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1

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

PubMed

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. PMID:22488763

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

2012-06-01

2

Optimization of high-throughput nanomaterial developmental toxicity testing in zebrafish embryos  

EPA Science Inventory

Nanomaterial (NM) developmental toxicities are largely unknown. With an extensive variety of NMs available, high-throughput screening methods may be of value for initial characterization of potential hazard. We optimized a zebrafish embryo test as an in vivo high-throughput assay...

3

Progress Towards the Development of a Fathead Minnow Embryo Test and Comparison to the Zebrafish Embryo Test for Assessing Acute Fish Toxicity  

EPA Science Inventory

The Zebrafish Embryo Test (ZFET) for acute fish toxicity is a well developed method nearing adoption as an OECD Test Guideline. Early drafts of the test guideline (TG) envisioned a suite of potential test species to be covered including zebrafish, fathead minnow, Japanese Medaka...

4

PAH toxicity at aqueous solubility in the fish embryo test with Danio rerio using passive dosing.  

PubMed

As part of the risk assessment process within REACh, prior to manufacturing and distribution of chemical substances their (eco)toxicological impacts have to be investigated. The fish embryo toxicity test (FET) with the zebrafish Danio rerio has gained a high significance as an in vitro alternative to animal testing in (eco)toxicology. However, for hydrophobic organic chemicals it remains a technical challenge to ensure constant freely dissolved concentration at the maximum exposure level during such biotests. Passive dosing with PDMS silicone was thus applied to control the freely dissolved concentration of ten PAHs at their saturation level in the FET. The experiments gave repeatable results, with the toxicity of the PAHs generally increasing with the maximum chemical activities of the PAHs. HPLC analysis confirmed constant exposure at the saturation level. In additional experiments, fish embryos without direct contact to the silicone surface showed similar mortalities as those exposed with direct contact to the silicone. Silicone oil overlaying the water phase as a novel passive dosing phase had no observable effects on the development of the fish embryos until hatching. This study provides further data to support the close relationship between the chemical activity and the toxicity of hydrophobic organic compounds. Passive dosing from PDMS silicone enabled reliable toxicity testing of (highly) hydrophobic substances at aqueous solubility, providing a practical way to control toxicity exactly at the maximum exposure level. This approach is therefore expected to be useful as a cost-effective initial screening of hydrophobic chemicals for potential adverse effects to freshwater vertebrates. PMID:25048891

Seiler, Thomas-Benjamin; Best, Nina; Fernqvist, Margit Møller; Hercht, Hendrik; Smith, Kilian E C; Braunbeck, Thomas; Mayer, Philipp; Hollert, Henner

2014-10-01

5

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

PubMed

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 (CV<30%) for most chemicals and laboratories. The reproducibility was lower (CV>30%) 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. PMID:24874798

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

6

Simple Test for Toxicity of Number 2 Fuel Oil and Oil Dispersants to Embryos of Grass Shrimp, 'Palaemonetes pugio'.  

National Technical Information Service (NTIS)

A simple test, using embryos of the grass shrimp Palaemonetes pugio, was employed to determine the toxicity of two commercial oil dispersants (Corexit 7664 and Corexit 9527) and toxicity of the water soluble fraction of Number 2 fuel oil (WSF oil) prepare...

W. S. Fisher S. S. Foss

1993-01-01

7

SIMPLE TEST FOR TOXICITY OF NUMBER 2 FUEL OIL AND OIL DISPERSANTS TO EMBRYOS OF GRASS SHRIMP, PALAEMONETES PUGIO  

EPA Science Inventory

A simple test, using embryos of the grass shrimp Palaemonetes pugio, was employed to determine the toxicity of two commercial oil dispersants (Corexit 7664 and Corexit 9527) and toxicity of the water soluble fraction of Number 2 fuel oil (WSF oil) prepared with and without the ad...

8

The fish embryo toxicity test as an animal alternative method in hazard and risk assessment and scientific research  

Microsoft Academic Search

Animal alternatives research has historically focused on human safety assessments and has only recently been extended to environmental testing. This is particularly for those assays that involve the use of fish. A number of alternatives are being pursued by the scientific community including the fish embryo toxicity (FET) test, a proposed replacement alternative to the acute fish test. Discussion of

Michelle R. Embry; Scott E. Belanger; Thomas A. Braunbeck; Malyka Galay-Burgos; Marlies Halder; David E. Hinton; Marc A. Léonard; Adam Lillicrap; Teresa Norberg-King; Graham Whale

2010-01-01

9

Simple test for toxicity of number 2 fuel oil and oil dispersants to embryos of grass shrimp, palaemonetes pugio  

SciTech Connect

A simple test, using embryos of the grass shrimp Palaemonetes pugio, was employed to determine the toxicity of two commercial oil dispersants (Corexit 7664 and Corexit 9527) and toxicity of the water soluble fraction of Number 2 fuel oil (WSF oil) prepared with and without the addition of the dispersants. Tests revealed P. pugio embryos were similar to previously measured life stages in their sensitivity to WSF oil prepared without dispersants. They were approximately ten times more sensitive to water soluble fractions of dispersed oil, which may have been due to the approximately ten-fold increases in total hydrocarbons measured analytically. Both temperatures and salinity of the sea water affected toxicity of WSF prepared with dispersants, the most obvious effect being earlier onset of mortalities at higher temperatures. (Copyright (c) 1993 Pergamon Press Ltd.)

Fisher, W.S.; Foss, S.S.

1993-01-01

10

Large-Scale Assessment of the Zebrafish Embryo as a Possible Predictive Model in Toxicity Testing  

PubMed Central

Background In the drug discovery pipeline, safety pharmacology is a major issue. The zebrafish has been proposed as a model that can bridge the gap in this field between cell assays (which are cost-effective, but low in data content) and rodent assays (which are high in data content, but less cost-efficient). However, zebrafish assays are only likely to be useful if they can be shown to have high predictive power. We examined this issue by assaying 60 water-soluble compounds representing a range of chemical classes and toxicological mechanisms. Methodology/Principal Findings Over 20,000 wild-type zebrafish embryos (including controls) were cultured individually in defined buffer in 96-well plates. Embryos were exposed for a 96 hour period starting at 24 hours post fertilization. A logarithmic concentration series was used for range-finding, followed by a narrower geometric series for LC50 determination. Zebrafish embryo LC50 (log mmol/L), and published data on rodent LD50 (log mmol/kg), were found to be strongly correlated (using Kendall's rank correlation tau and Pearson's product-moment correlation). The slope of the regression line for the full set of compounds was 0.73403. However, we found that the slope was strongly influenced by compound class. Thus, while most compounds had a similar toxicity level in both species, some compounds were markedly more toxic in zebrafish than in rodents, or vice versa. Conclusions For the substances examined here, in aggregate, the zebrafish embryo model has good predictivity for toxicity in rodents. However, the correlation between zebrafish and rodent toxicity varies considerably between individual compounds and compound class. We discuss the strengths and limitations of the zebrafish model in light of these findings.

Ali, Shaukat; van Mil, Harald G. J.; Richardson, Michael K.

2011-01-01

11

Fish embryo toxicity of carbamazepine, diclofenac and metoprolol  

Microsoft Academic Search

Frequently measured pharmaceuticals in environmental samples were tested in fish embryo toxicity (FET) tests with Danio rerio, based on the draft OECD test protocol. In this FET test 2-h-old zebrafish embryos were exposed for 72h to carbamazepine, diclofenac and metoprolol to observe effects on embryo mortality, gastrulation, somite formation, tail movement and detachment, pigmentation, heartbeat, malformation of head, otoliths and

Evert-Jan van den Brandhof; Mark Montforts

2010-01-01

12

Synthesis of low and high chlorinated toxaphene and comparison of their toxicity by zebrafish (Danio rerio) embryo test.  

PubMed

Toxaphene, also known as camphechlor, is a persistent organochlorine pesticide of complex composition. It is technically produced by photochlorination of camphene with elemental chlorine gas under ultraviolet irradiation. In the present work, a novel, laboratory-scale synthesis using sulfuryl chloride as a chlorinating reagent is described. This approach allowed the degree of chlorination of the resulting mixtures to be arbitrarily adjusted by varying the reaction conditions. Both the compositions and the chlorine contents of the low- and high-chlorinated mixtures acquired using this method were similar to those of environmentally altered toxaphene and technical toxaphene, respectively. For comparison of these mixtures regarding toxicity, they were subjected to the zebrafish (Danio rerio) embryo test. Median effective concentrations (EC50s) were calculated based on the presence of lethal and nonlethal embryonic malformations. Surprisingly, low-chlorinated toxaphene, comprising compounds that also are present in environmentally transformed toxaphene, exhibited a twofold-higher toxicity (according to the EC50 for nonlethal effects) toward the test organisms compared with high-chlorinated toxaphene, the composition of which resembled that of the technical product. Although the effective concentrations in the embryo test were much higher than those in aquatic ecosystems burdened with toxaphene, the present results lead to the assumption that toxaphene is becoming more toxic during transformation in the environment. A decrease in the total amount of toxaphene during environmental breakdown would then be compensated for, at least in part, by the higher toxicity of weathered toxaphene in sediments, soils, and biota of contaminated ecosystems. PMID:17089711

Kapp, Thomas; Kammann, Ulrike; Vobach, Michael; Vetter, Walter

2006-11-01

13

The sensitivity and reproducibility of the zebrafish (Danio rerio) embryo test for the screening of waste water quality and for testing the toxicity of chemicals.  

PubMed

The sensitivity of the zebrafish embryo test, a test proposed for routine waste water control, was compared with the acute fish toxicity test, in the determination of six types of waste water and ten different chemicals. The waste water was sampled from the following industrial processes: paper and cardboard production, hide tanning, metal galvanisation, carcass treatment and utilisation, and sewage treatment. The chemicals tested were: dimethylacetamide, dimethylsulphoxide, cadmium chloride, cyclohexane, hydroquinone, mercuric chloride, nickel chloride, nonylphenol, resmethrin and sodium nitrite. For many of the test substances, the zebrafish embryo test and the acute fish toxicity test results showed high correlations. However, there were certain environmentally-relevant substances for which the results of the zebrafish embryo test and the acute fish toxicity test differed significantly, up to 10,000-fold (Hg(2+) > 150-fold difference; NO(2)(-) > 300-fold; Cd(2+) > 200-fold; resmethrin > 10,000-fold). For the investigated waste water samples and chemicals, the survival rate of the zebrafish embryos showed high variations between different egg samples, within the range of the EC50 concentration. Subsequently, 5-6 parallel assays were deemed to be the appropriate number necessary for the precise evaluation of the toxicity of the test substances. Also, it was found that the sensitivities of different ontogenetic stages to chemical exposure differed greatly. During the first 12 hours after fertilisation (4-cell stage to the 5-somite stage), the embryos reacted most sensitively to test substance exposure, whereas the later ontogenetic stages showed only slight or no response, indicating that the test is most sensitive during the first 24 hours post-fertilisation. PMID:18662094

Lahnsteiner, Franz

2008-07-01

14

The zebrafish embryo model in environmental risk assessment—applications beyond acute toxicity testing  

Microsoft Academic Search

Background, aim, and scope  The use of fish embryos is not regulated by current legislations on animal welfare and is therefore considered as a refinement,\\u000a if not replacement of animal experiments. Fish embryos represent an attractive model for environmental risk assessment of\\u000a chemicals since they offer the possibility to perform small-scale, high-throughput analyses.\\u000a \\u000a \\u000a \\u000a Main features  Beyond their application for determining the acute

Stefan Scholz; Stephan Fischer; Ulrike Gündel; Eberhard Küster; Till Luckenbach; Doris Voelker

2008-01-01

15

Toxicity of 15 veterinary pharmaceuticals in zebrafish (Danio rerio) embryos.  

PubMed

Extensive use of veterinary pharmaceuticals may result in contamination of water bodies adjacent to pasture land or areas where animal manure has been applied. In order to evaluate the potential risk to fish embryos 15 veterinary pharmaceuticals were investigated by use of an extended zebrafish embryo toxicity test. Chemical analysis of the exposure medium was performed by solid phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) for 11 of the compounds and potential metabolism by the embryos was studied for albendazole, febantel, fenbendazole and oxfendazole. Newly fertilized zebrafish eggs were exposed under static conditions in 96-well plates for 6 days to the pharmaceuticals: 5 antibacterials and 10 antiparasitics. Endpoints including mortality, malformations and other sublethal responses were recorded at 24, 48 and 144 h post fertilization (hpf). The pharmaceuticals causing the highest toxicity were antiparasitics whereas the tested antibacterials, danofloxacin, enrofloxacin, tylosine, trimethoprim and oxytetracyclin had a much lower toxic potency in zebrafish embryos. Most toxic were fenbendazole, albendazole and flumethrin with no observed effect concentrations (NOECs) around 0.02 mg/L. The overall NOEC was determined by lethality for the following pharmaceuticals: albendazole, fenbendazole and oxfendazole. Sublethal endpoints, including malformations, side-laying embryos, tremors, reduced movements and altered heart rate increased the sensitivity of the tests and determined the overall NOECs for febantel, doramectin, ivermectin, flumethrin and toltrazuril. Exposure to doramectin and ivermectin caused a decrease in movements at 24 hpf and a decrease in heart rate at 48 hpf. Flumethrin exposure resulted in decreased time to hatching, except at the highest concentrations, and caused an increase in heart rate at 48 hpf. In contrast, toltrazuril caused an increased time to hatching and a decrease in heart rate. Chemical analysis of the exposure medium after the tests revealed great differences between nominal and measured concentrations, emphasizing the need of including analysis of the actual exposure concentrations. The results indicated that metabolism of albendazole into its sulfoxide protected the embryos from toxicity. Albendazole was metabolized efficiently into albendazole sulfoxide at lower exposure concentrations, resulting in reduced toxicity. At higher concentrations, an increasing proportion of albendazole remained unmetabolized and embryo mortality occurred. Metabolism by the embryos of febantel into fenbendazole and oxfendazole and of fenbendazole into oxfendazole was demonstrated. It is suggested that the toxic effect of febantel in zebrafish embryos is due to metabolism into fenbendazole. PMID:23142600

Carlsson, Gunnar; Patring, Johan; Kreuger, Jenny; Norrgren, Leif; Oskarsson, Agneta

2013-01-15

16

Extensive review of fish embryo acute toxicities for the prediction of GHS acute systemic toxicity categories.  

PubMed

Distribution and marketing of chemicals require appropriate labelling of health, physical and environmental hazards according to the United Nations global harmonisation system (GHS). Labelling for (human) acute toxicity categories is based on experimental findings usually obtained by oral, dermal or inhalative exposure of rodents. There is a strong societal demand for replacing animal experiments conducted for safety assessment of chemicals. Fish embryos are considered as alternative to animal testing and are proposed as predictive model both for environmental and human health effects. Therefore, we tested whether LC50s of the fish embryo acute toxicity test would allow effectively predicting of acute mammalian toxicity categories. A database of published fish embryo LC50 containing 641 compounds was established. For these compounds corresponding rat oral LD50 were identified resulting in 364 compounds for which both fish embryo LC50 and rat LD50 was available. Only a weak correlation of fish embryo LC50 and rat oral LD50 was obtained. Fish embryos were also not able to effectively predict GHS oral acute toxicity categories. We concluded that due to fundamental exposure protocol differences (single oral dose versus water-borne exposure) a reverse dosimetry approach is needed to explore the predictive capacity of fish embryos. PMID:24929227

Scholz, Stefan; Ortmann, Julia; Klüver, Nils; Léonard, Marc

2014-08-01

17

Comparison of the mouse Embryonic Stem cell Test, the rat Whole Embryo Culture and the Zebrafish Embryotoxicity Test as alternative methods for developmental toxicity testing of six 1,2,4-triazoles  

SciTech Connect

The relatively high experimental animal use in developmental toxicity testing has stimulated the search for alternatives that are less animal intensive. Three widely studied alternative assays are the mouse Embryonic Stem cell Test (EST), the Zebrafish Embryotoxicity Test (ZET) and the rat postimplantation Whole Embryo Culture (WEC). The goal of this study was to determine their efficacy in assessing the relative developmental toxicity of six 1,2,4-triazole compounds, flusilazole, hexaconazole, cyproconazole, triadimefon, myclobutanil and triticonazole. For this purpose, we analyzed effects and relative potencies of the compounds in and among the alternative assays and compared the findings to their known in vivo developmental toxicity. Triazoles are antifungal agents used in agriculture and medicine, some of which are known to induce craniofacial and limb abnormalities in rodents. The WEC showed a general pattern of teratogenic effects, typical of exposure to triazoles, mainly consisting of reduction and fusion of the first and second branchial arches, which are in accordance with the craniofacial malformations reported after in vivo exposure. In the EST all triazole compounds inhibited cardiomyocyte differentiation concentration-dependently. Overall, the ZET gave the best correlation with the relative in vivo developmental toxicities of the tested compounds, closely followed by the EST. The relative potencies observed in the WEC showed the lowest correlation with the in vivo developmental toxicity data. These differences in the efficacy between the test systems might be due to differences in compound kinetics, in developmental stages represented and in the relative complexity of the alternative assays.

Jong, Esther de, E-mail: Esther.de.Jong@rivm.nl [Institute for Risk Assessment Sciences, Utrecht University, Utrecht (Netherlands); Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Barenys, Marta [GRET-CERETOX, Toxicology Unit, Public Health Department, School of Pharmacy, University of Barcelona, Barcelona (Spain); Hermsen, Sanne A.B. [Institute for Risk Assessment Sciences, Utrecht University, Utrecht (Netherlands); Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Health Risk Analysis and Toxicology, NUTRIM, University of Maastricht, Maastricht (Netherlands); Verhoef, Aart [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Ossendorp, Bernadette C.; Bessems, Jos G.M. [Centre for Substances and Integrated Risk Assessment, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Piersma, Aldert H. [Institute for Risk Assessment Sciences, Utrecht University, Utrecht (Netherlands); Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands)

2011-06-01

18

Comparison of the mouse Embryonic Stem cell Test, the rat Whole Embryo Culture and the Zebrafish Embryotoxicity Test as alternative methods for developmental toxicity testing of six 1,2,4-triazoles.  

PubMed

The relatively high experimental animal use in developmental toxicity testing has stimulated the search for alternatives that are less animal intensive. Three widely studied alternative assays are the mouse Embryonic Stem cell Test (EST), the Zebrafish Embryotoxicity Test (ZET) and the rat postimplantation Whole Embryo Culture (WEC). The goal of this study was to determine their efficacy in assessing the relative developmental toxicity of six 1,2,4-triazole compounds,(1) flusilazole, hexaconazole, cyproconazole, triadimefon, myclobutanil and triticonazole. For this purpose, we analyzed effects and relative potencies of the compounds in and among the alternative assays and compared the findings to their known in vivo developmental toxicity. Triazoles are antifungal agents used in agriculture and medicine, some of which are known to induce craniofacial and limb abnormalities in rodents. The WEC showed a general pattern of teratogenic effects, typical of exposure to triazoles, mainly consisting of reduction and fusion of the first and second branchial arches, which are in accordance with the craniofacial malformations reported after in vivo exposure. In the EST all triazole compounds inhibited cardiomyocyte differentiation concentration-dependently. Overall, the ZET gave the best correlation with the relative in vivo developmental toxicities of the tested compounds, closely followed by the EST. The relative potencies observed in the WEC showed the lowest correlation with the in vivo developmental toxicity data. These differences in the efficacy between the test systems might be due to differences in compound kinetics, in developmental stages represented and in the relative complexity of the alternative assays. PMID:21443896

de Jong, Esther; Barenys, Marta; Hermsen, Sanne A B; Verhoef, Aart; Ossendorp, Bernadette C; Bessems, Jos G M; Piersma, Aldert H

2011-06-01

19

Toxic effects of colloidal nanosilver in zebrafish embryos.  

PubMed

A variety of consumer products containing silver nanoparticles (Ag NPs) are currently marketed. However, their safety for humans and for the environment has not yet been established and no standard method to assess their toxicity is currently available. The objective of this work was to develop an effective method to test Ag NP toxicity and to evaluate the effects of ion release and Ag NP size on a vertebrate model. To this aim, the zebrafish animal model was exposed to a solution of commercial nanosilver. While the exposure of embryos still surrounded by the chorion did not allow a definite estimation of the toxic effects exerted by the compound, the exposure for 48 h of 3-day-old zebrafish hatched embryos afforded a reliable evaluation of the effects of Ag NPs. The effects of the exposure were detected especially at molecular level; in fact, some selected genes expressed differentially after the exposure. The Ag NP toxic performance was due to the combined effect of Ag(+) ion release and Ag NP size. However, the effect of NP size was particularly detectable at the lowest concentration of nanosilver tested (0.01 mg l(-1)) and depended on the solubilization media. The results obtained indicate that in vivo toxicity studies of nanosilver should be performed with ad hoc methods (in this case using hatched embryos) that might be different depending on the type of nanosilver. Moreover, the addition of this compound to commercial products should take into consideration the Ag NP solubilization media. PMID:24395442

Olasagasti, Maider; Gatti, Antonietta M; Capitani, Federico; Barranco, Alejandro; Pardo, Miguel Angel; Escuredo, Kepa; Rainieri, Sandra

2014-05-01

20

Toxicity of trihalomethanes to common carp embryos  

SciTech Connect

Trihalomethanes recently have been identified in real and simulated effluents from power plants where chlorine is used for biofouling control. Toxicity of the four chlorine- or bromine-containing trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) to developing common carp (Cyprinus carpio) embryos was determined under conditions of intermittent (8-hour) toxicant renewal, based on percent hatch as the end point. Nominal median lethal concentrations (LC50) ranged from 161 mg/liter for chloroform to 53 mg/liter for dibromochloromethane. Decay studies conducted under conditions similar to those used for the toxicity studies, but in distilled water, indicated that (1) half-lives of the trihalomethanes ranged from 4.4 to 6.9 hours; (2) decay was due primarily to volatilization; (3) higher relative toxicity of dibromochloromethane probably was due to formation of a degradation product (likely Br/sub 2/). Correction of the nominal LC50 values to time-weighted mean concentrations over the period between toxicant changes gave weighted LC50 values of 97.2, 67.4, 33.5, and 52.3 mg/liter for chloroform, bromodichloromethane, dibromochloromethane, and bromoform, respectively. In addition, the period of water-hardening of fertilized eggs was not critical for expression of toxicity of dibromochloromethane. Comparison of these and other published data on effluent and toxic concentrations, persistence, and bioaccumulation of water-chlorination products suggests that trihalomethanes are not as environmentally critical as other chlorinated organic compounds or residual chlorine.

Mattice, J.S. (Oak Ridge National Lab., TN); Tsai, S.C.; Burch, M.B.; Beauchamp, J.J.

1981-03-01

21

Toxicity of organic compounds to marine invertebrate embryos and larvae: a comparison between the sea urchin embryogenesis bioassay and alternative test species.  

PubMed

This study investigated the toxic effects of the insecticides lindane and chlorpyrifos, the herbicide diuron, the organometallic antifoulant tributyltin (TBT), and the surfactant sodium dodecyl sulfate (SDS) on the early life stages of Paracentrotus lividus (Echinodermata, Euechinoidea), Ciona intestinalis (Chordata, Ascidiacea), Maja squinado and Palaemon serratus (Arthropoda, Crustacea) in laboratory acute toxicity tests. The assays studied embryogenesis success from fertilized egg to normal larvae in P. lividus (48 h incubation at 20 degrees C) and C. intestinalis (24 h incubation at 20 degrees C), and larval mortality at 24 and 48 h in M. squinado and P. serratus. For P. lividus, the median effective concentrations (EC50) reducing percentages of normal larvae by 50% were: 350 microg l(-1) for chlorpyrifos, 5500 microg l(-1) for diuron, 4277 microg l(-1) for SDS, and 0.309 microg l(-1) for TBT. For C. intestinalis, the EC50 values affecting embryogenesis success were 5666 microg l(-1) for chlorpyrifos, 24,397 microg (l-1) for diuron, 4412 microg l(-1) for lindane, 5145 microg I(-1) for SDS, and 7.1 microg l(-1) for TBT. The median lethal concentrations (LC50) for M. squinado larval survival were 0.84 microg l(-1) (24 h) and 0.79 microg l(-1) (48 h) for chlorpyrifos, 2.23 microg(l(-1) (24 h) and 2.18 microg l(-1) (48 h) for lindane, and 687 microg l(-1) (48 h) for SDS. For P. serratus the LC50 values obtained were 0.35 microg l(-1) (24 h) and 0.22 microg l(-1) (48 h) for chlorpyrifos, 3011 microg l(-1) (24 h) and 3044 microg l(-1) (48 h) for diuron, 5.20 microg l(-1) (24 h) and 5.59 microg l(-1) (48 h) for lindane, and 22.30 microg l(-1) (24 h) and 17.52 microg l(-1) (48 h) for TBT. Decapod larvae, as expected, were markedly more sensitive to the insecticides than sea urchins and ascidians, and SDS was the least toxic compound tested for these organisms. Lowest observed effect concentrations (LOEC) of TBT for sea urchin and ascidian embryos, chlorpyrifos and lindane for crustacean larvae, and SDS, were similar to those found in many coastal areas indicating that there would be a risk to invertebrate embryos and larvae from exposure in the field to these pollutants. PMID:15943109

Bellas, Juan; Beiras, Ricardo; Mariño-Balsa, José Carlos; Fernández, Nuria

2005-04-01

22

Evaluation of acute toxicity and teratogenic effects of plant growth regulators by Daphnia magna embryo assay.  

PubMed

This study selected common plant growth regulators (Atonik, Cytokinin, Ethephon, Gibberellic acid and Paclobutrazol) to investigate their biological toxicity to the waters of the important biological indicator Daphnia magna. The methods used in this study included traditional neonate acute toxicity test, new Daphnia embryo toxicity test, and teratogenic embryo test. The study concluded that the acute toxicity of the five PGRs to Daphnia neonate had EC(50) value range of 1.9-130.5 mg l(-1), while acute toxicity of PGRs on Daphnia embryo had EC(50) value range of 0.2-125 mg l(-1); the Daphnia embryos' LOEC values (0.05-48 mg l(-1)) for the five PGRs were lower than embryo EC(50) values. The toxic ratios of 48 h EC(50) (neonate)/48 h LOEC (embryo) for 5 PGRs were 19-512 times. The study found that teratogenic effects of Paclobutrazol and Cytokinin induced in embryo were higher than those of most other PGRs. Microscopic observation of the teratogenic effects showed that all 5 PGRs induced malformations of the second antenna, rostrum, Malpighian tube, sensory bristles, and tail spine as well as function loss and death. PMID:21514995

Wang, Kai-Sung; Lu, Chi-Yuan; Chang, Shih-Hsien

2011-06-15

23

The toxic effects of pyrethroid deltamethrin on the common carp ( Cyprinus carpio L.) embryos and larvae  

Microsoft Academic Search

Deltamethrin, a synthetic pyrethroid pesticide contaminating aquatic ecosystems as a pollutant, was investigated in the present study for toxic effects on embryos and larvae of common carp, Cyprinus carpio as a model. The control and five test experiments were repeated five times. The water temperature in the experimental units was kept at 24±1°C. The number of dead embryos significantly increased

Kenan Köprücü; Rahmi Ayd?n

2004-01-01

24

Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae  

PubMed Central

Silica nanoparticles (SiNPs) have been widely used in biomedical and biotechnological applications. Environmental exposure to nanomaterials is inevitable as they become part of our daily life. Therefore, it is necessary to investigate the possible toxic effects of SiNPs exposure. In this study, zebrafish embryos were treated with SiNPs (25, 50, 100, 200 µg/mL) during 4–96 hours post fertilization (hpf). Mortality, hatching rate, malformation and whole-embryo cellular death were detected. We also measured the larval behavior to analyze whether SiNPs had adverse effects on larvae locomotor activity. The results showed that as the exposure dosages increasing, the hatching rate of zebrafish embryos was decreased while the mortality and cell death were increased. Exposure to SiNPs caused embryonic malformations, including pericardial edema, yolk sac edema, tail and head malformation. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lower dose (25 and 50 µg/mL SiNPs) produced substantial hyperactivity while the higher doses (100 and 200 µg/mL SiNPs) elicited remarkably hypoactivity in dark periods. In summary, our data indicated that SiNPs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior.

Shi, Huiqin; Tian, Linwei; Guo, Caixia; Huang, Peili; Zhou, Xianqing; Peng, Shuangqing; Sun, Zhiwei

2013-01-01

25

Rapid aquatic toxicity assay utilizing labeled thymidine incorporation in sea urchin embryos  

Microsoft Academic Search

Aquatic toxicity was evaluated in the sea urchin embryo (Arbacea punctulata) by the inhibition of tritiated thymidine incorporation after a brief exposure to toxic chemicals. Arbacia is a useful surrogate species for assay: well-studied, easily cultured and fertile virtually year round. The simplicity and speed of this test system lends itself to screening large numbers of compounds, mixtures or water

Eugene Jackim; Diane Nacci

1984-01-01

26

Oil and oil dispersant do not cause synergistic toxicity to fish embryos.  

PubMed

Atlantic herring (Clupea harengus) embryos were exposed to water accommodated fractions (WAFs; oil dissolved in water) and chemically enhanced water accommodated fractions (CEWAFs; oil dispersed in water with Corexit 9500A) of Medium South American (MESA) crude oil. The CEWAF was approximately 100-fold more toxic than WAF based on nominal loadings of test solutions (% v/v). In contrast, the ratio of WAF and CEWAF toxicity expressed as measured oil concentrations approximated 1.0, indicating that the higher toxicity of CEWAFs was caused by an increase in exposure to hydrocarbons with chemical dispersion. In a second experiment, the chronic toxicity of Corexit 9500A and chemically dispersed heavy fuel oil 7102 (HFO 7102) to rainbow trout (Oncorhynchus mykiss) embryos was compared to chemically dispersed Nujol, a nontoxic mineral oil. Dispersant alone was toxic, but caused different signs of toxicity than HFO 7102. Nujol at a dispersant-to-oil ratio of 1:20 was nontoxic, suggesting that dispersant was sequestered by oil and not present at toxic concentrations. In contrast, the same nominal loadings of dispersed HFO 7102 caused concentration-dependent increases in toxicity. Both experiments suggest that chemically dispersed oil was more toxic to fish embryos than solutions created by mechanical mixing due to the increased exposure of fish to petroleum hydrocarbons and not to changes in hydrocarbon toxicity. The Nujol control discriminated between the toxicity of oil and chemical dispersant and would be a practical addition to programs of dispersant testing. PMID:24115182

Adams, Julie; Sweezey, Michael; Hodson, Peter V

2014-01-01

27

Sediment toxicity assessment in the Lagoon of Venice (Italy) using Paracentrotus lividus (Echinodermata: Echinoidea) fertilization and embryo bioassays  

Microsoft Academic Search

The capacity of two toxicity bioassays (fertilization and embryo toxicity tests) to discriminate sediment toxicity using the sea urchin Paracentrotus lividus was tested in five stations with different levels of pollution in the Lagoon of Venice. Two stations were located in estuarine sites, two in the industrial zone, and one in a site at the top of our quality gradient

A. Volpi Ghirardini; A. Arizzi Novelli; D. Tagliapietra

2005-01-01

28

DEVELOPMENT OF ISOLATED MAMMALIAN EMBRYO TECHNIQUES FOR TOXIC SUBSTANCES SCREENING  

EPA Science Inventory

A potential screen for assessing teratogenic potential of compounds in mammals was tested. The technique involves testing isolated mammalian embryos in culture by direct exposure to agents. Embryos from three species of mammals were used; the mouse, rabbit and swine. Four differe...

29

DEVELOPMENTAL TOXICITY OF COPPER SULFATE AND METHYLENE CHLORIDE TO SHRIMP EMBRYOS  

EPA Science Inventory

The embryos of the grass shrimp (Palaemonetes pugio) have shown sensitivity to the water-soluble fraction of Number 2 fuel oil which indicates they may be a useful test species in estuarine developmental toxicity tests. Detailed concentration-response curves for copper sulfate an...

30

Chronic toxicity of copper on embryo development in Chinese toad, Bufo gargarizans.  

