (United States)

    Batarseh, Yazan S; Mohamed, Loqman A; Al Rihani, Sweilem B; Mousa, Youssef M; Siddique, Abu Bakar; El Sayed, Khalid A; Kaddoumi, Amal

    2017-06-03

    Extra-virgin olive oil (EVOO) has several health promoting effects. Evidence have shown that EVOO attenuates the pathology of amyloid-β (Aβ) and improves cognitive function in experimental animal models, suggesting it's potential to protect and reduce the risk of developing Alzheimer's disease (AD). Available studies have linked this beneficial effect to oleocanthal, one of the active components in EVOO. The effect of oleocanthal against AD pathology has been linked to its ability to attenuate Aβ and tau aggregation in vitro, and enhance Aβ clearance from the brains of wild-type and AD transgenic mice in vivo. However, the ability of oleocanthal to alter the toxic effect of Aβ on brain parenchymal cells is unknown. In the current study, we investigated oleocanthal effect on modulating Aβ oligomers (Aβo) pathological events in neurons and astrocytes. Our findings demonstrated oleocanthal prevented Aβo-induced synaptic proteins, SNAP-25 and PSD-95, down-regulation in neurons, and attenuated Aβo-induced inflammation, glutamine transporter (GLT1) and glucose transporter (GLUT1) down-regulation in astrocytes. Aβo-induced inflammation was characterized by interleukin-6 (IL-6) increase and glial fibrillary acidic protein (GFAP) upregulation that were reduced by oleocanthal. In conclusion, this study provides further evidence to support the protective effect of EVOO-derived phenolic secoiridoid oleocanthal against AD pathology. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. In vitro toxicity of photodynamic antimicrobial chemotherapy on human keratinocytes proliferation.

    Science.gov (United States)

    Migliario, Mario; Rizzi, Manuela; Rocchetti, Vincenzo; Cannas, Mario; Renò, Filippo

    2013-02-01

    This in vitro experimental study has been designed to assess the effects of photodynamic antimicrobial chemotherapy (PACT) on human keratinocytes proliferation. Human keratinocytes (HaCaT) monolayers (∼0.5 cm(2)) have been irradiated with 635 nm red laser light with a fluence of 82.5 or 112.5 J/cm(2) in the absence or presence of toluidine (TB). Cell proliferation, monolayer area coverage, cytokeratin 5 (K5) and filaggrin (Fil) expression, and metalloproteinase (MMP)-2 and MMP-9 activity were measured after 72 h from laser irradiation. HaCaT proliferation was reduced by TB staining. Cell exposure to both low- and high-fluence laser irradiation in both presence and absence of TB staining reduced their proliferation and monolayer area extension. Moreover both laser treatments were able to reduce K5 and Fil expression and MMP-9 production in keratinocytes not treated with TB. These data indicate that PACT could exert toxic effects on normal proliferating keratinocytes present around parodontal pockets. The observed reduced cell proliferation along with a reduced production of enzymes involved in wound healing could alter the clinical outcome of the patients treated with PACT.

  10. Gonadotropin regulation of in vitro androgen production by reptilian testes.

    Science.gov (United States)

    Wo Tsui, H; Licht, P

    1977-04-01

    The hormonal regulation of in vitro androgen production by minced testes from 7 species of reptiles representing the 3 major orders was studied using purified follicle stimulating hormone (FSH) and luteinizing hormone (LH) from tetrapod species. Androgen content was measured by radioimmunoassay. All 7 species showed a dose-dependent response to all preparations of FSH and LH tested. However, variations were found depending on the species tested and the source of the hormone. All snake hormones were particularly inactive in turtles. Some of the variation in relative potencies of hormone reflect phylogenetic specificity in the testes. Synergism between FSH and LH was tested in the sea turtle. While subliminal doses of FSH and LH produced a small stimulation of androgen production, each alone was ineffective. Both gonadotropins have intrinsic activity with regard to the stimulation of steroidogenesis.

  11. A strategy for in vitro safety testing of nanotitania-modified textile products

    Energy Technology Data Exchange (ETDEWEB)

    Roszak, Joanna; Stępnik, Maciej; Nocuń, Marek; Ferlińska, Magdalena; Smok-Pieniążek, Anna [Nofer Institute of Occupational Medicine, 8 St Teresy St., 91-348 Łódź (Poland); Grobelny, Jarosław; Tomaszewska, Emilia [University of Lodz, Faculty of Chemistry, 163 Pomorska St, 90-236 Łódź (Poland); Wąsowicz, Wojciech [Nofer Institute of Occupational Medicine, 8 St Teresy St., 91-348 Łódź (Poland); Cieślak, Małgorzata, E-mail: cieslakm@iw.lodz.pl [Textile Research Institute, 118 Gdańska St., 90-520, Łódź (Poland)

    2013-07-15

    Highlights: • Commercially available TiO{sub 2}/Ag nanomaterials (NMs) showed higher cytotoxic effect than TiO{sub 2} NMs. • Both titania NMs in pristine form induced a weak genotoxic effect in in vitro studies. • Cytotoxic effect of textile materials modified with TiO{sub 2}/Ag NMs depended on the mode of the fiber manufacturing. • The strategy of in vitro testing of textile materials modified with NMs was proposed. -- Abstract: Titanium dioxide nanomaterials are extensively used in many applications, also for modification of textile materials. Toxicological assessment of such textile materials is currently seldom performed, mainly because of lack of appropriate guidelines. The aim of the study was to assess cytotoxic and genotoxic potential of commercially available TiO{sub 2} and TiO{sub 2}/Ag NMs in pristine form as well as polypropylene fibers modified with the NMs. Both titania NMs showed a cytotoxic effect on BALB/3T3 clone A31 and V79 fibroblasts after 72-h exposure. Both NMs induced a weak genotoxic effect in comet assay, with TiO{sub 2}/Ag being more active. In vitro micronucleus test on human lymphocytes revealed a weak mutagenic effect of both materials after 24 h of exposure. In contrast, no significant increase in micronuclei frequency was observed in the in vitro micronucleus test on V79 fibroblasts. The 24-h extracts prepared from polypropylene fibers modified with TiO{sub 2}/Ag induced a cytotoxic effect on BALB/3T3 cells which strongly depended on the mode of the fibers manufacturing. The study presents a comprehensive approach to toxicity assessment of textile fibers modified with NMs. Proposed approach may form a good “starting point” for improved future testing strategies.

  12. Validation of artificial skin equivalents as in vitro testing systems

    Science.gov (United States)

    Schmitt, Robert; Marx, Ulrich; Walles, Heike; Schober, Lena

    2011-03-01

    With the increasing complexity of the chemical composition of pharmaceuticals, cosmetics and everyday substances, the awareness of potential health issues and long term damages for humanoid organs is shifting into focus. Artificial in vitro testing systems play an important role in providing reliable test conditions and replacing precarious animal testing. Especially artificial skin equivalents ASEs are used for a broad spectrum of studies like penetration, irritation and corrosion of substances. One major challenge in tissue engineering is the qualification of each individual ASE as in vitro testing system. Due to biological fluctuations, the stratum corneum hornified layer of some ASEs may not fully develop or other defects might occur. For monitoring these effects we developed an fully automated Optical Coherence Tomography device. Here, we present different methods to characterize and evaluate the quality of the ASEs based on image and data processing of OCT B-scans. By analysing the surface structure, defects, like cuts or tears, are detectable. A further indicator for the quality of the ASE is the morphology of the tissue. This allows to determine if the skin model has reached the final growth state. We found, that OCT is a well suited technology for automatically characterizing artificial skin equivalents and validating the application as testing system.

  13. Predicting the future: opportunities and challenges for the chemical industry to apply 21st-century toxicity testing.

    Science.gov (United States)

    Settivari, Raja S; Ball, Nicholas; Murphy, Lynea; Rasoulpour, Reza; Boverhof, Darrell R; Carney, Edward W

    2015-03-01

    Interest in applying 21st-century toxicity testing tools for safety assessment of industrial chemicals is growing. Whereas conventional toxicology uses mainly animal-based, descriptive methods, a paradigm shift is emerging in which computational approaches, systems biology, high-throughput in vitro toxicity assays, and high-throughput exposure assessments are beginning to be applied to mechanism-based risk assessments in a time- and resource-efficient fashion. Here we describe recent advances in predictive safety assessment, with a focus on their strategic application to meet the changing demands of the chemical industry and its stakeholders. The opportunities to apply these new approaches is extensive and include screening of new chemicals, informing the design of safer and more sustainable chemical alternatives, filling information gaps on data-poor chemicals already in commerce, strengthening read-across methodology for categories of chemicals sharing similar modes of action, and optimizing the design of reduced-risk product formulations. Finally, we discuss how these predictive approaches dovetail with in vivo integrated testing strategies within repeated-dose regulatory toxicity studies, which are in line with 3Rs principles to refine, reduce, and replace animal testing. Strategic application of these tools is the foundation for informed and efficient safety assessment testing strategies that can be applied at all stages of the product-development process.

  14. A toxicity scoring system for the 10-day whole sediment test with Corophium insidiosum (Crawford).

    Science.gov (United States)

    Prato, Ermelinda; Biandolino, Francesca; Libralato, Giovanni

    2015-04-01

    This study developed a tool able to evaluate the potential contamination of marine sediments detecting the presence or absence of toxicity supporting environmental decision-making processes. When the sample is toxic, it is important to classify its level of toxicity to understand its subsequent effects and management practices. Corophium insidiosum is a widespread and frequently recorded species along the Mediterranean Sea, North Sea and western Baltic Sea with records also in the Atlantic Ocean and Pacific Ocean. This amphipod is found in high abundance in shallow brackish inshore areas and estuaries also with high turbidity. At Italian level, C. insidiosum is more frequently collectable than Corophium orientale, making routine toxicity tests easier to be performed. Moreover, according to the international scientific literature, C. insidiosum is more sensitive than C. orientale. Whole sediment toxicity data (10 days) with C. insidiosum were organised in a species-specific toxicity score on the basis of the minimum significance difference (MSD) approach. Thresholds to rank samples as non-toxic and toxic were based on sediment samples (n=84) from the Gulf of Taranto (Italy). A five-class toxicity score (absent, low, medium, high and very high toxicity) was developed, considering the distribution of the 90th percentile of the MSD normalised to the effects on the negative controls (samples from reference sites). This toxicity score could be useful for interpreting sediment potential impacts and providing quick responsive management information.

  15. Tests for bioequivalence of control media and test media in studies of toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, W.P.; McDonald, L.L. [Western EcoSystems Technology, Inc., Cheyenne, WY (United States)

    1995-07-01

    Statistical tests of the classical (null) hypothesis--that there is no difference in effects of control media and tested--are commonly used to make statistical inferences toward the no-observed-adverse-effect concentration. However, failing to rejects this hypothesis is not considered as scientific proof the hypothesis is true. An effect may exist, but high variation due to inadequate replication, variation in experimental units, or imprecise measurement techniques may yield data for which the hypothesis is not rejected. An experiment may also be too precise, yielding effects that are statistically significant but not biologically important. The authors propose the use of tests of bioequivalence of control media and test media to alleviate these unsatisfactory characteristics of tests and of the classical hypotheses for regulatory decisions. They review and illustrate the test for bioequivalence using acute and chronic toxicity data. They also define a procedure for determining the level of effect at which there will be high power to refute the hypothesis that there is a lack of bioequivalence if in fact the biological response in the control media is identical to the responses in the test media.

  16. In vitro antimicrobial and antiprotozoal activities, phytochemical screening and heavy metals toxicity of different parts of Ballota nigra.

    Science.gov (United States)

    Ullah, Najeeb; Ahmad, Ijaz; Ayaz, Sultan

    2014-01-01

    The study was done to assess the phytochemicals (flavonoids, terpenoids, saponins, tannin, alkaloids, and phenol) in different parts (root, stem, and leaves) of Ballota nigra and correlated it to inhibition of microbes (bacteria and fungi), protozoan (Leishmania), and heavy metals toxicity evaluation. In root and stem flavonoids, terpenes and phenols were present in ethanol, chloroform, and ethyl acetate soluble fraction; these were found to be the most active inhibiting fractions against all the tested strains of bacteria, fungi, and leishmania. While in leaves flavonoids, terpenes, and phenols were present in ethanol, chloroform, and n-butanol fractions which were the most active fractions against both types of microbes and protozoan (leishmania) in in vitro study. Ethanol and chloroform fractions show maximum inhibition against Escherichia coli (17 mm). The phytochemical and biological screenings were correlated with the presence of heavy metals in selected plant Ballota nigra. Cr was found above permissible value (above 1.5 mg/kg) in all parts of the plant. Ni was above WHO limit in B. nigra root and leaves (3.35 ± 1.20 mg/kg and 5.09 ± 0.47 mg/kg, respectively). Fe was above permissible value in all parts of B. nigra (above 20 mg/kg). Cd was above permissible value in all parts of the plant (above 0.3 mg/kg). Pb was above WHO limit (above 2 mg/kg) in all parts of Ballota nigra.

  17. Nanotechnologies for In Vitro IgE Testing.

    Science.gov (United States)

    Märki, Iwan; Rebeaud, Fabien

    2017-07-01

    This review discusses the recent advances in the development of IgE antibody assays based on nanotechnologies. IgE blood testing is an important part of the diagnostic workup of IgE-mediated hypersentivity. We also address the challenges in moving from an academic proof-of-concept to a product routinely used by allergy experts. Several nanotechnologies have been applied to the field of IgE testing: nanoparticles are used either as a support to capture analytes or as a detection tool to enhance the measurement signal. Nanofluidics allows to reduce assay time by enhancing molecular interaction. Nanotechnologies bring forth new methods for in vitro IgE testing. Substantial advantages such as lower sample volume, shorter assay time, simplified procedures, and lower analytic sensitivity, without affecting test precision and accuracy, can be achieved thanks to nanotechnologies.

  18. Body-on-a-chip systems for animal-free toxicity testing.

    Science.gov (United States)

    Mahler, Gretchen J; Esch, Mandy B; Stokol, Tracy; Hickman, James J; Shuler, Michael L

    2016-10-01

    Body-on-a-chip systems replicate the size relationships of organs, blood distribution and blood flow, in accordance with human physiology. When operated with tissues derived from human cell sources, these systems are capable of simulating human metabolism, including the conversion of a prodrug to its effective metabolite, as well as its subsequent therapeutic actions and toxic side-effects. The system also permits the measurement of human tissue electrical and mechanical reactions, which provide a measure of functional response. Since these devices can be operated with human tissue samples or with in vitro tissues derived from induced pluripotent stem cells (iPS), they can play a significant role in determining the success of new pharmaceuticals, without resorting to the use of animals. By providing a platform for testing in the context of human metabolism, as opposed to animal models, the systems have the potential to eliminate the use of animals in preclinical trials. This article will review progress made and work achieved as a direct result of the 2015 Lush Science Prize in support of animal-free testing. 2016 FRAME.

  19. Study of the genotoxicity of organic extracts from wastewater-irrigated vegetables using in vitro and in vivo biological tests.

    Science.gov (United States)

    Gao, Hongxia; Cao, Yanhua; Liu, Yingli; Liu, Nan; Guan, Weijun

    2017-03-01

    The purpose of this study was to explore genotoxicity due to organic pollutants in wastewater-irrigated vegetables using biological and chemical analyses. Chinese cabbages from wastewater-irrigated farmland were taken as the research object. For the in vitro test, DNA damage was characterized in rat hepatocytes exposed to organic extracts from the cabbages using the comet assay. For the in vivo tests, mice were exposed to organic extracts from the cabbages. DNA damage was assessed in mouse peripheral blood lymphocytes (PBLs), and chromosome damage was assessed in bone marrow cells using the comet assay and micronucleus test, respectively. For the chemical analysis, gas chromatography-mass spectrometry (GC/MS) was used to analyze the organic compounds in the organic vegetable extracts. The in vitro test results showed that the comet tail lengths of the DNA in rat hepatocytes were significantly increased in the group dosed with 0.36 g/ml (P organic content in the organic vegetable extracts from the wastewater-irrigated area (1.355 mg/kg) was significantly higher than the content in the cabbage samples from the clean-water-irrigated area (0.089 mg/kg). This finding indicated that wastewater irrigation can cause organic pollution with genetic toxicity in vegetables. This study also showed that in vivo and in vitro biological tests can reflect the joint toxicity of organic pollutants, and the test results were in accordance with the chemical analysis of the organic pollutant compositions.

  20. Gamma Radiation Reduced Toxicity of Azoxystrobin Tested on Artemia franciscana.

    Science.gov (United States)

    Dvorak, P; Zdarsky, M; Benova, K; Falis, M; Tomko, M

    2016-06-01

    Fungicide azoxystrobin toxicity was monitored by means of a 96-h biotest with Artemia franciscana nauplius stages after exposure to solutions with concentrations of 0.2, 0.4, 0.6 and 0.8 mg L(-1) irradiated with (60)Co gamma radiation with doses of 1, 2.5, 5 and 10 kGy. The effects of ionization radiation on azoxystrobin toxicity were mainly manifested by a statistically significant reduction of lethality after 72- and 96-h exposure. A maximum reduction of lethality of 72 % was achieved using doses of 1-5 kGy for an azoxystrobin initial concentration of 0.4 mg L(-1) and after 72 h of exposure. At a 96-h exposure, a difference of lethal effects reached up to 70 % for a dose of 10 kGy. The observed effect of gamma ionizing radiation on azoxystrobin toxicity suggest that this approach can be applied as an alternative for a reduction of azoxystrobin residua in food.

  1. Twelve Hours In Vitro Biocompatibility Testing of Membrane Oxygenators.

    Science.gov (United States)

    Bleilevens, Christian; Grottke, Oliver; Tillmann, Sabine; Honickel, Markus; Kopp, Rüedger; Arens, Jutta; Rossaint, Rolf

    2015-01-01

    In vitro test systems for extracorporeal membrane oxygenation (mock loop) represent an interesting alternative to complex and expensive in vivo test systems to analyze the pathomechanisms leading to insufficient biocompatibility. Data on mock loop systems are limited, and operation times are constricted to a maximum duration of 6 hr. This study aims at a 12 hr operation time and frequent monitoring of markers for insufficient biocompatibility in two experimental settings. Porcine blood circulated in a mock loop without any modifications, or the circuit was operated with a CO2-enhanced gas (5% CO2/21% O2/74% N2) in combination with a nutrient solution (phosphate-adenine-glucose-guanosine-saline-mannitol). Coagulation parameters changed over time without differences between the two groups. In the unmodified test setting, a pH increase was detected after 1 hr, followed by significantly increased levels of free hemoglobin as a marker for hemolysis and elevated numbers of activated platelets, which correlate with detected von Willebrand factor, microparticles, and interleukin-β. Proinflammatory cytokine levels were significantly increased after 12 hr. In contrast, these parameters remained constant in the modified test setting providing proof of a stable operating in vitro mock loop system with an extended/prolonged operation time.

  2. Implementing Toxicity Testing in the 21st Century (TT21C): Making safety decisions using toxicity pathways, and progress in a prototype risk assessment.

    Science.gov (United States)

    Adeleye, Yeyejide; Andersen, Melvin; Clewell, Rebecca; Davies, Michael; Dent, Matthew; Edwards, Sue; Fowler, Paul; Malcomber, Sophie; Nicol, Beate; Scott, Andrew; Scott, Sharon; Sun, Bin; Westmoreland, Carl; White, Andrew; Zhang, Qiang; Carmichael, Paul L

    2015-06-05

    Risk assessment methodologies in toxicology have remained largely unchanged for decades. The default approach uses high dose animal studies, together with human exposure estimates, and conservative assessment (uncertainty) factors or linear extrapolations to determine whether a specific chemical exposure is 'safe' or 'unsafe'. Although some incremental changes have appeared over the years, results from all new approaches are still judged against this process of extrapolating high-dose effects in animals to low-dose exposures in humans. The US National Research Council blueprint for change, entitled Toxicity Testing in the 21st Century: A Vision and Strategy called for a transformation of toxicity testing from a system based on high-dose studies in laboratory animals to one founded primarily on in vitro methods that evaluate changes in normal cellular signalling pathways using human-relevant cells or tissues. More recently, this concept of pathways-based approaches to risk assessment has been expanded by the description of 'Adverse Outcome Pathways' (AOPs). The question, however, has been how to translate this AOP/TT21C vision into the practical tools that will be useful to those expected to make safety decisions. We have sought to provide a practical example of how the TT21C vision can be implemented to facilitate a safety assessment for a commercial chemical without the use of animal testing. To this end, the key elements of the TT21C vision have been broken down to a set of actions that can be brought together to achieve such a safety assessment. Such components of a pathways-based risk assessment have been widely discussed, however to-date, no worked examples of the entire risk assessment process exist. In order to begin to test the process, we have taken the approach of examining a prototype toxicity pathway (DNA damage responses mediated by the p53 network) and constructing a strategy for the development of a pathway based risk assessment for a specific

  3. Environmental and anthropogenic factors affecting the respiratory toxicity of volcanic ash in vitro

    Science.gov (United States)

    Tomašek, Ines; Horwell, Claire J.; Damby, David E.; Ayris, Paul M.; Barošová, Hana; Geers, Christoph; Petri-Fink, Alke; Rothen-Rutishauser, Barbara; Clift, Martin J. D.

    2016-04-01

    Human exposure to inhalable volcanic ash particles following an eruption is a health concern, as respirable-sized particles can potentially contribute towards adverse respiratory health effects, such as the onset or exacerbation of respiratory and cardiovascular diseases. Although there is substantial information on the mineralogical properties of volcanic ash that may influence its biological reactivity, knowledge as to how external factors, such as air pollution, contribute to and augment the potential reactivity is limited. To determine the respiratory effects of volcanic particle interactions with anthropogenic pollution and volcanic gases we will experimentally assess: (i) physicochemical characteristics of volcanic ash relevant to respiratory toxicity; (ii) the effects of simultaneously inhaling anthropogenic pollution (i.e. diesel exhaust particles (DEP)) and volcanic ash (of different origins); (iii) alteration of volcanic ash toxicity following interaction with volcanic gases. In order to gain a first understanding of the biological impact of the respirable fraction of volcanic ash when inhaled with DEP in vitro, we used a sophisticated 3D triple cell co-culture model of the human alveolar epithelial tissue barrier. The multi-cellular system was exposed to DEP [0.02 mg/mL] and then exposed to either a single or repeated dose of well-characterised respirable volcanic ash (0.26 ± 0.09 or 0.89 ± 0.29 μg/cm2, respectively) from the Soufrière Hills volcano, Montserrat for a period of 24 hours using a pseudo-air liquid interface approach. Cultures were subsequently assessed for adverse biological endpoints including cytotoxicity, oxidative stress and (pro)-inflammatory responses. Results indicated that the combination of DEP and respirable volcanic ash at sub-lethal concentrations incited a significant release of pro-inflammatory markers that was greater than the response for either DEP or volcanic ash, independently. Further work is planned, to determine if

  4. Sex Differences in Liver Toxicity—Do Female and Male Human Primary Hepatocytes React Differently to Toxicants In Vitro?

    OpenAIRE

    Milena Mennecozzi; Brigitte Landesmann; Taina Palosaari; Georgina Harris; Maurice Whelan

    2014-01-01

    There is increasing amount of evidence for sex variation in drug efficiency and toxicity profiles. Women are more susceptible than men to acute liver injury from xenobiotics. In general, this is attributed to sex differences at a physiological level as well as differences in pharmacokinetics and pharmacodynamics, but neither of these can give a sufficient explanation for the diverse responses to xenobiotics. Existing data are mainly based on animal models and limited data exist on in vitro se...

  5. Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics

    DEFF Research Database (Denmark)

    Rathe, Mathias; Lise, Kristensen,; Ellermann-Eriksen, Svend

    Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics......Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics...

  6. Evaluation of Daphnia ambigua for Routine Aquatic Toxicity Testing at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L. [Westinghouse Savannah River Company, Aiken, SC (United States); Harmon, S.M. [University of South Carolina, Columbia, SC (United States)

    1997-09-01

    Short-term whole effluent toxicity testing, which is currently a requirement of the U.S. EPA`s National Pollution Discharge Elimination System (NPDES), commonly uses the cladoceran species Ceriodaphnia dubia. Despite the advantages to using a common test species to model the toxic effects of effluents, it could be argued that toxicity test results would be more meaningful if a wider variety of test organisms were commonly used. One particular argument against C. dubia is that tests conducted with this species do not always reflect local, site-specific conditions. The careful selection and use of an indigenous test species would produce a more realistic model of local instream effects and would account for regional differences in water quality. Permitted effluent discharges from Savannah River Site (SRS), a government weapons facility operated by the U.S. Department of Energy, require toxicity testing with C. dubia. However, water quality in these receiving streams is markedly different (lower pH and hardness) from standard laboratory water used for the culturing and testing of C. dubia, and it has been shown that this receiving water presents varying degrees of toxicity to C. dubia. Based on these results, it is possible that toxic effects observed during an effluent study could be the result of test organism stress from the dilution water and not the effects of SRS effluents. Therefore, this study addressed the substitution of C. dubia with an indigenous cladoceran species, Daphnia ambigua for routine regulatory testing at SRS. Given the indigenous nature of this species, combined with the fact that it has been successfully cultured by other investigators, D. ambigua was ideal for consideration as a replacement for C. dubia, but further study of the overall success and sensitivity of laboratory-reared D. ambigua was required. This investigation determined that D. ambigua could be laboratory cultured with only minimal changes to established regulatory protocol and

  7. Toxicological assessment of kretek cigarettes: Part 2: kretek and American-blended cigarettes, smoke chemistry and in vitro toxicity.

    Science.gov (United States)

    Piadé, J-J; Roemer, E; Dempsey, R; Hornig, G; Deger Evans, A; Völkel, H; Schramke, H; Trelles-Sticken, E; Wittke, S; Weber, S; Schorp, M K

    2014-12-01

    Two commercial kretek cigarettes typical for the Indonesian market and a reference kretek cigarette were compared to the American-blended reference cigarette 2R4F by smoke chemistry characterization and in vitro cytotoxicity and mutagenicity assessments. Despite the widely diverse designs and deliveries of the selected kretek cigarettes, their smoke composition and in vitro toxicity data present a consistent pattern when data were normalized to total particulate matter (TPM) deliveries. This confirms the applicability of the studies' conclusions to a wide range of kretek cigarette products. After normalization to TPM delivery, nicotine smoke yields of kretek cigarettes were 29-46% lower than that of the 2R4F. The yields of other nitrogenous compounds were also much lower, less than would be expected from the mere substitution of one third of the tobacco filler by clove material. Yields of light molecular weight pyrolytic compounds, notably aldehydes and hydrocarbons, were reduced, while yields of polycyclic aromatic hydrocarbons were unchanged and phenol yield was increased. The normalized in vitro toxicity was lowered accordingly, reflecting the yield reductions in gas-phase cytotoxic compounds and some particulate-phase mutagenic compounds. These results do not support a higher toxicity of the smoke of kretek cigarettes compared to American-blended cigarettes. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Developmental toxicity testing in the 21st century: the sword of Damocles shattered by embryonic stem cell assays?

    Science.gov (United States)

    Seiler, Andrea; Oelgeschläger, Michael; Liebsch, Manfred; Pirow, Ralph; Riebeling, Christian; Tralau, Tewes; Luch, Andreas

    2011-11-01

    Modern society faces an inherent dilemma. In our globalized society, we are spoilt for choice by an ever-increasing number of products, many of which are made of new materials and compound mixtures. At the same time, as consumers we got accustomed to the idea of a life minimized for risk, including our own exposure to chemicals from the environment or to compounds present in and released from everyday products. Chemical safety testing bridges these obviously diverging interests, and the corresponding legislation has hence been tremendously extended (e.g., introduction of the European legislation REACH in 2007). However, the underlying regulatory toxicology still relies mainly on animal testing, which is relatively slow, expensive, and ethically arguable. Meanwhile, recent years have seen a surge in efforts to develop alternative testing systems and strategies. Expectations are particularly high for the applicability of stem cells as test systems especially for developmental toxicity testing in vitro. For the first time in history, test systems can be based on differentiating cells and tissue progenitors in culture, thus bringing the 'vision of toxicity testing in the 21st century' a step closer.

  9. [An in vitro study on toxic effect of vanadium-titanium-magnetite dust on alveolar macrophage in rabbits].

    Science.gov (United States)

    Song, Y; Chen, Q; Guan, Y

    1998-11-01

    To study the toxic effect of vanadium-titanium-magnetite (VTM) dust on alveolar macrophage (AM) and its hazardous extent. Survival rates, morphology and function of AM were compared in rabbits exposed to dust of VTM, vanadium oxide, titanium dioxide and silica in various doses and length of time with in vitro cell culture and putamen membrane cover glass transmission electron microscopy, and changes in activities of lactic dehydrogenase (LDH) and acid phosphatase (ACP) in cell culture were measured. Exposure to all the four kinds of dust could lead to decrease in survival rate of AM, increase in activities of LDH and ACP in the cell culture, and changes in their morphology and function to the extent dependent on the nature of dust. Toxic effect of exposure to VTM dust was lower than that to vanadium oxide and silica, but higher than that to titanium dioxide, which had slight toxic effect.

