Inhibition of galactosamine cytotoxicity in an in vivo/in vitro hepatocellular toxicity model

International Nuclear Information System (INIS)

MacDonald, J.R.; Thayer, K.J.; White, C.

1987-01-01

A combined in vivo/in vitro model of galactosamine hepatotoxicity was employed to test whether previously reported cytoprotective actions of cystamine administration on galactosamine-induced hepatic injury in vivo could be attributed to a direct action of cystamine on toxicant-challenged hepatocytes. In this model, male Sprague-Dawley rats received a 400 mg/kg galactosamine challenge via intraperitoneal injection 1 hr prior to portal vein cannulation for hepatocyte isolation. Isolated cells are established in monolayer culture and galactosamine-induced cellular injury is then expressed over the ensuing 24-48 hr in culture. Consistent with the biochemical basis of galactosamine-induced hepatocellular injury in vivo, cytotoxicity could be prevented by in vitro uridine treatments within 3 hr of the in vivo galactosamine challenge, but not when added 12 hr later. Cystamine, in contrast, exhibited a cytoprotective effect even when added to cultures 12 hr after the in vivo toxicant challenge. Post-toxicant cytoprotection by cystamine in vitro was concentration dependent and did not produce an alteration of hepatocyte nonprotein sulfhydryl content. Post-toxicant cytoprotection by uridine and cystamine in this in vivo/in vitro model of toxicity were fully consistent with in vivo protection from galactosamine-induced necrosis by these agents. This model eliminates potential extrahepatic mechanisms for cystamine's hepatoprotective effect and demonstrates a direct cytoprotective action on galactosamine-challenged hepatocytes

Comparative In Vitro Biological Toxicity of Four Kinds of Air Pollution Particles.

Science.gov (United States)

Shin, Han-Jae; Cho, Hyun Gi; Park, Chang Kyun; Park, Ki Hong; Lim, Heung Bin

2017-10-01

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

Impact of bioavailability on the correlation between in vitro cytotoxic and in vivo acute fish toxic concentrations of chemicals

International Nuclear Information System (INIS)

Guelden, Michael; Seibert, Hasso

2005-01-01

The lower sensitivity of in vitro cytotoxicity assays currently restricts their use as alternative to the fish acute toxicity assays for hazard assessment of chemicals in the aquatic environment. In vitro cytotoxic potencies mostly refer to nominal concentrations. The main objective of the present study was to investigate, whether a reduced availability of chemicals in vitro can account for the lower sensitivity of in vitro toxicity test systems. For this purpose, the bioavailable free fractions of the nominal cytotoxic concentrations (EC 50 ) of chemicals determined with a cytotoxicity test system using Balb/c 3T3 cells and the corresponding free cytotoxic concentrations (ECu 50 ) were calculated. The algorithm applied is based on a previously developed simple equilibrium distribution model for chemicals in cell cultures with serum-supplemented culture media. This model considers the distribution of chemicals between water, lipids and serum albumin. The algorithm requires the relative lipid volume of the test system, the octanol-water partition coefficient (K ow ) and the in vitro albumin-bound fraction of the chemicals. The latter was determined from EC 50 -measurements in the presence of different albumin concentrations with the Balb/c 3T3 test system. Organic chemicals covering a wide range of cytotoxic potency (EC 50 : 0.16-527000 μM) and lipophilicity (log K ow : -5.0-6.96) were selected, for which fish acute toxicity data (LC 50 -values) from at least one of the three fish species, medaka, rainbow trout and fathead minnow, respectively, were available. The availability of several chemicals was shown to be extensively reduced either by partitioning into lipids or by serum albumin binding, or due to both mechanisms. Reduction of bioavailability became more important with increasing cytotoxic potency. The sensitivity of the Balb/c 3T3 cytotoxicity assay and the correspondence between in vivo and in vitro toxic potencies were increased when the free cytotoxic

In vitro toxicity of infusion sets depends on their composition, storage time and storage conditions.

Science.gov (United States)

Kozlovskaya, Luba; Popilski, Hen; Gorenbein, Pavel; Stepensky, David

2015-07-15

Disposable medical devices release toxic leachables during their clinical use. Specifically, the individual parts of the infusion sets (the drip chamber, tube, flashball and injection site) are composed of numerous chemical compounds that can reach the patients' systemic circulation and induce local and systemic toxic effects. We aimed to reveal the relative in vitro toxicity of infusion sets from the leading vendors that are used in Israel, and to determine its dependence on their design and storage time/conditions. We found that leachates of the rubber parts were more toxic than those of the other parts of the infusion sets. The measured toxicity was affected by the experimental settings: the cells, medium composition, exposure duration, and the type of assay applied for toxicity assessment. We recommend to use the capillary endothelium cells for in vitro toxicity testing of the infusion sets, and refrain from the use of the MTT test which is insufficiently reliable, and can lead to artefacts and incorrect conclusions. Further investigation is needed to identify the toxic leachables from the individual parts of the infusion sets, and to reveal the risk of their toxicity during the clinical use of the infusion sets. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

Test systems to identify reproductive toxicants.

Science.gov (United States)

Riecke, K; Stahlmann, R

2000-09-01

Experience with drugs and other xenobiotics indicates that both animal testing and epidemiological studies are necessary to provide adequate data for an estimation of risks that might be associated with exposure to a chemical substance. In this review, the pros and cons of test systems for reproductive toxicity are discussed. Usually, several studies are performed to cover the different phases of the reproductive cycle. In the preclinical development of drugs, the three so-called 'segment testing protocols' have been used for several decades now. More recently, new testing concepts have been accepted internationally which include more flexibility in implementation. Several examples of compounds with the potential for reproductive toxicity are presented in more detail in a discussion of some pitfalls of the tests for fertility (phthalates and fluoroquinolones), teratogenicity (acyclovir and protease inhibitors) and postnatal developmental toxicity (fluoroquinolones). In addition, important aspects of kinetics and metabolism as a prerequisite for a rational interpretation of results from toxicological studies are briefly discussed. In vitro assays are useful for supplementing the routinely used in vivo approaches or for studying an expected or defined effect, but they are not suitable for revealing an unknown effect of a chemical on the complex reproductive process.

Building predictive in vitro pulmonary toxicity assays using high-throughput imaging and artificial intelligence.

Science.gov (United States)

Lee, Jia-Ying Joey; Miller, James Alastair; Basu, Sreetama; Kee, Ting-Zhen Vanessa; Loo, Lit-Hsin

2018-06-01

Human lungs are susceptible to the toxicity induced by soluble xenobiotics. However, the direct cellular effects of many pulmonotoxic chemicals are not always clear, and thus, a general in vitro assay for testing pulmonotoxicity applicable to a wide variety of chemicals is not currently available. Here, we report a study that uses high-throughput imaging and artificial intelligence to build an in vitro pulmonotoxicity assay by automatically comparing and selecting human lung-cell lines and their associated quantitative phenotypic features most predictive of in vivo pulmonotoxicity. This approach is called "High-throughput In vitro Phenotypic Profiling for Toxicity Prediction" (HIPPTox). We found that the resulting assay based on two phenotypic features of a human bronchial epithelial cell line, BEAS-2B, can accurately classify 33 reference chemicals with human pulmonotoxicity information (88.8% balance accuracy, 84.6% sensitivity, and 93.0% specificity). In comparison, the predictivity of a standard cell-viability assay on the same set of chemicals is much lower (77.1% balanced accuracy, 84.6% sensitivity, and 69.5% specificity). We also used the assay to evaluate 17 additional test chemicals with unknown/unclear human pulmonotoxicity, and experimentally confirmed that many of the pulmonotoxic reference and predicted-positive test chemicals induce DNA strand breaks and/or activation of the DNA-damage response (DDR) pathway. Therefore, HIPPTox helps us to uncover these common modes-of-action of pulmonotoxic chemicals. HIPPTox may also be applied to other cell types or models, and accelerate the development of predictive in vitro assays for other cell-type- or organ-specific toxicities.

Animal Testing for Acute Inhalation Toxicity: A Thing of the Past?

DEFF Research Database (Denmark)

Da Silva, Emilie; Sørli, Jorid Birkelund

2018-01-01

According to REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals), testing for acute inhalation toxicity is required for chemicals manufactured or imported at tonnages ≥ 10 tons per year. Three OECD test guidelines for acute inhalation toxicity in vivo are adopted (TG 403......, TG 436, and TG 433). Since animal testing is ethically, scientifically and economically questionable, adoption of alternative methods by the European Union and the OECD is needed. An in vitro system based on the study of lung surfactant function is introduced....

In vitro toxicity analysis of nanoscale aluminum: Particle size and shape effects

Science.gov (United States)

Palazuelos Jorganes, Maria

2007-12-01

Nanostructured materials promise to revolutionize many key areas of science and technology. As our ability to manipulate matter at the nanoscale increases, there is a need to assess the effects of these materials on human health and the environment. Materials at the nanoscale are interesting and useful because they possess properties that are different from the equivalent bulk or molecular scale. These same properties can make toxicological profiles very different from those of the same materials on a different scale. There is a rising consensus that toxicity analysis of nanomaterials should start from a thorough physicochemical characterization of the materials under investigation in order to be able to establish a proper correlation between the nanoparticles characteristics and their effects and behavior in physiological environments. This research is a clear example of the necessity of comprehensive studies when investigating the toxicity of nanomaterials. Aluminum nanoparticles are being extensively used for their very unique energetic properties. These materials offer a very promising market that is fostering many startup companies which are expected to consolidate on strong technological positions. Aluminum is generally recognized as a non-toxic material to humans and it is widely used for applications which imply direct human contact. The effect of aluminum nanoparticles in human health is still an unknown. My research consisted of an in vitro toxicity screening of aluminum materials from nano to micron size, including spherical irregularly shaped particles. Several issues relating to size, shape, detection and characterization of nanoparticles in the different environments relevant to in vitro toxicity analysis were addressed and suitable protocols were developed. Lung human epithelial cells were exposed to different concentrations of these materials and the effects were analyzed by means of various toxicity tests. Some of the materials investigated caused

In Vitro Screening of Environmental Chemicals for Targeted Testing Prioritization: The ToxCast Project

OpenAIRE

Judson, Richard S.; Houck, Keith A.; Kavlock, Robert J.; Knudsen, Thomas B.; Martin, Matthew T.; Mortensen, Holly M.; Reif, David M.; Rotroff, Daniel M.; Shah, Imran; Richard, Ann M.; Dix, David J.

2009-01-01

Background Chemical toxicity testing is being transformed by advances in biology and computer modeling, concerns over animal use, and the thousands of environmental chemicals lacking toxicity data. The U.S. Environmental Protection Agency?s ToxCast program aims to address these concerns by screening and prioritizing chemicals for potential human toxicity using in vitro assays and in silico approaches. Objectives This project aims to evaluate the use of in vitro assays for understanding the ty...

Injectible candidate sealants for fetal membrane repair: Bonding and toxicity in vitro

Science.gov (United States)

Bilic, Grozdana; Brubaker, Carrie; Messersmith, Phillip B.; Mallik, Ajit S.; Quinn, Thomas M.; Haller, Claudia; Done, Elisa; Gucciardo, Leonardo; Zeisberger, Steffen M.; Zimmermann, Roland; Deprest, Jan; Zisch, Andreas H.

2010-01-01

Objective This study was undertaken to test injectible surgical sealants that are biocompatible with fetal membranes, eventually for closure of iatrogenic membrane defects. Study Design Dermabond, Histoacryl, Tissucol fibrin glue, and three types of in situ forming poly(ethylene glycol)-based polymer hydrogels were tested for acute toxicity upon direct contact with fetal membranes for 24h. For determination of elution toxicity, extracts of sealants were incubated on amnion cell cultures for 72h. Bonding and toxicity was assessed through morphological and/or biochemical analysis. Results Extracts of all adhesives were non-toxic for cultured cells. However, only Tissucol and one type of poly(ethylene glycol)-based hydrogel, mussel-mimetic tissue adhesive, showed efficient, non-disruptive, non-toxic bonding to fetal membranes. Mussel-mimetic tissue adhesive applied over membrane defects created with a 3.5 mm trocar accomplished leak-proof closure that withstood membrane stretch in an in vitro model. Conclusion A synthetic hydrogel-type tissue adhesive emerged as potential sealing modality for iatrogenic membrane defects that merits further evaluation in vivo. PMID:20096254

Toward toxicity testing of nanomaterials in the 21st century: a paradigm for moving forward.

Science.gov (United States)

Lai, David Y

2012-01-01

A challenge-facing hazard identification and safety evaluation of engineered nanomaterials being introduced to market is the diversity and complexity of the types of materials with varying physicochemical properties, many of which can affect their toxicity by different mechanisms. In general, in vitro test systems have limited usefulness for hazard identification of nanoparticles due to various issues. Meanwhile, conducting chronic toxicity/carcinogenicity studies in rodents for every new nanomaterial introduced into the commerce is impractical if not impossible. New toxicity testing systems which rely on predictive, high-throughput technologies may be the ultimate goal of evaluating the potential hazard of nanomaterials. However, at present, this approach alone is unlikely to succeed in evaluating the toxicity of the wide array of nanomaterials and requires validation from in vivo studies. This article proposes a paradigm for toxicity testing and elucidation of the molecular mechanisms of reference materials for specific nanomaterial classes/subclasses using short-term in vivo animal studies in conjunction with high-throughput screenings and mechanism-based short-term in vitro assays. The hazard potential of a particular nanomaterial can be evaluated by conducting only in vitro high-throughput assays and mechanistic studies and comparing the data with those of the reference materials in the specific class/subclass-an approach in line with the vision for 'Toxicity Testing in the 21st Century' of chemicals. With well-designed experiments, testing nanomaterials of varying/selected physicochemical parameters may be able to identify the physicochemical parameters contributing to toxicity. The data so derived could be used for the development of computer model systems to predict the hazard potential of specific nanoparticles based on property-activity relationships. Copyright © 2011 John Wiley & Sons, Inc.

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.

In vitro screening for population variability in toxicity of pesticide-containing mixtures

Science.gov (United States)

Abdo, Nour; Wetmore, Barbara A.; Chappell, Grace A.; Shea, Damian; Wright, Fred A.; Rusyna, Ivan

2016-01-01

Population-based human in vitro models offer exceptional opportunities for evaluating the potential hazard and mode of action of chemicals, as well as variability in responses to toxic insults among individuals. This study was designed to test the hypothesis that comparative population genomics with efficient in vitro experimental design can be used for evaluation of the potential for hazard, mode of action, and the extent of population variability in responses to chemical mixtures. We selected 146 lymphoblast cell lines from 4 ancestrally and geographically diverse human populations based on the availability of genome sequence and basal RNA-seq data. Cells were exposed to two pesticide mixtures – an environmental surface water sample comprised primarily of organochlorine pesticides and a laboratory-prepared mixture of 36 currently used pesticides – in concentration response and evaluated for cytotoxicity. On average, the two mixtures exhibited a similar range of in vitro cytotoxicity and showed considerable inter-individual variability across screened cell lines. However, when in vitroto-in vivo extrapolation (IVIVE) coupled with reverse dosimetry was employed to convert the in vitro cytotoxic concentrations to oral equivalent doses and compared to the upper bound of predicted human exposure, we found that a nominally more cytotoxic chlorinated pesticide mixture is expected to have greater margin of safety (more than 5 orders of magnitude) as compared to the current use pesticide mixture (less than 2 orders of magnitude) due primarily to differences in exposure predictions. Multivariate genome-wide association mapping revealed an association between the toxicity of current use pesticide mixture and a polymorphism in rs1947825 in C17orf54. We conclude that a combination of in vitro human population-based cytotoxicity screening followed by dosimetric adjustment and comparative population genomics analyses enables quantitative evaluation of human health hazard

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

In vitro screening of environmental chemicals for targeted testing prioritization: the ToxCast project.

Science.gov (United States)

Judson, Richard S; Houck, Keith A; Kavlock, Robert J; Knudsen, Thomas B; Martin, Matthew T; Mortensen, Holly M; Reif, David M; Rotroff, Daniel M; Shah, Imran; Richard, Ann M; Dix, David J

2010-04-01

Chemical toxicity testing is being transformed by advances in biology and computer modeling, concerns over animal use, and the thousands of environmental chemicals lacking toxicity data. The U.S. Environmental Protection Agency's ToxCast program aims to address these concerns by screening and prioritizing chemicals for potential human toxicity using in vitro assays and in silico approaches. This project aims to evaluate the use of in vitro assays for understanding the types of molecular and pathway perturbations caused by environmental chemicals and to build initial prioritization models of in vivo toxicity. We tested 309 mostly pesticide active chemicals in 467 assays across nine technologies, including high-throughput cell-free assays and cell-based assays, in multiple human primary cells and cell lines plus rat primary hepatocytes. Both individual and composite scores for effects on genes and pathways were analyzed. Chemicals displayed a broad spectrum of activity at the molecular and pathway levels. We saw many expected interactions, including endocrine and xenobiotic metabolism enzyme activity. Chemicals ranged in promiscuity across pathways, from no activity to affecting dozens of pathways. We found a statistically significant inverse association between the number of pathways perturbed by a chemical at low in vitro concentrations and the lowest in vivo dose at which a chemical causes toxicity. We also found associations between a small set of in vitro assays and rodent liver lesion formation. This approach promises to provide meaningful data on the thousands of untested environmental chemicals and to guide targeted testing of environmental contaminants.

Transgenic Mouse Models Transferred into the Test Tube: New Perspectives for Developmental Toxicity Testing In Vitro?

Science.gov (United States)

Kugler, Josephine; Luch, Andreas; Oelgeschläger, Michael

2016-10-01

Despite our increasing understanding of molecular mechanisms controlling embryogenesis, the identification and characterization of teratogenic substances still heavily relies on animal testing. Embryonic development depends on cell-autonomous and non-autonomous processes including spatiotemporally regulated extracellular signaling activities. These have been elucidated in transgenic mouse models harboring easily detectable reporter genes under the control of evolutionarily conserved signaling cascades. We propose combining these transgenic mouse models and cells derived thereof with existing alternative toxicological testing strategies. This would enable the plausibility of in vitro data to be verified in light of in vivo data and, ultimately, facilitate regulatory acceptance of in vitro test methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

Digital holographic microscopy for toxicity testing and cell culture quality control

Science.gov (United States)

Kemper, Björn

2018-02-01

For the example of digital holographic microscopy (DHM), it is illustrated how label-free biophysical parameter sets can be extracted from quantitative phase images of adherent and suspended cells, and how the retrieved data can be applied for in-vitro toxicity testing and cell culture quality assessment. This includes results from the quantification of the reactions of cells to toxic substances as well as data from sophisticated monitoring of cell alterations that are related to changes of cell culture conditions.

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...... of the paper products were extracted with either 99% ethanol or water. Potential migrants in the extracts were identified and semiquantified by GC-1R-MS or GC-HRMS. In parallel to the chemical analyses, a battery of four different in vitro toxicity tests with different endpoints were applied to the same...... was less cytotoxic than the extracts prepared from paper made from recycled fibres, and extracts prepared from C was the most cytotoxic. None of the extracts showed mutagenic activity No conclusion about the oestrogenic activity could be made, because all extracts were cytotoxic to the test organism (yeast...

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

International Nuclear Information System (INIS)

Doherty, Kimberly R.; Wappel, Robert L.; Talbert, Dominique R.; Trusk, Patricia B.; Moran, Diarmuid M.; Kramer, James W.; Brown, Arthur M.; Shell, Scott A.; Bacus, Sarah

2013-01-01

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

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.

Assessing reproductive toxicity of two environmental toxicants with a novel in vitro human spermatogenic model

Directory of Open Access Journals (Sweden)

Charles A. Easley, IV

2015-05-01

Full Text Available Environmental influences and insults by reproductive toxicant exposure can lead to impaired spermatogenesis or infertility. Understanding how toxicants disrupt spermatogenesis is critical for determining how environmental factors contribute to impaired fertility. While current animal models are available, understanding of the reproductive toxic effects on human fertility requires a more robust model system. We recently demonstrated that human pluripotent stem cells can differentiate into spermatogonial stem cells/spermatogonia, primary and secondary spermatocytes, and haploid spermatids; a model that mimics many aspects of human spermatogenesis. Here, using this model system, we examine the effects of 2-bromopropane (2-BP and 1,2,dibromo-3-chloropropane (DBCP on in vitro human spermatogenesis. 2-BP and DBCP are non-endocrine disrupting toxicants that are known to impact male fertility. We show that acute treatment with either 2-BP or DBCP induces a reduction in germ cell viability through apoptosis. 2-BP and DBCP affect viability of different cell populations as 2-BP primarily reduces spermatocyte viability, whereas DBCP exerts a much greater effect on spermatogonia. Acute treatment with 2-BP or DBCP also reduces the percentage of haploid spermatids. Both 2-BP and DBCP induce reactive oxygen species (ROS formation leading to an oxidized cellular environment. Taken together, these results suggest that acute exposure with 2-BP or DBCP causes human germ cell death in vitro by inducing ROS formation. This system represents a unique platform for assessing human reproductive toxicity potential of various environmental toxicants in a rapid, efficient, and unbiased format.

Comparative analysis of the toxic effects of natural toxins and harmful substances produced by conventional processing methods or by irradiation and of toxicity tests

International Nuclear Information System (INIS)

Dahlhelm, H.; Arndt, K.; Groeger, G.; Schreiber, G.A.; Boegl, K.W.

1994-01-01

In this review, tasks and methods of food toxicology as well as the application of the different toxicity tests for the risk assessment of food ingredients are described. Particular reference is made to short-term genotoxicity tests. Enzymatic digestion and extraction methods for complex foodstuffs which are used in the toxicological testing of foods in in vitro systems are described. Radiolytic products which result from irradiation of foods or components of foodstuffs and corresponding results of toxicity testing are reviewed. Foodstuffs irradiated with doses of up to 10 kGy are regarded as toxicologically safe. A survey of the toxicologically tested irradiated foodstuffs as well as the applied maximum doses are given in tables at the end of chapter 8. Among the great number of toxicological studies of irradiated foods those are especially mentioned which have given rise to discussions on the health risks involved. In addition, the difficulties associated with the testing of toxicity of irradiated foodstuffs in feeding experiments are discussed. Short-term tests used to establish the benotoxicity of irradiated foods and essential results of toxicological testing are also presented in tables. An overview is given of the occurrence, frequency and health risks of natural toxins in foods and harmful substances produced by conventional methods of cooking and preservation, in order to enable a comparison with the health risks of irradiated foods. The relevance of animal experiments and in vitro investigations for the prediction of toxic effects of harmful substances of foodstuffs in man is discussed in the final chapter. (VHE) [de

In Vitro Toxicity of Aluminum Nanoparticles in Human Keratinocytes

National Research Council Canada - National Science Library

McCormack-Brown, Stephanie

2008-01-01

.... There is no published data on AL NP toxicity effects on human skin. This research used in vitro techniques to determine the cytotoxicity of AL NPs, sized 50, 80, and 120 nm, on human keratinocytes...

Case Study Approaches for Implementing the 2007 NRC Report “Toxicity Testing in the 21st Century: A Vision and A Strategy”

Science.gov (United States)

Andersen, Melvin E.; Clewell, Harvey J.; Carmichael, Paul L.; Boekelheide, Kim

2013-01-01

The 2007 report “Toxicity Testing in the 21st Century: A Vision and A Strategy” argued for a change in toxicity testing for environmental agents and discussed federal funding mechanisms that could be used to support this transformation within the USA. The new approach would test for in vitro perturbations of toxicity pathways using human cells with high throughput testing platforms. The NRC report proposed a deliberate timeline, spanning about 20 years, to implement a wholesale replacement of current in-life toxicity test approaches focused on apical responses with in vitro assays. One approach to accelerating implementation is to focus on well-studied prototype compounds with known toxicity pathway targets. Through a series of carefully executed case studies with four or five pathway prototypes, the various steps required for implementation of an in vitro toxicity pathway approach to risk assessment could be developed and refined. In this article, we discuss alternative approaches for implementation and also outline advantages of a case study approach and the manner in which the cases studies could be pursued using current methodologies. A case study approach would be complementary to recently proposed efforts to map the human toxome, while representing a significant extension toward more formal risk assessment compared to the profiling and prioritization approaches offered by programs such as the EPA’s ToxCast effort. PMID:21993955

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.

Sirc-cvs cytotoxicity test: an alternative for predicting rodent acute systemic toxicity.

Science.gov (United States)

Kitagaki, Masato; Wakuri, Shinobu; Hirota, Morihiko; Tanaka, Noriho; Itagaki, Hiroshi

2006-10-01

An in vitro crystal violet staining method using the rabbit cornea-derived cell line (SIRC-CVS) has been developed as an alternative to predict acute systemic toxicity in rodents. Seventy-nine chemicals, the in vitro cytotoxicity of which was already reported by the Multicenter Evaluation of In vitro Toxicity (MEIC) and ICCVAM/ECVAM, were selected as test compounds. The cells were incubated with the chemicals for 72 hrs and the IC(50) and IC(35) values (microg/mL) were obtained. The results were compared to the in vivo (rat or mouse) "most toxic" oral, intraperitoneal, subcutaneous and intravenous LD(50) values (mg/kg) taken from the RTECS database for each of the chemicals by using Pearson's correlation statistics. The following parameters were calculated: accuracy, sensitivity, specificity, prevalence, positive predictability, and negative predictability. Good linear correlations (Pearson's coefficient; r>0.6) were observed between either the IC(50) or the IC(35) values and all the LD(50) values. Among them, a statistically significant high correlation (r=0.8102, p50) values and the oral LD(50) values. By using the cut-off concentrations of 2,000 mg/kg (LD(50)) and 4,225 microg/mL (IC(50)), no false negatives were observed, and the accuracy was 84.8%. From this, it is concluded that this method could be used to predict the acute systemic toxicity potential of chemicals in rodents.

Prenatal developmental toxicity testing of petroleum substances: Application of the mouse embryonic stem cell test (EST) to compare in vitro potencies with potencies observed in vivo.

Science.gov (United States)

Kamelia, Lenny; Louisse, Jochem; de Haan, Laura; Rietjens, Ivonne M C M; Boogaard, Peter J

2017-10-01

Prenatal developmental toxicity (PDT) as observed with some petroleum substances (PS) has been associated with the presence of 3-7 ring polycyclic aromatic hydrocarbons (PAHs). In the present study, the applicability of ES-D3 cell differentiation assay of the EST to evaluate in vitro embryotoxicity potencies of PS and gas-to-liquid (GTL) products as compared to their in vivo potencies was investigated. DMSO-extracts of a range of PS, containing different amounts of PAHs, and GTL-products, which are devoid of PAHs, were tested in the ES-D3 cell proliferation and differentiation assays of the EST. The results show that PS inhibited the differentiation of ES-D3 cells into cardiomyocytes in a concentration-dependent manner at non-cytotoxic concentrations, and that their potency was proportional to their PAH content. In contrast, as expected, GTL-products did not inhibit ES-D3 cell viability or differentiation at all. The in vitro PDT potencies were compared to published in vivo PDT studies, and a good correlation was found between in vitro and in vivo results (R 2 =0.97). To conclude, our results support the hypothesis that PAHs are the primary inducers of the PDT in PS. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cellulose/soy protein isolate composite membranes: evaluations of in vitro cytocompatibility with Schwann cells and in vivo toxicity to animals.

Science.gov (United States)

Luo, Lihua; Gong, Wenrong; Zhou, Yi; Yang, Lin; Li, Daokun; Huselstein, Celine; Wang, Xiong; He, Xiaohua; Li, Yinping; Chen, Yun

2015-01-01

To evaluate the in vitro cytocompatibility of cellulose/soy protein isolate composite membranes (CSM) with Schwann cells and in vivo toxicity to animals. A series of cellulose/soy protein isolate composite membranes (CSM) were prepared by blending, solution casting and coagulation process. The cytocompatibility of the CSM to Schwann cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and by direct cells culture of Schwann cells on the surfaces of the CSM, respectively. The in vivo toxicity of the CSM to animals were also evaluated by acute toxicity testing, skin sensitization testing, pyrogen testing and intracutaneous stimulation testing, respectively, according to the ISO 10993 standard. The MTT assay showed that the cell viability of Schwann cells cultured in extracts from the CSM was higher than that from the neat cellulose membrane without containing SPI component. The direct cells culture indicated that the Schwann cells could attach and grow well on the surface of the CSM and the incorporation of SPI into cellulose contributed to improvement of cell adhesion and proliferation. The evaluations of in vivo biological safety suggested that the CSM showed no acute toxicity, no skin sensitization and no intracutaneous stimulation to the experimental animals. The CSM had in vitro cytocompatibility with Schwann cells and biological safety to animals, suggesting potential for the applications as nerve conduit for the repair of nerve defect.

Etoposide; colchicine; mitomycin C and cyclophosphamide tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster lung (CHL) cells at Covance laboratories; Harrogate UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Fowler, Paul; Whitwell, James; Jeffrey, Laura; Young, Jamie; Smith, Katie; Kirkland, David

2010-10-29

The following genotoxic chemicals were tested in the in vitro micronucleus assay, at Covance Laboratories, Harrogate, UK in the Chinese hamster lung cell line CHL. Etoposide (a topoisomerase inhibitor), colchicine (an aneugen), mitomycin C (a DNA cross linking agent) and cyclophosphamide (an alkylating agent requiring metabolic activation) were treated with and without cytokinesis block (by addition of cytochalasin B). This work formed part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 for the in vitro micronucleus test. The toxicity measures used, detecting both cytostasis and cell death, were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index or cytokinesis blocked proliferation index in the presence of cytokinesis block. All of the chemicals tested gave significant increases in the percentage of micronucleated cells with and without cytokinesis block at concentrations giving approximately 60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcomes from this series of tests support the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

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

Directory of Open Access Journals (Sweden)

Yang Yang

Full Text Available 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.

New and emerging technologies for genetic toxicity testing.

Science.gov (United States)

Lynch, Anthony M; Sasaki, Jennifer C; Elespuru, Rosalie; Jacobson-Kram, David; Thybaud, Véronique; De Boeck, Marlies; Aardema, Marilyn J; Aubrecht, Jiri; Benz, R Daniel; Dertinger, Stephen D; Douglas, George R; White, Paul A; Escobar, Patricia A; Fornace, Albert; Honma, Masamitsu; Naven, Russell T; Rusling, James F; Schiestl, Robert H; Walmsley, Richard M; Yamamura, Eiji; van Benthem, Jan; Kim, James H

2011-04-01

The International Life Sciences Institute (ILSI) Health and Environmental Sciences Institute (HESI) Project Committee on the Relevance and Follow-up of Positive Results in In Vitro Genetic Toxicity (IVGT) Testing established an Emerging Technologies and New Strategies Workgroup to review the current State of the Art in genetic toxicology testing. The aim of the workgroup was to identify promising technologies that will improve genotoxicity testing and assessment of in vivo hazard and risk, and that have the potential to help meet the objectives of the IVGT. As part of this initiative, HESI convened a workshop in Washington, DC in May 2008 to discuss mature, maturing, and emerging technologies in genetic toxicology. This article collates the abstracts of the New and Emerging Technologies Workshop together with some additional technologies subsequently considered by the workgroup. Each abstract (available in the online version of the article) includes a section addressed specifically to the strengths, weaknesses, opportunities, and threats associated with the respective technology. Importantly, an overview of the technologies and an indication of how their use might be aligned with the objectives of IVGT are presented. In particular, consideration was given with regard to follow-up testing of positive results in the standard IVGT tests (i.e., Salmonella Ames test, chromosome aberration assay, and mouse lymphoma assay) to add weight of evidence and/or provide mechanism of action for improved genetic toxicity risk assessments in humans. Copyright © 2010 Wiley-Liss, Inc.

Assessment of pyrrolizidine alkaloid-induced toxicity in an in vitro screening model.

Science.gov (United States)

Li, Yan Hong; Kan, Winnie Lai Ting; Li, Na; Lin, Ge

2013-11-25

Pyrrolizidine alkaloids (PAs) are a group of heterocyclic phytotoxins present in a wide range of plants. The consumption of PA-containing medicinal herbs or PA-contaminated foodstuffs has long been reported to cause human hepatotoxicity. However, the degrees of hepatotoxicity of different PAs are unknown, which makes it difficult to determine a universal threshold of toxic dose of individual PAs for safe regulation of PA-containing natural products. The aim of the present study is to develop a simple and convenient in vitro model to assess the hepatotoxicity of different PAs. Six common cytotoxicity assays were used to evaluate the hepatotoxicity of different PAs in human hepatocellular carcinoma HepG2 cells. The combination of MTT and bromodeoxyuridine incorporation (BrdU) assays demonstrated to be a suitable method to evaluate the toxic potencies of various PAs in HepG2 cells, and the results indicated that otonecine-type PA (clivorine: IC₂₀=0.013 ± 0.004 mM (MTT), 0.066 ± 0.031 mM (BrdU)) exhibited significantly higher cytotoxic and anti-proliferative effects than retronecine-type PA (retrorsine: IC₂₀=0.27 ± 0.07 mM (MTT), 0.19 ± 0.03 mM (BrdU)). While as expected, the known less toxic platyphylline-type PA (platyphylline: IC₂₀=0.85 ± 0.11 mM (MTT), 1.01 ± 0.40 mM (BrdU)) exhibited significantly less toxicity. The different cytotoxic and anti-proliferative potencies of various PAs in the same retronecine-type could also be discriminated by using the combined MTT and BrdU assays. In addition, the developed assays were further utilized to test alkaloid extract of Gynura segetum, a senecionine and seneciphylline-containing herb, the overall cytotoxicity of two PAs in the extract was comparable to that of these two PAs tested individually. Using the developed in vitro model, the cytotoxicity of different PAs and the extract of a PA-containing herb were investigated in parallel in one system, and their different hepatotoxic potencies were determined

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

Gaining acceptance for the use of in vitro toxicity assays and QIVIVE in regulatory risk assessment.

Science.gov (United States)

Meek, M E Bette; Lipscomb, John C

2015-06-05

Testing strategies are anticipated to increasingly rely on in vitro data as a basis to characterize early steps or key events in toxicity at relevant dose levels in human tissues. Such strategies require quantitative in vitro to in vivo extrapolation to characterize dose-response as a basis for comparison with exposure to estimate risk. Current experience in the incorporation of mechanistic and in vitro data in risk assessment is considered here in the context of identified principles to increase the potential for timely acceptance of more progressive and tailored testing strategies by the regulatory community. These principles are outlined as transitioning in a familiar context, tiering to acquire experience and increase confidence, contextual knowledge transfer to facilitate interpretation and communication, coordination and development of expertise and continuing challenge. A proposed pragmatic tiered data driven framework which includes increasing reliance on in vitro data and quantitative in vitro to in vivo extrapolation is considered in the context of these principles. Based on this analysis, possible additional steps that might facilitate timely evolution and potentially, uptake are identified. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

In vitro toxicity test and searching the possibility of cancer cell line extermination by magnetic heating with using Fe3O4 magnetic fluid

International Nuclear Information System (INIS)

Pham Hoai Linh; Nguyen Chi Thuan; Nguyen Anh Tuan; Pham Van Thach; Nguyen Xuan Phuc; Le Van Hong; Tran Cong Yen; Nguyen Thi Quy; Hoang Thi My Nhung; Phi Thi Xuyen

2009-01-01

A Fe 3 O 4 based magnetic fluid with different concentrations ranged between 0.15 ng/cell to 10 ng/cell (nano gram/cell) was used in the in vitro toxicity test on several cancer cell lines, Sarcoma 180, HeLa and H358. It shows that the fluid with a concentration of Fe 3 O 4 below 1.2 ng/cell is completely non-toxic for these cell lines. Even through in the presence of the highest concentration of 10 ng/cell, the cell viability still reaches more than 60%. The magnetic fluid with Fe 3 O 4 concentration of about 0.1 ng/cell was also used to search ex-vivo the possibility of Sarcoma 180 extermination by magnetic heating with an AC field of 120Oe and 184 KHz. The result shows that after a heat treatment for 30 min., 40% of Sarcoma 180 cells was killed.

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,

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; Haïk, Stéphane

2013-03-01

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 (PrP(Sc)) of the host-encoded prion protein (PrP(C)), 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, PrP(Sc) 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.

Toxicity Estimation Software Tool (TEST)

Science.gov (United States)

The Toxicity Estimation Software Tool (TEST) was developed to allow users to easily estimate the toxicity of chemicals using Quantitative Structure Activity Relationships (QSARs) methodologies. QSARs are mathematical models used to predict measures of toxicity from the physical c...

Toxic effects of ethylene oxide residues on bovine embryos in vitro.

Science.gov (United States)

Holyoak, G R; Wang, S; Liu, Y; Bunch, T D

1996-04-15

The potential of ethylene oxide (EtO) residues in exposed plastic tissue culture dishes to adversely affect bovine oocyte maturation, fertilization and subsequent embryonic development was monitored. In experiment 1, the effects of aeration time and aeration combined with washing of EtO-gassed culture dishes on the extent of residual toxicity were investigated. There was no cleavage in any treatment in which oocytes were matured and fertilized in dishes exposed to EtO. EtO residues caused functional degeneration of oocytes even when culture dishes were aerated for more than 12 days post EtO-exposure and repeatedly washed. In experiment 2, the residual toxicity of EtO gas on in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) were evaluated. Cleavage rate significantly decreased and post-cleavage development was retarded in ova maintained in dishes treated with EtO either during IVM or IVF. EtO residues may be more detrimental to spermatozoa than to oocytes which may have been the primary cause of fertilization failure during IVF.

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.

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

Directory of Open Access Journals (Sweden)

Edith Aberdam

Full Text Available 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.

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.

Cadmium chloride, benzo[a]pyrene and cyclophosphamide tested in the in vitro mammalian cell micronucleus test (MNvit) in the human lymphoblastoid cell line TK6 at Covance laboratories, Harrogate UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Fowler, Paul; Whitwell, James; Jeffrey, Laura; Young, Jamie; Smith, Katie; Kirkland, David

2010-10-29

The following genotoxic chemicals were tested in the in vitro micronucleus assay, at Covance Laboratories, Harrogate, UK in the human lymphoblastoid cell line TK6. Cadmium chloride (an inorganic carcinogen), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation) and cyclophosphamide (an alkylating agent requiring metabolic activation) were treated with and without cytokinesis block (by addition of cytochalasin B). This work formed part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 for the in vitro micronucleus test. The toxicity measures used, capable of detecting both cytostasis and cell death, were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index or cytokinesis blocked proliferation index in the presence of cytokinesis block. All of the chemicals tested gave significant increases in the percentage of micronucleated cells with and without cytokinesis block at concentrations giving approximately 60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcomes from this series of tests support the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in the in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

Sub-chronic toxicity of low concentrations of industrial volatile organic pollutants in vitro

International Nuclear Information System (INIS)

McDermott, Catherine; Allshire, Ashley; Pelt, Frank N.A.M. van; Heffron, James J.A.