PubMed

This study examined the effects of copper exposure on embryonic development of Chinese toad, Bufo gargarizans. Firstly, the LC(50) values from 24 to 96 h of exposure were 3.61×10(-6) M, by means of a 4 d toxicity test with B. gargarizans embryos. Secondly, Chinese toad embryos were exposed to 10(-9)-10(-6) M copper from mid gastrula stage to operculum completion stage. Measurements included mortality, tadpole weight, tadpole total length, growth retardation, duration of different embryo stages and malformation. Embryonic survival was not affected by copper. Relative to control tadpoles, significantly decreased weight and total length were found at 10(-9)-10(-6) M reduced percentage of the embryos in right operculum stage after 10 d exposure to copper and reduced percentage of embryos in operculum completion stage after 12 d exposure to copper were also observed. Moreover, the duration of embryonic development increased at neural, circulation and operculum development stage in copper-treated groups. For the scanning microscope and histological observation, the abnormalities were malformation of wavy dorsal fin, flexural tail, curvature body axis, yolk sac oedema and reduced pigmentation in the yolk sac. Histopathological changes in olfactory, retinal epithelium and skin were also observed. DNA strand breaks exposed to the copper were analyzed by DNA ladder. In conclusion, copper induced toxic effects on B. gargarizans embryos. The present study indicated chronic toxicity tests may provide more accurate way in formulating the "safe levels" of heavy metals to amphibian. PMID:22436585

Xia, Kun; Zhao, Hongfeng; Wu, Minyao; Wang, Hongyuan

2012-06-01

31

Developmental toxicity and brain aromatase induction by high genistein concentrations in zebrafish embryos  

PubMed Central

Genistein is a phytoestrogen found at a high level in soybeans. In vitro and in vivo studies showed that high concentrations of genistein caused toxic effects. This study was designed to test the feasibility of zebrafish embryos for evaluating developmental toxicity and estrogenic potential of high genistein concentrations. The zebrafish embryos at 24 h post-fertilization were exposed to genistein (1 × 10?4 M, 0.5 × 10?4 M, 0.25 × 10?4 M) or vehicle (ethanol, 0.1%) for 60 h. Genistein-treated embryos showed decreased heart rates, retarded hatching times, decreased body length, and increased mortality in a dose-dependent manner. After 0.25 × 10?4 M genistein treatment, malformations of survived embryos such as pericardial edema, yolk sac edema, and spinal kyphosis were also observed. TUNEL assay results showed apoptotic DNA fragments in brain. This study also confirmed the estrogenic potential of genistein by EGFP expression in the brain of the mosaic reporter zebrafish embryos. This study first demonstrated that high concentrations of genistein caused a teratogenic effect on zebrafish embryos and confirmed the estrogenic potential of genistein in mosaic reporter zebrafish embryos.

Kim, Dong-Jae; Seok, Seung-Hyeok; Baek, Min-Won; Lee, Hui-Young; Na, Yi-Rang; Park, Sung-Hoon; Lee, Hyun-Kyoung; Dutta, Noton Kumar; Kawakami, Koichi; Park, Jae-Hak

2009-01-01

32

Nanomaterial Toxicity Screening in Developing Zebrafish Embryos  

EPA Science Inventory

To assess nanomaterial vertebrate toxicity, a high-content screening assay was created using developing zebrafish, Danio rerio. This included a diverse group of nanomaterials (n=42 total) ranging from metallic (Ag, Au) and metal oxide (CeO2, CuO, TiO2, ZnO) nanoparticles, to non...

33

DEVELOPMENTAL TOXICITY TESTING  

EPA Science Inventory

Contemporary developmental toxicity testing focuses on the evaluation of a variety of adverse developmental effects which include structural malformations, intrauterine death, growth retardation, and deficits in postnatal function. n the extrapolation of information from animal s...

34

Marine Sediment Toxicity Tests.  

National Technical Information Service (NTIS)

Sediment toxicity tests have been developed on the basis of virtually all levels of biological organization from sub-cellular through model ecosystems. Rapid, cost-effective techniques based on acute exposures are often used in research and regulatory pro...

R. C. Swartz

1989-01-01

35

Testing the embryo, testing the fetus  

PubMed Central

This paper stems from an ethnographic, multidisciplinary study that explored the views and experiences of practitioners and scientists on social, ethical and clinical dilemmas encountered when working in the area of PGD for serious genetic disorders. We focus here on staff perceptions and experiences of working with embryos and helping women/couples to make choices that will result in selecting embryos for transfer and disposal of ‘affected’ embryos, compared to the termination of affected pregnancies following PND. Analysis and discussion of our data led us to consider the possible advantages of PGD and whether a gradualist account of the embryo’s and fetus’s moral status can account for all of these, particularly since a gradualist account concentrates on the significance of time (developmental stage) and makes no comment as to the significance of place (in-vitro, in-utero).

Ehrich, K; Farsides, B; Williams, C; Scott, Rosamund

2008-01-01

36

ENGINEERING BULLETIN: BIOLOGICAL TOXICITY TESTING  

EPA Science Inventory

This Engineering Bulletin is intended to provide site managers with information on ecological assessment and biological toxicity testing, applicability of biological toxicity testing, planning effective biological toxicity assessments, descriptions of test methods, limitations, c...

37

In Vivo Nanotoxicity Testing using the Zebrafish Embryo Assay  

PubMed Central

Nanoparticles are increasingly used for biomedical purposes. Many different diagnostic and therapeutic applications are envisioned for nanoparticles, but there are often also serious concerns regarding their safety. Given the fact that numerous new nanomaterials are being developed every day, and that not much is known about the long-term toxicological impact of exposure to nanoparticles, there is an urgent need to establish efficient methods for nanotoxicity testing. The zebrafish (Danio rerio) embryo assay has recently emerged as an interesting ‘intermediate’ method for in vivo nanotoxicity screening, enabling (semi-) high-throughput analyses in a system significantly more complex than cultured cells, but at the same time also less ‘invasive’ and less expensive than large-scale biocompatibility studies in mice or rats. The zebrafish embryo assay is relatively well-established in the environmental sciences, but it has not yet gained wide notice in the nanomedicine field. Using prototypic polymeric drug carriers, gold-based nanodiagnostics and nanotherapeutics, and iron oxide-based nanodiagnostics, we here show that toxicity testing using zebrafish embryos is easy, efficient and informative, and faithfully reflects, yet significantly extends, cell-based toxicity testing. We therefore expect that the zebrafish embryo assay will become a popular future tool for in vivo nanotoxicity screening.

Rizzo, Larissa Y.; Golombek, Susanne K.; Mertens, Marianne E.; Pan, Yu; Laaf, Dominic; Broda, Janine; Jayapaul, Jabadurai; Mockel, Diana; Subr, Vladimir; Hennink, Wim E.; Storm, Gert; Simon, Ulrich; Jahnen-Dechent, Willi; Kiessling, Fabian; Lammers, Twan

2013-01-01

38

Tissue-specific direct microtransfer of nanomaterials into Drosophila embryos as a versatile in vivo test bed for nanomaterial toxicity assessment.  

PubMed

Nanomaterials are the subject of intense research, focused on their synthesis, modification, and biomedical applications. Increased nanomaterial production and their wide range of applications imply a higher risk of human and environmental exposure. Unfortunately, neither environmental effects nor toxicity of nanomaterials to organisms are fully understood. Cost-effective, rapid toxicity assays requiring minimal amounts of materials are needed to establish both their biomedical potential and environmental safety standards. Drosophila exemplifies an efficient and cost-effective model organism with a vast repertoire of in vivo tools and techniques, all with high-throughput scalability and screening feasibility throughout its life cycle. Here we report tissue specific nanomaterial assessment through direct microtransfer into target tissues. We tested several nanomaterials with potential biomedical applications such as single-wall carbon nanotubes, multiwall carbon nanotubes, silver, gold, titanium dioxide, and iron oxide nanoparticles. Assessment of nanomaterial toxicity was conducted by evaluating progression through developmental morphological milestones in Drosophila. This cost-effective assessment method is amenable to high-throughput screening. PMID:24790441

Vega-Alvarez, Sasha; Herrera, Adriana; Rinaldi, Carlos; Carrero-Martínez, Franklin A

2014-01-01

39

Tissue-specific direct microtransfer of nanomaterials into Drosophila embryos as a versatile in vivo test bed for nanomaterial toxicity assessment  

PubMed Central

Nanomaterials are the subject of intense research, focused on their synthesis, modification, and biomedical applications. Increased nanomaterial production and their wide range of applications imply a higher risk of human and environmental exposure. Unfortunately, neither environmental effects nor toxicity of nanomaterials to organisms are fully understood. Cost-effective, rapid toxicity assays requiring minimal amounts of materials are needed to establish both their biomedical potential and environmental safety standards. Drosophila exemplifies an efficient and cost-effective model organism with a vast repertoire of in vivo tools and techniques, all with high-throughput scalability and screening feasibility throughout its life cycle. Here we report tissue specific nanomaterial assessment through direct microtransfer into target tissues. We tested several nanomaterials with potential biomedical applications such as single-wall carbon nanotubes, multiwall carbon nanotubes, silver, gold, titanium dioxide, and iron oxide nanoparticles. Assessment of nanomaterial toxicity was conducted by evaluating progression through developmental morphological milestones in Drosophila. This cost-effective assessment method is amenable to high-throughput screening.

Vega-Alvarez, Sasha; Herrera, Adriana; Rinaldi, Carlos; Carrero-Martinez, Franklin A

2014-01-01

40

Developmental toxicity of dextromethorphan in zebrafish embryos/larvae.  

PubMed

Dextromethorphan is widely used in over-the-counter cough and cold medications. Its efficacy and safety for infants and young children remains to be clarified. The present study was designed to use zebrafish as a model to investigate the potential toxicity of dextromethorphan during embryonic and larval development. Three sets of zebrafish embryos/larvae were exposed to dextromethorphan at 24, 48 and 72?h post fertilization (hpf), respectively, during the embryonic/larval development. Compared with the 48 and 72?hpf exposure sets, the embryos/larvae in the 24?hpf exposure set showed much higher mortality rates which increased in a dose-dependent manner. Bradycardia and reduced blood flow were observed for the embryos/larvae treated with increasing concentrations of dextromethorphan. Morphological effects of dextromethorphan exposure, including yolk sac and cardiac edema, craniofacial malformation, lordosis, non-inflated swim bladder and missing gill, were also more frequent and severe among zebrafish embryos/larvae exposed to dextromethorphan at 24?hpf. Whether the more frequent and severe developmental toxicity of dextromethorphan observed among the embryos/larvae in the 24?hpf exposure set, as compared with the 48 and 72?hpf exposure sets, is due to the developmental expression of the phase I and phase II enzymes involved in the metabolism of dextromethorphan remains to be clarified. A reverse transcription-polymerase chain reaction analysis, nevertheless, revealed developmental stage-dependent expression of mRNAs encoding SULT3 ST1 and SULT3 ST3, two enzymes previously shown to be capable of sulfating dextrorphan, an active metabolite of dextromethorphan. PMID:20737414

Xu, Zheng; Williams, Frederick E; Liu, Ming-Cheh

2011-03-01

41

Testing the embryo, testing the fetus.  

PubMed

This paper stems from an ethnographic, multidisciplinary study that explored the views and experiences of practitioners and scientists on social, ethical and clinical dilemmas encountered when working in the area of PGD for serious genetic disorders. We focus here on staff perceptions and experiences of working with embryos and helping women/couples to make choices that will result in selecting embryos for transfer and disposal of 'affected' embryos, compared to the termination of affected pregnancies following PND. Analysis and discussion of our data led us to consider the possible advantages of PGD and whether a gradualist account of the embryo's and fetus's moral status can account for all of these, particularly since a gradualist account concentrates on the significance of time (developmental stage) and makes no comment as to the significance of place (in-vitro, in-utero). PMID:18516224

Ehrich, K; Farsides, B; Williams, C; Scott, Rosamund

2007-12-01

42

[Interaction between calcium and lead affects the toxicity to embryo of zebrafish (Danio rerio)].  

PubMed

This study tested the hypothesis that increased Ca2+ content increases the sensitivity of the developing embryos and larvae of zebrafish (Danio rerio) to Pb. And the aim of the study was to investigate the extent to which calcium can individually mitigate lead ion toxicity based on the concept of biotic ligand model (BLM). Embryos of the zebrafish were exposed to various Pb concentrations. Chemical characteristics of water and representative toxicological endpoints of zebrafish embryo were recorded. And general growth retardation as a major toxicological endpoint was used for analysis at 72 h due to its sensitivity and facility. The BLM software of Visual MINTEQ (Version 2.5.2) was employed to calculate the chemical speciation in the solution. The results showed that when Ca2+ concentration increased from 0.25 mmol/L to 2.00 mmol/L, the toxicity of lead on embryos of zebrafish (Danio rerio) decreased markedly after 72 h. And a large part of these decrease can be explained by the positive linear relations between EC50{Pb2+}/EC50[Pb]T (expressed as lead ion activity/dissolved total concentration) and activity/total concentration of Ca2+, through which the influence of Ca2+ on toxicity could be predicted. The results support the assumptions of the BLM and associated with competition between lead and calcium for binding on transport and toxic action sites on biological surfaces. However, when Ca2+ concentration increased from 2.00 mmol/L to 4.00 mmol/L, the toxicity of lead on embryos of zebrafish (Danio rerio) seemed to be constant at 72 h. PMID:19545030

Chen, Zhong-Zhi; Zhu, Lin; Yao, Kun; Wang, Xiu-Juan; Ding, Jun-Nan

2009-04-15

43

Toxicity of urban highway runoff in Shanghai to Zebrafish (Danio rerio ) embryos and luminous bacteria (Vibrio qinghaiensis.Q67).  

PubMed

Pollution from urban highway runoff has been identified as one of the major causes of the deterioration of receiving water quality. The purpose of this study is to assess the toxicity of urban storm water samples in Shanghai using the zebrafish (Danio rerio ) embryo test and the bacterial luminescence (Vibrio qinghaiensis ) assay. The toxicity of highway runoff from seventeen storm events was investigated in both grab and composite samples. Zebrafish embryos were exposed to the runoff samples and development parameters including lethality, spontaneous movements in 20 s, heart beat rate, hatching rate, and abnormality of zebrafish embryos were observed after 24, 48, 72, and 96 h of exposure. Inhibition rates of luminescence intensity were also recorded. The results showed that in the zebrafish embryo toxicity tests, both grab and composite samples increased the lethality, reduced the percentage with spontaneous movements and heart beats, inhibited the hatching of embryos, and induced morphological abnormalities. In the Vibrio qinghaiensis toxicity test, all the grab samples inhibited the luminescence, while some of the composite samples promoted it, which indicated that different types of toxicants might have been affecting the species. The multivariate statistics analysis indicated that heavy metal (zinc, manganese, and copper) and PAHs might mainly contribute to the toxicity of runoff samples. PMID:24122161

Wu, Lingling; Jiang, Yue; Zhang, Lili; Chen, Ling; Zhang, Haiping

2014-02-01

44

Japanese medaka (Oryzias latipes) embryo assay for developmental toxicity incorporating individual embryo incubations: Evaluations of controls, a pure compound (BaP), soil extracts, and stream effluents  

SciTech Connect

A non-indigenous, but useful fish species has been largely overlooked by organizations preparing protocols for toxicity testing in research and environmental regulation. The Japanese medaka (Oryzias latipes) has been used in basic and applied research in the United States and Japan for many years. All life-history stages have been used and studied, including numerous different types of embryo and embryo-larval assays. However, a medaka embryo assay has yet to be recommended by the American Society for Testing and Materials, the United States Environmental Protection Agency or the American Public Health Association for use as a test species in water quality control. The authors have developed and refined methods for evaluating toxicity and abnormalities in embryos exposed to contaminants in a variety of media. Individual embryos exposed to benzo[a]pyrene showed both increased mortalities and abnormalities. In the two field applications, individual embryos were exposed to: (1) soil extracts from two hydrocarbon-contaminated sites on U.S. Army Kwajalein Atoll, in the General Republic of the Marshall Islands, or (2) water samples from ten sites on East Fork Poplar Creek, in Oak Ridge, TN, a stream that originates inside the DOE Y-12 Plant. The two soil extracts were from diesel fuel-contaminated soil; treated embryos showed significant responses ranging from increased mortalities to abnormalities and developmental delays. The stream has a history of industrial contamination, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and heavy metals, (particularly mercury); other typical industrial discharges (i.e. chlorine, ammonia, and nitrates) are also present at some sites. Treatment groups showed high mortality and dose-dependent mortality in diluted samples compared to control and reference water samples. This study demonstrates the flexibility of this medaka embryo assay for assessing the toxicity of complex environmental sites.

Hull, C.G.

1993-01-01

45

Developmental toxicity of 2-chlorodibenzofuran in cultured post-implantation rat embryos.  

PubMed

The developmental toxicity of 2-chlorodibenzofuran (2-MCDF), a contaminant in tap water, was examined by using post-implantation rat embryo culture with or without a metabolic activation system. 3-Chlorodibenzofuran (3-MCDF) and dibenzofuran (DF) were examined for comparison. Rat embryos at day 9 of gestation were cultured for 48 hr in the presence of the test chemicals (0, 30, 100, 300 or 1000 mum). 2-MCDF inhibited embryonic growth and increased morphological abnormalities of the embryos at 1000 mum in either the presence or absence of the metabolic activation system. The chief abnormalities were unclosed posterior neuropore and coelomic haemorrhage. Similar effects were observed in the embryos treated with 3-MCDF or DF. Dosing of 2-MCDF at maternotoxic levels to pregnant rats from days 9 to 11 of gestation, however, had no effect on the embryo-foetal development in vivo. It was concluded from these results that 2-MCDF had weak-inactive teratogenicity and that there was little risk to human embryos at the concentrations in tap water. It appeared that the embryotoxicity of 2-MCDF was caused by the dibenzofuran structure through mechanisms independent of DNA damage and the Ah receptor. PMID:20732197

Usami, M; Sakemi, K; Tabata, H; Kawashima, K; Takanaka, A

1993-05-01

46

Effects-driven chemical fractionation of heavy fuel oil to isolate compounds toxic to trout embryos.  

PubMed

Heavy fuel oil (HFO) spills account for approximately 60% of ship-source oil spills and are up to 50 times more toxic than medium and light crude oils. Heavy fuel oils contain elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and alkyl-PAHs, known to be toxic to fish; however, little direct characterization of HFO toxicity has been reported. An effects-driven chemical fractionation was conducted on HFO 7102 to separate compounds with similar chemical and physical properties, including toxicity, to isolate the groups of compounds most toxic to trout embryos. After each separation, toxicity tests directed the next phase of fractionation, and gas chromatography-mass spectrometry analysis correlated composition with toxicity, with a focus on PAHs. Low-temperature vacuum distillation permitted the separation of HFO into 3 fractions based on boiling point ranges. The most toxic of these fractions underwent wax precipitation to remove long-chain n-alkanes. The remaining PAH-rich extract was further separated using open column chromatography, which provided distinct fractions that were grouped according to increasing aromatic ring count. The most toxic of these fractions was richest in PAHs and alkyl-PAHs. The results of the present study were consistent with previous crude oil studies that identified PAH-rich fractions as the most toxic. Environ Toxicol Chem 2014;33:814-824. © 2013 SETAC. PMID:24375845

Bornstein, Jason M; Adams, Julie; Hollebone, Bruce; King, Thomas; Hodson, Peter V; Brown, R Stephen

2014-04-01

47

Acute toxicity of agricultural pesticides to embryo-larval and juvenile African catfish Clarias gariepinus.  

PubMed

Acute toxicities of Tihan 175 O-TEQ, as well as its active ingredients flubendiamide and spirotetramat, and of Thionex 350 EC (active compound endosulfan) were measured for embryo-larval and juvenile stages of the African catfish Clarias gariepinus to assess risks of pesticide use in the cotton basin in Benin (West Africa). For embryo-larval stages, Tihan was more toxic (LC5048h 20 ppm) than Thionex (LC5048h 56 ppm), and flubendiamide was more toxic (LC5048h 2.0 ppm) than spirotetramat (LC5048h 8.44 ppm). All decreased hatching rates. Tihan and spirotetramat disturbed larval swimming coordination; flubendiamide induced tail cleavage. For juvenile fish, Thionex was more toxic (LC5096h 0.22 ppm) than Tihan (LC5096h 8.8 ppm), and flubendiamide (LC5096h 4.7 ppm) was more toxic than spirotetramat (LC5096h 6.0 ppm). Eggs were more resistant than juvenile fish to all tested pesticides except flubendiamide. Although Thionex was more toxic to juvenile fish, replacing Thionex with Tihan may be undesirable for survival of eggs and larvae. PMID:23334459

Agbohessi, P T; Imorou Toko, I; Houndji, A; Gillardin, V; Mandiki, S N M; Kestemont, P

2013-05-01

48

Toxicity of bauxite manufacturing by-products in sea urchin embryos.  

PubMed

By-products from a bauxite manufacturing plant located in Seydi?ehir, Turkey, were investigated for their composition and any toxicity to sea urchin embryogenesis. Samples from three other bauxite plants located in France, Greece, and Italy were simultaneously tested for toxicity in sea urchin embryos. Samples included sludge and solid residues in the plant and sediment and water columns from two holding ponds (red sludge or cryolite residues). Samples were analyzed for their inorganic content by inductively coupled plasma optical emission spectroscopy (ICP-OES). Analyses were carried out either following strong acid extraction or after release of soluble components from seawater-suspended pellets. Toxicity was tested by sea urchin bioassays, to evaluate the following endpoints: (a) acute and/or developmental toxicity, (b) changes in fertilization success, and (c) transmissible damage from sperm to offspring. The results revealed the following: (1) inorganic analysis, following strong acid extraction, showed a prevalence of Al and Fe; (2) seawater release of soluble contaminants was confined to Fe and Mn, whereas Al levels were not changed by suspending increasing sample amounts in seawater; (3) the most severe toxicity to sea urchin embryos was exerted by a 2% water column from the red sludge holding pond and by soil and sludge collected near the plant reactor; (4) sludge supernatant was the most toxic sample to sperm and offspring. The data showed a prevailing association of free Fe (and possibly Mn) levels with Seydi?ehir sample toxicity. The water column of the red sludge holding pond showed both excess levels of free Al and high pH, thus suggesting a combined effect. The differences in sample toxicity in the Seydi?ehir plant compared with other bauxite manufacturing plants suggest a possible variable toxicity as related to bauxite ore composition and/or manufacturing processes. PMID:11800547

Pagano, Giovanni; Meriç, Süreyya; De Biase, Antonella; laccarino, Mario; Petruzzelli, Domenico; Tünay, Olcay; Warnau, Michel

2002-01-01

49

Rapid Aquatic Toxicity Assay Utilizing Labeled Thymidine Incorporation in Sea Urchin Embryos.  

National Technical Information Service (NTIS)

Aquatic toxicity was evaluated in the sea urchin embryo (Arbacea punctulata) by the inhibition of tritiated thymidine incorporation after a brief exposure to toxic chemicals. Arbacia is a useful surrogate species for assay: well-studied, easily cultured a...

E. Jackim D. Nacci

1984-01-01

50

Relative embryotoxic potency of p-substituted phenols in the embryonic stem cell test (EST) and comparison to their toxic potency in vivo and in the whole embryo culture (WEC) assay.  

PubMed

The applicability of the embryonic stem cell test (EST) as an alternative for in vivo embryotoxicity testing was evaluated for a series of five p-substituted phenols. To this purpose, the potency ranking for this class of compounds derived from the inhibition of cardiomyocyte differentiation in the EST was compared to in vivo embryotoxic potency data obtained from literature and to the potency ranking defined in the in vitro whole embryo culture (WEC) assay. From the results obtained it appears that the EST was able to identify the embryotoxic potential for p-substituted phenols, providing an identical potency ranking compared to the WEC assay. However, the EST was not able to predict an accurate ranking for the phenols compared to their potency observed in vivo. Only phenol, the least potent compound within this series, was correctly ranked. Furthermore, p-mercaptophenol was correctly identified as a relative potent congener of the phenols tested, but its ranking was distorted by p-heptyloxyphenol, of which the toxicity was overestimated in the EST. It is concluded that when attempting to explain the observed disparity in potency rankings between in vitro and in vivo embryotoxicity, the in vitro models should be combined with a kinetic model describing in vivo absorption, distribution, metabolism and excretion processes of the compounds. PMID:22820428

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

2012-09-01

51

Embryo Toxic Effects of Depleted Uranium on the Morphology of the Mouse Fetus  

PubMed Central

Although the biokinetics, metabolism, and chemical toxicity of uranium are well known, until recently little attention was paid to the potential toxic effects of uranium on reproduction and development in mammals. In recent years, it has been shown that uranium is a developmental toxicant when given orally or subcutaneously (SC) to mice. Decreased fertility, embryo/fetal toxicity including teratogenicity, and reduced growth of the offspring have been observed following uranium exposure at different gestation periods. For investigating the effects of DU on pregnant animals, three groups (control, sham and test) of NMRI mice were chosen. In test group 4 mg/Kg of DU were administered intraperitonealy at 11 day of gestation, in sham group only normal saline injected to interior peritoneum as indicated in the test group and in Control group which was considered as the comparison base line of our research, no injection was made. Caesarean sections were performed at 15 day of the gestation; and their placentas were examined externally. Base on our results DU caused significant external anomalies, and caused a significant decrease (p < 0.05) in the weight and diameter of placentas, the number of the embryos, their body weight and crown-rump length of fetuses.

Mirderikvand, Nina; Mohammadzadeh Asl, Baharak; Naserzadeh, Parvaneh; Shaki, Fatemeh; Shokrzadeh, Mohammad; Pourahmad, Jalal

2014-01-01

52

Toxicity of crude oil chemically dispersed in a wave tank to embryos of Atlantic herring (Clupea harengus).  

PubMed

Tests of crude oil toxicity to fish are often chronic, exposing embryos from fertilization to hatch to oil solutions prepared using standard mixing procedures. However, during oil spills, fish are not often exposed for long periods and the dynamic nature of the ocean is not easily replicated in the lab. Our objective was to determine if brief exposures of Atlantic herring (Clupea harengus) embryos to dispersed oil prepared by standard mixing procedures was as toxic as oil dispersed in a more realistic model system. Embryos were first exposed to chemically dispersed Alaska North Slope crude and Arabian light crude oil for 2.4 h to 14 d from fertilization to determine if exposure time affected toxicity. Toxicity increased with exposure time, but 2.4-h exposures at realistic concentrations of oil induced blue-sac disease and reduced the percentage of normal embryos at hatch; there was little difference in toxicity between the two oils. Secondly, oil was chemically dispersed in a wave tank to determine if the resultant oil solutions were as toxic to herring embryos as laboratory-derived dispersed oil using a single exposure period of 24 h. Samples taken 15 min postdispersion were more toxic than laboratory-prepared solutions, but samples taken at 5, 30, and 60 min postdispersion were less toxic. Overall, the laboratory- and wave tank-derived solutions of dispersed oil provided similar estimates of toxicity despite differences in the methods for preparing test solutions, suggesting that laboratory and wave tank data are a reliable basis for ecological risk assessments of spilled oil. PMID:22488782

Greer, Colleen D; Hodson, Peter V; Li, Zhengkai; King, Thomas; Lee, Kenneth

2012-06-01

53

The toxicity of heavy metals to embryos of the American oyster Crassostrea virginica  

Microsoft Academic Search

The acute toxicity of 11 heavy metals to embryos of the American oyster Crassostrea virginica was studied and the concentrations at which 50% of the embryos did not develop were determined. The most toxic metals and their LC50 values were mercury (0.0056 ppm), silver (0.0058 ppm), copper (0.103 ppm) and zinc (0.31 ppm). Those metals that were not as toxic

A. Calabrese; R. S. Collier; D. A. Nelson; J. R. MacInnes

1973-01-01

54

Toxicity of different-sized copper nano- and submicron particles and their shed copper ions to zebrafish embryos.  

PubMed

Three sizes of copper nanoparticles (Cu NPs; 25?nm, 50?nm, and 100?nm), 1 submicron-sized particle, and Cu(NO3 )2 were added to the culture buffer of zebrafish embryos from 24?h postfertilization to 120?h postfertilization. In suspensions of Cu NPs and the Cu submicron-sized particle, the main contribution to the toxicity to zebrafish embryos was from the particle form of Cu particles (Cu NPparticle , >71%) rather than from dissolved Cu from the Cu particles (Cu NPion ). All particles tested as well as copper nitrate inhibited hatching, altered behavioral responses, and increased the incidence of malformations. Different kinds of abnormalities were observed in the morphology and behavior of the zebrafish embryos, depending on the particle size of the Cu suspensions tested. The median lethal concentrations of Cu NPparticle (25?nm, 50?nm, and 100?nm), the submicron-sized particle, and copper nitrate were 0.58?mg/L, 1.65?mg/L, 1.90?mg/L, 0.35?mg/L, and 0.70?mg/L, respectively. Submicron-sized particles and copper nitrate were more toxic than Cu NPs, and smaller Cu NPs were more toxic than larger Cu NPs. Dissolution of Cu NPs and the subsequent ion toxicity was not the primary mechanism of Cu NP toxicity in zebrafish embryos. Environ Toxicol Chem 2014;33:1774-1782. © 2014 SETAC. PMID:24839162

Hua, Jing; Vijver, Martina G; Ahmad, Farooq; Richardson, Michael K; Peijnenburg, Willie J G M

2014-08-01

55

Adenovirus gene transfer vector toxicity to mouse embryos: implications for human IVF  

Microsoft Academic Search

BACKGROUND: The promulgation and diversification of micromanipulation procedures which open the zona pellucida of the oocyte or early embryo is steadily increasing the chance that zygotes will encounter infectious viral agents or gene transfer vectors derived from these agents. Such interactions could lead to toxic effects on the embryo or to insertion of foreign genes into the germ line. Adenovirus

Jon W. Gordon

2002-01-01

56

Human endometrial cell coculture reduces the endocrine disruptor toxicity on mouse embryo development  

PubMed Central

Backgrounds Previous studies suggested that endocrine disruptors (ED) are toxic on preimplantation embryos and inhibit development of embryos in vitro culture. However, information about the toxicity of endocrine disruptors on preimplantation development of embryo in human reproductive environment is lacking. Methods Bisphenol A (BPA) and Aroclor 1254 (polychlorinated biphenyls) were used as endocrine disruptors in this study. Mouse 2-cell embryos were cultured in medium alone or vehicle or co-cultured with human endometrial epithelial layers in increasing ED concentrations. Results At 72 hours the percentage of normal blastocyst were decreased by ED in a dose-dependent manner while the co-culture system significantly enhanced the rate and reduced the toxicity of endocrine disruptors on the embryonic development in vitro. Conclusions In conclusion, although EDs have the toxic effect on embryo development, the co-culture with human endometrial cell reduced the preimplantation embryo from it thereby making human reproductive environment protective to preimplantation embryo from the toxicity of endocrine disruptors.

2012-01-01

57

Developmental toxicity and alteration of gene expression in zebrafish embryos exposed to PFOS  

Microsoft Academic Search

Perfluorooctanesulfonate (PFOS) is a persistent organic pollutant, the potential toxicity of which is causing great concern. In the present study, we employed zebrafish embryos to investigate the developmental toxicity of this compound. Four-hour post-fertilization (hpf) zebrafish embryos were exposed to 0.1, 0.5, 1, 3 and 5 mg\\/L PFOS. Hatching was delayed and hatching rates as well as larval survivorship were significantly

Xiongjie Shi; Yongbing Du; Paul K. S. Lam; Rudolf S. S. Wu; Bingsheng Zhou

2008-01-01

58

Toxicity of Buprofezin on the Survival of Embryo and Larvae of African Catfish, Clarias gariepinus (Bloch)  

PubMed Central

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatment for all the concentrations. The mortality of embryos was significantly increased with increasing buprofezin concentrations from 5 to 100 mg/L (p< 0.05). However, the mortality was not significantly different (p<0.05) among the following concentrations: 0 (control), 0.05, 0.5 and 5 mg/L. Data obtained from the buprofezin acute toxicity tests were evaluated using probit analysis. The 24 h LC50 value (with 95% confidence limits) of buprofezin for embryos was estimated to be 6.725 (3.167-15.017) mg/L. The hatching of fish embryos was recorded as 68.8, 68.9, 66.9, 66.4, 26.9, 25.1 and 0.12% in response to 7 different concentrations of buprofezin, respectively. The mortality rate of larvae significantly (p<0.05) increased with increasing buprofezin concentrations exposed to 24-48 h. The 24 and 48 h LC50 values (with 95% confidence limits) of buprofezin for the larvae was estimated to be 5.702 (3.198-8.898) and 4.642 (3.264-6.287) mg/L respectively. There were no significant differences (p>0.05) in the LC50 values obtained at 24 and 48 h exposure times. Malformations were observed when the embryos and larvae exposed to more than 5 mg/L. The results emerged from the study suggest that even the low concentration (5 mg/L) of buprofezin in the aquatic environment may have adverse effect on the early embryonic and larval development of African catfish.

Marimuthu, Kasi; Muthu, Narmataa; Xavier, Rathinam; Arockiaraj, Jesu; Rahman, M. Aminur; Subramaniam, Sreeramanan

2013-01-01

59

Toxicity of buprofezin on the survival of embryo and larvae of African catfish, Clarias gariepinus (Bloch).  