  10. Acute toxicity and cytotoxicity evaluation of Dendrobium moniliforme aqueous extract in vivo and in vitro

    Science.gov (United States)

    Lee, Mu-Jin; Jung, Ho-Kyung; Kim, Min-Suk; Jang, Ji-Hun; Sim, Mi-Ok; Kim, Tea-Mook; Park, Ho; Ahn, Byung-Kwan; Cho, Hyun-Woo; Cho, Jung-Hee

    2016-01-01

    Dendrobium moniliforme (L.) Sw., an herb of the Orchidaceae family, has long been used in traditional medicine to strengthen bones, nourish the stomach, and promote the production of bodily fluid. Recently, polysaccharides isolated from Dendrobium have been used in functional foods and nutraceutical products. A traditional method to process Dendrobium is to soak fresh stems in an ethanol solution, which is the most important factor to ensure high yields of aqueous-extractable polysaccharides. The present study was carried out to investigate the potential acute toxicity of D. moniliforme aqueous extract (DMAE), by a single oral dose in Sprague-Dawley rats. The test article was orally administered once by gavage to male and female rats at doses of 0, 2,500, and 5,000 mg/kg body weight (n=5 male and female rats for each dose). Throughout the study period, no treatment-related deaths were observed and no adverse effects were noted in clinical signs, body weight, food consumption, serum biochemistry, organ weight, or gross findings at any dose tested. The results show that a single oral administration of DMAE did not induce any toxic effects at a dose below 5,000 mg/kg in rats, and the minimal lethal dose was considered to be over 5,000 mg/kg body weight for both sexes. With respect to cytotoxicity, the cell viability of human embryonic kidney (HEK293) cells was less than 50% when the cells were treated with 10 mg/mL aqueous extract for 24 h. PMID:27729930

  11. Development of protocols for chronic toxicity testing of Pacific marine species

    Energy Technology Data Exchange (ETDEWEB)

    Langdon, C.J.; Seim, W.K.; Hoffman, R.L.; Weber, L.

    1990-03-01

    The development of a year-round capability for conducting short-term toxicity tests for estimating chronic-effect levels of toxic materials with a native Pacific coast fish and a native Pacific coast mysid shrimp was the goal of the project. In order to achieve acceptable sensitivity as a surrogate for chronic toxicity tests, targeting the reproductive portion of the mysid life cycle and all or part of the embryonic, larval, or early post-larval portion of the fish life cycle was deemed necessary. This targeting is consistent with conclusions based upon earlier work in developing similar tests with Atlantic coast, Gulf coast, and freshwater fish and invertebrates.

  12. The potentiation effect makes the difference: Non-toxic concentrations of ZnO nanoparticles enhance Cu nanoparticle toxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lingxiangyu [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Fernández-Cruz, María Luisa; Connolly, Mona [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain); Conde, Estefanía; Fernández, Marta [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid 28040 (Spain); Schuster, Michael [Department of Chemistry, Technische Universität München, Garching 85747 (Germany); Navas, José María, E-mail: jmnavas@inia.es [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain)

    2015-02-01

    Here we examined whether the addition of a non-toxic concentration (6.25 μg/mL) of zinc oxide nanoparticles (ZnONPs: 19, 35 and 57 nm, respectively) modulates the cytotoxicity of copper nanoparticles (CuNPs, 63 nm in size) in the human hepatoma cell line HepG2. The cytotoxic effect of CuNPs on HepG2 cells was markedly enhanced by the ZnONPs, the largest ZnONPs causing the highest increase in toxicity. However, CuNPs cytotoxicity was not affected by co-incubation with medium containing only zinc ions, indicating the increase in toxicity might be attributed to the particle form of ZnONPs. Transmission electron microscopy (TEM) revealed the presence of CuNPs and ZnONPs inside the cells co-exposed to both types of NP and outflow of cytoplasm through the damaged cell membrane. Inductively coupled plasma mass spectrometry (ICP-MS) determined an increase in the concentration of zinc and a decrease in that of copper in co-exposed cells. On the basis of these results, we propose that accumulation of large numbers of ZnONPs in the cells alters cellular membranes and the cytotoxicity of CuNPs is increased. - Highlights: • ZnONPs at non-toxic concentrations increased the toxicity of CuNPs in vitro. • ZnONPs of larger size provoked a stronger synergistic effect with CuNPs. • The synergistic effect was attributed to the particle fraction of ZnONPs.

  13. The ToxBank Data Warehouse: Supporting the Replacement of In Vivo Repeated Dose Systemic Toxicity Testing.

    Science.gov (United States)

    Kohonen, Pekka; Benfenati, Emilio; Bower, David; Ceder, Rebecca; Crump, Michael; Cross, Kevin; Grafström, Roland C; Healy, Lyn; Helma, Christoph; Jeliazkova, Nina; Jeliazkov, Vedrin; Maggioni, Silvia; Miller, Scott; Myatt, Glenn; Rautenberg, Michael; Stacey, Glyn; Willighagen, Egon; Wiseman, Jeff; Hardy, Barry

    2013-01-01

    The aim of the SEURAT-1 (Safety Evaluation Ultimately Replacing Animal Testing-1) research cluster, comprised of seven EU FP7 Health projects co-financed by Cosmetics Europe, is to generate a proof-of-concept to show how the latest technologies, systems toxicology and toxicogenomics can be combined to deliver a test replacement for repeated dose systemic toxicity testing on animals. The SEURAT-1 strategy is to adopt a mode-of-action framework to describe repeated dose toxicity, combining in vitro and in silico methods to derive predictions of in vivo toxicity responses. ToxBank is the cross-cluster infrastructure project whose activities include the development of a data warehouse to provide a web-accessible shared repository of research data and protocols, a physical compounds repository, reference or "gold compounds" for use across the cluster (available via wiki.toxbank.net), and a reference resource for biomaterials. Core technologies used in the data warehouse include the ISA-Tab universal data exchange format, REpresentational State Transfer (REST) web services, the W3C Resource Description Framework (RDF) and the OpenTox standards. We describe the design of the data warehouse based on cluster requirements, the implementation based on open standards, and finally the underlying concepts and initial results of a data analysis utilizing public data related to the gold compounds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. In vitro immunopotentiating properties and tumour cell toxicity induced by Lophophora williamsii (peyote) cactus methanolic extract.

    Science.gov (United States)

    Franco-Molina, M; Gomez-Flores, R; Tamez-Guerra, P; Tamez-Guerra, R; Castillo-Leon, L; Rodríguez-Padilla, C

    2003-11-01

    Lophophora williamsii, also known as peyote, is found primarily in dry regions from Central Mexico, including the Mexican States of Nayarit, San Luis Potosí, Zacatecas, Nuevo León, Chihuahua, Coahuila and Tamaulipas, to Texas particularly in regions along Rio Grande. Peyote extracts have been associated with stimulating the central nervous system and regulating blood pressure, sleep, hunger and thirst. However, there is no evidence of any effect of peyote on the immune system or against tumour cell growth. The present study was designed to evaluate the in vitro effects of peyote methanolic extracts on some parameters of mouse and human leukocyte immunocompetence and tumour cell growth. Peyote extract (0.18-18 micro g/mL) activated nitric oxide production by murine macrophages, and stimulated up to 2.4-fold proliferation of murine thymic lymphocytes. In addition, peyote extract induced up to 1.85-, 2.29- and 1.89-fold increases in mRNA signal of IL-1, IL-6 and IL-8 by human leukocytes. Also examined were the effects of peyote extracts on murine lymphoma L5178Y-R and fi broblastoma L929, and human myeloid U937 and mammary gland MCF7 tumour cell growth using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). Peyote extracts were toxic for MCF7, L5178Y-R, U937 and L929 (18 mg/mL peyote extract caused 1.3%, 8%, 45% and 60% viability respectively) cell lines. Copyright 2003 John Wiley & Sons, Ltd.

  15. Toxicity Tests of Whole Sediment Samples Using the Hyallella (H. azteca) Survival and Growth Tests (ASTM E 1283-93)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — 10-day toxicity tests using Hyalella azteca were conducted with sediment samples collected by the U.S. Fish & Wildlife Service, Bloomington, Indiana facility to...

  16. An in vitro approach to assess the toxicity of inhaled tobacco smoke components: nicotine, cadmium, formaldehyde and urethane.

    Science.gov (United States)

    Balharry, Dominique; Sexton, Keith; BéruBé, Kelly A

    2008-02-03

    One of the first lines of defence to inhaled toxins is the barrier formed by the tracheobronchial epithelium, making this the ideal region for studying the toxicity of inhaled substances. This study utilises a highly differentiated, three-dimensional, in vitro model of human upper respiratory tract epithelium (EpiAirway-100) to measure the acute toxicological responses to well-characterised tobacco smoke components. To determine the suitability of this model for screening inhaled toxicants, the EpiAirway tissue model (ETM) was treated apically with tobacco smoke components (nicotine, formaldehyde, cadmium, urethane) which are known to induce a variety of toxic effects (e.g. cytotoxic, thrombogenic, carcinogenic). A range of concentrations were used to model different mechanisms and severity of toxicity which were then compared to known in vivo responses. Similar trends in stress response occurred, with distinct alterations to the tissue in response to all four toxins. At high concentrations, cell viability decreased and tight junctions were degraded, but at sub-toxic concentrations epithelial resistance (indicating tissue integrity) increased 20-60% from control. This peak in resistance coincided with an increase in secreted protein levels, elevated cytokine release and goblet cell hyperplasia and hypertrophy. In conclusion, acute exposure to tobacco smoke components induces measurable toxic responses within human respiratory epithelium. Sub-toxic concentrations appear to illicit a protective response by increasing mucus secretion and mediating immune responses via cytokine release. These responses are comparable to human in vivo responses, indicating potential for the ETM as a tool for screening the toxicity of inhaled compounds.

  17. A glycine zipper motif mediates the formation of toxic β-amyloid oligomers in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Fan Emily Y

    2011-08-01

    Full Text Available Abstract Background The β-amyloid peptide (Aβ contains a Gly-XXX-Gly-XXX-Gly motif in its C-terminal region that has been proposed to form a "glycine zipper" that drives the formation of toxic Aβ oligomers. We have tested this hypothesis by examining the toxicity of Aβ variants containing substitutions in this motif using a neuronal cell line, primary neurons, and a transgenic C. elegans model. Results We found that a Gly37Leu substitution dramatically reduced Aβ toxicity in all models tested, as measured by cell dysfunction, cell death, synaptic alteration, or tau phosphorylation. We also demonstrated in multiple models that Aβ Gly37Leu is actually anti-toxic, thereby supporting the hypothesis that interference with glycine zipper formation blocks assembly of toxic Aβ oligomers. To test this model rigorously, we engineered second site substitutions in Aβ predicted by the glycine zipper model to compensate for the Gly37Leu substitution and expressed these in C. elegans. We show that these second site substitutions restore in vivo Aβtoxicity, further supporting the glycine zipper model. Conclusions Our structure/function studies support the view that the glycine zipper motif present in the C-terminal portion of Aβ plays an important role in the formation of toxic Aβ oligomers. Compounds designed to interfere specifically with formation of the glycine zipper could have therapeutic potential.

  18. 40 CFR 795.120 - Gammarid acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... definitions also apply to this guideline: Death means the lack of reaction of a test organism to gentle... concentration, i.e., that concentration of a chemical in air or water killing 50 percent of the test batch of... dilution water through each chamber is adjusted to the rate desired. In a static test, the test substance...

  19. TPK Sarimukti, Cipatat, West Bandung compost toxicity test using Allium test

    Energy Technology Data Exchange (ETDEWEB)

    Wardini, Trimurti Hesti; Notodarmojo, Peni Astrini [Biology Study Program, School of Life Science and Technology, Bandung Institute of Technology (Indonesia)

    2015-09-30

    TPK Sarimukti, Cipatat, West Bandung produced 2 kinds of compost from traditional market waste, liquid and solid compost. The aim of this research is to evaluate toxicity of compost produced in TPK Sarimukti using shallots (Allium cepa). Tests carried out by treated shallots with liquid compost (2,5%, 5%, 10% and 12,5% (w/v)) or solid compost (25%, 50%, 75% and 100% (w/v)) for 48 hours. Results showed reduced root growth rate and mitotic index (MI) in accordance with increased concentrations of compost. Sub lethal concentrations are liquid compost 5% and 10% and solid compost 75%. Lethal concentrations are liquid compost 12,5 % and solid compost 100%. Micronuclei (MN) increased with increase in liquid compost concentration. MN found at very high frequencies in highest solid compost concentration (100%), but very low at lower concentrations. Cells with binuclei and cell necrosis increased with increasing concentrations of given compost. Nuclear anomalies (NA) found in high frequency in 75% and 100% solid compost. Based on research, we can conclude that liquid compost is more toxic because it can reduce MI and root growth rate at lower concentrations than solid compost. Both types of compost have genotoxic properties because it can induce chromosome aberration (CA), MN, binuclei and NA formation.

  20. The assessment of sewage sludge gasification by-products toxicity by ecotoxicologial test.

    Science.gov (United States)

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

    The process of gasification of sewage sludge generates by-products, which may be contaminated with toxic and hazardous substances, both organic and inorganic. It is therefore important to assess the environmental risk associated with this type of waste. The feasibility of using an ecotoxicological tests for this purpose was determined in the presented study. The applied tests contained indicator organisms belonging to various biological groups (bacteria, crustaceans, plants). The subject of the study were solid (ash, char) and liquid (tar) by-products generated during gasification (in a fixed bed reactor) of dried sewage sludge from various wastewater treatment systems. The tested samples were classified based on their toxic effect. The sensitivity of the indicator organisms to the tested material was determined. In-house procedures for the preparation for toxicity analysis of both sewage sludge and by-products generated during the gasification were presented. The scope of work also included the determination of the effect of selected process parameters (temperature, amount of gasifying agent) on the toxicity of gasification by-products depending on the sewage sludge source. It was shown that both the type of sewage sludge and the parameters of the gasification process affects the toxicity of the by-products of gasification. However, the results of toxicity studies also depend on the type of ecotoxicological test used, which is associated with a different sensitivity of the indicator organisms. Nevertheless, it may be concluded that the by-products formed during the gasification of the low toxicity sewage sludge can be regarded as non-toxic or low toxic. However, the results analysis of the gasification of the toxic sludge were not conclusive, which leads to further research needs in this area. © The Author(s) 2015.

  1. IN VITRO ANTAGONISTIC ACTIVITIES OF INDONESIAN MARINE SPONGE AAPTOS AAPTOS AND CALLYSPONGIA PSEUDORETICULATA EXTRACTS AND THEIR TOXICITY AGAINST Vibrio spp.

    Directory of Open Access Journals (Sweden)

    Rosmiati Rosmiati

    2011-12-01

    Full Text Available Vibriosis is one of diseases which often results in mass mortality of Penaeus monodon larval rearing systems. It attacks shrimp of all stages in zoea, mysis and shrimp postlarva stage. This disease is caused by Vibrio spp, particularly Vibrio harveyi (a luminescent bacterium. Several kinds of antibiotics and chemical material have been used to overcome the disease but they have side effects to environment and human. The searching of bioactive compounds as an alternative treatment has been done for multi purposes. In this study diethyl eter, butanol and aqueous extract of Indonesian sponges Aaptos aaptos and Callyspongia pseudoreticulata were tested for in vitro activity against Vibrio spp. and Vibrio harveyi by using disc diffusion method. The result showed that all extracts of Aaptos aaptos gave a positive antibacterial activity towards those pathogenic bacteria. Meanwhile, only butanol extract of Callyspongia pseudoreticulata obtained to exhibit an antibacterial activity on those pathogenic bacteria. The strong anti-vibrio activity were shown by butanol and aqueous extract of Aaptos aaptos with the minimum inhibitory concentration (MIC value of 0.313 and 0.625 mg/mL, respectively. Whilst, the butanol extract of Callyspongia pseudoreticulata indicated a low antibacterial activity with the MIC value of 10 mg/mL. Toxicity of those active extracts was evaluated by Brine Shrimp Lethality Test (BST. Interestingly, butanol and aqueous extracts of Aaptos aaptos did not show any toxic effect in Artemia salina larvae up to 8 x MIC (2.504 mg/mL and 5.000 mg/mL. It is the first report for the anti-vibr io activity of both Aaptos aaptos and Callyspongia pseudoreticulata. This results suggest that Aaptos aaptos has a potential to be used as a source of alternative compound to vibriosis prevention for mariculture.

  2. Interlaboratory Evaluation of Hyalella Azteca and Chironomus Tentans Short-term and Long-term Sediment Toxicity Tests

    Science.gov (United States)

    This paper presents the results of interlaboratory toxicity tests on sediment toxicity methods for use in routine testing and this data has been presented in an EPA report and this is a summary of that data.

  3. Sensitivity comparison of laboratory-cultured and field-collected amphipod Corophium multisetosum in toxicity tests.

    Science.gov (United States)

    Menchaca, Iratxe; Belzunce, María Jesús; Franco, Javier; Garmendia, Joxe Mikel; Montero, Natalia; Revilla, Marta

    2010-04-01

    The feasibility of using lab-cultured amphipods Corophium multisetosum (Stock 1952) to evaluate the toxicity of contaminants present within marine sediments was studied. This was done by comparing the sensitivity of lab-cultured amphipods in a cadmium toxicity test and to toxic sediment samples, during a 10-days bioassay, with field collected individuals. Different responses were observed between field and cultured individuals. Cadmium test indicated high temporal variability in the LC(50) values of field amphipods (2.40-6.55 mg L(-1)). Sensitivity of cultured amphipods was within the seasonal range of the field individuals (5.81 mg L(-1), LC(50)). However, culture amphipods showed much lower sensitivity in toxic sediment samples. Our results indicate that sensitivity should be determined using a sediment matrix, if the assessment of toxicity is based upon bioassays performed with cultured burrower-amphipods.

  4. Tapioca-starch wastewater toxicity characterized by Microtox and duckweed tests

    Energy Technology Data Exchange (ETDEWEB)

    Bengtsson, Bengt-Erik (Stockholm University, Institute of Applied Environmental Research, Laboratory for Aquatic Ecotoxicology, Nykoeping (Sweden)); Triet, T. (University of Wisconsin, Institute for Environmental Studies, Madison, WI (United States))

    1994-12-01

    The toxicity of treated and untreated effluents from a tapioca (cassava), Manihot esculenta, starch industry in Thailand were tested on Microtox and a subtropical duckweed, Lemna aequinoctialis. Untreated samples demonstrated high toxicity in both tests, but also the treated effluent was toxic to duckweed. Aging of wastewater resulted in decreased toxicity which was partly correlated to cyanide content, but other (unidentified) components of the tapioca tubers also contribute to the toxicity. Considering the present findings and the fact that the majority of the tapioca starch industries in Southeast Asia have no effluent treatment there is a great risk for severe effects on crops (e.g. young stages of rice, vegetables, etc.) when the wastewater in traditional way is used for irrigation of farmland. Negative effects on local aquaculture and/or sensitive stages of valuable feral fish and crustacea populations in receiving water bodies can also be expected. 32 refs, 6 tabs

  5. Development and application of a marine sediment pore-water toxicity test using Ulva fasciata zoospores

    Energy Technology Data Exchange (ETDEWEB)

    Hooten, R.L.; Carr, R.S. [Texas A and M Univ., Corpus Christi, TX (United States). Geological Survey

    1998-01-01

    An acute (96 h) pore-water toxicity test protocol using germination and growth of Ulva fasciata zoospores as endpoints was developed to test the toxicity of marine and estuarine sediment pore-water samples. Tests with an organic toxicant (sodium dodecyl sulfate; SDS), three metals (Cd, Cu, and Zn), and ammonia (NH{sub 3}) were conducted to determine zoospore sensitivity. Zoospore germination and gametophyte growth were as sensitive to SDS as sea urchin (Arbacia punctulata) fertilization and embryological development. Zoospore sensitivity to metals was greater than or comparable to that of adult macroalgae. Zoospores were less sensitive to NH{sub 3} than were other commonly used toxicity test organisms. Test results using this algal assay with sediment pore-water samples with high NH{sub 3} concentrations were compared with results from sea urchin fertilization and embryological development tests for the same samples. Ulva fasciata zoospore germination was not affected by samples with high NH{sub 3} concentrations that were toxic in both sea urchin tests. Zoospore tolerance of NH{sub 3} and sensitivity to other contaminants indicate that their response may be useful in toxicity identification evaluation studies with pore-water samples that contain high concentrations of unionized NH{sub 3}.

  6. Development and application of a marine sediment pore-water toxicity test using Ulva fasciata zoospores

    Science.gov (United States)

    Hooten, Russell L.; Carr, R. Scott

    1998-01-01

    An acute (96 h) pore-water toxicity test protocol using germination and growth of Ulva fasciatazoospores as endpoints was developed to test the toxicity of marine and estuarine sediment pore-water samples. Tests with an organic toxicant (sodium dodecyl sulfate; SDS), three metals (Cd, Cu, and Zn), and ammonia (NH3) were conducted to determine zoospore sensitivity. Zoospore germination and gametophyte growth were as sensitive to SDS as sea urchin (Arbacia punctulata) fertilization and embryological development. Zoospore sensitivity to metals was greater than or comparable to that of adult macroalgae. Zoospores were less sensitive to NH3than were other commonly used toxicity test organisms. Test results using this algal assay with sediment pore-water samples with high NH3 concentrations were compared with results from sea urchin fertilization and embryological development tests for the same samples. Ulva fasciatazoospore germination was not affected by samples with high NH3 concentrations that were toxic in both sea urchin tests. Zoospore tolerance of NH3 and sensitivity to other contaminants indicate that their response may be useful in toxicity identification evaluation studies with pore-water samples that contain high concentrations of unionized NH3.

  7. Modifying Foods and Feeding Regimes to Optimize the Performance of Hyalella azteca during Chronic Toxicity Tests

    Science.gov (United States)

    The amphipod Hyalella azteca is commonly used to assess the toxicity of sediments and waters. However, laboratories have reported varying success in maintaining healthy cultures and in obtaining consistent growth and reproduction (where applicable), especially during tests...

  8. Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0) tracks the submissions of health and safety data submitted to the EPA either as required or...

  9. Suboptimal performance on neuropsychological tests in patients with suspected chronic toxic encephalopathy

    NARCIS (Netherlands)

    van Hout, MSE; Schmand, B; Wekking, EM; Hageman, G; Deelman, BG

    Suboptimal performance during neuropsychological testing can seriously complicate assessment in behavioral neurotoxicology. We present data on the prevalence of suboptimal performance in a group of Dutch patients with suspected chronic toxic encephalopathy (CTE) after long-term occupational exposure

  10. Suboptimal performance on neuropsychological tests in patients with suspected chronic toxic encephalopathy

    NARCIS (Netherlands)

    van Hout, Moniek S. E.; Schmand, Ben; Wekking, Ellie M.; Hageman, Gerard; Deelman, Betto G.

    2003-01-01

    Suboptimal performance during neuropsychological testing can seriously complicate assessment in behavioral neurotoxicology. We present data on the prevalence of suboptimal performance in a group of Dutch patients with suspected chronic toxic encephalopathy (CTE) after long-term occupational exposure

  11. In Vitro and In Vivo Toxicity of Several Fungicides and Timorex Gold Biofungicide to Pythuim aphanidermatum

    Directory of Open Access Journals (Sweden)

    Milica Mihajlović

    2013-01-01

    Full Text Available A survey of in vitro and in vivo sensitivity of Pythuim aphanidermatum to several commercialfungicides and a biofungicide was undertaken. An isolate of P. aphanidermatum pathogenicto pepper was collected from a naturally infested greenhouse soil from SmederevskaPalanka, Serbia. The P. aphanidermatum isolate was sensitive to all tested products. Theobtained EC50 values were as follows: 10.21 mg/l for propamocarb-hydrochloride, 302.65mg/l for fosetyl-Al, 11.18 mg/l for mancozeb, 1.27 mg/l for mefenoxam, 0.05 mg/l for azoxystrobin,and 175.33 mg/l for tea tree oil. Under greenhouse conditions, fosetyl-Al was themost efficient fungicide among the tested substances (97.5%. The biofungicide tea tree oil(Timorex Gold (35.0% exhibited the lowest efficacy among the tested materials, but it wasstill significantly better than the untreated control plot. The efficacies of propamocarb-hydrochloride(Previcur 607 SL, mancozeb (Mankogal 80 WP, azoxystrobin (Quadris and mefenoxam(Ridomil gold 480 SL, were 72.5%, 77.5%, 57.5% and 75.0%, respectively.

  12. 40 CFR 797.1300 - Daphnid acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... the carapace. (iv) Feeding. A variety of foods (e.g., unicellular green algae) have been demonstrated... introduction or the test substance delivery system and the flow rate (in flow-through test) expressed as volume...

  13. Revolutionizing Toxicity Testing For Predicting Developmental Outcomes (DNT4)

    Science.gov (United States)

    Characterizing risk from environmental chemical exposure currently requires extensive animal testing; however, alternative approaches are being researched to increase throughput of chemicals screened, decrease reliance on animal testing, and improve accuracy in predicting adverse...

  14. Solubility-driven toxicity of CuO nanoparticles to Caco2 cells and Escherichia coli: Effect of sonication energy and test environment.

    Science.gov (United States)

    Käkinen, Aleksandr; Kahru, Anne; Nurmsoo, Helen; Kubo, Anna-Liisa; Bondarenko, Olesja M

    2016-10-01

    Due to small size and high surface energy nanoparticles (NPs) tend to agglomerate and precipitate. To avoid/diminish that, sonication of NPs stock suspensions prior toxicity testing is often applied. Currently, there is no standardized particle sonication protocol available leading to inconsistent toxicity data, especially if toxicity is driven by NPs' dissolution that may be enhanced by sonication. In this study we addressed the effect of sonication on hydrodynamic size (Dh), dissolution and toxicity of copper oxide (CuO) NPs to mammalian cell line Caco-2 in vitro and bacteria Escherichia coli in the respective test environments (cell culture MEM medium, bacterial LB medium and deionised (DI) water). NPs were suspended using no sonication, water bath and probe sonication with different energy intensities. Increased sonication energy (i) decreased the Dh of CuO NPs in all three test environments; (ii) increased dissolution of NPs in MEM medium and their toxicity to Caco-2; (iii) increased dissolution of NPs in LB medium and their bioavailability to E. coli; and (iv) had no effect on dissolution and antibacterial effects of NPs in DI water. Thus, to reduce variations in dissolution and toxicity, we recommend sonication of NPs in DI water following the dilution into suitable test media. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. An Evaluation of Select Test Variables Potentially Affecting Acute Oil Toxicity.

    Science.gov (United States)

    Echols, Brandi S; Smith, A; Gardinali, P; Rand, G

    2016-02-01

    In the wake of the Deepwater Horizon incident (2010) in the Gulf of Mexico, an abundance of research studies have been performed, but the methodologies used have varied making comparisons and replication difficult. In this study, acute toxicity tests with mysids and inland silversides were performed to examine the effect of different variables on test results. The toxicity test variables evaluated in this study included (1) open versus closed static test chambers, (2) natural versus artificial diluent, (3) aerated versus nonaerated test solution, and (4) low versus medium energy water-accommodated (WAF) mixing energies. The use of tests using natural or artificial diluent showed no difference in either toxicity test or analytical chemistry results. Based on median lethal concentrations (LC50) of WAFs of unweathered oil (MASS), mysid tests performed in closed chambers were approximately 41 % lower than LC50 values from open-chamber studies, possibly a result of the presence of low-molecular weight volatile aromatics (i.e., naphthalenes). This research also showed that using a medium-energy WAF (with a 20–25 % vortex) increases the number of chemical components compared with low-energy WAF, thus affecting the composition of the exposure media and increasing toxicity. The comparison of toxic units as a measure of the potential toxicity of fresh and weathered oils showed that weathered oils (e.g., Juniper, CTC) are less toxic than the unweathered MASS oil. In the event of future oil spills, these variables should be considered to ensure that data regarding the potential toxicity and environmental risk are of good quality and reproducible.

  16. Biocompatibility of dielectric Ta2O5 coatings in in vitro tests

    Science.gov (United States)

    Donkov, N.; Mateev, E.; Zykova, A.; Safonov, V.; Luk'yanchenko, V.

    2010-04-01

    A study was performed on the impact of the structure and properties of e-beam evaporated Ta2O5 films on the cell/material response. The surface properties and structure the films were investigated by means of XPS and XRD. The cyto toxicity and cyto compatibility were estimated by in vitro tests. Other parameters, such as the surface free energy (SFE) and fractional polarity, were determined by means of the Wu, and Owens-Wendt-Rabel-Kaelble methods. The dependence was followed of the cells adhesive behavior on the coatings surface composition and parameters. The best biological response parameters (total cell number, detached cells percentage, proliferation ratio) were obtained in the case of annealed Ta2O5 coatings with stoichiometric composition and the largest values of the SFE polar part and the of the fractional polarity.

  17. Comparison of amphipods Corophium insidiosum and C. orientale (Crustacea: Amphipoda) in sediment toxicity testing.

    Science.gov (United States)

    Prato, Ermelinda; Bigongiari, Nicola; Barghigiani, Corrado; Biandolino, Francesca

    2010-09-01

    The aim of this study was to compare the sensitivity of two Corophidae: Corophium orientale a standardized species and Corophium insidiosum a species more available in the Ionian sea (Southern Italy), in order to evaluate the suitability and applicability of C. insidiosum to sediment toxicity test. The sensitivity of the 2 species was compared through simultaneous bioassays: the 96-h static water-only toxicity test and a 10-day static sediment toxicity test. Sediment samples were collected in the Livorno harbour (Ligurian Sea). Both amphipods showed high sensitivity to reference toxicant and no significant differences were found between the two Corophiidae (t test; p > 0.05). Numerical Sediment Quality Guidelines (SQGs) have been used to relate the chemical concentrations of sediment samples to biological effects. Both amphipod species indicated the same sediment samples as potentially toxic according to chemical data. The results indicate that Corophium insidiosum would be suitable as an alternative test species to the recommended species C. orientale, in the development of sediment toxicity test.

  18. On the possibility of using biological toxicity tests to monitor the work of wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Zorić Jelena

    2008-01-01

    Full Text Available The aim of this study was to ascertain the possibility of using biological toxicity tests to monitor influent and effluent wastewaters of wastewater treatment plants. The information obtained through these tests is used to prevent toxic pollutants from entering wastewater treatment plants and discharge of toxic pollutants into the recipient. Samples of wastewaters from the wastewater treatment plants of Kragujevac and Gornji Milanovac, as well as from the Lepenica and Despotovica Rivers immediately before and after the influx of wastewaters from the plants, were collected between October 2004 and June 2005. Used as the test organism in these tests was the zebrafish Brachydanio rerio Hamilton - Buchanon (Cyprinidae. The acute toxicity test of 96/h duration showed that the tested samples had a slight acutely toxic effect on B. rerio, except for the sample of influent wastewater into the Cvetojevac wastewater treatment plant, which had moderately acute toxicity, indicating that such water should be prevented from entering the system in order to eliminate its detrimental effect on the purification process.