2007-01-01

Organic solvents form an important class of pollutants in the ambient air and have been associated with neurotoxicity and immunotoxicity in humans. Here we investigated the biological effects of sub-chronic exposure to industrially important volatile organic solvents in vitro. Jurkat T cells were exposed to toluene, n-hexane and methyl ethyl ketone (MEK) individually for 5 days and solvent exposure levels were confirmed by headspace gas chromatography. A neuroblastoma cell line (SH-SY5Y) was exposed to toluene for the same period. Following exposure, cells were harvested and toxicity measured in terms of the following endpoints: membrane damage (LDH leakage), perturbations in intracellular free Ca 2+ , changes in glutathione redox status and dual-phosphorylation of MAP kinases ERK1/2, JNK and p38. The results show that sub-chronic exposure to the volatile organic solvents causes membrane damage, increased intracellular free calcium and altered glutathione redox status in both cell lines. However, acute and sub-chronic solvent exposure did not result in MAP kinase phosphorylation. Toxicity of the solvents tested increased with hydrophobicity. The lowest-observed-adverse-effect-levels (LOAELs) measured in vitro were close to blood solvent concentrations reported for individuals exposed to the agents at levels at or below their individual threshold limit values (TLVs)

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

Antimicrobial activity and toxicity in vitro and in vivo of Equisetum hyemale extracts

Directory of Open Access Journals (Sweden)

Geisiany Maria de Queiroz

2014-09-01

Full Text Available Equisetum hyemale L, (Equisetaceae species is considered a medicinal plant used in the form of teas to combat infectious or inflammation diseases, presenting several compounds related to these actions, There are no extensive studies about the use against different microbial groups as well as for the toxicity, The objective of these studies was for the first time evaluated the antimicrobial activity against oral microorganisms and the in vitro and in vivo toxicity of 70% ethanol and methanol E, hyemale extracts, Antimicrobial activity assays were performed by broth microdilution technique to determine the Minimum Inhibitory Concentration (MIC and the cytoxicity was assayed in vitro and acute toxicity in vivo was performed with mice, The methanol extracts, showed better antimicrobial activity against oral microorganisms whit MIC of 0.5 mg/mL, Both extracts presented low cytotoxicity even in high concentrations and the 70% ethanol extract of E, hyemale did not present toxicity inducing significant alterations and/or death in mice, This results suggests that both extracts exhibits great potential to therapeutic applications.

Evaluation of an alternative in vitro test battery for detecting reproductive toxicants in a grouping context

NARCIS (Netherlands)

Kroese, E.D.; Bosgra, S.; Buist, H.E.; Lewin, G.; Linden, S.C. van der; Man, H.Y.; Piersma, A.H.; Rorije, E.; Schulpen, S.H.W.; Schwarz, M.; Uibel, F.; Vugt-Lussenburg, B.M.A. van; Wolterbeek, A.P.M.; Burg, B. van der

2015-01-01

Previously we showed a battery consisting of CALUX transcriptional activation assays, the ReProGlo assay, and the embryonic stem cell test, and zebrafish embryotoxicity assay as 'apical' tests to correctly predict developmental toxicity for 11 out of 12 compounds, and to explain the one false

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.

Effectivity of advanced wastewater treatment: reduction of in vitro endocrine activity and mutagenicity but not of in vivo reproductive toxicity.

Science.gov (United States)

Giebner, Sabrina; Ostermann, Sina; Straskraba, Susanne; Oetken, Matthias; Oehlmann, Jörg; Wagner, Martin

2018-02-01

Conventional wastewater treatment plants (WWTPs) have a limited capacity to eliminate micropollutants. One option to improve this is tertiary treatment. Accordingly, the WWTP Eriskirch at the German river Schussen has been upgraded with different combinations of ozonation, sand, and granulated activated carbon filtration. In this study, the removal of endocrine and genotoxic effects in vitro and reproductive toxicity in vivo was assessed in a 2-year long-term monitoring. All experiments were performed with aqueous and solid-phase extracted water samples. Untreated wastewater affected several endocrine endpoints in reporter gene assays. The conventional treatment removed the estrogenic and androgenic activity by 77 and 95 %, respectively. Nevertheless, high anti-estrogenic activities and reproductive toxicity persisted. All advanced treatment technologies further reduced the estrogenic activities by additional 69-86 % compared to conventional treatment, resulting in a complete removal of up to 97 %. In the Ames assay, we detected an ozone-induced mutagenicity, which was removed by subsequent filtration. This demonstrates that a post treatment to ozonation is needed to minimize toxic oxidative transformation products. In the reproduction test with the mudsnail Potamopyrgus antipodarum, a decreased number of embryos was observed for all wastewater samples. This indicates that reproductive toxicants were eliminated by neither the conventional nor the advanced treatment. Furthermore, aqueous samples showed higher anti-estrogenic and reproductive toxicity than extracted samples, indicating that the causative compounds are not extractable or were lost during extraction. This underlines the importance of the adequate handling of wastewater samples. Taken together, this study demonstrates that combinations of multiple advanced technologies reduce endocrine effects in vitro. However, they did not remove in vitro anti-estrogenicity and in vivo reproductive toxicity. This

In Vivo and In Vitro Toxicity Evaluation of Hydroethanolic Extract of Kalanchoe brasiliensis (Crassulaceae) Leaves.

Science.gov (United States)

Fonseca, Aldilane Gonçalves; Ribeiro Dantas, Luzia Leiros Sena Fernandes; Fernandes, Júlia Morais; Zucolotto, Silvana Maria; Lima, Adley Antoninni Neves; Soares, Luiz Alberto Lira; Rocha, Hugo Alexandre Oliveira; Lemos, Telma Maria Araújo Moura

2018-01-01

The species Kalanchoe brasiliensis , known as "Saião , " has anti-inflammatory, antimicrobial, and antihistamine activities. It also has the quercetin and kaempferol flavonoids, which exert their therapeutic activities. With extensive popular use besides the defined therapeutical properties, the study of possible side effects is indispensable. The objective of this study is to evaluate the toxicity in vitro and in vivo from the hydroethanolic extract of the leaves of K. brasiliensis . The action of the extract (concentrations from 0.1 to 1000 uL/100 uL) in normal and tumor cells was evaluated using the MTT method. Acute toxicity and subchronic toxicity were evaluated in mice with doses of 250 to 1000 mg/kg orally, following recognized protocols. The in vitro results indicated cytotoxic activity for 3T3 cell line (normal) and 786-0 (kidney carcinoma), showing the activity to be concentration-dependent, reaching 92.23% cell inhibition. In vivo , the extract showed no significant toxicity; only liver changes related to acute toxicity and some signs of liver damage, combining biochemical and histological data. In general, the extract showed low or no toxicity, introducing itself as safe for use with promising therapeutic potential.

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......The Organisation for Economic Cooperation and Development is promoting the development and validation of mollusc toxicity tests within its test guidelines programme, eventually aiming for the standardization of mollusc apical toxicity tests. Through collaborative work between academia, industry...... and stakeholders, this study aims to develop innovative partial life-cycle tests on the reproduction of the freshwater gastropods Potamopyrgus antipodarum and Lymnaea stagnalis, which are relevant candidate species for the standardization of mollusc apical toxicity tests assessing reprotoxic effects of chemicals...

5-Fluorouracil, colchicine, benzo[a]pyrene and cytosine arabinoside tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster V79 cells at Covance Laboratories, Harrogate, UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Whitwell, James; Fowler, Paul; Allars, Sarah; Jenner, Karen; Lloyd, Melvyn; Wood, Debbie; Smith, Katie; Young, Jamie; Jeffrey, Laura; Kirkland, David

2010-10-29

The reference genotoxic agents 5-fluorouracil (a nucleoside analogue, characterised by a steep dose response profile), colchicine (an aneugen that inhibits tubulin polymerisation), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation) and cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair) were tested in the in vitro micronucleus assay using the Chinese hamster V79 cell line at Covance Laboratories, Harrogate, UK. All chemicals were treated in the absence and presence of cytokinesis block (via addition of cytochalasin B) with this work forming part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 on the In Vitro Mammalian Cell Micronucleus Test (MNvit). The toxicity measures used, detecting a possible combination of both cytostasis and cell death (though not cell death directly), were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index in the presence of cytokinesis block. All of the chemicals tested either gave marked increases in the percentage of micronucleated cells with and without cytokinesis block, or did not induce micronuclei at concentrations giving approximately 50-60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcome from this series of tests supports the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

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...

Multi-Organ toxicity demonstration in a functional human in vitro system composed of four organs.

Science.gov (United States)

Oleaga, Carlota; Bernabini, Catia; Smith, Alec S T; Srinivasan, Balaji; Jackson, Max; McLamb, William; Platt, Vivien; Bridges, Richard; Cai, Yunqing; Santhanam, Navaneetha; Berry, Bonnie; Najjar, Sarah; Akanda, Nesar; Guo, Xiufang; Martin, Candace; Ekman, Gail; Esch, Mandy B; Langer, Jessica; Ouedraogo, Gladys; Cotovio, Jose; Breton, Lionel; Shuler, Michael L; Hickman, James J

2016-02-03

We report on a functional human model to evaluate multi-organ toxicity in a 4-organ system under continuous flow conditions in a serum-free defined medium utilizing a pumpless platform for 14 days. Computer simulations of the platform established flow rates and resultant shear stress within accepted ranges. Viability of the system was demonstrated for 14 days as well as functional activity of cardiac, muscle, neuronal and liver modules. The pharmacological relevance of the integrated modules were evaluated for their response at 7 days to 5 drugs with known side effects after a 48 hour drug treatment regime. The results of all drug treatments were in general agreement with published toxicity results from human and animal data. The presented phenotypic culture model exhibits a multi-organ toxicity response, representing the next generation of in vitro systems, and constitutes a step towards an in vitro "human-on-a-chip" assay for systemic toxicity screening.

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.

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.

In Vivo and In Vitro Toxicity Evaluation of Hydroethanolic Extract of Kalanchoe brasiliensis (Crassulaceae Leaves

Directory of Open Access Journals (Sweden)

Aldilane Gonçalves Fonseca

2018-01-01

Full Text Available The species Kalanchoe brasiliensis, known as “Saião,” has anti-inflammatory, antimicrobial, and antihistamine activities. It also has the quercetin and kaempferol flavonoids, which exert their therapeutic activities. With extensive popular use besides the defined therapeutical properties, the study of possible side effects is indispensable. The objective of this study is to evaluate the toxicity in vitro and in vivo from the hydroethanolic extract of the leaves of K. brasiliensis. The action of the extract (concentrations from 0.1 to 1000 uL/100 uL in normal and tumor cells was evaluated using the MTT method. Acute toxicity and subchronic toxicity were evaluated in mice with doses of 250 to 1000 mg/kg orally, following recognized protocols. The in vitro results indicated cytotoxic activity for 3T3 cell line (normal and 786-0 (kidney carcinoma, showing the activity to be concentration-dependent, reaching 92.23% cell inhibition. In vivo, the extract showed no significant toxicity; only liver changes related to acute toxicity and some signs of liver damage, combining biochemical and histological data. In general, the extract showed low or no toxicity, introducing itself as safe for use with promising therapeutic potential.

Mixture toxicity of wood preservative products in the fish embryo toxicity test.

Science.gov (United States)

Coors, Anja; Dobrick, Jan; Möder, Monika; Kehrer, Anja

2012-06-01

Wood preservative products are used globally to protect wood from fungal decay and insects. We investigated the aquatic toxicity of five commercial wood preservative products, the biocidal active substances and some formulation additives contained therein, as well as six generic binary mixtures of the active substances in the fish embryo toxicity test (FET). Median lethal concentrations (LC50) of the single substances, the mixtures, and the products were estimated from concentration-response curves and corrected for concentrations measured in the test medium. The comparison of the experimentally observed mixture toxicity with the toxicity predicted by the concept of concentration addition (CA) showed less than twofold deviation for all binary mixtures of the active substances and for three of the biocidal products. A more than 60-fold underestimation of the toxicity of the fourth product by the CA prediction was detected and could be explained fully by the toxicity of one formulation additive, which had been labeled as a hazardous substance. The reason for the 4.6-fold underestimation of toxicity of the fifth product could not be explained unambiguously. Overall, the FET was found to be a suitable screening tool to verify whether the toxicity of formulated wood preservatives can reliably be predicted by CA. Applied as a quick and simple nonanimal screening test, the FET may support approaches of applying component-based mixture toxicity predictions within the environmental risk assessment of biocidal products, which is required according to European regulations. Copyright © 2012 SETAC.

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.

Evaluation of metals, metalloids, and ash mixture toxicity using sediment toxicity testing.

Science.gov (United States)

Stojak, Amber; Bonnevie, Nancy L; Jones, Daniel S

2015-01-01

In December 2008, a release of 4.1 million m(3) of coal ash from the Tennessee Valley Authority Kingston Fossil Plant occurred. Ash washed into the Emory River and migrated downstream into the Clinch and Tennessee Rivers. A Baseline Ecological Risk Assessment evaluated risks to ecological receptors from ash in the river system post-dredging. This article describes the approach used and results from sediment toxicity tests, discussing any causal relationships between ash, metals, and toxicity. Literature is limited in the realm of aquatic coal combustion residue (CCR) exposures and the potential magnitude of effects on benthic invertebrates. Sediment samples along a spectrum of ash content were used in a tiered toxicity testing approach and included a combination of 10 day sediment toxicity acute tests and longer-term, partial life cycle "definitive" tests with 2 species (Hyalella azteca and Chironomus dilutus). Arsenic, and to a lesser extent Se, in the ash was the most likely toxicant causing observed effects in the laboratory toxicity tests. Sites in the Emory River with the greatest statistical and biologically significant effects had As concentrations in sediments twice the probable effects concentration of 33 mg/kg. These sites contained greater than 50% ash. Sites with less than approximately 50% ash in sediments exhibited fewer significant toxic responses relative to the reference sediment in the laboratory. The results discussed here present useful evidence of only limited effects occurring from a worst-case exposure pathway. These results provided a valuable line of evidence for the overall assessment of risks to benthic invertebrates and to other ecological receptors, and were crucial to risk management and development of project remediation goals. © 2014 SETAC.

Synthesis and in vitro toxicity of new dodecaborate-containing amino acids

International Nuclear Information System (INIS)

Slepukhina, Irina; Gabel, Detlef

2006-01-01

Two unnatural, boron-containing amino acids were synthesized by alkylation of S-(2-cyanoethyl)-thio-undecahydro-closo-dodecaborate(2-). S-(2-amino-2-carboxylpropyl)-thio-undecahydro-closo-dodecaborate (2-), containing a quaternary carbon atom, and O-(5-amino-5-carboxylpentyl)-oxy-undecahydro-closo-dodecaborate(2-) were evaluated for in vitro toxicity using V 79 Chinese hamster cells. (author)

[Toxicity of chongqing acid fogwater on rabbit alveolar macrophages in vitro].

Science.gov (United States)

Shu, W Q; Zhuo, J B

1992-07-01

We collected acid fogwater on a fogday and observed its toxic effects on rabbits' pulmonary alveolar macrophages (AM) in vitro. The fogwater was diluted into 4 concentrations: 1, 1/10, 1/100, and 1/1000 of the original fogwater and the exposure time was 12 hours. The results showed that both the AM's viability and the phagocytic capacity were depressed significantly, but the AM's lysosomal enzyme--acid phosphatase activity was found to be stimulated to increase. All these changes were directly correlated with the degree of pollution of the fogwater. Of these three toxicity indices, the most sensitive one was the change of AM's phagocytic capacity.

Portable, accurate toxicity testing

International Nuclear Information System (INIS)

Sabate, R.W.; Stiffey, A.V.; Dewailly, E.L.; Hinds, A.A.; Vieaux, G.J.

1994-01-01

Ever tightening environmental regulations, severe penalties for non-compliance, and expensive remediation costs have stimulated development of methods to detect and measure toxins. Most of these methods are bioassays that must be performed in the laboratory; none previously devised has been truly portable. The US Army, through the Small Business Innovative Research program, has developed a hand-held, field deployable unit for testing toxicity of battlefield water supplies. This patented system employs the measurable quenching, in the presence of toxins, of the natural bioluminescence produced by the marine dinoflagellate alga Pyrocystis lunula. The procedure's inventor used it for years to measure toxicity concentrations of chemical warfare agents actually, their simulants, primarily in the form of pesticides and herbicides plus assorted toxic reagents, waterbottom samples, drilling fluids, even blood. While the procedure is more precise, cheaper, and faster than most bioassays, until recently it was immobile. Now it is deployable in the field. The laboratory apparatus has been proven to be sensitive to toxins in concentrations as low as a few parts per billion, repeatable within a variation of 10% or less, and unlike some other bioassays effective in turbid or colored media. The laboratory apparatus and the hand-held tester have been calibrated with the EPA protocol that uses the shrimplike Mysidopsis bahia. The test organism tolerates transportation well, but must be rested a few hours at the test site for regeneration of its light-producing powers. Toxicity now can be measured confidently in soils, water columns, discharge points, and many other media in situ. Most significant to the oil industry is that drilling fluids can be monitored continuously on the rig

Evaluation of seven in vitro alternatives for ocular safety testing.

Science.gov (United States)

Bruner, L H; Kain, D J; Roberts, D A; Parker, R D

1991-07-01

Seven in vitro assays were evaluated to determine if any were useful as screening procedures in ocular safety assessment. Seventeen test materials (chemicals, household cleaners, hand soaps, dishwashing liquids, shampoos, and liquid laundry detergents) were tested in each assay. In vivo ocular irritation scores for the materials were obtained from existing rabbit low volume eye test (LVET) data. The seven assays evaluated included the silicon microphysiometer (SM), luminescent bacteria toxicity test (LBT), neutral red assay (NR), total protein assay (TP), Tetrahymena thermophila motility assay (TTMA), bovine eye/chorioallantoic membrane assay (BE/CAM), and the EYTEX system (ETS). For the seventeen materials used in this study there was a significant correlation between the in vivo irritant potential and in vitro data for all the tests except the EYTEX System (SM, r = -0.87; LBT, r = -0.91; NR, r = -0.85; TTMA, r = 0.78; TP, r = -0.86; ETS, r = 0.29). The irritation classifications provided by the BE/CAM also did not correspond with the actual in vivo irritancy potential of the test materials. The result of this study suggested it may be possible to classify materials into broad irritancy categories with some of the assays. This would allow their use as screens prior to limited in vivo confirmation in the ocular safety assessment process.

In vitro approaches to evaluate toxicity induced by organotin compounds tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) in neuroblastoma cells.

Science.gov (United States)

Ferreira, Martiña; Blanco, Lucía; Garrido, Alejandro; Vieites, Juan M; Cabado, Ana G

2013-05-01

The toxic effects of the organotin compounds (OTCs) monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) were evaluated in vitro in a neuroblastoma human cell line. Mechanisms of cell death, apoptosis versus necrosis, were studied by using several markers: inhibition of cell viability and proliferation, F-actin, and mitochondrial membrane potential changes as well as reactive oxygen species (ROS) production and DNA fragmentation. The most toxic effects were detected with DBT and TBT even at very low concentrations (0.1-1 μM). In contrast, MBT induced lighter cytotoxic changes at the higher doses tested. None of the studied compounds stimulated propidium iodide uptake, although the most toxic chemical, TBT, caused lactate dehydrogenase release at the higher concentrations tested. These findings suggest that in neuroblastoma, OTC-induced cytotoxicity involves different pathways depending on the compound, concentration, and incubation time. A screening method for DBT and TBT quantification based on cell viability loss was developed, allowing a fast detection alternative to complex methodology.

Evaluating the Zebrafish Embryo Toxicity Test for Pesticide ...

Science.gov (United States)

Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more resource-intensive, juvenile fish acute toxicity tests. However, there is also evidence that fish embryos are less sensitive than juvenile fish for certain types of chemicals, including neurotoxicants. The utility of fish embryos for pesticide hazard assessment was investigated by comparing published zebrafish embryo toxicity data from pesticides with median lethal concentration 50% (LC50) data for juveniles of 3 commonly tested fish species: rainbow trout, bluegill sunfish, and sheepshead minnow. A poor, albeit significant, relationship (r2 = 0.28; p embryo and juvenile fish toxicity when pesticides were considered as a single group, but a much better relationship (r2 = 0.64; p embryo toxicity test endpoints are particularly insensitive to neurotoxicants. These results indicate that it is still premature to replace juvenile fish toxicity tests with embryo-based tests such as the Organisation for Economic Co-op

TEST (Toxicity Estimation Software Tool) Ver 4.1

Science.gov (United States)

The Toxicity Estimation Software Tool (T.E.S.T.) has been developed to allow users to easily estimate toxicity and physical properties using a variety of QSAR methodologies. T.E.S.T allows a user to estimate toxicity without requiring any external programs. Users can input a chem...

Good cell culture practices &in vitro toxicology.

Science.gov (United States)

Eskes, Chantra; Boström, Ann-Charlotte; Bowe, Gerhard; Coecke, Sandra; Hartung, Thomas; Hendriks, Giel; Pamies, David; Piton, Alain; Rovida, Costanza

2017-12-01

Good Cell Culture Practices (GCCP) is of high relevance to in vitro toxicology. The European Society of Toxicology In Vitro (ESTIV), the Center for Alternatives for Animal Testing (CAAT) and the In Vitro Toxicology Industrial Platform (IVTIP) joined forces to address by means of an ESTIV 2016 pre-congress session the different aspects and applications of GCCP. The covered aspects comprised the current status of the OECD guidance document on Good In Vitro Method Practices, the importance of quality assurance for new technological advances in in vitro toxicology including stem cells, and the optimized implementation of Good Manufacturing Practices and Good Laboratory Practices for regulatory testing purposes. General discussions raised the duality related to the difficulties in implementing GCCP in an academic innovative research framework on one hand, and on the other hand, the need for such GCCP principles in order to ensure reproducibility and robustness of in vitro test methods for toxicity testing. Indeed, if good cell culture principles are critical to take into consideration for all uses of in vitro test methods for toxicity testing, the level of application of such principles may depend on the stage of development of the test method as well as on the applications of the test methods, i.e., academic innovative research vs. regulatory standardized test method. Copyright © 2017 Elsevier Ltd. All rights reserved.

OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing

NARCIS (Netherlands)

Busquet, F.; Strecker, R.; Rawlings, J.M.; Belanger, S.E.; Braunbeck, T.; Carr, G.J.; Cenijn, P.H.; Fochtman, P.; Gourmelon, A.; Hübler, N.; Kleensang, A.; Knöbel, M.; Kussatz, C.; Legler, J.; Lillicrap, A.; Martínez-Jerónimo, F.; Polleichtner, C.; Rzodeczko, H.; Salinas, E.; Schneider, K.E.; Scholz, S.; van den Brandhof, E.J.; van der Ven, L.T.; Walter-Rohde, S.; Weigt, S.; Witters, H.; Halder, M.

2014-01-01

A The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were

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-...... days to 2 days (minitest as well as larger volume tests) in order to avoid excessive biomass growth. Shortening tests to 2 days appears necessary if light intensity and temperature are near the upper limits of the intervals stated in the ISO standard.......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......-response curves were obtained with the ISO standard test and the minitest for potassium dichromate and 3,5-dichlorophenol. The minitest is conveniently carried out using 2.5 ml test volume in 20 ml glass scintillation vials, placed on a microplate shaker or on an ordinary shaking table, but smaller containers...

OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

Science.gov (United States)

Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

2014-08-01

The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

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.

Safety evaluation of food contact paper and board using chemical tests and in vitro bioassays: role of known and unknown substances.

Science.gov (United States)

Honkalampi-Hämäläinen, U; Bradley, E L; Castle, L; Severin, I; Dahbi, L; Dahlman, O; Lhuguenot, J-C; Andersson, M A; Hakulinen, P; Hoornstra, D; Mäki-Paakkanen, J; Salkinoja-Salonen, M; Turco, L; Stammati, A; Zucco, F; Weber, A; von Wright, A

2010-03-01

In vitro toxicological tests have been proposed as an approach to complement the chemical safety assessment of food contact materials, particularly those with a complex or unknown chemical composition such as paper and board. Among the concerns raised regarding the applicability of in vitro tests are the effects of interference of the extractables on the outcome of the cytotoxicity and genotoxicity tests applied and the role of known compounds present in chemically complex materials, such as paper and board, either as constituents or contaminants. To answer these questions, a series of experiments were performed to assess the role of natural substances (wood extracts, resin acids), some additives (diisopropylnaphthalene, phthalates, acrylamide, fluorescent whitening agents) and contaminants (2,4-diaminotoluene, benzo[a]pyrene) in the toxicological profile of paper and board. These substances were individually tested or used to spike actual paper and board extracts. The toxic concentrations of diisopropylnaphthalenes and phthalates were compared with those actually detected in paper and board extracts showing conspicuous toxicity. According to the results of the spiking experiments, the extracts did not affect the toxicity of tested chemicals nor was there any significant metabolic interference in the cases where two compounds were used in tests involving xenobiotic metabolism by the target cells. While the identified substances apparently have a role in the cytotoxicity of some of the project samples, their presence does not explain the total toxicological profile of the extracts. In conclusion, in vitro toxicological testing can have a role in the safety assessment of chemically complex materials in detecting potentially harmful activities not predictable by chemical analysis alone.

In vitro Assessment of Hg Toxicity in Hepatocytes from Heat-Stressed Atlantic Salmon.

Science.gov (United States)

Olsvik, Pål A; Waagbø, Rune; Hevrøy, Ernst M; Remø, Sofie C; Søfteland, Liv

2016-11-01

Global warming may alter the bioavailability of contaminants in aquatic environments. In this work, mercury (Hg 2+ ) toxicity was studied in cells obtained from Atlantic salmon smolt kept at 15 °C (optimal growth temperature) for 3 months or at a stepwise increase to 20 °C (temperature-stress) during 3 months prior to cell harvest to evaluate whether acclimation temperature affects Hg toxicity. To examine possible altered dietary requirements in warmer seas, one group of fish following the stepwise temperature regimes was fed a diet spiked with antioxidants. Atlantic salmon hepatocytes were exposed in vitro to 0, 1.0, or 100 μM Hg 2+ for 48 h. Cytotoxicity, determined as electrical impedance changes with the xCELLigence system, and transcriptional responses, determined with RT-qPCR, were assessed as measures of toxicity. The results showed that inorganic Hg at a concentration up to 100 μM is not cytotoxic to Atlantic salmon hepatocytes. Significance and directional responses of the 18 evaluated target genes suggest that both Hg and temperature stress affected the transcription of genes encoding proteins involved in the protection against ROS-generated oxidative stress. Both stressors also affected the transcription of genes linked to lipid metabolism. Spiking the diet with antioxidants resulted in higher concentrations of Se and vitamin C and reduced concentration of Hg in the liver in vivo, but no interactions were seen between the dietary supplementation of antioxidants and Hg toxicity in vitro. In conclusion, no evidence was found suggesting that inorganic Hg is more toxic in cells harvested from temperature-stressed fish.

2-Aminoanthracene, 5-fluorouracil, colchicine, benzo[a]pyrene, cadmium chloride and cytosine arabinoside tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster ovary (CHO) cells at Covance Laboratories, Harrogate UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Whitwell, James; Fowler, Paul; Allars, Sarah; Jenner, Karen; Lloyd, Melvyn; Wood, Debbie; Smith, Katie; Young, Jamie; Jeffrey, Laura; Kirkland, David

2010-10-29

The reference genotoxic agents 2-aminoanthracene (a metabolism dependent weak clastogen), 5-fluorouracil (a nucleoside analogue, characterised by a steep dose response profile), colchicine (an aneugen that inhibits tubulin polymerisation), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation), cadmium chloride (an inorganic carcinogen), and cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair) were tested in the in vitro micronucleus assay using the Chinese hamster ovary (CHO) cell line at Covance Laboratories, Harrogate, UK. All chemicals were treated in the absence and presence of cytokinesis block (via addition of cytochalasin B) with this work forming part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 on the In vitro Mammalian Cell Micronucleus Test (MNvit). The toxicity measures used, detecting a possible combination of both cytostasis and cell death (though not cell death directly), were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index in the presence of cytokinesis block. All of the chemicals tested either gave marked positive increases in the percentage of micronucleated cells with and without cytokinesis block, or did not induce micronuclei at concentrations giving approximately 50-60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcome from this series of tests supports the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

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

Classification of baseline toxicants for QSAR predictions to replace fish acute toxicity studies.

Science.gov (United States)

Nendza, Monika; Müller, Martin; Wenzel, Andrea

2017-03-22

Fish acute toxicity studies are required for environmental hazard and risk assessment of chemicals by national and international legislations such as REACH, the regulations of plant protection products and biocidal products, or the GHS (globally harmonised system) for classification and labelling of chemicals. Alternative methods like QSARs (quantitative structure-activity relationships) can replace many ecotoxicity tests. However, complete substitution of in vivo animal tests by in silico methods may not be realistic. For the so-called baseline toxicants, it is possible to predict the fish acute toxicity with sufficient accuracy from log K ow and, hence, valid QSARs can replace in vivo testing. In contrast, excess toxicants and chemicals not reliably classified as baseline toxicants require further in silico, in vitro or in vivo assessments. Thus, the critical task is to discriminate between baseline and excess toxicants. For fish acute toxicity, we derived a scheme based on structural alerts and physicochemical property thresholds to classify chemicals as either baseline toxicants (=predictable by QSARs) or as potential excess toxicants (=not predictable by baseline QSARs). The step-wise approach identifies baseline toxicants (true negatives) in a precautionary way to avoid false negative predictions. Therefore, a certain fraction of false positives can be tolerated, i.e. baseline toxicants without specific effects that may be tested instead of predicted. Application of the classification scheme to a new heterogeneous dataset for diverse fish species results in 40% baseline toxicants, 24% excess toxicants and 36% compounds not classified. Thus, we can conclude that replacing about half of the fish acute toxicity tests by QSAR predictions is realistic to be achieved in the short-term. The long-term goals are classification criteria also for further groups of toxicants and to replace as many in vivo fish acute toxicity tests as possible with valid QSAR

Integrated testing strategies for toxicity employing new and existing technologies.

Science.gov (United States)

Combes, Robert D; Balls, Michael

2011-07-01

We have developed individual, integrated testing strategies (ITS) for predicting the toxicity of general chemicals, cosmetics, pharmaceuticals, inhaled chemicals, and nanoparticles. These ITS are based on published schemes developed previously for the risk assessment of chemicals to fulfil the requirements of REACH, which have been updated to take account of the latest developments in advanced in chemico modelling and in vitro technologies. In addition, we propose an ITS for neurotoxicity, based on the same principles, for incorporation in the other ITS. The technologies are deployed in a step-wise manner, as a basis for decision-tree approaches, incorporating weight-of-evidence stages. This means that testing can be stopped at the point where a risk assessment and/or classification can be performed, with labelling in accordance with the requirements of the regulatory authority concerned, rather than following a checklist approach to hazard identification. In addition, the strategies are intelligent, in that they are based on the fundamental premise that there is no hazard in the absence of exposure - which is why pharmacokinetic modelling plays a key role in each ITS. The new technologies include the use of complex, three-dimensional human cell tissue culture systems with in vivo-like structural, physiological and biochemical features, as well as dosing conditions. In this way, problems of inter-species extrapolation and in vitro/in vivo extrapolation are minimised. This is reflected in the ITS placing more emphasis on the use of volunteers at the whole organism testing stage, rather than on existing animal testing, which is the current situation. 2011 FRAME.

78 FR 66700 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

Science.gov (United States)

2013-11-06

... additive for food Rat--Up-and-Down processing, and as Procedure. ingredient in aluminum Micronucleus Test... Toxicity to Fish; Acute Toxicity to Daphnia; Toxicity to Algae; Acute Toxicity to Mammals; Bacterial..., cold Study in Zebra Fish set, and sheet-fed (Brachydanio rerio). applications. Acute Toxicity Study in...

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

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

DEFF Research Database (Denmark)

Lagadic, Laurent; Holbech, Henrik; hutchinson, tom

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...... in an OECD Detailed Review Paper that identifies two relevant candidate species for developing freshwater tests: Potamopyrgus antipodarum and Lymnaea stagnalis. However, this review did not clarify which toxicity test design/conditions are the most appropriate for chemicals assessment. Therefore, a mollusc...... reproduction test guideline will be developed describing partial- and full- life-cycle test protocols in these species, so as to propose a balanced suite of apical mollusc toxicity tests applicable for the assessment of any type of chemical, including endocrine disruptors, as level 4 and 5 assays of the EDTA...

Acute oral toxicity test of chemical compounds in silkworms.

Science.gov (United States)

Usui, Kimihito; Nishida, Satoshi; Sugita, Takuya; Ueki, Takuro; Matsumoto, Yasuhiko; Okumura, Hidenobu; Sekimizu, Kazuhisa

2016-02-01

This study performed an acute oral toxicity test of 59 compounds in silkworms. These compounds are listed in OECD guidelines as standard substances for a cytotoxicity test, and median lethal dose (LD(50)) werecalculated for each compound. Acute oral LD(50) values in mammals are listed in OECD guidelines and acute oral LD(50) values in silkworms were determined in this study. R(2) for the correlation between LD(50) values in mammals and LD(50) values in silkworms was 0.66. In addition, the acute oral toxicity test in silkworms was performed by two different facilities, and test results from the facilities were highly reproducible. These findings suggest that an acute oral toxicity test in silkworms is a useful way to evaluate the toxicity of compounds in mammals.

In vitro functional screening as a means to identify new plasticizers devoid of reproductive toxicity

Energy Technology Data Exchange (ETDEWEB)

Boisvert, Annie; Jones, Steven; Issop, Leeyah [The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Department of Medicine, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Erythropel, Hanno C. [Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Papadopoulos, Vassilios [The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Department of Medicine, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Culty, Martine, E-mail: martine.culty@mcgill.ca [The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Department of Medicine, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada); Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada H4A 3J1 (Canada)

2016-10-15

Plasticizers are indispensable additives providing flexibility and malleability to plastics. Among them, several phthalates, including di (2-ethylhexyl) phthalate (DEHP), have emerged as endocrine disruptors, leading to their restriction in consumer products and creating a need for new, safer plasticizers. The goal of this project was to use in vitro functional screening tools to select novel non-toxic plasticizers suitable for further in vivo evaluation. A panel of novel compounds with satisfactory plasticizer properties and biodegradability were tested, along with several commercial plasticizers, such as diisononyl-cyclohexane-1,2-dicarboxylate (DINCH®). MEHP, the monoester metabolite of DEHP was also included as reference compound. Because phthalates target mainly testicular function, including androgen production and spermatogenesis, we used the mouse MA-10 Leydig and C18-4 spermatogonial cell lines as surrogates to examine cell survival, proliferation, steroidogenesis and mitochondrial integrity. The most promising compounds were further assessed on organ cultures of rat fetal and neonatal testes, corresponding to sensitive developmental windows. Dose-response studies revealed the toxicity of most maleates and fumarates, while identifying several dibenzoate and succinate plasticizers as innocuous on Leydig and germ cells. Interestingly, DINCH®, a plasticizer marketed as a safe alternative to phthalates, exerted a biphasic effect on steroid production in MA-10 and fetal Leydig cells. MEHP was the only plasticizer inducing the formation of multinucleated germ cells (MNG) in organ culture. Overall, organ cultures corroborated the cell line data, identifying one dibenzoate and one succinate as the most promising candidates. The adoption of such collaborative approaches for developing new chemicals should help prevent the development of compounds potentially harmful to human health. - Highlights: • Phthalate plasticizers exert toxic effects on male reproduction

In vitro functional screening as a means to identify new plasticizers devoid of reproductive toxicity

International Nuclear Information System (INIS)

Boisvert, Annie; Jones, Steven; Issop, Leeyah; Erythropel, Hanno C.; Papadopoulos, Vassilios; Culty, Martine

2016-01-01

Plasticizers are indispensable additives providing flexibility and malleability to plastics. Among them, several phthalates, including di (2-ethylhexyl) phthalate (DEHP), have emerged as endocrine disruptors, leading to their restriction in consumer products and creating a need for new, safer plasticizers. The goal of this project was to use in vitro functional screening tools to select novel non-toxic plasticizers suitable for further in vivo evaluation. A panel of novel compounds with satisfactory plasticizer properties and biodegradability were tested, along with several commercial plasticizers, such as diisononyl-cyclohexane-1,2-dicarboxylate (DINCH®). MEHP, the monoester metabolite of DEHP was also included as reference compound. Because phthalates target mainly testicular function, including androgen production and spermatogenesis, we used the mouse MA-10 Leydig and C18-4 spermatogonial cell lines as surrogates to examine cell survival, proliferation, steroidogenesis and mitochondrial integrity. The most promising compounds were further assessed on organ cultures of rat fetal and neonatal testes, corresponding to sensitive developmental windows. Dose-response studies revealed the toxicity of most maleates and fumarates, while identifying several dibenzoate and succinate plasticizers as innocuous on Leydig and germ cells. Interestingly, DINCH®, a plasticizer marketed as a safe alternative to phthalates, exerted a biphasic effect on steroid production in MA-10 and fetal Leydig cells. MEHP was the only plasticizer inducing the formation of multinucleated germ cells (MNG) in organ culture. Overall, organ cultures corroborated the cell line data, identifying one dibenzoate and one succinate as the most promising candidates. The adoption of such collaborative approaches for developing new chemicals should help prevent the development of compounds potentially harmful to human health. - Highlights: • Phthalate plasticizers exert toxic effects on male reproduction

76 FR 65385 - Testing of Certain High Production Volume Chemicals; Third Group of Chemicals

Science.gov (United States)

2011-10-21

... Mutations: Bacterial Reverse Mutation Test (in vitro): 40 CFR 799.9510. b. Chromosomal Damage: In Vitro... alternate test. 6. Mammalian Toxicity--Repeated Dose/Reproduction/Developmental--a. Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test: 40 CFR 799.9365. b...

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

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

KAUST Repository

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

2015-01-01

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.

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.

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

International Nuclear Information System (INIS)

Roszak, Joanna; Stępnik, Maciej; Nocuń, Marek; Ferlińska, Magdalena; Smok-Pieniążek, Anna; Grobelny, Jarosław; Tomaszewska, Emilia; Wąsowicz, Wojciech; Cieślak, Małgorzata

2013-01-01

Highlights: • Commercially available TiO 2 /Ag nanomaterials (NMs) showed higher cytotoxic effect than TiO 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 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 2 and TiO 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 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 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

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.

Simple test guidelines for screening oilspill sorbents for toxicity

International Nuclear Information System (INIS)

Blenkinsopp, S.A.; Sergy, G.; Doe, K.; Jackman, P.; Huybers, A.

1998-01-01

Environment Canada's Emergencies Science Division has established a program to develop a standard test method suitable for evaluating the toxicity of common sorbent materials. Sorbents are used to absorb or adsorb spilled oil and other hazardous materials. They vary widely in composition and packaging. They are often treated with oleophilic and hydrophobic compounds to improve performance and have been used in large quantities during oil spills. Until now, their potential toxicity has never been considered. Three tests have been evaluated to determine how appropriate they are in screening the toxicity of sorbents. Seven toxicity test recommendations for sorbents were presented. 7 refs., 3 tabs., 2 figs

Metabolic profiles show specific mitochondrial toxicities in vitro in myotube cells

International Nuclear Information System (INIS)

Xu Qiuwei; Vu, Heather; Liu Liping; Wang, Ting-Chuan; Schaefer, William H.

2011-01-01

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 β-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.

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

Computational systems biology and dose-response modeling in relation to new directions in toxicity testing.