PubMed

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatment for all the concentrations. The mortality of embryos was significantly increased with increasing buprofezin concentrations from 5 to 100 mg/L (p< 0.05). However, the mortality was not significantly different (p<0.05) among the following concentrations: 0 (control), 0.05, 0.5 and 5 mg/L. Data obtained from the buprofezin acute toxicity tests were evaluated using probit analysis. The 24 h LC50 value (with 95% confidence limits) of buprofezin for embryos was estimated to be 6.725 (3.167-15.017) mg/L. The hatching of fish embryos was recorded as 68.8, 68.9, 66.9, 66.4, 26.9, 25.1 and 0.12% in response to 7 different concentrations of buprofezin, respectively. The mortality rate of larvae significantly (p<0.05) increased with increasing buprofezin concentrations exposed to 24-48 h. The 24 and 48 h LC50 values (with 95% confidence limits) of buprofezin for the larvae was estimated to be 5.702 (3.198-8.898) and 4.642 (3.264-6.287) mg/L respectively. There were no significant differences (p>0.05) in the LC50 values obtained at 24 and 48 h exposure times. Malformations were observed when the embryos and larvae exposed to more than 5 mg/L. The results emerged from the study suggest that even the low concentration (5 mg/L) of buprofezin in the aquatic environment may have adverse effect on the early embryonic and larval development of African catfish. PMID:24098390

Marimuthu, Kasi; Muthu, Narmataa; Xavier, Rathinam; Arockiaraj, Jesu; Rahman, M Aminur; Subramaniam, Sreeramanan

2013-01-01

60

Maternal toxicity: a possible etiological factor in embryo-fetal deaths and fetal malformations of rodent-rabbit species.  

PubMed

Data from animal teratology studies were surveyed to determine whether embryo-fetal mortality and fetal malformations result from a primary action of the agent on the conceptus or if they are secondary to maternal toxicity--a consequence of administration with high dose levels of test chemicals. A fairly strong association between embryo-fetal mortality and maternal toxicity was revealed by analysis of data from hamsters, mice, rats, and rabbits in 234 studies of chemical and physical agents, of which 83 were conducted at both maternotoxic and nonmaternotoxic doses, 94 only at maternotoxic doses, and 49 at nonmaternotoxic doses. In the above studies, only nine chemicals (four each in hamsters and rabbits and one in rats) were reported to induce embryo-fetal deaths at apparently nonmaternotoxic doses. These findings tend to suggest a contributory role for maternal toxicity in the induction of embryo-fetal deaths. The previously reported hypothesis that certain fetal defects in mice may perhaps be caused by maternal toxicity was also found to be true in a review of data on hamsters, rats, and rabbits. Salient maternal toxicity-associated fetal malformations were exencephaly, encephalocele, micro- or anophalmia, and fused ribs in hamsters and defective (fused, missing, or extra) ribs, vertebrae, and sternebrae, ex-, an-, or microphthalmia, and cleft palate in rats and rabbits. These malformations occurred at low frequencies, generally with no readily apparent dose-response relationship. Presumptive evidence indicates that embryo-fetal deaths, and the above-mentioned fetal malformations in experimental animals, which in published literature are presently attributed to chemical induction for a large number of chemicals, may be a consequence of maternal toxicity per se. PMID:3983854

Khera, K S

1985-02-01

61

Effects of environmental toxicants on development of a teleost embryo  

SciTech Connect

Embryos of the teleost Fundulus heteroclitus are shown to be useful model systems for monitoring the effects of xenobiotic compounds on development. Fourteen different substances were tested: malathion, aroclor, aldrin, diquat, parathion, pentachlorophenol, sevin, toxaphene, lindane, 2,4-D, DDT, paraquat, 2,4,5-T, and aminotriazole. Concentrations used for each of these was from 0.01 to 10.0 ppm in the incubation dishes. The variety of effects on development observed depended on the compound and its concentration. These effects included inhibition of gastrulation, abnormal axis formation, diminished pigmentation, slowed rate of development, reduced frequency of hatching, loss of neuromuscular control, and reduction or inhibition of heart beat. Possible modes of action of some of these compounds are discussed. It is also shown that embryogenesis is not always the most susceptible part of the organism's life cycle.

Crawford, R.B.; Guarino, A.M.

1985-11-01

62

Photo-induced toxicity of four polycyclic aromatic hydrocarbons (PAHs) to embryos and larvae of the carpet shell clam Ruditapes decussatus.  

PubMed

In this work, we assessed the photo-toxicity of four polycyclic aromatic hydrocarbons (PAHs) to embryos and larvae of the European clam Ruditapes decussatus. The exposure of R. decussatus embryos (24 h) and larvae (96 h) to anthracene, fluoranthene, pyrene and benzo[a]pyrene resulted in reduction of normal D-veliger percentages and high larval mortality, both in darkness and under sunlight conditions. Based on the calculated EC(50) and LC(50) values, the toxicity of the forementioned PAHs was respectively enhanced 72, 35, 60 and 23 times in the embryotoxicity test and 32, 31, 12 and 61 times in the larval mortality test when exposures were performed under sunlight conditions. Simultaneous exposure to sunlight and these PAHs enhanced their toxicity in comparison to dark conditions. The clam embryos and larvae appear to be environmentally relevant life-stages in assessing the toxic and photo-toxic risk of PAHs that enter the marine environment. PMID:22446967

Fathallah, Salem; Medhioub, Mohamed Néjib; Kraiem, Mohamed Mejdeddine

2012-06-01

63

The VIRTUAL EMBRYO. A Computational Framework for Developmental Toxicity  

EPA Science Inventory

EPA?s ?Virtual Embryo Project? (v-Embryo?) is focused on the predictive toxicology of children?s health and developmental defects following prenatal exposure to environmental chemicals. The research is motivated by scientific principles in systems biology as a framework for the g...

64

Effects of storage temperature and duration on toxicity of sediments assessed by Crassostrea gigas oyster embryo bioassay  

SciTech Connect

The effects of temperature and duration of storage on the toxicity of estuarine sediments were investigated with the Crassostrea gigas oyster embryo bioassay. Sediments ranging from unpolluted (controls) to extremely polluted with heavy metals (>100 ppm Hg, Cu, Zn, and Pb) and total hydrocarbons (>1,000 ppm) were collected from sites in southwest France and northern Spain, Control sediments were toxic only at the highest concentrations tested and after freezing in liquid nitrogen ({minus}196 C). Polluted sediments significantly reduced the success of oyster embryogenesis. Analysis of variance showed that the effect of storage temperature on toxicity increased with the prolongation of storage. Prolonged storage of fresh (4 C) sediments resulted in a loss of toxicity, which was more rapid in the less-polluted sediments. Deep-frozen sediments ({minus}196 C) were highly toxic regardless of origin and storage time, and because deep-freezing causes spurious toxicity in the control samples, it cannot be recommended for toxicological studies. In the context of the assessment of sediment toxicity by embryo-larval bioassays, fresh (4 C) storage is recommended when sediments need to be stored for no longer than a few days. The advisable duration of fresh storage to avoid false-negative results is directly related to the degree of toxicity. Should the sediments require prolonged storage, freezing at {minus}20 C appears to be the best choice.

Beiras, R. [Univ. de Vigo, Galicia (Spain). Area de Ecoloxia; His, E. [IFREMER Station d`Arcachon (France). Quai Silohuette; Seaman, M.N.L. [Inst. of Marine Research, Kiel (Germany). Fisheries Biology Dept.

1998-10-01

65

Developmental toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in artificially fertilized crucian carp (Carassius auratus) embryo.  

PubMed

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent bioaccumulative environmental contaminant that is an endocrine disruptor. Embryos of various fish species are responsive to TCDD and have been used as an alternative method to the acute toxicity test with juvenile and adult fish. The TCDD test has similar endpoints of developmental toxicity. However, their sensitivity and signs of TCDD-induced toxicity are different depending on fish species and its habit. Crucian carp (Carassius auratus) - the sentinel species for persistent organic pollutants and a common foodfish in China, Japan, and Korea - was used to identify the developmental toxicity of TCDD. We obtained the fertilized eggs from the artificial fertilization of crucian carp (97.45% success rate). Embryos at 3h post fertilization (hpf) were exposed to no vehicle, vehicle (dimethylsulfoxide, 0.1% v/v) or TCDD (0.128, 0.32, 0.8, 2 and 5?g/L) for 1h and then fresh water was changed and aerated. Embryonic development and toxicity were monitored until 150 hpf. TCDD-exposed group showed no effects on embryo mortality and hatching rate from 6 to 126 hpf. On the other hand, the post-hatching mortality rate in TCDD-exposed group was increased in a dose-dependent manner, especially at high doses (0.8, 2 and 5?g/L). The LD50 for larval mortality was calculated to 0.24ngTCDD/g embryo. Pericardial edema was continuously observed in larvae of TCDD-exposed groups from hatching complete time (78 hpf), followed by the onset of yolk sac edema. Hemorrhage and edema showed a significant increase depending on exposure concentration and time. Expression of TCDD-related CYP1A genes was evaluated quantitatively. Embryo and larvae in TCDD-exposed groups displayed a significant increase of CYP1A gene expression. Overall, we defined TCDD-induced toxicity in artificially fertilized crucian carp embryo and these results suggest that crucian carp can be applied as an early life stage model of TCDD-induced toxicity. PMID:24751158

Park, Yong Joo; Lee, Min Jee; Kim, Ha Ryong; Chung, Kyu Hyuck; Oh, Seung Min

2014-09-01

66

vEmbryo In Silico Models: Predicting Vascular Developmental Toxicity  

EPA Science Inventory

The cardiovascular system is the first to function in the vertebrate embryo, reflecting the critical need for nutrient delivery and waste removal during organogenesis. Blood vessel development occurs by complex interacting signaling networks, including extra-cellular matrix remod...

67

AQUATIC ANIMALS IN TOXICITY TESTING  

EPA Science Inventory

Aquatic animals serve as useful models for toxicological evaluations that bridge the gap between real world and laboratory problems. Selected aquatic organisms are adaptable to laboratory experimentation in areas such as toxicity testing and chronic sublethal risks evaluation inc...

68

Proteomic Signatures of the Zebrafish (Danio rerio) Embryo: Sensitivity and Specificity in Toxicity Assessment of Chemicals  

PubMed Central

Studies using embryos of the zebrafish Danio rerio (DarT) instead of adult fish for characterising the (eco-) toxic potential of chemicals have been proposed as animal replacing methods. Effect analysis at the molecular level might enhance sensitivity, specificity, and predictive value of the embryonal studies. The present paper aimed to test the potential of toxicoproteomics with zebrafish eleutheroembryos for sensitive and specific toxicity assessment. 2-DE-based toxicoproteomics was performed applying low-dose (EC10) exposure for 48?h with three-model substances Rotenone, 4,6-dinitro-o-cresol (DNOC) and Diclofenac. By multivariate “pattern-only” PCA and univariate statistical analyses, alterations in the embryonal proteome were detectable in nonetheless visibly intact organisms and treatment with the three substances was distinguishable at the molecular level. Toxicoproteomics enabled the enhancement of sensitivity and specificity of the embryonal toxicity assay and bear the potency to identify protein markers serving as general stress markers and early diagnosis of toxic stress.

Hanisch, Karen; Kuster, Eberhard; Altenburger, Rolf; Gundel, Ulrike

2010-01-01

69

Toxicity of weathered coal tar for shortnose sturgeon (Acipenser brevirostrum) embryos and larvae.  

PubMed

Weathered coal tar collected from the Connecticut River near Holyoke, Massachusetts, was toxic to shortnose sturgeon embryos and larvae in whole sediment flow-through and elutriate static-renewal laboratory exposures. Sterile laboratory sand and clean Connecticut River sand, collected upstream from the coal tar deposits, produced no significant difference in toxicity to sturgeon embryos-larvae, while coal tar-contaminated sediment produced over 95% embryo-larval mortality. Hydrocarbon transfer and subsequent toxicity appeared to be via direct contact of the embryos with contaminated sediment, rather than via exposure to soluble hydrocarbons. This conclusion was supported by exposure of embryos and larvae to elutriates (e.g., water soluble extract) of coal-tar sediments, that resulted in embryo and larval mortality at low molecular weight PAH concentrations-0.47 mg/L, higher than would occur naturally. No decrease in petroleum hydrocarbon concentration was observed in sediments exposed to flowing water for 14 d, supporting the contention that soluble hydrocarbons were not responsible for the observed toxicity in whole sediment exposures under the conditions employed in this study. PMID:8785011

Kocan, R M; Matta, M B; Salazar, S M

1996-08-01

70

Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality.  

PubMed

The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions. PMID:23601886

Khosrovyan, A; Rodríguez-Romero, A; Salamanca, M J; Del Valls, T A; Riba, I; Serrano, F

2013-05-15

71

Comparison of the toxicity of silver, gold and platinum nanoparticles in developing zebrafish embryos.  

PubMed

Nanoparticles have diverse applications in electronics, medical devices, therapeutic agents and cosmetics. While the commercialization of nanoparticles is rapidly expanding, their health and environmental impact is not well understood. Toxicity assays of silver, gold, and platinum nanoparticles, using zebrafish embryos to study their developmental effects were carried out. Gold (Au-NP, 15-35 nm), silver (Ag-NP, 5-35 nm) and platinum nanoparticles (Pt-NP, 3-10 nm) were synthesized using polyvinyl alcohol (PVA) as a capping agent. Toxicity was recorded in terms of mortality, hatching delay, phenotypic defects and metal accumulation. The addition of Ag-NP resulted in a concentration-dependant increase in mortality rate. Both Ag-NP and Pt-NP induced hatching delays, as well as a concentration dependant drop in heart rate, touch response and axis curvatures. Ag-NP also induced other significant phenotypic changes including pericardial effusion, abnormal cardiac morphology, circulatory defects and absence or malformation of the eyes. In contrast, Au-NP did not show any indication of toxicity. Uptake and accumulation of nanoparticles in embryos was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES), which revealed detectable levels in embryos within 72 hpf. Ag-NP and Au-NP were taken up by the embryos in relatively equal amounts whereas lower Pt concentrations were observed in embryos exposed to Pt-NP. This was probably due to the small size of the Pt nanoparticles compared to Ag-NP and Au-NP, thus resulting in fewer metal atoms being retained in the embryos. Among the nanoparticles studied, Ag-NPs were found to be the most toxic and Au-NPs the non-toxic. The toxic effects exhibited by the zebrafish embryos as a consequence of nanoparticle exposure, accompanied by the accumulation of metals inside the body calls for urgent further investigations in this field. PMID:21417687

Asharani, P V; Lianwu, Yi; Gong, Zhiyuan; Valiyaveettil, Suresh

2011-03-01

72

Protective effects of antioxidant vitamins on Aroclor 1254-induced toxicity in cultured chicken embryo hepatocytes  

Microsoft Academic Search

Primary culture of chicken embryo hepatocytes (CEHs) was established to reveal toxicity of polychlorinated biphenyls (PCBs) and attenuating effects of antioxidants vitamin E (VE), vitamin C (VC) and vitamin A (VA) on PCBs-induced cytotoxicity. CEHs were dispersed from 14-day-old chicken embryo livers and exposed to Aroclor 1254 (A1254) in the range of 0.1–10?g\\/ml, A1254 (10?g\\/ml) and each vitamin (10?g\\/ml) for

Caiqin Zhou; Caiqiao Zhang

2005-01-01

73

USING THE MEDAKA EMBRYO ASSAY TO INVESTIGATE DEVELOPMENTAL ETHANOL TOXICITY.  

EPA Science Inventory

Ethanol (EtOH) is a well-known developmental toxicant that produces a range of abnormal phenotypes. While the toxic potential of developmental EtOH exposure is well characterized, the effect of the timing of exposure on the extent of toxicity remains unknown. Fish models such as ...

74

Evaluation of Bleached Kraft Mill Process Water Using Microtox®, Ceriodaphnia dubia, and Menidia beryllina Toxicity Tests  

Microsoft Academic Search

.   To determine whether a 7- to 10-d embryo toxicity\\/teratogenicity test with the inland silverside fish, Menidia beryllina, is a sensitive indicator for evaluation of bleached kraft mill effluents, we compared this test with the Microtox® 15-min\\u000a acute toxicity test and the Ceriodaphnia dubia 7-d chronic toxicity test. Water samples used in each test were collected from three areas in

D. P. Middaugh; N. Beckham; J. W. Fournie; T. L. Deardorff

1997-01-01

75

Primary Screening of the Bioactivity of Brackishwater Cyanobacteria: Toxicity of Crude Extracts to Artemia salina Larvae and Paracentrotus lividus Embryos  

PubMed Central

Cyanobacteria are a diverse group of Gram-negative bacteria that produce an array of secondary compounds with selective bioactivity against vertebrates, invertebrates, plants, microalgae, fungi, bacteria, viruses and cell lines. The aim of this study was to assess the toxic effects of aqueous, methanolic and hexane crude extracts of benthic and picoplanktonic cyanobacteria isolated from estuarine environments, towards the nauplii of the brine shrimp Artemia salina and embryos of the sea urchin Paracentrotus lividus. The A. salina lethality test was used as a frontline screen and then complemented by the more specific sea urchin embryo-larval assay. Eighteen cyanobacterial isolates, belonging to the genera Cyanobium, Leptolyngbya, Microcoleus, Phormidium, Nodularia, Nostoc and Synechocystis, were tested. Aqueous extracts of cyanobacteria strains showed potent toxicity against A. salina, whereas in P. lividus, methanolic and aqueous extracts showed embryo toxicity, with clear effects on development during early stages. The results suggest that the brackishwater cyanobacteria are producers of bioactive compounds with toxicological effects that may interfere with the dynamics of invertebrate populations.

Lopes, Viviana R.; Fernandez, Nuria; Martins, Rosario F.; Vasconcelos, Vitor

2010-01-01

76

Effects of simulated weathering on the toxicity of selected crude oils and their components to sea urchin embryos.  

PubMed

Artificial weathering of Angolan crude and a Heavy Fuel Oil (HFO) was performed by evaporation and photooxidation. The aliphatic, aromatic, polar and asphaltene fractions of the fresh and weathered oils were isolated. The toxicity of the water accommodated fraction or an oil/fraction dissolved in DMSO was assessed using the sea urchin embryo test. Photooxidation was observed to decrease the aromatics content and increase polar compounds. A slight reduction in the toxicity of Angolan crude was observed following weathering for the water-accommodated fraction and the extract in DMSO, but no effect was seen for the Heavy Fuel Oil. For aliphatic compounds, the toxicity decreased in the order fresh>evaporated>photooxidated for both Angolan crude and HFO. Weathering slightly increased the toxicity of the aromatic and polar fractions of the oil. The aromatic fractions were responsible for most of the toxicity and the polar compounds were the second most important toxic components, despite having less or similar abundance than the aliphatic fraction. The toxic contribution of the aromatic compounds was higher for the HFO than for the Angolan crude. A decrease in the toxicity of Angolan crude following weathering correlated with a reduction in the toxicity of the aliphatic fraction. PMID:23747464

Rial, Diego; Radovi?, Jagoš R; Bayona, Josep M; Macrae, Kenneth; Thomas, Kevin V; Beiras, Ricardo

2013-09-15

77

Early life stage and genetic toxicity of stannous chloride on zebrafish embryos and adults: toxic effects of tin on zebrafish.  

PubMed

Humans are exposed to stannous chloride (SnCl(2)), known as tin chloride, present in packaged food, soft drinks, biocides, dentifrices, etc. Health effects in children exposed to tin and tin compounds have not been investigated yet. Therefore, we evaluated the possible teratogenic effects and genotoxic of SnCl(2) in zebrafish (Danio rerio) adults and their embryos. In the embryo-larval study, SnCl(2) showed embryo toxicity and developmental delay after exposure to the various concentrations of 10-250 ?M for 120 h. Teratogenic effects including morphological malformations of the embryos and larvae were observed. The embryos exposed to 100 ?M displayed tail deformation at 28 hpf and the larvae exposed to 50 ?M showed reduced body growth, smaller head and eyes, bent trunk, mild pericardial edema, and smaller caudal fin at 96 hpf. The results of the teratological study show that SnCl(2) induced a significant decrease in the number of living embryos and larvae. Regarding the chromosome analysis, SnCl(2) induced a dose-dependent increase in the micronucleus (MN) frequency in peripheral erythrocytes of adult zebrafish. In blood cells, the 25 ?M dose of SnCl(2) caused a nonsignificant increase in the total chromosomal aberrations, but the high doses significantly increased the total number of chromosomal aberrations compared with the control groups. Overall, the results clearly indicate that SnCl(2) is teratogenic and genotoxic to zebrafish. PMID:20014007

?i?man, Turgay

2011-06-01

78

METAL TOXICITY TO EMBRYOS AND LARVAE OF EIGHT SPECIES OF FRESHWATER FISH--II: COPPER  

EPA Science Inventory

Fish larvae and early juveniles of all species tested (brook trout, rainbow trout, brown trout, lake trout, northern pike, white sucker, herring and smallmouth bass) were more sensitive to copper than the embryos. Embryo survival was affected only at the higher concentrations tes...

79

Influence of storage methods, refrigeration or freezing, on the toxicity of wastewater samples to oyster embryos.  

PubMed

One of the main concerns in wastewater whole effluent assessment is the sampling phase and the sample chain of custody before any toxicity evaluation. The major problem is related to establishing the correct method for sample storage in order to perform toxicity bioassays. The toxicity of some domestic and glass factory industrial wastewater samples stored both by refrigeration at 4 +/- 1 degrees C for no more than three days, and freezing at -18 +/- 1 degrees C for no more than one month was compared via the embryo larval development bioassay with the oyster Crassostrea gigas. The results showed no significant differences between the toxicities of refrigerated and frozen wastewater samples. The wastewater classification, according to a score based on four toxicity classes, showed that the preservation methods did not alter the toxicity classification of the samples. In particular, it was demonstrated that the samples considered as 'not acutely toxic' after refrigeration were also found to have this classification after freezing. PMID:19603701

Libralato, G; Avezzù, F; Losso, C; Volpi Ghirardini, A

2009-05-01

80

Acute Toxicity, Uptake and Histopathology of Aqueous Methyl Mercury to Fathead Minnow Embryos  

Microsoft Academic Search

Early life stages of fishes have been shown to be especially susceptible to the toxic effects of heavy metal pollution. In\\u000a this study, fathead minnow (Pimephales promelas) embryos were exposed in the laboratory to a graded series of aqueous methyl mercury concentrations under continuous-flow\\u000a conditions. A number of toxicological endpoints were examined including; acute toxicity, bioaccumulation, protein production,\\u000a impact on

Edward W. Devlin

2006-01-01

81

The toxicity of silver nanoparticles to zebrafish embryos increases through sewage treatment processes.  

PubMed

Silver nanoparticles (AgNPs) are widely believed to be retained in the sewage sludge during sewage treatment. The AgNPs and their derivatives, however, re-enter the environment with the sludge and via the effluent. AgNP were shown to occur in surface water, while evidence of a potential toxicity of AgNPs in aquatic organisms is growing. This study aims to examine the toxicity of AgNPs to the embryos of the aquatic vertebrate model zebrafish (Danio rerio) before and after sewage treatment plants (STPs) processes. Embryos were treated with AgNP (particle size: >90 % <20 nm) and AgNO3 in ISO water for 48 h and consequently displayed effects such as delayed development, tail malformations and edema. For AgNP, the embryos were smaller than the controls with conspicuously smaller yolk sacs. The corresponding EC50 values of 48 hours post fertilization (hpf) were determined as 73 ?g/l for AgNO3 and 1.1 mg/l for AgNP. Whole-mount immunostainings of primary and secondary motor neurons also revealed secondary neurotoxic effects. A TEM analysis confirmed uptake of the AgNPs, and the distribution within the embryo suggested absorption across the skin. Embryos were also exposed (for 48 h) to effluents of AgNP-spiked model STP with AgNP influent concentrations of 4 and 16 mg/l. These embryos exhibited the same malformations than for AgNO3 and AgNPs, but the embryo toxicity of the sewage treatment effluent was higher (EC50 = 142 ?g/l; 48 hpf). On the other hand, control STP effluent spiked with AgNPs afterwards was less toxic (EC50 = 2.9 mg/l; 48 hpf) than AgNPs in ISO water. This observation of an increased fish embryo toxicity of STP effluents with increasing AgNP influent concentrations identifies the accumulation of AgNP in the STP as a potential source of effluent toxicity. PMID:23975539

Muth-Köhne, Elke; Sonnack, Laura; Schlich, Karsten; Hischen, Florian; Baumgartner, Werner; Hund-Rinke, Kerstin; Schäfers, Christoph; Fenske, Martina

2013-10-01

82

Toxic trace metals and embryo quality indicators during in vitro fertilization (IVF)  

Microsoft Academic Search

Trace exposures to the toxic metals mercury (Hg), cadmium (Cd) and lead (Pb) may interfere with in vitro fertilization (IVF). The aim of this study is to explore biologically plausible hypotheses concerning associations between metals and embryo quality indicators during IVF. For 24 female patients, a multivariable ordinal logistic regression model suggests a 75% reduction in the odds for higher

Michael S. Bloom; Patrick J. Parsons; Dongsul Kim; Amy J. Steuerwald; Sergio Vaccari; Gloria Cheng; Victor Y. Fujimoto

2011-01-01

83

Assessing contamination levels of amprolium and tylosin using the embryo toxicity assay and three biomarkers  

Microsoft Academic Search

This study was conducted to examine the adverse biological effects of two veterinary pharmaceuticals (Amprolium and tylosin) on aquatic organisms. The zebrafish embryo toxicity assays were performed in combination with three biomarkers, including superoxide dismutase (SOD), lipid peroxidation (LPO) and heat shock protein 70(Hsp70). The LPO extent was expressed by malondialdehyde (MDA) in this paper. Logit Loglinear analysis was used

Jun Hu; Yong Liang; Minjie Chen; Xiaorong Wang

2010-01-01

84

Developmental toxicity in rare minnow (Gobiocypris rarus) embryos exposed to Cu, Zn and Cd.  

PubMed

Using rare minnow (Gobiocypris rarus) embryos as experimental model, the developmental toxicity of Cu, Zn and Cd were investigated following exposure to 0.001-1.000mg/L for 72h, and the toxicity effects were evaluated by larval malformation rate, heart rate, pericardial area, spontaneous movements, tail length, enzyme activities and biomarker genes. Our results revealed that increased malformation rate provide a gradual dose-response relationship, and the most pronounced morphological alteration was heart and body malformations. Values of 72h EC50 with their 95 percent confidence intervals on G. rarus embryos were 0.103 (0.072-0.149)mg/L for Cu, 0.531 (0.330-1.060)mg/L for Zn, 0.219 (0.147-0.351)mg/L for Cd. Enzyme activities can be regard as a type of low-dose stimulation and high-dose inhibition. Stress and metabolism-related genes (hsp70, cyp1a and mt) were significantly up-regulated, development-related genes (wnt8a, vezf1 and mstn) were significantly down-regulated after the treatment by Cu, Zn and Cd. Overall, the present study points out Cu, Zn and Cd are highly toxic to G. rarus embryos. The information presented in this study will be helpful in fully understanding the toxicity induced by Cu, Zn and Cd in fish embryos. PMID:24726939

Zhu, Bin; Liu, Lei; Li, Dong-Liang; Ling, Fei; Wang, Gao-Xue

2014-06-01

85

Toxicity and modulations of biomarkers in Xenopus laevis embryos exposed to polycyclic aromatic hydrocarbons and their N-heterocyclic derivatives.  

PubMed

Effects of a newly identified group of organic environmental pollutants of concern (N-heterocyclic derivatives of polycyclic aromatic hydrocarbons, NPAHs) were investigated using the 96 h FETAX (Frog Embryo Teratogenesis Assay - Xenopus). Beside standard FETAX parameters (mortality, malformations), changes in several biochemical markers were studied as early signs of intoxication. Biomarkers included determination of glutathione (GSH) levels and lipid peroxidation as well as activities of important detoxification and antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase, glutathione reductase). 1,10-Phenathroline was the most toxic of all tested compounds (96 h LC(50) = 4 microM). All tested NPAHs induced malformations in the frog embryos. The data suggest that the exposure to NPAHs can induce oxidative stress in amphibians; most biochemical markers were modulated at concentrations lower than those resulting in significant mortality. Results document mortality and teratogenicity of all studied NPAHs to amphibian embryos while no significant mortality, teratogenicity or modulations in biochemical markers could be observed with unsubstituted polycyclic aromatic hydrocarbons (PAHs) at concentrations up to their water solubility. This information along with the significantly greater solubility and thus bioavailability compared to their nonsubstituted parent compounds suggests that NPAHs could contribute significantly to the overall aquatic toxicity of mixtures of PAHs and their derivatives. PMID:17091503

Burýsková, Blanka; Hilscherová, Klára; Bláha, Ludek; Marsálek, Blahoslav; Holoubek, Ivan

2006-12-01

86

Toxicity to medaka fish embryo development of okadaic acid and crude extracts of Prorocentrum dinoflagellates.  

PubMed

Chronic and subchronic toxicity following exposure to the DSP (Diarrhetic shellfish poisoning) toxin okadaic acid (OA) is receiving increasing attention as a public human health biohazard. However information on ecological impacts induced by proliferation of the OA producing dinoflagellate Prorocentrum is scarce. In order to analyse the toxicity of these substances, in vivo experiments were conducted on medaka fish (Oryzias latipes) embryos used as an experimental model. The study was focused on two strains of benthic Prorocentrum species, P. arenarium and P. emarginatum, naturally found in the Indian Ocean. Sample extracts (crude extracts, CE) were obtained from algal cultures and their toxic potential was explored. Their OA (and derivatives) content was evaluated by two methods: one based on chemical analysis using HPLC-MS, the other based on screening the inhibiting effect on protein phosphatase PP2A. P. arenarium extracts inhibit PP2A and the active toxin was confirmed as being OA by HPLC-MS. In contrast, P. emarginatum showed negative results regardless of the method used. The development of medaka fish embryos kept in medium containing pure OA or Prorocentrum CE was examined. Survival rates were reduced up to 100% depending on the concentrations used of both OA and CE of P. arenarium, while no effect was observed with CE of P. emarginatum. Anatomopathological studies of surviving embryos indicate that OA treatment resulted in significant increases in liver and digestive tract areas compared to controls. P. arenarium treated surviving embryos exhibited significant quantitative increases of global body and vitellus areas. Together, our results indicate that the toxic effects to medaka embryos development of pure OA and P. arenarium extracts containing OA are distinguishable. The differences may indicate the presence of additional toxic substance(s) (or molecules able to modulate OA impact) in the P. arenarium CE that probably are not present in P. emarginatum. PMID:17382985

Escoffier, Nicolas; Gaudin, Julien; Mezhoud, Karim; Huet, Hélène; Chateau-Joubert, Sophie; Turquet, Jean; Crespeau, François; Edery, Marc

2007-06-15

87

Influence of the salinity adjustment methods, salts and brine, on the toxicity of wastewater samples to mussel embryos.  

PubMed

One of the main problems of the Whole Effluent Toxicity is related to the use of bioindicator species representative of the target environment. Most wastewater discharges are of fresh water, so their salinity has to be adjusted when they are discharged to transitional and marine coastal waters, in order to perform toxicity bioassays with reliable organisms. At the moment, there is no optimum technique to allow sample salinity to be adjusted and no specific information regarding salinity adjustment when bivalves are being considered for toxicity test performance. This paper provides information on the potential use of different methods to adjust the salinity of hotel/domestic wastewater samples with different brands of natural and synthetic Dry Salts (DS) and HyperSaline Brine (HSB) for use in the embryo larval development bioassay with the mussel Mytilus galloprovincialis. HyperSaline Brine derived from reconstructed artificial seawater proved to be more viable for wastewater salinity adjustment than DS. PMID:19213470

Libralato, G; Losso, C; Avezzù, F; Volpi Ghirardini, A

2009-01-01

88

Linking embryo toxicity with genotoxic responses in the freshwater snail Physa acuta: single exposure to benzo(a)pyrene, fluoxetine, bisphenol A, vinclozolin and exposure to binary mixtures with benzo(a)pyrene.  

PubMed

Genotoxic effects on fauna after waterborne pollutant exposure have been demonstrated by numerous research programmes. Less effort has been focused on establishing relationship between genotoxicity and long-term responses at higher levels of biological organization. Taking into account that embryos may be more sensitive indicators of reproductive impairment than alterations in fertility, we have developed two assays in multiwell plates to address correlations between embryo toxicity and genotoxicity. The potential teratogenicity was assessed by analyzing abnormal development and mortality of Physa acuta at embryonic stage. Genotoxicity was measured by the micronucleus (MN) test using embryonic cells. Our results showed that linkage between genotoxicity and embryo toxicity depends on mechanisms of action of compounds under study. Embryo toxic responses showed a clear dose-related tendency whereas no clear dose-dependent effect was observed in micronucleus induction. The higher embryo toxicity was produced by benzo(a)pyrene exposure followed by fluoxetine and bisphenol A. Vinclozolin was the lower embryo toxic compound. Binary mixtures with BaP always resulted in higher embryo toxicity than single exposures but antagonistic effects were observed for MN induction. Benzo(a)pyrene produced the higher MN induction at 0.04 mg/L, which also produced clear embryo toxic effects. Fluoxetine did not induce cytogenetic effects but 0.25mg/L altered embryonic development. Bisphenol A significantly reduced hatchability at 0.5mg/L while MN induction appeared with higher treatments than those that start causing teratogenicity. Much higher concentration of vinclozolin (5mg/L) reduced hatchability and induced maximum MN formation. In conclusion, while validating one biomarker of genotoxicity and employing one ecologically relevant effect, we have evaluated the relative sensitivity of a freshwater mollusc for a range of chemicals. The embryo toxicity test is a starting point for the development of a life cycle test with freshwater snails even for undertaking multigeneration studies focused on transgenerational effects. PMID:22417675

Sánchez-Argüello, Paloma; Aparicio, Natalia; Fernández, Carlos

2012-06-01

89

Toxic effects of triazophos on rare minnow (Gobiocypris rarus) embryos and larvae.  