  19. In vitro susceptibility testing of Fonsecaea pedrosoi to antifungals

    Directory of Open Access Journals (Sweden)

    Catalina de BEDOUT

    1997-05-01

    Full Text Available Based on the difficulties experienced in the treatment of chromoblastomycosis, 12 primary human isolates of F. pedrosoi, were tested for their in vitro susceptibility to various antimycotics. We adapted the recommendations of the NCCLS for yeasts and followed the indications for mold testing from other authors in order to determine their MIC’s and the MLC’s. It was found that a significant proportion of the isolates were resistant to 3 of the 4 antimycotics tested, as revealed by high MIC values, as follows: 33% were resistant to amphotericin B (AMB, 58.3% to 5 fluocytosine (5 FC and 66.7% to fluconazole (FLU. Contrarywise, none of the isolates proved resistant to itraconazole (ITZ. Determination of the MLC’s revealed that a larger proportion of the isolates were not killed by AMB, 5 FC (91.7%, FLU (100% or even, ITZ (41.7%. These data indicate that it would be desirable to determine the susceptibility of F. pedrosoi before initiating therapy, in order to choose the more effective antifungal and avoid clinical failureTestes de suscetibilidade in vitro de Fonsecaea pedrosoi a antifúngicos Baseados nas dificuldades experimentadas no sucesso do tratamento da cromoblastomicose, 12 isolamentos humanos primários do F. pedrosoi foram examinados para a sua suscetibilidade in vitro aos vários antifúngicos. Nos adaptamos às recomendações da NCCLS feitas para leveduras e, seguimos as indicações para fungos filamentosos testados dadas por outros autores para as determinações dos MIC’s e dos MCLS. Nossos resultados mostraram que uma proporção significativa dos isolados testados foi resistente a três ou quatro dos antifúngicos experimentados, como revelaram os altos valores do MIC; assim, 33% dos isolados foram resistentes à anfotericina-B (AMB 58,3% à fluorocitosina (5FC e 66,7% ao fluconazole (FLU; pelo contrário, nenhum dos isolados examinados mostrou-se resistente ao itraconazole (ITZ. As determinações dos MLC revelaram que

  20. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    Science.gov (United States)

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

  1. Progress Toward Replacing Animals in Toxicity Testing for Cosmetics

    OpenAIRE

    Nye, Marisa B.

    2006-01-01

    In the 1980’s, animal rights activists successfully motivated the cosmetic industry to begin researching alternatives to animal tests. The European Union has taken action to stimulate development and validation of alternatives to animal testing through the Sixth and Seventh Amendments to the Cosmetics Directive. In this paper, I will briefly describe the history of the search for alternatives to animal testing for cosmetics. I will then discuss the progress that has been ma...

  2. Field Validation of Toxicity Tests to Evaluate the Potential for Beneficial Use of Produced Water

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Bidwell; Jonathan Fisher; Naomi Cooper

    2008-03-31

    This study investigated potential biological effects of produced water contamination derived from occasional surface overflow and possible subsurface intrusion at an oil production site along the shore of Skiatook Lake, Oklahoma. We monitored basic chemistry and acute toxicity to a suite of standard aquatic test species (fathead minnow-Pimephales promelas, Daphnia pulex, Daphnia magna, and Ceriodaphnia dubia) in produced water and in samples taken from shallow groundwater wells on the site. Toxicity identification evaluations and ion toxicity modeling were used to identify toxic constituents in the samples. Lake sediment at the oil production site and at a reference site were also analyzed for brine intrusion chemically and by testing sediment toxicity using the benthic invertebrates, Chironomus dilutus, and Hyallela azteca. Sediment quality was also assessed with in situ survival and growth studies with H. azteca and the Asian clam, Corbicula fluminea, and by benthic macroinvertebrate community sampling. The produced water was acutely toxic to the aquatic test organisms at concentrations ranging from 1% to 10% of the whole produced water sample. Toxicity identification evaluation and ion toxicity modeling indicated major ion salts and hydrocarbons were the primary mixture toxicants. The standardized test species used in the laboratory bioassays exhibited differences in sensitivity to these two general classes of contaminants, which underscores the importance of using multiple species when evaluating produced water toxicity. Toxicity of groundwater was greater in samples from wells near a produced water injection well and an evaporation pond. Principle component analyses (PCA) of chemical data derived from the groundwater wells indicated dilution by lake water and possible biogeochemical reactions as factors that ameliorated groundwater toxicity. Elevated concentrations of major ions were found in pore water from lake sediments, but toxicity from these ions was

  3. TOXICITY TESTING IN THE 21ST CENTURY: A VISION AND A STRATEGY

    DEFF Research Database (Denmark)

    Krewski, D.; Acosta, D.; Andersen, M.

    2010-01-01

    With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U. S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal...... on pharmacokinetic models for the given exposure condition. This practice would enhance human relevance of test results, and would cover several test agents, compared to traditional toxicological testing strategies. As all the tools that are necessary to implement the vision are currently available or in an advanced...... stage of development, the key prerequisites to achieving this paradigm shift are a commitment to change in the scientific community, which could be facilitated by a broad discussion of the vision, and obtaining necessary resources to enhance current knowledge of pathway perturbations and pathway assays...

  4. 40 CFR 797.1930 - Mysid shrimp acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... rate through each chamber and the concentration of the test substance in each chamber. The general... rate of dilution water. The loading shall not cause the dissolved oxygen concentration to fall below... guideline. (1) “Death” means the lack of reaction of a test organism to gentle prodding. (2) “Flow-through...

  5. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Science.gov (United States)

    2010-07-01

    ... young. (C) Any ephippia are produced by control animals. (v) The number of immobilized daphnids in each.... Dissolved oxygen concentration, pH, temperature, the concentration of test substance, and other water... during the test to determine any significant differences (p≤0.05) in immobilization and reproduction as...

  6. Toxicity evaluation of trap and skeet shooting targets to aquatic test species.

    Science.gov (United States)

    Baer, K N; Hutton, D G; Boeri, R L; Ward, T J; Stahl, R G

    1995-12-01

    : Large quantities of trap and skeet clay targets are used in shooting activities around the United States. For example, the number of targets used since 1970 has averaged approximately 560 million a year. A number of acute and chronic tests were performed to determine the toxicity of Remington Arms Company Blue Rock(®) trap and skeet target fragments upon selected freshwater and marine organisms. These studies were undertaken in support of an environmental impact study of trap and skeet shooting activities at a major gun club in the northeast United States. Targets were composed of approximately 67% dolomitic limestone, 32% petroleum pitch and 1% fluorescent aqueous paint (painted targets only). The majority of samples were painted, new targets obtained from the manufacturer and painted and aged targets collected around a shooting range. Additional tests were conducted using non-painted, new targets and leachates prepared from both painted, new and aged targets. Targets were crushed to small fragments and were either directly added to the test vessels at extremely high concentrations ranging from 670 to 600 000 mgl(-1) or used in leachate tests. In direct tests all target materials were essentially non-toxic to marine and freshwater organisms, except for the non-painted new targets which exhibited minimal acute toxicity to Daphnia magna (48 h EC 50=2200 mgl(-1)). In leachate tests, the leachate was not-toxic to mysid shrimp, the only organism tested. Additional samples of crushed targets were analysed for the presence of selected priority pollutants (EP toxicity test) and polycyclic aromatic hydrocarbons (PAHs). The targets did not exhibit the characteristics of toxicity as determined by the EP toxicity test but did contain substantial amounts of PAHs. However, results from new and aged targets suggest that PAH are tightly bound in the petroleum pitch and limestone matrix and are unlikely to be readily available in the environment. The potential impact of targets

  7. Assigning ethical weights to clinical signs observed during toxicity testing.

    Science.gov (United States)

    Ringblom, Joakim; Törnqvist, Elin; Hansson, Sven Ove; Rudén, Christina; Öberg, Mattias

    2017-01-01

    Reducing the number of laboratory animals used and refining experimental procedures to enhance animal welfare are fundamental questions to be considered in connection with animal experimentation. Here, we explored the use of cardinal ethical weights for clinical signs and symptoms in rodents by conducting trade-off interviews with members of Swedish Animal Ethics Committees in order to derive such weights for nine typical clinical signs of toxicity. The participants interviewed represent researchers, politically nominated political nominees and representatives of animal welfare organizations. We observed no statistically significant differences between these groups with respect to the magnitude of the ethical weights assigned, though the political nominees tended to assign lower weights. Overall, hunched posture was considered the most severe clinical sign and body weight loss the least severe. The ethical weights assigned varied considerably between individuals, from zero to infinite value, indicating discrepancies in prioritization of reduction and refinement. Cardinal ethical weights may be utilized to include both animal welfare refinement and reduction of animal use in designing as well as in retrospective assessment of animal experiments. Such weights may also be used to estimate ethical costs of animal experiments.

  8. Antioxidant pre-treatment prevents omeprazole-induced toxicity in an in vitro model of infectious gastritis

    Science.gov (United States)

    Kohler, Jonathan E.; Blass, Amy L.; Liu, Jingjing; Tai, Kaniza; Soybel, David I.

    2010-01-01

    Omeprazole is a mainstay of therapy for gastroesophageal reflux disease (GERD) and gastritis, and is increasingly used as an over-the-counter remedy for dyspepsia. Omeprazole acts by selectively oxidizing thiol targets in the gastric proton pump, but it also appears to be toxic to the gastric mucosa. We hypothesized that omeprazole toxicity is due to non-specific oxidation of cell structures other than the proton pump, and tested the efficacy of antioxidants to prevent omeprazole-induced toxicity in isolated rabbit gastric glands. Toxicity was measured by uptake and converstion of calcein-AM, following three hours of exposure to omeprazole and a non-selective thiol-oxidant, monochloramine. Intracellular concentration of Zn2+ and the capacity to maintain luminal acidity were monitored using the fluorescent reporters fluozin-3 and Lysosensor DND-160, respectively. Both omeprazole and monochloramine caused marked reduction in cell viability. The toxicity of omeprazole was independent of monochloramine toxicity. The thiol reducing agent dithiothreitol protected gastric glands from injury. The oxidant scavenger Vitamin C also protected, and did not impair the anti-secretory effects of omeprazole. Thus, omeprazole toxicity appears to be oxidative and preventable with antioxidant therapy, including Vitamin C. Vitamin C may be a safe and efficacious addition to treatments requiring the use of PPIs. PMID:20554018

  9. In Vitro Antimicrobial and Antiprotozoal Activities, Phytochemical Screening and Heavy Metals Toxicity of Different Parts of Ballota nigra

    Directory of Open Access Journals (Sweden)

    Najeeb Ullah

    2014-01-01

    Full Text Available The study was done to assess the phytochemicals (flavonoids, terpenoids, saponins, tannin, alkaloids, and phenol in different parts (root, stem, and leaves of Ballota nigra and correlated it to inhibition of microbes (bacteria and fungi, protozoan (Leishmania, and heavy metals toxicity evaluation. In root and stem flavonoids, terpenes and phenols were present in ethanol, chloroform, and ethyl acetate soluble fraction; these were found to be the most active inhibiting fractions against all the tested strains of bacteria, fungi, and leishmania. While in leaves flavonoids, terpenes, and phenols were present in ethanol, chloroform, and n-butanol fractions which were the most active fractions against both types of microbes and protozoan (leishmania in in vitro study. Ethanol and chloroform fractions show maximum inhibition against Escherichia coli (17 mm. The phytochemical and biological screenings were correlated with the presence of heavy metals in selected plant Ballota nigra. Cr was found above permissible value (above 1.5 mg/kg in all parts of the plant. Ni was above WHO limit in B. nigra root and leaves (3.35 ± 1.20 mg/kg and 5.09 ± 0.47 mg/kg, respectively. Fe was above permissible value in all parts of B. nigra (above 20 mg/kg. Cd was above permissible value in all parts of the plant (above 0.3 mg/kg. Pb was above WHO limit (above 2 mg/kg in all parts of Ballota nigra.

  10. Correlation of in vitro challenge testing with consumer use testing for cosmetic products.

    Science.gov (United States)

    Brannan, D K; Dille, J C; Kaufman, D J

    1987-01-01

    An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of cosmetic products. The challenge test involved inoculating product at four concentrations (30, 50, 70, and 100%) with microorganisms known to contaminate cosmetics. Elimination of these microorganisms at each concentration was followed over a 28-day period. The test was used to classify products as poorly preserved, marginally preserved, or well preserved. Consumer use testing was then used to determine whether the test predicted the risk of actual consumer contamination. Products classified by the challenge test as poorly preserved returned 46 to 90% contaminated after use. Products classified by the challenge test as well preserved returned with no contamination. Marginally preserved products returned with 0 to 21% of the used units contaminated. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products. PMID:3662517

  11. Revolution In Toxicity Testing And Risk Prediction For Chemicals In The Environment (ASA)

    Science.gov (United States)

    Addressing safety aspects of drugs and environmental chemicals relies extensively on animal testing; however, the quantity of chemicals needing assessment and challenges of species extrapolation require alternative approaches to traditional animal studies. Newer in vitro and in s...

  12. [Pulmonary function tests at different stages of toxic oil syndrome].

    Science.gov (United States)

    Martin Escribano, P; Fernandez Sanchez Alarcos, J M; Dominguez-Lozano, M J; Diaz de Atauri, J; Barbosa-Ayucar, C; Cantalapiedra, J A; Lopez Encuentra, A

    1984-01-01

    The toxic oil syndrome is a new multisystemic disease, caused by ingestion of adulterated olive oil; this oil had a part of rapeseed oil, which was denatured with aniline for industrial use, and then re-refined. It is estimated that 20,000 people were more or less affected, the mortality being 1.7%. There is no clear pathogenetic mechanism, but the most probable is the generation of free radicals, caused by anilides. The clinical picture began with fever, acute interstitial pneumonia, pruritus, exanthems, myalgias and eosinophilia. The main pathological findings were generalized endothelial lesions, septal oedema, mild inflammatory mononuclear infiltrates and hydropic degeneration of type I and II pneumocytes with desquamation of type I. The pneumonic syndrome had a favourable evolution, except in 5% of the patients who went into acute respiratory distress and suffered an important mortality. In 10% of the patients, a moderate hypoxaemia remained with normal chest film; in these cases, a transbronchial biopsy showed more severe endothelial lesions and, in some of these patients, it was possible to find clinical signs of pulmonary hypertension, which was moderate and did not improve with oxygen or vasoactive agents. The neurological symptomatology was progressive, leading to very severe muscular atrophy and, in some cases, to alveolar hypoventilation. The neuromyopathy, as the other clinical manifestations, improved slowly during the following months. A year after the onset, a pulmonary restriction with a low transfer factor of CO remained, and some patients had residual neuromyopathy and severe scleroderma-like lesions of the skin. (ABSTRACT TRUNCATED AT 250 WORDS)

  13. Recreating the seawater mixture composition of HOCs in toxicity tests with Artemia franciscana by passive dosing

    Energy Technology Data Exchange (ETDEWEB)

    Rojo-Nieto, E., E-mail: elisa.rojo@uca.es [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Smith, K.E.C. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark); Perales, J.A. [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Mayer, P. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark)

    2012-09-15

    The toxicity testing of hydrophobic organic compounds (HOCs) in aquatic media is generally challenging, and this is even more problematic for mixtures. The hydrophobic properties of these compounds make them difficult to dissolve, and subsequently to maintain constant exposure concentrations. Evaporative and sorptive losses are highly compound-specific, which can alter not only total concentrations, but also the proportions between the compounds in the mixture. Therefore, the general aim of this study was to explore the potential of passive dosing for testing the toxicity of a PAH mixture that recreates the mixture composition found in seawater from a coastal area of Spain, the Bay of Algeciras. First, solvent spiking and passive dosing were compared for their suitability to determine the acute toxicity to Artemia franciscana nauplii of several PAHs at their respective solubility limits. Second, passive dosing was applied to recreate the seawater mixture composition of PAHs measured in a Spanish monitoring program, to test the toxicity of this mixture at different levels. HPLC analysis was used to confirm the reproducibility of the dissolved exposure concentrations for the individual PAHs and mixtures. This study shows that passive dosing has some important benefits in comparison with solvent spiking for testing HOCs in aquatic media. These include maintaining constant exposure concentrations, leading to higher reproducibility and a relative increase in toxicity. Passive dosing is also able to faithfully reproduce real mixtures of HOCs such as PAHs, in toxicity tests, reproducing both the levels and proportions of the different compounds. This provides a useful approach for studying the toxicity of environmental mixtures of HOCs, both with a view to investigating their toxicity but also for determining safety factors before such mixtures result in detrimental effects.

  14. Application of leaching tests for toxicity evaluation of coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Tsiridis, V.; Samaras, P.; Kungolos, A.; Sakellaropoullos, G.P. [Technological Educational Institute for West Macedonia, Kozani (Greece). Dept. for Pollution Control Technology

    2006-08-15

    The toxic properties of coal fly ash samples obtained from various coal combustion power plants were evaluated in this work using physicochemical analyses and bioassays. Physicochemical analyses showed that heavy metals present in solid samples included Cr, Cu, Mn, Ni, Pb, and Zn. The results of the chemical analysis of eluates deduced by the application of standard leaching tests according to EN 12457-2 and Toxicity Characteristic Leaching Procedure (TCLP) methods indicated that the compounds contained in fly ashes could potentially be transferred to the liquid phase depending upon the leaching method used. Heavy metal concentrations were higher in TCLP eluates, indicating that the initial pH value of the leaching medium significantly affected the transfer of these elements to the liquid phase. Tests conducted with the photobacterium Vibrio fischeri (Microtox test), the crustacean Daphnia magna, and the rotifer Brachionus calyciflorus were used to assess toxicity of eluates obtained by both leaching tests. Daphnia magna was the most sensitive test organism. The EN 12457-2 method proved to be more reliable for toxicity evaluation of eluates. In contrast, the TCLP method showed some interference owing to acetic acid toxicity, and precipitation occurred after pH adjustment of eluates from acid to neutral range. The toxicity of both fly ashes and the corresponding solid leaching residues of EN 12457-2 and TCLP leaching tests was also measured using the Microtox Basic Solid phase Test. The results generated with this bioassay indicated that toxicity was greatly influenced by the pH status of the solid samples.

  15. In Vitro Susceptibility Test of Different Clinical Isolates against Ceftriaxone

    Directory of Open Access Journals (Sweden)

    Syed Hakim Masood

    2010-06-01

    Full Text Available Objectives: Because of the prevailing penicillin resistance in microorganisms, broad spectrum cephalosporins are used empirically specially in developing countries. The aim of this study is to determine the susceptibility pattern of different gram positive and gram negative pathogens against third generation cephalosporin-ceftriaxone to explore the existing effectiveness of this antibiotic.Methods: 180 clinical isolates of different gram positive and gram negative pathogens including P.mirabilis, S. typhi P.aeruginosa, E. coli, S. aureus and Klebsiella were collected from blood and urine samples of in-patients. 30 isolates of all species were tested against each of six brands of ceftriaxone using in vitro sensitivity tests by disc diffusion method (NCCLS criteria. The susceptibility limit was ≥21 mm zone of inhibition, while moderately susceptible was considered at 20-14 mm, and those isolates which showed >13 mm or no zone of inhibition were resistant to this antibacterial drug.Results: Ceftriaxone was found most effective against S. aureus. While 96.1% of the isolates showed susceptibility towards ceftriaxone, followed by E. coli (95%, P. aeruginosa (92.7%, K. pneumonia (89.4% and S. typhi (87.2%. P. mirabilis showed lowest susceptibility amongst all the test organisms (83.8%.Conclusion: Ceftriaxone can be used as a drug of choice in infections caused by S. aureus, E. coli, P. aurigenosa, K. pneumonia and S. typhi. However, it should be used with other antimicrobial agents in order to increase its effectiveness against P. mirabilis.

  16. In Vitro Toxicity of Epigallocatechin Gallate in Rat Liver Mitochondria and Hepatocytes

    Directory of Open Access Journals (Sweden)

    Otto Kucera

    2015-01-01

    Full Text Available Epigallocatechin-3-gallate (EGCG is the main compound of green tea with well-described antioxidant, anti-inflammatory, and tumor-suppressing properties. However, EGCG at high doses was reported to cause liver injury. In this study, we evaluated the effect of EGCG on primary culture of rat hepatocytes and on rat liver mitochondria in permeabilized hepatocytes. The 24-hour incubation with EGCG in concentrations of 10 μmol/L and higher led to signs of cellular injury and to a decrease in hepatocyte functions. The effect of EGCG on the formation of reactive oxygen species (ROS was biphasic. While low doses of EGCG decreased ROS production, the highest tested dose induced a significant increase in ROS formation. Furthermore, we observed a decline in mitochondrial membrane potential in cells exposed to EGCG when compared to control cells. In permeabilized hepatocytes, EGCG caused damage of the outer mitochondrial membrane and an uncoupling of oxidative phosphorylation. EGCG in concentrations lower than 10 μmol/L was recognized as safe for hepatocytes in vitro.

  17. In Vitro Toxicity of Epigallocatechin Gallate in Rat Liver Mitochondria and Hepatocytes

    Science.gov (United States)

    Kucera, Otto; Mezera, Vojtech; Moravcova, Alena; Endlicher, Rene; Lotkova, Halka; Drahota, Zdenek; Cervinkova, Zuzana

    2015-01-01

    Epigallocatechin-3-gallate (EGCG) is the main compound of green tea with well-described antioxidant, anti-inflammatory, and tumor-suppressing properties. However, EGCG at high doses was reported to cause liver injury. In this study, we evaluated the effect of EGCG on primary culture of rat hepatocytes and on rat liver mitochondria in permeabilized hepatocytes. The 24-hour incubation with EGCG in concentrations of 10 μmol/L and higher led to signs of cellular injury and to a decrease in hepatocyte functions. The effect of EGCG on the formation of reactive oxygen species (ROS) was biphasic. While low doses of EGCG decreased ROS production, the highest tested dose induced a significant increase in ROS formation. Furthermore, we observed a decline in mitochondrial membrane potential in cells exposed to EGCG when compared to control cells. In permeabilized hepatocytes, EGCG caused damage of the outer mitochondrial membrane and an uncoupling of oxidative phosphorylation. EGCG in concentrations lower than 10 μmol/L was recognized as safe for hepatocytes in vitro. PMID:25918582

  18. Evaluation of alamar blue reduction for the in vitro assay of hepatocyte toxicity.

    Science.gov (United States)

    Slaughter, M R; Bugelski, P J; O'Brien, P J

    1999-01-01

    Alamar Blue (AB) reduction is a promising new in vitro assay which is simple to conduct and amenable to repeated measurements and high-throughput screening; however, evaluation with hepatocytes has not been reported. Accordingly, we compared AB reduction with established markers of hepatocyte viability and cell density. Primary rat hepatocytes were allowed to adhere to collagen-coated 96-well plates, then exposed for 16 hours to culture medium, 0.7% dimethyl sulfoxide (DMSO) in medium, 500 mum CCl(4), 500 mum eugenol or 15 or 150 mum of a novel substituted indoline (the latter three in medium with 0.7% DMSO; medium also contained hydrocortisone during exposure period). Using a spectrophotometric plate reader, AB reduction was compared with lactate dehydrogenase release (LDH) release, neutral red (NR) uptake, total protein (TP) and cell seed density. AB reduction showed a linear relationship and good correlation with NR uptake, LDH release, TP and cell density. AB assay precision varied with cell density, but was similar to other assays in cytotoxicity screening. Good correlation with cell density indicates AB to have the potential for assessment of hepatocyte proliferation. From the results reported here, we recommend further evaluation and optimization of a protocol for application of AB reduction as a test for cytotoxicity and proliferation in primary hepatocyte cultures.

  19. Chapter 31: Common in vitro tests for allergy and immunology.

    Science.gov (United States)

    Makhija, Melanie; O'Gorman, Maurice R G

    2012-01-01

    Allergen-specific IgE antibody is the most commonly ordered in vitro test in the practice of allergy and is used to diagnose type I hypersensitivity reactions to foods or reactivity to aeroallergens in patients with relative contraindications to skin-prick testing such as dermatographism. The Phadebas radioallergosorbent test (RAST; Pharmacia, Uppsala, Sweden) was the first assay reported for the detection of the allergen-specific IgE antibody. In a RAST, antigen (allergen) is bound to a solid phase, such as a paper disk, and then incubated with human serum. A buffer wash removes unbound serum proteins, and radiolabeled anti-human IgE is added to detect bound IgE, if present. The results are reported in arbitrary units of IgE per milliliter of serum. The term RAST was originally a brand name but it is now often used colloquially (and incorrectly) to describe any in vitro assay for allergen-specific IgE. Total serum IgE can be measured and is helpful in determining atopic presentations such as in allergic bronchopulmonary aspergillosis or in patients with persistent asthma who are candidates for monoclonal anti-IgE antibody therapy with, omalizumab. In patients with recurrent bacterial infections of the sinopulmonary tract, the basic humoral immune system testing includes measuring quantitative immunoglobulins (IgG, IgA, and IgM) and comparing them to age-matched normal ranges. Most clinical laboratories use nephelometry to measure immunoglobulin levels quantitatively. Nephelometry detects either the rate or the end point of soluble immune complex formation (the IgG in sera complexes with an anti-IgG antibody forming a classic immunoprecipitation reaction) by monitoring the scatter of transmitted light. The most common method for the screening of cellular immunodeficiency involved the measurement of the absolute and relative representation of the major lymphocyte subsets, T-cells, T-helper cells, T-cytotoxic cells, B-cells and NK-cells.

  20. Glycerol monolaurate and dodecylglycerol effects on Staphylococcus aureus and toxic shock syndrome toxin-1 in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Ying-Chi Lin

    Full Text Available Glycerol monolaurate (GML, a 12 carbon fatty acid monoester, inhibits Staphylococcus aureus growth and exotoxin production, but is degraded by S. aureus lipase. Therefore, dodecylglycerol (DDG, a 12 carbon fatty acid monoether, was compared in vitro and in vivo to GML for its effects on S. aureus growth, exotoxin production, and stability.Antimicrobial effects of GML and DDG (0 to 500 microg/ml on 54 clinical isolates of S. aureus, including pulsed-field gel electrophoresis (PFGE types USA200, USA300, and USA400, were determined in vitro. A rabbit Wiffle ball infection model assessed GML and DDG (1 mg/ml instilled into the Wiffle ball every other day effects on S. aureus (MN8 growth (inoculum 3x10(8 CFU/ml, toxic shock syndrome toxin-1 (TSST-1 production, tumor necrosis factor-alpha (TNF-alpha concentrations and mortality over 7 days. DDG (50 and 100 microg/ml inhibited S. aureus growth in vitro more effectively than GML (p<0.01 and was stable to lipase degradation. Unlike GML, DDG inhibition of TSST-1 was dependent on S. aureus growth. GML-treated (4 of 5; 80% and DDG-treated rabbits (2 of 5; 40% survived after 7 days. Control rabbits (5 of 5; 100% succumbed by day 4. GML suppressed TNF-alpha at the infection site on day 7; however, DDG did not (<10 ng/ml versus 80 ng/ml, respectively.These data suggest that DDG was stable to S. aureus lipase and inhibited S. aureus growth at lower concentrations than GML in vitro. However, in vivo GML was more effective than DDG by reducing mortality, and suppressing TNF-alpha, S. aureus growth and exotoxin production, which may reduce toxic shock syndrome. GML is proposed as a more effective anti-staphylococcal topical anti-infective candidate than DDG, despite its potential degradation by S. aureus lipase.

  1. Effect of different in vitro culture extracts of black pepper (Piper nigrum L.) on toxic metabolites-producing strains.

    Science.gov (United States)

    Ahmad, Nisar; Abbasi, Bilal Haider; Fazal, Hina

    2016-03-01

    In the present study, the effect of different in vitro cultures (callus, in vitro shoots) and commercially available peppercorn extract was investigated for its activity against toxic metabolite-producing strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Candida albicans). These in vitro cultures were extracted with ethanol, hexane, and chloroform, and the antipathogenic activity was determined by well-diffusion method. Hexane extract of callus showed 22 mm zone of inhibition against B. cereus, 23 mm against S. aureus, while regenerated shoots and seeds have shown 24.3 and 26 mm zones of inhibition. The ethanolic extracts of regenerated Piper shoots have shown 25 mm activity against S. aureus, 21 mm against B. cereus, and 16 mm in the case of C. albicans in comparison with standard antibiotics. Peppercorn extracts in chloroform and ethanol had shown activities against B. cereus (23.6 mm) and B. subtilis (23.5 mm). During in vitro organogenesis and morphogenesis, cells and tissues produced a comparable phytochemicals profile like mother plant. Morphogenesis is critically controlled by the application of exogenous plant-growth regulators. Such addition alters the hormonal transduction pathways, and cells under in vitro conditions regenerate tissues, which are dependant on the physiological state of cells, and finally enhance the production of secondary metabolites. To the best of our knowledge, this is the first report to compare the antimicrobial potential of in vitro regenerated tissues and peppercorn with standard antibiotics. In conclusion, most of the extracts showed pronounced activities against all the pathogenic microbes. This is a preliminary work, and the minimum inhibitory concentration values needs to be further explored. Regenerated tissues of P. nigrum are a good source of biologically active metabolites for antimicrobial activities, and callus culture presented itself as

  2. NMSBA: Aken Technologies Final Report: Toxicity Testing of Liquidoff

    Energy Technology Data Exchange (ETDEWEB)

    Ruffing, Anne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jensen, Travis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Strickland, Lucas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    To determine the effect of Liquidoff on bacteria, three bacterial strains were tested: Escherichia coli DH5α, Synechococcus sp. PCC 7002, and Synechococcus elongatus PCC 7942. E. coli DH5α is a Gram-negative, aerobic bacterium that is often found in normal gut flora and is commonly used the laboratory due to its fast growth rate. Synechococcus sp. PCC 7002 and S. elongatus PCC 7942 are Gram-negative, aquatic, autophototrophic cyanobacteria. Synechococcus sp. PCC 7002 is a marine cyanobacterium isolated from ‘fish pens’ on Magueyes Island, Puerto Rico in 1962, while S. elongatus PCC 7942 is a freshwater cyanobacterium. It should be noted that no Gram-positive bacterium was tested in this study.