Science.gov (United States)

Zhang, Qiang; Bhattacharya, Sudin; Andersen, Melvin E; Conolly, Rory B

2010-02-01

The new paradigm envisioned for toxicity testing in the 21st century advocates shifting from the current animal-based testing process to a combination of in vitro cell-based studies, high-throughput techniques, and in silico modeling. A strategic component of the vision is the adoption of the systems biology approach to acquire, analyze, and interpret toxicity pathway data. As key toxicity pathways are identified and their wiring details elucidated using traditional and high-throughput techniques, there is a pressing need to understand their qualitative and quantitative behaviors in response to perturbation by both physiological signals and exogenous stressors. The complexity of these molecular networks makes the task of understanding cellular responses merely by human intuition challenging, if not impossible. This process can be aided by mathematical modeling and computer simulation of the networks and their dynamic behaviors. A number of theoretical frameworks were developed in the last century for understanding dynamical systems in science and engineering disciplines. These frameworks, which include metabolic control analysis, biochemical systems theory, nonlinear dynamics, and control theory, can greatly facilitate the process of organizing, analyzing, and understanding toxicity pathways. Such analysis will require a comprehensive examination of the dynamic properties of "network motifs"--the basic building blocks of molecular circuits. Network motifs like feedback and feedforward loops appear repeatedly in various molecular circuits across cell types and enable vital cellular functions like homeostasis, all-or-none response, memory, and biological rhythm. These functional motifs and associated qualitative and quantitative properties are the predominant source of nonlinearities observed in cellular dose response data. Complex response behaviors can arise from toxicity pathways built upon combinations of network motifs. While the field of computational cell

In vitro and environmental toxicity of reduced graphene oxide as an additive in automotive lubricants.

Science.gov (United States)

Esquivel-Gaon, Margarita; Nguyen, Nhung H A; Sgroi, Mauro F; Pullini, Daniele; Gili, Flavia; Mangherini, Davide; Pruna, Alina Iuliana; Rosicka, Petra; Sevcu, Alena; Castagnola, Valentina

2018-04-05

Despite the ground-breaking potential of nanomaterials, their safe and sustainable incorporation into an array of industrial markets prompts a deep and clear understanding of their potential toxicity for both humans and the environment. Among the many materials with great potential, graphene has shown promise in a variety of applications; however, the impact of graphene based products on living systems remains poorly understood. In this paper, we illustrate that via exploiting the tribological properties of graphene nanosheets, we can successfully improve both the frictional behaviour and the anti-wear capacity of lubricant oil for mechanical transmission. By virtue of reducing friction and enhancing lubricant lifetimes, we can forecast a reduction in friction based energy loss, in addition to a decrease in the carbon footprint of vehicles. The aforementioned positive environmental impact is further strengthened considering the lack of acute toxicity found in our extensive in vitro investigation, in which both eukaryotic and prokaryotic cells were tested. Collectively, our body of work suggests that by the use of safe nanoadditives we could contribute to reducing the environmental impact of transportation and therein take a positive step towards a more sustainable automotive sector. The workflow proposed here for the evaluation of human and environmental toxicity will allow for the study of nanosized bare graphene material and can be broadly applied to the translation of graphene-based nanomaterials into the market.

Alginate based 3D hydrogels as an in vitro co-culture model platform for the toxicity screening of new chemical entities

International Nuclear Information System (INIS)

Lan, Shih-Feng; Starly, Binil

2011-01-01

Prediction of human response to potential therapeutic drugs is through conventional methods of in vitro cell culture assays and expensive in vivo animal testing. Alternatives to animal testing require sophisticated in vitro model systems that must replicate in vivo like function for reliable testing applications. Advancements in biomaterials have enabled the development of three-dimensional (3D) cell encapsulated hydrogels as in vitro drug screening tissue model systems. In this study, we have developed an in vitro platform to enable high density 3D culture of liver cells combined with a monolayer growth of target breast cancer cell line (MCF-7) in a static environment as a representative example of screening drug compounds for hepatotoxicity and drug efficacy. Alginate hydrogels encapsulated with serial cell densities of HepG2 cells (10 5 -10 8 cells/ml) are supported by a porous poly-carbonate disc platform and co-cultured with MCF-7 cells within standard cell culture plates during a 3 day study period. The clearance rates of drug transformation by HepG2 cells are measured using a coumarin based pro-drug. The platform was used to test for HepG2 cytotoxicity 50% (CT 50 ) using commercially available drugs which further correlated well with published in vivo LD 50 values. The developed test platform allowed us to evaluate drug dose concentrations to predict hepatotoxicity and its effect on the target cells. The in vitro 3D co-culture platform provides a scalable and flexible approach to test multiple-cell types in a hybrid setting within standard cell culture plates which may open up novel 3D in vitro culture techniques to screen new chemical entity compounds. - Graphical abstract: Display Omitted Highlights: → A porous support disc design to support the culture of desired cells in 3D hydrogels. → Demonstrated the co-culture of two cell types within standard cell-culture plates. → A scalable, low cost approach to toxicity screening involving multiple cell

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.

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

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.

The role of metabolism in diclofenac-induced intestinal toxicity in rat and human in vitro

NARCIS (Netherlands)

Niu, Xiaoyu; Makkinje, Miriam; de Graaf, Inge; Groothuis, Genoveva

The use of Diclofenac (DCF), a non-steroidal anti-inflammatory drug is associated with severe gastro-intestinal side-effects. The mechanisms of drug-induced intestinal toxicity are largely unknown due to the lack of in vitro models. In vivo rat studies suggested that reactive metabolites of DCF

Acute Inhalation Toxicity and Blood Absorption of 2,4-Dinitroanisole (DNAN) in Rats

Science.gov (United States)

2015-03-17

light/dark cycle. A certified pesticide -free rodent chow (Harlan Teklad ® , 8728C Certified Rodent Diet) and drinking quality water were available ad...respiration, toxicity, blood, concentration, alternative, welfare, method, model, in vitro, pain, distress, simulate, video , computer, replacement, refinement...Prevention, Pesticides , and Toxic Substances. December 2002. Health Effects Test Guidelines: OPPTS 870.1000, Acute Toxicity Testing - Background. EPA

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.

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...

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.

Preparation and toxicity evaluation of a novel nattokinase-tauroursodeoxycholate complex

Directory of Open Access Journals (Sweden)

Rui Feng

2018-03-01

Full Text Available Nattokinase (NK, which has been identified as a potent fibrinolytic protease, has remarkable potential in treatment of thrombolysis, and even has the ability to ameliorate chronic vein thrombosis. To reduce the hemorrhagic risk from an intravenous injection of NK, nattokinase-tauroursodeoxycholate (NK-TUDCA complex was prepared at different pH values and with different ratios of NK and TUDCA. When assessing survival time, survival state, tail injury, and the body weight of mice, it was found that the NK-TUDCA complex (NK: 10 kIU/ml; TUDCA: 10 mg/ml; pH 5.0 had a lower toxicity when administered at an NK dosage of 130 kIU/kg in the acute toxicity test and 13 kIU/kg in the repeated low-dose challenge. From the results of the in vitro thrombolytic test and characterization of NK-TUDCA, we speculated that the delayed release of NK-TUDCA might be the main cause of toxicity reduction by the complex. This study described the preparation of an NK complex with low toxicity following intravenous administration, which could be utilized for further clinical study of NK. Keywords: Nattokinase, Tauroursodeoxycholate, Complex, Toxicity test, In vitro thrombolytic test

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.

Corneal protection with high-molecular-weight hyaluronan against in vitro and in vivo sodium lauryl sulfate-induced toxic effects.

Science.gov (United States)

Pauloin, Thierry; Dutot, Mélody; Liang, Hong; Chavinier, Emilie; Warnet, Jean-Michel; Rat, Patrice

2009-10-01

The aim of this study was to investigate high-molecular-weight hyaluronan (HA-HMW) corneal protection against sodium lauryl sulfate (SLS)-induced toxic effects with in vitro and in vivo experimental approaches. In vitro experiments consisted of a human corneal epithelial cell line incubated with HA-HMW, rinsed, and incubated with SLS. Cell viability, oxidative stress, chromatin condensation, caspase-3, -8, -9, and P2X7 cell death receptor activation, interleukin-6, and interleukin-8 production were investigated. In vivo experiments consisted of 36 New Zealand white rabbits treated for 3 days, 3 times per day, with HA-HMW or phosphate-buffered salt solution. At day 4, eyes were treated with SLS. Clinical observation and in vivo confocal microscopy using the Rostock Cornea Module of the Heidelberg Retina Tomograph-II were performed to evaluate and to compare SLS-induced toxicity between eyes treated with HA-HMW and eyes treated with phosphate-buffered salt solution. In vitro data indicate that exposure of human corneal epithelial cells to HA-HMW significantly decreased SLS-induced oxidative stress, apoptosis, and inflammation cytokine production. In vivo data indicate that SLS cornea injuries, characterized by damaged corneal epithelium, damaged anterior stroma, and inflammatory infiltrations, were attenuated with HA-HMW treatment. A good correlation was seen between in vitro and in vivo findings showing that HA-HMW decreases SLS-induced toxic effects and protects cornea.

Rethinking developmental toxicity testing: Evolution or revolution?

NARCIS (Netherlands)

Scialli, Anthony R; Daston, George; Chen, Connie; Coder, Prägati S; Euling, Susan Y; Foreman, Jennifer; Hoberman, Alan M; Hui, Julia; Knudsen, Thomas; Makris, Susan L; Morford, LaRonda; Piersma, Aldert H; Stanislaus, Dinesh; Thompson, Kary E

2018-01-01

Current developmental toxicity testing adheres largely to protocols suggested in 1966 involving the administration of test compound to pregnant laboratory animals. After more than 50 years of embryo-fetal development testing, are we ready to consider a different approach to human developmental

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

International Nuclear Information System (INIS)

Theunissen, P.T.; Robinson, J.F.; Pennings, J.L.A.; Herwijnen, M.H. van; Kleinjans, J.C.S.; Piersma, A.H.

2012-01-01

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.

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.

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.

A chronic toxicity test protocol using Caridina nilotica (Decapoda ...

African Journals Online (AJOL)

Salinization of freshwater resources is an increasing global problem, yet there is a paucity of chronic salinity tolerance data linked to very few chronic toxicity test protocols. This research aimed to generate a chronic toxicity test protocol and protective salinity tolerance data for the indigenous South African freshwater shrimp ...

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.

In vitro toxicity of zinc oxide nanoparticles: a review

International Nuclear Information System (INIS)

Pandurangan, Muthuraman; Kim, Doo Hwan

2015-01-01

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 2+ ] level. The mechanism for increased intracellular [Zn 2+ ] level and ZnO nanoparticles dissolution in the medium is still unclear. Cytotoxicity, increased oxidative stress, increased intracellular [Ca 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

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.

The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity.

Science.gov (United States)

Heggers, John P; Cottingham, John; Gusman, Jean; Reagor, Lee; McCoy, Lana; Carino, Edith; Cox, Robert; Zhao, Jian-Gang; Reagor, Lana

2002-06-01

Recent testimonials report grapefruit-seed extract, or GSE (Citricidal) to be effective against more than 800 bacterial and viral strains, 100 strains of fungus, and a large number of single and multicelled parasites. This study investigated GSE for antibacterial activity at varying time intervals and concentration levels and tissue toxicity at varying concentrations in an effort to determine if a concentration existed that was both microbicidal and nontoxic and in what period of time. Gram-negative and gram-positive isolates were introduced into graduated dilutions of GSE (twofold concentrations ranging from 1:1, through 1:512) for determination of bacterial activity. In vitro assays with human skin fibroblast cells were also performed at the same dilutions to determine toxicity. These tests indicated that from the 1:1 through the 1:128 concentrations, GSE remained toxic as well as bactericidal. However, test results indicated that at the 1:512 dilution, GSE remained bactericidal, but completely nontoxic. The initial data shows GSE to have antimicrobial properties against a wide range of gram-negative and gram-positive organisms at dilutions found to be safe. With the aid of scanning transmission electron microscopy (STEM), the mechanism of GSE's antibacterial activity was revealed. It was evident that GSE disrupts the bacterial membrane and liberates the cytoplasmic contents within 15 minutes after contact even at more dilute concentrations.

In vitro evaluation of the toxic effects and endocrine disrupting potential of oil sands processed water and naphthenic acids

Energy Technology Data Exchange (ETDEWEB)

Zhang, X.; Wiseman, S.; Higley, E.; Jones, P.D.; Hecker, M.; Giesy, J.P. [Saskatchewan Univ., Saskatoon, SK (Canada); Gamel El Din, M.; Martin, J.W. [Alberta Univ., Edmonton, AB (Canada)

2009-07-01

Naphthenic acids (NAs) are the primary toxic constituents of oil sands process-affected waters (OSPW). This presentation reported on a series of in vitro studies that were initiated to evaluate potential endocrine modulating effects of OSPW and their constituent NAs. The H295R steroidogenesis bioassay was used to examine the impact of OSPW and NA on 52 steroidogenesis. In particular, dose-response and time course studies were conducted to evaluate the impact of OSPW and NAs on testosterone and estradiol production. Aromatase activity and transcript abundance of the key 11 steroidogenic enzymes were also quantified to complement analysis of hormone levels. The MVLN trans-activation assay was used to test the estrogenicity/anti-estrogenicity of OSPW and NAs. In vitro cell viability and apoptosis (live-dead) caused by OSPW and NAs was quantified by the MTS reduction and caspase-3/7 activity in H295R and MVLN cells.

The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test

International Nuclear Information System (INIS)

Davies, N.A.Nicola A.; Hodson, M.E.Mark E.; Black, S.Stuart

2003-01-01

Timing of lead addition and worms to soil affects the response of the worms to soil affects the response of the worms to lead. - Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC 50 s for 14 and 28 days were 5311 and 5395 μg Pb g -1 soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 μg Pb g -1 soil . The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 μg g -1 soil accumulated lead at a faster rate (3.16 μg Pb g -1 tissue day -1 ) than those in the 3000 μg g -1 soil (2.21 μg Pb g -1 tissue day -1 ). The third experiment was a timed experiment with worms cultivated in soil containing 7000 μg Pb g -1 soil . Soil and lead nitrate solution were mixed and stored at 20 deg. C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration

Toxicity of penicillic acid for rat alveolar macrophages in vitro

International Nuclear Information System (INIS)

Sorenson, W.G.; Simpson, J.

1985-01-01

Penicillic acid (PA) is a polyketide mycotoxin produced by several species of Aspergillus and Penicillium. This mycotoxin is toxic in experimental animals and has also been reported to be carcinogenic. The cytotoxicity of penicillic acid was studied in rat albeolar macrophages (AM) in vitro. The effects of penicillic acid on membrane integrity were studied by measuring cell volume changes and 51 Cr release. There was a significant decrease in adenosine triphosphate (ATP) in cell cultures exposed to 1.0 mM penicillic acid for 4 hr. Inhibition of the incorporation of [ 3 H]leucine into protein was both dose- and time-dependent and protein synthesis was inhibited significantly after 2 hr exposure to ≥0.1 mM penicillic acid. RNA synthesis was inhibited to a lesser extent than protein synthesis. There was significant inhibition of phagocytosis after 2 hr exposure at ≥0.3 mM penicillic acid and the ED 50 for phagocytosis was 0.09 mM. Thus phagocytosis was more sensitive to the toxic effects of penicillic acid than any other cellular process studied. The data suggest the possibility of a respiratory hazard to agricultural workers exposed to contaminated grain

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.

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 ...

Development of complex-shaped liver multicellular spheroids as a human-based model for nanoparticle toxicity assessment in vitro

Energy Technology Data Exchange (ETDEWEB)

Dubiak-Szepietowska, Monika, E-mail: Monika.Dubiak-Szepietowska@fh-jena.de [Department of Medical Engineering and Biotechnology, Ernst-Abbe-University of Applied Sciences Jena, Carl-Zeiss Promenade 2, 07745 Jena (Germany); Karczmarczyk, Aleksandra [Department of Medical Engineering and Biotechnology, Ernst-Abbe-University of Applied Sciences Jena, Carl-Zeiss Promenade 2, 07745 Jena (Germany); Jönsson-Niedziółka, Martin [Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warszawa (Poland); Winckler, Thomas [Institute of Pharmacy, Friedrich Schiller University Jena, Semmelweissstraße 10, 07743 Jena (Germany); Feller, Karl-Heinz [Department of Medical Engineering and Biotechnology, Ernst-Abbe-University of Applied Sciences Jena, Carl-Zeiss Promenade 2, 07745 Jena (Germany)

2016-03-01

The emergence of human-based models is incontestably required for the study of complex physiological pathways and validation of reliable in vitro methods as alternative for in vivo studies in experimental animals for toxicity assessment. With this objective, we have developed and tested three dimensional environments for cells using different types of hydrogels including transglutaminase-cross-linked gelatin, collagen type I, and growth-factor depleted Matrigel. Cells grown in Matrigel exhibited the greatest cell proliferation and spheroid diameter. Moreover, analysis of urea and albumin biosynthesis revealed that the created system allowed the immortalized liver cell line HepG2 to re-establish normal hepatocyte-like properties which were not observed under the conditions of conventional cell cultures. This study presents a scalable technology for production of complex-shaped liver multicellular spheroids as a system which improves the predictive value of cell-based assays for safety and risk assessment. The time- and dose-dependent toxicity of nanoparticles demonstrates a higher cytotoxic effect when HepG2 cells grown as monolayer than embedded in hydrogels. The experimental setup provided evidence that the cell environment has significant influence on cell sensitivity and that liver spheroid is a useful and novel tool to examine nanoparticle dosing effect even at the level of in vitro studies. Therefore, this system can be applied to a wide variety of potentially hostile compounds in basic screening to provide initial warning of adverse effects and trigger subsequent analysis and remedial actions. - Highlights: • Comparison of HepG2 cells growth in Matrigel, Collagen I gel and gelatin gel. • Examination of nanoparticles (NP) dosing effect at the level of in vitro studies. • Influence of the cell culture media composition on the cytotoxic effect of NP.

Development of complex-shaped liver multicellular spheroids as a human-based model for nanoparticle toxicity assessment in vitro

International Nuclear Information System (INIS)

Dubiak-Szepietowska, Monika; Karczmarczyk, Aleksandra; Jönsson-Niedziółka, Martin; Winckler, Thomas; Feller, Karl-Heinz

2016-01-01

The emergence of human-based models is incontestably required for the study of complex physiological pathways and validation of reliable in vitro methods as alternative for in vivo studies in experimental animals for toxicity assessment. With this objective, we have developed and tested three dimensional environments for cells using different types of hydrogels including transglutaminase-cross-linked gelatin, collagen type I, and growth-factor depleted Matrigel. Cells grown in Matrigel exhibited the greatest cell proliferation and spheroid diameter. Moreover, analysis of urea and albumin biosynthesis revealed that the created system allowed the immortalized liver cell line HepG2 to re-establish normal hepatocyte-like properties which were not observed under the conditions of conventional cell cultures. This study presents a scalable technology for production of complex-shaped liver multicellular spheroids as a system which improves the predictive value of cell-based assays for safety and risk assessment. The time- and dose-dependent toxicity of nanoparticles demonstrates a higher cytotoxic effect when HepG2 cells grown as monolayer than embedded in hydrogels. The experimental setup provided evidence that the cell environment has significant influence on cell sensitivity and that liver spheroid is a useful and novel tool to examine nanoparticle dosing effect even at the level of in vitro studies. Therefore, this system can be applied to a wide variety of potentially hostile compounds in basic screening to provide initial warning of adverse effects and trigger subsequent analysis and remedial actions. - Highlights: • Comparison of HepG2 cells growth in Matrigel, Collagen I gel and gelatin gel. • Examination of nanoparticles (NP) dosing effect at the level of in vitro studies. • Influence of the cell culture media composition on the cytotoxic effect of NP.

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

2018-02-01

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 as a result of their high hydrophobicity and low toxicity thresholds, which often fall below the analytical methods detection limits (MDLs). 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 the present study, we quantified toxicity loss during storage and testing, using both natural and synthetic water, and presented a tool to enhance toxic signal strength for improved sensitivity of H. azteca toxicity tests. The average half-life during storage in low-density polyethylene (LDPE) cubitainers (Fisher Scientific) at 4 °C of 5 pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, cyfluthrin, and 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. Environ Toxicol Chem 2018;37:462-472. © 2017 SETAC. © 2017 SETAC.

Exposure to Inorganic Nanoparticles: Routes of Entry, Immune Response, Biodistribution and In Vitro/In Vivo Toxicity Evaluation

Directory of Open Access Journals (Sweden)

Valeria De Matteis

2017-10-01

Full Text Available The development of different kinds of nanoparticles, showing different physico-chemical properties, has fostered their large use in many fields, including medicine. As a consequence, inorganic nanoparticles (e.g., metals or semiconductors, have raised issues about their potential toxicity. The scientific community is investigating the toxicity mechanisms of these materials, in vitro and in vivo, in order to provide accurate references concerning their use. This review will give the readers a thorough exploration on the entry mechanisms of inorganic nanoparticles in the human body, such as titanium dioxide nanoparticles (TiO2NPs, silicon dioxide nanoparticles (SiO2NPs, zinc oxide nanoparticles (ZnONPs, silver nanoparticles (AgNPs, gold nanoparticles (AuNPs and quantum dots (QDsNPs. In addition, biodistribution, the current trends and novelties of in vitro and in vivo toxicology studies will be discussed, with a particular focus on immune response.

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.

Toxicity testing of polymer materials for dialysis equipment: reconsidering in vivo testing.

Science.gov (United States)

Sauer, U G; Liebsch, M; Kolar, R

2000-01-01

In fulfilment of the aims of the European Union Biocidal Directive (Directive 98/8/EC), Technical Guidance Documents are currently being compiled. Part I of these Technical Guidance Documents covers data requirements for active substances and biocidal products. The Three Rs principle has been applied in certain parts of the toxicity and ecotoxicity testing scheme for pesticides, such as testing for acute oral toxicity, skin and eye irritation, skin sensitisation, and dermal absorption. Further recommendations on how to proceed with regard to the continuing replacement, reduction and refinement of animal experiments in this field of regulatory testing are included for consideration. In this context, besides stressing the necessity to validate and accept further alternatives, emphasis is placed on providing the possibility of waiving unnecessary tests and on the continuous evaluation of whether certain tests are needed at all. 2000 FRAME.

In vitro evaluation of matrix metalloproteinases as predictive testing for nickel, a model sensitizing agent

International Nuclear Information System (INIS)

Lamberti, Monica; Perfetto, Brunella; Costabile, Teresa; Canozo, Nunzia; Baroni, Adone; Liotti, Francesco; Sannolo, Nicola; Giuliano, Mariateresa

2004-01-01

The identification of potential damage due to chemical exposure in the workplace is a major health and regulatory concern. Traditional tests that measure both sensitization and elicitation responses require the use of animals. An alternative to this widespread use of experimental animals could have a crucial impact on risk assessment, especially for the preliminary screening of new molecules. We developed an in vitro model for the screening of potential toxic compounds. Human keratinocytes (HaCat) were used as target cells while matrix metalloproteinases (MMP) were selected as responders because they are key enzymes involved in extracellular matrix (ECM) degradation in physiological and pathological conditions. Chemical exposure was performed using nickel sulphate as a positive tester. Nickel contact induced upregulation of MMP-2 and IL-8 mRNA production. Molecular activation occurred even at very low nickel concentrations even though no phenotypic changes were observed. MMP-9 accumulation was found in the medium of treated cells with respect to controls. These observations led to the hypothesis that even minimal exposure can accumulate transcriptional activity resulting in long-term clinical signs after contact. Our simple in vitro model can be applied as a useful preliminary complement to the animal studies to screen the effects of new potential toxic compounds

Sediment toxicity testing with the amphipod Ampelisca abdita in Calcasieu Estuary, Louisiana

Science.gov (United States)

Redmond, M.S.; Crocker, P.A.; McKenna, K.M.; Petrocelli, E.A.; Scott, K.J.; Demas, C.R.

1996-01-01

Discharges from chemical and petrochemical manufacturing facilities have contaminated portions of Louisiana's Calcasieu River estuary with a variety of organic and inorganic contaminants. As part of a special study, sediment toxicity testing was conducted to assess potential impact to the benthic community. Ten-day flow-through sediment toxicity tests with the amphipod Ampelisca abdita revealed significant toxicity at 68% (26 of 38) of the stations tested. A. abdita mortality was highest in the effluent-dominated bayous, which are tributaries to the Calcasieu River. Mortality was correlated with total heavy metal and total organic compound concentrations in the sediments. Ancillary experiments showed that sediment interstitial water salinity as low as 2.5 o/o-o did not significantly affect A. abdita's, response in the flow-through system; sediment storage for 7 weeks at 4??C did not significantly affect toxicity. Sediment toxicity to A. abdita was more prevalent than receiving water toxicity using three short-term chronic bioassays. Results suggest that toxicity testing using this amphipod is a valuable tool when assessing sediments containing complex contaminant mixtures and for assessing effects of pollutant loading over time. In conjunction with chemical analyses, the testing indicated that the effluent-dominated, brackish bayous (Bayou d'Inde and Bayou Verdine) were the portions of the estuary most impacted by toxicity.

An in vitro assay for compounds toxic to rumen protozoa

International Nuclear Information System (INIS)

Campbell, A.J.; Cumming, G.J.; Graham, C.A.; Leng, R.A.

1982-01-01

The viability of protozoa in whole rumen fluid was assessed by measuring the incorporation of Me- 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. (auth)

A combined approach to investigate the toxicity of an industrial landfill's leachate: Chemical analyses, risk assessment and in vitro assays

International Nuclear Information System (INIS)

Baderna, D.; Maggioni, S.; Boriani, E.; Gemma, S.; Molteni, M.; Lombardo, A.; Colombo, A.; Bordonali, S.; Rotella, G.; Lodi, M.; Benfenati, E.

2011-01-01

Solid wastes constitute an important and emerging problem. Landfills are still one of the most common ways to manage waste disposal. The risk assessment of pollutants from landfills is becoming a major environmental issue in Europe, due to the large number of sites and to the importance of groundwater protection. Furthermore, there is lack of knowledge for the environmental, ecotoxicological and toxicological characteristics of most contaminants contained into landfill leacheates. Understanding leachate composition and creating an integrated strategy for risk assessment are currently needed to correctly face the landfill issues and to make projections on the long-term impacts of a landfill, with particular attention to the estimation of possible adverse effects on human health and ecosystem. In the present study, we propose an integrated strategy to evaluate the toxicity of the leachate using chemical analyses, risk assessment guidelines and in vitro assays using the hepatoma HepG2 cells as a model. The approach was applied on a real case study: an industrial waste landfill in northern Italy for which data on the presence of leachate contaminants are available from the last 11 years. Results from our ecological risk models suggest important toxic effects on freshwater fish and small rodents, mainly due to ammonia and inorganic constituents. Our results from in vitro data show an inhibition of cell proliferation by leachate at low doses and cytotoxic effect at high doses after 48 h of exposure. - Research highlights: → We study the toxicity of leachate from a non-hazardous industrial waste landfill. → We perform chemical analyses, risk assessments and in vitro assays on HepG2 cells. → Risk models suggest toxic effects due to ammonia and inorganic constituents. → In vitro assays show that leachate inhibits cell proliferation at low doses. → Leachate can induce cytotoxic effects on HepG2 cells at high doses.

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.

Differences between co-cultures and monocultures in testing the toxicity of particulate matter derived from log wood and pellet combustion

Science.gov (United States)

Happo, Mikko S.; Rönkkö, Teemu J.; Orasche, Jürgen; Jokiniemi, Jorma; Kortelainen, Miika; Tissari, Jarkko; Zimmermann, Ralf; Hirvonen, Maija-Riitta; Jalava, Pasi I.

2018-01-01

Background In vitro studies with monocultures of human alveolar cells shed deeper knowledge on the cellular mechanisms by which particulate matter (PM) causes toxicity, but cannot account for mitigating or aggravating effects of cell-cell interactions on PM toxicity. Methods We assessed inflammation, oxidative stress as well as cytotoxic and genotoxic effects induced by PM from the combustion of different types of wood logs and softwood pellets in three cell culture setups: two monocultures of either human macrophage-like cells or human alveolar epithelial cells, and a co-culture of these two cell lines. The adverse effects of the PM samples were compared between these setups. Results We detected clear differences in the endpoints between the mono- and co-cultures. Inflammatory responses were more diverse in the macrophage monoculture and the co-culture compared to the epithelial cells where only an increase of IL-8 was detected. The production of reactive oxygen species was the highest in epithelial cells and macrophages seemed to have protective effects against oxidative stress from the PM samples. With no metabolically active cells at the highest doses, the cytotoxic effects of the PM samples from the wood log combustion were far more pronounced in the macrophages and the co-culture than in the epithelial cells. All samples caused DNA damage in macrophages, whereas only beech and spruce log combustion samples caused DNA damage in epithelial cells. The organic content of the samples was mainly associated with cytotoxicity and DNA damage, while the metal content of the samples correlated with the induction of inflammatory responses. Conclusions All of the tested PM samples induce adverse effects and the chemical composition of the samples determines which pathway of toxicity is induced. In vitro testing of the toxicity of combustion-derived PM in monocultures of one cell line, however, is inadequate to account for all the possible pathways of toxicity. PMID

An evaluation of the whole effluent toxicity test method

International Nuclear Information System (INIS)

Osteen, D.V.

1999-01-01

Whole effluent toxicity (WET) testing has become increasingly more important to the Environmental Protection Agency (EPA) and the States in the permitting of wastewater discharges from industry and municipalities. The primary purpose of the WET test is to protect aquatic life by predicting the effect of an effluent on the receiving stream. However, there are both scientific and regulatory concerns that using WET tests to regulate industrial effluents may result in either false positives and/or false negatives. In order to realistically predict the effect of an effluent on the receiving stream, the test should be as representative as possible of the conditions in the receiving stream. Studies (Rand and Petrocelli 1985) suggested several criteria for an ideal aquatic toxicity test organism, one of which is that the organism be indigenous to, or representative of, the ecosystem receiving the effluent. The other component needed in the development of a predictive test is the use of the receiving stream water or similar synthetic water as the control and dilution water in the test method. Use of an indigenous species and receiving water in the test should help reduce the variability in the method and allow the test to predict the effect of the effluent on the receiving stream. The experience with toxicity testing at the Savannah River Site (SRS) has yielded inconclusive data because of the inconsistency and unreliability of the results. The SRS contention is that the WET method in its present form does not adequately mimic actual biological/chemical conditions of the receiving streams and is neither reasonable nor accurate. This paper discusses the rationale for such a position by SRS on toxicity testing in terms of historical permitting requirements, outfall effluent test results, standard test method evaluation, scientific review of alternate test species, and concerns over the test method expressed by other organizations. This paper presents the Savannah River Site

In vitro testing of thiolated poly(aspartic acid) from ophthalmic formulation aspects.

Science.gov (United States)

Budai-Szű Cs, Mária; Horvát, Gabriella; Gyarmati, Benjámin; Szilágyi, Barnabás Áron; Szilágyi, András; Csihi, Tímea; Berkó, Szilvia; Szabó-Révész, Piroska; Mori, Michela; Sandri, Giuseppina; Bonferoni, Maria Cristina; Caramella, Carla; Csányi, Erzsébet

2016-08-01

Ocular drug delivery formulations must meet anatomical, biopharmaceutical, patient-driven and regulatory requirements. Mucoadhesive polymers can serve as a better alternative to currently available ophthalmic formulations by providing improved bioavailability. If all requirements are addressed, a polymeric formulation resembling the tear film of the eye might be the best solution. The optimum formulation must not have high osmotic activity, should provide appropriate surface tension, pH and refractive index, must be non-toxic and should be transparent and mucoadhesive. We would like to highlight the importance of in vitro polymer testing from a pharmaceutical aspect. We, therefore, carried out physical-chemical investigations to verify the suitability of certain systems for ophthalmic formulations. In this work, in situ gelling, mucoadhesive thiolated poly(aspartic acid)s were tested from ophthalmic formulation aspects. The results of preformulation measurements indicate that these polymers can be used as potential carriers in ophthalmic drug delivery.

Developmental toxicity assessment of common excipients using a stem cell-based in vitro morphogenesis model.

Science.gov (United States)

Yuan, Chloe J; Marikawa, Yusuke

2017-11-01

Various chemical compounds can inflict developmental toxicity when sufficiently high concentrations are exposed to embryos at the critical stages of development. Excipients, such as coloring agents and preservatives, are pharmacologically inactive ingredients that are included in various medications, foods, and cosmetics. However, concentrations that may adversely affect embryo development are largely unknown for most excipients. Here, the lowest observed adverse effect level (LOAEL) to inflict developmental toxicity was assessed for three coloring agents (allura red, brilliant blue, and tartrazine) and three preservatives (butylated hydroxyanisole, metabisulfite, and methylparaben). Adverse impact of a compound exposure was determined using the stem cell-based in vitro morphogenesis model, in which three-dimensional cell aggregates, or embryoid bodies (EBs), recapitulate embryonic processes of body axis elongation and patterning. LOAEL to impair EB morphogenesis was 200 μM for methylparaben, 400 μM for butylated hydroxyanisole, 600 μM for allura red and brilliant blue, and 1000 μM for metabisulfite. Gene expression analyses of excipient-treated EBs revealed that butylated hydroxyanisole and methylparaben significantly altered profiles of developmental regulators involved in axial elongation and patterning of the body. The present study may provide a novel in vitro approach to investigate potential developmental toxicity of common excipients with mechanistic insights. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

International Nuclear Information System (INIS)

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.

2015-01-01

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

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

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

Controlling silver nanoparticle exposure in algal toxicity testing - A matter of timing

DEFF Research Database (Denmark)

Sørensen, Sara Nørgaard; Baun, Anders

2015-01-01

) in a standard algal growth inhibition test (ISO 8692:2004) for 48 h and a short-term (2 h) 14C-assimilation test. For AgNO3, similar responses were obtained in the two tests, whereas freshly prepared suspensions of citrate stabilized AgNPs were less toxic in the 2-h tests compared to the 48-h tests. The 2-h...... test was found applicable for dissolved silver, but yielded non-monotonous concentration–response relationships and poor reproducibility for freshly prepared AgNP suspensions. However, when aging AgNPs in algal medium 24 h prior to testing, clear concentration–response patterns emerged...... and reproducibility increased. Prolonged aging to 48 h increased toxicity in the 2-h tests whereas aging beyond 48 h reduced toxicity. Our results demonstrate that the outcome of algal toxicity testing of AgNPs is highly influenced not only by the test duration, but also by the time passed from the moment Ag...

Sensitivity of submersed freshwater macrophytes and endpoints in laboratory toxicity tests

International Nuclear Information System (INIS)

Arts, Gertie H.P.; Belgers, J. Dick M.; Hoekzema, Conny H.; Thissen, Jac T.N.M.

2008-01-01

The toxicological sensitivity and variability of a range of macrophyte endpoints were statistically tested with data from chronic, non-axenic, macrophyte toxicity tests. Five submersed freshwater macrophytes, four pesticides/biocides and 13 endpoints were included in the statistical analyses. Root endpoints, reflecting root growth, were most sensitive in the toxicity tests, while endpoints relating to biomass, growth and shoot length were less sensitive. The endpoints with the lowest coefficients of variation were not necessarily the endpoints, which were toxicologically most sensitive. Differences in sensitivity were in the range of 10-1000 for different macrophyte-specific endpoints. No macrophyte species was consistently the most sensitive. Criteria to select endpoints in macrophyte toxicity tests should include toxicological sensitivity, variance and ecological relevance. Hence, macrophyte toxicity tests should comprise an array of endpoints, including very sensitive endpoints like those relating to root growth. - A range of endpoints is more representative of macrophyte fitness than biomass and growth only

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.

Prediction of toxicity and comparison of alternatives using WebTEST (Web-services Toxicity Estimation Software Tool)

Science.gov (United States)

A Java-based web service is being developed within the US EPA’s Chemistry Dashboard to provide real time estimates of toxicity values and physical properties. WebTEST can generate toxicity predictions directly from a simple URL which includes the endpoint, QSAR method, and ...

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.

Predictive acute toxicity tests with pesticides.

Science.gov (United States)

Brown, V K

1983-01-01

By definition pesticides are biocidal products and this implies a probability that pesticides may be acutely toxic to species other than the designated target species. The ways in which pesticides are manufactured, formulated, packaged, distributed and used necessitates a potential for the exposure of non-target species although the technology exists to minimize adventitious exposure. The occurrence of deliberate exposure of non-target species due to the misuse of pesticides is known to happen. The array of predictive acute toxicity tests carried out on pesticides and involving the use of laboratory animals can be justified as providing data on which hazard assessment can be based. This paper addresses the justification and rationale of this statement.

Repeated dose 90-day oral toxicity test of G-7% NANA in rats: An application of new criterion for toxicity determination to test article-induced changes.

Science.gov (United States)

Heo, Hye Seon; An, MinJi; Lee, Ji Sun; Kim, Hee Kyong; Park, Yeong-Chul

2018-06-01

G-7% NANA is N-acetylneuraminic acid(NANA) containing 7% sialic acid isolated from glycomacropeptide (GMP), a compound of milk. Since NANA is likely to have immunotoxicity, the need to ensure safety for long-term administration has been raised. In this study, a 90-day repeated oral dose toxicity test was performed in rats using G-7% NANA in the dosages of 0, 1250, 2500 and 5000 mg/kg/day.A toxicity determination criterion based on the significant change caused by the administration of the substancewas developed for estimating NOEL, NOAEL and LOAELapplied to this study. When analyzing the immunological markers, no significant changes were observed, even if other significant changes were observed in the high dose group. In accordance with the toxicity determination criterion developed, the NOEL in male and female has been determined as 2500 mg/kg/day, and the NOAEL in females has been determined as 5000 mg/kg/day. The toxicity determination criterion, applied for the first time in the repeated dose toxicity tests, could provide a basis for distinguishing NOEL and NOAEL more clearly; nevertheless, the toxicity determination criterion needs to be supplemented by adding differentiating adverse effects and non-adverse effects based on more experiences of the repeated dose toxicity tests. Copyright © 2018 Elsevier Inc. All rights reserved.

Radiosensitization in vitro and in vivo by 3-nitrotriazoles

International Nuclear Information System (INIS)

Shibamoto, Y.; Sakano, K.; Kimura, R.; Nishidai, T.; Nishimoto, S.; Ono, K.; Kagiya, T.; Abe, M.

1986-01-01

A series of 3-nitro-1,2,4-triazole derivatives bearing various types of side chain (R) at the N1-position (AK-2000 series) were synthesized and their radiosensitizing effect and toxicity in vitro and in vivo were investigated, in comparison with those of Misonidazole (MISO), SR-2508, and RSU-1069. Of the fifteen 3-nitrotriazoles tested, all had sensitizing effects in vitro on hypoxic V79 cells. Also, all but one had definite effects on solid EMT6/KU and SCCVII tumors in vivo. For many of the triazole compounds, the degree of radiosensitization in vitro and in vivo appeared identical. However, they were generally less efficient, both in vitro and in vivo, than the corresponding 2-nitroimidazoles, whereas their aerobic cytotoxicity and toxicity to mice (LD50/7) were comparable to those of the 2-nitroimidazoles. Considering the sensitizing effect and toxicity, AK-2123 (R = CH 2 CONHC 2 H 4 OCH 3 ) may be as useful as MISO, but none of the triazoles have been proved to be superior to SR-2508

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

NARCIS (Netherlands)

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

2017-01-01

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

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

NARCIS (Netherlands)

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

2017-01-01

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

Assessment of an in vitro model of human cells to evaluate the toxic and irritating potential of chemical compounds

Directory of Open Access Journals (Sweden)

M. Catalano

2011-01-01

Full Text Available We attempted to induce differentation in unidifferentiated NCTC2544 human keratinocyte line, by exposure to ZnSO4 and CaCl2. Analysis of specific markers, transglutaminase I, involucrin and loricrin, show that basal NCTC2544 (BL reached spinous- (SL and granular-like (GL phenotypes. BL-, SI- and GL- NCTC were exposed to SDS, as irritant stimulus and Neutral red uptake (NRU and MTT cytoxicity tests evidenced a relatively higher toxicity in SL- and GL cells on lysosomes respect to mitochondria. ILIα cytokine was monitored as early inflammation marker. The complex of data provides evidence for the suitability of our in vitro model to the analysis of cytotoxic/biological effects of topically applied exogenous compounds.