PubMed

Triazophos (TAP) has been widely used in agriculture for controlling insect pests and is a known organophosphorus pesticide. Due to TAP characteristics, such as high chemical and photochemical stability, its potential toxicity to aquatic organisms has gained great interest. To explore the potential developmental toxicity of TAP, Gobiocypris rarus embryos and larvae were exposed to various concentrations of TAP (0.1-15mgL(-)(1)) until 72h. Results showed that values of 72h LC50 and EC50 were 7.44 and 5.60mgL(-)(1) for embryos, 2.52 and 1.37mgL(-)(1) for larvae. Increased malformation, decreased heart rate and body length provide a gradual concentration-dependent pattern. Enzyme activities and mRNA levels were significantly changed even at low concentration (0.05mgL(-)(1) for embryos and 0.01mgL(-)(1) for larvae). Overall, the present study points out that TAP is likely a risk to the early development of G. rarus. The information presented in this study will be helpful in better understanding the toxicity induced by TAP in fish embryos and larvae. PMID:24875911

Zhu, Bin; Gong, Yu-Xin; Liu, Lei; Li, Dong-Liang; Wang, Yuan; Ling, Fei; Wang, Gao-Xue

2014-08-01

90

Zebrafish (Danio rerio) embryos as a model for testing proteratogens.  

PubMed

Zebrafish embryos have been shown to be a useful model for the detection of direct acting teratogens. This communication presents a protocol for a 3-day in vitro zebrafish embryo teratogenicity assay and describes results obtained for 10 proteratogens: 2-acetylaminofluorene, benzo[a]pyrene, aflatoxin B(1), carbamazepine, phenytoin, trimethadione, cyclophosphamide, ifosfamide, tegafur and thio-TEPA. The selection of the test substances accounts for differences in structure, origin, metabolism and water solubility. Apart from 2-acetylaminofluorene, which mainly produces lethal effects, all proteratogens tested were teratogenic in zebrafish embryos exposed for 3 days. The test substances and/or the substance class produced characteristic patterns of fingerprint endpoints. Several substances produced effects that could be identified already at 1 dpf (days post fertilization), whereas the effects of others could only be identified unambiguously after hatching at ? 3 dpf. The LC?? and EC?? values were used to calculate the teratogenicity index (TI) for the different substances, and the EC?? values were related to human plasma concentrations. Results lead to the conclusion that zebrafish embryos are able to activate proteratogenic substances without addition of an exogenous metabolic activation system. Moreover, the teratogenic effects were observed at concentrations relevant to human exposure data. Along with other findings, our results indicate that zebrafish embryos are a useful alternative method for traditional teratogenicity testing with mammalian species. PMID:21237239

Weigt, Stefan; Huebler, Nicole; Strecker, Ruben; Braunbeck, Thomas; Broschard, Thomas H

2011-03-15

91

Identification of compounds in heavy fuel oil that are chronically toxic to rainbow trout embryos by effects-driven chemical fractionation.  

PubMed

The present study isolated and identified compounds in heavy fuel oil 7102 (HFO 7102) that are bioavailable and chronically toxic to rainbow trout embryos (Oncorhynchus mykiss). An effects-driven chemical fractionation combined the chemical separation of oil with toxicity testing and chemical analyses of each fraction to identify the major classes of compounds associated with embryo toxicity. Toxicity was assessed with 2 exposure methods, a high-energy chemical dispersion of oil in water, which included oil droplets in test solutions, and water accommodated fractions which were produced by oiled gravel desorption columns, and which did not contain visible oil droplets. Fractions of HFO with high concentrations of naphthalenes, alkanes, asphaltenes, and resins were nontoxic to embryos over the range of concentrations tested. In contrast, fractions enriched with 3- to 4-ringed alkyl polycyclic aromatic hydrocarbons (PAHs) were embryotoxic, consistent with published studies of crude oils and individual alkyl PAHs. The rank order of fraction toxicity did not vary between the exposure methods and was consistent with their PAH content; fractions with higher-molecular weight alkyl PAHs were the most toxic. Exposure of juvenile trout to most fractions of HFO induced higher activities of cytochrome P450 enzymes, with a rank order of potency that varied with exposure method and differed somewhat from that of embryotoxicity. Induction reflected the bioavailability of PAHs but did not accurately predict embryotoxicity. PMID:24375932

Adams, Julie; Bornstein, Jason M; Munno, Keenan; Hollebone, Bruce; King, Thomas; Brown, R Stephen; Hodson, Peter V

2014-04-01

92

DEVELOPMENTAL TOXICITY OF METHANOL IN WHOLE EMBRYO CULTURE: A COMPARATIVE STUDY WITH MOUSE AND RAT EMBRYOS  

EPA Science Inventory

Methanol (MeOH), a widely used industrial solvent, had been proposed as an alternative motor vehicle fuel. nhaled MEOH is teratogenic in both rats and mice but the mouse has been demonstrated to be sensitive to the developmental toxicity of inhaled methanol at lower exposures tha...

93

EFFECTS OF DRILLING FLUIDS ON EMBRYO DEVELOPMENT  

EPA Science Inventory

Toxicity of used drilling fluids to embryo development was investigated to ascertain the limits of safe usage of these fluids in marine environments. Embryos used as test systems were of the teleost, Fundulus heteroclitus, and four echinoderms Echinarachnius parma, Strongylocentr...

94

Mechanisms of hexabromocyclododecanes induced developmental toxicity in marine medaka (Oryzias melastigma) embryos.  

PubMed

Hexabromocyclododecanes (HBCDs) are widely used as additive brominated flame retardants, and are now ubiquitous contaminants in the environmental media and biota, including the marine environment and marine organisms. However, the impacts of HBCDs on marine fish are not well known. In this study the embryos of marine medaka (Oryzias melastigma) were used to assess the developmental toxicity of HBCDs. Freshly fertilized marine medaka embryos were exposed to various concentrations of technical HBCD (tHBCD, 0, 5, 20 and 50?g/L) until the first fry stage, and hatch success, morphology and cardiac function were examined. In all the exposure groups (5, 20 and 50?g/L) tHBCD significantly increased the embryo heart beats. The measurement of sinus venosus-bulbus arteriosus (SV-BA) distance indicated that tHBCD significantly enlarged the SV-BA distance at exposure concentrations of 20 and 50?g/L. The malformation rate at the first fry stage was also induced by tHBCD in a dose dependent manner, with the formation of pericardial edema and yolk sac edema as the most frequently observed malformation. In addition, the concentrations of total HBCD isomers (?HBCDs) in embryos in the current study were comparative with environmental levels and increased with increasing exposure duration. Furthermore, exposure to tHBCD also induced the level of 8-oxodG, a representative oxidative DNA damage. The mechanisms of HBCD-induced developmental toxicity were further explored by TUNEL assay, gel-based quantitative proteomic approach and measurement of the expression of several stress responsive genes, such as p53, TNF-?, IL-1?, CYP1A, COX-1 and COX-2, together with the activities of caspases. The results suggested that HBCDs exposure at environmentally realistic concentrations induced oxidative stress and apoptosis, and suppressed nucleotide and protein synthesis, which all together resulted in developmental toxicity, particularly in the cardiovascular system, in the embryos of O. melastigma. PMID:24780359

Hong, Haizheng; Li, Dongmei; Shen, Rong; Wang, Xinhong; Shi, Dalin

2014-07-01

95

Rapid Aquatic Toxicity Assay Using Incorporation of Tritiated-Thymidine into Sea Urchin, 'Arbacia punctulata', Embryo: Evaluation of Toxicant Exposure Procedures.  

National Technical Information Service (NTIS)

Toxicity of substances in seawater was measured using growth inhibition of embryonic sea urchins during a short period after fertilization. Growth of Arbacia punctulata embryos was monitored by incorporation of tritium-labeled thymidine. The paper present...

D. E. Nacci E. Jackim

1985-01-01

96

Gene expression profiling in zebrafish embryos exposed to diclofenac, an environmental toxicant  

Microsoft Academic Search

Pharmaceuticals are continually released in the environment and therefore pollution from drugs is a pressing problem in the\\u000a environment. Diclofenac, 2-[(2,6-dichlorophenyl)amino]phenylacetic acid is a FDA approved non-steroidal anti-inflammatory\\u000a drug (NSAID) for the treatment of inflammation. This pharmaceutical has been found as pollutant in superficial waters. Danio rerio (zebrafish) embryo has been used as a model organism for acute pollutant toxicity

Bruna De Felice; Luisa Copia; Marco Guida

97

Toxicity to embryo and adult zebrafish of copper complexes with two malonic acids as models for dissolved organic matter  

SciTech Connect

The toxicity to embryo and adult zebrafish (Danio rerio) of Cu complexes with two substituted malonic acids, benzyl- and n-hexadecyl-, chosen as models for low-molecular-weight natural dissolved organic matter, were investigated. Toxicity test solutions at pH 6.5 {+-} 0.1 with the required Cu ion-specific electrode. In the absence of malonic acids, concentrations of Cu{sup 2+} up to 1.13 {mu}mol/L increased the embryo hatching time from approx. 2 d in control solutions (no Cu or malonic acid) and solutions containing malonic acids without Cu to approx. 8 d. The Cu-benzylmalonic acid complex in the presence of inorganic Cu species did not delay hatching beyond that attributable to Cu{sup 2+}. In contrast, 0.60 {mu}mol/L Cu-n-hexadecylmalonic complexes delayed hatching by 5.5 d in excess of that attributable to 1.13 {mu}mol/L Cu{sup 2+}, assuming that the hatching delays caused by the different Cu species were additive, possibly because of Cu entry into the embryo as the lipophilic Cu-n-hexadecylmalonic complex. None of the Cu-malonic acid complexes was acutely toxic to adult zebrafish at concentrations up to 1.4 {mu}mol/L, possibly because Cu was removed from the Cu-malonic acid complexes by stronger chelating groups at the gill surface. Substituted malonic acids with similar proton and Cu association constants can be readily prepared with a variety of simple substituents, radiolabeled if required. Their results show that these acids could be useful ligands for investigating intracellular transport and metabolism of metal-organic complexes.

Palmer, F.B.; Evans, C.W. [Univ. of Auckland (New Zealand); Butler, C.A. [Woodward Clyde NZ Ltd., Auckland (New Zealand); Timperley, M.H. [National Inst. of Water and Atmospheric Research, Auckland (New Zealand)

1998-08-01

98

An evaluation of propofol toxicity on mouse oocytes and preimplantation embryos.  

PubMed

Mouse biological assays were used to investigate potential adverse effects of propofol on the oocyte's competence to fuse with spermatozoa and on the embryo's ability to develop to the blastocyst stage. Cumulus-enclosed metaphase II oocytes were exposed for 1 h to 0.01, 0.1, 0.4, 1 and 10 microg/ml propofol (Diprivan) and subjected to a sperm-oocyte fusion test based on the dye (Hoechst 33342) transfer technique. Oocytes exposed to 0.4, 1 and 10 microg/ml propofol showed a significant reduction in the rate of sperm fusion and underwent pronuclei formation at a rate similar to that of sperm fusion. In a second trial, mouse 1-cell and 2-cell embryos were exposed to varying propofol concentrations for 14h and then checked for subsequent development. Although adverse effects were not observed in 2-cell embryos, treatment of 1-cell embryos with propofol concentrations ranging from 0.01 to 10 microg/ml resulted in the inhibition of cleavage to blastocyst stage. We conclude that propofol can negatively influence fertilization in the mouse by impairing the oocyte's ability to fuse with spermatozoa, without interfering with the sperm-induced activation of the cell cycle. Moreover, we document the peculiar sensitivity to propofol of mouse 1-cell embryos as compared with 2-cell embryos. PMID:9557852

Tatone, C; Francione, A; Marinangeli, F; Lottan, M; Varrassi, G; Colonna, R

1998-02-01

99

Comparative toxicity of Euphorbia milii latex and synthetic molluscicides to Biomphalaria glabrata embryos.  

PubMed

Plant molluscicides have been regarded as possible alternatives to the costly and environmentally hazardous molluscicides currently available. This study was undertaken to compare the developmental toxicity of a plant molluscicide (Euphorbia milii latex, LAT) with that of three synthetic molluscicidal compounds. Biomphalaria glabrata egg masses (0-15 h after spawning) were exposed to molluscicides for 96 h and thereafter examined up to the 14th day after spawning. Embryo deaths, abnormal embryo development (malformations) and the day of hatching were recorded. Although exhibiting a weak ovicidal effect, LAT markedly impaired the development of snail embryos at concentrations 1000 microg L(-1) and produced anomalies (EC(50)=2040 microg L(-1)) such as abnormal shells, hydropic embryos, cephalic and non-specific malformations. Embryolethal potencies of molluscicides were as follows: triphenyltin hydroxide (TPTH; LC(50)=0.30 microg L(-1))>niclosamide (NCL; LC(50)=70 microg L(-1))>copper sulphate (CuSO(4); LC(50)=2190 microg L(-1)) > LAT (LC(50)=34030 microg L(-1)). A few malformations were recorded in embryos exposed to concentrations of TPTH within the range of lethal concentrations, while almost no anomalies were noted among those treated with NCL or CuSO(4). A hatching delay (hatching on day 10 after spawning or later) was observed among LAT-exposed embryos. The effects of NCL, TPTH and CuSO4 on hatching were to some extent masked by their marked embryolethality. The no-observed effect concentrations (NOEC) for embryotoxicity were as follows: TPTH, 0.1 microg L(-1); NCL, 25.0 microg L(-1); CuSO(4), 500.0 microg L(-1) and LAT, 500.0 microg L(-1). Results from this study suggest that, although LAT was not acutely embryolethal after a short-term exposure, it markedly disrupted snail development. The marked embryotoxicity of E. milii possibly contributes to its effectiveness as a molluscicide. PMID:20594574

Oliveira-Filho, Eduardo C; Geraldino, Barbara R; Coelho, Deise R; De-Carvalho, Rosângela R; Paumgartten, Francisco J R

2010-09-01

100

Embryo toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to the wood duck (Aix sponsa)  

USGS Publications Warehouse

We examined the sensitivity of the wood duck (Aix sponsa) embryo to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injecting the toxicant into their eggs. Six groups of wood duck eggs (n = 35 to 211 per trial) were injected with 0 to 4600 pg TCDD/g egg between 2003 and 2005. Injections were made into yolk prior to incubation, and eggs were subsequently incubated and assessed weekly for mortality. Significant TCDD-induced mortality was not observed through day 25 (90% of incubation). Liver, heart, eye, and brain histology were generally unremarkable. Hepatic ethoxyresorufin-O-deethylase activity, a biomarker of dioxin-like compound exposure, was induced by 12-fold in the 4600 pg/g treatment relative to controls. The median lethal dose for chicken (Gallus domesticus) eggs we dosed identically to wood duck eggs was about 100 pg/g, similar to other assessments of chickens. Among dioxin-like compound embryo lethality data for 15 avian genera, the wood duck 4600 pg/g no-observed-effect level ranks near the middle. Because no higher doses were tested, wood ducks may be like other waterfowl (order Anseriformes), which are comparatively tolerant to embryo mortality from polychlorinated dibenzo-p-dioxins and dibenzofurans when exposed by egg injection. ?? 2008 US Government.

Augspurger, T. P.; Tillitt, D. E.; Bursian, S. J.; Fitzgerald, S. D.; Hinton, D. E.; Di, Giulio, R. T.

2008-01-01

101

The toxic effects of microcystin-LR on embryo-larval and juvenile development of loach, Misguruns mizolepis Gunthe.  

PubMed

Microcystin-LR, a specific and potent hepatotoxin, was tested for its effects on loach embryo-larval and juvenile development. The results of this study showed that loach embryos were more sensitive when exposed to microcystin-LR at a later than at an earlier stage of development. Juveniles were far less sensitive to MC-LR than were embryos and larvae. Mortality and developmental abnormality were proven to be dose-dependent and to be stage-specific sensitive. Among the abnormal changes noted were: pericardial edema and tubular heart, bradycardia, homeostasis, poor yolk resumption, small head, curved body and tail, and abnormal hatching. Liver and heart were the main targets of microcystin-LR toxicity. Ultrastructural analysis documented a complex set of sublethal effects of microcystin-LR on loach hepatocytes, chiefly including morphological alteration in nuclear and RER of loach liver cells. In addition, microcystin-LR was lethal to loach juvenile in the subacute (7 days) exposure (LC(50)=593.3 microg/l). PMID:11738232

Liu, Yongding; Song, Lirong; Li, Xiaoyu; Liu, Tongming

2002-04-01

102

Chronic toxicity of heavy fuel oils to fish embryos using multiple exposure scenarios.  

PubMed

The chronic toxicity to rainbow trout (Oncorhynchus mykiss) embryos of heavy fuel oil (HFO) 6303, weathered HFO 6303, HFO 7102, and medium South American (MESA) crude oil was assessed by different exposure regimes. These included water accommodated fractions (WAF; water in contact with floating oil), chemically enhanced WAF (CEWAF; oil dispersed with Corexit 9500), and effluent from columns of gravel coated with stranded oil. Heavy fuel oil WAF was nontoxic and did not contain detectable concentrations of hydrocarbons, likely because the high density and viscosity of HFO prevented droplet formation. In contrast, chemically dispersed HFO and effluent from columns of stranded HFO contained measurable concentrations of alkyl polycyclic aromatic hydrocarbons (PAH), coincident with embryo toxicity. These exposure regimes enhanced the surface area of oil in contact with water, facilitating oil-water partitioning of hydrocarbons. Heavy fuel oil was consistently more toxic to fish than crude oil and the rank order of alkyl PAH concentrations in whole oil were sufficient to explain the rank order of toxicity, regardless of exposure method. Thus, the propensity of HFO to sink and strand in spawning shoals creates a long-term risk to developing fish because of the sustained release of PAHs from HFO to interstitial waters. Further, PAH monitoring is key to accurate risk assessment. PMID:24464524

Martin, Jonathan D; Adams, Julie; Hollebone, Bruce; King, Thomas; Brown, R Stephen; Hodson, Peter V

2014-03-01

103

Use of toxicogenomics to predict the potential toxic effect of Benzo(a)pyrene on zebrafish embryos: Ocular developmental toxicity.  

PubMed

Benzo(a)pyrene (BaP) is a representative polycyclic aromatic hydrocarbon (PAH), which is ubiquitous in the environment. The toxic effects of BaP on fish embryos have been described in detail, but some potentially toxic effects of BaP might have been neglected owing to the limitations of traditional techniques. In the present research, global transcriptional patterns were used to study the potentially toxic effects of BaP, as well as its underlying toxicological mechanisms. The expression levels of multiple genes were significantly changed by BaP exposure. The results of ontology assignments and cluster analysis showed that BaP could affect the processes of photoreceptor maintenance and phototransduction. We also conducted an experiment on phototactic response and found that larvae exposed to BaP displayed a decreasing response to light. In addition, BaP exposure decreased the cellular density of the ganglion cell layer (GCL) significantly. These results suggested that BaP exposure induced visual system developmental defects and dysfunction by perturbation of photoreceptor development related genes. Our results were helpful for an understanding of the toxicity of BaP. This study also indicated that microarray analysis was effective for predicting the potential toxicity of chemicals with high sensitivity and accuracy. PMID:24875912

Huang, Lixing; Zuo, Zhenghong; Zhang, Youyu; Wu, Meifang; Lin, Jackie Jin; Wang, Chonggang

2014-08-01

104

Embryos without secrets: an expert panel study on comprehensive embryo testing and the responsibility of the clinician.  

PubMed

The introduction of comprehensive testing techniques, such as microarray technology or whole genome sequencing, in embryo testing has the potential to change the practice of Preimplantation Genetic Diagnosis (PGD) and Preimplantation Genetic Screening (PGS). However, the extra information these procedures yield may potentially generate dilemmas for couples and professionals regarding the scope of the tests and the selection of the right embryo. In order to understand this complexity and reflect on its consequences, we organized two expert panels consisting of professionals working in the field of assisted reproduction and/or genetics. We found that there is great uncertainty amongst professionals how to tackle questions related to comprehensive screening, such as which conditions to test for and who should have the final say on which embryo to select, and a lack of a framework from which such questions can be answered. Moreover, the complexity of genetic information comprehensive tests may yield may make it impossible to select the best embryo altogether. PMID:23131419

Hens, Kristien; Dondorp, Wybo; de Wert, Guido

2013-02-01

105

Toxicity of spill-treating agents and oil to sea urchin embryos.  

PubMed

The aim of this study was to assess the joint toxicity of a Maya crude oil and four spill-treating agents (STAs) (CytoSol, Finasol OSR51, Agma OSD569 and OD4000). The acute toxicity of the binary mixtures of the water accommodated fractions (WAFs) obtained independently for the oil and each STA was assessed. The toxicity of the chemically enhanced WAF (CEWAF) of oil and Finasol OSR51 at several dispersant to oil ratios (1:2, 1:10 and 1:100) was also evaluated. The toxicity (EC50) obtained for the WAFs of the STAs was: CytoSol (15.1 mL/L)toxicity of binary mixtures was obtained by the following models: Concentration Addition (Agma OSD569 and CytoSol), Independent Action (Finasol OSR51) and extended Concentration Addition model to describe antagonistic effects (OD4000). The CEWAFs showed an intermediate position between the more moderate effects of the WAF of oil and the higher toxicity of the WAFs of Finasol OSR51, which suggested the high sensitivity of the sea urchin embryo toward the dispersant. PMID:24295747

Rial, Diego; Vázquez, José A; Murado, Miguel A

2014-02-15

106

BIOEQUIVALENCE APPROACH FOR WHOLE EFFLUENT TOXICITY TESTING  

EPA Science Inventory

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

107

TOXICITY OF GLYPHOSATE AND TRICLOPYR USING THE FROG EMBRYO TERATOGENESIS ASSAY—XENOPUS  

Microsoft Academic Search

The effects of glyphosate ((N-phosphonomethyl)glycine) and triclopyr (((3,5,6-trichloro-2-pyridinyl)oxy)acetic acid) on the embryonic development of Xenopus laeviswere evaluated using Frog Embryo Teratogenesis Assay— Xenopus(FETAX). Rodeot, the isopropylamine (ipa) salt of glyphosate formulated without a surfactant was found to be the least toxic, with a LC5 and LC50 of 3,779 and 5,407 mg acid equivalent (AE)\\/L, respectively. The LC5 and LC50 of

Peggy J. Perkins; Herman J. Boermans; Gerald R. Stephenson

2000-01-01

108

Toxicity of cylindrospermopsin, and other apparent metabolites from Cylindrospermopsis raciborskii and Aphanizomenon ovalisporum, to the zebrafish (Danio rerio) embryo  

PubMed Central

Cyanobacteria produce a diverse array of toxic or otherwise bioactive compounds that pose growing threats to human and environmental health. We utilized the zebrafish (Danio rerio) embryo, as a model of vertebrate development, to investigate the inhibition of development pathways (i.e. developmental toxicity) by the cyanobacterial toxin, cylindrospermopsin (CYN), as well as extracts from various isolates of Cylindrospermopsis raciborskii and Aphanizomenon ovalisporum. CYN was toxic only when injected directly into embryos, but not by direct immersion at doses up to 50 ?g/ml. Despite the dose dependency of toxicity observed following injection of CYN, no consistent patterns of developmental defects were observed, suggesting that toxic effects of CYN may not target specific developmental pathways. In contrast, direct immersion of embryos in all of the extracts resulted in both increased mortality and reproducible, consistent, developmental dysfunctions. Interestingly, there was no correlation of developmental toxicity observed for these extracts with the presence of CYN or with previously reported toxicity for these strains. These results suggest that CYN is lethal to zebrafish embryos, but apparently inhibits no specific developmental pathways, whereas other apparent metabolites from C. raciborskii and A. ovalisporum seem to reproducibly inhibit development in the zebrafish model. Continued investigation of these apparent, unknown metabolites is needed.

Berry, John P.; Gibbs, Patrick D.L.; Schmale, Michael C.; Saker, Martin L.

2012-01-01

109

Toxicity screening of produced water extracts in a zebrafish embryo assay.  

PubMed

Produced water is the largest effluent discharge from oil and gas/condensate production facilities in the North Sea. There is concern that contaminants originating from the reservoir and chemicals used in the production process may affect marine organisms. Developmental toxicity of extractable organic compounds in produced water effluents from oil and gas/condensate production platforms in the Norwegian sector of the North Sea was assessed in a temporal and spatial manner using zebrafish (Danio rerio) embryos. Large-scale solid-phase extraction (SPE) and on-column fractionation of water-soluble fraction (WSF) and an oil/particulate fraction was used in a rapid screening bioassay for embryotoxicity. Exposure to produced water extracts increased rate of mortality and reduced pigmentation and heart rate, as well as delaying time to hatch. The oil/particulate fraction was 10-fold less toxic than WSF, indicating that toxicity was predominantly produced by moderately polar and bioavailable compounds. Large spatial and temporal variation in produced water toxicity was observed, displaying considerable variability in the reservoir, oil well, and effluent composition over time. The noted toxicity did not correlate well with either reported produced water composition or parameters such as total hydrocarbons, thus challenging chemical measurements as a reliable source of information for predicting complex effects. Although embryotoxicity was observed following exposure to the extracts, dilution and transformation of produced water in the recipient are expected to rapidly reduce the concentrations of compounds in the effluents to levels below the thresholds of observed effects. PMID:24754395

Carlsson, G; Norrgren, L; Hylland, K; Tollefsen, K E

2014-01-01

110

Toxicity, uptake kinetics and behavior assessment in zebrafish embryos following exposure to perfluorooctanesulphonicacid (PFOS)  

PubMed Central

Perfluorooctanesulphonicacid (PFOS), a persistent organic contaminant, has been widely detected in the environment, wildlife and humans, but few studies have assessed its effect on aquatic organisms. The present study evaluated the effect of PFOS on zebrafish embryos. Zebrafish embryos exhibited bent spine and developmental toxicity after exposure to various PFOS concentrations (0.01-16.0 ?M) from 6 to 120 hour post-fertilization (hpf). The LC50 at 120 hpf was 4.39 ?M and the EC50 at 120 hpf was 2.23 ?M. PFOS induced apoptosis at 24 hpf was consistently located in the brain, eye, and tail region of embryos. PFOS elevated the basal rate of swimming after 4 days of exposure, and larvae exposed to PFOS (0.5-8.0?M) for only 1 h at 6 dpf swam faster with increasing PFOS concentration. Larvae exposed to 16.0 ?M PFOS for 24 h periods from 1 to 121 hpf showed the highest incidence of malformations in the 97-121 hpf window. Continuous exposure to PFOS from 1 to 121 hpf resulted in a steady accumulation with no evidence of elimination. Our results further the understanding of the health risks of PFOS to aquatic organisms and identify additional research needed on PFOS toxicology.

Huang, Haihua; Huang, Changjiang; Wang, Lijun; Ye, Xiaowei; Bai, Chenglian; Simonich, Michael T.; Tanguay, Robert L.; Dong, Qiaoxiang

2014-01-01

111

Improved in vitro development of cloned bovine embryos using S-adenosylhomocysteine, a non-toxic epigenetic modifying reagent.  

PubMed

In this study, fibroblast cells were stably transfected with mouse POU5F1 promoter-driven enhanced green fluorescent protein (EGFP) to investigate the effect of S-adenosylhomocysteine (SAH), the reversible non-toxic inhibitor of DNA-methyltransferases (DNMTs), at different intervals post-fusion on in vitro development of cloned bovine embryos. Treatment with SAH for 12?hr resulted in 54.6?±?7.7% blastocyst production, which was significantly greater than in vitro fertilized embryos (IVF: 37.2?±?2.7%), cloned embryos treated with SAH for 72?hr (31.0?±?7.6%), and control cloned embryos (34.6?±?3.6%). The fluorescence intensities of the EGFP-POU5F1 reporter gene at all intervals of SAH treatment, except of 72?hr, were significantly higher than control somatic cell nuclear transfers (SCNT) embryos. The intensity of DNA-methylation in cloned embryos treated with SAH for 48?hr was similar to that of IVF embryos, and was significantly lower than the other SCNT groups. The levels of H3K9 acetylation in all SCNT groups were significantly lower than IVF embryos. Real-time PCR analysis of gene expression revealed significantly higher expression of POU5F1 in cloned versus IVF blastocysts. Neither embryo production method (SCNT vs. IVF) nor the SAH treatment interval affected expression of the BCL2 gene. Cloned embryos at all intervals of SAH treatment, except for 24?hr, had significantly increased VEGF transcript compared to IVF and control SCNT embryos. It was suggested that the time interval of DNMT inhibition may have important consequences on different in vitro features of bovine SCNT, and the improving effects of DNMT inhibition on developmental competency of cloned embryos are restricted to a specific period of time preceding de novo methylation. PMID:21721066

Jafari, Shahram; Hosseini, Morteza S; Hajian, Mahdi; Forouzanfar, Mohsen; Jafarpour, Farnoosh; Abedi, Parvaneh; Ostadhosseini, Somayyeh; Abbasi, Hassan; Gourabi, Hamid; Shahverdi, Abdol H; Dizaj, Ahmad Vosough Taghi; Anjomshoaa, Maryam; Haron, Wahid; Noorshariza, Noor; Yakub, Halimhatoon; Nasr-Esfahani, Mohammad H

2011-08-01

112

INCREASING THE USEFULNESS OF ACUTE TOXICITY TESTS  

EPA Science Inventory

The conceptually and practically simple acute toxicity test provides information that is useful in the protection of aquatic life from pollution. Standardization increases the usefulness of routine acute tests by increasing their quality and comparability and allowing the study o...

113

Developmental toxicity of treated municipal wastewater effluent on Bombina orientalis (Amphibia: Anura) embryos.  

PubMed

Amphibian populations have been decreasing in urban freshwater systems in Korea. To elucidate the biological safety of treated wastewater effluent (TWE) in the Tancheon basin, the capital area of Korea, a 7-d-exposure Bombina orientalis embryo developmental toxicity assay was examined during the breeding season. In March, there were no significant differences in embryonic survival or malformation among the water samples. In July, following monsoon precipitation, embryonic lethality in TWE was significantly higher than in the upstream water sample. Malformation in TWE and TWE-mixed waters was significantly higher than in the control and upstream water samples. Tail muscle height of tadpoles also significantly decreased in TWE and TWE-mixed waters. Heavy metals were not detected in any samples. Total nitrogen, total phosphorous, and chemical oxygen demand in TWE markedly increased together with a decrease in dissolved oxygen in July. The increase in organic and inorganic loading following precipitation could have made TWE and TWE-mixed water not suitable for embryonic development. Though being managed based on physicochemical criteria, the water quality of TWE may not be sufficient to assure normal development of amphibian embryos. An amphibian developmental toxicity assay would be helpful for the water-quality management of TWE and urban freshwater systems in Korea. PMID:24436004

Park, Chan Jin; Ahn, Hyo Min; Cho, Seong Chan; Kim, Tae-Hoon; Oh, Jong-Min; Ahn, Hong Kyu; Chun, Seung-Hoon; Gye, Myung Chan

2014-04-01

114

Selecting optimal eggs and embryonic developmental stages of fathead minnow (Pimephales promelas) for early life-stage toxicity tests.  

PubMed

Aquaculture research has indicated that fish embryo hatching success and larval survival can sometimes be predicted by embryo characteristics, such as blastomere cleavage patterns. An analogous strategy of individual assessment of spawned eggs could also be used to improve the quality of toxicity tests using early life-stages of fish where control-group survival determines experimental validity. Here we explored whether a simple method of assessing fathead minnow eggs and embryos for abnormalities could predict hatch success, and larval size at hatch, as indicators of embryo larval quality. Embryos were classified according to both their developmental stage and the presence of any abnormalities: uneven blastomere cleavage, atypical embryo size or shape, and the presence of inclusions in the yolk. Clutch size and fertilization rate did not predict embryo larval quality. Fewer abnormalities in embryos with ?32 cells correlated with longer larvae at hatch. Normal embryos were more likely to hatch successfully than abnormal embryos of the same clutch, but because abnormality rates were generally low, much of the variation in hatch success could not be attributed to visible embryo malformations. Blastomere symmetry may be a useful selection criterion in embryos <3 h postfertilization. Where toxicant exposures early in embryonic development are not required or possible, hatch success could be increased by using older embryos that have survived gastrulation. Purposeful selection of embryos with at least two blastomeres, blastomere symmetry, and few inclusions can improve control survival and improve the quality of any generated (sub)lethality data. In our laboratory, application of the egg-selection criteria significantly improved control group hatch success increasing it from a mean of 84.4 to 94.2%. PMID:24346244

Marentette, Julie R; Chiorean, Sorina; Lavalle, Christine; Sullivan, Cheryl; Parrott, Joanne L

2014-02-01

115

Acute ZnO nanoparticles exposure induces developmental toxicity, oxidative stress and DNA damage in embryo-larval zebrafish.  