  3. Toxicity evaluation of ethanol treatment during in vitro maturation of porcine oocytes and subsequent embryonic development following parthenogenetic activation and in vitro fertilization.

    Science.gov (United States)

    Lee, Sanghoon; Kim, Eunhye; Hyun, Sang-Hwan

    2014-11-01

    Ethanol is frequently used as a solvent in several techniques for in vitro production (IVP). It is also used for the parthenogenetic activation (PA) of oocytes. Although a number of studies have suggested that ethanol has detrimental effects on fibroblasts and neuronal cells, little attention has been paid to the effects of ethanol on porcine oocytes. Thus, the aim of this study was to evaluate the effects of the addition of ethanol to in vitro maturation (IVM) medium. We investigated the effects of ethanol (0, 1 and 3%) on the following parameters: nuclear maturation, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels, and subsequent embryonic development following PA and in vitro fertilization (IVF). After 44 h of IVM, the 3% group showed a significant (Pethanol group showed significantly (Pethanol group had significantly (P1% ethanol during IVM exerts a toxic effect on the developmental potential of PA and IVF porcine embryos by decreasing the intracellular GSH level, thereby increasing the intracellular ROS level and upregulating the expression of apoptosis‑related genes.

  4. Development of a Chronic Toxicity Testing Method for Daphnia pulex

    Science.gov (United States)

    2015-08-01

    Protection Agency YCT yeast , cereal leaves, and trout chow (from a commercial vendor) ERDC/EL SR-15-5 1 1 Introduction The chronic...cm with Milli-Q water) • YCT ( yeast , cereal leaves, trout chow) • ALG- algae, Selenastrum capricornutum(from a commercial vendor); also known as...screened holes (10 replicate beakers for each test concentration) • One modified Zumwalt box (Figures A1-A3) with water exchange system (optional) • One

  5. Dispersed oil toxicity tests with biological species indigenous to the Gulf of Mexico. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fucik, K.W.; Carr, K.A.; Balcom, B.J.

    1994-08-01

    Static and flowthrough aquatic acute toxicity testing protocols were utilized on eggs and larvae of seven commercially important invertebrates and fishes from the Gulf of Mexico. Test organisms were exposed to Central and Western Gulf oils, dispersed oil, and Corexit 9527. Species included brown shrimp (Penaeus aztecus), white shrimp (Penaeus setiferus), blue crab (Callinectes sapidus), eastern oyster (Crassostrea virginica), red drum (Sciaenops ocellatus), inland silverside (Menidia berylina), and spot (Leiosomus xanthurus). Atlantic menhaden (Brevoortia tyrannus) was also tested because gulf menhaden were not available. Mysids (Mysidopsis bahia) were evaluated as part of a chronic toxicity assessment.

  6. Acute aquatic toxicity of heavy fuel oils. Summary of relevant test data

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.; Djemel, N.; Eadsforth, C.V.; King, D.; Parkerton, T.; Paumen, M.L.; Dmytrasz, B.

    2011-12-15

    This report describes the experimental procedures and results obtained in acute ecotoxicity tests on several heavy fuel oil (HFO) samples. Water accommodated fractions (WAFs) of these samples were tested for toxicity to the rainbow trout (Oncorhynchus mykiss), the crustacean zooplankter (Daphnia magna) and green algae (Selenastrum capricornutum). These results assist in determining the environmental hazard from heavy fuel oil.

  7. Acute and chronic aquatic toxicity of aromatic extracts. Summary of relevant test data

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.; Djemel, N.; Eadsforth, C.V.; King, D.; Parkerton, T.; Leon Paumen, M.; Dmytrasz, B.; Del Castillo, F.

    2013-09-15

    This report describes the experimental procedures and the results obtained in acute and chronic ecotoxicity tests on several aromatic extracts samples. The samples were tested for toxicity to the rainbow trout (Oncorhynchus mykiss), the crustacean zooplankter, Daphnia magna and the algae, Selenastrum capricornutum using water accommodated fractions. These results assist in determining the environmental hazard posed by aromatic extracts.

  8. Large Dataset of Acute Oral Toxicity Data Created for Testing in Silico Models (ASCCT meeting)

    Science.gov (United States)

    Acute toxicity data is a common requirement for substance registration in the US. Currently only data derived from animal tests are accepted by regulatory agencies, and the standard in vivo tests use lethality as the endpoint. Non-animal alternatives such as in silico models are ...

  9. In vitro toxicity of local anaesthetics and corticosteroids on supraspinatus tenocyte viability and metabolism

    Directory of Open Access Journals (Sweden)

    Clayton W. Nuelle

    2017-01-01

    Conclusion: This data confirms that peritendinous injection of commonly used local anaesthetics and corticosteroids results in significant supraspinatus tenotoxicity in vitro. Further in vivo studies are required before making definitive clinical recommendations.

  10. In vitro vaccine potency testing: a proposal for reducing animal use for requalification testing.

    Science.gov (United States)

    Brown, K; Stokes, W

    2012-01-01

    This paper proposes a program under which the use of animals for requalification of in vitro potency tests could be eliminated. Standard References (USDA/CVB nomenclature) would be developed, characterized, stored and monitored by selected reference laboratories worldwide. These laboratories would employ scientists skilled in protein and glycoprotein chemistry and equipped with state-of-the-art instruments for required analyses. After Standard References are established, the reference laboratories would provide them to the animal health industry as "gold standards". Companies would then establish and validate a correlation between the Standard Reference and the company Master Reference (USDA/CVB nomenclature) using an internal in vitro assay. After this correlation is established, the company could use the Standard References for qualifying, monitoring and requalifying company Master References without the use of animals. Such a program would eliminate the need for animals for requalification of Master References and the need for each company to develop and validate a battery of Master Reference Monitoring assays. It would also provide advantages in terms of reduced costs and reduced time for requalification testing. As such it would provide a strong incentive for companies to develop and use in vitro assays for potency testing.

  11. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier

    2016-01-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from...... nine countries participated in these ring-tests. Survival and reproduction were evaluated in L. stagnalis exposed to cadmium, tributyltin, prochloraz and trenbolone according to an OECD draft Test Guideline. In total, 49 datasets were analysed to assess the practicability of the proposed experimental...... statistical analysis, the optimal test duration was established and the most sensitive and cost-effective reproduction toxicity endpoint was identified, to be used as the core endpoint. This validation process and the resulting optimized protocol were used to consolidate the OECD Test Guideline...

  12. Inhalation method for delivery of nanoparticles to the Drosophila respiratory system for toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Posgai, Ryan; Ahamed, Maqusood [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Hussain, Saber M. [Applied Biotechnology Branch, Human Effectiveness Directorate Air Force Research Laboratory/RHBP, Wright-Patterson Air Force Base, OH, 45433 (United States); Rowe, John J. [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Nielsen, Mark G., E-mail: Mark.Nielsen@notes.udayton.edu [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States)

    2009-12-20

    The growth of the nanotechnology industry and subsequent proliferation of nanoparticle types present the need to rapidly assess nanoparticle toxicity. We present a novel, simple and cost-effective nebulizer-based method to deliver nanoparticles to the Drosophila melanogaster respiratory system, for the purpose of toxicity testing. FluoSpheres (registered) , silver, and CdSe/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable of functioning with a wide range of nanoparticle types and sizes. Red fluorescent CdSe/ZnS nanoparticles were successfully delivered to the fly respiratory system, as visualized by fluorescent microscopy. Silver coated and uncoated nanoparticles were delivered in a toxicity test, and induced Hsp70 expression in flies, confirming the utility of this model in toxicity testing. This is the first method developed capable of such delivery, provides the advantage of the Drosophila health model, and can serve as a link between tissue culture and more expensive mammalian models in a tiered toxicity testing strategy.

  13. Development of marine sediment bioassays and toxicity tests for monitoring and regulation in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Thain, J.; Matthiessen, P.

    1995-12-31

    There is a need in Europe and elsewhere for a broad suite of whole-sediment bioassays and toxicity tests which can be used for routine monitoring and assessment of the marine environment and for evaluating the toxic effects of chemicals which may find their way into sediments. Until recently, few European species had been incorporated into such tests but the availability of suitable methodologies is now increasing rapidly. Perhaps the most important recent activity in this area consisted of an international ring test of acute sediment toxicity test methods which was organized by the Oslo and Paris Commissions in 1993, using up to 4 offshore chemicals as test materials. It evaluated the performance of 4 acute (5--10 day) tests involving: the sea urchin Echinocardium cordatum, the bivalve mollusc Abra alba, the amphipod crustacean Corophium volutator, and the polychaete worm Arenicola marina. The ring test concluded that the C. volutator test was the most appropriate for evaluating offshore chemicals, but all these methods are now widely used in Europe, both as toxicity tests and as bioassays. For example, the A. marina procedure (which has both lethal and sublethal endpoints), in combination with the C. volutator method, is now routinely used in the UK for monitoring the toxicity of estuarine sediments. Further activities are in progress. Perhaps the most important is the development of chronic marine sediment tests and bioassays which can be used to assess the long-term effects of the many sedimentary contaminants which are able to persist in this type of habitat and possibly cause delayed effects on the growth and reproduction, etc. of benthic fauna.

  14. Consensus report on the future of animal-free systemic toxicity testing.

    Science.gov (United States)

    Leist, Marcel; Hasiwa, Nina; Rovida, Costanza; Daneshian, Mardas; Basketter, David; Kimber, Ian; Clewell, Harvey; Gocht, Tilman; Goldberg, Alan; Busquet, Francois; Rossi, Anna-Maria; Schwarz, Michael; Stephens, Martin; Taalman, Rob; Knudsen, Thomas B; McKim, James; Harris, Georgina; Pamies, David; Hartung, Thomas

    2014-01-01

    Since March 2013, animal use for cosmetics testing for the European market has been banned. This requires a renewed view on risk assessment in this field. However, in other fields as well, traditional animal experimentation does not always satisfy requirements in safety testing, as the need for human-relevant information is ever increasing. A general strategy for animal-free test approaches was outlined by the US National Research Council`s vision document for Toxicity Testing in the 21st Century in 2007. It is now possible to provide a more defined roadmap on how to implement this vision for the four principal areas of systemic toxicity evaluation: repeat dose organ toxicity, carcinogenicity, reproductive toxicity and allergy induction (skin sensitization), as well as for the evaluation of toxicant metabolism (toxicokinetics) (Fig. 1). CAAT-Europe assembled experts from Europe, America and Asia to design a scientific roadmap for future risk assessment approaches and the outcome was then further discussed and refined in two consensus meetings with over 200 stakeholders. The key recommendations include: focusing on improving existing methods rather than favoring de novo design; combining hazard testing with toxicokinetics predictions; developing integrated test strategies; incorporating new high content endpoints to classical assays; evolving test validation procedures; promoting collaboration and data-sharing of different industrial sectors; integrating new disciplines, such as systems biology and high throughput screening; and involving regulators early on in the test development process. A focus on data quality, combined with increased attention to the scientific background of a test method, will be important drivers. Information from each test system should be mapped along adverse outcome pathways. Finally, quantitative information on all factors and key events will be fed into systems biology models that allow a probabilistic risk assessment with flexible

  15. Sperm toxicity testing: UK best practice guideline from the Association of Biomedical Andrologists.

    Science.gov (United States)

    Long, S; Woodward, B; Tomlinson, M

    2018-02-09

    In order to ensure the quality and integrity of diagnostic semen analysis results, materials used should be tested to ensure that they do not interfere with sperm function. As a toxicity test, complex sperm function testing may be considered controversial, since the fertilizing capacity of single sperm can never be assured. In preference, sperm motility offers a unique means of assessing the toxicity of reagents and materials before they are used in routine practice. Motility is the semen parameter most likely to be influenced by the external environment. Indeed, it is the main reason that laboratories insist on supplying their own approved specimen containers and ensuring that patients, as far as possible, adhere to strict conditions for sample collection and transport prior to testing. This differs to other indirect tests of toxicity such as the mouse embryo assay, whereby the rate of mouse pre-implantation embryo development to the blastocyst stage is compared. This guideline is aimed at health care scientists who deal with andrology in both general pathology and specialised fertility laboratories, and provides a model approach to sperm toxicity testing. For assisted reproduction clinics, the same methodology can be used to test any consumables that are used for sperm processing, and as an indirect guide for any consumables that come into direct contact with oocytes and pre-implantation embryos.

  16. New animal-free concepts and test methods for developmental toxicity and peripheral neurotoxicity.

    Science.gov (United States)

    Leist, Marcel

    2017-11-01

    The complex toxicological fields of repeat dose organ toxicity (RDT) and developmental and reproductive toxicity (DART) still require new concepts and approaches to achieve a fully animal-free safety assessment of chemicals. One novel approach is the generation of relevant human cell types from pluripotent stem cells, and the use of such cells for the establishment of phenotypic test methods. Due to their broad endpoints, such tests capture multiple types of toxicants, i.e. they are a readout for the activation of many adverse outcome pathways (AOPs). The 2016 Lush Science Prize was awarded for the development of one such assay, the PeriTox test, which uses human peripheral neurons generated from stem cells. The assay endpoints measure various cell functions, and these give information on the potential neurotoxicity and developmental neurotoxicity hazard of test compounds. The PeriTox test method has a high predictivity and sensitivity for peripheral neurotoxicants, and thus addresses the inherent challenges in pesticide testing and drug development. Data from the test can be obtained quickly and at a relatively high-throughput, and thus, the assay has the potential to replace animal-based safety assessment during early product development or for screening potential environmental toxicants. 2017 FRAME.

  17. Use of standard effluent toxicity tests for protection of endangered and threatened species

    Energy Technology Data Exchange (ETDEWEB)

    Henke, C.E.; Dwyer, F.J.; Ingersoll, C.G.; Mount, D.R. [National Biological Service, Columbia, MO (United States); Mayer, F.L. [Environmental Protection Agency, Gulf Breeze, FL (United States)

    1995-12-31

    Water quality criteria and many other environmental assessment tools are based on the results of laboratory toxicity tests. For a variety of reasons, these tests are typically conducted using one of several common laboratory species; results from these tests are then extrapolated with the intention of providing protection for other species not tested directly. This surrogate species approach is particularly necessary for threatened and endangered (listed) species, for which direct toxicity testing is often impractical. However, without direct knowledge of listed species sensitivity, it is not possible to be certain whether these species are adequately protected by current environmental practices. Moreover, the level of protection intended by water quality criteria (e.g., 95% of species) may not be sufficient to meet the requirements of the Endangered Species Act. The authors conducted short-term chronic toxicity tests using Ceriodaphnia dubia and fathead minnows and two listed species, bonytail chub and Colorado squawfish. Methods for Ceriodaphnia dubia and fathead minnow tests were as described by USEPA for effluent testing under the NPDES program; tests with listed species were patterned after the fathead minnow test procedures. Tests were conducted with; (1) ammonia, (2) carbaryl, and (3) a mixture of carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin. Preliminary data analysis indicates that the two listed species respond in a similar manner as the fathead minnow. The sensitivity of listed species to contaminant exposures and implications for regulatory procedures will be discussed.

  18. A Lymnaea stagnalis Embryo Test for Toxicity Bioindication of Acidification and Ammonia Pollution in Water

    Directory of Open Access Journals (Sweden)

    Robert Mazur

    2016-07-01

    Full Text Available The paper presents a study leading to a new acute toxicity test on embryonic and juvenile organisms of the great pond snail (Lymnaea stagnalis Linnaeus. Sulfuric acid, nitric acid, and ammonium hydroxide were used as waterborne toxicants in laboratory experiments. The exposure time was 24 h. Tests were conducted in 5–10 replications for each toxicant. The toxicity of the substances was classified according to different scales and the test’s sensitivity was compared to that of the commonly used bioindicator Daphnia magna Straus. The assessment of toxicity impact was supported by microscopic observations. The probit method was used as a parametric statistical procedure to estimate LC50 and the associated 95% confidence interval. Our study showed that the early developmental stages of Lymnaea stagnalis are very sensitive bioindicators, making it possible to detect even very low levels of the above-mentioned water toxicants. The highest toxicity is shown by ammonium hydroxide with LC50/24h values, respectively, 24.27 for embryos and 24.72 for juvenile forms, and the lowest is shown by nitric acid ions with LC50/24h values, respectively, 105.19 for embryos and 170.47 for juvenile forms. It is highly cost-effective due to simple and efficient breeding and the small size of the organisms in the bioassay population. Compared with Daphnia magna, relatively low concentrations of toxicants caused a lethal effect on embryonic and juvenile organisms of the great pond snail. Owing to their common occurrence and sensitivity, early developmental forms of Lymnaea stagnalis can be a valuable new tool in biomonitoring of the freshwater environment.

  19. Development of an in vitro Endotoxin Test for Monoolein–Water ...

    African Journals Online (AJOL)

    Erah

    vitro endotoxin test (LAL test) for water- insoluble gel products. Since our research group is currently developing monoolein–water liquid crystalline gels of gentamycin for use as bioresorbable implants for the treatment of chronic osteomyelitis [10-12], we set out to develop an in vitro test method for endotoxin in this.

  20. Epigallocatechin-3-gallate counters cisplatin toxicity of rat testes.

    Science.gov (United States)

    Fouad, Amr A; Qutub, Hatem O; Fouad, Abo Elyazied A; Audeh, Ahmed M; Al-Melhim, Walid N

    2017-12-01

    Epigallocatechin-3-gallate (EG), the main active flavonoid in green tea, has well-known anti-inflammatory, antioxidant, and anti-apoptotic activities. The EG protection against testicular injury induced by cisplatin was studied in Sprague-Dawley rats. Cisplatin (10 mg/kg, i.p) was given as a single injection to rats. EG was given at 40 and 80 mg/kg/day, i.p., for 5 days, starting the same day of cisplatin insult. Serum testosterone, and testicular malondialdehyde, total antioxidant status, nitric oxide, interleukin-6, interleukin-1β, cytochrome C, Bax/Bcl-2 ratio, and caspase-3 were measured. In addition, testicular histopathological examination and immunohistochemical expression of testicular tumour necrosis factor-α were evaluated. Cisplatin, compared to the control, significantly decreased serum testosterone (6.48 ± 0.7 vs. 50.8 ± 4.91 ng/10 mL), and testicular tissue antioxidant status (17.3 ± 1.21 vs. 64.12 ± 5.4 μmol/g), and significantly increased interleukin-6 (85.81 ± 6.11 vs. 38.2 ± 2.79 pg/100 mg), interleukin-1β (98.09 ± 8.31 vs. 32.52 ± 2.08 pg/100 mg), malondialdehyde (74.5 ± 5.88 vs. 23.8 ± 1.91 nmol/g), nitric oxide (104.98 ± 8.5 vs. 52.68 ± 5.12 nmol/100 mg), cytochrome C (5.97 ± 0.33 vs. 1.6 ± 0.99 ng/mg protein), Bax/Bcl-2 ratio (4.01 ± 0.38 vs. 0.71 ± 0.0), and caspase-3 (3.2 ± 0.21 vs. 0.98 ± 0.08 O.D. 405 nm) in rat testes. EG (40 and 80 mg/kg, respectively) caused significant increases of serum testosterone (33.9 ± 2.89 and 47.88 ± 4.4 ng/10 mL), and testicular antioxidant status (47.1 ± 3.92 and 58.22 ± 3.58 μmol/g), and significant decreases of interleukin-6 (57.39 ± 4.2 and 48.18 ± 3.98 pg/100 mg), interleukin-1β (65.12 ± 5.88 and 41.96 ± 3.51 pg/100 mg), malondialdehyde (42.3 ± 3.9 and 28.67 ± 2.49 nmol/g), nitric oxide (70.6 ± 6.79 and 61.31

  1. In vitro surfactant structure-toxicity relationships: implications for surfactant use in sexually transmitted infection prophylaxis and contraception.

    Directory of Open Access Journals (Sweden)

    Ângela S Inácio

    Full Text Available BACKGROUND: The need for woman-controlled, cheap, safe, effective, easy-to-use and easy-to-store topical applications for prophylaxis against sexually transmitted infections (STIs makes surfactant-containing formulations an interesting option that requires a more fundamental knowledge concerning surfactant toxicology and structure-activity relationships. METHODOLOGY/PRINCIPAL FINDINGS: We report in vitro effects of surfactant concentration, exposure time and structure on the viability of mammalian cell types typically encountered in the vagina, namely, fully polarized and confluent epithelial cells, confluent but non-polarized epithelial-like cells, dendritic cells, and human sperm. Representatives of the different families of commercially available surfactants--nonionic (Triton X-100 and monolaurin, zwitterionic (DDPS, anionic (SDS, and cationic (C(nTAB (n = 10 to 16, C(12PB, and C(12BZK--were examined. Triton X-100, monolaurin, DDPS and SDS were toxic to all cell types at concentrations around their critical micelle concentration (CMC suggesting a non-selective mode of action involving cell membrane destabilization and/or destruction. All cationic surfactants were toxic at concentrations far below their CMC and showed significant differences in their toxicity toward polarized as compared with non-polarized cells. Their toxicity was also dependent on the chemical nature of the polar head group. Our results suggest an intracellular locus of action for cationic surfactants and show that their structure-activity relationships could be profitably exploited for STI prophylaxis in vaginal gel formulations. The therapeutic indices comparing polarized epithelial cell toxicity to sperm toxicity for all surfactants examined, except C(12PB and C(12BZK, does not justify their use as contraceptive agents. C(12PB and C(12BZK are shown to have a narrow therapeutic index recommending caution in their use in contraceptive formulations. CONCLUSIONS

  2. Differential toxicity of Disperse Red 1 and Disperse Red 13 in the Ames test, HepG2 cytotoxicity assay, and Daphnia acute toxicity test.

    Science.gov (United States)

    Ferraz, E R A; Umbuzeiro, G A; de-Almeida, G; Caloto-Oliveira, A; Chequer, F M D; Zanoni, M V B; Dorta, D J; Oliveira, D P

    2011-10-01

    Azo dyes are of environmental concern due to their degradation products, widespread use, and low-removal rate during conventional treatment. Their toxic properties are related to the nature and position of the substituents with respect to the aromatic rings and amino nitrogen atom. The dyes Disperse Red 1 and Disperse Red 13 were tested for Salmonella mutagenicity, cell viability by annexin V, and propidium iodide in HepG2 and by aquatic toxicity assays using daphnids. Both dyes tested positive in the Salmonella assay, and the suggestion was made that these compounds induce mainly frame-shift mutations and that the enzymes nitroreductase and O-acetyltransferase play an important role in the observed effect. In addition, it was shown that the presence of the chlorine substituent in Disperse Red 13 decreased the mutagenicity about 14 times when compared with Disperse Red 1, which shows the same structure as Disperse Red 13, but without the chlorine substituent. The presence of this substituent did not cause cytotoxicity in HepG2 cells, but toxicity to the water flea Daphnia similis increased in the presence of the chlorine substituent. These data suggest that the insertion of a chlorine substituent could be an alternative in the design of dyes with low-mutagenic potency, although the ecotoxicity should be carefully evaluated. Copyright © 2010 Wiley Periodicals, Inc.

  3. Enhanced effect of geldanamycin nanocomposite against breast cancer cells growing in vitro and as xenograft with vanquished normal cell toxicity.

    Science.gov (United States)

    Prabhu, Suma; Ananthanarayanan, Preeta; Aziz, Sajida Kannangar; Rai, Sharada; Mutalik, Srinivas; Sadashiva, Satish Rao Bola

    2017-04-01

    Despite enormous advances in remedies developed for breast cancer, an effective therapeutic strategy by targeting malignant cells with the least normal tissue toxicity is yet to be developed. Hsp90 is considered to be an important therapeutic target to inhibit cell proliferation. Geldanamycin (GDM), a potent inhibitor of Hsp90 was withdrawn from clinical trials due to its undesirable hepatotoxicity. We report a superparamagnetic iron oxide (SPION) based polymeric nanocomposite of GDM augmenting anticancer competence with decreased hepatic toxicity. The particle size of nanocomposite was ascertained to be 76±10nm with acceptable stability. A comparative dose dependent in vitro validation of cytotoxicity showed an enhanced cellular damage and necrosis in breast cancer (MCF-7) cell line at a low dose of 5.49nM (in GDM nanocomposite) in contrast to 20nM of pure GDM, while normal breast epithelial cells (MCF-10A) were least affected. Besides, in vivo study (in breast cancer xenografts) substantiated 2.7 fold delay in tumor progression mediated by redundancy in the downstream functions of p-Akt and MAPK-Erk leading to apoptosis with negligible hepatotoxicity. Pure GDM disrupted the function and morphology of liver with lesser therapeutic efficacy than the GDM nanocomposite. These findings deduce that GDM based polymeric magnetite nanocomposite play a vital role in efficacious therapy while vanquishing normal cells and hepatic toxicity and thereby promising it to be reinstated in clinics. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Acute toxicity profiling of the ethyl acetate fraction of Swietenia macrophylla seeds and in-vitro neuroprotectio

    Directory of Open Access Journals (Sweden)

    Mustak Sayyad

    2017-02-01

    Full Text Available Swietenia macrophylla (SM is a medicinally important plant found in tropical and subtropical regions of the world. The ethyl acetate fraction of the seeds of S. macrophylla (SMEAF is reported to exhibit potent anticancer, antitumor, anti-inflammatory and antifeedant activities. Till date, there have been no studies reported on the acute oral toxicity profile of the ethyl acetate fraction of the seeds of SM. The objective of the present study was to determine the acute toxicity of SMEAF and evaluate the in-vitro neuroprotective activity of SMEAF using primary neuronal cell cultures. In acute oral toxicity study, the SMEAF did not produce any lethal signs of morbidity and mortality. Histo-pathological findings, support the safety of SMEAF, as there were no significant changes observed in any of the parameters studied. Based on the results obtained in MTT assay, we infer that SMEAF has a significant neuroprotective effect, as it increased the cell viability and exhibited protection to the neuronal cells against TBHP induced oxidative stress. Thus, SMEAF can be suggested for use in the development of herbal drug formulations with neuroprotective potential.

  5. Influences of the coating on silver nanoparticle toxicity in a chronic test with Daphnia magna

    DEFF Research Database (Denmark)

    Sakka, Y.; Mackevica, Aiga; Skjolding, Lars Michael

    2015-01-01

    Sources for differences in silver nanoparticle toxicity at standardized conditions can be numerous. They range from particle properties and their actual concentrations to differences in uptake or depuration by the test organisms. In the present study we compared the toxicity of two differently...... coated AgNP in a chronic Daphnia test. One type of AgNP was coated with citrate (cAgNP), the other AgNP were generally uncoated (pAgNP; p= pure), but sterically stabilized by an organic dispersant. Particles with a similar shape and diameter were chosen. The focus of the study was to relate observed...

  6. In Vitro Protective Potentials of Annona muricata Leaf Extracts Against Sodium Arsenite-induced Toxicity.

    Science.gov (United States)

    George, Vazhappilly Cijo; Kumar, Devanga Ragupathi Naveen; Suresh, Palamadai Krishnan; Kumar, Rangasamy Ashok

    2015-01-01

    Sodium arsenite (NaAsO2) is a metalloid which is present widely in the environment and its chronic exposure can contribute to the induction of oxidative stress, resulting in disturbances in various metabolic functions including liver cell death. Hence, there is a need to develop drugs from natural sources, which can reduce arsenic toxicity. While there have been reports regarding the antioxidant and protective potentials of Annona muricataleaf extracts, our study is the first ofits kind to extend these findings by specifically evaluating its ability to render protection against sodium arsenite (NaAsO2) induced toxicity (10 μM) in WRL-68 (human hepatic cells) and human erythrocytes by employing XTT and haemolysis inhibition assays respectively. The methanolic extract exhibited higher activity than the aqueous extract in both assays. The results showed a dose-dependent decrease in arsenic toxicity in both WRL-68 cells and erythrocytes, suggesting the protective nature of Annona muricatato mitigate arsenic toxicity. Hence the bioactive extracts can further be scrutinized for the identification and characterization of their principal contributors.

  7. In Vitro and In Vivo Toxicity of Garcinia or Hydroxycitric Acid: A Review

    Directory of Open Access Journals (Sweden)

    Li Oon Chuah

    2012-01-01

    Full Text Available Obesity is one of the pandemic chronic diseases commonly associated with health disorders such as heart attack, high blood pressure, diabetes or even cancer. Among the current natural products for obesity and weight control, Garcinia or more specifically hydroxycitric acid (HCA extracted from Garcinia has been widely used. The evaluation of the potential toxicity of weight control supplement is of the utmost importance as it requires long term continuous consumption in order to maintain its effects. Majority of reports demonstrated the efficacy of Garcinia/HCA without any toxicity found. However, a few clinical toxicity reports on weight-loss diet supplements of which some were combinations that included Garcinia/HCA as an active ingredient showed potential toxicity towards spermatogenesis. Nonetheless, it cannot be concluded that Garcinia/HCA is unsafe. Those products which have been reported to possess adverse effects are either polyherbal or multi-component in nature. To date, there is no case study or report showing the direct adverse effect of HCA. The structure, mechanism of action, long history of the use of Garcinia/HCA and comprehensive scientific evidence had shown “no observed adverse effect level (NOAEL” at levels up to 2800 mg/day, suggesting its safety for use.