Toxicity of geraniol solution in vitro to the poultry red mite, Dermanyssus gallinae

Directory of Open Access Journals (Sweden)

George D.R.

2009-12-01

Full Text Available Geraniol is a bioactive component found in Palmarosa essential oil which has previously demonstrated good repellence to cattle ticks, mosquitoes and sand flies. The toxicity of geraniol to Dermanyssus gallinae, the most economically deleterious ectoparasite of laying hens in Europe, was studied in vitro in the laboratory. Exposure of D. gallinae to 0.5, 1 and 2% concentrations of geraniol (equating approximately to 0.02, 0.04 and 0.07 mg/cm2 geraniol, respectively over a period of 24 hours resulted in 100% mortality of D. gallinae at all doses used.

Improvement in Shrimp Hatchery Procedures for Toxicity Tests

International Nuclear Information System (INIS)

Nor Azizah Marsiddi; Fazliana Mohd Saaya; Anee Suryani Sued

2015-01-01

Toxicity testing of brine shrimp Artemia salina Brine shrimp lethality assay is a screening test to determine half the dose mortality (LC50) for its shrimp given certain herbal extract at a concentration tested. The shrimp child mortality half a dose indicator to determine level of toxicity before further testing done on animal cell culture and animal experiments also on the mouse. The use of new hardware, namely Artemio 1 has increased its shrimp production at a rate that more and faster than the use of the black box hatching previously taken from the method by Solis, 1993. brine shrimp eggs from Artemio mix also easier to use because it contains egg and sea salt have been ready mixed for use in experiments. In conclusion, this method improvements help increase the number of offspring produced shrimp and produce experimental method easier than previous methods. (author)

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.

Dynamic changes in energy metabolism upon embryonic stem cell differentiation support developmental toxicant identification

NARCIS (Netherlands)

Dartel, van D.A.M.; Schulpen, S.H.; Theunissen, P.T.; Bunschoten, A.; Piersma, A.H.; Keijer, J.

2014-01-01

Embryonic stem cells (ESC) are widely used to study embryonic development and to identify developmental toxicants. Particularly, the embryonic stem cell test (EST) is well known as in vitro model to identify developmental toxicants. Although it is clear that energy metabolism plays a crucial role in

An early developmental vertebrate model for nanomaterial safety: bridging cell-based and mammalian toxicity assessment.

Science.gov (United States)

Webster, Carl A; Di Silvio, Desire; Devarajan, Aarthi; Bigini, Paolo; Micotti, Edoardo; Giudice, Chiara; Salmona, Mario; Wheeler, Grant N; Sherwood, Victoria; Bombelli, Francesca Baldelli

2016-03-01

With the rise in production of nanoparticles (NPs) for an ever-increasing number of applications, there is an urgent need to efficiently assess their potential toxicity. We propose a NP hazard assessment protocol that combines mammalian cytotoxicity data with embryonic vertebrate abnormality scoring to determine an overall toxicity index. We observed that, after exposure to a range of NPs, Xenopus phenotypic scoring showed a strong correlation with cell based in vitro assays. Magnetite-cored NPs, negative for toxicity in vitro and Xenopus, were further confirmed as nontoxic in mice. The results highlight the potential of Xenopus embryo analysis as a fast screening approach for toxicity assessment of NPs, which could be introduced for the routine testing of nanomaterials.

Nanoparticulate-induced toxicity and related mechanism in vitro and in vivo

International Nuclear Information System (INIS)

Kim, Hye Won; Ahn, Eun-Kyung; Jee, Bo Keun; Yoon, Hyoung-Kyu; Lee, Kweon Haeng; Lim, Young

2009-01-01

In urban areas, the quantity of exhaust particles from vehicle emissions is tremendous and has been regarded as the main contributor to particulate matter (PM) pollution. Recently, the nano-sized PM on public health has begun to raise the attention. The increased toxicity of nanoparticulate can be largely explained by their small size, high airborne concentration, extensive surface area and high content of organic carbon and transition metals. We have attempted to address the toxicity of nano sized-particlulate matter by comparing various particulates including micro-SiO 2 (mSiO 2 ), nano-SiO 2 (nSiO 2 ), micro-TiO 2 (mTiO 2 ), and nano-TiO 2 (nTiO 2 ) in RAW264.7 cells and in vivo. The cell viability of all particulates decreased dose dependently. 24-h incubation with nSiO2 demonstrated apoptosis in RAW264.7 using Annexin-V binding immunofluorescent microscopy, but not in any other particulates. In vivo, cytotoxicity of nanosized was higher than micro-sized particulates. As higher the concentration of particulates, the more pulmonary injury and neutrophilic infiltration were observed in nano-sized than micro-sized particulates, respectively. Particularly, 5.0 mg/kg of mTiO 2 never shows any increase of neutrophile even with high cellularity of total cells and macrophages. From these results, we suggested that particulate-induced respiratory toxicity be influenced by component, size, and dose of particulates including the characteristic nature of the target cells in vitro and in vivo.

Comparative in vitro toxicity assessment of perfluorinated carboxylic acids.

Science.gov (United States)

Mahapatra, Cecon T; Damayanti, Nur P; Guffey, Samuel C; Serafin, Jennifer S; Irudayaraj, Joseph; Sepúlveda, Maria S

2017-06-01

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are synthetic fluorinated compounds that are highly bioaccumulative and persistent organic pollutants. Perfluorooctanoic acid (PFOA), an eight-carbon chain perfluorinated carboxylic acid, was used heavily for the production of fluoropolymers, but concerns have led to its replacement by shorter carbon chain homologues such as perfluorohexanoic acid (PFHxA) and perfluorobutanoic acid (PFBA). However, limited toxicity data exist for these substitutes. We evaluated the toxicity of PFOA, PFHxA and PFBA on a zebrafish liver cell line and investigated the effects of exposure on cell metabolism. Gross toxicity after 96 h of exposure was highest for PFOA and PFO - , while PFHxA and PFBA exhibited lower toxicity. Although the structural similarity of these compounds to fatty acids suggests the possibility of interference with the transport and metabolism of lipids, we could not detect any differential expression of peroxisome proliferator-activated receptor (ppar-α, -β and -γ), fabp3 and crot genes after 96 h exposure to up to 10 ppm of the test compounds. However, we observed localized lipid droplet accumulation only in PFBA-exposed cells. To study the effects of these compounds on cell metabolism, we conducted fluorescence lifetime imaging microscopy using naturally fluorescent biomarkers, NADH and FAD. The fluorescence lifetimes of NADH and FAD and the bound/free ratio of each of these coenzymes decreased in a dose- and carbon length-dependent manner, suggesting disruption of cell metabolism. In sum, our study revealed that PFASs with shorter carbon chains are less toxic than PFOA, and that exposure to sublethal dosage of PFOA, PFHxA or PFBA affects cell metabolism. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

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

International Nuclear Information System (INIS)

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

2015-01-01

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. (paper)

Biological evaluation of dental materials, in vitro and in vivo

International Nuclear Information System (INIS)

Kawahara, H.

1982-01-01

In this paper, the correlation between the user of tissue culture for in vitro tests and the tissue irritability and pupal response observed in in vitro tests, will be discussed. It would produce confusion if dental materials were standardised with the unreliable parameter of the living system in dynamic balance. Biological tests, both in vitro and in vivo, should be used for pre-standards testing, without any political control to establish physicochemical standards. As a first step, corrosion tests and the dissolution dosje of toxic components from the material in the tissue culture medium and/or artificial salvia should be standardised under conditions simulating the oral environment. The CNC method and photo-pattern analysis are used for the interpretation of cytotoxicity. The need for biological testing, both in vitro and in vivo, definitely exists in order to obtain physicochemical standards, with a biological simulation depending upon the feedback obtained from the results of in vitro and in vivo tests

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.

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

Aquatic toxicity testing of silver nanoparticles – a matter of timing

DEFF Research Database (Denmark)

Sørensen, Sara Nørgaard; Owsianiak, Mikolaj; Engelbrekt, Christian

, and difficulties in controlling and/or describing the characteristics of the tested NPs. These issues may be related to the widespread approach of using freshly prepared stock solutions for ecotoxicity testing, as the introduction of NPs into aqueous media initiates time-dependent processes that possibly interfere...... of the test. Ultimately, the aim is better control of the AgNPs in the algal test system and improved prerequisites for describing their toxicity to alga. The underlying hypothesis is that a large part in the variability of AgNPs toxicity to algae can be explained by the kinetics of dissolution and speciation...... of Ag ions in the test media. To reduce the amount of time in which changes to NPs may occur during testing, the exposure period was minimized. A recently proposed short-term (2h) algal test was applied, using 14C incorporation during photosynthesis as toxic endpoint [1]. For citrate coated spherical Ag...

Ebselen reduces the toxicity of mechlorethamine in A-431 cells via inhibition of apoptosis.

Science.gov (United States)

Lulla, Anju; Pino, Maria A; Piętka-Ottlik, Magdalena; Młochowski, Jacek; Sparavalo, Oleksiy; Billack, Blase

2013-06-01

A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen mustard mechlorethamine (HN2) in vitro. The test compounds included resveratrol, pterostilbene, vitamin C, ebselen, ebselen diselenide, and ebselen-sulfur. Among them, ebselen demonstrated the highest degree of protection against HN2 toxicity. To this end, pretreatment of the cells with ebselen offered protection against the toxicant whereas no protection was observed when cells were first incubated with HN2 and then treated with ebselen. Significant increases in caspase 3 and caspase 9 activities were observed in response to HN2, and ebselen was found to reduce these effects. Taken together, the data presented here indicate that ebselen is an effective countermeasure to nitrogen mustard in vitro, which is worthy of future investigation in vivo. © 2013 Wiley Periodicals, Inc.

In vitro toxicity assessment of extracts derived from sol-gel coatings on polycarbonate intended to be used in food contact applications.

Science.gov (United States)

Séverin, Isabelle; Lionti, Krystelle; Dahbi, Laurence; Loriot, Catherine; Toury, Bérangère; Chagnon, Marie-Christine

2016-07-01

Polycarbonate is a widely used polymer in food contact applications all around the world. However, due to the potential release of Bisphenol A (BPA) during repeated washing cycles, its use becomes compromised as BPA is known for being an endocrine disruptor for rodents. In order to tackle this issue, sol-gel coatings based on organoalkoxysiloxane were developed on PC, to act as a physical barrier. To this end, two sol-gel systems based on tetraethylorthosilicate (TEOS), methyltriethoxysilane (MTES) and 3-glycidyloxypropyltriethoxysilane (GPTES), three common sol-gel precursors, were prepared. The coatings derived from the latter two systems were then studied with regards to their potential toxicity in vitro. Migration tests were performed in food simulants, and the maximal migration was obtained in ethanol 10% (v/v) for one system and in isooctane for the other one. In vitro genotoxicity was assessed with the Ames test (OECD 471) and the micronucleus assay (OECD 487), and no genotoxic effect was observed. Moreover, the estrogenic activity of the extracts was studied with a transcriptional activation assay using transient transfection in human cells; none of the extracts was found estrogenic. These negative in vitro results are highly promising for the future use of these new barrier coating formulations onto food contact materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of an in vitro test system for assessment of male, reproductive toxicity.

Science.gov (United States)

Habas, Khaled; Anderson, Diana; Brinkworth, Martin

2014-02-10

There is a need for improved reproductive toxicology assays that do not require large numbers of animals but are sensitive and informative. Therefore, Staput velocity-sedimentation separation followed by culture of specific mouse testicular cells was used as such a system. The specificity of separation was assessed using immunocytochemistry to identify spermatids, spermatocytes and spermatogonia. The efficacy of the system to detect toxicity was then evaluated by analysing the effects of hydrogen peroxide (H2O2) by the terminal uridine-deoxynucleotide end-labelling (TUNEL) assay to show the rate of apoptosis induced among the different types of germ cells. We found that 2 h of treatment at both 1 and 10 μM induced increases of over ∼10-fold in the percentage of apoptotic cells (p≤0.001), confirming that testicular germ cells are prone to apoptosis at very low concentrations of H2O2. It was also demonstrated for the first time for this compound that spermatogonia are significantly more susceptible than spermatocytes, which are more affected than spermatids. This reflects the proportion of actively dividing cells in these cell types, suggesting a mechanism for the differential sensitivity. The approach should thus form the basis of a useful test system for reproductive and genetic toxicology in the future. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

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.

Is the OECD acute worm toxicity test environmentally relevant? The effect of mineral form on calculated lead toxicity

International Nuclear Information System (INIS)

Davies, N.A.Nicola A.; Hodson, M.E.Mark E.; Black, S.Stuart

2003-01-01

The current OECD acute worm toxicity test does not relate well to ambient conditions. - In a series of experiments the toxicity of lead to worms in soil was determined following the draft OECD earthworm reproduction toxicity protocol except that lead was added as solid lead nitrate, carbonate and sulphide rather than as lead nitrate solution as would normally be the case. The compounds were added to the test soil to give lead concentrations of 625-12500 μg Pb g -1 of soil. Calculated toxicities of the lead decreased in the order nitrate>carbonate>sulphide, the same order as the decrease in the solubility of the metal compounds used. The 7-day LC 50 (lethal concentration when 50% of the population is killed) for the nitrate was 5321±275 μg Pb g -1 of soil and this did not change with time. The LC 50 values for carbonate and sulphide could not be determined at the concentration ranges used. The only parameter sensitive enough to distinguish the toxicities of the three compounds was cocoon (egg) production. The EC 50 s for cocoon production (the concentration to produce a 50% reduction in cocoon production) were 993, 8604 and 10246 μg Pb g -1 of soil for lead nitrate, carbonate and sulphide, respectively. Standard toxicity tests need to take into account the form in which the contaminant is present in the soil to be of environmental relevance

Potent In Vitro Antifungal Activities of Naturally Occurring Acetylenic Acids▿

Science.gov (United States)

Li, Xing-Cong; Jacob, Melissa R.; Khan, Shabana I.; Ashfaq, M. Khalid; Babu, K. Suresh; Agarwal, Ameeta K.; ElSohly, Hala N.; Manly, Susan P.; Clark, Alice M.

2008-01-01

Our continuing effort in antifungal natural product discovery has led to the identification of five 6-acetylenic acids with chain lengths from C16 to C20: 6-hexadecynoic acid (compound 1), 6-heptadecynoic acid (compound 2), 6-octadecynoic acid (compound 3), 6-nonadecynoic acid (compound 4), and 6-icosynoic acid (compound 5) from the plant Sommera sabiceoides. Compounds 2 and 5 represent newly isolated fatty acids. The five acetylenic acids were evaluated for their in vitro antifungal activities against Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Trichophyton mentagrophytes, and Trichophyton rubrum by comparison with the positive control drugs amphotericin B, fluconazole, ketoconazole, caspofungin, terbinafine, and undecylenic acid. The compounds showed various degrees of antifungal activity against the 21 tested strains. Compound 4 was the most active, in particular against the dermatophytes T. mentagrophytes and T. rubrum and the opportunistic pathogens C. albicans and A. fumigatus, with MICs comparable to several control drugs. Inclusion of two commercially available acetylenic acids, 9-octadecynoic acid (compound 6) and 5,8,11,14-eicosatetraynoic acid (compound 7), in the in vitro antifungal testing further demonstrated that the antifungal activities of the acetylenic acids were associated with their chain lengths and positional triple bonds. In vitro toxicity testing against mammalian cell lines indicated that compounds 1 to 5 were not toxic at concentrations up to 32 μM. Furthermore, compounds 3 and 4 did not produce obvious toxic effects in mice at a dose of 34 μmol/kg of body weight when administered intraperitoneally. Taking into account the low in vitro and in vivo toxicities and significant antifungal potencies, these 6-acetylenic acids may be excellent leads for further preclinical studies. PMID:18458131

Potent in vitro antifungal activities of naturally occurring acetylenic acids.

Science.gov (United States)

Li, Xing-Cong; Jacob, Melissa R; Khan, Shabana I; Ashfaq, M Khalid; Babu, K Suresh; Agarwal, Ameeta K; Elsohly, Hala N; Manly, Susan P; Clark, Alice M

2008-07-01

Our continuing effort in antifungal natural product discovery has led to the identification of five 6-acetylenic acids with chain lengths from C(16) to C(20): 6-hexadecynoic acid (compound 1), 6-heptadecynoic acid (compound 2), 6-octadecynoic acid (compound 3), 6-nonadecynoic acid (compound 4), and 6-icosynoic acid (compound 5) from the plant Sommera sabiceoides. Compounds 2 and 5 represent newly isolated fatty acids. The five acetylenic acids were evaluated for their in vitro antifungal activities against Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Trichophyton mentagrophytes, and Trichophyton rubrum by comparison with the positive control drugs amphotericin B, fluconazole, ketoconazole, caspofungin, terbinafine, and undecylenic acid. The compounds showed various degrees of antifungal activity against the 21 tested strains. Compound 4 was the most active, in particular against the dermatophytes T. mentagrophytes and T. rubrum and the opportunistic pathogens C. albicans and A. fumigatus, with MICs comparable to several control drugs. Inclusion of two commercially available acetylenic acids, 9-octadecynoic acid (compound 6) and 5,8,11,14-eicosatetraynoic acid (compound 7), in the in vitro antifungal testing further demonstrated that the antifungal activities of the acetylenic acids were associated with their chain lengths and positional triple bonds. In vitro toxicity testing against mammalian cell lines indicated that compounds 1 to 5 were not toxic at concentrations up to 32 muM. Furthermore, compounds 3 and 4 did not produce obvious toxic effects in mice at a dose of 34 mumol/kg of body weight when administered intraperitoneally. Taking into account the low in vitro and in vivo toxicities and significant antifungal potencies, these 6-acetylenic acids may be excellent leads for further preclinical studies.

A comparison of sediment toxicity test methods at three Great Lake Areas of Concern

Science.gov (United States)

Burton, G. Allen; Ingersoll, Christopher G.; Burnett, LouAnn C.; Henry, Mary; Hinman, Mark L.; Klaine, Stephen J.; Landrum, Peter F.; Ross, Phillipe; Tuchman, Marc

1996-01-01

The significance of sediment contamination is often evaluated using sediment toxicity (bioassay) testing. There are relatively few “standardized” test methods for evaluating sediments. Popular sediment toxicity methods examine the extractable water (elutriate), interstitial water, or whole (bulk) sediment phases using test species spanning the aquatic food chain from bacteria to fish. The current study was designed to evaluate which toxicity tests were most useful in evaluations of sediment contamination at three Great Lake Areas of Concern. Responses of 24 different organisms including fish, mayflies, amphipods, midges, cladocerans, rotifers, macrophytes, algae, and bacteria were compared using whole sediment or elutriate toxicity assays. Sediments from several sites in the Buffalo River, Calumet River (Indiana Harbor), and Saginaw River were tested, as part of the U.S. Environmental Protection Agency's (USEPA) Assessment and Remediation of Contaminated Sediments (ARCS) Project. Results indicated several assays to be sensitive to sediment toxicity and able to discriminate between differing levels of toxicity. Many of the assay responses were significantly correlated to other toxicity responses and were similar based on factor analysis. For most applications, a test design consisting of two to three assays should adequately detect sediment toxicity, consisting of various groupings of the following species: Hyalella azteca, Ceriodaphnia dubia, Chironomus riparius, Chironomus tentans, Daphnia magna, Pimephales promelas, Hexagenia bilineata, Diporeia sp., Hydrilla verticillata, or Lemna minor.

40 CFR 797.1930 - Mysid shrimp acute toxicity test.

Science.gov (United States)

2010-07-01

... test organisms and eliminating loss of organisms in outflow water. (6) “Static system” means a test..., procedures, and mysids from the same population or culture container, except that none of the chemical is... in chronic toxicity tests should originate from laboratory cultures in order to ensure the...

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 ...

Evaluation of an adherent mouse embryonic stem cell in vitro assay to predict developmental toxicity of ToxCast chemicals.

Science.gov (United States)

The potential for most environmental chemicals to produce developmental toxicity is unknown. Mouse embryonic stem cell (mESC) assays are an alternative in vitro model to assess chemicals. The chemical space evaluated using mESC and compared to in vivo is limited. We used an adher...

Potential countersample materials for in vitro simulation wear testing.

Science.gov (United States)

Shortall, Adrian C; Hu, Xiao Q; Marquis, Peter M

2002-05-01

Any laboratory investigation of the wear resistance of dental materials needs to consider oral conditions so that in vitro wear results can be correlated with in vivo findings. The choice of the countersample is a critical factor in establishing the pattern of tribological wear and in achieving an efficient in vitro wear testing system. This research investigated the wear behavior and surface characteristics associated with three candidate countersample materials used for in vitro wear testing in order to identify a possible suitable substitute for human dental enamel. Three candidate materials, stainless steel, steatite and dental porcelain were evaluated and compared to human enamel. A variety of factors including hardness, wear surface evolution and frictional coefficients were considered, relative to the tribology of the in vivo situation. The results suggested that the dental porcelain investigated bore the closest similarity to human enamel of the materials investigated. Assessment of potential countersample materials should be based on the essential tribological simulation supported by investigations of mechanical, chemical and structural properties. The selected dental porcelain had the best simulating ability among the three selected countersample materials and this class of material may be considered as a possible countersample material for in vitro wear test purposes. Further studies are required, employing a wider range of dental ceramics, in order to optimise the choice of countersample material for standardized in vitro wear testing.

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.

Analysis of Chemical Bioactivity through In Vitro Profiling ...

Science.gov (United States)

Safety assessment of drugs and environmental chemicals relies extensively on animal testing. However, the quantity of chemicals needing assessment and challenges of species extrapolation drive the development of alternative approaches. The EPA’s ToxCast and the multiagency Tox21 programs address this through use of an extensive in vitro screening program to generate data on a large library of important environmental chemicals. These in vitro assays encompass both cell-free, biochemical assays targeting proteins that may be potential molecular initiating events and cellular assays that provide coverage of critical signaling pathways and toxicity phenotypes. Effects on model organisms such as the developing zebrafish, are also part of the testing strategy. A variety of computational approaches are used to analyze the resulting complex data sets to gain insight in to inherent biological activity of chemicals and possible mechanisms of toxicity. Several case studies including identification of modulators of estrogen receptor and aromatic hydrocarbon receptor pathways with effects in primary human cell systems will be described. In addition, existing in vivo data from a subset of the chemicals was used to anchor predictive models using in vitro data for a number of adverse endpoints including reproductive and developmental toxicities. The strengths and weaknesses of this approach will be described. This work does not necessarily reflect official Agency policy. Pres

Incorporating new technologies into toxicity testing and risk assessment: moving from 21st century vision to a data-driven framework.

Science.gov (United States)

Thomas, Russell S; Philbert, Martin A; Auerbach, Scott S; Wetmore, Barbara A; Devito, Michael J; Cote, Ila; Rowlands, J Craig; Whelan, Maurice P; Hays, Sean M; Andersen, Melvin E; Meek, M E Bette; Reiter, Lawrence W; Lambert, Jason C; Clewell, Harvey J; Stephens, Martin L; Zhao, Q Jay; Wesselkamper, Scott C; Flowers, Lynn; Carney, Edward W; Pastoor, Timothy P; Petersen, Dan D; Yauk, Carole L; Nong, Andy

2013-11-01

Based on existing data and previous work, a series of studies is proposed as a basis toward a pragmatic early step in transforming toxicity testing. These studies were assembled into a data-driven framework that invokes successive tiers of testing with margin of exposure (MOE) as the primary metric. The first tier of the framework integrates data from high-throughput in vitro assays, in vitro-to-in vivo extrapolation (IVIVE) pharmacokinetic modeling, and exposure modeling. The in vitro assays are used to separate chemicals based on their relative selectivity in interacting with biological targets and identify the concentration at which these interactions occur. The IVIVE modeling converts in vitro concentrations into external dose for calculation of the point of departure (POD) and comparisons to human exposure estimates to yield a MOE. The second tier involves short-term in vivo studies, expanded pharmacokinetic evaluations, and refined human exposure estimates. The results from the second tier studies provide more accurate estimates of the POD and the MOE. The third tier contains the traditional animal studies currently used to assess chemical safety. In each tier, the POD for selective chemicals is based primarily on endpoints associated with a proposed mode of action, whereas the POD for nonselective chemicals is based on potential biological perturbation. Based on the MOE, a significant percentage of chemicals evaluated in the first 2 tiers could be eliminated from further testing. The framework provides a risk-based and animal-sparing approach to evaluate chemical safety, drawing broadly from previous experience but incorporating technological advances to increase efficiency.

Incorporating New Technologies Into Toxicity Testing and Risk Assessment: Moving From 21st Century Vision to a Data-Driven Framework

Science.gov (United States)

Thomas, Russell S.

2013-01-01

Based on existing data and previous work, a series of studies is proposed as a basis toward a pragmatic early step in transforming toxicity testing. These studies were assembled into a data-driven framework that invokes successive tiers of testing with margin of exposure (MOE) as the primary metric. The first tier of the framework integrates data from high-throughput in vitro assays, in vitro-to-in vivo extrapolation (IVIVE) pharmacokinetic modeling, and exposure modeling. The in vitro assays are used to separate chemicals based on their relative selectivity in interacting with biological targets and identify the concentration at which these interactions occur. The IVIVE modeling converts in vitro concentrations into external dose for calculation of the point of departure (POD) and comparisons to human exposure estimates to yield a MOE. The second tier involves short-term in vivo studies, expanded pharmacokinetic evaluations, and refined human exposure estimates. The results from the second tier studies provide more accurate estimates of the POD and the MOE. The third tier contains the traditional animal studies currently used to assess chemical safety. In each tier, the POD for selective chemicals is based primarily on endpoints associated with a proposed mode of action, whereas the POD for nonselective chemicals is based on potential biological perturbation. Based on the MOE, a significant percentage of chemicals evaluated in the first 2 tiers could be eliminated from further testing. The framework provides a risk-based and animal-sparing approach to evaluate chemical safety, drawing broadly from previous experience but incorporating technological advances to increase efficiency. PMID:23958734

Toxicity tests, antioxidant activity, and antimicrobial activity of chitosan

Science.gov (United States)

Kurniasih, M.; Purwati; Dewi, R. S.

2018-04-01

Chitosan is a naturally occurring cationic biopolymer, obtained by alkaline deacetylation of chitin. This research aims to investigate the toxicity, antioxidant activity and antibacterial activity of chitosan from shrimp chitin. In this study, chitin extracted from shrimp waste material. Chitin is then deacetylation with 60% NaOH so that chitosan produced. Degrees of deacetylation, molecular weight, toxicity test, antioxidant activity and antimicrobial activity of chitosan then evaluated. Toxicity test using Brine Shrimp Lethality Test. The antioxidant analysis was performed using DPPH method (2, 2-diphenyl-1-picrylhydrazyl) and FTC method (ferric thiocyanate) in which the radical formed will reduce Ferro to Ferri resulting in a complex with thiocyanate. To determine the antibacterial activity of Staphylococcus aureus, antifungal in Candida albicans and Aspergillus niger by measuring antimicrobial effects and minimum inhibitory concentrations (MIC). Based on the result of research, the value of degrees of deacetylation, molecular weight, and LC50 values of chitosan synthesis was 94,32, 1052.93 g/mol and 1364.41 ppm, respectively. In general, the antioxidative activities increased as the concentration of chitosan increased. MIC value of chitosan against S. aureus, C. albicans, and A. niger was 10 ppm, 15.6 ppm, and 5 ppm, respectively.

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.

Prediction of toxicity and comparison of alternatives using WebTEST (Web-services Toxicity Estimation Software Tool)(Bled Slovenia)

Science.gov (United States)

A Java-based web service is being developed within the US EPA’s Chemistry Dashboard to provide real time estimates of toxicity values and physical properties. WebTEST can generate toxicity predictions directly from a simple URL which includes the endpoint, QSAR method, and ...

Study on irradiation of freshening ginseng and toxicity test

International Nuclear Information System (INIS)

Wang Ziwen; Xu Dechun; Yang Wanqi

1991-01-01

The ginsengs irradiated by 1 or 2 kGy of γ-rays have been stored for 6 months under room temperature. Its freshening rates was 86.67% and 88.33% respectively. The saponin content was maintained. The irradiated ginsengs had the vigour of sap fully and beautiful colour. Therefore they can be stored much longer for sell. The toxicity test showed that there was no toxicity for irradiated ginsengs

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

International Nuclear Information System (INIS)

Specht, W.L.; Harmon, S.M.

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

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.

Science.gov (United States)

2010-07-01

... on the chronic toxicity of chemical substances and mixtures (“chemicals”) subject to environmental... with the test design into retention chambers within the test and the control chambers. Mysids in the... and experimental history. Mysids used for establishing laboratory cultures may be purchased...

In vitro profiling of toxic effects of prominent environmental lower-chlorinated PCB congeners linked with endocrine disruption and tumor promotion.

Science.gov (United States)

Pěnčíková, Kateřina; Svržková, Lucie; Strapáčová, Simona; Neča, Jiří; Bartoňková, Iveta; Dvořák, Zdeněk; Hýžďalová, Martina; Pivnička, Jakub; Pálková, Lenka; Lehmler, Hans-Joachim; Li, Xueshu; Vondráček, Jan; Machala, Miroslav

2018-06-01

The mechanisms contributing to toxic effects of airborne lower-chlorinated PCB congeners (LC-PCBs) remain poorly characterized. We evaluated in vitro toxicities of environmental LC-PCBs found in both indoor and outdoor air (PCB 4, 8, 11, 18, 28 and 31), and selected hydroxylated metabolites of PCB 8, 11 and 18, using reporter gene assays, as well as other functional cellular bioassays. We focused on processes linked with endocrine disruption, tumor promotion and/or regulation of transcription factors controlling metabolism of both endogenous compounds and xenobiotics. The tested LC-PCBs were found to be mostly efficient anti-androgenic (within nanomolar - micromolar range) and estrogenic (at micromolar concentrations) compounds, as well as inhibitors of gap junctional intercellular communication (GJIC) at micromolar concentrations. PCB 8, 28 and 31 were found to partially inhibit the aryl hydrocarbon receptor (AhR)-mediated activity. The tested LC-PCBs were also partial constitutive androstane receptor (CAR) and pregnane X receptor (PXR) agonists, with PCB 4, 8 and 18 being the most active compounds. They were inactive towards other nuclear receptors, such as vitamin D receptor, thyroid receptor α, glucocorticoid receptor or peroxisome proliferator-activated receptor γ. We found that only PCB 8 contributed to generation of oxidative stress, while all tested LC-PCBs induced arachidonic acid release (albeit without further modulations of arachidonic acid metabolism) in human lung epithelial cells. Importantly, estrogenic effects of hydroxylated (OH-PCB) metabolites of LC-PCBs (4-OH-PCB 8, 4-OH-PCB 11 and 4'-OH-PCB 18) were higher than those of the parent PCBs, while their other toxic effects were only slightly altered or suppressed. This suggested that metabolism may alter toxicity profiles of LC-PCBs in a receptor-specific manner. In summary, anti-androgenic and estrogenic activities, acute inhibition of GJIC and suppression of the AhR-mediated activity were

In-vitro Cell Exposure Studies for the Assessment of Nanoparticle Toxicity in the Lung - A Dialogue between Aerosol Science and Biology

Energy Technology Data Exchange (ETDEWEB)

Hanns-Rudolf, Paur; Cassee, Flemming R.; Teeguarden, Justin G.; Fissan, Heinz; Diabate, Silvia; Aufderheide, M.; Kreyling, Wolfgang G.; Hanninen, Otto; Kasper, G.; Riediker, Michael; Rothen-Rutishauser, Barbara; Schmid, Otmar

2011-10-01

The rapid introduction of engineered nanostructured materials into numerous industrial and consumer products will result in enhanced exposure to engineered nanoparticles. Workplace exposure has been identified as the most likely source of uncontrolled inhalation of engineered aerosolized nanoparticles, but release of engineered nanoparticles may occur at any stage of the lifecycle of consumer products. The dynamic development of new nanomaterials with possibly unknown toxicological effects poses a challenge for the assessment of nanoparticle induced toxicity and safety. In this consensus document from a workshop on in-vitro cell systems for nanotoxicity testing an overview is given of the main issues concerning inhalation exposure to nanoparticles, lung physiology, nanoparticle-related biological mechanisms, in-vitro cell exposure systems for nanoparticles and social aspects of nanotechnology. The workshop participants recognized the large potential of in-vitro cell exposure systems for reliable, high-throughput screening of nanotoxicity. For the investigation of pulmonary nanotoxicity, a strong preference was expressed for air-liquid interface (ALI) cell exposure systems (rather than submerged cell exposure systems) as they closely resemble in-vivo conditions in the lungs and they allow for unaltered and dosimetrically accurate delivery of aerosolized nanoparticles to the cells. The members of the workshop believe that further advances in in-vitro cell exposure studies would be greatly facilitated by a more active role of the aerosol scientists. The technical know-how for developing and running ALI in-vitro exposure systems is available in the aerosol community and at the same time biologists/toxicologists are required for proper assessment of the biological impact of nanoparticles.

In-vitro Cell Exposure Studies for the Assessment of Nanoparticle Toxicity in the Lung - A Dialogue between Aerosol Science and Biology

International Nuclear Information System (INIS)

Hanns-Rudolf, Paur; Cassee, Flemming R.; Teeguarden, Justin G.; Fissan, Heinz; Diabate, Silvia; Aufderheide, M.; Kreyling, Wolfgang G.; Hanninen, Otto; Kasper, G.; Riediker, Michael; Rothen-Rutishauser, Barbara; Schmid, Otmar

2011-01-01

The rapid introduction of engineered nanostructured materials into numerous industrial and consumer products will result in enhanced exposure to engineered nanoparticles. Workplace exposure has been identified as the most likely source of uncontrolled inhalation of engineered aerosolized nanoparticles, but release of engineered nanoparticles may occur at any stage of the lifecycle of consumer products. The dynamic development of new nanomaterials with possibly unknown toxicological effects poses a challenge for the assessment of nanoparticle induced toxicity and safety. In this consensus document from a workshop on in-vitro cell systems for nanotoxicity testing an overview is given of the main issues concerning inhalation exposure to nanoparticles, lung physiology, nanoparticle-related biological mechanisms, in-vitro cell exposure systems for nanoparticles and social aspects of nanotechnology. The workshop participants recognized the large potential of in-vitro cell exposure systems for reliable, high-throughput screening of nanotoxicity. For the investigation of pulmonary nanotoxicity, a strong preference was expressed for air-liquid interface (ALI) cell exposure systems (rather than submerged cell exposure systems) as they closely resemble in-vivo conditions in the lungs and they allow for unaltered and dosimetrically accurate delivery of aerosolized nanoparticles to the cells. The members of the workshop believe that further advances in in-vitro cell exposure studies would be greatly facilitated by a more active role of the aerosol scientists. The technical know-how for developing and running ALI in-vitro exposure systems is available in the aerosol community and at the same time biologists/toxicologists are required for proper assessment of the biological impact of nanoparticles.

Alternative methods for toxicity assessments in fish: comparison of the fish embryo toxicity and the larval growth and survival tests in zebrafish and fathead minnows.

Science.gov (United States)

Jeffries, Marlo K Sellin; Stultz, Amy E; Smith, Austin W; Rawlings, Jane M; Belanger, Scott E; Oris, James T

2014-11-01

An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative, and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. In the present study, the performances of the FET test and the larval growth and survival (LGS; a standard toxicity testing method) test in zebrafish and fathead minnows were evaluated. This required that testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and that the performance of these testing strategies be evaluated by comparing the median lethal concentrations of 2 reference toxicants, 3,4-dicholoraniline and ammonia, obtained via each of the test types. The results showed that procedures for the zebrafish FET test can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for 3,4-dicholoraniline but not ammonia; therefore, conclusions regarding which test types offer the least or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and that further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy. © 2014 SETAC.

Evaluation of natural toxicity on MICROTOX solid-phase test. The pelitic normalization

International Nuclear Information System (INIS)

Onorati, F.; Pellegrini, D.; Ausili, A.

1999-01-01

In sediment toxicity testing Microtox solid-phase test (SPT) is one of the most used and standardised bioassay. Nevertheless, its real sensitivity and discriminatory power is still unclear, because of several interferences principally related to the matrix composition. Using reference sediments, characterised with chemical and physical analysis, it was possible to find a significant relationship between their natural toxicity and the pelitic fraction that allows to estimate the natural component of the acute toxicity in contaminated samples. This relationship arrows a more sensitive and valid interpretation than raw data and it is used to develop a sediment toxicity index (STI) based on radio to reference (RTR) concept, applicable to harbour contaminated samples [it

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.

Critical analysis of 3-D organoid in vitro cell culture models for high-throughput drug candidate toxicity assessments.

Science.gov (United States)

Astashkina, Anna; Grainger, David W

2014-04-01

Drug failure due to toxicity indicators remains among the primary reasons for staggering drug attrition rates during clinical studies and post-marketing surveillance. Broader validation and use of next-generation 3-D improved cell culture models are expected to improve predictive power and effectiveness of drug toxicological predictions. However, after decades of promising research significant gaps remain in our collective ability to extract quality human toxicity information from in vitro data using 3-D cell and tissue models. Issues, challenges and future directions for the field to improve drug assay predictive power and reliability of 3-D models are reviewed. Copyright © 2014 Elsevier B.V. All rights reserved.

Subjective and objective screening tests for hydroxychloroquine toxicity.

Science.gov (United States)

Cukras, Catherine; Huynh, Nancy; Vitale, Susan; Wong, Wai T; Ferris, Fredrick L; Sieving, Paul A

2015-02-01

To compare subjective and objective clinical tests used in the screening for hydroxychloroquine retinal toxicity to multifocal electroretinography (mfERG) reference testing. Prospective, single-center, case control study. Fifty-seven patients with a previous or current history of hydroxychloroquine treatment of more than 5 years' duration. Participants were evaluated with a detailed medical history, dilated ophthalmologic examination, color fundus photography, fundus autofluorescence (FAF) imaging, spectral-domain (SD) optical coherence tomography (OCT), automated visual field testing (10-2 visual field mean deviation [VFMD]), and mfERG testing. We used mfERG test parameters as a gold standard to divide participants into 2 groups: those affected by hydroxychloroquine-induced retinal toxicity and those unaffected. We assessed the association of various imaging and psychophysical variables in the affected versus the unaffected group. Fifty-seven study participants (91.2% female; mean age, 55.7±10.4 years; mean duration of hydroxychloroquine treatment, 15.0±7.5 years) were divided into affected (n = 19) and unaffected (n = 38) groups based on mfERG criteria. Mean age and duration of hydroxychloroquine treatment did not differ statistically between groups. Mean OCT retinal thickness measurements in all 9 macular subfields were significantly lower (<40 μm) in the affected group (P < 0.01 for all comparisons) compared with those in the unaffected group. Mean VFMD was 11 dB lower in the affected group (P < 0.0001). Clinical features indicative of retinal toxicity were scored for the 2 groups and were detected in 68.4% versus 0.0% using color fundus photographs, 73.3% versus 9.1% using FAF images, and 84.2% versus 0.0% on the scoring for the perifoveal loss of the photoreceptor ellipsoid zone on SD-OCT for affected and unaffected participants, respectively. Using a polynomial modeling approach, OCT inner ring retinal thickness measurements and Humphrey 10-2 VFMD were

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

Antimalarial activity of plumbagin in vitro and in animal models.