PubMed

Nano-scale zinc oxide (nano-ZnO) is widely used in various industrial and commercial applications. However, the available toxicological information was inadequate to assess the potential ecological risk of nano-ZnO to aquatic organisms and the publics. In this study, the developmental toxicity, oxidative stress and DNA damage of nano-ZnO embryos were investigated in the embryo-larval zebrafish, the toxicity of Zn(2+) releasing from nano-ZnO were also investigated to ascertain the relationship between the nano-ZnO and corresponding Zn(2+). Zebrafish embryos were exposed to 1, 5, 10, 20, 50, and 100mg/L nano-ZnO and 0.59, 2.15, 3.63, 4.07, 5.31, and 6.04 mg/L Zn(2+) for 144 h post-fertilisation (hpf), respectively. Up to 144 hpf, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and malondialdehyde (MDA) contents, the genes related to oxidative damage, reactive oxygen species (ROS) generation and DNA damage in zebrafish embryos were measured. The nano-ZnO was found to exert a dose-dependent toxicity to zebrafish embryos and larvae, reducing the hatching rate and inducing malformation and the acute toxicity to zebrafish embryos was greater than that of the Zn(2+) solution. The generation of ROS was significantly increased at 50 and 100mg/L nano-ZnO. DNA damage of zebrafish embryo was evaluated by single-cell gel electrophoresis and was enhanced with increasing nano-ZnO concentration. Moreover, the transcriptional expression of mitochondrial inner membrane genes related to ROS production, such as Bcl-2, in response to oxidative damage, such as Nqo1, and related to antioxidant response element such as Gstp2 were significantly down-regulated in the nano-ZnO treatment groups. However, the nano-ZnO up-regulated the transcriptional expression of Ucp2-related to ROS production. In conclusion, nano-ZnO induces developmental toxicity, oxidative stress and DNA damage on zebrafish embryos and the dissolved Zn(2+) only partially contributed to the toxicity of nano-ZnO. The adverse effects of nano-ZnO may be the important mechanisms of its toxicity to zebrafish embryos. PMID:23643724

Zhao, Xuesong; Wang, Shutao; Wu, Yuan; You, Hong; Lv, Lina

2013-07-15

116

METHOD FOR EARLY LIFE-STAGE TOXICITY TESTS USING THREE ATHERINID FISHES AND RESULTS WITH CHLORPYRIFOS  

EPA Science Inventory

The authors have developed methods for obtaining embryos and conducting early life-stage toxicity tests (continuous exposure from the embryonic stage to approximately three weeks or more into the exogenous feeding stage) with three estuarine species of atherinid fishes. Early lif...

117

EARLY LIFE-STAGE TOXICITY TEST METHODS FOR GULF TOADFISH, 'OPSANUS BETA', AND RESULTS USING CHLORPYRIFOS  

EPA Science Inventory

Gulf toadfish (Opsanus beta) were continuously exposed as embryos, sac fry and juveniles to technical chlorpyrifos in two 49-day early life-stage toxicity tests. Survival was significantly (alpha = 0.05) reduced only in 150 micrograms/l). However, toadfish exposed to chlorpyrifos...

118

9 CFR 113.37 - Detection of pathogens by the chicken embryo inoculation test.  

Code of Federal Regulations, 2010 CFR

...inoculated on the chorio-allantoic membrane (CAM) with 0.1 ml, and in the allantoic sac...for a valid test. Examine all embryos and CAM's from embryos which die after the first...post-inoculation and the surviving embryos (including CAM's) examined. (d) If death...

2009-01-01

119

Synthesis, physicochemical studies, embryos toxicity and DNA interaction of some new Iron(II) Schiff base amino acid complexes  

NASA Astrophysics Data System (ADS)

New Fe(II) Schiff base amino acid complexes derived from the condensation of o-hydroxynaphthaldehyde with L-alanine, L-phenylalanine, L-aspartic acid, L-histidine and L-arginine were synthesized and characterized by elemental analysis, IR, electronic spectra, and conductance measurements. The stoichiometry and the stability constants of the complexes were determined spectrophotometrically. The investigated Schiff bases exhibited tridentate coordination mode with the general formulae [Fe(HL)2]·nH2O for all amino acids except L-histidine. But in case of L-histidine, the ligand acts as tetradentate ([FeL(H2O)2]·2H2O), where HL = mono anion and L = dianion of the ligand. The structure of the prepared complexes is suggested to be octahedral. The prepared complexes were tested for their toxicity on chick embryos and found to be safe until a concentration of 100 ?g/egg with full embryos formation. The interaction between CT-DNA and the investigated complexes were followed by spectrophotometry and viscosity measurements. It was found that, the prepared complexes bind to DNA via classical intercalative mode and showed a different DNA cleavage activity with the sequence: nhi > nari > nali > nasi > nphali. The thermodynamic Profile of the binding of nphali complex and CT-DNA was constructed by analyzing the experimental data of absorption titration and UV melting studies with the McGhee equation, van't Hoff's equation, and the Gibbs-Helmholtz equation.

Abdel-Rahman, Laila H.; El-Khatib, Rafat M.; Nassr, Lobna A. E.; Abu-Dief, Ahmed M.

2013-05-01

120

In Vivo Quantitative Study of Sized-Dependent Transport and Toxicity of Single Silver Nanoparticles Using Zebrafish Embryos  

PubMed Central

Nanomaterials possess distinctive physicochemical properties (e.g., small sizes, high surface area-to-volume ratios) and promise a wide variety of applications, ranging from design of high quality consumer products to effective disease diagnosis and therapy. These properties can lead to toxic effects, potentially hindering advance in nanotechnology. In this study, we have synthesized and characterized purified and stable (non-aggregation) silver nanoparticles (Ag NPs, 41.6±9.1 nm in average diameters), and utilized early-developing (cleavage-stage) zebrafish embryos (critical aquatic and eco- species) as in vivo model organisms to probe diffusion and toxicity of Ag NPs. We found that single Ag NPs (30–72 nm diameters) passively diffused into the embryos through chorionic pores via random Brownian motion and stayed inside the embryos throughout their entire development (120 hours-post-fertilization, hpf). Dose and size dependent toxic effects of the NPs on embryonic development were observed, showing the possibility of tuning biocompatibility and toxicity of the NPs. At lower concentrations of the NPs (? 0.02 nM), 75–91% of embryos developed to normal zebrafish. At the higher concentrations of NPs (? 0.20 nM), 100% of embryos became dead. At the concentrations in between (0.02–0.2 nM), embryos developed to various deformed zebrafish. Number and sizes of individual Ag NPs embedded in tissues of normal and deformed zebrafish at 120 hpf were quantitatively analyzed, showing deformed zebrafish with higher number of larger NPs than normal zebrafish, and size-dependent nanotoxicity. By comparing with our previous studies of smaller Ag NPs (11.6±3.5 nm), the results further demonstrate striking size-dependent nanotoxicity that, at the same molar concentration, the larger Ag NPs (41.6±9.1 nm) are more toxic than the smaller Ag NPs (11.6±3.5 nm).

Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Desai, Tanvi; Cherukui, Pavan K.; Xu, Xiao-Hong Nancy

2012-01-01

121

Literature review on duckweed toxicity testing.  

PubMed

Duckweed commonly refers to a group of floating, flowering plants of the family Lemnaceae. Duckweed plants are fast growing and widely distributed. They are easy to culture and to test. Some reports suggest that duckweed plants are tolerant to environmental toxicity. Other studies, however, indicate that duckweed plants are as sensitive to toxicity as other aquatic species. Duckweed plants are especially suitable for use in complex effluent bioassays, and for testing herbicide pollution in the aquatic environment, lake and river pollution, sediment toxicity, and the like. Duckweed and algae represent different levels of complexity in the plant kingdom. They complement each other as phytotoxicity test organisms, instead of mutually excluding each other. Many duckweed species have been studied, primarily of the Lemna and Spirodela genera. Lemna minor and L. gibba have been recommended as standard test species. Differences in duckweed test methodology occur with regard to test types, test vessels, control tests, nutrient media, end points, and applications. PMID:2190824

Wang, W

1990-06-01

122

Comparison of standard acute toxicity tests with rapid-screening toxicity tests  

SciTech Connect

This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus ccalyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photo bacterium phosphoreum - Microtox test, and a mixture of bacterial species - the polytox test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriadaphnta dubia), green algae (Setenastrum capricarnutum), fathead minnows (Pimephalespromelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC5O/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

Toussaint, M.W.; Shedd, T.R.; VanDerSchal, W.H.; Leather, G.R.

1995-10-01

123

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

SciTech Connect

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

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

1995-05-01

124

REGULATORY APPLICATIONS OF POREWATER TOXICITY TESTING  

EPA Science Inventory

The purpose of this chapter is to evaluate the use of porewater toxicity tests in regulatory applications, including their potential use in the development of sediment quality guideline (SQG) values. Specifically, the following discussion focuses on the appropriateness and readin...

125

Toxicity of endosulfan on embryo-larval development of the South American toad Rhinella arenarum.  

PubMed

Endosulfan is a widely used pesticide despite its extreme toxicity to a variety of taxa and its worldwide ban. The aim of the present study was to evaluate the acute and chronic toxicity of endosulfan on the embryonic-larval development of the common South American toad Rhinella arenarum. The results showed that lethal and sublethal effects increased with concentration and exposure time. The sensitivity to endosulfan increased during the larval period, the complete operculum stage (S.25) being the most sensitive (504-h median lethal concentration [LC50]?=?0.01 mg endosulfan/L; 10% lethal concentration [LC10]?=?0.004 mg endosulfan/L). Endosulfan exposure caused morphological abnormalities such as general underdevelopment, edema, gill malformations, and cellular dissociation as well as neurotoxicity. Our results also showed that larvae exposed to concentrations of 0.005 mg endosulfan/L and 0.01 mg endosulfan/L completed metamorphosis earlier than controls, but with underdevelopment. The 240-h teratogenic index was 6.13, implying a high risk for embryos to be malformed in the absence of significant embryonic lethality. Because the hazard quotients for chronic exposure were over 1, the level of concern value and toxicity endpoints obtained in the present study for R. arenarum occurred at concentrations lower than the levels of endosulfan reported in the environment, this pesticide should be considered a potential risk for this species. PMID:24375551

Svartz, Gabriela V; Wolkowicz, Ianina R Hutler; Coll, Cristina S Pérez

2014-04-01

126

RAPID AQUATIC TOXICITY ASSAY USING INCORPORATION OF TRITIATED-THYMIDINE INTO SEA URCHIN, 'ARBACIA PUNCTULATA', EMBRYO: EVALUATION OF TOXICANT EXPOSURE PROCEDURES  

EPA Science Inventory

Toxicity of substances in seawater was measured using growth inhibition of embryonic sea urchins during a short period after fertilization. Growth of Arbacia punctulata embryos was monitored by incorporation of tritium-labeled thymidine. The paper presents a comparison of toxican...

127

Developmental toxicity and stress protein responses in zebrafish embryos after exposure to diclofenac and its solvent, DMSO  

Microsoft Academic Search

One of the most frequently detected pharmaceuticals in environmental water samples is the anti-rheumatic drug, diclofenac. Despite its increasing environmental significance, investigations concerning the effects of this drug on the early developmental stages of aquatic species are lacking up to now. To determine the developmental toxicity and proteotoxicity of this drug on the growing fish embryos, eggs of zebrafish were

A. V. Hallare; H.-R. Köhler; R. Triebskorn

2004-01-01

128

Toxicity evaluation of ?-diketone antibiotics on the development of embryo-larval zebrafish (danio rerio).  

PubMed

This study evaluated the effects of ?-diketone antibiotics (DKAs) on the development of embryo-larval zebrafish (Danio rerio). When exposure to DKAs, developmental malformations, such as hatching delay, curved body axis, pericardial edema, uninflated swim bladder and yolk sac edema, were observed at 120 h postfertilization (hpf). The estimated 120 hpf nominal concentrations of no observed effect concentration and lowest observed effect concentration for DKAs were 18.75 and 37.50 mg/L, respectively, suggesting that DKAs have much lower toxicity than other persistent pollutants. Following DKA exposure, embryonic heart rates were significantly reduced as compared to the controls at 48 and 60 hpf. The peak bending motion frequency appeared 1 h earlier than in control embryos. The 2.34 and 9.38-mg/L treatment groups had a higher basal swim rate than control groups at 120 hpf in both light and light-to-dark photoperiod experiments. The occurrence of high speed swim rates was enhanced approximately threefold to sevenfold in the 2.34 and 9.38 mg/L treatments compared to the control. Glutathione (GSH) concentrations in the 2.34 and 9.38-mg/L treatments were significantly higher than the control at 72 hpf, suggesting that GSH production was induced at the end of the hatching period. When exposed to DKAs, zebrafish superoxide dismutase enzyme (SOD) activities were significantly inhibited in the early embryonic period, demonstrating that the clearing ability in zebrafish was lower than the generation rate of free radicals. In summary, the combined DKAs were developmentally toxic to zebrafish in their early life stages and had the ability to impair individual behaviors that are of great importance in the assessment of their ecological fitness. © 2013 Wiley Periodicals, Inc. Environ Toxicol, 2013. PMID:23364946

Wang, Huili; Che, Baoguang; Duan, Ailian; Mao, Jingwen; Dahlgren, Randy A; Zhang, Minghua; Zhang, Hongqin; Zeng, Aibing; Wang, Xuedong

2013-01-30

129

Chironomidae Toxicity Tests--Biological Background and Procedures.  

National Technical Information Service (NTIS)

Toxicity tests must be based on an understanding of the test animal's life cycle. The first section of this report describes the biological information needed to develop toxicity test procedures. The second section describes three categories of toxicity t...

R. L. Anderson

1980-01-01

130

Toxicity assessment of TiO? nanoparticles in zebrafish embryos under different exposure conditions.  

PubMed

The popularity of TiO2 nanoparticles (nano-TiO2) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO2 under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96h to different concentrations of nano-TiO2 in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO2 appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the factors involved in the toxicity of these nanoparticles, as well as to the establishment of protocols for risk assessments of nanotechnology. PMID:24418748

Clemente, Z; Castro, V L S S; Moura, M A M; Jonsson, C M; Fraceto, L F

2014-02-01

131

Automated zebrafish chorion removal and single embryo placement: optimizing throughput of zebrafish developmental toxicity screens.  

PubMed

The potential of the developing zebrafish model for toxicology and drug discovery is limited by inefficient approaches to manipulating and chemically exposing zebrafish embryos-namely, manual placement of embryos into 96- or 384-well plates and exposure of embryos while still in the chorion, a barrier of poorly characterized permeability enclosing the developing embryo. We report the automated dechorionation of 1600 embryos at once at 4 h postfertilization (hpf) and placement of the dechorionated embryos into 96-well plates for exposure by 6 hpf. The process removed ?95% of the embryos from their chorions with 2% embryo mortality by 24 hpf, and 2% of the embryos malformed at 120 hpf. The robotic embryo placement allocated 6-hpf embryos to 94.7% ± 4.2% of the wells in multiple 96-well trials. The rate of embryo mortality was 2.8% (43 of 1536) from robotic handling, the rate of missed wells was 1.2% (18 of 1536), and the frequency of multipicks was <0.1%. Embryo malformations observed at 24 hpf occurred nearly twice as frequently from robotic handling (16 of 864; 1.9%) as from manual pipetting (9 of 864; 1%). There was no statistical difference between the success of performing the embryo placement robotically or manually. PMID:22357610

Mandrell, David; Truong, Lisa; Jephson, Caleb; Sarker, Mushfiqur R; Moore, Aaron; Lang, Christopher; Simonich, Michael T; Tanguay, Robert L

2012-02-01

132

TOXIC SUBSTANCES CONTROL ACT TEST SUBMISSIONS (TSCATS)  

EPA Science Inventory

Toxic Substances Control Act Test Submissions (TSCATS) is an online index to unpublished, nonconfidential studies covering chemical testing results and adverse effects of chemicals on health and ecological systems. The studies are submitted by U.S. industry to EPA under several s...

133

Estimating the gasoline components and formulations toxicity to microalgae (Tetraselmis chuii) and oyster (Crassostrea rhizophorae) embryos: An approach to minimize environmental pollution risk  

SciTech Connect

Even though petrochemical contamination frequently occurs in the form of oil spills, it is thought that a greater danger to coastal habitats is posed by chronic petrochemical toxicity associated with urban run-off, in which gasoline water-soluble-fraction (WSF) plays an important role. The hypothesis of the entrepreneurs, who were associated to the scientists uncharged of this research, was that recycled petrochemical waste may provide different gasoline formulations, having different toxic properties; the correlation between the gasoline formulations and their components' toxicological effects might contribute to the reformulation of the products, in such a way that the gasoline generated could be less toxic and less harmful to the environment. The aim of this research was to determine the toxic effects of 14 different types of gasoline (formulated, in accordance with National Petroleum Agency standards, from petrochemical waste), on Tetraselmis chuii (microalgae culture) and Crassostrea rhizophorae (embryos). Microalgae and oyster embryos were exposed to different gasoline formulations water-soluble fractions (WSF) at a range of concentrations (0%, 4.6%, 10.0%, 22.0%, 46.0%, and 100%), for 96 and 24 h, respectively. The tests were carried out under controlled conditions. End-points have been CI50-96h (concentration causing 50% growth inhibition in microalgae cultures) and EC50-24h (concentration causing abnormalities on 50% of the exposed embryos). Through these procedures, gasoline formulations, which represent the lowest environmental risk, were selected. Bioassays carried out on the 8 different gasoline components aimed to correlate gasoline toxicity with the toxic potential of its components. The analysis of principal components showed that the C9DI, a mixture of aromatic hydrocarbons of 9 carbon atoms, had the highest level of toxic potential, followed by C9S (a mixture of aromatics with 9-11 carbon atoms) and heavy naphtha. The results showed gasoline formulations 1-4 (monoaromatic hydrocarbons being the most conspicuous components) to be the least toxic, whilst formulations 12-14 (having higher content of C9DI, C9S and naphtha) were found to be the most harmful to organisms. This study led to the identification of the most toxic WSF gasoline components (C9DI and C9S), and to the possibility of developing more eco-compatible gasoline formulations.

Paixao, J.F. [Institute of Biology, Federal University of Bahia (Brazil); Nascimento, I.A. [Institute of Biology, Federal University of Bahia (Brazil) and Technology and Sciences Faculty, Salvador, Bahia (Brazil)]. E-mail: iracema@ftc.br; Pereira, S.A. [Institute of Biology, Federal University of Bahia (Brazil); Leite, M.B.L. [Institute of Biology, Federal University of Bahia (Brazil); Technology and Sciences Faculty, Salvador, Bahia (Brazil); Carvalho, G.C. [Institute of Biology, Federal University of Bahia (Brazil); BRASKEM, Petrochemical Complex, Camacari, Bahia (Brazil); Silveira, J.S.C. [BRASKEM, Petrochemical Complex, Camacari, Bahia (Brazil); Reboucas, M. [BRASKEM, Petrochemical Complex, Camacari, Bahia (Brazil); Matias, G.R.A. [Institute of Biology, Federal University of Bahia (Brazil); Rodrigues, I.L.P. [Institute of Biology, Federal University of Bahia (Brazil)

2007-03-15

134

Evaluation of effectiveness of EDTA and sodium thiosulfate in removing metal toxicity toward sea urchin embryo-larval applying the TIE.  

PubMed

Since the development of the TIE (Toxicity Identification and Evaluation) in 1988 it has been assumed that the capacity of EDTA and sodium thiosulfate to complex some metals, and thus remove their toxicity, can be applied to both freshwater and seawater ecotoxicological tests and the results subsequently interpreted. However, it is now known that there is a wide variability in the extent of this complexation. In this context, the removal of toxicity caused by the presence of Hg(2+), Cd(2+), Cu(2+), Cr(6+), Zn(2+), Ni(2+), Pb(2+), Ag(1+) and Se(2+), through metal complexation by EDTA and sodium thiosulfate, in relation to the performance of embryo-larval tests with the sea urchin Arbacia lixula was investigated. It was observed that EDTA was capable of removing the toxicity of Pb(2+), Zn(2+) and Cu(2+) while sodium thiosulfate only reduced the toxicity of Ag(1+). Compared to the complexation observed in freshwater ecotoxicological tests, the complexing agents used in this study (EDTA and sodium thiosulfate) have a lower capacity to complex metals in the marine ecotoxicological test with A. lixula. PMID:22627151

Resgalla, C; Poleza, F; Souza, R C; Máximo, M V; Radetski, C M

2012-09-01

135

Prenatal toxicity test of Morinda citrifolia (noni) fruit.  

PubMed

Morinda citrifolia (noni) fruit juice use has increased greatly within the past decade, with more than 80,000,000 liters being consumed world wide. With increasing widespread use and the potential use among pregnant women, a prenatal developmental toxicity test was conducted to further evaluate the safety of noni juice. Freeze-dried noni fruit puree from French Polynesia was administered daily by gastric intubation to separate dose groups (n = 12) of pregnant Sprague Dawley rats at 1.72, 3.43, and 6.86 g/kg body weight, with a control group receiving water in place of noni. The dose schedule was followed from the first day of gestation until one day prior to expected delivery, 21 days. There were no symptoms of toxicity in the pregnant dams. There was no difference between the control and any noni group in the number of live fetuses, resorptions, fetal weight and length, or skeletal abnormalities. No dead fetuses, gross external malformations, or internal organ defects were observed in any group. These findings do not indicate that toxicity from noni juice to developing embryos and fetuses is expected. PMID:19043286

West, Brett J; Su, Chen X; Jensen, C Jarakae

2008-12-01

136

Comparison of Rapid Toxicity Tests with a Standard Acute Test.  

National Technical Information Service (NTIS)

Rapid bioassays (those requiring less than or equal to 24 hours to complete) including IQ Toxicity Test, MetPLATE, a rotifer test, and Microtox were compared with standard 48-hour Ceriodaphina dubia test when exposed to six different chemicals. Tests that...

S. M. Nelson R. A. Roline

1997-01-01

137

Evaluation of bleached kraft mill process water using Microtox(R), Ceriodaphnia dubia, and Menidia beryllina toxicity tests.  

PubMed

To determine whether a 7- to 10-d embryo toxicity/teratogenicity test with the inland silverside fish, Menidia beryllina, is a sensitive indicator for evaluation of bleached kraft mill effluents, we compared this test with the Microtox(R) 15-min acute toxicity test and the Ceriodaphnia dubia 7-d chronic toxicity test. Water samples used in each test were collected from three areas in a bleached kraft pulp and paper mill using a 100% chlorine dioxide bleaching process: 1) river water prior to use in the mill; 2) the combined acid/base waste stream from the pulping process prior to biological treatment in the aerated stabilization basin (ASB); and 3) the effluent from the ASB with a retention time of approximately 11 d. Relative toxicity determined by the three tests for each water sampling location was compared. All three toxicity tests were predictive indicators of toxicity; however, the C. dubia and M. beryllina tests were the more similar and sensitive indicators of toxicity. Process water (ASB influent) prior to biological treatment in the ASB was toxic at all concentrations using the Microtox(R) and C. dubia tests. The fish embryo test showed no toxicity at 1% concentrations, slight toxicity at 10%, and acute toxicity at the 100% ASB influent concentration. Tests with biologically-treated ASB effluent indicated a substantial reduction in observed toxicity to Microtox(R) bacteria, C. dubia, and M. beryllina. No toxic responses were observed in any test at a 1% ASB effluent concentration which was the approximate effluent concentration in the receiving river following mixing. No relationship was found among any toxicological response and effluent levels of adsorbable organic halides, polychlorinated phenolic compounds, 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, total suspended solids, color, chemical oxygen demand, or total organic carbon. PMID:9175501

Middaugh, D P; Beckham, N; Fournie, J W; Deardorff, T L

1997-05-01

138

Updating Developmental Toxicity Testing Guidelines for the Safety Assessment of Direct Food Additives and Color Additives Used in Food: Results of a Survey  

Microsoft Academic Search

In 1982, the Food and Drug Administration (FDA) issued guidelines for testing the effects of direct food additives and color additives on developing embryos and for longer monitoring during several generations. In 1984, an FDA task force began a review of testing procedures for reproductive and developmental toxicity. The Developmental Toxicity Committee was formed specifically to evaluate the current guidelines

Thomas F. X. Collins; Thomas N. Black; Stuart L. Graham; Benjamin A. Jackson; John J. Welsh

1991-01-01

139

Effects of Specific Dosages of Magnesium and Zinc on the Teratogenicity of Cadmium, Nickel, and Cobalt in Xenopus Embryos, as Assessed by the Fetax Test  

PubMed Central

The objective of this study was to determine if exposure to divalent cations, Cd2+, Ni2+, and Co2+ would lead to malformations in Xenopus laevis embryos, and whether addition of Mg2+ and Zn2+; separately and in combination, would reduce their toxicity and teratogenicity on the embryos of Xenopus laevis as assessed by 96-h FETAX tests. Results indicate that exposure to Cd2+, Ni2+ or Co2+ lead to an increase in toxicity and teratogenicity in embryos, whereas Mg2+, Zn2+, or a combination of them reduced the toxic and terato-genic effects of these divalent cations. Modulation of Cd2+, Ni2+ or Co2+ toxicity and teratogenicity by Mg2+ and Zn2+, varied with the metal. Zn2+ was observed to be a better suppressor of Co2+ toxicity and teratogenicity than Mg2+. In contrast, Ni2+, and Cd2+ teratogenicity was reduced more prominently by Mg2+. On the other hand, combination of Mg2+ and Zn2+ showed potentialization effect on all divalent cation toxicity and teratogenicity. We concluded that Mg2+ and Zn2+ reduced the toxicity and teratogenicity of Cd2+, Ni2+, Co2+.

Boga, Ayper; Erdogan, Seref; Sertdemir, Yasar

2008-01-01

140

Toxicity of petroleum crude oils and their effect on xenobiotic metabolizing enzyme activities in the chicken embryo in ovo  

SciTech Connect

Microliter quantities of a Prudhoe Bay crude oil (PBCO) applied to the shell of fertile chick eggs during various stages of development induced cytochrome P-450 levels and mixed-function oxidase activities within the liver of the embryo. PBCO (5 ..mu..l) applied on Day 11 of incubation was found to maximally induce within 24 hr embryo hepatic cytochrome P-450 levels (fourfold), naphthalene hydroxylase (sixfold), benzo(a)pyrene 3-hyroxylase (14-fold), and 7-ethoxyresorufin O-deethylase (24-fold). Glutathione S-transferase was not induced. Crude oils are known to be highly toxic to avian embryos, especially during the early stages of development. The LD/sub 50/ of PBCO and Hibernia crude oil applied to the egg shell on Day 8 of incubation was found to be 1.3 and 2.2 ..mu..l, respectively. Mixed-function oxidase-dependent metabolism of crude oil components may be required for toxicity since administration of 20 ..mu..g of disulfiram in dioxane 1 hr prior to application of 1.3 ..mu..l of PBCO reduced embryo mortality from 60 to 20%.

Lee, Y.Z.; O'Brien, P.J.; Payne, J.F.; Rahimtula, A.D.

1986-01-01

141

Evaluations of combined zebrafish (Danio rerio) embryo and marine phytoplankton (Diacronema lutheri) toxicity of dissolved organic contaminants in the Ythan catchment, Scotland, UK.  

PubMed

A wide variety of organic contaminants including pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) have previously been detected in surface waters in the river Ythan catchment, North East Scotland UK. While the concentrations detected were below Water Framework Directive Environmental Quality Standards (WFD-EQSs) environmental exposures to the diverse mixtures of contaminants, known and unknown, may pose chronic and/or sublethal effects to non target organisms. The present study assessed the embryo and algal toxicity potential of freely dissolved organic contaminants from the Ythan catchment using silicone rubber passive sampling devices (SR-PSDs) and miniaturised bioassay techniques. Zebrafish (Danio rerio) embryos and marine phytoplankton species (Diacronema lutheri) were exposed to extracts from SR-PSDs deployed at different locations along the river Ythan and an undeployed procedural blank. Statistically significant developmental and algal toxicities were measured in all tests of extracts from deployed samples compared with the procedural blanks. This indicates environmental exposure to, and the combined toxicity potential of, freely dissolved organic contaminants in the catchment. The present and previous studies in the Ythan catchment, coupling SR-PSDs and bioassay techniques, have both helped to understand the interactions and combined effects of dissolved organic contaminants in the catchment. They have further revealed the need for improvement in the techniques currently used to assess environmental impact. PMID:24407789

Emelogu, Emmanuel S; Seiler, Thomas-Benjamin; Pollard, Pat; Robinson, Craig D; Webster, Lynda; McKenzie, Craig; Heger, Sebastian; Hollert, Henner; Bresnan, Eileen; Best, Jennifer; Moffat, Colin F

2014-04-01

142

Toxicity Assessments of Near-infrared Upconversion Luminescent LaF3:Yb,Er in Early Development of Zebrafish Embryos  

PubMed Central

This study reports the effects of upconversion nanoparticles (UCNPs) LaF3:Yb,Er on zebrafish, with the aim of investigating UCNPs toxicity. LaF3:Yb,Er were prepared by an oleic acid/ionic liquid two-phase system, and characterized by transmission electron microscope and X-ray powder diffraction. 140 zebrafish embryos were divided into six test groups and one control group, and respectively were injected into 5, 25, 50, 100, 200, 400 ?g/mL LaF3:Yb,Er@SiO2 solution, and respectively were raised for 5 days. Each experiment was repeated ten times. Results showed that water-soluble LaF3:Yb,Er were successfully prepared, and did not exhibit obvious toxicity to zebrafish embryos under 100 ?g/mL, but exhibited chronic toxicities 200 ?g/mL in vivo, resulting in malformations and delayed hatching rate and embryonic and larval development. The excretion channels of LaF3:Yb,Er in adult zebrafish were mainly found in the intestine after being injected evenly for 24 h. In conclusion, the exploration of LaF3:Yb,Er for in vivo applications in animals and humans must consider UCNPs biocompatibility.

Wang, Kan; Ma, Jiebing; He, Meng; Gao, Guo; Xu, Hao; Sang, Jie; Wang, Yuxia; Zhao, Baoquan; Cui, Daxiang

2013-01-01

143

Modifications of the Topical Japanese Medaka ( Oryzias latipes) Embryo Larval Assay for Assessing Developmental Toxicity of Pentachlorophenol and p, p?Dichlorodiphenyltrichloroethane  

Microsoft Academic Search

One method currently available for investigating developmental toxicity in teleost species is the Japanese medaka embryo larval assay (MELA). In the present study, the MELA was modified to evaluate repeated topical exposures to pentachlorophenol (PCP) and p, p?-dichlorodiphenyltrichloroethane (DDT) and to identify sensitive stages of embryonic development. A single topical exposure using embryos at 48 h postfertilization resulted in a

K. D. Owens; K. N. Baer

2000-01-01

144

Toxic effects of Gymnodinium cf. mikimotoi unsaturated fatty acids to gametes and embryos of the sea urchin Paracentrotus lividus  

Microsoft Academic Search

The toxicity of the main Gymnodinium cf. mikimotoi polyunsaturated fatty acid, has been investigated using the sea urchin gamete and embryo bioassays. The 18:5n3 fatty acid delays or inhibits first cleavage of Paracentrotus lividus eggs and provokes abnormalities in the embryonic development. These effects were compared with those of other polyunsaturated fatty acids, 18:4n3, 20:5n3 and 22:6n3, which are also

Fériel Sellem; Danielle Pesando; Guy Bodennec; Amor El Abed; Jean-Pierre Girard

2000-01-01

145

Embryo Toxicity of 2,3,7,8-Tetrachlorodibenzo- p- Dioxin to the Wood Duck ( Aix sponsa )  

Microsoft Academic Search

We examined the sensitivity of the wood duck (Aix sponsa) embryo to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injecting the toxicant into their eggs. Six groups of wood duck eggs (n = 35 to 211 per trial) were injected with 0 to 4600 pg TCDD\\/g egg between 2003 and 2005. Injections were made into yolk prior\\u000a to incubation, and eggs were subsequently incubated and assessed weekly

T. P. Augspurger; D. E. Tillitt; S. J. Bursian; S. D. Fitzgerald; D. E. Hinton; R. T. Di Giulio

2008-01-01

146

Selection and application of a rainbow trout toxicity testing procedure for screening Sacramento River Watershed, California samples.  