  8. In Vitro Tests for Aerosol Deposition. V: Using Realistic Testing to Estimate Variations in Aerosol Properties at the Trachea.

    Science.gov (United States)

    Wei, Xiangyin; Hindle, Michael; Delvadia, Renishkumar R; Byron, Peter R

    2017-10-01

    The dose and aerodynamic particle size distribution (APSD) of drug aerosols' exiting models of the mouth and throat (MT) during a realistic inhalation profile (IP) may be estimated in vitro and designated Total Lung Dose, TLDin vitro, and APSDTLDin vitro, respectively. These aerosol characteristics likely define the drug's regional distribution in the lung. A general method was evaluated to enable the simultaneous determination of TLDin vitro and APSDTLDin vitro for budesonide aerosols' exiting small, medium and large VCU-MT models. Following calibration of the modified next generation pharmaceutical impactor (NGI) at 140 L/min, variations in aerosol dose and size exiting MT were determined from Budelin® Novolizer® across the IPs reported by Newman et al., who assessed drug deposition from this inhaler by scintigraphy. Values for TLDin vitro from the test inhaler determined by the general method were found to be statistically comparable to those using a filter capture method. Using new stage cutoffs determined by calibration of the modified NGI at 140 L/min, APSDTLDin vitro profiles and mass median aerodynamic diameters at the MT exit (MMADTLDin vitro) were determined as functions of MT geometric size across Newman's IPs. The range of mean values (n ≥ 5) for TLDin vitro and MMADTLDin vitro for this inhaler extended from 6.2 to 103.0 μg (3.1%-51.5% of label claim) and from 1.7 to 3.6 μm, respectively. The method enables reliable determination of TLDin vitro and APSDTLDin vitro for aerosols likely to enter the trachea of test subjects in the clinic. By simulating realistic IPs and testing in different MT models, the effects of major variables on TLDin vitro and APSDTLDin vitro may be studied using the general method described in this study.

  9. Review of the use of Ceramium tenuicorne growth inhibition test for testing toxicity of substances, effluents, products sediment and soil

    Science.gov (United States)

    Eklund, Britta

    2017-08-01

    A growth inhibition test has been developed based on two clones of the red macroalga Ceramium tenuicorne, one originating from 7 PSU and the other from 20 PSU. The species can be adapted to different salinities and the test can be carried out between 4 and 32 PSU. This test became an ISO standard in 2010 (ISO 107 10) for testing of chemicals and water effluents. In this study new and published data has been compiled on toxicity of single substances, waste waters from pulp mills, leachates from antifouling paints, harbour sediments and soil used for maintenance of leisure boats. The results show that the alga is sensitive to both metals and organic compounds and to biocides used in antifouling paints. By testing leachates from antifouling paints these could be ranked according to their toxicity. Similarly, the toxicity of waste waters from pulp mills was determined and the efficiency of secondary treatment evaluated. Further, the test method proved useful to test the toxicity in sediment samples. Sediments from small town harbours and ship lanes were shown to be harmful and compounds originating from antifouling paints were responsible for a large part of the inhibiting effect. The alga proved to be sensitive to contaminants leaking from boat yard soil. The growth inhibition test is a robust test that has high repeatability and reproducibility and easily can be applied on water, soil and sediment samples without being too costly. The species is found worl-wide in temperate waters, which makes the results relevant for large areas. In the Baltic Sea C. tenuicorne is the most common red alga species and is thus particularly relevant for this area. The overall results show that contaminants from boat activities and the use of antifouling paints in particular pose a threat to the environment.

  10. Acute toxicity tests and meta-analysis identify gaps in tropical ecotoxicology for amphibians.

    Science.gov (United States)

    Ghose, Sonia L; Donnelly, Maureen A; Kerby, Jacob; Whitfield, Steven M

    2014-09-01

    Amphibian populations are declining worldwide, particularly in tropical regions where amphibian diversity is highest. Pollutants, including agricultural pesticides, have been identified as a potential contributor to decline, yet toxicological studies of tropical amphibians are very rare. The present study assesses toxic effects on amphibians of 10 commonly used commercial pesticides in tropical agriculture using 2 approaches. First, the authors conducted 8-d toxicity assays with formulations of each pesticide using individually reared red-eyed tree frog (Agalychnis callidryas) tadpoles. Second, they conducted a review of available data for the lethal concentration to kill 50% of test animals from the US Environmental Protection Agency's ECOTOX database to allow comparison with their findings. Lethal concentration estimates from the assays ranged over several orders of magnitude. The nematicides terbufos and ethoprophos and the fungicide chlorothalonil were very highly toxic, with evident effects within an order of magnitude of environmental concentrations. Acute toxicity assays and meta-analysis show that nematicides and fungicides are generally more toxic than herbicides yet receive far less research attention than less toxic herbicides. Given that the tropics have a high diversity of amphibians, the findings emphasize the need for research into the effects of commonly used pesticides in tropical countries and should help guide future ecotoxicological research in tropical regions. © 2014 SETAC.

  11. Comparative In Vitro Toxicity Evaluation of Heavy Metals (Lead, Cadmium, Arsenic, and Methylmercury) on HT-22 Hippocampal Cell Line.

    Science.gov (United States)

    Karri, Venkatanaidu; Kumar, Vikas; Ramos, David; Oliveira, Eliandre; Schuhmacher, Marta

    2017-10-09

    Heavy metals are considered some of the most toxic environmental pollutants. Exposure to heavy metals including lead (Pb), cadmium (Cd), arsenic (As), and methyl mercury (MeHg) has long been known to cause damage to human health. Many recent studies have supported the hippocampus as the major target for these four metals for inflicting cognitive dysfunction. In the present study, we proposed hippocampal relevant in vitro toxicity of Pb, Cd, As, and MeHg in HT-22 cell line. This study reports, initially, cytotoxic effects in acute, subchronic, chronic exposures. We further investigated the mechanistic potency of DNA damage and apoptosis damage with the observed cytotoxicity. The genotoxicity and apoptosis were measured by using the comet assay, annexin-V FTIC / propidium iodide (PI) assay, respectively. The results of cytotoxicity assay clearly demonstrated significant concentration and time-dependent effects on HT-22 cell line. The genotoxic and apoptosis effects also concentration-dependent fashion with respect to their potency in the range of IC10-IC30, maximal level of damage observed in MeHg. In conclusion, the obtained result suggests concentration and potency-dependent response; the maximal level of toxicity was observed in MeHg. These novel findings support that Pb, Cd, As, and MeHg induce cytotoxic, genotoxic, and apoptotic effects on HT-22 cells in potency-dependent manner; MeHg> As> Cd> Pb. Therefore, the toxicity of Pb, Cd, As, and MeHg could be useful for knowing the common underlying molecular mechanism, and also for estimating the mixture impacts on HT-22 cell line.

  12. In vitro antibacterial activity and acute toxicity studies of aqueous-methanol extract of Sida rhombifolia Linn. (Malvaceae).

    Science.gov (United States)

    Assam, Assam J P; Dzoyem, J P; Pieme, C A; Penlap, V B

    2010-07-27

    Many bacteria among the Enterobacteria family are involved in infectious diseases and diarrhoea. Most of these bacteria become resistant to the most commonly used synthetic drugs in Cameroon. Natural substances seem to be an alternative to this problem. Thus the aim of this research was to investigate the in vitro antibacterial activity of the methanol and aqueous-methanol extracts of Sida rhombifolia Linn (Malvaceae) against seven pathogenic bacteria involved in diarrhoea. Acute toxicity of the most active extract was determined and major bioactive components were screened. The agar disc diffusion and the agar dilution method were used for the determination of inhibition diameters and the Minimum Inhibitory Concentration (MICs) respectively. The acute toxicity study was performed according WHO protocol. The aqueous-methanol extract (1v:4v) was the most active with diameters of inhibition zones ranging from 8.7 - 23.6 mm, however at 200 microg/dic this activity was relatively weak compared to gentamycin. The MICs of the aqueous-methanol extract (1v:4v) varied from 49.40 to 78.30 microg/ml. Salmonella dysenteriae was the most sensitive (49.40 microg/ml). For the acute toxicity study, no deaths of rats were recorded. However, significant increase of some biochemical parameters such as aspartate amino-transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and creatinine (CRT) were found. The phytochemical analysis of the aqueous methanol extract indicated the presence of tannins, polyphenols, alkaloids, glycosides, flavonoids and saponins The results showed that the aqueous-methanol extract of S. rhombifolia exhibited moderate antibacterial activity. Some toxic effects were found when rats received more than 8 g/kg bw of extract.

  13. Development of methods for laboratory culture and toxicity testing of the endangered desert pupfish, Cyprinodon macularius, and evaluation of the acute toxicity of selenium

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We conducted a series of studies to evaluate methods for laboratory culture and toxicity testing with the endangered desert pupfish, Cyprinodon macularius. This...

  14. Evaluation of different biological test systems to assess the toxicity of metabolites from fungal biocontrol agents.

    Science.gov (United States)

    Skrobek, Anke; Boss, Désirée; Défago, Geneviève; Butt, Tariq M; Maurhofer, Monika

    2006-02-08

    The development of fungal biocontrol agents (BCAs) as alternatives to chemical pesticides is of increasing public interest. Tools to assess the toxicity of the secondary metabolites that these BCAs produce are often not available or existing methods have not yet been evaluated for these compounds. This study compares five different test systems, which include a representative bacterium, protozoan, arthropod and insect and human cell lines, as regards their sensitivity. It also compares the cost in time and resources for conducting the tests. Pure metabolites and crude extracts from two fungal BCAs as well as two chemical pesticides (hoestar and chlorpyrifos) and the mycotoxin patulin were employed as test compounds. All tests systems proved to be suitable for toxicity studies of metabolites from fungal BCAs and showed different grades of sensitivity to the different substances. The possibility of employing an array of test systems to determine ecotoxicological properties is discussed.

  15. Risk assessment of paracetamol-induced liver toxicity based on human in vitro data.

    NARCIS (Netherlands)

    Groothuis, Geny; Mafirakureva, Nyashadzaishe; Proost, Johannes; Jetten, M; Kleinjans, Jos; Lommen, A; Peijnenburg, A; Vredenburg, G; Vermeulen, N; Russel, Frans G. M.

    Currently risk assessment is based on animal experiments with limited success. The aim of this study was to explore the feasibility to replace the use of animals in risk assessment for drug-induced liver injury, by hazard identification and kinetic modeling based on human in vitro data for

  16. Genotoxicity of silver nanoparticles evaluated using the Ames test and in vitro micronucleus assay.

    Science.gov (United States)

    Li, Yan; Chen, David H; Yan, Jian; Chen, Ying; Mittelstaedt, Roberta A; Zhang, Yongbin; Biris, Alexandru S; Heflich, Robert H; Chen, Tao

    2012-06-14

    Silver nanoparticles (AgNPs) have antimicrobial properties, which have contributed to their widespread use in consumer products. A current issue regarding nanomaterials is the extent to which existing genotoxicity assays are useful for evaluating the risks associated with their use. In this study, the genotoxicity of 5 nm AgNPs was assessed using two standard genotoxicity assays, the Salmonella reverse mutation assay (Ames test) and the in vitro micronucleus assay. Using the preincubation version of the Ames assay, Salmonella strains TA102, TA100, TA1537, TA98, and TA1535 were treated with 0.15-76.8 μg/plate of the AgNPs. Toxicity limited the doses that could be assayed to 2.4-38.4 μg/plate; no increases in mutant frequency over the vehicle control were found for the concentrations that could be assayed. Human lymphoblastoid TK6 cells were treated with 10-30 μg/ml AgNPs, and additional cells were treated with water and 0.73 gy X-rays as vehicle and positive controls. Micronucleus frequency was increased by the AgNP treatment in a dose-dependent manner. At a concentration of 30 μg/ml (with 45.4% relative population doubling), AgNPs induced a significant, 3.17-fold increase with a net increase of 1.60% in micronucleus frequency over the vehicle control, a weak positive response by our criteria. These results demonstrate that the 5 nm AgNP are genotoxic in TK6 cells. Also, the data suggest that the in vitro micronucleus assay may be more appropriate than the Ames test for evaluating the genotoxicity of the AgNPs. Published by Elsevier B.V.

  17. In vitro toxicity of functionalised nanoclays is mainly driven by the presence of organic modifiers.

    Science.gov (United States)

    Janer, Gemma; Fernández-Rosas, Elisabet; Mas del Molino, Ezequiel; González-Gálvez, David; Vilar, Gemma; López-Iglesias, Carmen; Ermini, Valentina; Vázquez-Campos, Socorro

    2014-05-01

    Little information exists on the toxicological hazards associated to organo-modified clays. We evaluated the cytotoxicity of a series of pristine and organo-modified nanoclays in different cell lines. The calculated IC50 values for cell viability ranged from 1.4 to 47 µg/mL for the six organoclays used and were above 100 µg/mL for the pristine nanoclays. The IC50 values of the organoclays were driven by the proportion and structure of the quaternary ammonium compound used as surface organic modifier. No differences in cell toxicity were observed between the large and small-sized (additional milling step) nanoclay batches, although their size differences related mostly to upper range of the size distribution. Despite their lower toxicity, pristine nanoclays induced apoptosis and were found in cytoplasmic vesicles of exposed cells. Organoclays were also found in cytoplasmic vesicles, although the size of the agglomerates was larger and the efficiency of uptake was considerably lower.

  18. Structure Elucidation and in Vitro Toxicity of New Azaspiracids Isolated from the Marine Dinoflagellate Azadinium poporum

    Directory of Open Access Journals (Sweden)

    Bernd Krock

    2015-10-01

    Full Text Available Two strains of Azadinium poporum, one from the Korean West coast and the other from the North Sea, were mass cultured for isolation of new azaspiracids. Approximately 0.9 mg of pure AZA-36 (1 and 1.3 mg of pure AZA-37 (2 were isolated from the Korean (870 L and North Sea (120 L strains, respectively. The structures were determined to be 3-hydroxy-8-methyl-39-demethyl-azaspiracid-1 (1 and 3-hydroxy-7,8-dihydro-39-demethyl-azaspiracid-1 (2 by 1H- and 13C-NMR. Using the Jurkat T lymphocyte cell toxicity assay, (1 and (2 were found to be 6- and 3-fold less toxic than AZA-1, respectively.

  19. Development of a standard acute dietary toxicity test for the silkworm (Bombyx mori L.)

    NARCIS (Netherlands)

    Sun, X.; Valk, H.; Jiang, H.; Wang, X.; Yuan, S.; Zhang, Y.; Roessink, I.; Gao, X.

    2012-01-01

    Larvae of the silkworm (Bombyx mod L.) may be exposed to pesticide residues on the leaves of their food plant, the mulberry tree (Morus spp.), which can lead to adverse effects on silk production. A new acute dietary toxicity test method was evaluated as the basis for pesticide risk assessment. A

  20. Animal alternatives for whole effluent toxicity testing: Perspectives from a global workshop (presentation)

    Science.gov (United States)

    Since the 1940s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that toxicit...

  1. Animal alternatives for whole effluent toxicity testing: Perspectives from a global workshop

    Science.gov (United States)

    Since the 1940’s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that ...

  2. In vitro assessment of human airway toxicity from major aldehydes in automotive emissions

    Energy Technology Data Exchange (ETDEWEB)

    Grafstroem, R.C. [Karolinska Inst., Stockholm (Sweden). Inst. of Environmental Medicine

    1997-09-01

    Automotive exhausts can significantly contribute to the levels of reactive aldehydes, including formaldehyde, acetaldehyde and acrolein, in urban air. The use of alcohols as an alternative fuel for gasoline or diesel may further increase these emissions. Since it is unclear if aldehyde inhalation may induce pathological states, including cancer, in human airways, the toxic properties of the above-mentioned aldehydes were studied in cultured target cell types. Each aldehyde modified vital cellular functions in a dose-dependent manner, and invariably inhibited growth and induced abnormal terminal differentiation. Decreases of cellular thiols and increases of intracellular Ca{sup 2+} were observed, and moreover, variable types and amounts of short-lived or persistent genetic damage were induced. The concentrations required for specified levels of a particular type of injury varied up to 10000-fold among the aldehydes. Overall, distinctive patterns of cytopathological activity were observed, which differed both qualitatively and quantitatively among the aldehydes. Finally, aldehydes inhibited DNA repair processes and increased cytotoxicity and mutagenesis in synergy with other known toxicants, indicating that aldehydes may also enhance damage by other constituents in automotive exhausts. In summary, the aldehydes, notably {sup m}u{sup M}-mM formaldehyde, caused pathological effects and induced mechanisms that relate to acute toxicity and cancer development in airway epithelial cells. Since `no-effect` levels may not exist for carcinogenic agents, the overall results support a need for elimination of aldehydes in automotive exhausts. 41 refs

  3. In vitro toxicity of the galanin receptor 3 antagonist SNAP 37889.

    Science.gov (United States)

    Koller, Andreas; Rid, Raphaela; Beyreis, Marlena; Bianchini, Rodolfo; Holub, Barbara S; Lang, Andreas; Locker, Felix; Brodowicz, Bernhard; Velickovic, Ognjen; Jakab, Martin; Kerschbaum, Hubert; Önder, Kamil; Kofler, Barbara

    2016-04-01

    Galanin and its receptors (GAL1, GAL2, GAL3) modulate a range of neuronal, immune and vascular activities. In vivo administration of SNAP 37889 (1-phenyl-3-[[3-(trifluoromethyl)phenyl]imino]-1H-indol-2-one), a potent small non-peptidergic antagonist of GAL3, was reported to reduce anxiety- and depression-related behavior, ethanol consumption, and antagonizes the effect of galanin on plasma extravasation in rodent models. Accordingly, SNAP 37889 has been proposed as a potential therapeutic agent to treat anxiety and depression disorders. Therefore, we evaluated the toxicity of SNAP 37889 to different cell types. Our experiments revealed that SNAP 37889 (≥10μM) induced apoptosis in epithelial (HMCB) and microglial (BV-2) cell lines expressing endogenous GAL3, in peripheral blood mononuclear cells and promyelocytic leukemia cells (HL-60) expressing GAL2, and in a neuronal cell line (SH-SY5Y) lacking galanin receptor expression altogether. In conclusion, SNAP 37889 is toxic to a variety of cell types independent of GAL3 expression. We caution that the clinical use of SNAP 37889 at doses that might be used to treat anxiety- or depression- related diseases could have unexpected non-galanin receptor-mediated toxicity, especially on immune cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Comparative cardiac toxicity of anthracyclines in vitro and in vivo in the mouse.

    Directory of Open Access Journals (Sweden)

    Stefano Toldo

    Full Text Available PURPOSE: The antineoplastic efficacy of anthracyclines is limited by their cardiac toxicity. In this study, we evaluated the toxicity of doxorubicin, non-pegylated liposomal-delivered doxorubicin, and epirubicin in HL-1 adult cardiomyocytes in culture as well as in the mouse in vivo. METHODS: The cardiomyocytes were incubated with the three anthracyclines (1 µM to assess reactive oxygen generation, DNA damage and apoptotic cell death. CF-1 mice (10/group received doxorubicin, epirubicin or non-pegylated liposomal-doxorubicin (10 mg/kg and cardiac function was monitored by Doppler echocardiography to measure left ventricular ejection fraction (LVEF, heart rate (HR and cardiac output (CO both prior to and 10 days after drug treatment. RESULTS: In HL-1 cells, non-pegylated liposomal-doxorubicin generated significantly less reactive oxygen species (ROS, as well as less DNA damage and apoptosis activation when compared with doxorubicin and epirubicin. Cultured breast tumor cells showed similar sensitivity to the three anthracyclines. In the healthy mouse, non-pegylated liposomal doxorubicin showed a minimal and non-significant decrease in LVEF with no change in HR or CO, compared to doxorubicin and epirubicin. CONCLUSION: This study provides evidence for reduced cardiac toxicity of non-pegylated-liposomal doxorubicin characterized by attenuation of ROS generation, DNA damage and apoptosis in comparison to epirubicin and doxorubicin.

  5. In vitro testing of dual-mode thulium microsurgical laser

    Science.gov (United States)

    Keller, Matthew D.; Stafford, James A.; Schmidt, Brandon P.; Wells, Jonathon D.

    2012-02-01

    Recently, thulium (Tm) fiber lasers have been investigated for use in surgical procedures, especially in urology, because of their numerous advantages over existing laser systems. Lockheed Martin Aculight has recently developed the first truly dual-mode Tm laser, which can be operated in either CW or in short-pulsed mode to produce high peak power. The goal of this study was to assess both the soft tissue ablation performance of this laser in vitro and the feasibility of using it for lithotripsy. Ablation tests were performed on liver tissue, chicken breast, and porcine skin, using a 100μm or 200μm delivery fiber, and operated in CW mode or pulsed (~350ns pulse widths) at 10kHz or 1kHz. Ablation efficiencies for long (3 minutes) exposures and collateral damage zones for short (3-5 seconds) exposures were determined for the different pulse modes and a range of pulse energies. In all tissues, the most energy-efficient ablation occurred for the 10kHz pulsed mode operating just above ablation threshold, while the highest mass removal rate occurred in 10kHz pulsed mode operating at max energy (2.1 mJ). In histological sections from short exposures, 10kHz pulsed exposures created slightly smaller thermal coagulation zones than energy-matched CW exposures, while 1kHz deliveries had substantially smaller thermal damage zones. In addition, using a 100μm fiber, the 10kHz mode was able to fragment samples of uric acid stones.

  6. 76 FR 38169 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2011-06-29

    ..., Chemical Control Division (7405M), Office of Pollution Prevention and Toxics, Environmental Protection... interest to those persons who are concerned about data on health and/or environmental effects and other.... metallocenes, paints and varnishes, flame retardant for plastics. Methyl isoamyl ketone Percutaneous Absorption...

  7. Determination of genetic toxicity and potential carcinogenicity in vitro--challenges post the Seventh Amendment to the European Cosmetics Directive.

    Science.gov (United States)

    Tweats, D J; Scott, A D; Westmoreland, C; Carmichael, P L

    2007-01-01

    Genetic toxicology and its role in the detection of carcinogens is currently undergoing a period of reappraisal. There is an increasing interest in developing alternatives to animal testing and the three R's of reduction, refinement and replacement are the basis for EU and national animal protection laws the Seventh Amendment to the EU Cosmetics Directive will ban the marketing of cosmetic/personal care products that contain ingredients that have been tested in animal models. Thus in vivo tests such as the bone marrow micronucleus test, which has a key role in current testing strategies for genotoxicity, will not be available for this class of products. The attrition rate for new, valuable and safe chemicals tested in an in vitro-only testing battery, using the in vitro tests currently established for genotoxicity screening, will greatly increase once this legislation is in place. In addition there has been an explosion of knowledge concerning the cellular and molecular events leading to carcinogenesis. This knowledge has not yet been fully factored into screening chemicals for properties that are not directly linked to mutation induction. Thus there is a pressing need for new, more accurate approaches to determine genotoxicity and carcinogenicity. However, a considerable challenge is presented for these new approaches to be universally accepted and new tests sufficiently validated by March 2009 when the animal testing and marketing bans associated with the Seventh Amendment are due to come into force. This commentary brings together ideas and approaches from several international workshops and meetings to consider these issues.

  8. Sulfhydryl-Modified Fe3O4@SiO2 Core/Shell Nanocomposite: Synthesis and Toxicity Assessment in Vitro.

    Science.gov (United States)

    Guo, Xueyi; Mao, Fangfang; Wang, Weijia; Yang, Ying; Bai, Zhiming

    2015-07-15

    The objectives of this study are to prepare sulfhydryl-modified Fe3O4@SiO2 core/shell magnetic nanocomposites, assess their toxicity in vitro, and explore their potential application in the biomedical fields. Fe3O4 nanoparticles synthesized by facile solvothermal method were coated with SiO2 via the Stöber method and further modified by the meso-2,3-dimercaptosuccinic acid (DMSA) to prepare Fe3O4@SiO2@DMSA nanoparticles. The morphology, structure, functional groups, surface charge, and magnetic susceptibility of the nanoparticles were characterized by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, zeta potential analysis, dynamic laser scattering, and vibrating sample magnetometer. Cytotoxicity tests and hemolysis assay were also carried out. Experimental results show that the toxicity of sulfhydryl-modified Fe3O4@SiO2 core/shell nanoparticles in mouse fibroblast (L-929) cell lines is between grade 0 and grade 1, and the material lacks hemolytic activity, indicating good biocompatibility of this Fe3O4@SiO2@DMSA nanocomposite, which is suitable for further application in biochemical fields.

  9. Characterization of 3D embryonic C57BL/6 and A/J mouse midbrain micromass in vitro culture systems for developmental neurotoxicity testing.

    Science.gov (United States)

    Park, Julie Juyoung; Weldon, Brittany A; Hong, Sungwoo; Workman, Tomomi; Griffith, William C; Park, Julie H; Faustman, Elaine M

    2017-12-18

    In vitro micromass culture systems have been proposed as an alternative method for developmental toxicity assessment to reduce the need for resource-intensive in vivo toxicity testing. In this study, a three-dimensional in vitro embryonic mouse midbrain culture system is characterized in two mouse strains to facilitate gene x environment considerations. Gestational day (GD) 11 C57BL/6 or GD 12 A/J mouse midbrain cells were isolated and cultured in high-density micromass format for 22days in vitro (DIV). Hematoxylin intensity and protein content revealed that neuronal differentiation increases linearly over time in both C57BL/6 and A/J cultures. Protein expression showed time-dependent proliferation markers (PCNA) increased significantly between DIV 4-6 compared to DIV 1. Early and late differentiation markers (e.g. β-tubulin III and NMDAɛ1) were expressed between DIV 6-8 and DIV 8-15, respectively. Immunohistochemistry and protein expression results for proliferation and differentiation markers were concordant. Protein expression patterns for the two mouse strain micromass systems were similar. This study characterizes a novel method for investigating early neurogenesis and may be used to characterize neurodevelopmental toxicity in vitro. Our findings show how the use of different mouse strains in neurodevelopmental studies may extend test systems for gene and environment interaction studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. The use of KnockOut serum replacement (KSR) in three dimensional rat testicular cells co-culture model: An improved male reproductive toxicity testing system.

    Science.gov (United States)

    Zhang, Xiaofang; Wang, Lei; Zhang, Xiaodong; Ren, Lijun; Shi, Wenjing; Tian, Yijun; Zhu, Jiangbo; Zhang, Tianbao

    2017-08-01

    Recent increasing restrictions on animals have persuaded researchers to seek in vitro alternatives that could reduce the use of experimental animals and provide a unique methodology for the exploration of specific toxicant mechanisms in testes. Although various in vitro models have been reported, their application in toxicological studies has been limited due to various reasons. In the present study, an improved three-dimensional rat testicular cell co-culture model was established by the addition of KSR to the culture medium instead of FBS.The effects of KSR and FBS were assessed and followed by an assessment of the effects of BPA on somatic cell function and germ cell differentiation in vitro using this improved co-culture model. It was found that the addition of KSR could enhance cell proliferation and germ cell meiosis, which confirmed the functional integrity of the co-culture model. Finally, the effects of BPA on the in vitro model demonstrated that the model could successfully mimic in vivo testis physiology phenomenon. We concluded that the modified model could be used to evaluate various chemicals on rat testis cells and investigate the specific mechanisms of toxicant activity in the testis in future studies. Copyright © 2017. Published by Elsevier Ltd.

  11. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC{sub 50} values of other test models

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S., E-mail: bkhangarot@hotmail.com [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India); Das, Sangita [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2009-12-30

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC{sub 50}) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC{sub 50} values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r{sup 2}) for 17 physicochemical properties of metals or metal ions and EC{sub 50}s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK{sub sp}), softness parameter and some other physicochemical characteristics were significantly correlated with EC{sub 50}s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC{sub 50}s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  12. A roadmap for the development of alternative (non-animal) methods for systemic toxicity testing

    OpenAIRE

    Ruhdel, Irmela; Vanparys, Philippe; Knudsen, Thomas B.; ROGGEN Erwin; Oué draogo, Gladys; Basketter, David A; Daneshian, Mardas; Eskes, Chantra; Rossi, Annamaria; Skinner, Nigel; Blaauboer, Bas; Pelkonen, Olavi; Maxwell, Gavin; Yager, James

    2012-01-01

    Systemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new products (such as nanoparticles or cell therapies), the limited predictivity of traditional tests for human health effects, duration and costs of current approaches, and animal welfare considerations. The latter holds esp...

  13. Dredged Material Evaluations: Review of Zooplankton Toxicity Test Methods for Marine Water Quality Evaluations

    Science.gov (United States)

    2016-09-01

    for elutriate toxicity tests are fish, invertebrates ( crustaceans ), and zooplankton. Freshwater evaluations (following CWA regulations) use standard...one species each representative of phytoplankton or zooplankton, crustacean or mollusk, and fish species chosen from ERDC TN-DOER-R24 September...Organisation for Economic Cooperation and Development (OECD) and ASTM. Much of this work has focused on full life-cycle testing of the epibenthic

  14. Toxicity of uranium, molybdenum, nickel, and arsenic to Hyalella azteca and Chironomus dilutus in water-only and spiked-sediment toxicity tests.