Science.gov (United States)

Sumsakul, Wiriyaporn; Plengsuriyakarn, Tullayakorn; Chaijaroenkul, Wanna; Viyanant, Vithoon; Karbwang, Juntra; Na-Bangchang, Kesara

2014-01-12

Plumbagin is the major active constituent in several plants including Plumbago indica Linn. (root). This compound has been shown to exhibit a wide spectrum of biological and pharmacological activities. The present study aimed to evaluate the in vitro and in vivo antimalarial activity of plumbagin including its acute and subacute toxicity in mice. In vitro antimalarial activity of plumbagin against K1 and 3D7 Plasmodium falciparum clones were assessed using SYBR Green I based assay. In vivo antimalarial activity was investigated in Plasmodium berghei-infected mouse model (a 4-day suppressive test). Plumbagin exhibited promising antimalarial activity with in vitro IC50 (concentration that inhibits parasite growth to 50%) against 3D7 chloroquine-sensitive P. falciparum and K1 chloroquine-resistant P. falciparum clones of 580 (270-640) and 370 (270-490) nM, respectively. Toxicity testing indicated relatively low toxicity at the dose levels up to 100 (single oral dose) and 25 (daily doses for 14 days) mg/kg body weight for acute and subacute toxicity, respectively. Chloroquine exhibited the most potent antimalarial activity in mice infected with P. berghei ANKA strain with respect to its activity on the reduction of parasitaemia on day 4 and the prolongation of survival time. Plumbagin at the dose of 25 mg/kg body weight given for 4 days was safe and produced weak antimalarial activity. Chemical derivatization of the parent compound or preparation of modified formulation is required to improve its systemic bioavailability.

Indicators of Ceriodaphnia dubia chronic toxicity test performance and sensitivity

Energy Technology Data Exchange (ETDEWEB)

Rosebrock, M.M.; Bedwell, N.J.; Ausley, L.W. [North Carolina Division of Environmental Management, Raleigh, NC (United States)

1994-12-31

The North Carolina Division of Environmental Management has begun evaluation of the sensitivity of test results used for measuring chronic whole effluent toxicity in North Carolina wastewater discharges. Approximately 67% of 565 facilities required to monitor toxicity by an NPDES permit perform a Ceriodaphnia dubia chronic, single effluent concentration (pass/fail) analysis. Data from valid Ceriodaphnia dubia chronic pass/fail tests performed by approximately 20 certified biological laboratories and submitted by North Carolina NPDES permittees were recorded beginning January 1992. Control and treatment reproduction data from over 2,500 tests submitted since 1992 were analyzed to determine the minimum significant difference (MSD) at a 99% confidence level for each test and the percent reduction from the control mean that the MSD represents (%MSD) for each certified laboratory. Initial results for the 20 laboratories indicate that the average intralaboratory percent MSD ranges 12.72% (n = 367) to 34.91% (n = 7) with an average of 23.08%. Additionally, over 3,800 tests were analyzed to determine the coefficient of variation (CV) for control reproduction for each test and the average for each certified biological laboratory. Preliminary review indicates that average interlaboratory control reproduction CV values range from 10.59% (n = 367) to 31.08% (n = 572) with a mean of 20.35%. The statistics investigated are indicators of intra/interlaboratory performance and sensitivity of Ceriodaphnia chronic toxicity analyses.

In vitro anticancer activity, toxicity and structure-activity relationships of phyllostictine A, a natural oxazatricycloalkenone produced by the fungus Phyllosticta cirsii

International Nuclear Information System (INIS)

Le Calve, Benjamin; Lallemand, Benjamin; Perrone, Carmen; Lenglet, Gaelle; Depauw, Sabine; Van Goietsenoven, Gwendoline; Bury, Marina; Vurro, Maurizio; Herphelin, Francoise; Andolfi, Anna; Zonno, Maria Chiara; Mathieu, Veronique; Dufrasne, Francois; Van Antwerpen, Pierre; Poumay, Yves

2011-01-01

The in vitro anticancer activity and toxicity of phyllostictine A, a novel oxazatricycloalkenone recently isolated from a plant-pathogenic fungus (Phyllosticta cirsii) was characterized in six normal and five cancer cell lines. Phyllostictine A displays in vitro growth-inhibitory activity both in normal and cancer cells without actual bioselectivity, while proliferating cells appear significantly more sensitive to phyllostictine A than non-proliferating ones. The main mechanism of action by which phyllostictine displays cytotoxic effects in cancer cells does not seem to relate to a direct activation of apoptosis. In the same manner, phyllostictine A seems not to bind or bond with DNA as part of its mechanism of action. In contrast, phyllostictine A strongly reacts with GSH, which is a bionucleophile. The experimental data from the present study are in favor of a bonding process between GSH and phyllostictine A to form a complex though Michael attack at C=C bond at the acrylamide-like system. Considering the data obtained, two new hemisynthesized phyllostictine A derivatives together with three other natural phyllostictines (B, C and D) were also tested in vitro in five cancer cell lines. Compared to phyllostictine A, the two derivatives displayed a higher, phyllostictines B and D a lower, and phyllostictine C an almost equal, growth-inhibitory activity, respectively. These results led us to propose preliminary conclusions in terms of the structure-activity relationship (SAR) analyses for the anticancer activity of phyllostictine A and its related compounds, at least in vitro.

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.

Anthelmintic effect of thymol and thymol acetate on sheep gastrointestinal nematodes and their toxicity in mice

Directory of Open Access Journals (Sweden)

Weibson Paz Pinheiro André

Full Text Available Abstract Thymol is a monoterpene and acetylation form of this compound can reduce the toxicity and enhance its biological effects. The objective of this study was to evaluate the effect of thymol and thymol acetate (TA on egg, larva and adult Haemonchus contortus and the cuticular changes, acute toxicity in mice and the efficacy on sheep gastrointestinal nematodes. In vitro tests results were analyzed by analysis of variance (ANOVA and followed by comparison with Tukey test or Bonferroni. The efficacy of in vivo test was calculated by the BootStreet program. In the egg hatch test (EHT, thymol (0.5 mg/mL and TA (4 mg/mL inhibited larval hatching by 98% and 67.1%, respectively. Thymol and TA (8 mg/mL inhibited 100% of larval development. Thymol and TA (800 µg/mL reduced the motility of adult worms, by 100% and 83.4%, respectively. Thymol caused cuticular changes in adult worm teguments. In the acute toxicity test, the LD50 of thymol and TA were 1,350.9 mg/kg and 4,144.4 mg/kg, respectively. Thymol and TA reduced sheep egg count per gram of faeces (epg by 59.8% and 76.2%, respectively. In in vitro tests thymol presented better anthelmintic activity than TA. However TA was less toxic and in in vivo test efficacy was similar.

Toxicity and mutagenicity of low-metallic automotive brake pad materials.

Science.gov (United States)

Malachova, Katerina; Kukutschova, Jana; Rybkova, Zuzana; Sezimova, Hana; Placha, Daniela; Cabanova, Kristina; Filip, Peter

2016-09-01

Organic friction materials are standardly used in brakes of small planes, railroad vehicles, trucks and passenger cars. The growing transportation sector requires a better understanding of the negative impact related to the release of potentially hazardous materials into the environment. This includes brakes which can release enormous quantities of wear particulates. This paper addresses in vitro detection of toxic and mutagenic potency of one model and two commercially available low-metallic automotive brake pads used in passenger cars sold in the EU market. The model pad made in the laboratory was also subjected to a standardized brake dynamometer test and the generated non-airborne wear particles were also investigated. Qualitative "organic composition" was determined by GC/MS screening of dichloromethane extracts. Acute toxicity and mutagenicity of four investigated sample types were assessed in vitro by bioluminescence assay using marine bacteria Vibrio fischeri and by two bacterial bioassays i) Ames test on Salmonella typhimurium His(-) and ii) SOS Chromotest using Escherichia coli PQ37 strain. Screening of organic composition revealed a high variety of organic compounds present in the initial brake pads and also in the generated non-airborne wear debris. Several detected compounds are classified by IARC as possibly carcinogenic to humans, e. g. benzene derivatives. Acute toxicity bioassay revealed a response of bacterial cells after exposure to all samples used. Phenolic resin and wear debris were found to be acutely toxic; however in term of mutagenicity the response was negative. All non-friction exposed brake pad samples (a model pad and two commercial pad samples) were mutagenic with metabolic activation in vitro. Copyright © 2016 Elsevier Inc. All rights reserved.

Application of toxicity testing in the evaluation of reclamation options for oil sands fine tails

International Nuclear Information System (INIS)

Nelson, L.R.; MacKinnon, M.; Gulley, J.R.

1993-01-01

The hot water process for the extraction of bitumen from oil sands leads to the production of large volumes of wastewater and the formation of a large inventory of fine clay tailings. This fine tailings material and its associated water are acutely toxic to various aquatic test organisms during bioassays. An overview is presented of toxicity testing at Syncrude and Suncor, the application of toxicity testing to fine tailings management, and the role in reclamation planning. The main acutely toxic component of the tailings is the polar organic acid fraction, specifically naphthanates. These naphthanates are readily degraded biologically by indigenous microbial populations. Toxicity testing is aimed at assessing the degree of both acute and chronic toxicity and the long term potential for the input of toxins into the environment from various proposed reclamation measures. 28 refs., 6 figs., 2 tabs

Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures

Science.gov (United States)

Oudalova, A. A.; Geras'kin, S. A.; Dikareva, N. S.; Pyatkova, S. V.

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds.

Recent advances in graphene family materials toxicity investigations

International Nuclear Information System (INIS)

Jastrzębska, Agnieszka Maria; Kurtycz, Patrycja; Olszyna, Andrzej Roman

2012-01-01

Recently, graphene family materials (GFMs) have been introduced among all fields of science and still get numerous attention. Also, the applicability of these materials in many areas makes them very attractive. GFMs have attracted both academic and industrial interest as they can produce a dramatic improvement in materials properties at very low filler content. This article presents recent findings on GFMs toxicity properties based on the most current literature. This article studies the effects of GFMs on bacteria, mammalian cells, animals, and plants. This article also reviews in vitro and in vivo test results as well as potential anticancer activity and toxicity mechanisms of GFMs. The effect of functionalization of graphene on pacifying its strong interactions with cells and associated toxic effects was also analyzed. The authors of the article believe that further work should focus on in vitro and in vivo studies on possible interactions between GFMs and different living systems. Further research should also focus on decreasing GFMs toxicity, which still poses a great challenge for in vivo biomedical applications. Consequently, the potential impact of graphene and its derivatives on humans and environmental health is a matter of academic interest. However, potential hazards sufficient for risk assessment first need to be investigated.

Development and application of a sediment toxicity test using the benthic cladoceran Chydorus sphaericus

International Nuclear Information System (INIS)

Dekker, T.; Greve, G.D.; Ter Laak, T.L.; Boivin, M.E.; Veuger, B.; Gortzak, G.; Dumfries, S.; Luecker, S.M.G.; Kraak, M.H.S.; Admiraal, W.; Geest, H.G. van der

2006-01-01

This study reports on the development and application of a whole sediment toxicity test using a benthic cladoceran Chydorus sphaericus, as an alternative for the use of pelagic daphnids. A C. sphaericus laboratory culture was started and its performance under control conditions was optimised. The test was firstly validated by determining dose-response relationships for aqueous cadmium and copper and ammonia, showing a sensitivity of C. sphaericus (96 h LC 5 values of 594 μg Cd/L, 191 μg Cu/L and 46 mg ammonia/L at pH 8) similar to that of daphnids. Next, sediment was introduced into the test system and a series of contaminated sediments from polluted locations were tested. A significant negative correlation between survival and toxicant concentrations was observed. It is concluded that the test developed in the present study using the benthic cladoceran C. sphaericus is suitable for routine laboratory sediment toxicity testing. - A test was developed for assaying sediment toxicity using a commonly occurring small-bodied cladoceran

Toxicity of compounds with endocrine activity in the OECD 421 reproductive toxicity screening test

NARCIS (Netherlands)

Piersma AH; Verhoef A; Elvers LH; Wester PW; LEO; LPI

1998-01-01

The issue of endocrine disruption has, in view of human risk assessment, raised the question on whether more sensitive test methods are needed to detect the reproductive toxic properties of xenobiotic compounds with endocrine properties. We studied six known and alleged endocrine disruptors in an

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.

Inhalation method for delivery of nanoparticles to the Drosophila respiratory system for toxicity testing

International Nuclear Information System (INIS)

Posgai, Ryan; Ahamed, Maqusood; Hussain, Saber M.; Rowe, John J.; Nielsen, Mark G.

2009-01-01

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.

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.

Accelerated in-vitro release testing methods for extended-release parenteral dosage forms.

Science.gov (United States)

Shen, Jie; Burgess, Diane J

2012-07-01

This review highlights current methods and strategies for accelerated in-vitro drug release testing of extended-release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in-situ depot-forming systems and implants. Extended-release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, 'real-time' in-vitro release tests for these dosage forms are often run over a long time period. Accelerated in-vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in-vitro release methods using United States Pharmacopeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended-release parenteral dosage forms, along with the accelerated in-vitro release testing methods currently employed are discussed. Accelerated in-vitro release testing methods with good discriminatory ability are critical for quality control of extended-release parenteral products. Methods that can be used in the development of in-vitro-in-vivo correlation (IVIVC) are desirable; however, for complex parenteral products this may not always be achievable. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

Accelerated in vitro release testing methods for extended release parenteral dosage forms

Science.gov (United States)

Shen, Jie; Burgess, Diane J.

2012-01-01

Objectives This review highlights current methods and strategies for accelerated in vitro drug release testing of extended release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in situ depot-forming systems, and implants. Key findings Extended release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, “real-time” in vitro release tests for these dosage forms are often run over a long time period. Accelerated in vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in vitro release methods using United States Pharmacopoeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended release parenteral dosage forms, along with the accelerated in vitro release testing methods currently employed are discussed. Conclusions Accelerated in vitro release testing methods with good discriminatory ability are critical for quality control of extended release parenteral products. Methods that can be used in the development of in vitro-in vivo correlation (IVIVC) are desirable, however for complex parenteral products this may not always be achievable. PMID:22686344

Mechanisms of cell death induced by infusion sets leachables in in vitro experimental settings.

Science.gov (United States)

Kozlovskaya, Luba; Stepensky, David

2015-01-30

Leachable materials that are released from infusion sets during their use can induce local and systemic toxic effects. We studied the mechanisms and kinetics of cell death induced by infusion sets leachates in vitro using L-929 and bEnd. 3 cells. Changes in cell morphology and metabolic activity were determined using light microscopy and the MTT test, respectively. Detailed analysis of the mechanisms of cell death was performed using membrane integrity and caspases 3 and 7 activity tests, annexin V-FITC/7-AAD analysis by FACS, and DAPI nuclear staining followed by confocal microscopy. Infusion sets released toxic leachables and induced toxic effects. Latex flashball was the most toxic part of the studied infusion sets, and it potently induced cell oncosis via increased permeability of the cell membrane. Latex-induced decrease in cells metabolic activity and cell death were not accompanied by activation of caspases 3 and 7, changes in nuclear morphology, or substantial annexin V-FITC cell staining. Leachables from the tube part of the infusion sets were less toxic, and induced some biochemical changes without altering the cells morphology. Further studies are needed to reveal the in vivo toxicity of infusion sets and its correlation with the results of in vitro toxicity studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Fostering efficacy and toxicity evaluation of traditional Chinese medicine and natural products: Chick embryo as a high throughput model bridging in vitro and in vivo studies.

Science.gov (United States)

Wu, Tong; Yu, Gui-Yuan; Xiao, Jia; Yan, Chang; Kurihara, Hiroshi; Li, Yi-Fang; So, Kwok-Fai; He, Rong-Rong

2018-04-19

Efficacy and safety assessments are essential thresholds for drug candidates from preclinical to clinical research. Conventional mammalian in vivo models cannot offer rapid pharmacological and toxicological screening, whereas cell-based or cell-free in vitro systems often lead to inaccurate results because of the lack of physiological environment. Within the avian species, gallus gallus is the first bird to have its genome sequencing. Meantime, chick embryo is an easily operating, relatively transparent and extensively accessible model, whose physiological and pathological alterations can be visualized by egg candler, staining and image technologies. These features facilitate chick embryo as a high-throughput screening platform bridging in vivo and in vitro gaps in the pharmaceutical research. Due to the complicated ingredients and multiple-targets natures of traditional Chinese medicine (TCM), testing the efficacy and safety of TCM by in vitro methods are laborious and inaccurate, while testing in mammalian models consume massive cost and time. As such, the productive living organism chick embryo serves as an ideal biological system for pharmacodynamics studies of TCM. Herein, we comprehensively update recent progresses on the specialty of chick embryo in evaluation of efficacy and toxicity of drugs, with special concerns of TCM. Copyright © 2018 Elsevier Ltd. All rights reserved.

Toxic Shock Syndrome Toxin-1-Mediated Toxicity Inhibited by Neutralizing Antibodies Late in the Course of Continual in Vivo and in Vitro Exposure

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Norbert Stich

2014-05-01

Full Text Available Toxic shock syndrome (TSS results from the host’s overwhelming inflammatory response and cytokine storm mainly due to superantigens (SAgs. There is no effective specific therapy. Application of immunoglobulins has been shown to improve the outcome of the disease and to neutralize SAgs both in vivo and in vitro. However, in most experiments that have been performed, antiserum was either pre-incubated with SAg, or both were applied simultaneously. To mirror more closely the clinical situation, we applied a multiple dose (over five days lethal challenge in a rabbit model. Treatment with toxic shock syndrome toxin 1 (TSST-1 neutralizing antibody was fully protective, even when administered late in the course of the challenge. Kinetic studies on the effect of superantigen toxins are scarce. We performed in vitro kinetic studies by neutralizing the toxin with antibodies at well-defined time points. T-cell activation was determined by assessing T-cell proliferation (3H-thymidine incorporation, determination of IL-2 release in the cell supernatant (ELISA, and IL-2 gene activation (real-time PCR (RT-PCR. Here we show that T-cell activation occurs continuously. The application of TSST-1 neutralizing antiserum reduced IL-2 and TNFα release into the cell supernatant, even if added at later time points. Interference with the prolonged stimulation of proinflammatory cytokines is likely to be in vivo relevant, as postexposure treatment protected rabbits against the multiple dose lethal SAg challenge. Our results shed new light on the treatment of TSS by specific antibodies even at late stages of exposure.

Lung toxicity determination by in vitro exposure at the air liquid interface with an integrated online dose measurement

International Nuclear Information System (INIS)

Muelhopt, Sonja; Paur, H-R; Diabate, S; Weiss, C; Krebs, T

2009-01-01

Epidemiological studies show an association between the concentration of ultrafine particles in the atmosphere and the rate of mortality or morbidity due to respiratory and cardiovascular diseases. For the quantitative assessment of the toxicity of airborne nanoparticles the dose-response relationship is tested in in vitro test systems using bioassays of cell cultures as sensor. For the air-liquid interface exposure of cell cultures towards aerosols the Karlsruhe exposure system was developed. The human lung cell cultures are exposed in VITROCELL (registered) system modules with a constant flow of the conditioned aerosol. After exposure the cells are analyzed to measure the biological responses such as viability, inflammatory or oxidative stress. For the determination of the dose response relationship the accurate knowledge of the deposited particle mass is essential. A new online method is developed in the Karlsruhe exposure system: the sensor of a quartz crystal microbalance is placed in an exposure chamber instead of the membrane insert and exposed to the aerosol in the same way as the cell cultures. The deposited mass per area unit is monitored as a function of exposure time showing a linear relationship for a constant aerosol flow with defined particle concentration. A comparison of this new dose signal to a dosimetry method using fluorescein sodium particles shows a very good correlation between the sensor signal of the quartz crystal microbalance and the deposited mass on the membranes shown by spectroscopy. This system for the first time provides an online dose measurement for in vitro experiments with nanoparticles.

Evaluation of the toxic effect of endocrine disruptor Bisphenol A (BPA) in the acute and chronic toxicity tests with Pomacea lineata gastropod.

Science.gov (United States)

de Andrade, André Lucas Correa; Soares, Priscila Rafaela Leão; da Silva, Stephannie Caroline Barros Lucas; da Silva, Marília Cordeiro Galvão; Santos, Thamiris Pinheiro; Cadena, Marilia Ribeiro Sales; Soares, Pierre Castro; Cadena, Pabyton Gonçalves

2017-07-01

Bisphenol A (BPA) is a plasticizer and a risk when it interacts with organisms, and can cause changes in the development and reproduction of them. This study aimed to evaluate the effects of BPA, by acute and chronic toxicity tests with neonates and adults of Pomacea lineata. Adults and neonates were divided into groups exposed to BPA (1-20mg/L), or 17β-estradiol (1mg/L) and control in the acute and chronic toxicity tests. Behavior, heart rate, reproduction and hemolymph biochemical analysis were measured. In the acute toxicity test, the 96-h LC 50 with adults was 11.09 and with neonates was 3.14mg/L. In this test, it was observed lethargic behavior and an increase of 77.6% of aspartate aminotransferase in the adults' hemolymph (ptest, it was observed behaviors associated with reproduction, as Copulate, in the groups exposed to BPA. The results that were found in this study proved that BPA is a potentially toxic agent to Pomacea lineata according to biological parameters evaluated. These data contribute to the understanding of BPA toxic effects' in the aquatic invertebrates. Copyright © 2017 Elsevier Inc. All rights reserved.

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

In vitro toxicity and control of Meloidogyne incognita in soybean by rosemary extract

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Mônica Anghinoni Müller

2016-02-01

Full Text Available The control of nematodes in plants can be challenging, and there is a need for alternative, environmentally conscious methods for their management. The purpose of this study was to evaluate the effect of rosemary extract (Rosmarinus officinalis on the in vitro toxicity and control of Meloidogyne incognita in CD 206 and CD 215 soybean cultivars. Using an in vitro assay, 500 M. incognita eggs per plate were observed for 15 days after incubation with rosemary extract at concentrations of 1%, 5%, and 10%. Soybean plants were studied under greenhouse conditions, and starting at V3 stage, were sprayed weekly with the same concentration of rosemary extract for 64 days. Three days after the first treatment, each soybean plant was inoculated with 1800 eggs and 400 second-stage juveniles (J2. At the end of this essay, number of eggs and J2 in the roots and soil, number of galls, and the reproduction factor (RF were evaluated. Our results showed that in the in vitro assay, rosemary extract reduced the number of M. incognita eggs that hatched. Under greenhouse conditions, the CD 206 cultivar showed a 48% reduction in the number of galls, as well as fewer eggs in the soil and a lower RF. Similarly, in the CD 215 cultivar, the number of eggs was reduced and the RF was lower. These results indicate the potential for rosemary extract to control M. incognita in soybean crops.

Antioxidant, Antibacterial activity and Brine shrimp toxicity test of some Mountainous Lichens from Nepal

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Babita Paudel

2012-01-01

Full Text Available A total of twenty four lichen species belonging to six families were collected from mountainous region of Nepal. The methanol extracts of each species were tested for antimicrobial and antioxidant activitiesin vitro. It was found that extracts of twenty one lichen species were active againstB. subtilis and seven species were active againstS. aureus. Similarly, in DPPH assay, three speciesPeltigera sp.,Cladonia sp., andCanoparmelia sp. showed comparable activity with commercial standard, BHA. In ABTS+ assay, extracts ofParmoterma sp.,Ramalina sp.,Peltigera sp. andCladonia sp. showed stronger activity than ascorbic acid. The observed data after comparison with previously published reports indicated that the high altitude lichens contain stronger antioxidant and antibacterial constituents. Similarly, the methanol extracts ofHeterodermia sp. andRamalina sp. showed comparable toxicity effect with commercial standard berberine chloride indicating a potent source of anticancer drugs.

Stability and in vitro toxicity of an infliximab eye drop formulation.

Science.gov (United States)

Robert, Marie-Claude; Spurr-Michaud, Sandra; Frenette, Mathieu; Young, David; Gipson, Ilene K; Dohlman, Claes H

2014-01-01

The purpose of this study was to develop a novel 10-mg/mL infliximab eye drop, to characterize its physical and biological stability under recommended storage conditions, and to assess the formulation's toxicity to ocular surface epithelium in vitro. Infliximab (10 mg/mL) was reconstituted using equal volumes of sterile water and 1% carboxymethylcellulose artificial tears. Aliquots were stored in either a 4 degrees C refrigerator or -20 degrees C freezer for up to 45 days. Physical stability was assessed through monitoring the solution's appearance, pH, ultraviolet-visible-near infrared absorbance and scattering, as well as protein gel electrophoresis. Biological stability was assayed through binding to tumor necrosis factor-alpha using an enzyme-linked immunosorbent assay. In vitro cytotoxicity to human corneal-limbal epithelial cells was examined following a 4-hour exposure to the study drug. Refrigerated and frozen infliximab eye drops remained clear and colorless for the duration of study. The formulation's pH (7.0) was comparable to that of the artificial tear vehicle alone. Low levels of ultraviolet-visible-near infrared light absorbance and scattering established the lack of protein precipitate after refrigeration or freezing. Protein gel electrophoresis performed under reducing conditions revealed the presence of two main protein bands of approximately 50 kDa and 25 kDa, representing immunoglobulin G heavy and light chains. The migration pattern of the proteins did not change under the different storage conditions and between day 10 and 45 after formulation. Infliximab binding to tumor necrosis factor-alpha remained stable for up to 45 days, with conservation of 101% and 102% of its initial binding activity when refrigerated or frozen, respectively. In vitro human corneal-limbal epithelial cultures showed no increase in cytotoxicity with infliximab treatment when compared to vehicle and culture media controls (P > 0.05). Infliximab can be formulated as an

40 CFR 798.5375 - In vitro mammalian cytogenetics.

Science.gov (United States)

2010-07-01

... SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Genetic Toxicity § 798.5375 In vitro... time is selected, supporting data for the harvest time should be presented in such a study. (ii) For..., fixation and staining. (7) Analysis. Slides shall be coded before analysis. In human lymphocytes, only...

In honor of the Teratology Society's 50th anniversary: The role of Teratology Society members in the development and evolution of in vivo developmental toxicity test guidelines.

Science.gov (United States)

Tyl, Rochelle W

2010-06-01

Members of the Teratology Society (established in 1960) were involved in the first governmental developmental and reproductive toxicity testing guidelines (1966) by FDA following the thalidomide epidemic, followed by other national and international governmental testing guidelines. The Segment II (developmental toxicity) study design, described in rodents and rabbits, has evolved with additional enhanced endpoints and better descriptions, mechanistic insights, range-finding studies, and toxico/pharmacokinetic ADME information (especially for pharmaceuticals). Society members were also involved in the development of the current screening assays and tests for endocrine disruptors (beginning in 1996) and are now involved with developing new testing guidelines (e.g., the extended one-generation protocol), and evaluating the current test guidelines and new initiatives under ILSI/HESI sponsorship. New initiatives include ToxCast from the U.S. EPA to screen, prioritize, and predict toxic chemicals by high throughput and high-content in vitro assays, bioinformation, and modeling to reduce (or eliminate) in vivo whole animal studies. Our Society and its journal have played vital roles in the scientific and regulatory accomplishments in birth defects research over the past 50 years and will continue to do so in the future. Happy 50th anniversary! (c) 2010 Wiley-Liss, Inc.

Ravuconazole self-emulsifying delivery system: in vitro activity against Trypanosoma cruzi amastigotes and in vivo toxicity

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Spósito PA

2017-05-01

Full Text Available Pollyanna Álvaro Spósito,1 Ana Lia Mazzeti,1,2 Caroline de Oliveira Faria,1 Julio A Urbina,3 Gwenaelle Pound-Lana,1 Maria Terezinha Bahia,2 Vanessa Furtado Mosqueira1 1Laboratory of Pharmaceutics and Nanotechnology Research, Pharmacy Department, School of Pharmacy, Universidade Federal de Ouro Preto, Minas Gerais, Brazil; 2Parasite Diseases Research Laboratory, NUPEB, Medical School, Universidade Federal de Ouro Preto, MG, Brazil; 3Venezuelan Institute for Scientific Research, Apartado, Caracas, Venezuela Abstract: Self-emulsifying drug delivery systems (SEDDSs are lipid-based anhydrous formulations composed of an isotropic mixture of oil, surfactant, and cosurfactants usually presented in gelatin capsules. Ravuconazole (Biopharmaceutics Classification System [BCS] Class II is a poorly water-soluble drug, and a SEDDS type IIIA was designed to deliver it in a predissolved state, improving dissolution in gastrointestinal fluids. After emulsification, the droplets had mean hydrodynamic diameters <250 nm, zeta potential values in the range of −45 mV to −57 mV, and showed no signs of ravuconazole precipitation. Asymmetric flow field-flow fractionation with dynamic and multiangle laser light scattering was used to characterize these formulations in terms of size distribution and homogeneity. The fractograms obtained at 37°C showed a polydisperse profile for all blank and ravuconazole–SEDDS formulations but no large aggregates. SEDDS increased ravuconazole in vitro dissolution extent and rate (20% compared to free drug (3% in 6 h. The in vivo toxicity of blank SEDDS comprising Labrasol® surfactant in different concentrations and preliminary safety tests in repeated-dose oral administration (20 days showed a dose-dependent Labrasol toxicity in healthy mice. Ravuconazole–SEDDS at low surfactant content (10%, v/v in Trypanosoma cruzi-infected mice was safe during the 20-day treatment. The anti-T. cruzi activity of free ravuconazole

AMMONIUM TOXICITY AND NITRATE RESPONSE OF AXENICALLY GROWN DACTYLORHIZA-INCARNATA SEEDLINGS

NARCIS (Netherlands)

DIJK, E; ECK, N

1995-01-01

The response to ammonium- and nitrate-nitrogen of seedlings of the calcicole orchid species Dactylorhiza incarnata (L.) Soo was tested in axenic in vitro culture of c. 3-month-old protocorms. A pronounced toxicity of ammonium ions was observed. Seedlings raised from plants of a coastal population

Discovering less toxic ionic liquids by using the Microtox® toxicity test.

Science.gov (United States)

Hernández-Fernández, F J; Bayo, J; Pérez de los Ríos, A; Vicente, M A; Bernal, F J; Quesada-Medina, J

2015-06-01

New Microtox® toxicity data of 16 ionic liquids of different cationic and anionic composition were determined. The ionic liquids 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate, [BMPyr(+)][TFO(-)], 1-butyl-1-methylpyrrolidinium chloride, [BMPyr(+)][Cl(-)], hydroxypropylmethylimidazolium fluoroacetate, [HOPMIM(+)][FCH2COO(-)], and hydroxypropylmethylimidazolium glycolate [HOPMIM(+)][glycolate(-)] were found to be less toxic than conventional organic solvent such as chloroform or toluene, accoding the Microtox® toxicity assays. The toxicity of pyrrolidinium cation was lower than the imidazolium and pyridinium ones. It was found that the inclusion of an hydroxyl group in the alkyl chain length of the cation also reduce the toxicity of the ionic liquid. To sum up, the Microtox® toxicity assays can be used as screening tool to easily determined the toxicity of a wide range of ionic liquids and the toxicity data obtained could allow the obtention of structure-toxicity relationships to design less toxic ionic liquids. Copyright © 2015 Elsevier Inc. All rights reserved.

Allium -test as a tool for toxicity testing of environmental radioactive-chemical mixtures

International Nuclear Information System (INIS)

Oudalova, A A; Pyatkova, S V; Geras’kin, S A; Dikareva, N S

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium -test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium -test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds. (paper)

Development of a chronic sediment toxicity test for marine benthic amphipods

International Nuclear Information System (INIS)

DeWitt, T.H.; Redmond, M.S.; Sewall, J.E.; Swartz, R.C.

1992-12-01

The results of the research effort culminated in the development of a research method for assessing the chronic toxicity of contaminated marine and estuarine sediments using the benthic amphipod, Leptocheirus plumulosus. The first chapter describes the efforts at collecting, handling, and culturing four estuarine amphipods from Chesapeake Bay, including L. plumulosus. This chapter includes maps of the distribution and abundance of these amphipods within Chesapeake Bay and methodologies for establishing cultures of amphipods which could be readily adopted by other laboratories. The second chapter reports the development of acute and chronic sediment toxicity test methods for L. plumulosus, its sensitivity to non-contaminant environmental variables, cadmium, two polynuclear aromatic hydrocarbons, and contaminated sediment from Baltimore Harbor, MD. The third chapter reports the authors attempts to develop a chronic sediment toxicity test with Ampelisca abdita

Acute toxicity profiling of the ethyl acetate fraction of Swietenia macrophylla seeds and in-vitro neuroprotectio

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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.

Hepatocyte-based in vitro model for assessment of drug-induced cholestasis

Energy Technology Data Exchange (ETDEWEB)

Chatterjee, Sagnik, E-mail: Sagnik.Chatterjee@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium); Richert, Lysiane, E-mail: l.richert@kaly-cell.com [KaLy-Cell, 20A rue du Général Leclerc, 67115 Plobsheim (France); Augustijns, Patrick, E-mail: Patrick.Augustijns@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium); Annaert, Pieter, E-mail: Pieter.Annaert@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium)

2014-01-01

Early detection of drug-induced cholestasis remains a challenge during drug development. We have developed and validated a biorelevant sandwich-cultured hepatocytes- (SCH) based model that can identify compounds causing cholestasis by altering bile acid disposition. Human and rat SCH were exposed (24–48 h) to known cholestatic and/or hepatotoxic compounds, in the presence or in the absence of a concentrated mixture of bile acids (BAs). Urea assay was used to assess (compromised) hepatocyte functionality at the end of the incubations. The cholestatic potential of the compounds was expressed by calculating a drug-induced cholestasis index (DICI), reflecting the relative residual urea formation by hepatocytes co-incubated with BAs and test compound as compared to hepatocytes treated with test compound alone. Compounds with clinical reports of cholestasis, including cyclosporin A, troglitazone, chlorpromazine, bosentan, ticlopidine, ritonavir, and midecamycin showed enhanced toxicity in the presence of BAs (DICI ≤ 0.8) for at least one of the tested concentrations. In contrast, the in vitro toxicity of compounds causing hepatotoxicity by other mechanisms (including diclofenac, valproic acid, amiodarone and acetaminophen), remained unchanged in the presence of BAs. A safety margin (SM) for drug-induced cholestasis was calculated as the ratio of lowest in vitro concentration for which was DICI ≤ 0.8, to the reported mean peak therapeutic plasma concentration. SM values obtained in human SCH correlated well with reported % incidence of clinical drug-induced cholestasis, while no correlation was observed in rat SCH. This in vitro model enables early identification of drug candidates causing cholestasis by disturbed BA handling. - Highlights: • Novel in vitro assay to detect drug-induced cholestasis • Rat and human sandwich-cultured hepatocytes (SCH) as in vitro models • Cholestatic compounds sensitize SCH to toxic effects of accumulating bile acids • Drug

Hepatocyte-based in vitro model for assessment of drug-induced cholestasis

International Nuclear Information System (INIS)

Chatterjee, Sagnik; Richert, Lysiane; Augustijns, Patrick; Annaert, Pieter

2014-01-01

Early detection of drug-induced cholestasis remains a challenge during drug development. We have developed and validated a biorelevant sandwich-cultured hepatocytes- (SCH) based model that can identify compounds causing cholestasis by altering bile acid disposition. Human and rat SCH were exposed (24–48 h) to known cholestatic and/or hepatotoxic compounds, in the presence or in the absence of a concentrated mixture of bile acids (BAs). Urea assay was used to assess (compromised) hepatocyte functionality at the end of the incubations. The cholestatic potential of the compounds was expressed by calculating a drug-induced cholestasis index (DICI), reflecting the relative residual urea formation by hepatocytes co-incubated with BAs and test compound as compared to hepatocytes treated with test compound alone. Compounds with clinical reports of cholestasis, including cyclosporin A, troglitazone, chlorpromazine, bosentan, ticlopidine, ritonavir, and midecamycin showed enhanced toxicity in the presence of BAs (DICI ≤ 0.8) for at least one of the tested concentrations. In contrast, the in vitro toxicity of compounds causing hepatotoxicity by other mechanisms (including diclofenac, valproic acid, amiodarone and acetaminophen), remained unchanged in the presence of BAs. A safety margin (SM) for drug-induced cholestasis was calculated as the ratio of lowest in vitro concentration for which was DICI ≤ 0.8, to the reported mean peak therapeutic plasma concentration. SM values obtained in human SCH correlated well with reported % incidence of clinical drug-induced cholestasis, while no correlation was observed in rat SCH. This in vitro model enables early identification of drug candidates causing cholestasis by disturbed BA handling. - Highlights: • Novel in vitro assay to detect drug-induced cholestasis • Rat and human sandwich-cultured hepatocytes (SCH) as in vitro models • Cholestatic compounds sensitize SCH to toxic effects of accumulating bile acids • Drug

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.

Reproductive toxicity assessment of surface water of the Tai section of the Yangtze River, China by in vitro bioassays coupled with chemical analysis

International Nuclear Information System (INIS)

Wang Xiaoyi; Wu Jiang; Hao Yingqun; Zhu Bingqing; Shi Wei; Hu Guanjiu; Han Xiaodong; Giesy, John P.; Yu Hongxia

2011-01-01

Reproductive toxicity of organic extracts of the surface water from the Tai section of the Yangtze River was assessed by in vitro cytotoxity assays and selected persistent organic pollutants including PCBs, OCPs and PAHs were quantified by instrumental analysis. Eleven of the US EPA priority PAHs were detected. Individual PAHs were found to range from 0.7 to 20 ng/L. Concentrations of BaP did not exceed the national drinking water source quality standard of China. However, a 286-fold concentrated organic extract induced significant reproductive toxicity in adult male rats. The morphology of cells, MTT assay and LDH release assay were all affected by exposure to the organic extracts of water. The results of the reproductive toxicity indicated that PAHs posed the greatest risk of the chemicals studied. The compounds present in the water could be bioconcentrated and result in adverse effects. - Highlights: → Only 11 PAHs of US EPA priority PAHs were detected in surface water the Yangtze River. → Level of BaP didn't exceed national drinking water source quality standard of China. → 286-fold concentrated organic extracts induced great reproductive toxicity in rats. → PAHs posed the greatest risk of the chemicals studied. → The compounds in the water could be bioconcentrated and result in adverse effects. - In vitro bioassay responses observed in Yangtze River source water extracts showed great reproductive toxicity, and PAHs were responsible.

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.

In vitro and ex vivo testing of tenofovir shows it is effective as an HIV-1 microbicide.