PubMed

A number of procedures have been developed to assess toxic effects on the early life stages of salmonid fish. In this study 13 rainbow trout embryo development relatively short-term (7 to 90 day) procedures were reviewed. Three 7-day methods from the published literature and three modifications developed at AQUA-Science (A-S) were evaluated in the laboratory. Based on that evaluation, A-S methods were selected for screening surface water samples (A-S 1) collected in the Sacramento River watershed (California) and for conducting toxicity identification evaluations (TIE) to identify cause(s) of toxicity. Test control performance, test sensitivity, and reference toxicant response variability in the A-S 1 were superior to those in commonly used freshwater toxicity testing methods. The incidence of Sacramento River watershed samples resulting in a notable decrease in embryo development was very low. Of 260 samples screened only 16 (6%) resulted in statistically significant inhibition of embryo development. Of the 16 toxic samples, nine caused minimal (less than 20% abnormal development) and four marginal (less than 30%) toxicity. Samples collected from the agriculture-dominated Colusa Basin Drain and rangeland/forest-dominated Battle Creek on June 16, 2005 caused significant toxicity. TIE procedures indicated that cationic chemicals were the primary cause of toxicity. Metals analysis did not reveal concentrations sufficient to inhibit embryo development, so the most probable cause of toxicity in the two samples was cationic chemicals (perhaps surfactants?) or metals that were not included in the analytical screening. PMID:18483874

Miller, Jeffrey L; Miller, Michael J; de Vlaming, Victor; Larsen, Karen; Smith, Edward; Reece, Kevin

2009-03-01

147

Toxicity of polychlorinated diphenyl ethers in hydra attenuata and in rat whole-embryo culture. Master's thesis  

SciTech Connect

Polychlorinated diphenyl ethers (PCDEs) are a class of biaryl compounds that have little commercial application, but appear to be widespread in the environment. They have been found in wood preservative waste dumpsites and in fly ash from municipal waste incinerators. They have been detected in bird eggs and tissues, fish, and other edible marine organisms in the United States, Canada, and Europe. There are limited reports in the extant literature on the toxicity of PCDEs. This study was designed to evaluate the toxicity of selected PCDEs in cultures of Hydra attenuata and post-implantation rat whole embryos. The toxicity of several closely related polychlorinated biphenyls (PCBs) was evaluated in both cultures and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was evaluated in whole embryo culture. Embryonic growth and development parameters (yolk sac diameter, crown-rump length, somite count, and DNA and protein content) and gross morphology were determined. Findings indicated that these chemicals were neither embryotoxic nor teratogenic. Thus, the PCDEs, which elicit other diverse toxic and biochemical responses in rodents, are relatively inactive in these bioassays for developmental toxicity.

Becker, M.C.

1991-05-01

148

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

EPA Science Inventory

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....

149

Toxicity assessment of sediments from three European river basins using a sediment contact test battery.  

PubMed

The toxicity of four polluted sediments and their corresponding reference sediments from three European river basins were investigated using a battery of six sediment contact tests representing three different trophic levels. The tests included were chronic tests with the oligochaete Lumbriculus variegatus, the nematode Caenorhabditis elegans and the mudsnail Potamopyrgus antipodarum, a sub-chronic test with the midge Chironomus riparius, an early life stage test with the zebra fish Danio rerio, and an acute test with the luminescent bacterium Vibrio fischeri. The endpoints, namely survival, growth, reproduction, embryo development and light inhibition, differed between tests. The measured effects were compared to sediment contamination translated into toxic units (TU) on the basis of acute toxicity to Daphnia magna and Pimephales promelas, and multi-substance Potentially Affected Fractions of species (msPAF) as an estimate for expected community effects. The test battery could clearly detect toxicity of the polluted sediments with test-specific responses to the different sediments. The msPAF and TU-based toxicity estimations confirmed the results of the biotests by predicting a higher toxic risk for the polluted sediments compared to the corresponding reference sediments, but partly having a different emphasis from the biotests. The results demonstrate differences in the sensitivities of species and emphasize the need for data on multiple species, when estimating the effects of sediment pollution on the benthic community. PMID:20833427

Tuikka, A I; Schmitt, C; Höss, S; Bandow, N; von der Ohe, P C; de Zwart, D; de Deckere, E; Streck, G; Mothes, S; van Hattum, B; Kocan, A; Brix, R; Brack, W; Barceló, D; Sormunen, A J; Kukkonen, J V K

2011-01-01

150

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 true Gammarid acute toxicity test. 795.120 Section 795.120 Protection...CONTROL ACT (CONTINUED) PROVISIONAL TEST GUIDELINES Provisional Environmental... § 795.120 Gammarid acute toxicity test. (a) Purpose. This...

2010-07-01

151

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Gammarid acute toxicity test. 795.120 Section 795.120 Protection...CONTROL ACT (CONTINUED) PROVISIONAL TEST GUIDELINES Provisional Environmental... § 795.120 Gammarid acute toxicity test. (a) Purpose. This...

2009-07-01

152

Toxicity potential of absorbed-retained ethylene oxide residues in culture dishes on embryo development in vitro.  

PubMed

Four hundred eight-cell mouse embryos were cultured in vitro in either polystyrene (plastic) dishes (Exp. 1) or watch glasses (Exp. 2) to analyze the toxicity potential of absorbed-retained ethylene oxide (EtO). Culture dishes were gas-sterilized with Anprolene equipment and allowed to aerate (21 C) for varying durations. Post-sterilization EtO residues, as determined by weight measurement, were eluted from polystyrene dishes at an exponential rate. After 1 wk of aeration, .625 mg EtO was retained/g of polystyrene product. To determine the effect of EtO residue on in vitro culture, embryos were collected from superovulated donor mice (C57BL/6N), pooled in a modified Dulbecco's phosphate buffered saline (PBI) medium and then randomly allotted to dishes subjected to various aeration durations. Embryos were cultured in Whitten's medium +3 mg/ml bovine serum albumin (BSA) under a humidified 5% CO2 in air atmosphere at 37 C. Gross assessments of embryo development were made using standard morphology and quality grading systems and a fluorescein diacetate staining assay. In Exp. 1, embryo development was retarded at the 8- to 16-cell stage when less than or equal to 12 h aeration of polystyrene dishes was permitted. Aeration for 24 and 36 h resulted in suboptimal embryo development with fewer (P less than .01) blastocysts and greater degeneration rates at 48 h of in vitro culture compared with the control (manufacturer-packaged dishes, no EtO) and 1-wk aeration treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4019348

Schiewe, M C; Schmidt, P M; Bush, M; Wildt, D E

1985-06-01

153

Assessment of the bioavailability and toxicity of sediment-associated polycyclic aromatic hydrocarbons and heavy metals applied to Crassostrea gigas embryos and larvae.  

PubMed

Sediments represent a vast sink for contaminants in aquatic systems, and may pose a threat to pelagic and benthic organisms. The objective of this research was to determine the bioavailability and toxicity of sediment-associated PAHs and heavy metals, using embryos and larvae of the oyster Crassostrea gigas, exposed to two sediment fractions: the whole sediment and the elutriate. The percentages of abnormal larvae, the contaminant accumulation and, (in the case of metal contamination), the induction of metallothionein in the larvae, were investigated. Sediment-associated PAHs and heavy metals were available for exposure, as indicated by their accumulation in C. gigas larvae and by the abnormalities induced during larval development. The critical body burden of PAHs (Fluo, Pyr, BaA, Triph, Chrys, BbF, BkF, BjK, BeP, BaP, Per, IP, BPer and the DahA) in the larvae was 0.3 micro g g(-1), above which abnormalities were observed. This value corresponds to concentrations observed for most vertebrate and invertebrate species. The bioavailability of PAHs is determined by their solubility; only the soluble fraction of PAHs is accumulated by the embryos. The bioavailability of metals for the larvae is substantiated by MT induction, correlated with cytosolic metal concentrations. MT induction provided a better early-warning response than the embryotoxicity test currently used for evaluating environmental contamination by metals. This study recommends choosing oyster embryos as a particularly sensitive tool for evaluating sediment quality. PMID:12705922

Geffard, O; Geffard, A; His, E; Budzinski, H

2003-04-01

154

MAMMALIAN WILDLIFE (MINK AND FERRET) TOXICITY TEST PROTOCOLS (LC50, REPRODUCTION, AND SECONDARY TOXICITY)  

EPA Science Inventory

Protocols describing guidelines for conducting dietary LC50 and reproduction toxicity tests and for assessing the primary versus secondary toxicity of a test substance using carnivorous mammalian wildlife, specifically mink (Mustela vison) or European ferrets (Mustela putorius fu...

155

CHIRONOMIDAE TOXICITY TESTS--BIOLOGICAL BACKGROUND AND PROCEDURES  

EPA Science Inventory

Toxicity tests must be based on an understanding of the test animal's life cycle. The first section of this report describes the biological information needed to develop toxicity test procedures. The second section describes three categories of toxicity test systems - short-expos...

156

Ocular Toxicity Testing of Lunar Dust  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the use of ocular testing to determine the toxicity of lunar dust. The OECD recommendations are reviewed. With these recommendations in mind the test methodology was to use EpiOcular, tissues derived from normal human epidermal keratinocytes, the cells of which have been differentiated on cell culture inserts to form a multi-layered structure, which closely parallels the corneal epithelium and to dose the tissue with 100 mg dust from various sources. The in-vitro study provides evidence that lunar dust is not severely corrosive or irritating, however, in vitro tests have limitations, and in vivo tests provides a more complete scenario, and information, it is recommended that in vivo tests be performed.

Meyers, Valerie E.

2010-01-01

157

Morphological development of testes in ostrich (Struthio camelus) embryo.  

PubMed

Although the histological structure of ostrich testis has been studied, very little information is currently available on the embryonic development of this organ. The aim of this study was to determine the sequence of the histological changes in diverse components of the testis in ostrich embryo from embryonic day (E) 20 to E42. The main findings were categorized into four histological features, i.e., development of sex cords, interstitial tissue and rete ducts, and the appearance of defective septa. While the lumen of sex cords, tunica albuginea, capsular rete ducts and Leydig cell precursors appeared at E26, the filum-shaped defective septa were visible at E36. The emersion of the lumen in the primary sex cords and formation of capsular rete ducts in the ostrich embryo is considerably different from that in other birds. However, tunica albuginea and Leydig cell precursors appeared in a similar pattern to those of other birds. An interesting observation was that the primordial germ cell (PGC)-like cells were completely distinct, while the capsular rete ducts were formed by trapping of some Sertoli cell aggregations in the tunica albuginea. This suggests that similar to the primary sex cords, the capsular rete ducts may originate from the Sertoli cell aggregations which had corralled some PGCs. Stereological estimations in the ostrich embryo testis showed the major proportion of testis is occupied by the seminiferous tubules, which is unlike the fowl embryo testis. PMID:24127229

Hassanzadeh, Belal; Nabipour, Abolghasem; Behnam Rassouli, Morteza; Dehghani, Hesam

2014-06-01

158

Teratogenic and toxic effects of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.:Fr.) P. Karst. (higher Basidiomycetes), on zebrafish embryo as model.  

PubMed

This paper highlights the teratogenic and toxic effects of Ganoderma lucidum (Lingzhi or Reishi mushroom) extract on zebrafish embryos. Hatchability, malformations, and lethality rate of zebrafish embryos were assessed to provide valuable information regarding the potential teratogenic activity of G. lucidum. Hatching was completed 48 h post treatment application (hpta) at 1% or lower concentrations of extract and embryo water. The hatching rate of embryos treated with 5% or higher concentrations was significantly lower (p> 0.05) than the control. Tail malformation was the most marked morphological abnormality in embryos at 72 hpta, which was obviously caused by 1% extract (55.56% tail malformation) and was observed in all embryos exposed to 5% of extract. Growth retardation was evident in embryos exposed to 5%, 10%, and 20%. However, lethal effect of extract of G. lucidum was dependent on dose and time of exposure. Mortality rates of embryos treated with 5% (44.44%) or higher concentrations of the extract was significantly higher (p > 0.05) than that of the control embryos at 72 hpta. These results suggest that G. lucidum extract has lethal and sub-lethal effects on zebrafish embryos. PMID:23510220

Dulay, Rich Milton R; Kalaw, Sofronio P; Reyes, Renato G; Alfonso, Noel F; Eguchi, Fumio

2012-01-01

159

A new screening test for toxicity testing of dental materials  

Microsoft Academic Search

Objectives: The development of a micro plate assay for cytotoxicity testing of dental materials based on a bioassay using brine shrimp larvae (artemia salina) as sensitive organisms.Methods: Brine shrimp larvae are commonly used for cytotoxicity assays in pharmacology. These larvae are sensitive to toxic substances. The ratio between dead larvae (no motility) and living larvae (high motility) in comparison to

M Pelka; C Danzl; W Distler; A Petschelt

2000-01-01

160

The Red Tide Toxin, Brevetoxin, Induces Embryo Toxicity and Developmental Abnormalities  

NSDL National Science Digital Library

This Environmental Health Perspectives journal article documents a study on the relationship between brevetoxin, a toxin produced by red tide-related dinoflagellates, and abnormalities in fish embryos. The article features color photographs, charts, and tables.

Kimm-Brinson, Karen L.; Ramsdell, John S.; Perspectives, Environmental H.

161

TOXICITY OF GUTHION AND GUTHION 2S TO XENOPUS LAEVIS EMBRYOS  

EPA Science Inventory

Differences in sensitivity to waterborne contaminants between wildlife species have prompted investigations on the sensitivity of amphibians to potentially hazardous environmental chemicals. he development of Xenopus laevis (African clawed frog) embryos exposed to the pesticide G...

162

Toxicity of Guthion (Trade Name) and Guthion (Trade Name) 2S to 'Xenopus laevis' Embryos.  

National Technical Information Service (NTIS)

Differences in sensitivity to waterborne contaminants between wildlife species have prompted investigations on the sensitivity of amphibiams to potentially hazardous environmental chemicals. The development of Xenopus laevis (African clawed frog) embryos ...

G. S. Schuytema A. V. Nebeker W. L. Griffis

1994-01-01

163

In vitro models for liver toxicity testing  

PubMed Central

Over the years, various liver-derived in vitro model systems have been developed to enable investigation of the potential adverse effects of chemicals and drugs. Liver tissue slices, isolated microsomes, perfused liver, immortalized cell lines, and primary hepatocytes have been used extensively. Immortalized cell lines and primary isolated liver cells are currently most widely used in vitro models for liver toxicity testing. Limited throughput, loss of viability, and decreases in liver-specific functionality and gene expression are common shortcomings of these models. Recent developments in the field of in vitro hepatotoxicity include three-dimensional tissue constructs and bioartificial livers, co-cultures of various cell types with hepatocytes, and differentiation of stem cells into hepatic lineage-like cells. In an attempt to provide a more physiological environment for cultured liver cells, some of the novel cell culture systems incorporate fluid flow, micro-circulation, and other forms of organotypic microenvironments. Co-cultures aim to preserve liver-specific morphology and functionality beyond those provided by cultures of pure parenchymal cells. Stem cells, both embryonic- and adult tissue-derived, may provide a limitless supply of hepatocytes from multiple individuals to improve reproducibility and enable testing of the individual-specific toxicity. This review describes various traditional and novel in vitro liver models and provides a perspective on the challenges and opportunities afforded by each individual test system.

Soldatow, Valerie Y.; LeCluyse, Edward L.; Griffith, Linda G.; Rusyn, Ivan

2013-01-01

164

TOXICITY TESTS FOR SEDIMENT QUALITY ASSESSMENTS  

EPA Science Inventory

Toxic sediments have contributed to a wide-variety of environmental problems around the world. The observed effects include direct toxic effects to aquatic life, bio-magnification of toxicants in the food chain, and economic impacts. This chapter discusses the use of toxicity...

165

Integrated chip-based physiometer for automated fish embryo toxicity biotests in pharmaceutical screening and ecotoxicology.  

PubMed

Transgenic zebrafish (Danio rerio) models of human diseases have recently emerged as innovative experimental systems in drug discovery and molecular pathology. None of the currently available technologies, however, allow for automated immobilization and treatment of large numbers of spatially encoded transgenic embryos during real-time developmental analysis. This work describes the proof-of-concept design and validation of an integrated 3D microfluidic chip-based system fabricated directly in the poly(methyl methacrylate) transparent thermoplastic using infrared laser micromachining. At its core, the device utilizes an array of 3D micromechanical traps to actively capture and immobilize single embryos using a low-pressure suction. It also features built-in piezoelectric microdiaphragm pumps, embryo-trapping suction manifold, drug delivery manifold, and optically transparent indium tin oxide heating element to provide optimal temperature during embryo development. Furthermore, we present design of the proof-of-concept off-chip electronic interface equipped with robotic servo actuator driven stage, innovative servomotor-actuated pinch valves, and embedded miniaturized fluorescent USB microscope. Our results showed that the innovative device has 100% embryo-trapping efficiency while supporting normal embryo development for up to 72 hr in a confined microfluidic environment. We also showed data that this microfluidic system can be readily applied to kinetic analysis of a panel of investigational antiangiogenic agents in transgenic zebrafish lines. The optical transparency and embryo immobilization allow for convenient visualization of developing vasculature patterns in response to drug treatment without the need for specimen re-positioning. The integrated electronic interfaces bring the lab-on-a-chip systems a step closer to realization of complete analytical automation. © 2014 International Society for Advancement of Cytometry. PMID:24664821

Akagi, Jin; Zhu, Feng; Hall, Chris J; Crosier, Kathryn E; Crosier, Philip S; Wlodkowic, Donald

2014-06-01

166

Exposure Science for Chemical Prioritization and Toxicity Testing  

EPA Science Inventory

Currently, a significant research effort is underway to apply new technologies to screen and prioritize chemicals for toxicity testing as well as to improve understanding of toxicity pathways (Dix et al. 2007, Toxicol Sci; NRC, 2007, Toxicity Testing in the 21st Century; Collins ...

167

The red tide toxin, brevetoxin, induces embryo toxicity and developmental abnormalities.  

PubMed Central

Brevetoxins are lipophilic polyether toxins produced by the red tide dinoflagellate Gymnodinium breve, and their neurotoxic effects on adult animals have been documented. In this study, we characterized adverse developmental effects of brevetoxin-1 (PbTx-1) using an exposure paradigm that parallels the maternal oocyte transfer of toxin. Medaka fish (Oryzias latipes) embryos were exposed to PbTx-1 via microinjection of toxin reconstituted in a triolein oil droplet. Embryos microinjected with doses of 0.1-8.0 ng/egg (ppm) of brevetoxin-1 exhibited pronounced muscular activity (hyperkinesis) after embryonic day 4. Upon hatching, morphologic abnormalities were commonly found in embryos at the following lowest adverse effect levels: 1.0-3.0 ppm, lateral curvature of the spinal column; 3.1-3.4 ppm, herniation of brain meninges through defects in the skull; and 3.4-4.0 ppm, malpositioned eye. Hatching abnormalities were also commonly observed at brevetoxin doses of 2.0 ppm and higher with head-first, as opposed to the normal tail-first, hatching, and doses > 4.1 ng/egg produced embryos that developed but failed to hatch. Given the similarity of developmental processes found between higher and lower vertebrates, teratogenic effects of brevetoxins have the potential to occur among different phylogenetic classes. The observation of developmental abnormalities after PbTx-1 exposure identifies a new spectrum of adverse effects that may be expected to occur following exposure to G. breve red tide events.

Kimm-Brinson, K L; Ramsdell, J S

2001-01-01

168

The effects of salinity on copper and silver toxicity to embryos of the Pacific Oyster  

Microsoft Academic Search

Embryonic development of the Pacific oyster was monitored under various combinations of copper × salinity and silver × salinity. Oyster embryos were exposed to salinities between 14.5 and 33 %, copper concentrations between 0 to 10 ppb and silver concentrations between 0 to 18 ppb. Exposure to salinities between 22.7 and 33 % had no significant effect on normal embryonic

Matthew P. Coglianese

1982-01-01

169

THE USE OF EMBRYOS OF PALAEMONETES PUGIO IN EVALUATING THE DEVELOPMENTAL TOXICITY OF COMPOUNDS  

EPA Science Inventory

The grass shrimp, Palaemonetes pugio, is a common, well distributed species along the eastern coast of America that is an important part of the food web. The embryos of P. pugio have shown sensitivity to the water-soluble fraction of Number 2 fuel oil, which indicates they may be...

170

The Bioaccumulation and Toxicity of Platinum Group Metals in Developing Chick Embryos  

Microsoft Academic Search

Recent studies showed that platinum group metals (PGMs) such as Pt, Pd, and Rh from automobile catalytic converters, can accumulate in the soft tissues of a variety of living organisms. However, the effects of PGMs on bone and organs development of animals are not clearly understood. To examine these aspects, developing chick embryos were injected with 0.1, 1.0, 5, or

Ioana Pavel; Jennifer Monahan; Marjorie Markopoulos; Zofia Gagnon; Britney Nejame; Jacob Cawley; David Reens

2008-01-01

171

A dietary embryo/fetal developmental toxicity study of arruva, an R,R-monatin salt isomer, in Crl:CD(SD) rats.  

PubMed

R,R-Monatin is an intensely sweet substance originally identified in the root bark of Sclerochiton ilicifolius. R,R-Monatin salt, commonly known as "arruva", has potential for use as a high-potency sweetener food ingredient. Previously, arruva was concluded to present no toxicologically relevant effects to Crl:CD(SD) rats and Crl:CD-1(ICR) mice fed up to 35,000 ppm arruva in the diet for 90 days. In the present study, groups of mated Sprague-Dawley rats (25 Crl:CD(SD) females/group) were exposed continuously to 0 (control), 15,000, 30,000, or 50,000 ppm arruva in the diet during gestation days 6-21. There were no fetal malformations or developmental variations that were attributable to arruva at any exposure level, nor were there any test article-related effects on intrauterine survival. Maternal toxicity, evidenced by lower mean body weights, body weight gains and feed efficiency, was observed at 50,000 ppm. A developmental effect, in the form of lower mean fetal body weight, was noted in the 50,000 ppm group in the presence of maternal toxicity. Therefore, the dietary no-observed-adverse-effect level (NOAEL) for maternal and embryo/fetal developmental toxicity of arruva in pregnant rats during gestation days 6-21 was 30,000 ppm (equivalent to 2564 mg/kg bw/day) based on reductions in maternal and fetal body weights. PMID:23973404

Brathwaite, W A; Casterton, P L; Nikiforov, A I; Rihner, M O; Sloter, E D; Hlywka, J J

2013-12-01

172

Effect of pH on pentachlorophenol toxicity to embryos and larvae of zebrafish (Brachydanio rerio)  

SciTech Connect

The hydrogen ion is an important determinant of toxicity in the aquatic environment, especially for weak acids or bases. Pentachlorophenol is a weak acid and is consequently more toxic at low pH because of increasing proportions of free phenol. For some heavy metals the toxic interaction with ambient pH is complicated by complexation with organic and inorganic compounds. These complexes are affected by pH, and bioassays may be the easiest and most reliable method of determining the influence of pH in such cases. The objective of this study was to find a simple laboratory procedure for determination of the effect of pH on the toxicity of various chemicals added to or already present in various samples of ground and surface waters. Pentachlorophenol was selected as a reference toxicant and positive control because of its established pH-toxicity interaction in fish.

Dave, G.

1984-11-01

173

Sand spiked with copper as a reference toxicant material for sediment toxicity testing: A preliminary evaluation  

SciTech Connect

Routine use of solid-phase sediment toxicity tests for scientific and regulatory purposes necessitates the development of solid-phase reference toxicant materials. In order to evaluate an approach for developing such materials, 12 solid-phase 96-h reference toxicant tests were conducted over 12 weeks with the marine bivalve Mulinia lateralis. Measured concentrations of copper in the water column above the reference material during testing showed that the toxicant exposures were relatively consistent between tests. Coefficients of variation (CV) for mortality and sublethality (growth) endpoints were 39% and 42%, respectively. (Copyright (c) 1994 Springer-Verlag New York Inc.)

Burgess, R.M.; Rogers, B.A.; Rego, S.A.; Corbin, J.M.; Morrison, G.E.

1994-01-01

174

The Red Tide Toxin, Brevetoxin, Induces Embryo Toxicity and Developmental Abnormalities  

Microsoft Academic Search

Brevetoxins are lipophilic polyether toxins produced by the red tide dinoflagellate Gymnodinium breve, and their neurotoxic effects on adult animals have been documented. In this study, we characterized adverse developmental effects of brevetoxin-1 (PbTx-1) using an exposure paradigm that parallels the maternal oocyte transfer of toxin. Medaka fish (Oryzias latipes) embryos were exposed to PbTx-1 via microinjection of toxin reconstituted

Karen L. Kimm-Brinson; John S. Ramsdell

175

Toxicity to medaka fish embryo development of okadaic acid and crude extracts of Prorocentrum dinoflagellates  

Microsoft Academic Search

Chronic and subchronic toxicity following exposure to the DSP (Diarrhetic shellfish poisoning) toxin okadaic acid (OA) is receiving increasing attention as a public human health biohazard. However information on ecological impacts induced by proliferation of the OA producing dinoflagellate Prorocentrum is scarce. In order to analyse the toxicity of these substances, in vivo experiments were conducted on medaka fish (Oryzias

Nicolas Escoffier; Julien Gaudin; Karim Mezhoud; Hélène Huet; Sophie Chateau-Joubert; Jean Turquet; François Crespeau; Marc Edery

2007-01-01

176

Comparison of ethanol toxicity to Daphnia magna and Ceriodaphnia dubia tested at two different temperatures: Static acute toxicity test results  

Microsoft Academic Search

Ethanol is a commonly used solvent in toxicity testing, yet there are few studies in the literature devoted to its toxicity to zooplankton. The purpose of this study was to compare the response of Daphnia magna Straus 1820 and Ceriodaphnia dubia J. Richard 1894 to ethanol. Two temperatures were selected because most toxicity data involving D. magna has been carried

I. T. Takahashi; U. M. Cowgill; P. G. Murphy

1987-01-01

177

Toxicity assessment of dye containing industrial effluents by acute toxicity test using Daphnia magna.  

PubMed

Toxicity of dye containing effluent of tannery, textile, dyes and pulp-paper industries was evaluated in an acute toxicity test using Daphnia magna. The 48-hour EC(50) values were 4.33% and 19.5% for tannery effluents (Tn1 and Tn2). Textile effluents (Tx1-Tx7) had 48-hour EC(50) values; >100%, >100%, 62.9%, 63.0%, 40.3%, >100% and >100%, respectively. Dye industries (D1-D7) had 48-hour EC(50) values; 14.1%, 15.5%, 24.5%, 29.7%, 23.2%, >100% and >100%, respectively. Similarly pulp-paper effluents (P1-P5) showed acute toxicity as 100%, 77.87%, 46.44%, 69.55% and 82.84%, respectively. These results showed linear relationship with high degree of confidence (r(2) ? 0.84-0.99) between immobility and test concentrations. Toxicity classification criteria showed that out of five effluents from pulp-paper mill, four were minor acutely toxic having 48-hour EC(50) value in between >46%-100%. Out of seven textile effluents, four were not acutely toxic (48-hour EC(50) value >100%) and three were minor acutely toxic (48-hour EC( 50) value in the range of 40.3%-63.0%). Similarly, out of seven dye industrial effluents, two were not acutely toxic and five minor acutely toxic. One of the two tanneries was moderately acutely toxic and another one was minor acutely toxic. Classification based on toxic unit revealed that four out of five pulp-paper effluent, three out of seven textile effluents, five out of seven dye effluents and both the tannery effluents were toxic. Overall, 66.67% effluents were found toxic and 33.33% as non-toxic. In general, tannery and dyes effluents showed more toxicity than textile and paper mill effluents. PMID:20823054

Verma, Yogendra

2011-02-01

178

Selenoneine, a novel selenium-containing compound, mediates detoxification mechanisms against methylmercury accumulation and toxicity in zebrafish embryo.  

PubMed

The selenium (Se)-containing antioxidant selenoneine (2-selenyl-N ?,N ?,N ?-trimethyl-L-histidine) has recently been discovered to be the predominant form of organic Se in tuna blood. Although dietary intake of fish Se has been suggested to reduce methylmercury (MeHg) toxicity, the molecular mechanism of MeHg detoxification by Se has not yet been determined. Here, we report evidence that selenoneine accelerates the excretion and demethylation of MeHg, mediated by a selenoneine-specific transporter, organic cations/carnitine transporter-1 (OCTN1). Selenoneine was incorporated into human embryonic kidney HEK293 cells transiently overexpressing OCTN1 and zebrafish blood cells by OCTN1. The K m for selenoneine uptake was 13.0 ?M in OCTN1-overexpressing HEK293 cells and 9.5 ?M in zebrafish blood cells, indicating high affinity of OCTN1 for selenoneine in human and zebrafish cells. When such OCTN1-expressing cells and embryos were exposed to MeHg-cysteine (MeHgCys), MeHg accumulation was decreased and the excretion and demethylation of MeHg were enhanced by selenoneine. In addition, exosomal secretion vesicles were detected in the culture water of embryos that had been microinjected with MeHgCys, suggesting that these may be responsible for MeHg excretion and demethylation. In contrast, OCTN1-deficient embryos accumulated MeHg, and MeHg excretion and demethylation were decreased. Furthermore, Hg accumulation was decreased in OCTN1-overexpressing HEK293 cells, but not in mock vector-transfected cells, indicating that selenoneine and OCTN1 can regulate MeHg detoxification in human cells. Thus, the selenoneine-mediated OCTN1 system regulates secretory lysosomal vesicle formation and MeHg demethylation. PMID:23709046

Yamashita, Michiaki; Yamashita, Yumiko; Suzuki, Tamami; Kani, Yoko; Mizusawa, Nanami; Imamura, Shintaro; Takemoto, Kenji; Hara, Tatsuro; Hossain, Md Anwar; Yabu, Takeshi; Touhata, Ken

2013-10-01

179

A Simple "in Vitro" Culture of Freshwater Prawn Embryos for Laboratory Investigations  

ERIC Educational Resources Information Center

Giant freshwater prawn ("Macrobrachium rosenbergii" De Man) embryos can be cultured "in vitro" to hatching in 15% (v/v) artificial seawater (ASW). This technique can be applied as a bioassay for testing toxicity or for the effects of various substances on embryo development and can be used as a simple and low-cost model for studying embryo

Porntrai, Supaporn; Damrongphol, Praneet

2008-01-01

180

Toxicity testing of trinitrotoluene-contaminated soil composts  

SciTech Connect

The Mutatox{trademark} assay and earthworm acute toxicity test were employed to evaluate the efficacy of composting in reducing the toxicity of TNT-contaminated soils. The Mutatox assay is a proprietary bacterial bioluminescence test that determines the mutagenic potential of sample extracts. The earthworm acute toxicity test was chosen because it exposes the organisms to the unaltered contaminant/solid matrix. Rockeye soil, a TNT-contaminated soil collected from a military installation, was composted using two methods. This yielded five samples, Rockeye, Compost A composting. Soil extracts were prepared for Mutatox using the sonification method. Ten serial dilution samples were tested soils/artificial soil were tested in the earthworm toxicity test. In the Rockeye soil samples, a toxic response was shown in both test methods. Mutatox indicated no toxicity in Composts A and B after composting but did not show a positive mutagenic response in the lower serial dilutions. The LC50s for Compost A and B after composting in the earthworm toxicity test were 35.3% and 100%, respectively. Using Mutatox and the earthworm toxicity test together provides a sensitive means of monitoring the effectiveness of various composting techniques for remediating TNT-contaminated soils.

Honeycutt, M.E. [TNRCC TARA, Austin, TX (United States); McFarland, V.A.; Jarvis, A.S. [USAEWES, Vicksburg, MS (United States)

1997-10-01

181

Integrated decision-tree testing strategies for environmental toxicity with respect to the requirements of the EU REACH legislation.  

PubMed

Liverpool John Moores University and FRAME recently conducted a research project sponsored by Defra on the status of alternatives to animal testing with regard to the European Union REACH (Registration, Evaluation and Authorisation of Chemicals) system for safety testing and risk assessment of chemicals. The project covered all the main toxicity endpoints associated with the REACH system. This paper focuses on the prospects for using alternative methods (both in vitro and in silico) for environmental (aquatic) toxicity testing. The manuscript reviews tests based on fish cells and cell lines, fish embryos, lower organisms, and the many expert systems and QSARs for aquatic toxicity testing. Ways in which reduction and refinement measures can be used are also discussed, including the Upper Threshold Concentration -- Step Down (UTC) approach, which has recently been retrospectively validated by ECVAM and subsequently endorsed by the ECVAM Scientific Advisory Committee (ESAC). It is hoped that the application of this approach could reduce the number of fish used in acute toxicity studies by around 65-70%. Decision-tree style integrated testing strategies are also proposed for acute aquatic toxicity and chronic toxicity (including bioaccumulation), followed by a number of recommendations for the future facilitation of aquatic toxicity testing with respect to environmental risk assessment. PMID:17266395

Grindon, Christina; Combes, Robert; Cronin, Mark T D; Roberts, David W; Garrod, John

2006-12-01

182

Biologically Relevant Exposure Science for 21st Century Toxicity Testing  

EPA Science Inventory

High visibility efforts in toxicity testing and computational toxicology including the recent NRC report, Toxicity Testing in the 21st Century: a Vision and Strategy (NRC, 2007), raise important research questions and opportunities for the field of exposure science. The authors ...