    Science.gov (United States)

    Liber, Karsten; Doig, Lorne E; White-Sobey, Suzanne L

    2011-07-01

    A series of laboratory spiked-sediment toxicity tests with the amphipod Hyalella azteca and the midge Chironomus dilutus were undertaken to determine acute and chronic toxicity thresholds for uranium (U), molybdenum (Mo), nickel (Ni), and arsenic (As) based on both whole-sediment (total) and pore water exposure concentrations. Water-only toxicity data were also generated from separate experiments to determine the toxicities of these metals/metalloids under our test conditions and to help evaluate the hypothesis that pore water metal concentrations are better correlated with sediment toxicity to benthic organisms than whole-sediment metal concentrations. The relative toxicity of the four elements tested differed depending on which test species was used and whether whole-sediment or pore water metal concentrations were correlated with effects. Based on measured whole-sediment concentrations, Ni and As were the two most acutely toxic elements to H. azteca with 10-d LC50s of 521 and 532 mg/kg d.w., respectively. Measured pore water concentrations indicated that U and Ni were the two most acutely toxic elements, with 10-d LC50s to H. azteca of 2.15 and 2.05 mg/L, respectively. Based on pore water metal concentrations, the no-observed-effect concentrations (NOECs) for growth were (H. azteca and C. dilutus, respectively) 0.67 and 0.21 mg/L for U, 260-fold higher, respectively, than the CNSC LELs for these metals/metalloids. Data on pore water metal concentrations in toxic sediment would be a useful addition to future Guidelines documents. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Toxicity testing with constant or decreasing concentrations of chemically dispersed oil

    Energy Technology Data Exchange (ETDEWEB)

    Kiesser, S.L.; Fleishmann, M.L.; McQuerry, D.L.; Riley, R.G.

    1982-10-01

    An exposure system and method of quantitating toxicity have been developed to provide an estimate of the effects of dispersed oil on marine organisms under a variety of exposure conditions. Results of constant concentration exposures (for hours or days) can be compared to those of diluting exposures (decreasing to zero in 8 or 24 h) on a basis of the ''toxicity index.'' This index is equal to the total exposure when time in hours or days is multiplied by the concentration at each hour (ppm h or ppm days). Tests have been conducted with shrimp (Pandalus danae), two oils (Prudhoe Bay crude and a light Arabian crude), and two dispersants. There is a seasonal pattern to the tolerance of the shrimp. Tests in the colder months (fall/winter) produce toxicity indices approximately three times higher than summer/spring values. During tests in summer, there was also little difference observed when the toxicity of the light Arabian oil was compared to that of Prudhoe Bay crude (2.3 and 3.4 ppm days, respectively). The usefulness of our methods is that in addition to the comparisons already noted, it is possible to predict the outcome of dispersant application under varying environmental conditions.

  16. Implementation challenges for designing integrated in vitro testing strategies (ITS) aiming at reducing and replacing animal experimentation.

    Science.gov (United States)

    De Wever, Bart; Fuchs, Horst W; Gaca, Marianna; Krul, Cyrille; Mikulowski, Stan; Poth, Albrecht; Roggen, Erwin L; Vilà, Maya R

    2012-04-01

    At the IVTIP (in vitro testing industrial platform) meeting of November 26th 2009 entitled 'Toxicology in the 21st century ('21C')--working our way towards a visionary reality' all delegates endorsed the emerging concept of the '21C' vision as the way forward to enable a thorough, reliable and systematic approach to future toxicity testing without the use of animals. One of the emerging concepts focused on integrating a defined number of tests modelling in vivo-relevant and well-characterised toxicity pathways representing mechanistic endpoints. At this meeting the importance of Integrated Testing Strategies (ITS) as tools towards reduction and eventually replacement of the animals currently used for hazard identification and risk assessment was recognised. A follow-up IVTIP Spring 2010 meeting entitled 'Integrated In Vitro Testing Strategies (ITS)--Implementation Challenges' was organised to address pending questions about ITS. This report is not a review of the ITS literature, but a summary of the discussions triggered by presented examples on how to develop and implement ITS. Contrasts between pharmaceutical and chemical industry, as well as a list of general but practical aspects to be considered while developing an ITS emerged from the discussions. In addition, current recommendations on the validation of ITS were discussed. In conclusion, the outcome of this workshop improved the understanding of the participants of some important factors that may impact the design of an ITS in function of its purpose (e.g., screening, or early decision making versus regulatory), the context in which they need to be applied (e.g., ICH guidelines, REACH) and the status and quality of the available tools. A set of recommendations of best practices was established and the importance of the applicability of the individual tests as well as the testing strategy itself was highlighted. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Toxicity of the mycotoxin citrinin and its metabolite dihydrocitrinone and of mixtures of citrinin and ochratoxin A in vitro.

    Science.gov (United States)

    Föllmann, Wolfram; Behm, Claudia; Degen, Gisela H

    2014-05-01

    Citrinin (CIT) and ochratoxin A (OTA) are mycotoxins produced by several species of the genera Aspergillus, Penicillium and Monascus. Both can be present as contaminants in various food commodities and in animal feed. The occurrence and toxicity of OTA and human exposure have been intensively studied, but for CIT such data are scarce by comparison. Recently, dihydrocitrinone (DH-CIT) was detected as main metabolite of CIT in human urine, and co-occurrence of CIT and OTA was shown in human blood plasma (Blaszkewicz et al. in Arch Toxicol 87:1087-1094, 2013). In light of these new findings, we have now investigated the toxicity of the metabolite DH-CIT in comparison with CIT and analysed the effects of mixtures of CIT and OTA in vitro. The cytotoxic potency of DH-CIT (IC50 of 320/200 μM) was distinctly lower compared with CIT (IC50 of 70/62 μM) after treatment of V79 cells for 24 and 48 h. Whereas CIT induced a concentration-dependent increase in micronucleus frequencies at concentrations ≥30 μM, DH-CIT showed no genotoxic effect up to 300 μM. Thus, conversion of CIT to DH-CIT in humans can be regarded as a detoxification step. Mixtures of CIT and OTA exerted additive effects in cytotoxicity assays. The effect of CIT and OTA mixtures on induction of micronuclei varied dependent on the used concentrations between additive for low μM concentrations and more-than-additive for high μM concentrations. Effects on cell cycle were mostly triggered by OTA when both mycotoxins were used in combination. The implications of our and related in vitro studies are discussed with respect to in vivo concentrations of CIT and OTA, which are found in animals and in humans.

  18. Evaluation of ability of reference toxicity tests to identify stress in laboratory populations of the amphipod Hyalella azteca

    Science.gov (United States)

    McNulty, E.W.; Dwyer, F.J.; Ellersieck, Mark R.; Greer, E.I.; Ingersoll, C.G.; Rabeni, C.F.

    1999-01-01

    Standard methods for conducting toxicity tests imply that the condition of test organisms can be established using reference toxicity tests. However, only a limited number of studies have evaluated whether reference toxicity tests can actually be used to determine if organisms are in good condition at the start of a test. We evaluated the ability of reference toxicants to identify stress associated with starvation in laboratory populations of the amphipod Hyalella azteca using acute toxicity tests and four reference toxicants: KCl, CdCl2, sodium pentachlorophenate (NaPCP), and carbaryl. Stress associated with severe starvation was observed with exposure of amphipods to carbaryl or NaPCP but not with exposure to KCl or CdCl2 (i.e., lower LC50 with severe starvation). Although the LC50s for NaPCP and carbaryl were statistically different between starved and fed amphipods, this difference may not be biologically significant given the variability expected in acute lethality tests. Stress associated with sieving, heat shock, or cold shock of amphipods before the start of a test was not evident with exposure to carbaryl or KCl as reference toxicants. The chemicals evaluated in this study provided minimal information about the condition of the organisms used to start a toxicity test. Laboratories should periodically perform reference toxicity tests to assess the sensitivity of life stages or strains of test organisms. However, use of other test acceptability criteria required in standard methods such as minimum survival, growth, or reproduction of organisms in the control treatment at the end of a test, provides more useful information about the condition of organisms used to start a test compared to data generated from reference toxicity tests.

  19. Toxicity testing and drug screening using iPSC-derived hepatocytes, cardiomyocytes, and neural cells.

    Science.gov (United States)

    Csöbönyeiová, Mária; Polák, Štefan; Danišovič, L'uboš

    2016-07-01

    Unexpected toxicity in areas such as cardiotoxicity, hepatotoxicity, and neurotoxicity is a serious complication of clinical therapy and one of the key causes for failure of promising drug candidates in development. Animal studies have been widely used for toxicology research to provide preclinical security evaluation of various therapeutic agents under development. Species differences in drug penetration of the blood-brain barrier, drug metabolism, and related toxicity contribute to failure of drug trials from animal models to human. The existing system for drug discovery has relied on immortalized cell lines, animal models of human disease, and clinical trials in humans. Moreover, drug candidates that are passed as being safe in the preclinical stage often show toxic effects during the clinical stage. Only around 16% drugs are approved for human use. Research on induced pluripotent stem cells (iPSCs) promises to enhance drug discovery and development by providing simple, reproducible, and economically effective tools for drug toxicity screening under development and, on the other hand, for studying the disease mechanism and pathways. In this review, we provide an overview of basic information about iPSCs, and discuss efforts aimed at the use of iPSC-derived hepatocytes, cardiomyocytes, and neural cells in drug discovery and toxicity testing.

  20. Toxicological assessment of heavy straight run naphtha in a repeated dose/reproductive toxicity screening test.

    Science.gov (United States)

    McKee, Richard H; Steup, David; Schreiner, Ceinwen; Podhasky, Paula; Malley, Linda A; Roberts, Linda

    2014-01-01

    Gasoline blending stocks (naphthas) are comprised of normal, iso- and cycloparaffins and aromatic hydrocarbons with carbon numbers ranging from C4 to C12. Heavy straight run naphtha (HSRN, CAS number 64741-41-9) was selected for toxicity screening because substances of this type contain relatively high levels (28%) of cycloparaffins by comparison to other naphtha streams and the data complement toxicity information on other gasoline blending streams. Rats were exposed by inhalation to wholly vaporized material at levels of approximately 100, 500, or 3000 parts per million (ppm) daily to screen the potential for systemic toxicity, neurotoxicity, reproductive toxicity, and developmental effects to postnatal day 4. All animals survived the treatment period. Principal effects of repeated exposure included increased liver weights in males and females, increased kidney weights in males, and histological changes in the thyroid, secondary to liver enzyme induction. These changes were not considered to be toxicologically meaningful and are not relevant to humans. There were no treatment-related effects in functional observation tests or motor activity; no significant reductions in fertility or changes in other reproductive parameters; and no evidence of developmental toxicity in offspring. The overall no observed adverse effect concentration was 3000 ppm (approximately 13, 600 mg/m(3)). In conclusion the HSRN effects on liver and kidney are consistent with the results of other studies of volatile fractions or other naphthas or formulated gasoline, and there were no HSRN effects on neurological developmental or reproductive parameters.

  1. Critique on the use of the standardized avian acute oral toxicity test for first generation anticoagulant rodenticides

    Science.gov (United States)

    Vyas, Nimish B.; Rattner, Barnett A.

    2012-01-01

    Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant's mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen is much different than that used in the standardized acute oral toxicity test methodology. Median lethal dose values derived from standardized acute oral toxicity tests underestimate the environmental hazard and risk of FGARs. Caution is warranted when FGAR toxicity, physiological effects, and pharmacokinetics derived from standardized acute oral toxicity testing are used for forensic confirmation of the cause of death in avian mortality incidents and when characterizing FGARs' risks to free-ranging birds.

  2. Evaluation of genotoxicity and subclinical toxicity of Agaricus blazei Murrill in the Ames test and in histopathological and biochemical analysis.

    Science.gov (United States)

    Chang, Jin-Biou; Lu, Hsu-Feng; Liao, Nien-Chieh; Lee, Ching-Sung; Yeh, Ming-Yang; Liu, Chi-Ming; Chung, Ming-Teng; Man-Kuan, Au; Lin, Jen-Jyh; Wu, Ming-Fang; Chung, Jing-Gung

    2012-01-01

    This study was conducted in order to assess the safety and tolerability of Agaricus blazei Murrill (ABM) in general toxicological studies by Ames tests in vitro and in 28-day feeding toxicity experiments. There were no dose-dependent increases or decreases in the number of revertant colonies both with and without metabolic activation in Ames tests. Doses of 10, 5 and 0.1 mg/per mouse of ABM daily were administered by oral gavage to mice (n=10) for 28 days. The effects on clinical observations, clinical pathology, and histopathology were evaluated. There were no significant changes in the brain, heart, kidney, liver, spleen, adrenal gland, testes or ovaries visually. With increasing doses, male and female treated mice did not show any gradual elevation of serum concentration in any of the nine items we examined, except for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in females. The AST levels of the treatment by medium or high dose and the ALT levels of the treatment by high dose in females were abnormal in comparison to those of the baseline control group, with significant differences. On studying the histological changes in mice, tissue sections of negative control and experimental groups exhibited no apparent pathological alterations. In summary, the Ames test, pathology determinations, biochemical analysis and routine blood parameters were all normal, except for AST and ALT in females. Results showed that the statistical differences observed in one sex were not observed in the other and were not dose dependent.

  3. Comparative in vitro toxicity of nitrosamines and nitramines associated with amine-based carbon capture and storage.

    Science.gov (United States)

    Wagner, Elizabeth D; Osiol, Jennifer; Mitch, William A; Plewa, Michael J

    2014-07-15

    Amine-based CO2 capture is a prime contender for the first full-scale implementation of CO2 capture at fossil fuel-fired power plants postcombustion. However, the formation of potentially carcinogenic N-nitrosamines and N-nitramines from reactions of flue gas NOx with the amines presents a potential risk for contaminating airsheds and drinking water supplies. Setting regulatory emission limits is hampered by the dearth of toxicity information for the N-nitramines. This study employed quantitative in vitro bioassays for mutagenicity in Salmonella typhimurium, and chronic cytotoxicity and acute genotoxicity in Chinese hamster ovary (CHO) cells to compare the toxicity of analogous N-nitrosamines and N-nitramines relevant to CO2 capture. Although the rank order was similar for genotoxicity in CHO cells and mutagenicity in S. typhimurium, the Salmonella assay was far more sensitive. In general, mutagenicity was higher with S9 hepatic microsomal activation. The rank order of mutagenicity was N-nitrosodimethylamine (NDMA)>N-nitrosomorpholine>N-nitrodimethylamine>1,4-dinitrosopiperazine>N-nitromorpholine>1,4-dinitropiperazine>N-nitromonoethanolamine>N-nitrosodiethanolamine>N-nitrodiethanolamine. 1-Nitrosopiperazine and 1-nitropiperazine were not mutagenic. Overall, N-nitrosamines were ∼15-fold more mutagenic than their N-nitramine analogues.

  4. In vitro toxicity assessment of three hydroxylated fullerenes in human skin cells.

    Science.gov (United States)

    Saathoff, J G; Inman, A O; Xia, X R; Riviere, J E; Monteiro-Riviere, N A

    2011-12-01

    Carbon fullerenes possess unique properties and their interactions with biomolecules have widespread applications. Functionalization of fullerenes with hydroxyl groups (fullerenols) can increase the solubility and potential for cellular interaction, but the health and safety effects of varying degrees of fullerene hydroxylation in biological systems is poorly understood. Existing reports regarding the toxicity and inflammatory potential of fullerenols give conflicting conclusions. To further elucidate the potential for toxicity of fullerenols, human epidermal keratinocytes (HEK) were exposed to fullerenols (low (C60(OH)20), medium (C60(OH)24), and high (C60(OH)32)) at concentrations ranging from 0.000544-42.5 μg/ml for 24 and 48 h. A statistically significant (pfullerenes caused no cytotoxicity or inflammation up to 8.55 μg/ml. These findings suggest that extrapolation across similar NP will be dependent upon surface chemistry and concentration which may affect the degree of agglomeration and thus biological effects. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Toxicity of polyhexanide and hydrogen peroxide on human chondrocytes in vitro.

    Science.gov (United States)

    Röhner, Eric; Seeger, Joern B; Hoff, Paula; Dähn-Wollenberg, Stephanie; Perka, Carsten; Matziolis, Georg

    2011-07-07

    The treatment of acute joint infections has an important impact on long-term outcome and remains an unsolved problem. The most frequent bacteria are staphylococci, streptococci, and gram-negative bacteria. In septic surgery, polyhexanide and hydrogen peroxide are the most frequently used local antiseptics. The aim of this study was to examine the hypothesis that antiseptics induce cell death of human chondrocytes after a short incubation time.Human chondrocytes were treated with different concentrations of polyhexanide and hydrogen peroxide. Toxicity analysis was determined by visualization of cell structure using light microscopy, lactate dehydrogenase release, and determination of living and total cell numbers after addition of polyhexanide and hydrogen peroxide. Light microscopic data revealed a defect cell structure after addition of both antiseptics. Lactate dehydrogenase activity showed a significant increase of enzyme expression after a short incubation with polyhexanide. The determination of vital chondrocytes showed a significant decrease of vital and total cell numbers after addition with polyhexanide and hydrogen peroxide.Both antiseptic solutions induce significant cell death of human chondrocytes after a short incubation time. Polyhexanide possibly has more toxic potential than hydrogen peroxide against human chondrocytes after an application >15 minutes. Therefore, both substances should only be applied for a short time (<15 minutes) and the joint irrigated to wash out the antiseptic substance prior to wound closure. Copyright 2011, SLACK Incorporated.

  6. In vitro toxic effects of reduced graphene oxide nanosheets on lung cancer cells

    Science.gov (United States)

    Tabish, Tanveer A.; Pranjol, Md Zahidul I.; Hayat, Hasan; Rahat, Alma A. M.; Abdullah, Trefa M.; Whatmore, Jacqueline L.; Zhang, Shaowei

    2017-12-01

    The intriguing properties of reduced graphene oxide (rGO) have paved the way for a number of potential biomedical applications such as drug delivery, tissue engineering, gene delivery and bio-sensing. Over the last decade, there have been escalating concerns regarding the possible toxic effects, behaviour and fate of rGO in living systems and environments. This paper reports on integrative chemical-biological interactions of rGO with lung cancer cells, i.e. A549 and SKMES-1, to determine its potential toxicological impacts on them, as a function of its concentration. Cell viability, early and late apoptosis and necrosis were measured to determine oxidative stress potential, and induction of apoptosis for the first time by comparing two lung cancer cells. We also showed the general trend between cell death rates and concentrations for different cell types using a Gaussian process regression model. At low concentrations, rGO was shown to significantly produce late apoptosis and necrosis rather than early apoptotic events, suggesting that it was able to disintegrate the cellular membranes in a dose dependent manner. For the toxicity exposures undertaken, late apoptosis and necrosis occurred, which was most likely resultant from limited bioavailability of unmodified rGO in lung cancer cells.

  7. Use of cortical neuronal networks for in vitro material biocompatibility testing.

    Science.gov (United States)

    Charkhkar, Hamid; Frewin, Christopher; Nezafati, Maysam; Knaack, Gretchen L; Peixoto, Nathalia; Saddow, Stephen E; Pancrazio, Joseph J

    2014-03-15

    Neural interfaces aim to restore neurological function lost during disease or injury. Novel implantable neural interfaces increasingly capitalize on novel materials to achieve microscale coupling with the nervous system. Like any biomedical device, neural interfaces should consist of materials that exhibit biocompatibility in accordance with the international standard ISO10993-5, which describes in vitro testing involving fibroblasts where cytotoxicity serves as the main endpoint. In the present study, we examine the utility of living neuronal networks as functional assays for in vitro material biocompatibility, particularly for materials that comprise implantable neural interfaces. Embryonic mouse cortical tissue was cultured to form functional networks where spontaneous action potentials, or spikes, can be monitored non-invasively using a substrate-integrated microelectrode array. Taking advantage of such a platform, we exposed established positive and negative control materials to the neuronal networks in a consistent method with ISO 10993-5 guidance. Exposure to the negative controls, gold and polyethylene, did not significantly change the neuronal activity whereas the positive controls, copper and polyvinyl chloride (PVC), resulted in reduction of network spike rate. We also compared the functional assay with an established cytotoxicity measure using L929 fibroblast cells. Our findings indicate that neuronal networks exhibit enhanced sensitivity to positive control materials. In addition, we assessed functional neurotoxicity of tungsten, a common microelectrode material, and two conducting polymer formulations that have been used to modify microelectrode properties for in vivo recording and stimulation. These data suggest that cultured neuronal networks are a useful platform for evaluating the functional toxicity of materials intended for implantation in the nervous system. © 2013 Elsevier B.V. All rights reserved.

  8. Influence of potentially confounding factors on sea urchin porewater toxicity tests.

    Science.gov (United States)

    Carr, R S; Biedenbach, J M; Nipper, M

    2006-11-01

    The influence of potentially confounding factors has been identified as a concern for interpreting sea urchin porewater toxicity test data. The results from >40 sediment-quality assessment surveys using early-life stages of the sea urchin Arbacia punctulata were compiled and examined to determine acceptable ranges of natural variables such as pH, ammonia, and dissolved organic carbon on the fertilization and embryological development endpoints. In addition, laboratory experiments were also conducted with A. punctulata and compared with information from the literature. Pore water with pH as low as 6.9 is an unlikely contributor to toxicity for the fertilization and embryological development tests with A. punctulata. Other species of sea urchin have narrower pH tolerance ranges. Ammonia is rarely a contributing factor in pore water toxicity tests using the fertilization endpoint, but the embryological development endpoint may be influenced by ammonia concentrations commonly found in porewater samples. Therefore, ammonia needs to be considered when interpreting results for the embryological development test. Humic acid does not affect sea urchin fertilization at saturation concentrations, but it could have an effect on the embryological development endpoint at near-saturation concentrations. There was no correlation between sediment total organic carbon concentrations and porewater dissolved organic carbon concentrations. Because of the potential for many varying substances to activate parthenogenesis in sea urchin eggs, it is recommended that a no-sperm control be included with every fertilization test treatment.

  9. 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.

    Science.gov (United States)

    Kirkland, David; Reeve, Lesley; Gatehouse, David; Vanparys, Philippe

    2011-03-18

    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

  10. A comparison of in vitro toxicities of cigarette smoke condensate from Eclipse cigarettes and four commercially available ultra low-"tar" cigarettes.

    Science.gov (United States)

    Foy, J W D; Bombick, B R; Bombick, D W; Doolittle, D J; Mosberg, A T; Swauger, J E

    2004-02-01

    Eclipse is a cigarette that primarily heats rather than burns tobacco. R.J. Reynolds Tobacco Company (RJRT) has previously reported the results of in vitro toxicity studies comparing Eclipse with University of Kentucky 1R5F and 1R4F reference cigarettes. To characterize the differences between Eclipse and very low yielding/ultra low-"tar" (vULT) tobacco-burning cigarettes, RJRT conducted a comparative evaluation of the genotoxicity and cytotoxicity of mainstream cigarette smoke condensate (CSC) from Eclipse and three vULT tobacco-burning cigarettes (Now 83 Box, Merit Ultima and Carlton Soft Pack) as well as the leading ultra low-"tar" (ULT) brandstyle (Marlboro Ultra Lights) under four smoking regimens: (1) FTC-35 ml puff volume every 60 s for a 2 s duration (35/60/2); (2) 50/30/2, 0% vents blocked; (3) Massachusetts-45/30/2, 50% vents blocked; (4) Canadian-55/30/2, 100% vents blocked. Ames testing indicated that Eclipse CSC was less (Pmutagenic than CSC from the four cigarettes under all smoking regimens when compared on a revertants per mg Total Particulate Matter (TPM) basis. When mutagenicity was calculated on a revertants per cigarette basis the mutagenicity of Eclipse CSC was lower (Pmutagenicity of Merit Ultima, Carlton Soft Pack, and Marlboro Ultra Lights, regardless of the puffing regimen. On a per cigarette basis, the calculated mutagenicity of Eclipse was higher (PTPM/ml media) than the CSC from the four test cigarettes regardless of the regimen used. Collectively, these data demonstrate that the toxicity of CSC from Eclipse is significantly reduced relative to the activity of CSC from the tested vULT cigarettes and the Marlboro Ultra Lights.

  11. Comparison of toxicity effects of ropivacaine, bupivacaine, and lidocaine on rabbit intervertebral disc cells in vitro.

    Science.gov (United States)

    Cai, Xian-Yi; Xiong, Li-Ming; Yang, Shu-Hua; Shao, Zeng-Wu; Xie, Mao; Gao, Fei; Ding, Fan

    2014-03-01

    It has been shown that bupivacaine, the most commonly used local anesthetic to relieve or control pain in interventional spine procedures, is cytotoxic to intervertebral disc (IVD) cells in vitro. However, some other common local anesthetics, such as ropivacaine and lidocaine, are also frequently used in the treatment of spine-related pain, and the potential effects of these agents remain unclear. The purpose of this study was to evaluate the effect of various local anesthetics on rabbit IVD cells in vitro and further compare the cytotoxicity of ropivacaine, bupivacaine, lidocaine, and saline solution control. Controlled laboratory study. Rabbit annulus fibrosus (AF) and nucleus pulposus (NP) cells were isolated from Japanese white rabbits. Both AF and NP cells at the second generation maintained in monolayer were exposed to various concentrations of local anesthetics (eg, bupivacaine) or different durations of exposure and evaluated for cell viability by use of cell counting kit-8 (CCK-8). In addition, to compare the cytotoxicity of ropivacaine, bupivacaine, lidocaine, and saline solution control in commercial concentration, the viability was analyzed by flow cytometry after 60-minute exposure, and the morphologic changes were observed by the phase-contrast microscopy. Apoptosis and necrosis of IVD cells were confirmed by using fluorescence microscopy with double staining of Hoechst 33342 and propidium iodide. Rabbit IVD cell death demonstrated a time and dose dependence in response to bupivacaine and lidocaine. However, ropivacaine only exerted a significant time-dependent effect on IVD cells. There was no significant difference in IVD viability after treatment with different doses of ropivacaine. In addition, the results showed that lidocaine was the most toxic of the three local anesthetics and that ropivacaine presented less cytotoxicity than lidocaine and bupivacaine. Fluorescence microscopy also confirmed that the short-term toxic effect of local

  12. Nanoparticle-protein corona in invertebrate in vitro testing

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Miclaus, Teodora; Scavenius, Carsten

    2013-01-01

    , and the primary cells were thus exposed to silver nanoparticles with pre-formed corona of serum albumin (a major serum protein). Here we have profiled proteins forming the hard corona around silver nanoparticles (OECD reference materials, 15 nm and 75 nm) using gel electrophoresis techniques to identify proteins...... for evaluation of the protein corona in invertebrate in vitro setting....

  13. Toxicity Testing of Restorative Dental Materials Using Brine Shrimp Larvae (Artemia salina

    Directory of Open Access Journals (Sweden)

    Manar M. Milhem

    2008-08-01

    Full Text Available This study investigated the effect of extracts of different composites, glass ionomer cement (GICs and compomers on the viability of brine shrimp larvae. Ethanolic extracts of four dental composites (Z-100; Solitaire 2; Filtek P60 and Synergy, a conventional GIC (Ketac-Fil, a resin-modified glass ionomer cement (Vitremer, two compomers (F2000; Dyract AP, and a flowable compomer (Dyract Flow were prepared from each material. Following evaporation of the ethanol, the extracts were resuspended in distilled water, which was then used to test the effects on the viability of brine shrimp larvae. For the composites, the extract of Synergy was the least toxic (88% viability followed by the extracts of Solitaire 2, Z100 and P60 (75%, 67.5% and 50% viability, respectively. One-way ANOVA revealed highly significant differences between the resin composite materials (p<0.001. Follow-up comparison between the composite groups by Tukey's pairwise multiple-comparison test (α =0.05 showed that the extract of Synergy was significantly less toxic than the extracts of all the other materials except that of Solitaire 2. The compomers showed 100% lethality, while the percentage of viable larvae for the extracts of Ketac-Fil, and Vitremer were 32.3%, and 37.0%, respectively. One-way ANOVA revealed highly significant differences between the groups of materials (p<0.001. Follow-up comparison between the groups by Tukey's test (α = 0.05 showed that the toxic effect of the extracts of the compomers were significantly greater than that of Ketac-Fil, and Vitremer. The differences in the toxic effects of Vitremer and Ketac-Fil were not statistically significant. In conclusion, the toxicity of composite materials varied according to their chemical composition. Compomers were the most lethal materials to brine shrimp larvae followed by GICs and then composites.

  14. Comparative analysis of tumor spheroid generation techniques for differential in vitro drug toxicity

    Science.gov (United States)

    Raghavan, Shreya; Rowley, Katelyn R.; Mehta, Geeta

    2016-01-01

    Multicellular tumor spheroids are powerful in vitro models to perform preclinical chemosensitivity assays. We compare different methodologies to generate tumor spheroids in terms of resultant spheroid morphology, cellular arrangement and chemosensitivity. We used two cancer cell lines (MCF7 and OVCAR8) to generate spheroids using i) hanging drop array plates; ii) liquid overlay on ultra-low attachment plates; iii) liquid overlay on ultra-low attachment plates with rotating mixing (nutator plates). Analysis of spheroid morphometry indicated that cellular compaction was increased in spheroids generated on nutator and hanging drop array plates. Collagen staining also indicated higher compaction and remodeling in tumor spheroids on nutator and hanging drop arrays compared to conventional liquid overlay. Consequently, spheroids generated on nutator or hanging drop plates had increased chemoresistance to cisplatin treatment (20-60% viability) compared to spheroids on ultra low attachment plates (10-20% viability). Lastly, we used a mathematical model to demonstrate minimal changes in oxygen and cisplatin diffusion within experimentally generated spheroids. Our results demonstrate that in vitro methods of tumor spheroid generation result in varied cellular arrangement and chemosensitivity. PMID:26918944

  15. History and sensitivity comparison of the Spirodela polyrhiza microbiotest and Lemna toxicity tests

    Directory of Open Access Journals (Sweden)

    Baudo R.

    2015-01-01

    Full Text Available The history of toxicity tests with duckweeds shows that these assays with free-floating aquatic angiosperms are gaining increasing attention in ecotoxicological research and applications. Standard tests have been published by national and international organizations, mainly with the test species Lemna minor and Lemna gibba. Besides the former two test species the great duckweed Spirodela polyrhiza is to date also regularly used in duckweed testing. Under unfavorable environmental conditions, the latter species produces dormant stages (turions and this has triggered the attention of two research groups from Belgium and Greece to jointly develop a “stock culture independent” microbiotest with S. polyrhiza. A 72 h new test has been worked out which besides its independence of stock culturing and maintenance of live stocks is very simple and practical to perform, and much less demanding in space and time than the conventional duckweed tests. Extensive International Interlaboratory Comparisons on the S. polyrhiza microbiotest showed its robustness and reliability and triggered the decision to propose this new assay to the ISO for endorsement and publication as a standard toxicity test for duckweeds. Sensitivity comparison of the 72 h S. polyrhiza microbiotest with the 7d L. minor assay for 22 compounds belonging to different groups of chemicals revealed that based on growth as the effect criterion both duckweed assays have a similar sensitivity. Taking into account its multiple advantages and assets, the S. polyrhiza microbiotest is a reliable and attractive alternative to the conventional duckweed tests.