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Lisa C Rohan

2010-02-01

Full Text Available Tenofovir gel has entered into clinical trials for use as a topical microbicide to prevent HIV-1 infection but has no published data regarding pre-clinical testing using in vitro and ex vivo models. To validate our findings with on-going clinical trial results, we evaluated topical tenofovir gel for safety and efficacy. We also modeled systemic application of tenofovir for efficacy.Formulation assessment of tenofovir gel included osmolality, viscosity, in vitro release, and permeability testing. Safety was evaluated by measuring the effect on the viability of vaginal flora, PBMCs, epithelial cells, and ectocervical and colorectal explant tissues. For efficacy testing, PBMCs were cultured with tenofovir or vehicle control gels and HIV-1 representing subtypes A, B, and C. Additionally, polarized ectocervical and colorectal explant cultures were treated apically with either gel. Tenofovir was added basolaterally to simulate systemic application. All tissues were challenged with HIV-1 applied apically. Infection was assessed by measuring p24 by ELISA on collected supernatants and immunohistochemistry for ectocervical explants. Formulation testing showed the tenofovir and vehicle control gels were >10 times isosmolar. Permeability through ectocervical tissue was variable but in all cases the receptor compartment drug concentration reached levels that inhibit HIV-1 infection in vitro. The gels were non-toxic toward vaginal flora, PBMCs, or epithelial cells. A transient reduction in epithelial monolayer integrity and epithelial fracture for ectocervical and colorectal explants was noted and likely due to the hyperosmolar nature of the formulation. Tenofovir gel prevented HIV-1 infection of PBMCs regardless of HIV-1 subtype. Topical and systemic tenofovir were effective at preventing HIV-1 infection of explant cultures.These studies provide a mechanism for pre-clinical prediction of safety and efficacy of formulated microbicides. Tenofovir was effective

Testing of CFC replacement fluids for arc-induced toxic by-products

Energy Technology Data Exchange (ETDEWEB)

Cravey, W.R.; Goerz, D.A.; Hawley-Fedder, R.A.

1993-06-01

The authors have developed a unique test-stand for quantifying the generation of perfluoroisobutylene (PFIB) in chlorofluorocarbon (CFC) replacement fluids when they are subjected to high electrical stress/breakdown environments. PFIB is an extremely toxic gas with a threshold limit value of 10 ppbv as set by the American Conference of Governmental Industrial Hygienists. They have tested several new fluids from various manufacturers for their potential to generate PFIB. Their goal is to determine breakdown characteristics and quantify toxic by-products of these replacement fluids to determine a safe, usable alternative for present CFC`s.

THE ROLE OF INORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING

Science.gov (United States)

Effluent toxicity testing methods have been well defined, but to a large part have not attempted to segregate the effects of active ionic concentrations and ion imbalances upon test and species performances. The role that various total dissolved solids in effluents have on regula...

Dredged Material Evaluations: Review of Zooplankton Toxicity Test Methods for Marine Water Quality Evaluations

Science.gov (United States)

2016-09-01

term impacts of the DM while settling through the water column (elutriate toxicity tests), and long-term toxicity (whole sediment toxicity tests) and...elutriates are prepared according to guidance (USEPA/USACE 1991; 1998) by mixing sediment and site water and allowing settling for prescribed periods...of water and waste water . 17th ed. Washington, DC: APHA. Arnold, W. R., R. L. Diamond, and D. S. Smith. 2010a. The effects of salinity, pH, and

Reproductive toxicity testing of vaccines

International Nuclear Information System (INIS)

Verdier, Francois; Barrow, Paul C.; Burge, Joeelle

2003-01-01

Vaccines play a major role in the prevention of human birth defects by protecting the pregnant woman from teratogenic or otherwise harmful infections. Until now, it has not been common practice to perform preclinical developmental toxicity tests for new vaccines. Despite the excellent safety record of vaccines, increased attention is now being given to the feasibility of screening new vaccines for developmental hazards in animals before their use in humans. Contrary to previous assumptions, many vaccines are now given to potentially pregnant women. Any new components of the vaccine formulation (adjuvants, excipients, stabilisers, preservatives, etc...) could also be tested for influences on development, although based on past experience the risks are limited by the very low dosages used. The conferred immunity following vaccination lasts for several years. Therefore, the developing conceptus may theoretically be exposed to the induced antibodies and/or sensitised T-cells, even if the pregnant woman was last vaccinated during childhood (particularly if she encounters the antigen during pregnancy through exposure to infection). However, it should be kept in mind that viral or bacterial infections represent a higher risk for a pregnant woman than the potential adverse effects related to vaccination or the associated immune response. Non-clinical safety studies may be employed as an aid for hazard identification. In these studies interactions of the vaccine with the maternal immune system or with the developmental systems of the offspring are considered. Post-natal examinations are necessary to detect all possible manifestations of developmental toxicity, such as effects on the immune system. Species selection for the preclinical studies is based on immunogenicity to the vaccine and the relative timing and rate of transfer of maternal antibodies to the offspring. A single study design is proposed for the pre- and post-natal developmental assessments of vaccines in

Development of an in vitro test battery for assessing chemical effects on bovine germ cells under the ReProTect umbrella

International Nuclear Information System (INIS)

Lazzari, Giovanna; Tessaro, Irene; Crotti, Gabriella; Galli, Cesare; Hoffmann, Sebastian; Bremer, Susanne; Pellizzer, Cristian

2008-01-01

Current European legislation for the registration and authorisation of chemicals (REACH) will require a dramatic increase in the use of animals for reproductive toxicity testing. Since one objective of REACH is to use vertebrates only as last resort, the development and validation of alternative methods is urgently needed. For this purpose ReProTect, an integrated research project funded by the European Union, joining together 33 partners with complementary expertise in reproductive toxicology, was designed. The study presented here describes a battery of two tests developed within ReProTect. The objective of these tests is the detection of chemical effects during the processes of oocyte maturation and fertilisation in a bovine model. The corresponding toxicological endpoints are the reaching of metaphase II and the formation of the pronuclei respectively. Fifteen chemicals have been tested (Benzo[a]pyrene, Busulfan, Butylparaben, Cadmium Chloride, Carbendazim, Cycloheximide, Diethylstilbestrol, Genistein, Ionomycin, Ketoconazole, Lindane, Methylacetoacetate, Mifepristone, Nocodazole and DMSO as solvent) demonstrating high intra-laboratory reproducibility of the tests. Furthermore, the responses obtained in both tests, for several substances, had a good correlation with the available in vivo and in vitro data. These tests therefore, could predictably become part of an integrated testing strategy that combines the bovine models with additional in vitro tests, in order to predict chemical hazards on mammalian fertility

Adverse reactions to cosmetics and methods of testing.

Science.gov (United States)

Nigam, P K

2009-01-01

Untoward reactions to cosmetics, toiletries, and topical applications are the commonest single reason for hospital referrals with allergic contact dermatitis. In most cases, these are only mild or transient and most reactions being irritant rather than allergic in nature. Various adverse effects may occur in the form of acute toxicity, percutaneous absorption, skin irritation, eye irritation, skin sensitization and photosensitization, subchronic toxicity, mutagenicity/genotoxicity, and phototoxicity/photoirritation. The safety assessment of a cosmetic product clearly depends upon how it is used, since it determines the amount of substance which may be ingested, inhaled, or absorbed through the skin or mucous membranes. Concentration of ingredients used in the different products is also important. Various test procedures include in vivo animal models and in vitro models, such as open or closed patch test, in vivo skin irritation test, skin corrosivity potential tests (rat skin transcutaneous electrical resistance test, Episkin test), eye irritation tests (in vivo eye irritancy test and Draize eye irritancy test), mutagenicity/genotoxicity tests (in vitro bacterial reverse mutation test and in vitro mammalian cell chromosome aberration test), and phototoxicity/photoirritation test (3T3 neutral red uptake phototoxicity test). Finished cosmetic products are usually tested in small populations to confirm the skin and mucous membrane compatibility, and to assess their cosmetic acceptability.

In vitro test for pyrogenes in radiopharmaceuticals

Energy Technology Data Exchange (ETDEWEB)

Jovanovic, V; Zmbova, B; Bzenic, J [Institut za Nuklearne Nauke Boris Kidric, Belgrade (Yugoslavia); Berkes, J [Institut za Biohemije, Belgrade (Yugoslavia)

1978-05-01

Procedure and results of determination of pyrogenic substances in radiopharmaceutical preparations by an in vitro method based on the reaction between bacterial endotoxine and Limulus Amebocyte Lysate are presented. The advantage of this method as compared to the test in experimental animals performed so far has also been analyzed and proved by the fact that it enables avoidance of introduction of radioactive materials in experimental animals and of radiation effects on the results obtained in efficiency studies. The in vitro method is a quick one and requires only small quantities of the radiopharmaceutical preparation to be examined.

40 CFR 799.9355 - TSCA reproduction/developmental toxicity screening test.

Science.gov (United States)

2010-07-01

... developmental defects should not be used. Healthy virgin animals, not subjected to previous experimental..., except legal holidays. (1) OECD (1995). Reproduction/Developmental Toxicity Screening Test, OECD 421...

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

2009-10-01

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.

Enhancing the applicability and predictability of the embryonic stem cell test for developmental toxicity

NARCIS (Netherlands)

de Jong, E.

2012-01-01

Within the full risk assessment of a chemical, developmental toxicity testing is one of the endpoints that require the highest percentage of experimental animals. With the high number of experimental animals, cost and time involved in in vivo developmental toxicity testing there is an urgent need

In vivo and in vitro dermal penetration of lipophilic and hydrophilic pesticides in mice

International Nuclear Information System (INIS)

Grissom, R.E. Jr.; Brownie, C.; Guthrie, F.E.

1987-01-01

Dermal absorption is a major portal of entry for a wide variety of potentially toxic substances. In vivo and in vitro investigations assessing penetration of topically applied xenobiotics using both human and other animals have been conducted. Current ethical considerations have drastically curtailed the testing of xenobiotics in human volunteers; consequently, dermal penetration in humans is usually estimated from in vivo tests in animals and in vitro tests using either human or animal skin. In order for in vitro penetration results to be meaningful, there needs to be close relationship with in vivo data. The objective of the present study was to investigate the relationship between in vivo and in vitro penetration of both hydrophilic and lipophilic 14 C-labelled compounds in mice

Use of higher plants as screens for toxicity assessment.

Science.gov (United States)

Kristen, U

1997-01-01

This review deals with the use of entire plants, seedlings, cell suspension cultures and pollen tubes for the estimation of potential toxicity in the environment, and for risk assessment of chemicals and formulations of human relevance. It is shown that the roots of onions and various crop seedlings, as well as in vitro growing pollen tubes of some mono- and dicotyledonous plants, are most frequently used to obtain toxicity data by determination of root and tube growth inhibition. Both roots and pollen tubes are chloroplast free, non-photosynthetic systems and, therefore, with regard to their cytotoxic reactions are closer to vertebrate tissues and cells than are chloroplast-containing plant organs. Root tips and anthers of flower buds are shown to be applicable to genotoxicity screening by microscopic analysis of mitotic or meiotic aberrations during cell division or microspore development, respectively. The processes of mitosis and meiosis are similar in plants and animals. Therefore, meristematic and sporogenic tissues of plants generally show patterns of cytotoxic response similar to those of embryogenic and spermatogenic tissues of vertebrates. The suitability of root tips, cell suspensions and pollen tubes for the investigation of mechanisms of toxic action and for the analysis of structure-activity relationships is also demonstrated. Two plant-based assays, the Allium test and the pollen tube growth test, both currently being evaluated alongside with established mammalian in vivo and in vitro protocols, are emphasized with regard to their potential use as alternatives to animal in vivo toxicity tests. For both assays, preliminary results indicate that the tips of growing roots and the rapidly elongating pollen tubes of certain higher plant species are as reliable as mammalian cell lines for detecting basal cytotoxicity. It is suggested that seeds and pollen grains, in particular, provide easily storable and convenient systems for inexpensive, relatively

Tests for oil/dispersant toxicity: In situ laboratory assays

International Nuclear Information System (INIS)

Wright, D.A.; Coelho, G.M.; Aurand, D.V.

1995-01-01

As part of its readiness program in oil spill response, the Marine Pollution Control Unit (MPCU), Department of Transport, U.K. conducts annual field trials in the North Sea, approximately 30 nautical miles from the southeast coast of England. The trials take the form of controlled releases of crude oil or Medium Fuel/Gas Oil mix (MFO), with and without the application of Corexit 9527 dispersant. In 1994 and 1995 the authors conducted a series of in situ toxicity bioassays in association with these spills with included 48h LC50 tests for turbot (Scophthalmus maximus) and oyster (Crassostrea gigas) larvae, a 48 h oyster (C. gigas) embryonic development test and two full life-cycle assays using the copepods Acartia tonsa and Tisbe battagliai. Tests were also conducted in the Chesapeake Bay laboratory using estuarine species including the copepod Eurytemora affinis and the inland silverside Menidia beryllina. Here, the authors report on the results of these assays, together with 1996 in situ toxicity data resulting from Norwegian field trials in the northern North Sea

Toxic Substances Control Act test submissions database (TSCATS) - comprehensive update. Data file

International Nuclear Information System (INIS)

1993-01-01

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data is submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test is broadly defined to include case reports, episodic incidents, such as spills, and formal test study presentations. The database allows searching of test submissions according to specific chemical identity or type of study when used with an appropriate search retrieval software program. Studies are indexed under three broad subject areas: health effects, environmental effects and environmental fate. Additional controlled vocabulary terms are assigned which describe the experimental protocol and test observations. Records identify reference information needed to locate the source document, as well as the submitting organization and reason for submission of the test data

QSAR Models for Reproductive Toxicity and Endocrine Disruption Activity

Directory of Open Access Journals (Sweden)

Marjan Vračko

2010-03-01

Full Text Available Reproductive toxicity is an important regulatory endpoint, which is required in registration procedures of chemicals used for different purposes (for example pesticides. The in vivo tests are expensive, time consuming and require large numbers of animals, which must be sacrificed. Therefore an effort is ongoing to develop alternative In vitro and in silico methods to evaluate reproductive toxicity. In this review we describe some modeling approaches. In the first example we describe the CAESAR model for prediction of reproductive toxicity; the second example shows a classification model for endocrine disruption potential based on counter propagation artificial neural networks; the third example shows a modeling of relative binding affinity to rat estrogen receptor, and the fourth one shows a receptor dependent modeling experiment.

Integrating Exposure, Pharmacokinetics, And Dosimetry With In Vitro Dose-Response Data To Evaluate Chemical Risk

Science.gov (United States)

High throughput in vitro toxicity testing of hundreds to thousands of chemicals across any number of biological endpoints allows for rapidly assessing human and ecosystem health impacts, thus reducing resources associated with traditional animal testing. In order to apply these i...

Bringing in vitro analysis closer to in vivo: Studying doxorubicin toxicity and associated mechanisms in 3D human microtissues with PBPK-based dose modelling.

Science.gov (United States)

Verheijen, Marcha; Schrooders, Yannick; Gmuender, Hans; Nudischer, Ramona; Clayton, Olivia; Hynes, James; Niederer, Steven; Cordes, Henrik; Kuepfer, Lars; Kleinjans, Jos; Caiment, Florian

2018-05-24

Doxorubicin (DOX) is a chemotherapeutic agent of which the medical use is limited due to cardiotoxicity. While acute cardiotoxicity is reversible, chronic cardiotoxicity is persistent or progressive, dose-dependent and irreversible. While DOX mechanisms of action are not fully understood yet, 3 toxicity processes are known to occur in vivo: cardiomyocyte dysfunction, mitochondrial dysfunction and cell death. We present an in vitro experimental design aimed at detecting DOX-induced cardiotoxicity by obtaining a global view of the induced molecular mechanisms through RNA-sequencing. To better reflect the in vivo situation, human 3D cardiac microtissues were exposed to physiologically-based pharmacokinetic (PBPK) relevant doses of DOX for 2 weeks. We analysed a therapeutic and a toxic dosing profile. Transcriptomics analysis revealed significant gene expression changes in pathways related to "striated muscle contraction" and "respiratory electron transport", thus suggesting mitochondrial dysfunction as an underlying mechanism for cardiotoxicity. Furthermore, expression changes in mitochondrial processes differed significantly between the doses. Therapeutic dose reflects processes resembling the phenotype of delayed chronic cardiotoxicity, while toxic doses resembled acute cardiotoxicity. Overall, these results demonstrate the capability of our innovative in vitro approach to detect the three known mechanisms of DOX leading to toxicity, thus suggesting its potential relevance for reflecting the patient situation. Our study also demonstrated the importance of applying physiologically relevant doses during toxicological research, since mechanisms of acute and chronic toxicity differ. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

FDA toxicity databases and real-time data entry

International Nuclear Information System (INIS)

Arvidson, Kirk B.

2008-01-01

Structure-searchable electronic databases are valuable new tools that are assisting the FDA in its mission to promptly and efficiently review incoming submissions for regulatory approval of new food additives and food contact substances. The Center for Food Safety and Applied Nutrition's Office of Food Additive Safety (CFSAN/OFAS), in collaboration with Leadscope, Inc., is consolidating genetic toxicity data submitted in food additive petitions from the 1960s to the present day. The Center for Drug Evaluation and Research, Office of Pharmaceutical Science's Informatics and Computational Safety Analysis Staff (CDER/OPS/ICSAS) is separately gathering similar information from their submissions. Presently, these data are distributed in various locations such as paper files, microfiche, and non-standardized toxicology memoranda. The organization of the data into a consistent, searchable format will reduce paperwork, expedite the toxicology review process, and provide valuable information to industry that is currently available only to the FDA. Furthermore, by combining chemical structures with genetic toxicity information, biologically active moieties can be identified and used to develop quantitative structure-activity relationship (QSAR) modeling and testing guidelines. Additionally, chemicals devoid of toxicity data can be compared to known structures, allowing for improved safety review through the identification and analysis of structural analogs. Four database frameworks have been created: bacterial mutagenesis, in vitro chromosome aberration, in vitro mammalian mutagenesis, and in vivo micronucleus. Controlled vocabularies for these databases have been established. The four separate genetic toxicity databases are compiled into a single, structurally-searchable database for easy accessibility of the toxicity information. Beyond the genetic toxicity databases described here, additional databases for subchronic, chronic, and teratogenicity studies have been prepared

Development of a suitable test method for evaluating the toxicity of contaminated soils to earthworms in Canada

Energy Technology Data Exchange (ETDEWEB)

Stephenson, G.L. [Univ. of Guelph, Ontario (Canada); Scroggins, R. [Environment Canada, Gloucester, Ontario (Canada). Method Development and Application Section

1995-12-31

Environment Canada has embarked on a five year program to develop, standardize, and validate a battery of soil toxicity tests which can be used to assess the relative toxicity of contaminants in soils to terrestrial organisms. These tests must be applicable to soil conditions typically found in Canadian environments and the test species must be representative of the species of soil invertebrates or plants inhabiting soil ecosystems in Canada. One of the toxicity tests being developed is designed to assess the toxicity of contaminated soils to earthworms. Five of the potential test species belong to the Lumbricidae family and include the Canadian worm (Allobophora calignosa/Aporrectodea tuberculate), the European bark worm (Dendrodtilus rubidus (rubida)), the pink soil worm (Eisenia rosea), the red marsh worm (Lumbricus rubellus), and the Canadian night crawler or dew worm (Lumbricus terrestris). The sixth species, the white pot worm (Enchytraeus albidus), belongs to the Enchytraeidae family. Further assessment reduced the number of representative species to three. Most earthworm test methods have been developed to assess the toxicity of chemically-spiked artificial soils to Eisenia fetida or E. andrei. Test methods have also been developed to assess the relative toxicity of contaminated soils from hazardous waste sites. Comparative acute toxicity data for three species of earthworm exposed to a hydrocarbon contamination will be presented. Comparative toxicity data for the same three species of earthworm will also be presented using test procedures and conditions that have been modified to accommodate biological differences among the species of earthworm. Recommendations regarding test design, methods, and conditions optimal for each test species will be summarized and discussed with respect to the precision of test results.

Estimation of toxicity using the Toxicity Estimation Software Tool (TEST)

Science.gov (United States)

Tens of thousands of chemicals are currently in commerce, and hundreds more are introduced every year. Since experimental measurements of toxicity are extremely time consuming and expensive, it is imperative that alternative methods to estimate toxicity are developed.

Molecular ecotoxicology of nanosilver guided using in vitro prognosis

DEFF Research Database (Denmark)

Hayashi, Yuya; Heckmann, Lars-Henrik; Engelmann, Péter

2012-01-01

To study the molecular and cellular basis of silver nanoparticle (AgNP) toxicity, we here used a recently established in vitro model of earthworm coelomocytes in comparison to the conventional in vivo molecular ecotoxicology approach. Compared to the latter where the test organisms are exposed...... to NPs of interest held in an environmental matrix, in vitro models benefit from the ease of controlling exposure conditions in a defined set of biochemical milieus that NPs may encounter. The AgNPs tested in the present study originated from the same source, but to enhance the colloidal stability...... in the in vitro test media the NPs were pre-treated with serum proteins. In addition to physical characterisation of AgNPs, the active silver ion fraction was measured (in serum-supplemented cell culture medium and in soil pore-water). Using flow cytometry and atomic absorption spectrophotometry, we show...

Parallel comparative studies on toxicity of quantum dots synthesized and surface engineered with different methods in vitro and in vivo

Directory of Open Access Journals (Sweden)

Liu F

2017-07-01

Full Text Available Fengjun Liu1,* Wen Ye1,* Jun Wang2 Fengxiang Song1 Yingsheng Cheng3 Bingbo Zhang21Department of Radiology, Shanghai Public Health Clinical Center, 2Institute of Photomedicine, Shanghai Skin Disease Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, 3Department of Radiology, Shanghai Sixth People’s Hospital, Shanghai Jiao Tong University, Shanghai, China *These authors contributed equally to this work Abstract: Quantum dots (QDs have been considered to be promising probes for biosensing, bioimaging, and diagnosis. However, their toxicity issues caused by heavy metals in QDs remain to be addressed, in particular for their in vivo biomedical applications. In this study, a parallel comparative investigation in vitro and in vivo is presented to disclose the impact of synthetic methods and their following surface modifications on the toxicity of QDs. Cellular assays after exposure to QDs were conducted including cell viability assessment, DNA breakage study in a single cellular level, intracellular reactive oxygen species (ROS receptor measurement, and transmission electron microscopy to evaluate their toxicity in vitro. Mice experiments after QD administration, including analysis of hemobiological indices, pharmacokinetics, histological examination, and body weight, were further carried out to evaluate their systematic toxicity in vivo. Results show that QDs fabricated by the thermal decomposition approach in organic phase and encapsulated by an amphiphilic polymer (denoted as QDs-1 present the least toxicity in acute damage, compared with those of QDs surface engineered by glutathione-mediated ligand exchange (denoted as QDs-2, and the ones prepared by coprecipitation approach in aqueous phase with mercaptopropionic acid capped (denoted as QDs-3. With the extension of the investigation time of mice respectively injected with QDs, we found that the damage caused by QDs to the organs can be

Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part 2. Variability of measurement parameters under toxicant-induced stress

Energy Technology Data Exchange (ETDEWEB)

Grillitsch, B.; Vogl, C.; Wytek, R.

1999-12-01

Spontaneous locomotor behavior of semiadult zebra fish (Brachydanio rerio) was recorded under sublethal short-term exposure to the anionic technical surfactant, linear alkylbenzene sulfonate (C{sub 10-13}-LAS) and cadmium in single compound tests using an automated video-monitoring and object-tracing system. Vertical position and swimming velocity in the horizontal and vertical directions were used as behavioral measurement parameters. Data were analyzed by different statistical methods. In pairwise comparisons, consistent, statistically significant, and toxicant-induced alterations of locomotor behavior were observed only for test concentrations, which also caused aspectoric symptoms of intoxication. This comparatively low sensitivity of the behavioral indication criteria was related to high variation in the measurement parameters and corresponding high, minimum detectable, statistically significant, and toxicant-induced deviations. In contrast, results obtained by regression analysis showed significant trends in locomotor activity over the range of toxicant concentrations tested. Thus, the findings support the inappropriateness of no observed effect concentrations and the lowest observed effect concentrations as summary measures of toxicity and indicate that the regression analysis approach is superior to the analysis of variance approach.

Regenerative toxicology: the role of stem cells in the development of chronic toxicities.

Science.gov (United States)

Canovas-Jorda, David; Louisse, Jochem; Pistollato, Francesca; Zagoura, Dimitra; Bremer, Susanne

2014-01-01

Human stem cell lines and their derivatives, as alternatives to the use of animal cells or cancer cell lines, have been widely discussed as cellular models in predictive toxicology. However, the role of stem cells in the development of long-term toxicities and carcinogenesis has not received great attention so far, despite growing evidence indicating the relationship of stem cell damage to adverse effects later in life. However, testing this in vitro is a scientific/technical challenge in particular due to the complex interplay of factors existing under physiological conditions. Current major research programs in stem cell toxicity are not aiming to demonstrate that stem cells can be targeted by toxicants. Therefore, this knowledge gap needs to be addressed in additional research activities developing technical solutions and defining appropriate experimental designs. The current review describes selected examples of the role of stem cells in the development of long-term toxicities in the brain, heart or liver and in the development of cancer. The presented examples illustrate the need to analyze the contribution of stem cells to chronic toxicity in order to make a final conclusion whether stem cell toxicities are an underestimated risk in mechanism-based safety assessments. This requires the development of predictive in vitro models allowing the assessment of adverse effects to stem cells on chronic toxicity and carcinogenicity.

Development of Cardiovascular and Neurodevelopmental Metrics as Sublethal Endpoints for the Fish Embryo Toxicity Test.

Science.gov (United States)

Krzykwa, Julie C; Olivas, Alexis; Jeffries, Marlo K Sellin

2018-06-19

The fathead minnow fish embryo toxicity (FET) test has been proposed as a more humane alternative to current toxicity testing methods, as younger organisms are thought to experience less distress during toxicant exposure. However, the FET test protocol does not include endpoints that allow for the prediction of sublethal adverse outcomes, limiting its utility relative to other test types. Researchers have proposed the development of sublethal endpoints for the FET test to increase its utility. The present study 1) developed methods for previously unmeasured sublethal metrics in fathead minnows (i.e., spontaneous contraction frequency and heart rate) and 2) investigated the responsiveness of several sublethal endpoints related to growth (wet weight, length, and growth-related gene expression), neurodevelopment (spontaneous contraction frequency, and neurodevelopmental gene expression), and cardiovascular function and development (pericardial area, eye size and cardiovascular related gene expression) as additional FET test metrics using the model toxicant 3,4-dichloroaniline. Of the growth, neurological and cardiovascular endpoints measured, length, eye size and pericardial area were found to more responsive than the other endpoints, respectively. Future studies linking alterations in these endpoints to longer-term adverse impacts are needed to fully evaluate the predictive power of these metrics in chemical and whole effluent toxicity testing. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Early Combination of Material Characteristics and Toxicology Is Useful in the Design of Low Toxicity Carbon Nanofiber

Directory of Open Access Journals (Sweden)

Tore Syversen

2012-09-01

Full Text Available This paper describes an approach for the early combination of material characterization and toxicology testing in order to design carbon nanofiber (CNF with low toxicity. The aim was to investigate how the adjustment of production parameters and purification procedures can result in a CNF product with low toxicity. Different CNF batches from a pilot plant were characterized with respect to physical properties (chemical composition, specific surface area, morphology, surface chemistry as well as toxicity by in vitro and in vivo tests. A description of a test battery for both material characterization and toxicity is given. The results illustrate how the adjustment of production parameters and purification, thermal treatment in particular, influence the material characterization as well as the outcome of the toxic tests. The combination of the tests early during product development is a useful and efficient approach when aiming at designing CNF with low toxicity. Early quality and safety characterization, preferably in an iterative process, is expected to be efficient and promising for this purpose. The toxicity tests applied are preliminary tests of low cost and rapid execution. For further studies, effects such as lung inflammation, fibrosis and respiratory cancer are recommended for the more in-depth studies of the mature CNF product.

Microscale 3D Liver Bioreactor for In Vitro Hepatotoxicity Testing under Perfusion Conditions

Directory of Open Access Journals (Sweden)

Nora Freyer

2018-03-01

Full Text Available The accurate prediction of hepatotoxicity demands validated human in vitro models that can close the gap between preclinical animal studies and clinical trials. In this study we investigated the response of primary human liver cells to toxic drug exposure in a perfused microscale 3D liver bioreactor. The cellularized bioreactors were treated with 5, 10, or 30 mM acetaminophen (APAP used as a reference substance. Lactate production significantly decreased upon treatment with 30 mM APAP (p < 0.05 and ammonia release significantly increased in bioreactors treated with 10 or 30 mM APAP (p < 0.0001, indicating APAP-induced dose-dependent toxicity. The release of prostaglandin E2 showed a significant increase at 30 mM APAP (p < 0.05, suggesting an inflammatory reaction towards enhanced cellular stress. The expression of genes involved in drug metabolism, antioxidant reactions, urea synthesis, and apoptosis was differentially influenced by APAP exposure. Histological examinations revealed that primary human liver cells in untreated control bioreactors were reorganized in tissue-like cell aggregates. These aggregates were partly disintegrated upon APAP treatment, lacking expression of hepatocyte-specific proteins and transporters. In conclusion, our results validate the suitability of the microscale 3D liver bioreactor to detect hepatotoxic effects of drugs in vitro under perfusion conditions.

Microscale 3D Liver Bioreactor for In Vitro Hepatotoxicity Testing under Perfusion Conditions.

Science.gov (United States)

Freyer, Nora; Greuel, Selina; Knöspel, Fanny; Gerstmann, Florian; Storch, Lisa; Damm, Georg; Seehofer, Daniel; Foster Harris, Jennifer; Iyer, Rashi; Schubert, Frank; Zeilinger, Katrin

2018-03-15

The accurate prediction of hepatotoxicity demands validated human in vitro models that can close the gap between preclinical animal studies and clinical trials. In this study we investigated the response of primary human liver cells to toxic drug exposure in a perfused microscale 3D liver bioreactor. The cellularized bioreactors were treated with 5, 10, or 30 mM acetaminophen (APAP) used as a reference substance. Lactate production significantly decreased upon treatment with 30 mM APAP ( p < 0.05) and ammonia release significantly increased in bioreactors treated with 10 or 30 mM APAP ( p < 0.0001), indicating APAP-induced dose-dependent toxicity. The release of prostaglandin E2 showed a significant increase at 30 mM APAP ( p < 0.05), suggesting an inflammatory reaction towards enhanced cellular stress. The expression of genes involved in drug metabolism, antioxidant reactions, urea synthesis, and apoptosis was differentially influenced by APAP exposure. Histological examinations revealed that primary human liver cells in untreated control bioreactors were reorganized in tissue-like cell aggregates. These aggregates were partly disintegrated upon APAP treatment, lacking expression of hepatocyte-specific proteins and transporters. In conclusion, our results validate the suitability of the microscale 3D liver bioreactor to detect hepatotoxic effects of drugs in vitro under perfusion conditions.

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

Physiological parameters for oral delivery and in vitro testing.

Science.gov (United States)

Mudie, Deanna M; Amidon, Gordon L; Amidon, Gregory E

2010-10-04

Pharmaceutical solid oral dosage forms must undergo dissolution in the intestinal fluids of the gastrointestinal tract before they can be absorbed and reach the systemic circulation. Therefore, dissolution is a critical part of the drug-delivery process. The rate and extent of drug dissolution and absorption depend on the characteristics of the active ingredient as well as properties of the dosage form. Just as importantly, characteristics of the physiological environment such as buffer species, pH, bile salts, gastric emptying rate, intestinal motility, and hydrodynamics can significantly impact dissolution and absorption. While significant progress has been made since 1970 when the first compendial dissolution test was introduced (USP apparatus 1), current dissolution testing does not take full advantage of the extensive physiologic information that is available. For quality control purposes, where the question is one of lot-to-lot consistency in performance, using nonphysiologic test conditions that match drug and dosage form properties with practical dissolution media and apparatus may be appropriate. However, where in vitro-in vivo correlations are desired, it is logical to consider and utilize knowledge of the in vivo condition. This publication critically reviews the literature that is relevant to oral human drug delivery. Physiologically relevant information must serve as a basis for the design of dissolution test methods and systems that are more representative of the human condition. As in vitro methods advance in their physiological relevance, better in vitro-in vivo correlations will be possible. This will, in turn, lead to in vitro systems that can be utilized to more effectively design dosage forms that have improved and more consistent oral bioperformance.

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

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 �

Evaluating the toxicity of selected types of nanochemicals.

Science.gov (United States)

Kumar, Vineet; Kumari, Avnesh; Guleria, Praveen; Yadav, Sudesh Kumar

2012-01-01

Nanotechnology is a fast growing field that provides for the development of materials that have new dimensions, novel properties, and a broader array of applications. Various scientific groups are keen about this technology and are devoting themselves to the development of more, new, and better nanomaterials. In the near future, expectations are that no field will be left untouched by the magical benefits available through application of nanotechnology. Presently, there is only limited knowledge concerning the toxicological effects of NPs. However, it is now known that the toxic behavior of NPs differ from their bulk counterparts. Even NPs that have the same chemical composition differ in their toxicological properties; the differences in toxicity depend upon size, shape, and surface covering. Hence, before NPs are commercially used it is most important that they be subjected to appropriate toxicity evaluation. Among the parameters of NPs that must be evaluated for their effect on toxicity are surface charges, types of coating material, and reactivity of NPs. In this article, we have reviewed the literature pertinent to the toxicity of metal oxide NPs, metallic NPs, quantum dots (QDs), silica (SiO2) NPs, carbon nanotubes (CNTs), and certain other carbon nanomaterials (NMs). These NPs have already found a wide range of applications around the world. In vitro and in vivo studies on NPs have revealed that most are toxic to animals. However, their toxic behavior varies with their size, shape, surface charge, type of coating material and reactivity. Dose, route of administration, and exposure are critical factors that affect the degree of toxicity produced by any particular type of NP. It is for this reason that we believe a careful and rigorous toxicity testing is necessary before any NP is declared to be safe for broad use. We also believe that an agreed upon testing system is needed that can be used to suitably, accurately, and economically assess the toxicity of NPs

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, TLD in vitro , and APSD TLDin 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 TLD in vitro and APSD TLDin 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 TLD in 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, APSD TLDin vitro profiles and mass median aerodynamic diameters at the MT exit (MMAD TLDin vitro ) were determined as functions of MT geometric size across Newman's IPs. The range of mean values (n ≥ 5) for TLD in vitro and MMAD TLDin 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 TLD in vitro and APSD TLDin 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 TLD in vitro and APSD TLDin vitro may be studied using the general method described in this study.

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...... sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were the main PAH species in the SIDS extractable fraction of road dust, as well as the whole extract. Benzo(ghi)perylene showed relatively low concentrations in the SIDS extract in spite of a high...... concentration in the original dust. The PAH composition in benthic organisms (polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high concentrations in the SDS extract of road dust. When testing the toxicity of the extracted contaminants...

Adverse reactions to cosmetics and methods of testing

Directory of Open Access Journals (Sweden)

Nigam P

2009-01-01

Full Text Available Untoward reactions to cosmetics, toiletries, and topical applications are the commonest single reason for hospital referrals with allergic contact dermatitis. In most cases, these are only mild or transient and most reactions being irritant rather than allergic in nature. Various adverse effects may occur in the form of acute toxicity, percutaneous absorption, skin irritation, eye irritation, skin sensitization and photosensitization, subchronic toxicity, mutagenicity/genotoxicity, and phototoxicity/photoirritation. The safety assessment of a cosmetic product clearly depends upon how it is used, since it determines the amount of substance which may be ingested, inhaled, or absorbed through the skin or mucous membranes. Concentration of ingredients used in the different products is also important. Various test procedures include in vivo animal models and in vitro models, such as open or closed patch test, in vivo skin irritation test, skin corrosivity potential tests (rat skin transcutaneous electrical resistance test, Episkin test, eye irritation tests (in vivo eye irritancy test and Draize eye irritancy test, mutagenicity/genotoxicity tests (in vitro bacterial reverse mutation test and in vitro mammalian cell chromosome aberration test, and phototoxicity/photoirritation test (3T3 neutral red uptake phototoxicity test. Finished cosmetic products are usually tested in small populations to confirm the skin and mucous membrane compatibility, and to assess their cosmetic acceptability.

Influence of potentially confounding factors on sea urchin porewater toxicity tests

Science.gov (United States)

Carr, R.S.; Biedenbach, J.M.; Nipper, M.

2006-01-01

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. ?? 2006 Springer Science+Business Media, Inc.

Evaluating the Toxicity of the Analgesic Glutaminase Inhibitor 6-Diazo-5-Oxo-L-Norleucine in vitro and on Rat Dermal Skin Fibroblasts

Science.gov (United States)

Crosby, Heith A; Ihnat, Michael; Miller, Kenneth E

2018-01-01

6-diazo-5-oxo-l-norleucine (DON) is a glutamine antagonist produced naturally by Streptomyces. It inhibits several glutamine-dependent enzyme pathways. Of particular note is its inhibitory effect on the mitochondrial enzyme, glutaminase (GLS), the primary producer of neuronal glutamate. Glutamate is an excitatory neurotransmitter released by primary sensory peripheral nerve terminals and spinal synaptic terminals during pain signaling. Previous work using the tail incision and inflammatory models of pain has demonstrated that a single application of the glutaminase inhibitor, DON, into a surgical incision or the paw of arthritic animals results in pain relief. Even though this compound shows promise as a therapeutic agent, limited data exist regarding its dermal toxicity. As a first approach, we evaluated the effect of several concentrations of DON, on the viability, mitochondrial oxidative capacity and proliferation of rat skin fibroblasts, and then examined the effect of DON after incubation with human liver microsomes on proliferation. Finally, we evaluated DON treated rat skin (tail and hind paw) for cellular necrosis, inflammation and mitotic bodies. No significant effects (p > 0.05) of DON were noted on apoptosis, necrosis, and mitochondrial activity in experiments with cultured rat skin fibroblasts. Flow cytometry revealed the absence of apoptosis in cells treated at the IC50 of 232.5 μM. Enhanced toxicity post-exposure to human microsomes was not observed when compared to DON alone. The H&E staining of the rat skin revealed no obvious pathology in the DON treatment group (10 mM). DON has no/minimal cellular toxicity in vitro on dermal fibroblasts at concentrations that effectively provide analgesia. The local application of concentrations greater than the in vitro IC50 for DON revealed no in vivo skin toxicity. These data provide results indicating zero-to-minimal cellular toxicity with DON and support the further investigation of DON as an analgesic. PMID

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) Is Selectively Toxic to Primary Dopaminergic Neurons In Vitro

Science.gov (United States)

Griggs, Amy M.; Agim, Zeynep S.; Mishra, Vartika R.; Tambe, Mitali A.; Director-Myska, Alison E.; Turteltaub, Kenneth W.; McCabe, George P.; Rochet, Jean-Christophe; Cannon, Jason R.