183

Toxicity Testing for Human Health Risk Assessment  

Microsoft Academic Search

Research into the toxic effects of substances on humans can be traced back to the ancient centres of civilization in Egypt,\\u000a Greece and China, where toxic chemical substances were used as poisons and sometimes as medicines. “Toxicology is the scientific\\u000a discipline involving the study of actual or potential danger presented by the harmful effects of substances in living organisms\\u000a and

T. G. Vermeire; A. J. Baars; J. G. M. Bessems; B. J. Blaauboer; W. Slob; J. J. A. Muller

184

Temperature-based rapid toxicity test using Ceriodaphnia dubia.  

PubMed

Toxicants, which may cause the inhibition to the biological process in sewage/wastewater treatment plant, need to be monitored within short time to prevent from serious damage. A new method, Temperature-based rapid toxicity test (TempTox test) using Ceriodaphnia dubia, was developed and compared with the standard 48 hr acute bioassay (Std. 48-hr test). Inorganic toxicants of cadmium, zinc, copper, cyanide, chromium (III), chromium (VI) and organic toxicants of phenol, PCP and pesticides of BPMC, Diazinon, Fenitrothion were tested for TempTox test and Std. 48-hr test. Because the TempTox test is based on just temperature control, C. dubia neonates were exposed to toxicants under high temperature (35.5 degrees C) condition without any complicated pretreatment. After given exposure time of 1, 1.25, 1.5 hours, the number of the live (no toxic effect) or the dead (toxic effect) was counted with eye without the aid of any microscope and median effective concentrations (EC50 values) were determined. From the results for all toxicants, the TempTox test was proved to be as sensitive as the Std. 48-hr test with shorter-time of just 1.25-1.5 hours. Moreover, the TempTox test was further much more sensitive than alternative bioassays such as the 1-hour l.Q. test and 30-minute Microtox. The TempTox test showed a high applicability of toxicity bioassay for real sewage/wastewater treatment plant by its easiness, rapidity and sensitivity. Finally, the prototype for short-term TempTox test was introduced. PMID:16722086

Jun, B H; Lee, S I; Ryu, H D; Kim, Y J

2006-01-01

185

Bioaccumulation and toxicity of four dissolved metals in Paracentrotus lividus sea-urchin embryo  

Microsoft Academic Search

The bioaccumulation of four metals (Cd, Cu, Pb, Zn) dissolved in water was assessed measuring the concentrations recorded within sea-urchin larvae (Paracentrotus lividus, Lmk.) after a 48-h exposure period. Concurrently, the frequencies of abnormalities were evaluated at the 48-h pluteus stage to check the actual toxicity of such contaminants with regards to larval development. Maximum metal concentrations in the larvae

G. Radenac; D. Fichet; P. Miramand

2001-01-01

186

Toxicity Tests for Ensuring Succesful Industrial Wastewater Treatment Plant Operation  

NASA Astrophysics Data System (ADS)

Industrial wastewaters are complex and can be polluted by non-biodegradable end toxic organic compounds and are a serious threat to the environment. Chemical procedure alone cannot provide sufficient information. A complete evaluation of wastewaters should include ecotoxicological tests too, especially concerning the complex wastewaters. In the literature review the authors attempted to establish which is the more promising and suitable aquatic toxicology test for sewage treatment plant influent toxicity monitoring. A variety of types of organisms representing different trophic levels and many different species are used for aquatic toxicity testing. Toxicity characterization would be needed both for influents and effluents of wastewater treatment plant. For the purpose of screening biological wastewater treatment influent, toxicity to activated sludge microorganisms is important and toxicology tests here used are respirometry and bioluminescence toxicology tests. Respirometry toxicity tests are easy, fast and inexpensive compared to other approaches. Bioluminescence has been widely used, the most thoroughly investigated test system is the Microtox. The toxicity tests have also been compared by different authors. International, national and regional authorities use these tools to meet various regulatory and legislative requirements. Importance of biotesting has been emphasized also in EU legislation.

C?bere, B.; Falti?a, E.; Zel??ns, N.; Kalni?a, D.

2009-01-01

187

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

EPA Science Inventory

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

188

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

EPA Science Inventory

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

189

Half-embryo test for identification of irradiated citrus fruit: collaborative study  

NASA Astrophysics Data System (ADS)

A collaborative study on the use of the half-embryo test for the detection of irradiated citrus fruit was undertaken. Collaborative samples of seeds removed from citrus fruit, which were irradiated with doses of 0, 0.2 and 0.5 kGy, were examined by 12 participating laboratories. The percentage of correct identifications, whether irradiated or unirradiated, was 92% of 48 samples after 4 days incubation and 98% after 7 days incubation. Only one sample, irradiated with 0.2 kGy, was incorrectly identified. This collaborative study shows that irradiated citrus fruit can be identified using the half-embryo test and that the test can be applied in practice.

Kawamura, Yoko; Sugita, Takiko; Yamada, Takashi; Saito, Yukio

1996-11-01

190

Early life-stage toxicity test methods for gulf toadfish (Opsanus beta) and results using chlorpyrifos  

SciTech Connect

Gulf toadfish (Opsanus beta) were continuously exposed as embryos, sac fry, and juveniles to technical chlorpyrifos in two 49-day early life-stage toxicity tests. Survival was significantly (alpha = 0.05) reduced only in 150 micrograms/liter. However, toadfish exposed to chlorpyrifos concentrations from 3.7 to 150 micrograms/liter weighted significantly less than control fish: 9% lower in 3.7 micrograms/liter to 62% lower in 150 micrograms/liter. The 96-hr LC50 for juvenile fish was 520 micrograms/liter. Concentrations of chlorpyrifos in toadfish and bioconcentration factors increased with increasing exposure concentration, a condition not generally observed with other marine fishes and other test chemicals. These results demonstrated the procedures for, and the practicality of, early life-stage tests with this marine species. We recommend the use of the gulf toadfish for comparative toxicity testing and for evaluating the toxicity of substances in conjunction with ontogenetical, physiological, and histological investigations of this considerably studied genus. We do not recommend it for routine effects testing.

Hansen, D.J.; Goodman, L.R.; Cripe, G.M.; Macauley, S.F.

1986-02-01

191

HMX: Acute Toxicity Tests in Laboratory Animals.  

National Technical Information Service (NTIS)

The US Army requires information on the acute toxicity potential of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) by oral, dermal and intravenous routes. In addition data on the acute skin and eye irritancy and skin sensitisation potentials of HM...

J. A. Cuthbert K. J. D'Arcy-Burt S. M. Carr

1985-01-01

192

SURVIVAL OF BROOK TROUT EMBRYOS IN THREE EPISODICALLY ACIDIFIED STREAMS  

EPA Science Inventory

The authors evaluated brook trout Salvelinus fontinalis in three streams that undergo episodic acidification during critical periods of embryo development for survival of embryos from egg deposition to preemergence in natural redds and survival of sac fry in toxicity tests done i...

193

Toxicity assessment of sequential leachates of tire powder using a battery of toxicity tests and toxicity identification evaluations.  

PubMed

Approximately 460,000 ton of rubber are dispersed annually along the European roads due to tire wear. Tire rubber is known to leach compounds that are toxic to aquatic organisms. However, the potential effects of tire wear material on aquatic organisms at environmental relevant concentrations, and over time have so far not been extensively studied. In this study, rubber from three different tires was abraded and the powder leached in deionised water. The rubber powder was leached six times sequentially. All leachates were tested for toxicity using standardized toxicity tests including green algae (Pseudokirchneriella subcapitata, 72h growth inhibition), crustaceans (Daphnia magna, 24 and 48h immobility and Ceriodaphnia dubia, 48h survival and 9d reproduction and survival), and zebra fish eggs (Danio rerio, 48h lethality). The reproduction of C. dubia was the most sensitive endpoint tested, with an EC50 of 0.013 g L(-1) up to the third leaching of the most toxic tire, which is similar to a predicted concentration in road runoffs. The toxicity of all tires was reduced by the sequential leachings and after the sixth leaching the EC50s were >0.1 g L(-1) for all endpoints. Toxicity identification evaluations indicated that the toxicity was caused by zinc and organic compounds. PMID:19758678

Wik, Anna; Nilsson, Eva; Källqvist, Torsten; Tobiesen, August; Dave, Göran

2009-11-01

194

Toxic effects of several phthalate esters on the embryos and larvae of abalone Haliotis diversicolor supertexta  

Microsoft Academic Search

As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs).\\u000a In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl)\\u000a phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation

Zhihui Yang; Xiangjing Zhang; Zhonghua Cai

2009-01-01

195

Toxicity of the herbicides Flubalex, Fusilade S and Maloran 50 WP to chicken embryos after administration as single compounds or in combination.  

PubMed

The teratogenic effects of three herbicides (Flubalex, Fusilade S and Maloran 50 WP) were studied in chicken embryos. Each of the three test substances was administered on days 0 and 12 of incubation. Treatment was followed by evaluation on day 19. The compounds were injected into the air-chamber of eggs at three different concentrations. The medium concentration corresponded to that usually applied in chemical plant protection. In order to determine the combined toxicity of the three herbicides, the medium concentration of Maloran 50 WP and three different concentrations of Flubalex of Fusilade S each were administered simultaneously at a final volume of 0.1 ml per egg, at similar times. Evaluation was done on day 19. In tests of individual toxicity, after injection on day 0 of incubation Maloran 50 WP and Flubalex caused a significant reduction in body mass, while Maloran 50 WP and Fusilade S resulted in marked embryonic mortality. After injection on day 12, the medium and the highest concentration of Flubalex and the highest concentration of Fusilade S caused a marked increase in embryonic mortality. The developmental anomalies were of sporadic nature: their incidence increased only after Flubalex treatment, irrespective of the time of administration. The combined administration of Maloran 50 WP and Flubalex on day 0 resulted in a significant or marked body mass reduction in all groups. Embryonic mortality increased substantially after treatment with the highest dose of Flubalex, while all three concentrations of the other two herbicides led to similar results. When treatment was performed on day 12, the two highest concentrations of Flubalex and the highest concentration of Fusilade S caused expressed embryonic mortality. The developmental anomalies did not show a dose-dependent effect in any of the test series. PMID:9055461

Várnagy, L; Varga, T; Hlubik, I; Budai, P; Molnár, E

1996-01-01

196

Rapid toxicity testing based on yeast respiratory activity  

SciTech Connect

Rapid and economical techniques are needed to determine the effects of environmental contaminants. At present, the main methods to assess the impact of pollutants are based on chemical analysis of the samples. Invertebrate and vertebrate exposures have been used over the last two decades in assessing acute and chronic toxicities. However, these tests are labor intensive and require several days to complete. An alternative to whole organism exposure is to determine toxic effects in monocellular systems. Another approach for assessing toxicity is to monitor sensitive, nonspecific, subcellular target sites such as mitochondria. Changes in mitochondrial function which could indicate a toxic effect can be demonstrated readily after addition of a foreign substance. In initial assessments of various chemicals, rat liver mitochondria (RLM) were evaluated as a biological sensor of toxicity. False toxicity assessments will result if these ions are present even though they are generally considered nontoxic. Because of these disadvantages, an alternative mitochondrial system, such as found in bakers yeast, was evaluated.

Haubenstricker, M.E. (Environmental Protection Agency, Ann Arbor, MI (USA)); Meier, P.G.; Mancy, K.H. (Univ. of Michigan, Ann Arbor (USA)); Brabec, M.J. (Eastern Michigan Univ., Ypsilanti (USA))

1990-05-01

197

The Bioaccumulation and Toxicity of Platinum Group Metals in Developing Chick Embryos  

NASA Astrophysics Data System (ADS)

Recent studies showed that platinum group metals (PGMs) such as Pt, Pd, and Rh from automobile catalytic converters, can accumulate in the soft tissues of a variety of living organisms. However, the effects of PGMs on bone and organs development of animals are not clearly understood. To examine these aspects, developing chick embryos were injected with 0.1, 1.0, 5, or 10 ppm solutions of Pt, Rh, Pd, or with a PGMs mixture. 1) Pathological Changes: were observed for all PGM treatments above 1 ppm. Bone Cells Assesment: Chondrocyte cells in thibiotarsus showed decreased diameter and length. 2) PGMs Accumulation in Tissues: was quantified by GFAAS spectrometry on finely ground tissue powder. 3) Bone Demineralization: was detected by micro-Raman spectroscopy imaging on paraffin embedded bone sections. 4) DNA Damage in Cells: was determined by using a Comet assay and fluorescence spectroscopy. Oxidative Damage in Tissues: was analyzed using a glutathione peroxidase assay. The overall results indicated that PGMs presence in our environment raises concerns about their long-term health effects on all organisms.

Pavel, Ioana; Monahan, Jennifer; Markopoulos, Marjorie; Gagnon, Zofia; Nejame, Britney; Cawley, Jacob; Reens, David

2008-10-01

198

Extrapolation of toxic indices among test objects  

PubMed Central

Oligochaeta Tubifex tubifex, fish fathead minnow (Pimephales promelas), hepatocytes isolated from rat liver and ciliated protozoan are absolutely different organisms and yet their acute toxicity indices correlate. Correlation equations for special effects were developed for a large heterogeneous series of compounds (QSAR, quantitative structure-activity relationships). Knowing those correlation equations and their statistic evaluation, one can extrapolate the toxic indices. The reason is that a common physicochemical property governs the biological effect, namely the partition coefficient between two unmissible phases, simulated generally by n-octanol and water. This may mean that the transport of chemicals towards a target is responsible for the magnitude of the effect, rather than reactivity, as one would assume suppose.

Tichy, Milon; Rucki, Marian; Roth, Zdenek; Hanzlikova, Iveta; Vlkova, Alena; Tumova, Jana; Uzlova, Rut

2010-01-01

199

SHORT-TERM CHRONIC TOXICITY TEST USING 'DAPHNIA MAGNA'  

EPA Science Inventory

A seven-day short-term chronic toxicity test using 10-day old Daphnia magna is described as a possible alternative to the Ceriodaphnia life-cycle test. Five tests using sodium pentachlorophenate, conducted during the development of the method, gave test results similar to those p...

200

Evaluation of the PCB-TOX-SPOT Water Toxicity Test.  

National Technical Information Service (NTIS)

The United States Army Center for Environmental Health Research (USACEHR) is developing an Environmental Sentinel Biomonitor (ESB) system to test Army drinking water supplies for the presence of toxic industrial chemicals (TICs). One of the technologies c...

D. E. Trader W. Schalie

2011-01-01

201

MANUAL FOR THE EVALUATION OF LABORATORIES PERFORMING AQUATIC TOXICITY TESTS  

EPA Science Inventory

This manual describes guidelines and standardized procedures for conducting on-site audits and evaluations of laboratories performing toxicity tests. ncluded are pre-survey information activities, on-site evaluation activities, evaluation criteria, organizational history and labo...

202

The Toxicity Estimation Software Tool (T.E.S.T.)  

EPA Science Inventory

The Toxicity Estimation Software Tool (T.E.S.T.) has been developed to estimate toxicological values for aquatic and mammalian species considering acute and chronic endpoints for screening purposes within TSCA and REACH programs....

203

Hypersalinity toxicity thresholds for nine California ocean plan toxicity test protocols.  

PubMed

Currently, several desalination facilities have been proposed to operate or are actually operating in California. These facilities' use of reverse osmosis (RO) may discharge hypersaline reject brine into the marine environment. The risks, if any, this brine would pose to coastal receiving waters are unknown. To test the toxicity of hypersaline brine in the absence of any additional toxic constituents, we prepared brine and tested it with the seven toxicity test organisms listed in the 2009 California Ocean Plan. The most sensitive protocols were the marine larval development tests, whereas the most tolerant to increased salinities were the euryhaline topsmelt, mysid shrimp, and giant kelp tests. Reject brines from the Monterey Bay Aquarium's RO desalination facility were also tested with three species. The effects of the aquarium's brine effluent on topsmelt, mussels, and giant kelp were consistent with those observed in the salinity tolerance experiments. This information will be used by regulators to establish receiving water limitations for hypersaline discharges. PMID:23821235

Voorhees, Jennifer P; Phillips, Bryn M; Anderson, Brian S; Siegler, Katie; Katz, Scott; Jennings, Lydia; Tjeerdema, Ron S; Jensen, Joanna; de la Paz Carpio-Obeso, Maria

2013-11-01

204

Rice seed toxicity tests for organic and inorganic substances  

USGS Publications Warehouse

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

Wang, W.

1994-01-01

205

Rice seed toxicity tests for organic and inorganic substances.  

PubMed

Plant seed toxicity tests can be used to evaluate hazardous waste sites and to assess toxicity of complex effluents and industrial chemicals. Conventional plant seed toxicity tests are performed using culture dishes containing filter paper. Some reports indicate that filter papers might interfere with the toxicity of inorganic substances. In this study, a plastic seed tray was used. Rice was used as the test species.A comparison of results in the literature and this study revealed that variation of test species, methods, exposure duration, and other factors may affect the test results. The results of this study showed that the order of decreasing toxicity of metal ions was Cu>Ag>Ni>Cd>Cr(VI)>Pb>Zn>Mn>NaF for rice. The test results were similar to those reported in the literature for lettuce Ag>Ni>Cd,Cu>Cr(VI)>Zn>Mn, millet Cu,Ni>Cd>Cr(VI)>Zn>Mn, and ryegrass Cu>Ni>Mn>Pb>Cd>Zn>Al>Hg>Cr>Fe. The order of decreasing toxicity of organic herbicides was paraquat, 2,4-D>glyphosate>bromacil. PMID:24221291

Wang, W

1994-01-01

206

40 CFR 797.1300 - Daphnid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...guideline prescribes an acute toxicity test in which daphnids (Daphnia magna or D. pulex ) are exposed to a chemical in static...Test species â(i) Selection. (A) The cladocerans, Daphnia magna or D. pulex, are the test species to be used...

2010-07-01

207

Induction of cytochrome P450 3A1 expression by diallyl disulfide: Protective effects against cyclophosphamide-induced embryo-fetal developmental toxicity.  

PubMed

The protective effects of diallyl disulfide (DADS) on cyclophosphamide (CP)-induced developmental toxicity and the possible mechanisms involved in this protection were investigated in rats. In order to study the mechanisms involved in the protection, we examined the effects of DADS on the expression of cytochrome P450 (CYP) 3A1 in the maternal liver and placenta and oxidative stress in the maternal hepatic tissues caused by CP. CP caused severe embryo-fetal developmental toxicity and hepatic oxidative stress. In contrast, DADS treatment significantly attenuated CP-induced developmental toxicity and oxidative damage in the maternal liver. DADS also significantly increased expression of CYP3A1 in the maternal liver and placenta. These results indicate that the protective effects of DADS against CP-induced developmental toxicity may be due to its ability to promote detoxification of CP, primarily by inducing CYP3A1 expression in the maternal liver and placenta, and its potent antioxidant effects. PMID:24769015

Kim, Sung-Hwan; Lee, In-Chul; Baek, Hyung-Seon; Moon, Changjong; Kim, Sung-Ho; Yoo, Jin Cheol; Shin, In-Sik; Kim, Jong-Choon

2014-07-01

208

Evaluation of alternative reference toxicants for use in the earthworm toxicity test  

SciTech Connect

The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH{sub 4}Cl) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH{sub 4}Cl and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were use to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KCl, followed by NH{sub 4}Cl and 2-chloroacetamide. Toxicants ranked KCl < NH{sub 4}Cl {much_lt} 2-chloroacetamide in terms of health hazard; and KCl = NH{sub 4}Cl > 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH{sub 4}Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.

Yeardley, R.B. Jr. [DynCorp-TAI, Cincinnati, OH (United States); Lazorchak, J.M. [Environmental Protection Agency, Cincinnati, OH (United States); Pence, M.A. [Technology Applications, Inc., Cincinnati, OH (United States)

1995-07-01

209

Real-time in vivo imaging of size-dependent transport and toxicity of gold nanoparticles in zebrafish embryos using single nanoparticle plasmonic spectroscopy.  

PubMed

Noble metal nanoparticles (NPs) show distinctive plasmonic optical properties and superior photostability, enabling them to serve as photostable multi-coloured optical molecular probes and sensors for real-time in vivo imaging. To effectively study biological functions in vivo, it is essential that the NP probes are biocompatible and can be delivered into living organisms non-invasively. In this study, we have synthesized, purified and characterized stable (non-aggregated) gold (Au) NPs (86.2 ± 10.8 nm). We have developed dark-field single NP plasmonic microscopy and spectroscopy to study their transport into early developing zebrafish embryos (cleavage stage) and their effects on embryonic development in real-time at single NP resolution. We found that single Au NPs (75-97 nm) passively diffused into the embryos via their chorionic pore canals, and stayed inside the embryos throughout their entire development (120 h). The majority of embryos (96 ± 3%) that were chronically incubated with the Au NPs (0-20 pM) for 120 h developed to normal zebrafish, while an insignificant percentage of embryos developed to deformed zebrafish (1 ± 1)% or dead (3 ± 3)%. Interestingly, we did not observe dose-dependent effects of the Au NPs (0-20 pM) on embryonic development. By comparing with our previous studies of smaller Au NPs (11.6 ± 0.9 nm) and similar-sized Ag NPs (95.4 ± 16.0 nm), we found that the larger Au NPs are more biocompatible than the smaller Au NPs, while the similar-sized Ag NPs are much more toxic than Au NPs. This study offers in vivo assays and single NP microscopy and spectroscopy to characterize the biocompatibility and toxicity of single NPs, and new insights into the rational design of more biocompatible plasmonic NP imaging probes. PMID:24427540

Browning, Lauren M; Huang, Tao; Xu, Xiao-Hong Nancy

2013-06-01

210

Real-time in vivo imaging of size-dependent transport and toxicity of gold nanoparticles in zebrafish embryos using single nanoparticle plasmonic spectroscopy  

PubMed Central

Noble metal nanoparticles (NPs) show distinctive plasmonic optical properties and superior photostability, enabling them to serve as photostable multi-coloured optical molecular probes and sensors for real-time in vivo imaging. To effectively study biological functions in vivo, it is essential that the NP probes are biocompatible and can be delivered into living organisms non-invasively. In this study, we have synthesized, purified and characterized stable (non-aggregated) gold (Au) NPs (86.2 ± 10.8 nm). We have developed dark-field single NP plasmonic microscopy and spectroscopy to study their transport into early developing zebrafish embryos (cleavage stage) and their effects on embryonic development in real-time at single NP resolution. We found that single Au NPs (75–97 nm) passively diffused into the embryos via their chorionic pore canals, and stayed inside the embryos throughout their entire development (120 h). The majority of embryos (96 ± 3%) that were chronically incubated with the Au NPs (0–20 pM) for 120 h developed to normal zebrafish, while an insignificant percentage of embryos developed to deformed zebrafish (1 ± 1)% or dead (3 ± 3)%. Interestingly, we did not observe dose-dependent effects of the Au NPs (0–20 pM) on embryonic development. By comparing with our previous studies of smaller Au NPs (11.6 ± 0.9 nm) and similar-sized Ag NPs (95.4 ± 16.0 nm), we found that the larger Au NPs are more biocompatible than the smaller Au NPs, while the similar-sized Ag NPs are much more toxic than Au NPs. This study offers in vivo assays and single NP microscopy and spectroscopy to characterize the biocompatibility and toxicity of single NPs, and new insights into the rational design of more biocompatible plasmonic NP imaging probes.

Browning, Lauren M.; Huang, Tao; Xu, Xiao-Hong Nancy

2013-01-01

211

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

PubMed

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 LC50s for 14 and 28 days were 5311 and 5395 microgPb g(-1)soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 microgPb 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 microg g(-1) soil accumulated lead at a faster rate (3.16 microg Pb g(-1)tissue day(-1)) than those in the 3000 microg g(-1) soil (2.21 microg Pb g(-1)tissue day(-1)). The third experiment was a timed experiment with worms cultivated in soil containing 7000 microgPb g(-1)soil. Soil and lead nitrate solution were mixed and stored at 20 degrees 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 time of artificially amended Pb-bearing soils increases the bioavailability of Pb decreases. Thus addition of worms shortly after addition of Pb to soils may result in the over-estimate of Pb toxicity to worms. The current OECD acute worm toxicity test fails to take these two phenomena into account thereby reducing the environmental relevance of the contaminant toxicities it is used to calculate. PMID:12475061

Davies, Nicola A; Hodson, Mark E; Black, Stuart

2003-01-01

212

Economical test methods for developmental neurobehavioral toxicity.  

PubMed Central

The assessment of behavioral changes produced by prenatal or early postnatal exposure to potentially noxious agents requires both the designing of ad hoc tests and the adaptation of tests for adult animals to the characteristics of successive developmental stages. The experience in designing tests is still more limited than in the adaptation of tests, but several tests have already proven their usefulness; some examples are the suckling test, the homing test, and evaluations of dam-pup and pup-pup interactions. Functional observational batteries can exploit the development at specified postnatal ages of several reflexes and responses that are absent at birth in altricial rodent species with a short pregnancy such as the rat and the mouse. In neonates, the assessment of early treatment effects can rely not only on deviations from normal responding but also on changes in the time of appearance of otherwise normal response patterns. The same applies to other end points such as responses to pain and various types of spontaneous motor/exploratory activities, including reactivity to a variety of drug challenges that can provide information on the regulatory systems whose development may be affected by early treatments. In particular, the analysis of ontogenetic dissociations (i.e., differential early treatment effects depending jointly on developmental stage at the time of exposure, age of testing, and response end point) can be of considerable value in the study of treatments' mechanisms of action. Overall, it appears that behavioral teratological assessments can be effectively used both proactively, i.e., in risk assessment prior to any human exposure, and reactively. In the latter case, these assessments could have special value in the face of agents suspected to produce borderline changes in developing humans, whose innocuousness or noxiousness can be difficult to establish in the absence of hard evidence of teratogenicity.

Bignami, G

1996-01-01

213

Acute systemic toxicity—prospects for tiered testing strategies  

Microsoft Academic Search

After many years of controversy and debate, the LD50 test was finally deleted by the end of 2002. Three alternative animal tests, the Fixed Dose Procedure, the Acute Toxic Class Method and the Up and Down Procedure have been developed which give rise to significant improvements in animal welfare. They have recently undergone revision to improve their scientific performance but

P. A. Botham

2004-01-01

214

THE ROLE OF INORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING  

EPA Science Inventory

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...

215

GENETIC VARIATION FOR COPPER RESISTANCE IN FATHEAD MINNOW TOXICITY TESTS  

EPA Science Inventory

Unexplained variation in the results of aquatic organism toxicity tests is a consistently observed and troubling phenomenon. Possible sources of variation include differences in condition or nutritional status of the population prior to the test, as well as age, density and hand...

216

Some possible reference materials for fire toxicity tests  

NASA Technical Reports Server (NTRS)

Suitable reference materials need to be selected in order to standardize any test method. The evaluation of cotton, polyethylene, polyether sulfone, polycarbonate, polystyrene, and polyurethane flexible and rigid foams as possible reference materials for the University of San Francisco/NASA toxicity screening test method is discussed.

Hilado, C. J.; Solis, A. N.

1977-01-01

217

PROPOSED TEST PROTOCOL TO DETERMINE TOXICANT LEACHING INTO POTABLE WATER  

EPA Science Inventory

Research was conducted to develop a general test protocol to identify the possible deterioration of water quality as a result of leaching of toxicants from distribution/transmission pipes and tanks during distribution and storage of potable water. The developed protocol was teste...

218

APPROPRIATE DURATIONS AND MEASURES FOR 'CERIODAPHNIA' TOXICITY TESTS  

EPA Science Inventory

The Mount-Norberg test, which employs a measure of the size of three broods over seven days, has been used extensively in toxicity testing. The authors have applied it to estimating sublethal ecosystem effects of complex effluents in the Raisin River drainage (of Michigan) on the...

219

POREWATER CHEMISTRY: EFFECTS OF SAMPLING, STORAGE, HANDLING, AND TOXICITY TESTING  

EPA Science Inventory

As a general principle, it is nearly impossible to remove a porewater sample from sediment, use it in a toxicity testing vessel with test organisms, and prevent changes in the chemistry of the natural and anthropogenic organic and inorganic constituents. The degree of change in t...

220

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

PubMed

While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining their ability to inhibit differentiation of embryonic stem cells into spontaneously contracting cardiomyocytes. Four well characterized silica nanoparticles of various sizes were used to investigate whether nanomaterials are capable of inhibition of differentiation in the embryonic stem cell test. Nanoparticle size distributions and dispersion characteristics were determined before and during incubation in the stem cell culture medium by means of transmission electron microscopy (TEM) and dynamic light scattering. Mouse embryonic stem cells were exposed to silica nanoparticles at concentrations ranging from 1 to 100 microg/ml. The embryonic stem cell test detected a concentration dependent inhibition of differentiation of stem cells into contracting cardiomyocytes by two silica nanoparticles of primary size 10 (TEM 11) and 30 (TEM 34) nm while two other particles of primary size 80 (TEM 34) and 400 (TEM 248) nm had no effect up to the highest concentration tested. Inhibition of differentiation of stem cells occurred below cytotoxic concentrations, indicating a specific effect of the particles on the differentiation of the embryonic stem cells. The impaired differentiation of stem cells by such widely used particles warrants further investigation into the potential of these nanoparticles to migrate into the uterus, placenta and embryo and their possible effects on embryogenesis. PMID:19631676

Park, Margriet V D Z; Annema, Wijtske; Salvati, Anna; Lesniak, Anna; Elsaesser, Andreas; Barnes, Clifford; McKerr, George; Howard, C Vyvyan; Lynch, Iseult; Dawson, Kenneth A; Piersma, Aldert H; de Jong, Wim H

2009-10-01

221

DEVELOPMENTAL TOXICITY OF METHANOL: PATHOGENESIS IN CD-1 AND C57BL/6J MICE EXPOSED IN WHOLE EMBRYO CULTURE  

EPA Science Inventory

BACKGROUND: Methanol causes axial skeleton and craniofacial defects in both CD-1 and C57BL/6J mice during gastrulation, but C57BL/6J embryos are more severely affected. We evaluated methanol-induced pathogenesis in CD-1 and C57BL/6J embryos exposed during gastrulation in whole em...

222

A COUPLED MICROSOMAL-ACTIVATING/EMBRYO CULTURE SYSTEM: TOXICITY OF REDUCED BETA-NICOTINAMIDE ADENINE DINUCLEOTIDE PHOSPHATE (NADPH)  

EPA Science Inventory

An NADPH-dependent microsomal-activating system has been coupled to a rat embryo culture in vitro. No embryonic morphological abnormalities or decrease in final yolk sac or embryo DNA and protein contents occurred when 0.2 mM NADPH was used in this coupled system. In contrast, 1....

223

A Coupled Microsomal-Activating/Embryo Culture System: Toxicity of Reduced beta-Nicotinamide Adenine Dinucleotide Phosphate (NADPH).  

National Technical Information Service (NTIS)

An NADPH-dependent microsomal-activating system has been coupled to a rat embryo culture in vitro. No embryonic morphological abnormalities or decrease in final yolk sac or embryo DNA and protein contents occurred when 0.2 mM NADPH was used in this couple...

K. T. Kitchin M. K. Sanyal B. P. Schmid

1980-01-01

224

Using toxicity testing to evaluate electrochemical reactor operations.  

PubMed

In the present study, the Microtox® test was used to track the toxicity of electrochemical effluents to the marine bacteria Vibrio fischeri as a function of reaction time. When electrochemistry was used to degrade aqueous phenol using different reactor configurations, two reaction pathways were identified, chlorine substitution and oxidation, depending on whether the electrolyte contained chloride. For a boron-doped diamond (BDD) anode, electrochemistry using Na?SO? electrolyte produced a significantly more toxic effluent than when using NaCl electrolyte with all other conditions remaining the same. This effect is attributed to the reaction pathway, specifically the production of benzoquinone. Benzoquinone was produced only during electrochemistry using Na?SO? and is the most toxic potential intermediate, having nearly 800 times more toxicity than phenol. Although the use of NaCl produced a lower toxicity effluent than Na?SO?, caution should be observed because of the production of chlorinated phenols, which can be of special environmental concern. When comparing graphite rod and BDD plate anodes in terms of toxicity evolution when using Na?SO?, BDD was found to produce a lower toxicity effluent; this is a result of the increased oxidizing power of BDD, reducing the formation of benzoquinone. In this comparison, the type of anode material/electrode configuration did not seem to affect which intermediates were detected but did affect the quantity of and rate of production of intermediates. PMID:22170029

Saylor, Greg L; Chen, Linxi; Kupferle, Margaret J

2012-03-01

225

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

Microsoft Academic Search

The issue of endocrine disruption has, in view of human risk assessment,\\u000araised the question on whether more sensitive test methods are needed to\\u000adetect the reproductive toxic properties of xenobiotic compounds with\\u000aendocrine properties. We studied six known and alleged endocrine\\u000adisruptors in an existing reproductive toxicology screening test to see\\u000aif this test would score these compounds as

Piersma AH; Verhoef A; Elvers LH; Wester PW

2007-01-01

226

Baker's yeast assay procedure for testing heavy metal toxicity  

SciTech Connect

Baker's yeast (Saccharomyces cerevisiae) is microorganism which is commercially available and sold as packaged dry pellets in any food store at low cost. Studies have been undertaken on the effects of organic xenobiotics as well as heavy metals on yeast metabolism. This type of study has been generally useful in examining the mechanism(s) of chemical toxicity. However, a rapid and quantitative toxicity test using S. cerevisiae as the test organism has not been developed. The purpose of this study was to develop a toxicity assay for heavy metals, using commercial dry yeast as the test microorganism. This rapid and simple procedure is based on the reduction of 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyltetrazolium chloride (INT) to INT-formazan by the yeast electron transport system. The scoring of active cells following exposure to heavy metals was undertaken according to the MINT (malachite green-INT) method developed by Bitton and Koopman.