  16. Discovery of potent, novel, non-toxic anti-malarial compounds via quantum modelling, virtual screening and in vitro experimental validation

    Directory of Open Access Journals (Sweden)

    Kaludov Nikola

    2011-09-01

    Full Text Available Abstract Background Developing resistance towards existing anti-malarial therapies emphasize the urgent need for new therapeutic options. Additionally, many malaria drugs in use today have high toxicity and low therapeutic indices. Gradient Biomodeling, LLC has developed a quantum-model search technology that uses quantum similarity and does not depend explicitly on chemical structure, as molecules are rigorously described in fundamental quantum attributes related to individual pharmacological properties. Therapeutic activity, as well as toxicity and other essential properties can be analysed and optimized simultaneously, independently of one another. Such methodology is suitable for a search of novel, non-toxic, active anti-malarial compounds. Methods A set of innovative algorithms is used for the fast calculation and interpretation of electron-density attributes of molecular structures at the quantum level for rapid discovery of prospective pharmaceuticals. Potency and efficacy, as well as additional physicochemical, metabolic, pharmacokinetic, safety, permeability and other properties were characterized by the procedure. Once quantum models are developed and experimentally validated, the methodology provides a straightforward implementation for lead discovery, compound optimizzation and de novo molecular design. Results Starting with a diverse training set of 26 well-known anti-malarial agents combined with 1730 moderately active and inactive molecules, novel compounds that have strong anti-malarial activity, low cytotoxicity and structural dissimilarity from the training set were discovered and experimentally validated. Twelve compounds were identified in silico and tested in vitro; eight of them showed anti-malarial activity (IC50 ≤ 10 μM, with six being very effective (IC50 ≤ 1 μM, and four exhibiting low nanomolar potency. The most active compounds were also tested for mammalian cytotoxicity and found to be non-toxic, with a

  17. Increased RO concentrate toxicity following application of antiscalants - acute toxicity tests with the amphipods Gammarus pulex and Gammarus roeseli.

    Science.gov (United States)

    Feiner, Mona; Beggel, Sebastian; Jaeger, Nadine; Geist, Juergen

    2015-02-01

    In reverse osmosis, a frequently used technology in water desalination processes, wastewater (RO concentrate) is generated containing the retained solutes as well as so-called antiscalants (AS), i.e. chemical substances that are commonly applied to prevent membrane-blocking. In this study, a risk assessment of a possible discharge of concentrate into a small stream was conducted. The acute toxicity of two concentrates containing two different ASs and of concentrate without AS to the amphipods Gammarus pulex and Gammarus roeseli was studied. Mortality of gammarids exposed to the concentrate without AS was not different to the control, whereas concentrates including ASs caused mortality rates up to 100% at the highest test concentrations after 168 h. Resulting EC50-values were 36.2-39.4% (v/v) after 96 h and 26.6-58.0% (v/v) after 168 h. These results suggest that the ecotoxicological relevance of antiscalants is greater than currently assumed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Toxicogenomics in vitro as an alternative tool for safety evaluation of petroleum substances and PAHs with regard to prenatal developmental toxicity

    NARCIS (Netherlands)

    Tsitou, Polyxeni; Heneweer, Marjoke; Boogaard, P.J.

    2015-01-01

    The REACH legislation requires chemicals - including petroleum substances - that are put on the EU market in quantities greater than 1000 tonnes/year, to be tested for prenatal developmental toxicity. This will require large numbers of animals since prenatal development toxicity testing is

  19. Drug solubilization and in vitro toxicity evaluation of lipoamino acid surfactants.

    Science.gov (United States)

    Ménard, Nathalie; Tsapis, Nicolas; Poirier, Cécile; Arnauld, Thomas; Moine, Laurence; Lefoulon, François; Péan, Jean-Manuel; Fattal, Elias

    2012-02-28

    To improve solubilization of a water insoluble anticancer drug, novel surfactants were synthesized. All surfactants derived from lysine, with a so-called nitrilo triacetic acid (NTA) polar head, and differed from the length and saturation degree of their hydrophobic moieties: C19:0-NTA, C20:4-NTA, C25:0-NTA and C25:4-NTA. Self-assembling properties and critical micellar concentration (CMC) values were determined using pyrene fluorescence and cytotoxicity using MTT and LDH assays on endothelial cells. Surfactant haemolytic activity and drug solubilization capacity were also evaluated. All surfactants self-assemble with low CMC values from 0.012 to 0.430 mg/mL. Cytotoxicity assays showed that C20:4-NTA and C25:0-NTA were less cytotoxic than polysorbate 80. Unsaturations and alkane chain length have a marked influence on toxicity. Saturated surfactants had a similar haemolytic activity, explained by their low CMC values and the linear configuration of their hydrophobic tail. C20:4-NTA and C25:4-NTA were less haemolytic than polysorbate 80. Furthermore, C19:0-NTA, C25:0-NTA and C25:4-NTA increased drug solubility from <0.15 μg/mL up to 7 mg/mL, with 46% (w/w) drug loading, due to their linear and flexible hydrophobic chain configuration, as evidenced by molecular modelling. Although these solubilizers are promising, a compromise between drug solubilization and toxicity remains to be found. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Staining and in vitro toxicity of dithizone with canine, porcine, and bovine islets.

    Science.gov (United States)

    Clark, S A; Borland, K M; Sherman, S D; Rusack, T C; Chick, W L

    1994-01-01

    Dithizone (DTZ) is a recognized diabetogenic agent in vivo, and a supravital stain commonly used for identification of islets to be used for transplantation. In the present studies, we compared DTZ staining of freshly isolated and cultured canine, bovine, and porcine islets, and the effect of DTZ on the function and viability of islets. Incubation with DTZ resulted in staining of canine and porcine islets, but no discernible staining with bovine islets. Insulin content of porcine, canine, and bovine islet was 2.0 +/- 0.2, 2.2 +/- 0.3, and 1.9 +/- 0.2 mU/EIN, indicating a lack of correspondence of DTZ staining and insulin content. Seven days of culture with canine islets resulted in > or = 50% reduction of DTZ stained cells. Exposure to DTZ at 50 micrograms/mL resulted in a maximal number of stained cells in preparations of purified islets (80-85%; counted after dispersion), a lower percentage of cells stained faintly at 20 micrograms/mL (50-55%), with no discernible staining at 10 micrograms/mL. Prolonged exposure of islets (4-48 h) to 20 micrograms/mL DTZ led to reduced insulin secretion and islet cell death. Incubation of canine or porcine islets with 100 micrograms/mL of DTZ for 0.5 h resulted in a dramatic loss of viability and diminished insulin secretory function, which was not reversed with continued culture. The concentration dependence of toxic effects paralleled the concentration dependence of cellular staining. The minimally effective staining concentration (20 micrograms/mL) also resulted in a loss of viability. An additional assessment of DTZ toxicity was made using the RIN-38 beta-cell line, which shows no discernible staining with DTZ.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Optimizing the performance of Hyalella azteca in chronic toxicity tests: Results of feeding studies with various foods and feeding regimes

    Science.gov (United States)

    The freshwater amphipod Hyalella azteca is a common organism used for sediment toxicity testing in the United States and elsewhere. Standard methods for 10-d and 42-d toxicity tests with H. azteca were last revised and published by USEPA/ASTM in 2000. Under the methods in the man...

  2. Multivariate toxicity profiles and QSAR modelling of NDL-PCBs – an investigation of in vitro screening data from ultra-pure congeners

    NARCIS (Netherlands)

    Stenberg, M.; Hamers, T.H.M.; Machala, M.; Fonnum, F.; Stenius, U.; Al Anati, L.; van Duursen, M.; Westerink, R.H.S.; Fernandes, E.C.A.; Andersson, P.L.

    2011-01-01

    The non-dioxin-like PCBs (NDL-PCBs) found in food and human samples have a complex spectrum of adverse effects, but lack a detailed risk assessment. The toxicity profiles of 21 carefully selected PCBs (19 NDL-PCBs) were identified by in vitro screening in 17 different assays on specific endpoints

  3. Toxicity assessment of aggregated/agglomerated cerium oxide nanoparticles in an in vitro 3D airway model: The influence of mucociliary clearance

    NARCIS (Netherlands)

    Kuper, C.F.; Gröllers-Mulderij, M.; Maarschalkerweerd, T.; Meulendijks, N.M.M.; Reus, A.; Acker, F. van; Zondervan-van den Beuken, E.K.; Wouters, M.E.L.; Bijlsma, S.; Kooter, I.M.

    2014-01-01

    We investigated the toxicity of aggregated nanoparticles of cerium oxide (CeO2) using an in vitro 3D human bronchial epithelial model that included a mucociliary apparatus (MucilAir™). CeO2 was dispersed in saline and applied to the apical surface of the model. CeO2 did not induce distinct effects

  4. The Role of Feature Selection and Statistical Weighting in Predicting In Vivo Toxicity Using In Vitro Assay and QSAR Data (SOT)

    Science.gov (United States)

    Our study assesses the value of both in vitro assay and quantitative structure activity relationship (QSAR) data in predicting in vivo toxicity using numerous statistical models and approaches to process the data. Our models are built on datasets of (i) 586 chemicals for which bo...

  5. Burrowing mayfly Ephemera orientalis (Ephemeroptera: Ephemeridae) as a new test species for pesticide toxicity.

    Science.gov (United States)

    Mo, Hyoung-Ho; Kim, Yongeun; Lee, Yun-Sik; Bae, Yeon Jae; Khim, Jong Seong; Cho, Kijong

    2016-09-01

    The potential of mayfly Ephemera orientalis McLachlan eggs and first-instar larvae in ecotoxicological testing was investigated. Both stages of E. orientalis showed high tolerance to various environmental variables, such as water temperature, pH, water hardness, and dissolved organic carbon. Toxicological assays were conducted with three insecticides (emamectin benzoate, endosulfan, and cypermethrin), one fungicide (mancozeb), and one herbicide (paraquat dichloride). The two toxicity endpoints for the assay were the 14-day egg median hatching rate (EHC50) in static and renewal exposure systems and 24-h median larval mortality (LC50). Cypermethrin was the most toxic to both eggs (EHC50 in static system = 36.9 μg/L; EHC50 in renewal system < 0.15 μg/L) and larvae (LC50 = 4.5 μg/L), and paraquat dichloride was the least toxic to eggs (EHC50 in static system = 54,359.8 μg/L; EHC50 in renewal system = 49541.3 μg/L) and larvae (LC50 = 9259.5 μg/L). The results were compared to literature data of Daphnia magna Straus and Cloeon dipterum Linnaeus to determine its relative sensitivity to pesticides. These three species had different toxicities to the tested pesticides, especially according to the exposure system. E. orientalis eggs in the static system were found to be less sensitive were D. magna and C. dipterum, but eggs in the renewal system and larvae had similar or higher sensitivities to the tested pesticides. The results revealed that this species has potential for use in ecotoxicological testing of pesticides. Because of its geographic distribution, E. orientalis may be used as an alternative or complementary test species for ecotoxicological studies in Northeast Asian countries, where natural populations of the international standard species, D. magna, are rarely found.

  6. Modified whole effluent toxicity test to assess and decouple wastewater effects from environmental gradients.

    Directory of Open Access Journals (Sweden)

    Sebastián Sauco

    Full Text Available Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM to assess and decouple those effects. We tested this approach, analyzing the lethal effects of wastewater on a marine sandy beach bivalve affected by an artificial canal freshwater discharge used for rice crops irrigation. To this end, we compared bivalve mortality between canal water dilutions (CWd and salinity controls (SC: without canal water. CWd were prepared by diluting the water effluent (sampled during the pesticide application period with artificial marine water. The salinity gradient was included in the design by achieving the same final salinities in both CWd and SC, allowing us to account for the effects of salinity by including this variable as a random factor in the GLMM. Our approach detected significantly higher mortalities in CWd, indicating potential toxic effects of the effluent discharge. mWET represents an improvement over the internationally standardized WET tests, since it considers environmental variability and uses appropriate statistical analyses.

  7. Test Results for a Non-toxic, Dual Thrust Reaction Control Engine

    Science.gov (United States)

    Robinson, Philip J.; Veith, Eric M.; Turpin, Alicia A.

    2005-01-01

    A non-toxic, dual thrust reaction control engine (RCE) was successfully tested over a broad range of operating conditions at the Aerojet Sacramento facility. The RCE utilized LOX/Ethanol propellants; and was tested in steady state and pulsing modes at 25-lbf thrust (vernier) and at 870-lbf thrust (primary). Steady state vernier tests vaned chamber pressure (Pc) from 0.78 to 5.96 psia, and mixture ratio (MR) from 0.73 to 1.82, while primary steady state tests vaned Pc from 103 to 179 psia and MR from 1.33 to 1.76. Pulsing tests explored EPW from 0.080 to 10 seconds and DC from 5 to 50 percent at both thrust levels. Vernier testing accumulated a total of 6,670 seconds of firing time, and 7,215 pulses, and primary testing accumulated a total of 2,060 seconds of firing time and 3,646 pulses.

  8. Marine and estuarine porewater toxicity testing -- species and end point comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.S.; Chapman, D.C.; Biedenbach, J.M.; Robertson, L. [NBS, Corpus Christi, TX (United States). NFCR Field Research Station

    1994-12-31

    As part of their continuing development and evaluation of the porewater toxicity test approach for assessing the quality of marine and estuarine sediments, a variety of studies involving species and endpoint comparisons as well as validation studies have recently been conducted. The results from numerous extensive sediment quality assessment surveys have demonstrated that porewater toxicity tests are considerably more sensitive than the standard solid-phase tests and invariably exhibit a higher degree of concordance with sediment quality assessment guidelines than the standard tests. Species that have been evaluated for use in testing marine and estuarine pore water include a life-cycle test with the polychaete Dinophilus gyrociliatus, survival and hatching success with embryo-larval stages of red drum Sciaaenops ocellatus, survival of nauplii stages of the harpacticoid copepod Longipedia sp., and three different assays (fertilization, embryological development, and cytogenetic) with the sea urchin Arbacia punctulata. The different species and end points have been compared using sediment pore water from a variety of contaminated sites. Although the results of tests with the different species and end points were often comparable, in general, the sea urchin embryological development assay appears to be the most sensitive porewater test evaluated thus far in their laboratory.

  9. Handbook of acute toxicity of chemicals to fish and aquatic invertebrates : summaries of toxicity tests conducted at Columbia National Fisheries Research Laboratory, 1965-78

    Science.gov (United States)

    Johnson, W. Waynon; Finley, Mack T.

    1980-01-01

    Acute toxicity is a major subject of research at Columbia National Fisheries Research Laboratory for evaluating the impact of toxic chemicals on fishery resources. The Laboratory has played a leading role in developing research technology for toxicity testing and data interpretation. In 1965-78, more than 400 chemicals were tested against a variety of invertebrates and fish species representative of both cold- and warm-water climates.The use of acute toxicity tests for assessing the potential hazard of chemical contaminants to aquatic organisms is well documented (Boyd 1957; Henderson et al. 1960; Sanders and Cope 1966; Macek and McAllister 1970). Static acute toxicity tests provide rapid and (within limits) reproducible concentration-response curves for estimating toxic effects of chemicals on aquatic organisms. These tests provide a database for determining relative toxicity of a large number of chemicals to a variety of species and for estimating acute effects of chemical spills on natural aquatic systems; they also assist in determining priority and design of additional toxicity studies.Acute toxicity tests usually provide estimates of the exposure concentration causing 50% mortality (LC50) to test organisms during a specified period of time. For certain invertebrates, the effective concentration is based on immobilization, or some other identifiable endpoint, rather than on lethality. The application of the LC50 has gained acceptance among toxicologists and is generally the most highly rated test for assessing potential adverse effects of chemical contaminants to aquatic life (Brungs and Mount 1978; American Institute for Biological Sciences 1978a).The literature contains numerous papers dealing with the acute toxicity of chemicals to freshwater organisms. However, there is a tremendous need for a concise compendium of toxicity data covering a large variety of chemicals and test species. This Handbook is a compilation of a large volume of acute toxicity data

  10. The toxic effect of opioid analgesics on human sperm motility in vitro.

    Science.gov (United States)

    Xu, Bo; Wang, Zhi-Ping; Wang, Yan-Juan; Lu, Pei-Hua; Wang, Li-Jun; Wang, Xiao-Hai

    2013-04-01

    Opioid analgesics are the most common therapeutic analgesic for acute pain. In this study, the toxicological and pharmacological features of a group of opioid analgesics were characterized by the motility of human sperm. Aliquots of sperm were incubated with various concentrations of opioid analgesics in vitro. Computer-assisted sperm analysis was used to assess sperm motility at 15 minutes, 2 hours, and 4 hours after drug addition to the medium. Butorphanol and dezocine showed marked reduction of motility after incubation with sperm for 15 minutes. Butorphanol was more effective than dezocine in immobilizing sperm. Other opioids studied, such as fentanyl, alfentanil, and sufentanil, showed only partial inhibitory activity. Based on the data reported herein, we have found that butorphanol and dezocine exert a sperm-immobilizing effect. However, fentanyl, alfentanil, and sufentanil exhibit only partial inhibition of sperm motility. Given the increasing use of opioids and their potential effect on sperm motility, these findings are greatly relevant to male reproductive health.

  11. Biodegradable polymeric system for cisplatin delivery: Development, in vitro characterization and investigation of toxicity profile

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Noor; Khare, Vaibhav; Dubey, Ravindra; Saneja, Ankit [Formulation and Drug Delivery Division, CSIR-Indian Institute of Integrative Medicine, Jammu (India); Kushwaha, Manoj; Singh, Gurdarshan; Sharma, Neelam; Chandan, Balkrishan [PK-PD-Toxicology Division, CSIR-Indian Institute of Integrative Medicine, Jammu (India); Gupta, Prem N., E-mail: pngupta10@gmail.com [Formulation and Drug Delivery Division, CSIR-Indian Institute of Integrative Medicine, Jammu (India)

    2014-05-01

    Cisplatin is one of the most potent anticancer agent used in the treatment of various solid tumors, however, its clinical use is limited due to severe adverse effects including nephrotoxicity. In this investigation cisplatin loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles were developed and characterized for various in vitro characteristics including size distribution, zeta potential, drug loading and release profile. PLGA nanoparticles were successfully developed as investigated using scanning electron microscopy and exhibited average particles size and zeta potential as 284.8 nm and − 15.8 mV, respectively. Fourier transform infrared spectroscopy and differential scanning calorimetry indicated an absence of any polymer–drug interactions. Cisplatin nanoparticles exhibited in vitro anticancer activity against A549 cells comparable to that of cisplatin solution. The biodistribution study in mice indicated that the kidney cisplatin level was significantly (p < 0.01) lower with cisplatin nanoparticles than cisplatin solution. Following two cycles of cisplatin treatment, a week apart, blood urea nitrogen level was found to be higher in case of cisplatin solution as compared to cisplatin nanoparticles. Further, there was a significant (p < 0.01) increase in plasma creatinine level in case of cisplatin solution as compared to cisplatin nanoparticles. Histopathological examination of kidney from cisplatin nanoparticles treated group revealed no kidney damage, however, a sign of nephrotoxicity was observed in the case of cisplatin solution. The results suggest that PLGA nanoparticle based formulation could be a potential option for cisplatin delivery. - Highlights: • Cisplatin is detected by LCMS following complexation with DDTC. • Nanoparticles showed lower cisplatin accumulation in the kidney. • Nephrotoxicity was evaluated by BUN and creatinine level and by histopathology. • Nanoparticles exhibited lower nephrotoxicity.

  12. In vitro toxicity evaluation of Ti(4+)-stabilized γ-Bi2O3 sillenites.

    Science.gov (United States)

    Popescu, T; Lupu, A R; Feder, M; Tarabasanu-Mihaila, D; Teodorescu, V S; Vlaicu, A M; Diamandescu, L

    2014-12-01

    We report results regarding the in vitro toxicology of γ-Bi2O3 represented by its isomorphous phase Bi12TiO20 (γ-BTO). The γ-BTO microparticles were synthesized by two methods: coprecipitation from a bismuth nitrate-tetrabutyl titanate solution and solid state reaction of Bi2O3 and TiO2 oxides. The structural and morphological characteristics of the obtained materials were determined using X-ray diffraction (XRD), selected area electron diffraction (SAED), transmission (TEM) and scanning (SEM) electron microscopy. The elemental composition was investigated using energy dispersive spectrometry (EDS). The cytotoxicity and oxidative/nitrosative stress (intracellular reactive oxygen species (ROS) and nitric oxide (NO) release) induced by the studied microparticles in HepG2, SH-SY5Y and 3T3-L1 cell cultures were determined using the MTT, DCF-DA (2',7'-dichlorfluorescein-diacetate) and Griess methods respectively. Depending on the cell type and γ-BTO concentration, results showed only weak cytotoxic effects after 24h of γ-BTO exposure and cell proliferation effects for longer treatment times. Only reduced NO release increases (corresponding to high γ-BTO concentrations) were detected in case of SH-SY5Y and 3T3-L1 cells. The intracellular ROS production (higher for HepG2 cells) appeared inversely proportional to the γ-BTO concentration. The obtained results indicated a promising in vitro biocompatibility of γ-BTO and encourage further studies regarding its potential for biomedical applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. An integrated approach for detecting embryotoxicity and developmental toxicity of environmental contaminants using in vitro alternative methods.

    Science.gov (United States)

    Sogorb, Miguel A; Pamies, David; de Lapuente, Joaquín; Estevan, Carmen; Estévez, Jorge; Vilanova, Eugenio

    2014-10-15

    The main available alternatives for testing embryotoxicity are cellular tests with stem cells and in vitro-ex vivo tests with embryos. In cellular tests, the most developed alternative is the embryonic stem cell test, while the most developed tests involving embryos are the zebrafish and whole embryo culture test. They are technically more complex than cellular tests, but offer the advantage of determining the expectable phenotypic alteration caused by the exposure. Many efforts are currently being made, basically through proteomic and genomic approaches, in order to obtain improvements in predictivity of these tests. Development is a very complex process, and it is highly unlikely that a single alternative test can yield satisfactory performance with all types of chemicals. We propose a step-wise approach where model complexity, and consequently technical skills and economical costs, gradually increase if needed. The first level would be run short cellular assays to detect effects in early differentiation stages. The second level would involve longer cellular embryotoxicity tests to search embryotoxicants that have an effect on late differentiation stages. The third stage would consider tests with embryos because they allow the determination of hazards based on molecular and morphological alterations, and not only on differentiating cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Adjusting for mortality effects in chronic toxicity testing: Mixture model approach

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.C.D.; Smith, E.P.

    2000-01-01

    Chronic toxicity tests, such as the Ceriodaphnia dubia 7-d test are typically analyzed using standard statistical methods such as analysis of variance or regression. Recent research has emphasized the use of Poisson regression or more generalized regression for the analysis of the fecundity data from these studies. A possible problem in using standard statistical techniques is that mortality may occur from toxicant effects as well as reduced fecundity. A mixture model that accounts for fecundity and mortality is proposed for the analysis of data arising from these studies. Inferences about key parameters in the model are discussed. A joint estimate of the inhibition concentration is proposed based on the model. Confidence interval estimations via the bootstrap method is discussed. An example is given for a study involving copper and mercury.

  15. Thyroid in a jar: towards an integrated in vitro testing strategy for thyroid-active compounds

    NARCIS (Netherlands)

    Jomaa, B.

    2015-01-01

      Jomaa, B. (2015). Thyroid in a Jar: Towards an Integrated In Vitro Testing Strategy for Thyroid-Active Compounds. PhD thesis, Wageningen University, the Netherlands Abstract The aim of this thesis was to find in vitro and toxicogenomics-based alternatives to

  16. Genotoxicity test and subchronic toxicity study with Superba™ krill oil in rats

    OpenAIRE

    Robertson, Bruce; Burri, Lena; Berge, Kjetil

    2014-01-01

    The safety of krill oil was assessed in a subchronic toxicity study and in a genotoxicity test. In a 13-week study, rats were fed krill oil or control diets. There were no differences noted in body weight, food consumption or in the functional observation battery parameters in either gender. Differences in both haematology and clinical chemistry values were noted in the krill oil-treated groups. However these findings were of no toxicological significance. Significant decreases in absolute an...

  17. Effects of systematic variation in size and surface coating of silver nanoparticles on their in vitro toxicity to macrophage RAW 264.7 cells.

    Science.gov (United States)

    Makama, Sunday; Kloet, Samantha K; Piella, Jordi; van den Berg, Hans; de Ruijter, Norbert C A; Puntes, Victor F; Rietjens, Ivonne M C M; van den Brink, Nico W

    2017-11-02

    In literature, varying and sometimes conflicting effects of physicochemical properties of NPs are reported on their uptake and effects in organisms. To address this, small and medium sized (20 and 50 nm) AgNPs with specified different surface coating/charges were synthesized and used to systematically assess effects of NP-properties on their uptake and effects in vitro. AgNPs were fully characterized for charge and size distribution in both water and test media. Macrophage cells (RAW 264.7) were exposed to these AgNPs at different concentrations (0 - 200 µg/mL). Uptake dynamics, cell viability, induction of tumor necrosis factor (TNF)-α, adenosine triphosphate (ATP) production and reactive oxygen species (ROS) generation were assessed. Microscopic imaging of living exposed cells showed rapid uptake and subcellular cytoplasmic accumulation of AgNPs. Exposure to the tested AgNPs resulted in reduced overall viability. Influence of both size and surface coating (charge) was demonstrated, with the 20 nm sized AgNPs and BSA coated (negatively charged) AgNPs being slightly more toxic. On specific mechanisms of toxicity (TNF-α and ROS production) however, the AgNPs differed to a larger extent. The highest induction of TNF-α was found in cells exposed to the negatively charged AgNP_BSA, both sizes (80x higher than control). ROS induction was only significant with the 20 nm positively charged AgNP_Chit. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Evaluation of the toxicity of Araribá (Centrolobium tomentosum using brine Shrimp test

    Directory of Open Access Journals (Sweden)

    Roberto Carlos de Sá Silva

    2013-12-01

    Full Text Available Since the dawn of medicine, man has used natural products for the treatment of disease. There has been a recent increase in studies of the therapeutic characteristics plants in popular use in many places of the world. In this context, the species Centrolobium tomentosum, Fabaceae, known popularly as Araribá or Araruva, is used in Brazilian folk medicine as an astringent for wound treatment and bruises due to the large amount of tannins contained in the bark. This work used toxicity tests to assess the biological activity of ethanolic extracts from C. tomentosum with the specific objectives of obtaining concentrated extracts from the bark and wood of this species and determining the total phenols and tannins present in these extracts. We collected araribá samples in order to obtain ethanolic extracts through the percolation process. We then made a qualitative chemical identification of hydrolysable tannins and condensed tannins. We used the Folin-Ciocalteu method for the phenols quantification and the casein precipitation method for the tannins determination. The toxicity of extracts was evaluated using the brine shrimp bioassay (Artemia salina, in which the C. tomentosum bark extract showed moderate toxicity, with estimated LC50 = 416 μg.ml-1, whereas the leaves and wood extracts of this species showed low toxicity with LC50 = 537 μg.ml-1 and 826 μg.ml-1, respectively.

  19. Implications for toxicity tests with amphipod Gammarus aequicauda: effects of temperature and salinity on life cycle.

    Science.gov (United States)

    Prato, E; Biandolino, F; Scardicchio, C

    2008-12-01

    This study explored the effect of temperature and salinity on the life cycle of Gammarus aequicauda in order to establish temperature and salinity ranges advantageous for chronic toxicity testing. A broad range of salinity-temperature conditions (salinities of 10, 20 and 36 per thousand, and temperatures of 10, 18 and 24 degrees C combined in nine different treatments) significantly influenced various reproductive aspects of G. aequicauda reared in the laboratory, from newly released juveniles to first brood production by mature adults. There was a significant linear regression between the brood size and the body size of the female. The number of juveniles released per female was highest at 10 degrees C and lowest at 24 degrees C. The temperature and salinity variations had a significant effect on the fecundity of G. aequicauda. A high temperature led to a faster individual growth and a quicker sexual development than a lower temperature. A temperature acceptable for chronic toxicity tests can be 18 degrees C, at which an acceleration of the life cycle without a lowering of the amphipod's performance was observed. Regarding salinity, results from this study showed that salinities down to 36 per thousand may also be used in sediment toxicity tests with G. aequicauda, so providing a proper and gradual acclimation.

  20. Evaluation of the hazardous impact of landfill leachates by toxicity and biodegradability tests.

    Science.gov (United States)

    Kalcíková, G; Vávrová, M; Zagorc-Koncan, J; Gotvajn, A Zgajnar

    2011-01-01

    The aim of our research was to assess the ecotoxicity and biodegradability of leachates originating from two parts of a municipal landfill before and after biological treatment in the existing treatment plant. Biotests represent important tools for adequate environmental characterization of landfill leachates and could be helpful in reliable assessment and monitoring of the treatment plant efficiency. For ecotoxicity testing of landfill leachate before and after biological treatment, different organisms were chosen: the bacteria Vibrio fischeri, a mixed culture of activated sludge, duckweed Lemna minor, white mustard Sinapis alba, brine shrimp Artemia salina, and water flea Daphnia magna. For assessment of biodegradability, the method for determination of oxygen demand in a closed respirometer was used. The investigated leachates were heavily polluted, and in some cases, effluent limits were exceeded even after treatment. Results indicated that toxicity tests and physico-chemical parameters determined before and after treatment equivalently assess the efficiency of the existing treatment plant. However, the investigated leachates showed higher toxicity to Daphnia magna and especially to Lemna minor in contrast to Vibrio fischeri and Artemia salina (neither was sensitive to any of the leachates). No leachates were readily biodegradable. Experiments confirmed that the battery of toxicity tests should be applied for more comprehensive assessment of landfill leachate treatment and for reliable assessment of the treated leachate's subsequent environmental impact. It was confirmed that treated leachate, in spite of its better physico-chemical characteristics, still represents a potential environmental risk and thus should not be released into the environment.