2014-01-01

Parkinson's disease (PD) is the second most common neurodegenerative disease. Much data has linked the etiology of PD to a variety of environmental factors. The majority of cases are thought to arise from a combination of genetic susceptibility and environmental factors. Chronic exposures to dietary factors, including meat, have been identified as potential risk factors. Although heterocyclic amines that are produced during high-temperature meat cooking are known to be carcinogenic, their effect on the nervous system has yet to be studied in depth. In this study, we investigated neurotoxic effects of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a highly abundant heterocyclic amine in cooked meat, in vitro. We tested toxicity of PhIP and the two major phase I metabolites, N-OH-PhIP and 4′-OH-PhIP, using primary mesencephalic cultures from rat embryos. This culture system contains both dopaminergic and nondopaminergic neurons, which allows specificity of neurotoxicity to be readily examined. We find that exposure to PhIP or N-OH-PhIP is selectively toxic to dopaminergic neurons in primary cultures, resulting in a decreased percentage of dopaminergic neurons. Neurite length is decreased in surviving dopaminergic neurons. Exposure to 4′-OH-PhIP did not produce significant neurotoxicity. PhIP treatment also increased formation of oxidative damage markers, 4-hydroxy-2-nonenal (HNE) and 3-nitrotyrosine in dopaminergic neurons. Pretreatment with N-acetylcysteine was protective. Finally, treatment with blueberry extract, a dietary factor with known antioxidant and other protective mechanisms, prevented PhIP-induced toxicity. Collectively, our study suggests, for the first time, that PhIP is selectively toxic to dopaminergic neurons likely through inducing oxidative stress. PMID:24718704

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.

Toxicity assessment of organochlorine compounds detected in water environment using cultured human cell lines; Hito yurai saibo baiyokei wo mochiita suikankyo shiryochu no yuki enso kagobutsu no dokusei hyoka

Energy Technology Data Exchange (ETDEWEB)

Kunimoto, M; Yonemoto, J; Soma, Y; Nakasugi, O [National Institute for Environmental Studies, Tsukuba (Japan)

1997-11-10

As part of validation processes of in vitro toxicity assays for the risk assessment of environmental hazards, we applied an in vitro toxicity test using two human cell lines, neuroblastoma NB-1 cells and glioblastoma U-87 MG cells, to the assessment of organochlorine compounds detected in the water environment. The in vitro toxicity assay using NB-1 cells was calibrated by testing reference chemicals proposed by MEIC (Multicenter Evaluation of In Vitro Cytotoxicity), an international program for the validation of in vitro cytotoxicity assays. Beforehand, an assay using cells in frozen stock without subcultivation was examined by comparing IC50 values with the ordinary assay using subcultured cells. IC50 values for MEIC reference chemicals from the former assay showed good correlation with those from the latter assay, suggesting that the assay using cells in frozen stock can be used at least for the assessment of basal cytotoxicity. IC50 values for ten organochlorine compounds frequently detected in the sediment samples from contaminated rivers, p-chloroaniline, 3,4-dichloroaniline, p-dichlorobenzene, o-dichlorobenzene, Tris (2-chloroethyl)-phosphate, 2,5-dichlorophenol, 2,5-dichloroanisol, Triclosan and Triclocarban, were obtained with the in vitro assays and compared with their LD50 values in rats. No significant correlation, however, was seen between the IC50 and LD50 values, indicating that further improvement of in vitro toxicity assays is necessary for the application to the risk assessment of environmental hazards. 7 refs., 4 figs., 1 tab.

Toxicity Test on Malondialdehyde Content and Antioxidant Capacity of Irradiation Sterilization Rendang : In Vitro

International Nuclear Information System (INIS)

Zubaidah Irawati; Kamalita Pertiwi; Fransiska Rungkat Zakaria

2010-01-01

The safety of irradiated ethnic ready to eat food at high doses raises many questions, and recognized as one of great obstacles in the development of commercialization of food irradiation globally. People are still worried that food treated with irradiation would have induced radioactivity because free radical and its complex derivatives are formed in the irradiation process. Therefore, this study is needed to help understanding the effect of irradiated food on biological system in order to understand the possible effect to human body. The aimed of this research work was to secure the safety of irradiated food at high dose by conducting a toxicity assay using lymphocytes and erythrocytes human blood, and to determine antioxidant capacity of gamma - sterilized rendang at 45 kGy.The methods used were extraction and preparation of rending samples, culture medium preparation, lymphocytes isolation, the assays on lymphocytes proliferation, erythrocytes hemolysis,, antioxidant capacity, and malonaldehyde, respectively. The tested samples were irradiated at PATIR BATAN on 11 th November 2006 (sample A), on 14 th June 2007 (sample B), and “No Label” on 14 th June 2007 (sample C), respectively and non irradiated rending as control was also prepared. The results of proliferation assay showed that irradiated samples did neither inhibit nor induce proliferation significantly. Obviously, hemolysis rate of all samples showed increasing rate with increasing concentration or inversely correlated with dilution neither caused an increase in erythrocytes hemolysis rate nor inhibition in erythrocytes hemolysis significantly. Antioxidant capacity assay in irradiated samples showed higher value than in non-irradiated sample while irradiation treatment did not influence malonaldehyde content in rendang. (author)

Study in vitro of origin radioprotective food the radioprotective effect in vitro of food borne; Estudio in vitro de radioprotectores de origen alimentario

Energy Technology Data Exchange (ETDEWEB)

Soraino, J. M.; Sebastia, N.; Almonacid, M.; Alonso, O.; Cervera, J.; Such, E.; Silla, M. A.; Villaescusa, J. I.; Montoro, A.

2012-07-01

Study in vitro of origin radioprotective food the radioprotective effect in vitro of food borne substances studied is a first step in developing effective radioprotectors that can prevent radiation damage to healthy tissue., cannot forget that these studies must be accompanied by in vitro studies of toxicity and bioavailability to profile designing radioprotective substance.

Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC50 values of other test models

International Nuclear Information System (INIS)

Khangarot, B.S.; Das, Sangita

2009-01-01

The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC 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 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 2 ) for 17 physicochemical properties of metals or metal ions and EC 50 s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK sp ), softness parameter and some other physicochemical characteristics were significantly correlated with EC 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 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.

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

Science.gov (United States)

Belapurkar, Pranoti; Goyal, Pragya; Kar, Anand

2016-01-01

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 . 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 . 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. 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. The tested probiotic B. coagulans may have a potential role in bioremediation of Cr (VI) and Pb (II), in vivo .

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

Use of various acute, sublethal and early life-stage tests to evaluate the toxicity of refinery effluents

International Nuclear Information System (INIS)

Sherry, J.; Scott, B.; Dutka, B.

1997-01-01

The toxicities of effluents from three Ontario, Canada, refineries were assessed with microbes, plants, invertebrates, and fish. Acute toxicity was assessed by the Microtox test, an assay based on electron transport activity in submitochondrial particles, and Daphnia magna (water flea); growth of Selenastrum capricornutum (alga); growth of Lemna minor (aquatic plant); germination of Lactuca sativa (nonaquatic plant); survival, growth, and maturation of Panagrellus redivivus (nematode); and genotoxicity in the SOS-Chromotest. Only the Microtox test and the submitochondrial particle test detected acute toxicity in the effluent samples. Reduced survival and sublethal responses were caused by some effluents, but not all effluents were toxic, and none caused a response in all of the tests applied. The results suggest that the effluent treatment systems used at Ontario refineries have largely eliminated acute toxicity to the organisms in their test battery. Although reduced survival and sublethal effects were detected in some of the effluents, the effects were minor. Some of the tests provided evidence, albeit weak, of variations in the responses of the test organisms to a temporal series of effluent samples. Not unexpectedly, there were also minor differences in the responses of the tests to effluents from the three refineries. The fathead minnow test seems to be a sensitive indicator of the sublethal toxicity of Ontario refinery effluents

In-silico structure activity relationship study of toxicity endpoints by QSAR modeling (SOT)

Science.gov (United States)

Several thousand chemicals were tested in 700 toxicity-related in-vitro HTS bioassays through the EPA’s ToxCast and Tox21 projects. This chemical set only covers a portion of the chemical space of interest for environmental exposure, leading to a need to fill data gaps with alter...

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

Fourier-transform infrared spectroscopy as a novel approach to providing effect-based endpoints in duckweed toxicity testing.

Science.gov (United States)

Hu, Li-Xin; Ying, Guang-Guo; Chen, Xiao-Wen; Huang, Guo-Yong; Liu, You-Sheng; Jiang, Yu-Xia; Pan, Chang-Gui; Tian, Fei; Martin, Francis L

2017-02-01

Traditional duckweed toxicity tests only measure plant growth inhibition as an endpoint, with limited effects-based data. The present study aimed to investigate whether Fourier-transform infrared (FTIR) spectroscopy could enhance the duckweed (Lemna minor L.) toxicity test. Four chemicals (Cu, Cd, atrazine, and acetochlor) and 4 metal-containing industrial wastewater samples were tested. After exposure of duckweed to the chemicals, standard toxicity endpoints (frond number and chlorophyll content) were determined; the fronds were also interrogated using FTIR spectroscopy under optimized test conditions. Biochemical alterations associated with each treatment were assessed and further analyzed by multivariate analysis. The results showed that comparable x% of effective concentration (ECx) values could be achieved based on FTIR spectroscopy in comparison with those based on traditional toxicity endpoints. Biochemical alterations associated with different doses of toxicant were mainly attributed to lipid, protein, nucleic acid, and carbohydrate structural changes, which helped to explain toxic mechanisms. With the help of multivariate analysis, separation of clusters related to different exposure doses could be achieved. The present study is the first to show successful application of FTIR spectroscopy in standard duckweed toxicity tests with biochemical alterations as new endpoints. Environ Toxicol Chem 2017;36:346-353. © 2016 SETAC. © 2016 SETAC.

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

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...

Food safety aspect : Toxicity test of gold fish pepes sterilized by gamma irradiation in vitro

International Nuclear Information System (INIS)

Zubaidah Irawati; Kallista Rachmavika Putri; Fransiska Rungkat Zakaria

2011-01-01

Ionizing radiation is a physical preservation technique for foods using ionizing energy without impairing the products either natural characteristics or nutritive contents. Formation of free radicals and radiolytic products in irradiated foods may produce toxic substances, mutagen or carcinogenic that can affect the consumer health. Toxicity test as a part of food safety assays on gold fish (Cyprinus carpio ) pepes in a package and irradiated at the dose of 45 kGy under cryogenic condition was conducted through lymphocyte proliferation because lymphocyte cell is responsible for specific immune response and sensitive to unbalance condition between oxidant and anti oxidant in human body. Malonaldehyde content in the irradiated fish was also measured bearing in mind that malonaldehyde content could be used as indicator in the presence of free radicals and as oxidative damage indicator within the matrix of biological material. Dilution steps was done in all samples both in control and irradiated. Irradiation was conducted at three different times i.e., sample irradiated on 11 November 2006 (A), 14 June 2007(B), 5 April 2008 (C) and in 2008 (code: “no label”) (D), respectively. Proliferation of lymphocyte cell was assayed based on Stimulation Index value (SI), and free radical content of all samples was calculated based on malonaldehyde content (pmol/ml). The measurement of SI in sample without dilution showed that the highest value was found in sample B (1.356), but the lowest value was obtained in control (1.161); at one time dilution the highest value was obtained in sample D (1.344), the lowest was found in sample B (1.084) compared to control (1.259). At twice time dilution, the highest value was found in control (1.293), but the lowest was in sample D (0.984). The results of malonaldehyde content (pmol/ml) showed that sample without dilution has the highest quantity was found in sample A (0.1182 pmol/ml), but the lowest was in sample C (0.1178 pmol/ml) for

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...

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)

The utility of in vitro solubility testing in assessment of uranium exposure

International Nuclear Information System (INIS)

Eidson, A.F.; Damon, E.G.; Hahn, F.F.; Griffith, W.C. Jr.

1989-01-01

Assessment of accidental exposures in the uranium industry requires estimation of retention and excretion rates using bioassay measurements. This task is difficult if the solubility of the inhaled uranium compound is unknown. In our research, Beagle dogs were exposed to aerosols of commercial uranium milling products containing either pure ammonium diuranate (ADU) or U 3 0 8 . Dogs were exposed to ADU aerosols to achieve a median retained body burden of 0.058 mg U per kg body weight, or to U 3 0 8 aerosols to achieve a median retained body burden of 0.28 mg U per kg. A biokinetic model was applied to simulate retention and excretion of the two forms of uranium in vivo. Comparison of published in vitro dissolution data and modelling results with information from accidental human exposures showed that in vitro dissolution studies are necessary to characterise the differential solubilities of uranium compounds, and indicate the potential for kidney toxicity. Because variability in pulmonary clearance and urinary excretion rates is high among individual people, in vitro dissolution results are only marginally useful for estimating urinary excretion rates. (author)

A general mechanism for intracellular toxicity of metal-containing nanoparticles

Science.gov (United States)

Sabella, Stefania; Carney, Randy P.; Brunetti, Virgilio; Malvindi, Maria Ada; Al-Juffali, Noura; Vecchio, Giuseppe; Janes, Sam M.; Bakr, Osman M.; Cingolani, Roberto; Stellacci, Francesco; Pompa, Pier Paolo

2014-05-01

The assessment of the risks exerted by nanoparticles is a key challenge for academic, industrial, and regulatory communities worldwide. Experimental evidence points towards significant toxicity for a range of nanoparticles both in vitro and in vivo. Worldwide efforts aim at uncovering the underlying mechanisms for this toxicity. Here, we show that the intracellular ion release elicited by the acidic conditions of the lysosomal cellular compartment - where particles are abundantly internalized - is responsible for the cascading events associated with nanoparticles-induced intracellular toxicity. We call this mechanism a ``lysosome-enhanced Trojan horse effect'' since, in the case of nanoparticles, the protective cellular machinery designed to degrade foreign objects is actually responsible for their toxicity. To test our hypothesis, we compare the toxicity of similar gold particles whose main difference is in the internalization pathways. We show that particles known to pass directly through cell membranes become more toxic when modified so as to be mostly internalized by endocytosis. Furthermore, using experiments with chelating and lysosomotropic agents, we found that the toxicity mechanism for different metal containing NPs (such as metallic, metal oxide, and semiconductor NPs) is mainly associated with the release of the corresponding toxic ions. Finally, we show that particles unable to release toxic ions (such as stably coated NPs, or diamond and silica NPs) are not harmful to intracellular environments.The assessment of the risks exerted by nanoparticles is a key challenge for academic, industrial, and regulatory communities worldwide. Experimental evidence points towards significant toxicity for a range of nanoparticles both in vitro and in vivo. Worldwide efforts aim at uncovering the underlying mechanisms for this toxicity. Here, we show that the intracellular ion release elicited by the acidic conditions of the lysosomal cellular compartment - where

ToxPlorerTM: A Comprehensive Knowledgebase of Toxicity Pathways Using Ontology-driven Information Extraction

Science.gov (United States)

Realizing the potential of pathway-based toxicity testing requires a fresh look at how we describe phenomena leading to adverse effects in vivo, how we assess them in vitro and how we extrapolate them in silico across chemicals, doses and species. We developed the ToxPlorer™ fram...

Test of the acute lethal toxicity of pollutants to marine fish and invertebrates

International Nuclear Information System (INIS)

1989-01-01

This reference method describes the measurement of the acute lethal toxicity of pollutants to marine animals (fish and invertebrates) by a static (non-continuous flow) method. Procedures are given for the determination of the toxicity curve (survival time-concentration relationship) and for the estimation of median lethal concentrations (LC50). The method is suitable for use with fish and macro-invertebrate species. It is not suitable for planktonic organisms nor for determining the toxicity of oil, oil dispersants or other petroleum products. Those methods are described in Reference Methods Nos. 44 and 45, respectively. The test animals are exposed, in groups of approximately ten, to each of several concentrations of the pollutant. The animals are observed, at intervals, for several days, the test solutions being renewed regularly. A record is maintained of the survival times of individual animals exposed to each concentration of pollutant. The medial survival time of each group of animals is determined from a graphical plot of the raw data after a log-probability transformation. Median survival times and their confidence limits are plotted against concentrations of test substance to give a toxicity curve. Additionally, the same experimental data can be used to estimate the median lethal concentration (LC50) of the test substance to the animals after different periods of exposure. 3 refs, 5 figs, 3 tabs

3D in vitro technology for drug discovery.

Science.gov (United States)

Hosseinkhani, Hossein

2012-02-01

Three-dimensional (3D) in vitro systems that can mimic organ and tissue structure and function in vivo, will be of great benefit for a variety of biological applications from basic biology to toxicity testing and drug discovery. There have been several attempts to generate 3D tissue models but most of these models require costly equipment, and the most serious disadvantage in them is that they are too far from the mature human organs in vivo. Because of these problems, research and development in drug discovery, toxicity testing and biotech industries are highly expensive, and involve sacrifice of countless animals and it takes several years to bring a single drug/product to the market or to find the toxicity or otherwise of chemical entities. Our group has been actively working on several alternative models by merging biomaterials science, nanotechnology and biological principles to generate 3D in vitro living organs, to be called "Human Organs-on-Chip", to mimic natural organ/tissues, in order to reduce animal testing and clinical trials. We have fabricated a novel type of mechanically and biologically bio-mimicking collagen-based hydrogel that would provide for interconnected mini-wells in which 3D cell/organ culture of human samples in a manner similar to human organs with extracellular matrix (ECM) molecules would be possible. These products mimic the physical, chemical, and biological properties of natural organs and tissues at different scales. This paper will review the outcome of our several experiments so far in this direction and the future perspectives.

Biocompatibility of various hydoxyapatite scaffolds evaluated by proliferation of rat’s bone marrow mesenchymal stem cells: an in vitro study

Directory of Open Access Journals (Sweden)

Achmad F. Kamal

2013-12-01

Full Text Available Background: Scaffold (biomaterial biocompatibility test should be performed in vitro prior to in vivo stem cell application in animal or clinical trial. These test consists of direct and indirect toxicity test (MTT assay [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide]. Those tests were used to identify cell morphological changes, cell-substrate adhesion impairment, and reduction in cell proliferation activity.Methods: The tested scaffolds were hydroxyapatite-calcium sulphate (HA-CaSO4 (scaffold I, nano-particular HA paste (scaffold II, synthetic HA granule (scaffold III, bovine HA granule (scaffold IV, and morsellized bovine xenograft (scaffold V. Direct contact toxicity test and MTT assay [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide] were performed on those groups. In direct contact toxicity test, we put granules of various scaffolds within plates and incubated together with mesenchymal stem cells (MSCs. In MTT assay we included phenol 20 mg/mL and 100 mg/mL group as positive control. Morphology, cell adhesion impairment, and cell growth were monitored daily until day-7. Cells counting in the direct contact toxicity test was conducted on day-7.Results: There were no changes on 24 hours observation after direct contact. On day-7, an impairment of cell adhesion to plastic substrates, changes in cell morphology, and cell death were observed, especially in scaffold I, scaffold II, and scaffold V. In MTT assay, only scaffold I, phenol 20 mg/mL, and phenol 100 mg/mL showed more than 50% inhibition at 24-hour and 7-day-observation. Extracts from scaffold II, III, IV, and V did not affect the viability and proliferation of bone marrow MSCs (inhibition value < 50%. Scaffold II, III, IV and V were proven non-cytotoxic and have good biocompatibility in vitro,  no statistical significant differences were observed among the scaffold groups (p > 0.05.Conclusion: We understand which scaffold was nontoxic or the least toxic to

Polymer coated liposomes for use in the oral cavity - A study of the in vitro toxicity, effect on cell permeability and interaction with mucin

DEFF Research Database (Denmark)

Klemetsrud, Therese; Kjøniksen, Anna-Lena; Hiorth, Marianne

2018-01-01

In this study we investigated the in vitro toxicity, impact on cell permeability and mucoadhesive potential of polymer coated liposomes intended for use in the oral cavity. A TR146 cell line was used as a model. The overall aim was to end up with a selection of safe polymer coated liposomes...... with promising mucoadhesive properties for drug delivery to the oral cavity. The following polymers were tested: chitosan, low-methoxylated pectin (LM-pectin), high-methoxylated pectin (HM-pectin), amidated pectin (AM-pectin), Eudragit, poly(N-isopropylacrylamide-co-methacrylic acid) (p...... formulations promising for oromucosal administration. Although the chitosan coated liposomes affected the cell viability, this formulation also influenced the cell permeability, which makes it an interesting candidate for systemic drug delivery from the oral cavity....

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

(lethal chemical activity) was 0.047. All values were within ranges expected for baseline toxicity. Impaired swim bladder inflation was the most pronounced morphological effect and swimming activity was reduced in all exposure concentrations. Further analysis showed that the effect on swimming activity...... dilution series. We report effect values for both mortality and sublethal morphological effects based on (1) measured exposure concentrations, (2) (lipid normalized) body residues and (3) chemical activity. The LC50 for 120 hpf was 310 μg/L, CBR50 (critical body residue) was 2.72 mmol/kg fresh wt and La50...... for obtaining mechanistic toxicity information, and (3) cause no toxicity, demonstrating its potential as an extension of the FET test when testing hydrophobic chemicals....

Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment

NARCIS (Netherlands)

Chaudhari, U.; Nemade, H.; Wagh, V.; Ellis, J.K.; Srinivasan, S.; Louisse, J.

2016-01-01

The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the

Helper T cell subpopulations from women are more susceptible to the toxic effect of sodium arsenite in vitro

International Nuclear Information System (INIS)

Vega, Libia; Montes de Oca, Pavel; Saavedra, Rafael; Ostrosky-Wegman, Patricia

2004-01-01

Arsenic is known to produce inhibition as well as induction of proliferative responses in animal and human cells depending on the doses. Despite the amount of information on the immunotoxic effects of arsenic exposure in different animal models, little is known in humans. Arsenic susceptibility of lymphocyte subpopulations (T helper (Th), CD4+; T cytotoxic (Tc), CD8+) and whether arsenic effects are gender related are still to be determined. This work evaluated the in vitro toxicity of sodium arsenite on human T lymphocyte subpopulations from men and women. Peripheral blood mononuclear cells (PBMC) obtained from healthy young men and women were treated with sodium arsenite (0.01, 0.1, and 1 μM). We assessed cell viability, cell proliferation, and the proportion of Th and Tc cells after 48 or 72 h of arsenic exposure in resting and phytohemagglutinin M (PHA)-activated PBMC. We observed that sodium arsenite at 1 μM was more toxic for Th than for Tc cells in PBMC from women. Besides, T lymphocytes from women were more affected by the cell proliferation inhibition induced by arsenic, suggesting that women could be more susceptible to the toxic and immunotoxic effects caused by arsenic exposure

Health risks associated with inhaled nasal toxicants

NARCIS (Netherlands)

Feron, VJ; Arts, JHE; Kuper, CF; Slootweg, PJ; Woutersen, RA

2001-01-01

Health risks of inhaled nasal toxicants were reviewed with emphasis on chemically induced nasal lesions in humans, sensory irritation, olfactory and trigeminal nerve toxicity, nasal immunopathology and carcinogenesis, nasal responses to chemical mixtures, in vitro models, and nasal dosimetry- and

Changes in miRNA Expression Profiling during Neuronal Differentiation and Methyl Mercury-Induced Toxicity in Human in Vitro Models

Directory of Open Access Journals (Sweden)

Giorgia Pallocca

2014-08-01

Full Text Available MicroRNAs (miRNAs are implicated in the epigenetic regulation of several brain developmental processes, such as neurogenesis, neuronal differentiation, neurite outgrowth, and synaptic plasticity. The main aim of this study was to evaluate whether miRNA expression profiling could be a useful approach to detect in vitro developmental neurotoxicity. For this purpose, we assessed the changes in miRNA expression caused by methyl mercury chloride (MeHgCl, a well-known developmental neurotoxicant, comparing carcinoma pluripotent stem cells (NT-2 with human embryonic stem cells (H9, both analyzed during the early stage of neural progenitor commitment into neuronal lineage. The data indicate the activation of two distinct miRNA signatures, one activated upon neuronal differentiation and another upon MeHgCl-induced toxicity. Particularly, exposure to MeHgCl elicited, in both neural models, the down-regulation of the same six out of the ten most up-regulated neuronal pathways, as shown by the up-regulation of the corresponding miRNAs and further assessment of gene ontology (GO term and pathway enrichment analysis. Importantly, some of these common miRNA-targeted pathways defined in both cell lines are known to play a role in critical developmental processes, specific for neuronal differentiation, such as axon guidance and neurotrophin-regulated signaling. The obtained results indicate that miRNAs expression profiling could be a promising tool to assess developmental neurotoxicity pathway perturbation, contributing towards improved predictive human toxicity testing.

In vitro Alternative Methodologies for Central Nervous System Assessment: A Critique using Nanoscale Materials as an Example.

Science.gov (United States)

Identifying the potential health hazards to the central nervous system of a new family of materials presents many challenges. Whole-animal toxicity testing has been the tradition, but in vitro methods have been steadily gaining popularity. There are numerous challenges in testing...

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.

Introducing Toxics

Directory of Open Access Journals (Sweden)

David C. Bellinger

2013-04-01

Full Text Available With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present their work in as much detail as they wish. Toxics will publish original research papers, conventional reviews, meta-analyses, short communications, theoretical papers, case reports, commentaries and policy perspectives, and book reviews (Book reviews will be solicited and should not be submitted without invitation. Toxins and toxicants concern individuals from a wide range of disciplines, and Toxics is interested in receiving papers that represent the full range of approaches applied to their study, including in vitro studies, studies that use experimental animal or non-animal models, studies of humans or other biological populations, and mathematical modeling. We are excited to get underway and look forward to working with authors in the scientific and medical communities and providing them with a novel venue for sharing their work. [...

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

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...... format for testing DDB exactly at its saturation limit. Silicone O-rings were saturated by direct immersion in pure liquid DDB, which resulted in swelling of >14%. These saturated O-rings were used to establish and maintain DDB exposure exactly at the saturation limit throughout 72-h algal growth...... 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...

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.

Albizia lebbeck seed methanolic extract as a complementary therapy to manage local toxicity of Echis carinatus venom in a murine model.

Science.gov (United States)

Amog, P U; Manjuprasanna, V N; Yariswamy, M; Nanjaraj Urs, A N; Joshi, Vikram; Suvilesh, K N; Nataraju, A; Vishwanath, Bannikuppe Sannanaik; Gowda, T V

2016-11-01

Viperid venom-induced chronic local-toxicity continues even after anti-snake venom treatment. Therefore, traditional antidote Albizia lebbeck L. (Fabaceae) seed extract was tested against Echis carinatus S. (Viperidae) venom (ECV)-induced local toxicity to evaluate its complementary remedy. Soxhlet extraction of A. lebbeck seeds was performed with the increasing polarity of solvents (n-hexane to water); the extract was screened for phytochemicals (alkaloids, anthraquinones, flavonoids, glycosides, phenolics, saponins, steroids and tannins). In preliminary in vitro analysis, A. lebbeck methanolic extract (ALME) demonstrated significant inhibition of ECV proteases, the major enzyme-toxin responsible for local- toxicity. Therefore, in vitro neutralizing potential of ALME was further evaluated against hyaluronidases and phospholipase A 2 (1:1-1:100 w/w). In addition, alleviation of ECV induced characteristic local- toxicity [haemorrhage (i.d.) and myotoxicity (i.m.)] was determined in mice. ALME contained high concentrations of phenolics and flavonoids and demonstrated significant in vitro inhibition of ECV protease (IC 50  =   36.32 μg, p lebbeck in complementary medicine and identifies ALME as principle fraction responsible for antivenom properties.

Undetected Toxicity Risk in Pharmacogenetic Testing for Dihydropyrimidine Dehydrogenase

Directory of Open Access Journals (Sweden)

Felicia Stefania Falvella

2015-04-01

Full Text Available Fluoropyrimidines, the mainstay agents for the treatment of colorectal cancer, alone or as a part of combination therapies, cause severe adverse reactions in about 10%–30% of patients. Dihydropyrimidine dehydrogenase (DPD, a key enzyme in the catabolism of 5-fluorouracil, has been intensively investigated in relation to fluoropyrimidine toxicity, and several DPD gene (DPYD polymorphisms are associated with decreased enzyme activity and increased risk of fluoropyrimidine-related toxicity. In patients carrying non-functional DPYD variants (c.1905+1G>A, c.1679T>G, c.2846A>T, fluoropyrimidines should be avoided or reduced according to the patients’ homozygous or heterozygous status, respectively. For other common DPYD variants (c.496A>G, c.1129-5923C>G, c.1896T>C, conflicting data are reported and their use in clinical practice still needs to be validated. The high frequency of DPYD polymorphism and the lack of large prospective trials may explain differences in studies’ results. The epigenetic regulation of DPD expression has been recently investigated to explain the variable activity of the enzyme. DPYD promoter methylation and its regulation by microRNAs may affect the toxicity risk of fluoropyrimidines. The studies we reviewed indicate that pharmacogenetic testing is promising to direct personalised dosing of fluoropyrimidines, although further investigations are needed to establish the role of DPD in severe toxicity in patients treated for colorectal cancer.

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.

Integration of QSAR and in vitro toxicology.

Science.gov (United States)

Barratt, M D

1998-01-01

The principles of quantitative structure-activity relationships (QSAR) are based on the premise that the properties of a chemical are implicit in its molecular structure. Therefore, if a mechanistic hypothesis can be proposed linking a group of related chemicals with a particular toxic end point, the hypothesis can be used to define relevant parameters to establish a QSAR. Ways in which QSAR and in vitro toxicology can complement each other in development of alternatives to live animal experiments are described and illustrated by examples from acute toxicological end points. Integration of QSAR and in vitro methods is examined in the context of assessing mechanistic competence and improving the design of in vitro assays and the development of prediction models. The nature of biological variability is explored together with its implications for the selection of sets of chemicals for test development, optimization, and validation. Methods are described to support the use of data from in vivo tests that do not meet today's stringent requirements of acceptability. Integration of QSAR and in vitro methods into strategic approaches for the replacement, reduction, and refinement of the use of animals is described with examples. PMID:9599692

Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis.

Science.gov (United States)

Charles, Sandrine; Ducrot, Virginie; Azam, Didier; Benstead, Rachel; Brettschneider, Denise; De Schamphelaere, Karel; Filipe Goncalves, Sandra; Green, John W; Holbech, Henrik; Hutchinson, Thomas H; Faber, Daniel; Laranjeiro, Filipe; Matthiessen, Peter; Norrgren, Leif; Oehlmann, Jörg; Reategui-Zirena, Evelyn; Seeland-Fremer, Anne; Teigeler, Matthias; Thome, Jean-Pierre; Tobor Kaplon, Marysia; Weltje, Lennart; Lagadic, Laurent

2016-11-01

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 protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary 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 for the evaluation of reproductive effects of chemicals in L. stagnalis. Copyright © 2016 Elsevier Inc. All rights reserved.

Chemosensitivity and radiosensitivity testing of freshly explanted human tumour cells in vitro

International Nuclear Information System (INIS)

Wells, J.

1977-10-01

In this thesis, in vitro testing for the chemosensitivity and radiosensitivity of freshly explanted human tumour cells is described. The cells were incubated with anti-tumour drugs and either a 6-day growth test performed or a clonal growth test as a measure of survival of cell reproductive capacity. It was shown that if one aims to develop a suitable in vitro method for predicting the subsequent response of human tumour cells in situ to cytotoxic chemotherapy, the test procedure must be initiated before the explanted cells have undergone significant growth in vitro. The survival of the reproductive capacity of tumour cell explants following X-radiation was also studied. Using a 'feeder' layer technique, values for the survival curve parameter Dsub(q) were in the range 400-610 rad and the values for D 0 were in the range 120-160 rad. The shape of the X-ray survival curves did not change when cells were retested after repeated subculturing in vitro. Therefore, unlike chemosensitivity measured by the same biological end-point, radiosensitivity apparently does not change once cells have reached their maximum growth potential. (UK)

The Adverse Outcome Pathway: A conceptual framework to support toxicity testing in the 21st century

Science.gov (United States)

The field of regulatory toxicity testing is at a turning point. The U.S. National Research Council (NRC) envisioned a shift away from traditional toxicity testing and towards a focused effort to explore and understand pathways perturbed by biologically active substances or their ...

Correlation between the results of in vitro and in vivo chromosomal damage tests in consideration of exposure levels of test chemicals.

Science.gov (United States)

Yamamura, Eiji; Aruga, Chinami; Muto, Shigeharu; Baba, Nobuyuki; Uno, Yoshifumi

2018-01-01

We examined the correlation between the results of in vitro and in vivo chromosomal damage tests by using in-house data of 18 pharmaceutical candidates that showed positive results in the in vitro chromosomal aberration or micronucleus test using CHL/IU cells, and quantitatively analyzed them especially in regard to exposure levels of the compounds. Eight compounds showed that the exposure levels [maximum plasma concentration (C max ) and AUC 0-24h ] were comparable with or higher than the in vitro exposure levels [the lowest effective (positive) concentration (LEC) and AUC vitro  = LEC (μg/mL) × treatment time (h)]. Among them, 3 compounds were positive in the in vivo rodent micronucleus assays using bone marrow cells. For 2 compounds, cytotoxicity might produce false-positive results in the in vitro tests. One compound showed in vitro positive results only in the condition with S9 mix which indicated sufficient concentration of unidentified active metabolite(s) might not reach the bone marrow to induce micronuclei. These facts suggested that the in vivo exposure levels being equal to or higher than the in vitro exposure levels might be an important factor to detect in vivo chromosomal damage induced by test chemicals.

Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

International Nuclear Information System (INIS)

Hoess, S.; Ahlf, W.; Fahnenstich, C.; Gilberg, D.; Hollert, H.; Melbye, K.; Meller, M.; Hammers-Wirtz, M.; Heininger, P.; Neumann-Hensel, H.; Ottermanns, R.; Ratte, H.-T.

2010-01-01

Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

Energy Technology Data Exchange (ETDEWEB)

Hoess, S., E-mail: hoess@ecossa.d [Ecossa, Giselastr. 6, 82319 Starnberg (Germany); Institute of Biodiversity - Network (IBN), Dreikronengasse 2, 93047 Regensburg (Germany); Ahlf, W., E-mail: ahlf@tu-harburg.d [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Fahnenstich, C. [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Gilberg, D., E-mail: d-gilberg@ect.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hollert, H., E-mail: henner.hollert@bio5.rwth-aachen.d [Department of Ecosystem Analysis, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Melbye, K. [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Meller, M., E-mail: m-meller@ecotox-consult.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hammers-Wirtz, M., E-mail: hammers-wirtz@gaiac.rwth-aachen.d [Research Institute for Ecosystem Analysis and Assessment (gaiac), RWTH Aachen University, Worringerweg 1, 52056 Aachen (Germany); Heininger, P., E-mail: heininger@bafg.d [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56070 Koblenz (Germany); Neumann-Hensel, H., E-mail: hensel@fintelmann-meyer.d [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Ottermanns, R., E-mail: ottermanns@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Ratte, H.-T., E-mail: toni.ratte@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

2010-09-15

Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

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.

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.

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.

Design and Analysis of Chronic Aquatic Tests of Toxicity with Daphnia magna.

Science.gov (United States)

1981-12-01

surface waters. From that need evolved numerous standard toxicity tests. Aquatic toxicologists and biologists developed, refine,, and standard- ized many...experimental categorization summary sheets prepared by Dr. William van der Schalie, which is shown in Table I.I. 7 j-. " .’?, i...partial solution to this dilema can be obtained by studying the effects of the solvent alone. If the solvent by itself produces no toxic responses at

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.

Refinery water (intake and effluent) quality: Update of 1970s with 1990s toxicity testing

International Nuclear Information System (INIS)

Chapman, P.M.; Paine, M.D.; Moran, T.; Kierstead, T.

1994-01-01

The quality of two separate refinery intake waters and effluents was investigated: Petro-Canada (Oakville) and Novacor (Corunna Operations). This study comprised eight different test organized and 22 different toxicity end points, was built on and complemented pioneering 1970s work at the Petro-Canada refinery, and was designed to (a) determine any changes in effluent quality, (b) determine any previously unsuspected effluent toxicity, and (c) determine any potential for chronic toxicity in the effluent. Although Petro-Canada has steadily reduced contaminants in its effluent since the earlier study, toxicity has not changed and no new toxic effects were identified. Effect thresholds for the most sensitive animal species (Daphnia pulex) were 1 to 10% effluent in both studies. The Novacor effluent had lesser effects on biota than the Petro-Canada effluent. Intake waters demonstrated toxicity in some tests. Chronic effects on invertebrates and fish in receiving waters are predicted not to occur in the Novacor effluent is diluted 10- to 20-fold and the Petro-Canada effluent is diluted 50- to 100-fold

21 CFR 312.160 - Drugs for investigational use in laboratory research animals or in vitro tests.

Science.gov (United States)

2010-04-01

... research animals or in vitro tests. 312.160 Section 312.160 Food and Drugs FOOD AND DRUG ADMINISTRATION... Drugs for Investigational Use in Laboratory Research Animals or In Vitro Tests § 312.160 Drugs for investigational use in laboratory research animals or in vitro tests. (a) Authorization to ship. (1)(i) A person...

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

2012-12-01

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 Cd2+ ions and indeed we show that there is leaching of Cd2+ 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.

Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0)

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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...

Sensitivity of screening-level toxicity tests using soils from a former petroleum refinery

International Nuclear Information System (INIS)

Pauwels, S.; Bureau, J.; Roy, Y.; Allen, B.; Robidoux, P.Y.; Soucy, M.

1995-01-01

The authors tested five composite soil samples from a former refinery. The samples included a reference soil (Mineral Oil and Grease, MO and G < 40 ppm), thermally-treated soil, biotreated soil, and two untreated soils. They evaluated toxicity using the earthworm E. foetida, lettuce, cress, barley, Microtox, green algae, fathead minnow, and D. magna. The endpoints measured were lethality, seed germination, root elongation, growth, and bioluminescence. Toxicity, as measured by the number of positive responses, increased as follows: biotreated soil < untreated soil No. 1 < reference soil < thermally-treated soil and untreated soil No. 2. The biotreated soil generated only one positive response, whereas the thermally-treated soil and untreated soil No. 2 generated five positive responses. The most sensitive and discriminant terrestrial endpoint was lettuce root elongation which responded to untreated soil No. 1, thermally-treated soil, and reference soil. The least sensitive was barley seed germination for which no toxicity was detected. The most sensitive and discriminant aquatic endpoint was green algae growth which responded to untreated soil No. 1, thermally-treated soil, and reference soil. The least sensitive was D. magna for which no toxicity was detected. Overall, soil and aqueous extract toxicity was spotty and no consistent patterns emerged to differentiate the five soils. Biotreatment significantly reduced the effects of the contamination. Aqueous toxicity was measured in the reference soil, probably because of the presence of unknown dissolved compounds in the aqueous extract. Finally, clear differences in sensitivity existed among the test species

In vitro and in vivo trypanocidal activity of flavonoids from Delphinium staphisagria against Chagas disease.

Science.gov (United States)

Marín, Clotilde; Ramírez-Macías, Inmaculada; López-Céspedes, Angeles; Olmo, Francisco; Villegas, Noelia; Díaz, Jesús G; Rosales, María José; Gutiérrez-Sánchez, Ramón; Sánchez-Moreno, Manuel

2011-04-25

The in vitro and in vivo trypanocidal activities of nine flavonoids (1-9) isolated from the aerial parts of Delphinium staphisagria have been studied in both the acute and chronic phases of Chagas disease. The antiproliferative activity of these substances against Trypanosoma cruzi (epimastigote, amastigote, and trypomastigote forms) in some cases exhibited more potent antitrypanosomatid activity and lower toxicity than the reference drug, benznidazole. Studies in vitro using ultrastructural analysis together with metabolism-excretion studies were also performed in order to identify the possible action mechanism of the compounds tested. Alterations mainly at the level of the mitochondria may explain metabolic changes in succinate and acetate production, perhaps due to the disturbance of the enzymes involved in sugar metabolism within the mitochondrion. In vivo studies provided results consistent with those observed in vitro. No signs of toxicity were detected in mice treated with the flavonoids tested, and the parasitic charge was significantly lower than in the control assay with benznidazole. The effects of these compounds were also demonstrated with the change in the anti-T. cruzi antibody levels during the chronic stage.