  1. Toxicity minimization of pipelines hydrostatic tests fluids, stage I: laboratory essays

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Jorge A.S.; Penna, Monica de O.; Portela, Daniele B.; Christino, Fernando P.; Silva, Joao L.B. da; Geraldo, Lucia M.L. [Petroleo do Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Mota, Vanessa V.C. [Fundacao Gorceix, Ouro Preto, MG (Brazil); Cravo Junior, Walter [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil)

    2009-07-01

    This paper presents the results of the laboratory essays stage of the project for toxicity minimization of pipelines hydrostatic tests fluids. The hydrostatic-hibernation fluid composition most used by PETROBRAS in offshore operations is seawater added with sodium bis sulfite, fluorescein, alquildimetilbenzilamonium chloride, and tetrakis-hydroxymethyl-phosphonium sulfate (THPS). In order to reduce the toxicity of the fluid used in hydrostatic tests, the use of lesser concentrations of THPS was attempted with UV radiation application as a disinfection technique prior to the adding of the fluid's components. The compositions were evaluated in different conditions of temperature use of UV radiation or not and oxygen scavenger adding (presence and absence). The fluids were kept hibernating for 120 days. All the parameters tested after hibernation were compared to fresh from preparation samples (zero time samples). The fluid's characteristics were evaluated by microbiological control and toxicity as well as the THPS residual. Results showed that the UV treatment was more effective in the absence of oxygen scavenger. The temperature acts as a microbial growth control agent, as expected. To large scale operations, a water quality monitoring must be performed previously to any field operations, in order to determinate the best treatment to be used in each case. (author)

  2. In vitro and in vivo toxicity of 5-FdU-alendronate, a novel cytotoxic bone-seeking duplex drug against bone metastasis.

    Science.gov (United States)

    Schott, Sarah; Vallet, Sonia; Tower, Robert J; Noor, Seema; Tiwari, Sanjay; Schem, Christian; Busch, Christian

    2015-08-01

    Bone remains one of the most common anatomic sites for cancer metastases, and the limited therapeutic options aggravate cancer-related morbidity and mortality in multiple malignancies. The covalent conjugation of the amino-bisphosphonate alendronate (ale) with the antimetabolite 5-fluoro-2'-desoxyuridine (5-FdU) results in N(4)-(butyl-(4-hydroxy-4-phosphono)phosphate)-5-fluoro-2'-desoxyuridine (5-FdU-alendronat, 5-FdU-ale), an effective, novel bone-targeting duplex drug directed against skeletal cancer manifestations. In vitro cytotoxicity of ale, 5-FdU or 5-FdU-ale was measured with Alamar Blue and MUH cell viability assays in 14 malignant melanoma, multiple myeloma, bone marrow-derived stromal cell and osteoblast-like cell lines. In vivo toxicity was evaluated using the chicken embryo assay and evaluation of nephrotoxicity and the systemic toxicity in Balb/c nude mice. The effect of 5-FdU-ale on osteoclast was evaluated with Balb/c nude mice in a metastatic breast cancer mouse model. A cell line-specific, dose-related cytotoxicity was observed for 5-FdU-ale in all cancer cell lines tested, which was significantly less toxic than 5-FdU alone when compared to the benign osteoblasts or stromal cells. The embryotoxicity of 5-FdU-ale was significantly less than that of the parental drugs alendronate or 5-FdU. 5-FdU-ale showed no signs of unwanted side effects, weight loss or nephrotoxicity in mice. In a bone metastasis mouse model, 5-FdU-ale reduced the number of tumor-associated osteoclasts. The coupling of an amino-bisphosphonate with an antimetabolite via an N-alkyl-bonding offers a new strategy for the preparation of amino-bisphosphonates conjugates with a cancer cell-specific, efficacious cytotoxic bone-targeting potential along with a reduced systemic toxicity. The innovative duplex drug 5-FdU-ale therefore warrants further clinical investigation.

  3. In vitro toxicity and genotoxicity assessment of disinfection by-products, organic N-chloramines.

    Science.gov (United States)

    Laingam, S; Froscio, S M; Bull, R J; Humpage, A R

    2012-03-01

    Disinfection by-products (DBPs) are of concern to both water industries and health authorities. Although several classes of DBPs have been studied, and there are regulated safe levels in disinfected water for some, a large portion of DBPs are not characterized, and need further investigation. Organic N-chloramines are a group of DBPs, which can be formed during common disinfection processes such as chlorination and chloramination, but little is known in terms of their toxicological significance if consumed in drinking water. Only a few in vitro studies using bacterial assays have reported some genotoxic potential of organic N-chloramines, largely in the context of inflammatory processes in the body rather than exposure through drinking water. In this study, we investigated 16 organic N-chloramines produced by chlorination of model amino acids and amines. It was found that within the drinking water-relevant micromolar concentration range, four compounds were both cytotoxic and genotoxic to mammalian cells. A small reduction of cellular GSH was also observed in the treatment with these four compounds, but not of a magnitude to account for the cytotoxicity and genotoxicity. The results presented in this study demonstrate that some organic N-chloramines, at low concentrations that might be present in disinfected water, can be harmful to mammalian cells.

  4. A cell impedance-based real-time in vitro assay to assess the toxicity of amphotericin B formulations.

    Science.gov (United States)

    Menotti, Jean; Alanio, Alexandre; Sturny-Leclère, Aude; Vitry, Sandrine; Sauvage, Félix; Barratt, Gillian; Bretagne, Stéphane

    2017-11-01

    Aerosolized liposomal amphotericin B (L-AmB) has been investigated as prophylaxis against invasive aspergillosis. However, the clinical results are controversial and some trials suggest that toxicity could be a limitation for wider use. Our aim was to assess the dynamics of cell toxicity induced in a human alveolar epithelial cell line (A549) after exposure to L-AmB (50 to 400μg/ml) or amphotericin B deoxycholate (D-AmB; 50 to 200μg/ml) by monitoring real-time A549 cell viability using an impedance-based technology. Results were expressed as cell index values integrating cell adhesion, proliferation, and survival. In parallel, the gene expression of proinflammatory cytokines was quantified at 6 and 24h after drug addition by real-time RT-PCR on cell lysates. No sustained reduction of cell indexes was observed with L-AmB or empty liposomes, even at 400μg/ml. Only the highest concentration tested of L-AmB (400μg/ml) yielded transient significant 6-fold and 4-fold induction of TNF-α and IL-8 mRNAs, respectively. In contrast, D-AmB induced a decrease in cell indexes and only the 50μg/ml concentration of D-AmB was followed by cell recovery, higher concentrations leading to cell death. Significant 4-fold, 7-fold and 3-fold inductions of TNF-α, IL-8 and IL-33 mRNAs were also observed at 6h with 50μg/ml of D-AmB. In conclusion, continuous cell impedance measurement showed no toxicity on overall cellular behavior although a slight proinflammatory cytokine expression is possible after L-AmB challenge. Real-time kinetics of cell impedance is an interesting tool for initial screening of cell toxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. In vitro toxicity of selected fungicides from the groups of benzimidazoles and demethylation inhibitors to Cladobotryum dendroides and Agaricus bisporus.

    Science.gov (United States)

    Potocnik, Ivana; Vukojević, Jelena; Stajić, Mirjana; Rekanović, Emil; Milijasević, Svetlana; Todorović, Biljana; Stepanović, Milos

    2009-05-01

    Twenty microfungal isolates were collected from diseased fruiting bodies of Agaricus bisporus sampled from Serbian mushroom farms during 2003-2007. Based on morphological characteristics and pathogenicity tests, the isolates were identified as Cladobotryum dendroides. The isolates of C. dendroides and A. bisporusF56 and U3 were tested for sensitivity to several selected fungicides in vitro. C. dendroides isolates were found to be more sensitive to prochloraz manganese and flusilazole + carbendazim than to the other fungicides tested (EC(50) values were 0.09 and 0.11 mg L(- 1), respectively) and weakly resistant to thiophanate-methyl (EC(50) values ranged between 6.53 and 12.09 mg L(- 1)). Selectivity indexes of the tested fungicides on both C. dendroidesand A. bisporusindicated that thiophanate-methyl, cyproconazole + carbendazim and flusilazole + carbendazim had much less selective fungitoxicity than benomyl, carbendazim and prochloraz manganese.

  6. Use of solid-phase adsorbents with the Microtox test for determining the toxicity of hydrophobic chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, G.T. [CSIRO Division of Coal and Energy Technology, Sydney, New South Wales (Australia). Centre for Advanced Analytical Chemistry

    1995-12-31

    The determination of the toxicity of hydrophobic chemicals and to aquatic organisms can be a problem. Often no toxicity is found at concentrations near the solubility of the chemical in water. Solvents are used to increase the solubility of the chemical but the toxicity of the solvent may interfere with the test. Organic extracts of sediments and soil also suffer from the same solubility problems. The Solid-Phase Microtox Test protocol, which involves the incubation of Photobacterium phosphoreum with sediment particles, followed by removal of the particles by filtration, is used for the direct testing of sediment toxicity. The physical and chemical properties of the sediment, however, affect its apparent toxicity to Microtox, giving variable results between polluted and unpolluted sites. Adsorbents, designed for solid-phase extraction, were used as surrogate sediment particles. Toxicants were adsorbed to these materials and were tested for toxicity using the Solid Phase Microtox Test. The advantage of using the absorbent is that they are have a defined surface chemistry, particle size and pore size. Adsorbents containing a variety of functional groups are widely available and can be used for concentrating toxicants from solution by ion exchange, normal phase or reversed phase chromatographic processes. The toxicity of a range of adsorbents to Microtox was determined using the solid-phase protocols. The most toxic absorbent were Florisil and NH{sub 2}(amino) with EC,, values of 2.1 and 5.7 g/L, respectively. Most absorbent had EC{sub 50} values between 50 and 100 g/L and could be used in small amounts for Microtox Tests. Diol and CN(cyanopropyl) absorbent showed no toxicity at concentrations of 100 g/L, the equivalent of one solid-phase cartridge (300 mg) in 3 mL Microtox diluent.

  7. In Vitro activity of Manuka Honey and polyhexamethylene biguanide on filamentous fungi and toxicity to human cell lines.

    Science.gov (United States)

    Yabes, Joseph M; White, Brian K; Murray, Clinton K; Sanchez, Carlos J; Mende, Katrin; Beckius, Miriam L; Zera, Wendy C; Wenke, Joseph C; Akers, Kevin S

    2017-04-01

    Soft-tissue invasive fungal infections are increasingly recognized as significant entities directly contributing to morbidity and mortality. They complicate clinical care, requiring aggressive surgical debridement and systemic antifungal therapy. To evaluate new topical approaches to therapy, we examined the antifungal activity and cytotoxicity of Manuka Honey (MH) and polyhexamethylene biguanide (PHMB). The activities of multiple concentrations of MH (40%, 60%, 80%) and PHMB (0.01%, 0.04%, 0.1%) against 13 clinical mould isolates were evaluated using a time-kill assay between 5 min and 24 h. Concentrations were selected to represent current clinical use. Cell viability was examined in parallel for human epidermal keratinocytes, dermal fibroblasts and osteoblasts, allowing determination of the 50% viability (LD50) concentration. Antifungal activity of both agents correlated more closely with exposure time than concentration. Exophiala and Fusarium growth was completely suppressed at 5 min for all PHMB concentrations, and at 12 and 6 h, respectively, for all MH concentrations. Only Lichtheimia had persistent growth to both agents at 24 h. Viability assays displayed concentration-and time-dependent toxicity for PHMB. For MH, exposure time predicted cytotoxicity only when all cell types were analyzed in aggregate. This study demonstrates that MH and PHMB possess primarily time-dependent antifungal activity, but also exert in vitro toxicity on human cells which may limit clinical use. Further research is needed to determine ideal treatment strategies to optimize antifungal activity against moulds while limiting cytotoxicity against host tissues in vivo. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  8. Sulfide as a confounding factor in toxicity tests with the sea urchin Paracentrotus lividus: comparisons with chemical analysis data.

    Science.gov (United States)

    Losso, Chiara; Arizzi Novelli, Alessandra; Picone, Marco; Volpi Ghirardini, Annamaria; Ghetti, Pier Francesco; Rudello, Danilo; Ugo, Paolo

    2004-02-01

    Sperm cell and embryo toxicity tests with the sea urchin Paracentrotus lividus were performed to assess the toxicity of sulfide, which is considered a confounding factor in toxicity tests. For improved information on the sensitivity of these methods to sulfide, experiments were performed in the same aerobic conditions used for testing environmental samples, with sulfide concentrations being monitored at the same time by cathodic stripping voltammetry. New toxicity data for sulfide expressed as median effective concentration (EC50) and no-observed-effect concentration (NOEC) are reported. The EC50 value for the embryo toxicity test (total sulfide at 0.43 mg/L) was three times lower than for the sperm cell test (total sulfide at 1.20 mg/L), and the NOEC values were similar (on the order of total sulfide at 10(-1) mg/L) for both tests. The decrease in sulfide concentration during the bioassay as a consequence of possible oxidation of sulfide by dissolved oxygen was determined by voltammetric analysis, indicating a half-life of about 50 min in the presence of gametes. To check the influence of sulfide concentrations on toxicity effects in real samples, toxicity (with the sperm cell toxicity test) and chemical analyses also were performed in pore-water samples collected with an in situ sampler in sediments of the Lagoon of Venice (Italy). A highly positive correlation between increased acute toxicity and increased sulfide concentration was found. Examination of data revealed that sulfide is a real confounding factor in toxicity testing in anoxic environmental samples containing concentrations above the sensitivity limit of the method.

  9. InP/ZnS as a safer alternative to CdSe/ZnS core/shell quantum dots: in vitro and in vivo toxicity assessment.

    Science.gov (United States)

    Brunetti, Virgilio; Chibli, Hicham; Fiammengo, Roberto; Galeone, Antonio; Malvindi, Maria Ada; Vecchio, Giuseppe; Cingolani, Roberto; Nadeau, Jay L; Pompa, Pier Paolo

    2013-01-07

    We show that water soluble InP/ZnS core/shell QDs are a safer alternative to CdSe/ZnS QDs for biological applications, by comparing their toxicity in vitro (cell culture) and in vivo (animal model Drosophila). By choosing QDs with comparable physical and chemical properties, we find that cellular uptake and localization are practically identical for these two nanomaterials. Toxicity of CdSe/ZnS QDs appears to be related to the release of poisonous Cd(2+) ions and indeed we show that there is leaching of Cd(2+) ions from the particle core despite the two-layer ZnS shell. Since an almost identical amount of In(III) ions is observed to leach from the core of InP/ZnS QDs, their very low toxicity as revealed in this study hints at a much lower intrinsic toxicity of indium compared to cadmium.

  10. A high throughput passive dosing format for the Fish Embryo Acute Toxicity test

    DEFF Research Database (Denmark)

    Vergauwen, Lucia; Nørgaard Schmidt, Stine; Stinckens, Evelyn

    2015-01-01

    , our objective was to improve exposure conditions in FET tests by evaluating a passive dosing format using silicone O-rings in standard 24-well polystyrene plates. We exposed zebrafish embryos to a series of phenanthrene concentrations until 120 h post fertilization (hpf), and obtained a linear...... was not attributed to impaired swim bladder inflation, but rather to baseline toxicity. We conclude that silicone O-rings (1) produce a linear dilution series of phenanthrene in the 120 hpf FET test, (2) generate and maintain aqueous concentrations for reliable determination of effect concentrations, and allow...

  11. In Vitro Toxicity Evaluation of Silver Nanoparticles on Entamoeba histolytica trophozoite

    Directory of Open Access Journals (Sweden)

    Zahra’a A. Ahmed

    2017-09-01

    Full Text Available The protozoan parasite Entamoeba histolytica is a causative agent of amoebiasis, where it causes millions of cases of dysentery and liver abscess each year. Metronidazole is a drug of choice against amoebiasis. The drug is a choice because of its efficacy and low cost, but at the same time it causes several adverse side effects; therefore, it is important to find effective medications to treat amoebiasis without any complications or any side effects. The aim of this study is to evaluate the effectiveness of different concentrations (50, 75 and 100 µg/ml of silver nanoparticle (AgNPs against trophozoites stages of E. histolytica in vitro. The results showed a significant decrease (p ≤ 0.05 in numbers of trophozoites stages after treated with AgNPs and metronidazole when it was compared with the control. Likewise, a significant difference (p ≤ 0.05 was also observed between AgNPs groups and metronidazole drug, while it did not significantly differ between different concentrations of AgNPs. The mortality rate values of the E. histolytica trophozoites after 48h incubation with AgNPs at a concentration of 50, 75 and 100 μg/ml, and metronidazole were 37.2%, 42.4%, 46.7% and 100%, respectively. The microscopic studies confirmed that AgNPs were effective enough to induce apoptosis. Based on our results, the anti-parasitic activity of AgNPs at different concentrations will reduce the mean number of E. histolytica trophozoites.

  12. In vitro toxicity of nanosized copper particles in PC12 cells induced by oxidative stress

    Science.gov (United States)

    Xu, Pengjuan; Xu, Jing; Liu, Shichang; Ren, Guogang; Yang, Zhuo

    2012-06-01

    Recent evidence suggests that some nanomaterials, which are widely used in many fields, have health effects. In order to investigate the cytotoxicity induced by nanosized copper particles (nano-Cu), PC12 cells, which were widely used as an in vitro model for the neuron research, were treated with different concentrations (0, 1, 10, 30, and 100 μg/mL) of nano-Cu. The cell viability was determined by measurement of the reduction product of 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT). The oxidative stress induced by nano-Cu and its possible mechanism were studied in relation to the generation of reactive oxygen species (ROS) and the cellular activity of superoxide dismutase (SOD). Results showed that incubation of PC12 cells with increasing concentrations of nano-Cu induced a decrease of cell viability in a concentration- and time-dependent manner. In addition, flow cytometry assay using Annexin V-FITC/PI staining was used to investigate the mode of nano-Cu-induced cell death and quantified the percentage of apoptotic cells. Results showed that nano-Cu induced the significant apoptosis in PC12 cells. Meanwhile, intracellular accumulation of ROS was increased with the increased concentrations of nano-Cu and it was associated with decreased SOD activity, which was probably due to protect effects against the oxidative stress in PC12 cells. Results suggested that both excessive intracellular ROS and decreased SOD contributed to nano-Cu-induced cytotoxicity. In other words, the increasing of oxidative stress was a key mechanism in PC12 apoptosis induced by nano-Cu.

  13. Single species aquatic toxicity testing for environmental regulation of chemicals. Proposal for a flexible testing approach

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, P.; Roghair, C.; Tyle, H.

    1995-12-31

    In a co-operation between Denmark and The Netherlands, a Detailed Review Paper on Aquatic Testing Methods for Pesticides and Industrial Chemicals has been elaborated for the consideration of the National Coordinators of the OECD Test Guideline Programme. The objective of the review is to identify the need for revision of existing OECD Test Guidelines and also to identify the need for elaboration of new guidelines. The background for the recommendations made is (1) a comprehensive review of more than 600 pelagic and benthic testing methods collected from national standardization organizations and from the scientific literature, (2) an evaluation of the methods based on a set of formalized evaluation criteria, (3) an identification of the present needs in national and international aquatic effects assessment schemes and (4) a proposed framework for future assessment of chemicals in specific types of aquatic environments. It is foreseen that future assessments (which go beyond the initial generic assessment) may be directed toward specific types of aquatic environments. The proposal for new testing methods has therefore been framed into five testing scenarios. Four testing scenarios for the benthic and pelagic compartments, respectively: cold freshwater environment, warm freshwater environment, cold marine environment and warm marine environment and a testing scenario for assessment of biological waste water treatment. The rational for the elaboration of single species testing scenarios will especially be addressed.

  14. Structure-activity relationships for chloro- and nitrophenol toxicity in the pollen tube growth test

    Energy Technology Data Exchange (ETDEWEB)

    Schueuermann, G. [UFZ Centre for Environmental Research, Leipzig (Germany). Dept. of Chemical Ecotoxicology; Somashekar, R.K. [Bangalore Univ. (India). Dept. of Botany; Kristen, U. [Univ. Hamburg (Germany). Inst. fuer Allgemeine Botanik

    1996-10-01

    Acute toxicity of 10 chlorophenols and 10 nitrophenols with identical substitution patterns is analyzed with the pollen tube growth (PTG) test. Concentration values of 50% growth inhibition (IC50) between 0.1 and 300 mg/L indicate that the absolute sensitivity of this alternative biotest is comparable to conventional aquatic test systems. Analysis of quantitative structure-activity relationships using lipophilicity (log K{sub ow}), acidity (pK{sub a}), and quantum chemical parameters to model intrinsic acidity, solvation interactions, and nucleophilicity reveals substantial differences between the intraseries trends of log IC50. With chlorophenols, a narcotic-type relationship is derived, which, however, shows marked differences in slope and intercept when compared to reference regression equations for polar narcosis. Regression analysis of nitrophenol toxicity suggests interpretation in terms of two modes of action: oxidative uncoupling activity is associated with a pK{sub a} window from 3.8 to 8.5, and more acidic congeners with diortho-substitution show a transition from uncoupling to a narcotic mode of action with decreasing pK{sub a} and log K{sub ow}. Model calculations for phenol nucleophilicity suggest that differences in the phenol readiness for glucuronic acid conjugation as a major phase-II detoxication pathway have no direct influence on acute PTG toxicity of the compounds.

  15. Comparative rice seed toxicity tests using filter paper, growth pouch-tm, and seed tray methods

    Science.gov (United States)

    Wang, W.

    1993-01-01

    Paper substrate, especially circular filter paper placed inside a Petri dish, has long been used for the plant seed toxicity test (PSTT). Although this method is simple and inexpensive, recent evidence indicates that it gives results that are significantly different from those obtained using a method that does not involve paper, especially when testing metal cations. The study compared PSTT using three methods: filter paper, Growth Pouch-TM, and seed tray. The Growth Pouch-TM is a commercially available device. The seed tray is a newly designed plastic receptacle placed inside a Petri dish. The results of the Growth Pouch-TM method showed no toxic effects on rice for Ag up to 40 mg L-1 and Cd up to 20 mg L-1. Using the seed tray method, IC50 (50% inhibitory effect concentration) values were 0.55 and 1.4 mg L-1 for Ag and Cd, respectively. Although results of filter paper and seed tray methods were nearly identical for NaF, Cr(VI), and phenol, the toxicities of cations Ag and Cd were reduced by using the filter paper method; IC50 values were 22 and 18 mg L-1, respectively. The results clearly indicate that paper substrate is not advisable for PSTT.

  16. [In vitro cytotoxicity test of medical ultrasonic couplant].

    Science.gov (United States)

    Gao, Jingxian; Wang, Shasha; Jin, Meng; Yan, Xiaoli

    2013-05-01

    The cytotoxicity of medical ultrasonic couplant was tested by MTT assay and agar overlay test. By MTT assay, when the inoculum density was high, the cytotoxicity level was low, or vice versa. The cytotoxicity grade tested by agar overlay was not accord to MTT assay's too. MTT assay is suitable to test the cytotoxicity of medical ultrasonic couplant because it is quantitative and more sensitive, however, the experimental condition and the preparative method of extraction should be determined.

  17. In Vitro Toxicity of Naturally Occurring Silica Nanoparticles in C1 Coal 
in Bronchial Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Guangjian LI

    2012-10-01

    Full Text Available Background and objective China’s Xuan Wei County in Yunnan Province have the world’s highest incidence of lung cancer in nonsmoking women-20 times higher than the rest of China. Previous studies showed, this high lung cancer incidence may be associated with the silica particles embedded in the production combustion from the C1 coal. The aim of this study is to separate the silica particles from production combustion from the C1 bituminous coal in Xuan Wei County of Yunnan Province, and study in vitro toxicity of naturally occurring silica particles on BEAS-2B. Methods ①Separating the silica particles from combustion products of C1 bituminous coal by physical method, observing the morphology by Scanning Electron Microscope, analysis elements by SEM-EDX, observed the single particle morphology by Transmission Electron Microscope, analyed its particle size distribution by Laser particle size analyzer, the surface area of silica particles were determined by BET nitrogen adsorption analysis; ②Cell viability of the experimental group (silica; naturally occurring, control group (silica; industrial produced and crystalline silica was detected by assay used the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT method, and the reactive oxygen species (ROS, lactate dehydrogenase (LDH were determined after 24 h-72 h exposed to these particles. Results ①The physical method can separate silica particles from production combustion from the C1 bituminous coal, which have different size, and from 30 nm to 120 nm particles accounted for 86.8%, different morphology, irregular surface area and containing trace of aluminum, calcium and iron and other elements; ②Under the same concentration, the experiment group have higher toxicity on BEAS-2B than control groups. Conclusion ①Physical method can separate silica particles from production combustion from the C1 bituminous coal and not change the original morphology and containing trace;

  18. Toxicity testing of dispersed oil requires adherence to standardized protocols to assess potential real world effects.

    Science.gov (United States)

    Coelho, Gina; Clark, James; Aurand, Don

    2013-06-01

    Recently, several researchers have attempted to address Deepwater Horizon incident environmental fate and effects issues using laboratory testing and extrapolation procedures that are not fully reliable measures for environmental assessments. The 2013 Rico-Martínez et al. publication utilized laboratory testing approaches that severely limit our ability to reliably extrapolate such results to meaningful real-world assessments. The authors did not adopt key methodological elements of oil and dispersed oil toxicity standards. Further, they drew real-world conclusions from static exposure tests without reporting actual exposure concentrations. Without this information, it is not possible to compare their results to other research or real spill events that measured and reported exposure concentrations. The 1990s' Chemical Response to Oil Spills: Ecological Effects Research Forum program was established to standardize and conduct exposure characterization in oil and dispersed oil aquatic toxicity testing (Aurand and Coelho, 2005). This commentary raises awareness regarding the necessity of standardized test protocols. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Use of sublethal endpoints in sediment toxicity tests with the amphipod Hyalella azteca

    Science.gov (United States)

    Ingersoll, Chris G.; Brunson, Eric L.; Dwyer, F. James; Hardesty, Douglas K.; Kemble, Nile E.

    1998-01-01

    Short-term sediment toxicity tests that only measure effects on survival can be used to identify high levels of contamination but may not be able to identify marginally contaminated sediments. The objective of the present study was to develop a method for determining the potential sublethal effects of contaminants associated with sediment on the amphipod Hyalella azteca (e.g., reproduction). Exposures to sediment were started with 7- to 8-d-old amphipods. On day 28, amphipods were isolated from the sediment and placed in water-only chambers where reproduction was measured on day 35 and 42. Typically, amphipods were first in amplexus at about day 21 to 28 with release of the first brood between day 28 to 42. Endpoints measured included survival (day 28, 35, and 42), growth (as length and weight on day 28 and 42), and reproduction (number of young/female produced from day 28 to 42). This method was used to evaluate a formulated sediment and field-collected sediments with low to moderate concentrations of contaminants. Survival of amphipods in these sediments was typically >85% after the 28-d sediment exposures and the 14-d holding period in water to measure reproduction. Reproduction was more variable than growth; hence, more replicates might be needed to establish statistical differences among treatments. Previous studies have demonstrated that growth of H. azteca in sediment tests often provides unique information that can be used to discriminate toxic effects of exposure to contaminants. Either length or weight can be measured in sediment tests with H. azteca. However, additional statistical options are available if length is measured on individual amphipods, such as nested analysis of variance that can account for variance in length within replicates. Ongoing water-only studies testing select contaminants will provide additional data on the relative sensitivity and variability of sublethal endpoints in toxicity tests with H. azteca.

  20. [Subchronic toxicity test of genetically modified rice with double antisense starch-branching enzyme gene].

    Science.gov (United States)

    Li, Min; Piao, Jianhua; Yang, Xiaoguang

    2010-07-01

    To observe the sub-chronic toxic effects of the genetically modified rice with double antisense SBE gene. Based on gender and weight, weanling Wistar rats were randomly sorted into five groups: non-genetically modified rice group (group A), genetically modified rice group (group B), half genetically modified rice group (group C), quarter genetically modified rice group (group D) and AIN-93G normal diet group (group E). Indicators were the followings: body weight, food consumption, blood routine, blood biochemical test, organ weight, bone density and pathological examination of organs. At the middle of the experiment, the percentage of monocyte of female group B was less than that of group E (P 0.05), and no notable abnormity in the pathological examination of main organs (P > 0.05). There were no enough evidence to confirm the sub-chronic toxicity of genetically modified rice on rats.

  1. Acute toxicity of copper oxide nanoparticles to Daphnia magna under different test conditions

    DEFF Research Database (Denmark)

    Thit, Amalie; Huggins, Krista; Selck, Henriette

    2017-01-01

    suspensions changed in a way similar to what is known for dissolved Cu: first in ISO standard test conditions (pH 7.8), second with slight acidity (pH 6.5), third in the presence of citric acid, and fourth in the presence of humic acid. For all four exposure conditions, the toxicity of Cu employed...... in the three forms followed the same sequence, i.e., CuSO4 > monodispersed 6 nm CuO ≫ poly-dispersed CuO. The toxicity of all Cu forms decreased from pH 6.5, ≫ pH 7.8, > pH 7.8 + citric acid, to ≫ pH 7.8 + humic acid. This pattern is in agreem