Evaluating the Zebrafish Embryo Toxicity Test for Pesticide Hazard Screening

Science.gov (United States)

Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more reso...

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.

Predicting Developmental Toxicity of ToxCast Phase I Chemicals Using Human Embryonic Stem Cells and Metabolomics

Science.gov (United States)

EPA’s ToxRefDB contains prenatal guideline study data from rats and rabbits for over 240 chemicals that overlap with the ToxCast in vitro high throughput screening project. A subset of these compounds were tested in Stemina Biomarker Discovery's developmental toxicity platform, a...

Metabolic enzyme microarray coupled with miniaturized cell-culture array technology for high-throughput toxicity screening.

Science.gov (United States)

Lee, Moo-Yeal; Dordick, Jonathan S; Clark, Douglas S

2010-01-01

Due to poor drug candidate safety profiles that are often identified late in the drug development process, the clinical progression of new chemical entities to pharmaceuticals remains hindered, thus resulting in the high cost of drug discovery. To accelerate the identification of safer drug candidates and improve the clinical progression of drug candidates to pharmaceuticals, it is important to develop high-throughput tools that can provide early-stage predictive toxicology data. In particular, in vitro cell-based systems that can accurately mimic the human in vivo response and predict the impact of drug candidates on human toxicology are needed to accelerate the assessment of drug candidate toxicity and human metabolism earlier in the drug development process. The in vitro techniques that provide a high degree of human toxicity prediction will be perhaps more important in cosmetic and chemical industries in Europe, as animal toxicity testing is being phased out entirely in the immediate future.We have developed a metabolic enzyme microarray (the Metabolizing Enzyme Toxicology Assay Chip, or MetaChip) and a miniaturized three-dimensional (3D) cell-culture array (the Data Analysis Toxicology Assay Chip, or DataChip) for high-throughput toxicity screening of target compounds and their metabolic enzyme-generated products. The human or rat MetaChip contains an array of encapsulated metabolic enzymes that is designed to emulate the metabolic reactions in the human or rat liver. The human or rat DataChip contains an array of 3D human or rat cells encapsulated in alginate gels for cell-based toxicity screening. By combining the DataChip with the complementary MetaChip, in vitro toxicity results are obtained that correlate well with in vivo rat data.

An empirical comparison of effective concentration estimators for evaluating aquatic toxicity test responses

Energy Technology Data Exchange (ETDEWEB)

Bailer, A.J.; Hughes, M.R.; Denton, D.L.; Oris, J.T.

2000-01-01

Aquatic toxicity tests are statistically evaluated by either hypothesis testing procedures to derive a no-observed-effect concentration or by inverting regression models to calculate the concentration associated with a specific reduction from the control response. These latter methods can be described as potency estimation methods. Standard US Environmental Protection Agency (USEPA) potency estimation methods are based on two different techniques. For continuous or count response data, a nominally nonparametric method that assumes monotonic decreasing responses and piecewise linear patterns between successive concentration groups is used. For quantal responses, a probit regression model with a linear dose term is fit. These techniques were compared with a recently developed parametric regression-based estimator, the relative inhibition estimator, RIp. This method is based on fitting generalized linear models, followed by estimation of the concentration associated with a particular decrement relative to control responses. These estimators, with levels of inhibition (p) of 25 and 50%, were applied to a series of chronic toxicity tests in a US EPA region 9 database of reference toxicity tests. Biological responses evaluated in these toxicity tests included the number of young produced in three broods by the water flea (Ceriodaphnia dubia) and germination success and tube length data from the giant kelp (Macrocystis pyrifera). The greatest discrepancy between the RIp and standard US EPA estimators was observed for C. dubia. The concentration-response pattern for this biological endpoint exhibited nonmonotonicity more frequently than for any of the other endpoint. Future work should consider optimal experimental designs to estimate these quantities, methods for constructing confidence intervals, and simulation studies to explore the behavior of these estimators under known conditions.

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.

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

2017-10-01

This study investigates the scolicidal effects of Cinnamomum zeylanicum essential oil against the protoscoleces of hydatid cysts and its toxicity in the mice model. 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). 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 LD 50 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. The results exhibited the favorable scolicidal activity of C. zeylanicum , which could be applied as a natural scolicidal agent in hydatid cyst surgery. 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; LD50: Lethal dose 50%; I.p: Intraperitoneally.

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

The Effects of Piroxicam in the Attenuation of MPP+/MPTP Toxicity In Vitro and In Vivo

Science.gov (United States)

Soliman, Y.; Jackson, T.; Mazzio, E.

2010-01-01

Several lines of evidence support the neuroprotective action of cyclooxygenase-2 (COX-2) inhibitors in various models of Parkinson's disease (PD). In the current study, we investigated the neuroprotective properties of several COX inhibitors against 1-methyl-4-phenylpyridinium (MPP+) in neuroblastoma Neuro 2A (N-2A) cells in vitro and the protection against degeneration of substantia nigra pars compacta (SNc) dopaminergic (DA) neurons after the administration of 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine (MPTP) in C57/BL6 male mice. The data obtained demonstrate a lack of protective effects observed by COX 1-2 inhibitors ibuprofen and acetylsalicylic acid against MPP+ toxicity in N-2A, where piroxicam was protective in a dose dependent manner (MPP+ control: 15 ± 2% MPP+ piroxicam: 5 mM 89 ± 4%). The data also indicate a drop in mitochondrial oxygen (O2) consumption and ATP during MPP+ toxicity with no restoration of mitochondrial function concurrent to a heightened concentration of somatic ATP during piroxicam rescue. These findings indicate that the neuroprotective effects of COX inhibitors against MPP+ are not consistent, but that piroxicam may work through an unique mechanism to propel anaerobic energy metabolism. On the other hand, using mice, piroxicam (20 mg/kg) was effective against MPTP-induced dopaminergic degeneration in the (SNc) and loss of locomotive function in mice. Administering a 3 day pre-treatment of piroxicam (20 mg/kg) was effective in antagonizing the losses in SNc tyrosine hydroxylase protein expression, SNc DA concentration and associated anomaly in ambulatory locomotor activity. It was concluded from these findings that piroxicam is unique among COX inhibitors in providing very significant neuroprotection against MPP+ in vitro and in vivo. PMID:18612814

An assessment of whole effluent toxicity testing as a means of regulating waters produced by the oil and gas industry

International Nuclear Information System (INIS)

Hill, S.L.; Bergman, H.L.

1993-01-01

Approximately 500 million barrels of produced water are discharged to Wyoming's surface waters by the oil and gas industry. This discharges are of two types: direct and indirect. The direct discharges have been issued NPDES permits requiring whole effluent toxicity testing. Toxicity testing requirements have not been incorporated into permits written for indirect discharges because of the applicability of toxicity testing for regulating these waters has not been determined. Preliminary testing has shown that most produced waters are toxic at the point of discharge because of high concentrations of hydrogen sulfide, but that the toxicity of an indirect discharge is often lost before it reaches a receiving stream. Thus, whole effluent toxicity testing of an indirect discharge may be overly stringent, resulting in treatment or reinjection of the water or closure of the well. Any of these options would have severe economic consequences for oil producers and the state's agricultural industry. The purpose of this study was to determine whether whole effluent toxicity testing actually predicts the in-stream effects of indirect discharges on water quality and benthic invertebrate populations. The authors will report the results of short-term ambient toxicity tests and in-stream bioassessments performed upstream and downstream of six indirect discharges located in four drainages in Wyoming

Rocuronium is more hepatotoxic than succinylcholine in vitro.

Science.gov (United States)

Sauer, Martin; Piel, Ines; Haubner, Cristof; Richter, Georg; Mann, Miriam; Nöldge-Schomburg, Gabriele; Mencke, Thomas

2017-09-01

The development of liver failure is a major problem in critically ill patients. The hepatotoxicity of many drugs, as one important reason for liver failure, is poorly screened for in human models. Rocuronium and succinylcholine are neuromuscular blocking agents used for tracheal intubation and for rapid-sequence induction. We used an in-vitro test with a permanent cell line and compared rocuronium and succinylcholine for hepatotoxicity. In-vitro study. A basic science laboratory, University Hospital Rostock, Germany. The basic test compound is the permanent human liver cell line HepG2/C3A. In a standardised microtitre plate assay the toxicity of different concentrations of rocuronium, succinylcholine and plasma control was tested. After two incubation periods of 3 days, the viability of cells (XTT test, lactate dehydrogenase release and trypan blue staining), micro-albumin synthesis and the cytochrome 1A2 activity (metabolism of ethoxyresorufin) were measured. Differences between rocuronium and succinylcholine were assessed using the Kruskal-Wallis one-way test and two-tailed Mann-Whitney U test. Rocuronium, but not succinylcholine, led to a significant dose-dependent decrease of viability, albumin synthesis and cytochrome 1A2 activity of test cells. An in-vitro test with a cell line showed hepatotoxicity of rocuronium that was dose-dependent. Further studies are needed to investigate the underlying mechanisms of the effects of rocuronium on hepatic cellular integrity. Not suitable.

Consensus report on the future of animal-free systemic toxicity testing

OpenAIRE

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

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 Cen...

A roadmap for the development of alternative (non-animal) methods for systemic toxicity testing - t4 report*.

Science.gov (United States)

Basketter, David A; Clewell, Harvey; Kimber, Ian; Rossi, Annamaria; Blaauboer, Bas; Burrier, Robert; Daneshian, Mardas; Eskes, Chantra; Goldberg, Alan; Hasiwa, Nina; Hoffmann, Sebastian; Jaworska, Joanna; Knudsen, Thomas B; Landsiedel, Robert; Leist, Marcel; Locke, Paul; Maxwell, Gavin; McKim, James; McVey, Emily A; Ouédraogo, Gladys; Patlewicz, Grace; Pelkonen, Olavi; Roggen, Erwin; Rovida, Costanza; Ruhdel, Irmela; Schwarz, Michael; Schepky, Andreas; Schoeters, Greet; Skinner, Nigel; Trentz, Kerstin; Turner, Marian; Vanparys, Philippe; Yager, James; Zurlo, Joanne; Hartung, Thomas

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 especially true in the context of the scheduled 2013 marketing ban on cosmetic ingredients tested for systemic toxicity. Based on a major analysis of the status of alternative methods (Adler et al., 2011) and its independent review (Hartung et al., 2011), the present report proposes a roadmap for how to overcome the acknowledged scientific gaps for the full replacement of systemic toxicity testing using animals. Five whitepapers were commissioned addressing toxicokinetics, skin sensitization, repeated-dose toxicity, carcinogenicity, and reproductive toxicity testing. An expert workshop of 35 participants from Europe and the US discussed and refined these whitepapers, which were subsequently compiled to form the present report. By prioritizing the many options to move the field forward, the expert group hopes to advance regulatory science.

Probabilistic risk assessment of gold nanoparticles after intravenous administration by integrating in vitro and in vivo toxicity with physiologically based pharmacokinetic modeling.

Science.gov (United States)

Cheng, Yi-Hsien; Riviere, Jim E; Monteiro-Riviere, Nancy A; Lin, Zhoumeng

2018-04-14

This study aimed to conduct an integrated and probabilistic risk assessment of gold nanoparticles (AuNPs) based on recently published in vitro and in vivo toxicity studies coupled to a physiologically based pharmacokinetic (PBPK) model. Dose-response relationships were characterized based on cell viability assays in various human cell types. A previously well-validated human PBPK model for AuNPs was applied to quantify internal concentrations in liver, kidney, skin, and venous plasma. By applying a Bayesian-based probabilistic risk assessment approach incorporating Monte Carlo simulation, probable human cell death fractions were characterized. Additionally, we implemented in vitro to in vivo and animal-to-human extrapolation approaches to independently estimate external exposure levels of AuNPs that cause minimal toxicity. Our results suggest that under the highest dosing level employed in existing animal studies (worst-case scenario), AuNPs coated with branched polyethylenimine (BPEI) would likely induce ∼90-100% cellular death, implying high cytotoxicity compared to risk prediction, and point of departure estimation of AuNP exposure for humans and illustrate an approach that could be applied to other NPs when sufficient data are available.

Acute toxicity tests using rotifers. 4. Effects of cyst age, temperature, and salinity on the sensitivity of Brachionus calyciflorus

Energy Technology Data Exchange (ETDEWEB)

Snell, T.W.; Moffat, B.D.; Janssen, C.; Persoone, G. (University of Tampa, Florida (USA))

1991-06-01

Several aspects of the response to toxicants using a standardized toxicity test with the freshwater rotifer Brachionus calyciflorus are described. Test animals are obtained by hatching cysts which produce animals of similar age and physiological condition. The acute toxicity of 28 compounds is described with 24-hr LC50's. The LC50's span five orders of magnitude, from silver at 0.008 mg.liter-1 to benzene at more than 1000 mg.liter-1. Control mortality in 84 tests averaged 2% with a standard deviation of 3%, indicating very consistent test sensitivity. Only once in 84 trials did a test fail because of excessive control mortality, yielding a failure rate of 1.2%. Cyst age from 0 to 18 months had no effect on the sensitivity of neonates to reference toxicants. Both high and low temperatures increased rotifer sensitivity to reference toxicants. Copper sensitivity was greater at 10, 25, and 30 degrees C compared with results at 20 degrees C. Likewise, sodium pentachlorophenol toxicity was greater at 10 and 30 degrees C compared with results at 20 degrees C. Survivorship curves at 25 degrees C of neonates under control conditions indicated that mortality begins at about 30 hr. This places a practical limit on toxicant exposure for the assay of 24 hr. B. calyciflorus cysts hatch at salinities up to 5 ppt and acute toxicity tests using pentachlorophenol at this salinity yielded LC50's about one-half those of standard freshwater. B. calyciflorus is preferred over Brachionus plicatilis for toxicity tests in salinities up to 5 ppt because it is consistently more sensitive.

Assessing contaminant sensitivity of endangered and threatened aquatic species: Part III. Effluent toxicity tests

Science.gov (United States)

Dwyer, F.J.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Whites, D.W.; Augspurger, T.; Canfield, T.J.; Mount, D.R.; Mayer, F.L.

2005-01-01

Toxicity tests using standard effluent test procedures described by the U.S. Environmental Protection Agency were conducted with Ceriodaphnia dubia, fathead minnows (Pimephales promelas), and seven threatened and endangered (listed) fish species from four families: (1) Acipenseridae: shortnose sturgeon (Acipenser brevirostrum); (2) Catostomidae; razorback sucker (Xyrauchen texanus); (3) Cyprinidae: bonytail chub (Gila elegans), Cape Fear shiner (Notropis mekistocholas) Colorado pikeminnow (Ptychocheilus lucius), and spotfin chub (Cyprinella monacha); and (4) Poecillidae: Gila topminnow (Poeciliopsis occidentalis). We conducted 7-day survival and growth studies with embryo-larval fathead minnows and analogous exposures using the listed species. Survival and reproduction were also determined with C. dubia. Tests were conducted with carbaryl, ammonia-or a simulated effluent complex mixture of carbaryl, copper, 4-nonylphenol, pentachlorophenol and permethrin at equitoxic proportions. In addition, Cape Fear shiners and spotfin chub were tested using diazinon, copper, and chlorine. Toxicity tests were also conducted with field-collected effluents from domestic or industrial facilities. Bonytail chub and razorback suckers were tested with effluents collected in Arizona whereas effluent samples collected from North Carolina were tested with Cape Fear shiner, spotfin chub, and shortnose sturgeon. The fathead minnow 7-day effluent test was often a reliable estimator of toxic effects to the listed fishes. However, in 21 % of the tests, a listed species was more sensitive than fathead minnows. More sensitive species results varied by test so that usually no species was always more or less sensitive than fathead minnows. Only the Gila topminnow was consistently less sensitive than the fathead minnow. Listed fish species were protected 96% of the time when results for both fathead minnows and C. dubia were considered, thus reinforcing the value of standard whole

Expert consensus on an in vitro approach to assess pulmonary fibrogenic potential of aerosolized nanomaterials.

Science.gov (United States)

Clippinger, Amy J; Ahluwalia, Arti; Allen, David; Bonner, James C; Casey, Warren; Castranova, Vincent; David, Raymond M; Halappanavar, Sabina; Hotchkiss, Jon A; Jarabek, Annie M; Maier, Monika; Polk, William; Rothen-Rutishauser, Barbara; Sayes, Christie M; Sayre, Phil; Sharma, Monita; Stone, Vicki

2016-07-01

The increasing use of multi-walled carbon nanotubes (MWCNTs) in consumer products and their potential to induce adverse lung effects following inhalation has lead to much interest in better understanding the hazard associated with these nanomaterials (NMs). While the current regulatory requirement for substances of concern, such as MWCNTs, in many jurisdictions is a 90-day rodent inhalation test, the monetary, ethical, and scientific concerns associated with this test led an international expert group to convene in Washington, DC, USA, to discuss alternative approaches to evaluate the inhalation toxicity of MWCNTs. Pulmonary fibrosis was identified as a key adverse outcome linked to MWCNT exposure, and recommendations were made on the design of an in vitro assay that is predictive of the fibrotic potential of MWCNTs. While fibrosis takes weeks or months to develop in vivo, an in vitro test system may more rapidly predict fibrogenic potential by monitoring pro-fibrotic mediators (e.g., cytokines and growth factors). Therefore, the workshop discussions focused on the necessary specifications related to the development and evaluation of such an in vitro system. Recommendations were made for designing a system using lung-relevant cells co-cultured at the air-liquid interface to assess the pro-fibrogenic potential of aerosolized MWCNTs, while considering human-relevant dosimetry and NM life cycle transformations. The workshop discussions provided the fundamental design components of an air-liquid interface in vitro test system that will be subsequently expanded to the development of an alternative testing strategy to predict pulmonary toxicity and to generate data that will enable effective risk assessment of NMs.

Quick, portable toxicity testing of marine or terrigenous fluids, sediments, or chemicals with bioluminescent organism

International Nuclear Information System (INIS)

Sabate, R.W.; Stiffey, A.V.; Dewailly, E.L.

1995-01-01

A hand-held, battery-operated instrument, which measures bioluminescence inhibition of the microscopic marine dinoflagellate Pyrocystis lunula, is capable of field-testing substances for toxicity. The organism is sensitive to ppb of strong toxicants. It tolerates some solvents in concentrations necessary for testing lipophylic samples. A test consumes only micrograms of sample. This method requires no adjustments for salinity, pH, color, or turbidity. It has been used successfully to test oil-well drilling fluids, brines produced with oil, waters and sediments from streams and lakes and petroleum-plant effluents containing contaminants such as benzene. The test is non-specific; however, if the substance is known, the end-point effects a direct measurement of its concentration. One-hour toxicity screening tests in the field produce results comparable to the standard four-hour laboratory test. Keeping the sample in the dark during incubation and testing, together with shortness of the overall procedure, eliminates anomalies from light-sensitive substances. Day-to-day variation, as well as among test replicates, is less than 10%. This quick method yields results comparable with a quick test that uses Photobacterium phosphoria, and with 96-hour tests that use Mysidopsis bahia, Artemia salina, Gonyaulax polyedra, Pimephales promelas, Ceriodaphnia dubia, and Cyprinodon variegatus

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...... protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary...

Test systems in drug discovery for hazard identification and risk assessment of human drug-induced liver injury.

Science.gov (United States)

Weaver, Richard J; Betts, Catherine; Blomme, Eric A G; Gerets, Helga H J; Gjervig Jensen, Klaus; Hewitt, Philip G; Juhila, Satu; Labbe, Gilles; Liguori, Michael J; Mesens, Natalie; Ogese, Monday O; Persson, Mikael; Snoeys, Jan; Stevens, James L; Walker, Tracy; Park, B Kevin

2017-07-01

The liver is an important target for drug-induced toxicities. Early detection of hepatotoxic drugs requires use of well-characterized test systems, yet current knowledge, gaps and limitations of tests employed remains an important issue for drug development. Areas Covered: The current state of the science, understanding and application of test systems in use for the detection of drug-induced cytotoxicity, mitochondrial toxicity, cholestasis and inflammation is summarized. The test systems highlighted herein cover mostly in vitro and some in vivo models and endpoint measurements used in the assessment of small molecule toxic liabilities. Opportunities for research efforts in areas necessitating the development of specific tests and improved mechanistic understanding are highlighted. Expert Opinion: Use of in vitro test systems for safety optimization will remain a core activity in drug discovery. Substantial inroads have been made with a number of assays established for human Drug-induced Liver Injury. There nevertheless remain significant gaps with a need for improved in vitro tools and novel tests to address specific mechanisms of human Drug-Induced Liver Injury. Progress in these areas will necessitate not only models fit for application, but also mechanistic understanding of how chemical insult on the liver occurs in order to identify translational and quantifiable readouts for decision-making.

Integrating the fish embryo toxicity test as triad element for sediment toxicity assessment based on the water framework directive approach

Energy Technology Data Exchange (ETDEWEB)

Bartzke, Mariana [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Dept. Bioanalytical Ecotoxicology, Helmholtz Centre for Environmental Research, UFZ, Leipzig (Germany); Delov, Vera [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Ecotoxicology, Fraunhofer Inst. for Molecular Biology and Applied Ecology IME, Aachen (Germany); Stahlschmidt-Allner, Petra; Allner, Bernhard [Gobio GmbH, Aarbergen/Kettenbach (Germany); Oehlmann, Joerg [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany)

2010-04-15

Purpose: The objective of this study was to complement analyses according to the European Union Water Framework Directive (WFD) with a sediment toxicity analysis as part of an integrated river assessment. To this end, Hessian water courses were analyzed using the sediment quality triad concept according to Chapman with chemical analyses, in situ effect evaluations, and ecotoxicological assessments. For the ecotoxicological assessment (fish embryo toxicity test with Danio rerio), a new evaluation scheme was developed, the fish teratogenicity index (FTI), that allows for a classification of sediments into ecological quality classes compliant to the WFD. Materials and methods sediment and macrozoobenthos samples were taken from tributaries of the rivers Fulda and Lahn. Sediments were characterized regarding particle size, carbon, heavy metals, and polyaromatic hydrocarbon content. Macroinvertebrate samples were taken via multi-habitat sampling. The fish embryo toxicity test with D. rerio was conducted as a contact assay on the basis of DIN 38415-6. Results and discussion The integrated assessment indicated a significant influence of heavy metals and carbon content on macroinvertebrate communities. The bioaccessibility of sediment pollutants were clearly demonstrated by the FTI, which showed a wide range of adverse effects. A significant linear relationship between metals and the FTI was detected. However, there was no statistically significant evidence that macroinvertebrate communities were affected by the hydromorphological quality clements at the sampling sites. Conclusions The new scheme for the assessment of fish embryo toxicity test was successfully applied. The results suggest that sediment compounds impact macroinvertebrate communities and early development of fish. It demonstrates that the quality of sediments should be evaluated on a routine basis as part of an integrated river assessment. (orig.)

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.

Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors.

Science.gov (United States)

Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene

2015-07-01

The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests. © 2015 SETAC.

In vitro and in vivo antitrypanosomal activity of Xanthium strumarium leaves.

Science.gov (United States)

Talakal, T S; Dwivedi, S K; Sharma, S R

1995-12-15

Antitrypanosomal activity of crude 50% ethanolic extract of Xanthium strumarium leaves was studied in vitro and in vivo. The extract exhibited trypanocidal activity at all four concentrations tested i.e. 5, 50, 500 and 1000 micrograms/ml, in vitro. In vivo trial revealed that the extract exerted antitrypanosomal effect at dosage of 100, 300 and 1000 mg/kg, intraperitoneally. At 100 and 300 mg/kg doses the survival period of the Trypanosoma evansi infected mice was significantly prolonged. However, the extract was found to be toxic to the animals at 1000 mg/kg dose.

Toxicity of ozone and nitrogen dioxide to alveolar macrophages: comparative study revealing differences in their mechanism of toxic action

NARCIS (Netherlands)

Rietjens, I. M.; Poelen, M. C.; Hempenius, R. A.; Gijbels, M. J.; Alink, G. M.

1986-01-01

The toxicity of ozone and nitrogen dioxide is generally ascribed to their oxidative potential. In this study their toxic mechanism of action was compared using an intact cell model. Rat alveolar macrophages were exposed by means of gas diffusion through a Teflon film. In this in vitro system, ozone

Sex in a test tube: testing the benefits of in vitro recombination.

Science.gov (United States)

Pesce, Diego; Lehman, Niles; de Visser, J Arjan G M

2016-10-19

The origin and evolution of sex, and the associated role of recombination, present a major problem in biology. Sex typically involves recombination of closely related DNA or RNA sequences, which is fundamentally a random process that creates but also breaks up beneficial allele combinations. Directed evolution experiments, which combine in vitro mutation and recombination protocols with in vitro or in vivo selection, have proved to be an effective approach for improving functionality of nucleic acids and enzymes. As this approach allows extreme control over evolutionary conditions and parameters, it also facilitates the detection of small or position-specific recombination benefits and benefits associated with recombination between highly divergent genotypes. Yet, in vitro approaches have been largely exploratory and motivated by obtaining improved end products rather than testing hypotheses of recombination benefits. Here, we review the various experimental systems and approaches used by in vitro studies of recombination, discuss what they say about the evolutionary role of recombination, and sketch their potential for addressing extant questions about the evolutionary role of sex and recombination, in particular on complex fitness landscapes. We also review recent insights into the role of 'extracellular recombination' during the origin of life.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. © 2016 The Author(s).

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.

Cellular toxicity of calf blood extract on human corneal epithelial cells in vitro.

Science.gov (United States)

Park, Young Min; Kim, Su Jin; Han, Young Sang; Lee, Jong Soo

2015-01-01

To investigate the biologic effects of the calf blood extract on corneal epithelial cells in vitro. The effects on corneal epithelial cells were evaluated after 1, 4, 12, and 24 h of exposure to various concentrations of calf blood extract (3, 5, 8 and 16%). The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was performed to measure levels of cellular metabolic activity. The lactate dehydrogenase (LDH) assay was performed to determine the extent of cellular damage. Cellular morphology was examined using phase-contrast microscopy. The scratch wound assay was performed to quantify the migration of corneal epithelial cells. At the 3 and 5% concentrations of calf blood extract, MTT values were similar to those observed in the control group. However, at a concentration of 8 and 16%, cellular metabolic activity was significantly decreased after 4 h of exposure to calf blood extract. After 12 h of exposure to 8 and 16% concentrations of calf blood extract, LDH activity and cellular morphological damage to the corneal epithelial cells were significantly increased. There was no evidence of cellular migration after 12 h exposure to 5% or higher concentration of calf blood extract because of cellular toxicity. Compared with normal corneal epithelial cells, the cellular activity was decreased, and toxicity was increased after over 12 h of exposure to more than 5% concentration of calf blood extract. Further clinical studies will be necessary to determine the optimal concentration and exposure time for the topical application of eye drops containing calf blood extract.

Testing of toxicity based methods to develop site specific clean up objectives - phase 1: Toxicity protocol screening and applicability

International Nuclear Information System (INIS)

Hamilton, H.; Kerr, D.; Thorne, W.; Taylor, B.; Zadnik, M.; Goudey, S.; Birkholz, D.

1994-03-01

A study was conducted to develop a cost-effective and practical protocol for using bio-assay based toxicity assessment methods for remediation of decommissioned oil and gas production, and processing facilities. The objective was to generate site-specific remediation criteria for contaminated sites. Most companies have used the chemical-specific approach which, however, did not meet the ultimate land use goal of agricultural production. The toxicity assessment method described in this study dealt with potential impairment to agricultural crop production and natural ecosystems. Human health concerns were not specifically addressed. It was suggested that chemical-specific methods should be used when human health concerns exist. . Results showed that toxicity tests will more directly identify ecological stress caused by site contamination than chemical-specific remediation criteria, which can be unnecessarily protective. 11 refs., 7 tabs., 6 figs

Developmental toxicity of thyroid-active compounds in a zebrafish embryotoxicity test

NARCIS (Netherlands)

Jomaa, B.; Hermsen, S.A.B.; Kessels, M.Y.; Berg, van den J.H.J.; Peijenburg, A.C.M.; Aarts, J.M.M.J.G.; Piersma, A.H.; Rietjens, I.

2014-01-01

Zebrafish embryos were exposed to concentration ranges of selected thyroid-active model compounds in order to assess the applicability of zebrafish-based developmental scoring systems within an alternative testing strategy to detect the developmental toxicity of thyroid-active compounds. Model

Dispersions of geometric TiO2 nanomaterials and their toxicity to RPMI 2650 nasal epithelial cells

Science.gov (United States)

Tilly, Trevor B.; Kerr, Lei L.; Braydich-Stolle, Laura K.; Schlager, John J.; Hussain, Saber M.

2014-11-01

Titanium dioxide (TiO2) based nanofilaments—nanotube, nanowire, nanorod—have gained interest for industrial, electrical, and as of recent, medical applications due to their superior performance over TiO2 nanoparticles. Safety assessment of these nanomaterials is critical to protect workers, patients, and bystanders as these technologies become widely implemented. Additionally, TiO2 based nanofilaments can easily be inhaled by humans and their high aspect ratio, much like asbestos fibers, may make them toxic in the respiratory system. The tendency of TiO2 nanofilaments to aggregate makes evaluating their nanotoxicity difficult and the results controversial, because incomplete dispersion results in larger particle sizes that are no longer in the nano dimensional size range. TiO2 nanofilaments are aggregated and difficult to disperse homogeneously in solution by conventional methods, such as sonication and vortexing. In this study, a microfluidic device was utilized to produce stable, homogeneous dosing solutions necessary for in vitro toxicity evaluation by eliminating any toxicity caused by aggregated TiO2 nanomaterials. The toxicity results could then be directly correlated to the TiO2 nanostructure itself. The toxicity of four TiO2 nanogeometries—nanotube, nanowire, nanorod, and nanoparticle—were assessed in RPMI 2650 human nasal epithelial cells at representative day, week, and month in vitro exposure dosages of 10, 50, 100 μg/ml, respectively. All TiO2 based nanomaterials dispersed by the microfluidic method were nontoxic to RPMI 2650 cells at the concentrations tested, whereas higher concentrations of 100 μg/ml of nanowires and nanotubes dispersed by sonication reduced viability up to 27 %, indicating that in vitro toxicity results may be controlled by the dispersion of dosing solutions.

Computer Simulation of Developmental Processes and Toxicities (SOT)

Science.gov (United States)

Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic ...

A general mechanism for intracellular toxicity of metal-containing nanoparticles

KAUST Repository

Sabella, Stefania

2014-04-09

The assessment of the risks exerted by nanoparticles is a key challenge for academic, industrial, and regulatory communities worldwide. Experimental evidence points towards significant toxicity for a range of nanoparticles both in vitro and in vivo. Worldwide efforts aim at uncovering the underlying mechanisms for this toxicity. Here, we show that the intracellular ion release elicited by the acidic conditions of the lysosomal cellular compartment-where particles are abundantly internalized-is responsible for the cascading events associated with nanoparticles-induced intracellular toxicity. We call this mechanism a "lysosome-enhanced Trojan horse effect" since, in the case of nanoparticles, the protective cellular machinery designed to degrade foreign objects is actually responsible for their toxicity. To test our hypothesis, we compare the toxicity of similar gold particles whose main difference is in the internalization pathways. We show that particles known to pass directly through cell membranes become more toxic when modified so as to be mostly internalized by endocytosis. Furthermore, using experiments with chelating and lysosomotropic agents, we found that the toxicity mechanism for different metal containing NPs (such as metallic, metal oxide, and semiconductor NPs) is mainly associated with the release of the corresponding toxic ions. Finally, we show that particles unable to release toxic ions (such as stably coated NPs, or diamond and silica NPs) are not harmful to intracellular environments. The Royal Society of Chemistry 2014.

A general mechanism for intracellular toxicity of metal-containing nanoparticles

KAUST Repository

Sabella, Stefania; Carney, Randy P.; Brunetti, Virgilio; Malvindi, Maria Ada; Al-Juffali, Noura; Vecchio, Giuseppe; Janes, Sam M.; Bakr, Osman; Cingolani, Roberto; Stellacci, Francesco; Pompa, Pier Paolo

2014-01-01

The assessment of the risks exerted by nanoparticles is a key challenge for academic, industrial, and regulatory communities worldwide. Experimental evidence points towards significant toxicity for a range of nanoparticles both in vitro and in vivo. Worldwide efforts aim at uncovering the underlying mechanisms for this toxicity. Here, we show that the intracellular ion release elicited by the acidic conditions of the lysosomal cellular compartment-where particles are abundantly internalized-is responsible for the cascading events associated with nanoparticles-induced intracellular toxicity. We call this mechanism a "lysosome-enhanced Trojan horse effect" since, in the case of nanoparticles, the protective cellular machinery designed to degrade foreign objects is actually responsible for their toxicity. To test our hypothesis, we compare the toxicity of similar gold particles whose main difference is in the internalization pathways. We show that particles known to pass directly through cell membranes become more toxic when modified so as to be mostly internalized by endocytosis. Furthermore, using experiments with chelating and lysosomotropic agents, we found that the toxicity mechanism for different metal containing NPs (such as metallic, metal oxide, and semiconductor NPs) is mainly associated with the release of the corresponding toxic ions. Finally, we show that particles unable to release toxic ions (such as stably coated NPs, or diamond and silica NPs) are not harmful to intracellular environments. The Royal Society of Chemistry 2014.

Green Tea Protects Testes against Atrazine-induced Toxicity in Rat

Directory of Open Access Journals (Sweden)

Reza Kheirandish

2017-06-01

Full Text Available Background: Atrazine (ATZ is a common herbicide in agriculture for control of grass and broad-leaved weeds. It persists in the environment and causes reproductive problems in both human and animals. The present study was aimed at protective effect of green tea against ATZ toxicity in the reproductive system of male rats. Methods: The present study was performed in Veterinary School, Shahid Bahonar University of Kerman in 2016. ATZ and treatment groups received ATZ daily 200 mg/kg BW orally for 14 d. In addition, 0.2% methanolic green tea extract was administrated in the treatment group. Results: In histopathologic investigation, number of germinal layers reduced in the most seminiferous tubules in the ATZ group and spermatids were absence. Necrotic spermatocytes, spermatids, and spermatozoa were evident in the testicular tubules. In the morphometric measurements, tubular diameter, germinal epithelium height, and meiosis index decreased significantly. Conclusion: Green tea extract had reduced testicular toxicity of atrazine significantly. ATZ induces toxicity through oxidative damage and green tea extract can protect the testes due to antioxidant activity of its polyphenols especially flavonoids.

Review on toxicity testing with marine macroalgae and the need for method standardization--exemplified with copper and phenol.

Science.gov (United States)

Eklund, Britta T; Kautsky, Lena

2003-02-01

Toxic effects on macroalgae have been compiled. Eighty-two articles have been found in literature during 1959-2000. A total of 120 substances were investigated using 65 different macroalgae species. About one-third of the tested compounds were organic substances (33%), another third metal-organic substances (35%), and the last third were oils (14%), metals (8%), detergents (7.5%) and other inorganic chemicals (2.5%). Half of the substances were only tested once on a single species. Likewise, toxicity data has only been reported for one chemical tested on a single occasion for about half of the 65 species. Thus little is known about the toxic effects on marine macroalgae. The objectives of the previous studies undertaken varied and therefore the toxicity data was presented in numerous ways, e.g. using different exposure times, temperature, light intensity, light regime, salinity, and nutrients, which makes a direct comparison of the data difficult. This review also shows that many stages in the lifecycle of macroalgae are often more sensitive to toxic substances than other aquatic organisms. Consequently, tests using macroalgae may discover toxicity earlier, which would in turn also protect the fauna. If toxic compounds have a negative affect on the distribution and growth of structurally and functionally dominating macroalgae, there may indirectly be a large and harmful influence on the whole marine coastal ecosystem. For this reason tests on macroalgae should be included in control programs along the coasts.

Use of HPLC/UPLC-spectrophotometry for detection of formazan in in vitro Reconstructed human Tissue (RhT)-based test methods employing the MTT-reduction assay to expand their applicability to strongly coloured test chemicals.

Science.gov (United States)

Alépée, N; Barroso, J; De Smedt, A; De Wever, B; Hibatallah, J; Klaric, M; Mewes, K R; Millet, M; Pfannenbecker, U; Tailhardat, M; Templier, M; McNamee, P

2015-06-01

A number of in vitro test methods using Reconstructed human Tissues (RhT) are regulatory accepted for evaluation of skin corrosion/irritation. In such methods, test chemical corrosion/irritation potential is determined by measuring tissue viability using the photometric MTT-reduction assay. A known limitation of this assay is possible interference of strongly coloured test chemicals with measurement of formazan by absorbance (OD). To address this, Cosmetics Europe evaluated use of HPLC/UPLC-spectrophotometry as an alternative formazan measurement system. Using the approach recommended by the FDA guidance for validation of bio-analytical methods, three independent laboratories established and qualified their HPLC/UPLC-spectrophotometry systems to reproducibly measure formazan from tissue extracts. Up to 26 chemicals were then tested in RhT test systems for eye/skin irritation and skin corrosion. Results support that: (1) HPLC/UPLC-spectrophotometry formazan measurement is highly reproducible; (2) formazan measurement by HPLC/UPLC-spectrophotometry and OD gave almost identical tissue viabilities for test chemicals not exhibiting colour interference nor direct MTT reduction; (3) independent of the test system used, HPLC/UPLC-spectrophotometry can measure formazan for strongly coloured test chemicals when this is not possible by absorbance only. It is therefore recommended that HPLC/UPLC-spectrophotometry to measure formazan be included in the procedures of in vitro RhT-based test methods, irrespective of the test system used and the toxicity endpoint evaluated to extend the applicability of these test methods to strongly coloured chemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Toxicity evaluation of chlorinated organic compounds using immortalized rat hepatocytes; Fushika rat kansaibo wo mochiita yuki enso kagobutsu no dokusei hyoka no kokoromi

Energy Technology Data Exchange (ETDEWEB)

Sone, H; Nakajima, M; Yonemoto, J [National Institute for Environmental Studies, Tsukuba (Japan)

1997-11-10

Chlorinated organic compounds has high priority for toxicity screening among environmental hazardous chemicals. In the present study, we used immortalized rat hepatocytes as a liver model in vitro to evaluate the toxicity of nine chlorinated organic compounds. Toxicity of nine chlorinated organic compounds were evaluated to cellular viability of immortalized rat hapatocytes. The potency of the toxicity based on 50% inhibitory concentration (IC50) value was in the following order: triclocalban>triclosan>3,4-dichloroaniline>2,5-diclorophenol> 2,5-dichloroanisole>p-dichlorobenzene> p-chloroaniline>o-dichlorobenzene=tris (2-chloroethyl) phosphate. The rank order of cytotoxic potency of nine chemicals was compared with toxicity information using animals. The rank order of cytotoxic potency did not relative to the order referenced mean lethal dose (LD50) as an index of acute toxicity of rats or mice. However, the rank order of cytotoxic potency relatively correlated non-observed adverse effect level (NOAEL) under the exposure duration adjusted for chronic toxicity in vivo. These data suggests that the origin of testing cell had better to make match target organ of toxic chemicals for extrapolation from data of bioassay in vitro to in vivo. 16 refs., 2 figs., 3 tabs.