Bitton, G.; Koopman, B.; Wang, H.D.

1984-01-01

227

Preliminary investigation of lethally toxic sera of sudden infant death syndrome victims and neutralisation by commercially available immunoglobulins and adult sera  

Microsoft Academic Search

The aim of the study was to test the hypotheses (i) that sudden infant death syndrome sera are toxic to 11-day old chick embryos and (ii) that such a toxicity can be counteracted by immunoglobulin or adult sera. Serum samples from 11 SIDS victims and five controls were tested for lethal toxicity in the chick embryo bioassay. Five serum samples

Nicola M. Sayers; David B. Drucker; Ian V. Hutchinson; Anthony J. Barson

1999-01-01

228

Toxicity Testing in the 21st Century: Using the New Toxicity Testing Paradigm to Create a Taxonomy of Adverse Effects  

PubMed Central

Distinguishing adaptive from adverse responses is fundamental to understanding toxicity and to implementing regulatory guidelines that are protective of human health. However, what we consider to be an adverse effect may change over time as the cultural acceptance of risk alters and new knowledge and insight accumulate. The fact that the identification of an adverse effect is subject to change is obvious, necessary, and uncomfortable. In this commentary, a framework for defining adverse effects is proposed for the emerging paradigm of toxicity testing in the 21st century—a paradigm that focuses on human cells, in vitro approaches, toxicity pathways, and high-throughput techniques. The traditional meaning of an adverse effect as a change at the organismal level is not compatible with this new system of toxicity testing. Instead, based on the experience of accident investigators, we propose that a Toxicological Factors Analysis and Classification System will use the database resulting from the high-throughput toxicity testing of the future to develop a Taxonomy of Adverse Effects. Similar to an accident, predisposing “latent failures” identified within categories of the toxicant response database will be associated with the “active failure” of an adverse effect.

Boekelheide, Kim; Campion, Sarah N.

2010-01-01

229

Eugenic selection benefits embryos.  

PubMed

The primary question to be addressed here is whether pre-implantation genetic diagnosis (PGD), used for both negative and positive trait selection, benefits potential supernumerary embryos. The phrase 'potential supernumerary embryos' is used to indicate that PGD is typically performed on a set of embryos, only some of which will be implanted. Prior to any testing, each embryo in the set is potentially supernumerary in the sense that it may not be selected for implantation. Those embryos that are not selected, and hence destroyed or frozen, are 'actually supernumerary'. The argument to be advanced is hypothetical: If embryos may be said to benefit or be harmed by our actions, then PGD used to select for an embryo or embryos with the highest expected Wellbeing benefits potential supernumerary embryos. The argument shows that the 'non-identity' problem is not sufficient to show that eugenic selection does not benefit supernumerary embryos. PMID:22845885

Walker, Mark

2014-06-01

230

Vitrification of preimplantation stages of mouse embryos.  

PubMed

Three vitrification solutions (VS) namely VS1 (5.5 mol ethylene glycol l-1 and 2.5 mol glycerol l-1), VS11 (6.0 mol ethylene glycol l-1 and 1.8 mol glycerol l-1) and VS14 (5.5 mol ethylene glycol l-1 and 1 mol sucrose l-1) were tested for cryopreservation by vitrification of all developmental stages of mouse preimplantation embryos. In these experiments all preparative work was at room temperature (25 degrees C). VS1 was toxic to embryos at and earlier than the eight-cell stage, whereas VS11 was toxic to the four-cell and earlier stages. VS14 was the least toxic VS. All three VS resulted in good viability of vitrified Swiss Outbred day-4 embryos (morulae, early blastocysts and blastocysts) in vitro and vitrification with VS14 resulted in no loss of viability in all preimplantation stage Swiss Outbred embryos except one-cell embryos. One-cell F1 embryos were vitrified successfully with VS14 and VS1. The minimal equilibration time essential for successful vitrification of embryos suggests that concentration of the intracellular solutes by dehydration has a major role in establishing conditions conducive to intracellular vitrification. Studies in vitro suggested that sucrose dilution was not necessary in the removal of cryoprotectant from vitrified eight-cell and day-4 mouse embryos but, in contrast, development of vitrified day-4 embryos in vivo was better when the VS was diluted with sucrose.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8410811

Ali, J; Shelton, J N

1993-07-01

231

Studying the effects of genistein on gene expression of fish embryos as an alternative testing approach for endocrine disruption.  

PubMed

Assessment of endocrine disruption currently relies on testing strategies involving adult vertebrates. In order to minimize the use of animal tests according to the 3Rs principle of replacement, reduction and refinement, we propose a transcriptomics and fish embryo based approach as an alternative to identify and analyze an estrogenic activity of environmental chemicals. For this purpose, the suitability of 48 h and 7 days post-fertilization zebrafish and medaka embryos to test for estrogenic disruption was evaluated. The embryos were exposed to the phytoestrogen genistein and subsequently analyzed by microarrays and quantitative real-time PCR. The functional analysis showed that the genes affected related to multiple metabolic and signaling pathways in the early fish embryo, which reflect the known components of genistein's mode of actions, like apoptosis, estrogenic response, hox gene expression and steroid hormone synthesis. Moreover, the transcriptomic data also suggested a thyroidal mode of action and disruption of the nervous system development. The parallel testing of two fish species provided complementary data on the effects of genistein at gene expression level and facilitated the separation of common from species-dependent effects. Overall, the study demonstrated that combining fish embryo testing with transcriptomics can deliver abundant information about the mechanistic effects of endocrine disrupting chemicals, rendering this strategy a promising alternative approach to test for endocrine disruption in a whole organism in-vitro scale system. PMID:23017276

Schiller, Viktoria; Wichmann, Arne; Kriehuber, Ralf; Muth-Köhne, Elke; Giesy, John P; Hecker, Markus; Fenske, Martina

2013-01-01

232

Resolving some practical questions about Daphnia acute toxicity tests  

SciTech Connect

Acute toxicity tests were performed with six age groups of Daphnia magna, ranging from less than or equal to6 h to 216 h, and with five chemicals, selected on the basis of their physical and chemical properties as well as their acute toxicity to D. magna. The age of the daphnids did not significantly alter the 48-h EC/sub 50/ values for the chemicals tested. The maximum difference observed in the 48-h EC/sub 50/ values between the 6-h and 216-h age groups was a factor of 3.9 for linear alkylbenzene sulfonate (LAS). For purposes of standardization, it appears that D. magna up to 48 h of age at the beginning of the test can be used to conduct acute toxicity tests with most chemicals. The results of static acute toxicity tests conducted with butylbenzyl phthalate (BBP) and D. magna in the presence and absence of several commonly used solvents indicate that the acute toxicity of this chemical is not altered by the use of a solvent carrier. The 48-h EC/sub 50/ value for BBP without a solvent was 1.0 mg/L, compared with a range of 1.6 to 2.2 mg/L when acetone, dimethylformamide, ethanol, or triethylene glycol were used as solvent carriers. The acute toxicities of the solvents in the absence of BBP were also determined for D. magna. The values ranged from 9.3 to 52.4 g/L. The results of static acute tests performed with D. magna and BBP in the presence of various concentrations of daphnid foods (algae or trout chow), indicate that the 48-h EC/sub 50/ values increase proportionally with an increase in food concentrations. These results suggest that acute toxicity tests with D. magna should be conducted in the presence of food with chemicals with a high Ksigma if the results are to be used to select the test concentrations for a chronic study with daphnids. The type of food and the concentration used in the acute test should be the same as those used in a chronic test.

Barera, Y.; Adams, W.J.

1981-10-01

233

Functional toxicology: tools to advance the future of toxicity testing  

PubMed Central

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.

Gaytan, Brandon D.; Vulpe, Chris D.

2014-01-01

234

Differential effect of solar light in increasing the toxicity of silver and titanium dioxide nanoparticles to a fish cell line and zebrafish embryos.  

PubMed

The increasing use of silver (Ag) and titanium dioxide (TiO2) nanoparticles (NPs) in consumer products and their inevitable seepage into the environment prompted us to investigate their potential toxicity to a fish cell line (BF-2) and zebrafish embryos under dark and Simulated Solar Light (SSL) exposure conditions. Using high throughput screening (HTS) platforms, we showed that the oxidative stress-dependent cytotoxicity and embryonic toxicity of NPs were significantly increased upon exposure to SSL. While, the toxicity of TiO2 NPs under SSL exposure could be explained by hydroxyl radical generation, the enhanced toxicity of Ag NPs under SSL exposure was due to surface oxidation and physicochemical modification of Ag NPs and shedding of Ag(+), leading to an increased bioavailability of silver. Our observations that solar light could induce physicochemical transformation of TiO2 and Ag NPs and enhance their toxic potential emphasizes the need for conducting future toxicity studies under environmentally relevant exposure conditions to guide decision making on the safe handling of NPs. PMID:24811346

George, Saji; Gardner, Hannah; Seng, Eng Khuan; Chang, Hengky; Wang, Chunyan; Yu Fang, Crystal Hay; Richards, Mark; Valiyaveettil, Suresh; Chan, Woon Khiong

2014-06-01

235

The Third FRAME Toxicity Committee: working toward greater implementation of alternatives in toxicity testing.  

PubMed

FRAME (the Fund for the Replacement of Animals in Medical Experiments; http://www. frame.org.uk) is a scientific charity, which has, for over 30 years, been advocating and conducting its own research on the application of the Three Rs (reduction, refinement and replacement) to animal experimentation. FRAME develops and validates scientifically based replacement alternative methods to facilitate their acceptance by scientists and regulators. As part of these activities, FRAME established a FRAME Toxicity Committee in 1979, and a report of its work was published in 1982, and discussed in the proceedings of a subsequent meeting, published in 1983. A Second Toxicity Committee formed in 1988, reported its work in 1990, which was discussed in the proceedings of a subsequent conference, published in 1991. The work of these committees was extremely successful and influential in laying the foundation for later activities in alternatives research. A Third FRAME Toxicity Committee was formed in 1999, since much progress had been achieved in the previous decade, especially with regard to the successful validation of several non-animal replacement methods and the start of their regulatory acceptance. Moreover, some new test methods are on the point of being validated, and many new techniques and discoveries are impacting on toxicity testing. Also, interest in reduction and refinement in toxicology has increased. However, there is considerable scope and need for the further implementation of the Three Rs in toxicity testing, especially due to recent plans for the large-scale testing of high-production volume, hormonally-active and existing chemicals, and the increasing use of transgenic animal models. The new committee comprises 18 experts from industry, academia, animal welfare, legislative and regulatory bodies, with one observer from the UK Government Home Office. The main objective is to review progress made in the application of the Three Rs in the development and safety evaluation of medicines, biologicals, cosmetics, agrochemicals and other products, as well as industrial chemicals, and to make recommendations as a basis for further sensible progress according to sound scientific and ethical criteria. The main committee is to be augmented by several working parties that will focus on specific scientific issues: 1) targeted risk assessment versus hazard identification; 2) data sharing; 3) endocrine disruption; and 4) carcinogenicity testing. The Committee is also to publish a status report on the current situation regarding alternatives in toxicity testing, based on the recommendations of the Second Toxicity Committee, and will organise a conference to discuss its overall conclusions and recommendations. PMID:23581152

Combes, Robert D; Balls, Michael; Bansil, Lee; Barratt, Martin; Bell, David; Botham, Philip; Broadhead, Caren; Clothier, Richard; George, Elizabeth; Fentem, Julia; Jackson, Michael; Indans, Ian; Loizou, George; Navaratnam, Vyra; Pentreath, Victor; Phillips, Barry; Stemplewski, Henry; Stewart, Jane

2004-06-01

236

Sun light mediated synthesis of gold nanoparticles as carrier for 6-mercaptopurine: Preparation, characterization and toxicity studies in zebrafish embryo model  

SciTech Connect

Highlights: ? Gold nanoparticles prepared using eco-friendly method with good in vitro stability. ? Can be used as drug delivery system. ? Did not show any toxicity in zebrafish embryo. ? More toxic to cancer cells when compared to N-Au-Mp and Mp. -- Abstract: The objective of this study is to synthesize green chemistry based gold nanoparticles by sun light irradiation method. The prepared gold nanoparticles (AuNPs) were modified using folic acid and then coupled with 6-mercaptopurine. These modified nanoparticles were used as a tool for targeted drug delivery to treat laryngeal cancer. In the present study, novel bionanocomposites containing nutrient agar coated gold nano particles (N-AuNPs) coupled with 6-mercaptopurine (drug) (N-AuNPs-Mp), folic acid (ligand) (N-AuNPs-Mp-Fa) and rhodamine (dye) (N-AuNPs-Rd), a fluorescent agent, were prepared and characterized by IR, UV, TEM, Particle size analysis and in vitro stability. The toxicity and fluorescence of N-Au was studied using zebrafish embryo model. The in vitro cytotoxicity of free Mp, N-Au-Mp and N-Au-Mp-Fa against HEp-2 cells was compared and found that the amount of Mp required to achieve 50% of growth of inhibition (IC{sub 50}) was much lower in N-Au-Mp-Fa than in free Mp and N-Au-Mp.

Ganeshkumar, Moorthy [Department of Biochemistry, Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600020 (India)] [Department of Biochemistry, Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600020 (India); Sastry, Thotapalli Parvathaleswara [Bioproducts Laboratory, Central Leather Research Institute, Chennai 600020 (India)] [Bioproducts Laboratory, Central Leather Research Institute, Chennai 600020 (India); Sathish Kumar, Muniram [Department of Pharmaceutics, Anna University, Trichy, Tamilnadu (India)] [Department of Pharmaceutics, Anna University, Trichy, Tamilnadu (India); Dinesh, Murugan Girija [Thanthai Hansroever College, Perambalur, Tamilnadu (India)] [Thanthai Hansroever College, Perambalur, Tamilnadu (India); Kannappan, Sudalyandi [Central Institute of Brackish Water Aquaculture, Chennai 600028 (India)] [Central Institute of Brackish Water Aquaculture, Chennai 600028 (India); Suguna, Lonchin, E-mail: slonchin@yahoo.co.uk [Department of Biochemistry, Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600020 (India)] [Department of Biochemistry, Central Leather Research Institute, Council of Scientific and Industrial Research, Chennai 600020 (India)

2012-09-15

237

Estimation of the hazard of landfills through toxicity testing of leachates—I. Determination of leachate toxicity with a battery of acute tests  

Microsoft Academic Search

Twenty-seven landfill leachates were tested on a battery of conventional toxicity tests (microalgae, daphnids, duckweeds) and new microbiotests (rotifers, crustaceans, protozoans, luminescent bacteria).The toxicity varied substantially from one test species to the other, from one site to the other, as well as from one type of landfill to the other. Leachates of domestic wastes were significantly more toxic than those

Clément Bernard; Persoone Guido; Janssen Colin; Anne Le Dû-Delepierre

1996-01-01

238

Contact Toxicity of 40 Insecticides Tested on Pandora Moth Larvae.  

National Technical Information Service (NTIS)

Forty insecticides and an antifeeding compound were tested on pandora moth larvae (Coloradia pandora Blake) in the second and third instars. A total of 21 insecticides were more toxic at LD90 than DDT, providing a good choice of candidates for field testi...

R. L. Lyon

1971-01-01

239

COMPUTER INTERFACED TOXICITY TESTING SYSTEM FOR SIMULATING VARIABLE EFFLUENT LOADING  

EPA Science Inventory

Water quality criteria and standards are based primarily on toxicity tests carried out with single chemicals whose concentration is as nearly constant as possible. In the 'real world', however, organisms are exposed to mixtures of chemicals which usually have markedly fluctuating...

240

A FIELD VALIDATION OF TWO SEDIMENT-AMPHIPOD TOXICITY TESTS  

EPA Science Inventory

A field validation study of two sediment-amphipod toxicity tests was conducted using sediment samples collected subtidally in the vicinity of a polycyclic aromatic hydrocarbon (PAH)-contaminated Superfund site in Elliott Bay, WA, USA. Sediment samples were collected at 30 stati...

241

Troubleshooting methods for toxicity testing of airborne chemicals in vitro  

Microsoft Academic Search

Toxicology studies of adverse effects induced by inhaled chemicals are technically challenging, due to the requirement of highly controlled experimental conditions needed to achieve reproducible and comparable results. Therefore, many considerations must be fulfilled before adopting in vitro bioassay test systems for toxicity screening of airborne materials. However, recent methodological and technical breakthroughs of in vitro methods have the potential

Shahnaz Bakand; Amanda Hayes

2010-01-01

242

TOXICITY TEST USING LIFE STAGES OF 'CHAMPIA PARVULA' (RHODOPHYTA)  

EPA Science Inventory

A static-renewal, 11- to 14-day toxicity test has been developed using the life cycle of the marine red alga Champia parvula (C. Ag.) Harv. It measures the vegetative growth, formation of tetrasporangia (meiosis), and formation of cystocarps (sexual fusion). The procedure has bee...

243

Toxicity testing: creating a revolution based on new technologies  

Microsoft Academic Search

Biotechnology is evolving at a tremendous rate. Although drug discovery is now heavily focused on high throughput and miniaturized screening, the appli- cation of these advances to the toxicological assess- ment of chemicals and chemical products has been slow. Nevertheless, the impending surge in demands for the regulatory toxicity testing of chemicals provides the impetus for the incorporation of novel

Nirmala Bhogal; Christina Grindon; Robert Combes; Michael Balls

2005-01-01

244

Toxicity of waste drilling fluids in modified allium test  

Microsoft Academic Search

The toxicity of four waste water samples from reserve pit upon the root-tip cells of Allium ascalonicum L. was researched by applying modified Allium test. The samples were a mixture of substances and their chemical composition was only partly known. The first task was to find out the optimal duration for root-tips treatment. The treatment lasting 48 h has been

Željka Vidakovi?; Dražena Papeš; Mihovil Tomi?

1993-01-01

245

COMPARATIVE TOXICITY OF DIURON ON SURVIVAL AND GROWTH OF PACIFIC TREEFROG, BULLFROG, RED-LEGGED FROG, AND AFRICAN CLAWED FROG EMBRYOS AND TADPOLES  

EPA Science Inventory

The effects of the herbicide diuron on survival and growth of Pacific treefrog (Pseudacris regilla),bullfrog(Rana catesbeiana), red-legged frog(Rana aurora),and African clawed frog(Xenopus laevis)embryos and tadpoles were determined in static-renewal tests. P.regilla and X.laevis...

246

Random walk of single gold nanoparticles in zebrafish embryos leading to stochastic toxic effects on embryonic developments  

Microsoft Academic Search

We have synthesized and characterized stable (non-aggregating, non-photobleaching and non-blinking), nearly monodisperse and highly-pure Au nanoparticles, and used them to probe nanoparticle transport and diffusion in cleavage-stage zebrafish embryos and to study their effects on embryonic development in real-time. We found that single Au nanoparticles (11.6 +\\/- 0.9 nm in diameter) passively diffused into the chorionic space of the embryos

Lauren M. Browning; Kerry J. Lee; Tao Huang; Prakash D. Nallathamby; Jill E. Lowman; Xiao-Hong Nancy Xu

2009-01-01

247

Impact of toxicological properties of sulfonamides on the growth of zebrafish embryos in the water.  

PubMed

Extensive use of pharmaceutical compounds may result in contamination of water bodies lying adjacent to areas where there is a high level of human activity. To evaluate potential risks to fish embryos, three sulfonamides were investigated, by means of an extended zebrafish (Danio rerio) toxicity test. The bio-toxicity of antibacterial sulfonamides, at low concentrations, was investigated by observing lethal and sub-lethal effects on embryos and larvae. Results indicated that sulfonamides caused obvious toxic effects on spontaneous movements, heartbeats and hatching of t embryos, and also resulted in malformations in embryos and larvae. A significant toxicity effect was observed in zebrafish embryos and larvae that had been exposed to a low concentration of sulfadimidine (0.001 mg/L), and a significant difference was noted between the exposed and the blank control groups. Exposure to a low concentration of sulfonamide resulted in characteristic malformations, including pericardial edema, yolk sac edema, hemoglutinations, tail deformation and swim bladder defects. PMID:24141258

Lin, Tao; Chen, Yanqiu; Chen, Wei

2013-11-01

248

In vitro Cell Culture Model for Toxic Inhaled Chemical Testing.  

PubMed

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

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

2014-01-01

249

An evaluation of the whole effluent toxicity test method  

SciTech Connect

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 position that the EPA test is neither reasonable nor accurate and thus cannot adequately establish the impact of NPDES outfall discharges on receiving streams.

Osteen, D.V.

1999-12-17

250

Effect of test conditions on relative toxicity rankings of fifteen materials  

NASA Technical Reports Server (NTRS)

Fifteen materials were evaluated for relative toxicity of pyrolysis effluents, using different test conditions in the USF methodology. Wool fabrics were consistently among the most toxic materials, and polystyrene and polychloroprene flexible foam were consistently among the least toxic materials.

Hilado, C. J.; Cumming, H. J.

1977-01-01

251

Modulation of cupric ion activity by pH and fulvic acid as determinants of toxicity in Xenopus laevis embryos and larvae  

SciTech Connect

An ion-specific electrode measured cupric ion activity modulated by fulvic acid (FA) and pH in a series of modified Frog Embryo Teratogenesis Assay--Xenopus (FETAX) toxicity assays. Hydrogen ion concentration was the primary determinant of cupric ion activity, while FA played a smaller but significant role. Fulvic acid was a weak copper complexing agent at pH 5.50. At pH 5.50 there was slight reduction of ionic activity and a subsequent attenuation of copper toxicity with 5.0 mg/L FA. At pH 7.50, FA also had a mild attenuating effect on copper toxicity. At pH 6.50, copper was strongly complexed by FA at total copper (TCu) concentrations below its pH-dependent solubility limit. At TCu concentrations above the solubility limit FA enhanced toxicity. There was more cupric ion activity measured in the presence of 0.5 and 5.0 mg/L FA than without it at TCu concentrations above the solubility limit. The proposed mechanism for this behavior was FA action as a nucleation inhibitor. Under the chemical conditions of the pH 6.50 experiments, a stable supersaturation of copper was formed, resulting in a more toxic aqueous matrix.

Buchwalter, D.B. [Oregon State Univ., Corvallis, OR (United States). Toxicology Program]|[ManTech Environmental Technology, Inc., Corvallis, OR (United States); Linder, G. [ManTech Environmental Technology, Inc., Corvallis, OR (United States); Curtis, L.R. [East Tennessee State Univ., Johnson City, TN (United States). Dept. of Environmental Health

1996-04-01

252

Use of neomysis mercedis (crustacea: mysidacea) for estuarine toxicity tests  

SciTech Connect

The mysid Neomysis mercedis was examined as a test organism for use in acute toxicity tests at intermediate salinities characteristic of estuarine waters. Several sensitive invertebrate species are available for marine assessments (mysids) and freshwater tests (cladocerans), but few are available for estuarine toxicity tests. Observations in the laboratory indicate that Neomysis mercedis can be reared successfully at a temperature of 17[degrees]C, a salinity of 2%, and a population density less than 5/L. Brine shrimp nauplii Artemia salina, algae, and commercial foods were used to sustain mysid cultures. Neomysis mercedis is vivaparous and can complete its life cycle in 3-4 months. Neomysis mercedis is as sensitive as or more sensitive to toxicants than the marine mysid Mysidopsis bahia and the freshwater cladocerans Daphnia magna, Ceriodaphnia dubia, and Simocephalus serrulatus. The mean 96-h LC50 values (concentrations lethal to half the test animals) for N. mercedis, in increasing order, were 0.20 [mu]g/L for thiobencarb, and for malathion, 14 [mu]g/L for carbofuran, 150 [mu]g/L for copper sulfate, 280 [mu]g/L for thiobencarb, and 1,600 [mu]g/L for molinate. Neonates (5 d postrelease) were generally more sensitive than older juveniles. Coefficients of variation (100[center dot]SD/mean) of LC50 values varied from 21 to 35%. 37 refs., 2 figs., 7 tabs.

Brandt, O.M.; Fujimura, R.W.; Finlayson, B.J. (Aquatic Toxicology Laboratory, Elk Grove, CA (United States))

1993-03-01

253

A Potency Test for Trachoma Vaccine Utilizing the Mouse Toxicity Prevention Test.  

National Technical Information Service (NTIS)

A quantitative modification of the mouse toxicity prevention test is described for potency assay of trachoma vaccine. The method of toxicity titration of toxin was revised. Closely spaced dilutions (3:4) of infected yolk sac suspension (ranging from 5% to...

S. P. Wang J. T. Grayston

1967-01-01

254

Decreased dissolution of ZnO by iron doping yields nanoparticles with reduced toxicity in the rodent lung and zebrafish embryos.  

PubMed

We have recently shown that the dissolution of ZnO nanoparticles and Zn(2+) shedding leads to a series of sublethal and lethal toxicological responses at the cellular level that can be alleviated by iron doping. Iron doping changes the particle matrix and slows the rate of particle dissolution. To determine whether iron doping of ZnO also leads to lesser toxic effects in vivo, toxicity studies were performed in rodent and zebrafish models. First, we synthesized a fresh batch of ZnO nanoparticles doped with 1-10 wt % of Fe. These particles were extensively characterized to confirm their doping status, reduced rate of dissolution in an exposure medium, and reduced toxicity in a cellular screen. Subsequent studies compared the effects of undoped to doped particles in the rat lung, mouse lung, and the zebrafish embryo. The zebrafish studies looked at embryo hatching and mortality rates as well as the generation of morphological defects, while the endpoints in the rodent lung included an assessment of inflammatory cell infiltrates, LDH release, and cytokine levels in the bronchoalveolar lavage fluid. Iron doping, similar to the effect of the metal chelator, DTPA, interfered in the inhibitory effects of Zn(2+) on zebrafish hatching. In the oropharyngeal aspiration model in the mouse, iron doping was associated with decreased polymorphonuclear cell counts and IL-6 mRNA production. Doped particles also elicited decreased heme oxygenase 1 expression in the murine lung. In the intratracheal instillation studies in the rat, Fe doping was associated with decreased polymorphonuclear cell counts, LDH, and albumin levels. All considered, the above data show that Fe doping is a possible safe design strategy for preventing ZnO toxicity in animals and the environment. PMID:21250651

Xia, Tian; Zhao, Yan; Sager, Tina; George, Saji; Pokhrel, Suman; Li, Ning; Schoenfeld, David; Meng, Huan; Lin, Sijie; Wang, Xiang; Wang, Meiying; Ji, Zhaoxia; Zink, Jeffrey I; Mädler, Lutz; Castranova, Vincent; Lin, Shuo; Nel, Andre E

2011-02-22

255

Normal Calves Obtained after Direct Transfer of Vitrified Bovine Embryos Using Ethylene Glycol, Trehalose, and Polyvinylpyrrolidone  

Microsoft Academic Search

In the present study, IVF bovine embryos were vitrified using as the cryoprotectants, ethylene glycol plus trehalose plus the polymer, polyvinylpyrrolidone (PVP). In Experiment I, toxicity of the vitrification solution (VS) containing 20% PVP was tested in relation to temperature and exposure time. One hundred percent embryo development was observed with treatment at 5°C for 5 min, whereas only 55.5%

S. SAHA; T. OTOI; M. TAKAGI; A. BOEDIONO; C. SUMANTRI; T. SUZUKI

1996-01-01

256

Toxicogenomic responses of zebrafish embryos/larvae to tris(1,3-dichloro-2-propyl) phosphate (TDCPP) reveal possible molecular mechanisms of developmental toxicity.  

PubMed

Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is frequently present in indoor dust and can be detected in human milk. In order to evaluate the effects of TDCPP on vertebrate development, zebrafish embryos/larvae were used as an animal model to examine developmental phenotypes and explore possible mechanisms of toxicity by employing microarrays and iTRAQ labeling quantitative proteomics. The results demonstrated that treatment with TDCPP (3 ?M) from 0.75 h postfertilization (hpf) inhibited cell rearrangement at 4 hpf, caused delay in epiboly at 5.7 and 8.5 hpf, and led to abnormal development (e.g., short tail, reduced body size) and lethality between 14 and 45 hpf, which might be related with altered expression of genes regulating embryogenesis. Furthermore, trunk curvature was observed as the main phenotype in 96 hpf zebrafish larvae exposed to 1 or 3 ?M TDCPP, possibly by changing somite formation and expression of proteins related to fast muscle and cartilage development. Collectively, our results suggest that exposure to TDCPP causes developmental toxicity in vertebrates and warrant the need for studies to evaluate the potential health risks of TDCPP to developing human embryos/infants/children, due to its frequent presence in indoor dust and potential for human exposure. PMID:23919627

Fu, Jie; Han, Jian; Zhou, Bingsheng; Gong, Zhiyuan; Santos, Eduarda M; Huo, Xiaojing; Zheng, Weiling; Liu, Hongling; Yu, Hongxia; Liu, Chunsheng

2013-09-17

257

Miniaturized Embryo Array for Automated Trapping, Immobilization and Microperfusion of Zebrafish Embryos  

PubMed Central

Zebrafish (Danio rerio) has recently emerged as a powerful experimental model in drug discovery and environmental toxicology. Drug discovery screens performed on zebrafish embryos mirror with a high level of accuracy the tests usually performed on mammalian animal models, and fish embryo toxicity assay (FET) is one of the most promising alternative approaches to acute ecotoxicity testing with adult fish. Notwithstanding this, automated in-situ analysis of zebrafish embryos is still deeply in its infancy. This is mostly due to the inherent limitations of conventional techniques and the fact that metazoan organisms are not easily susceptible to laboratory automation. In this work, we describe the development of an innovative miniaturized chip-based device for the in-situ analysis of zebrafish embryos. We present evidence that automatic, hydrodynamic positioning, trapping and long-term immobilization of single embryos inside the microfluidic chips can be combined with time-lapse imaging to provide real-time developmental analysis. Our platform, fabricated using biocompatible polymer molding technology, enables rapid trapping of embryos in low shear stress zones, uniform drug microperfusion and high-resolution imaging without the need of manual embryo handling at various developmental stages. The device provides a highly controllable fluidic microenvironment and post-analysis eleuthero-embryo stage recovery. Throughout the incubation, the position of individual embryos is registered. Importantly, we also for first time show that microfluidic embryo array technology can be effectively used for the analysis of anti-angiogenic compounds using transgenic zebrafish line (fli1a:EGFP). The work provides a new rationale for rapid and automated manipulation and analysis of developing zebrafish embryos at a large scale.

Akagi, Jin; Khoshmanesh, Khashayar; Evans, Barbara; Hall, Chris J.; Crosier, Kathryn E.; Cooper, Jonathan M.; Crosier, Philip S.; Wlodkowic, Donald

2012-01-01

258

Toxicity Data On Elastomers and Plastics Based On LC50 Using Dome Chamber Test  

Microsoft Academic Search

The dome chamber toxicity test has been ex tensively used in the evaluation of elastomers and plastics. Much of the published data has been based on time-to- response measurements. Relative toxicity data based on LC50 measurements using the dome chamber toxicity test are presented. These data provide a measure of potency of toxic effects, in contrast to the measure of

Carlos J. Hilado; Patricia A. Huttlinger

1982-01-01

259

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

Federal Register 2010, 2011, 2012, 2013

...1) (CAS No. 127-68-4). reactive dyeing; Reproductive/ assistant in discharge Developmental Toxicity printing; viscosity Screening Test; control agent in Characterization Study; cosmetics; oxidizing Validation of Analytical agent in...

2013-11-06

260

Fluorescent cell-based sensing approaches for toxicity testing  

Microsoft Academic Search

Fluorimetric cell-based sensing methods have attracted increasing interest in toxicity testing of pharmaceuticals, pathogens,\\u000a environmental pollutants, and other chemicals. The objective of this review is to summarise the variety of approaches reported\\u000a up to now and to present recent developments in this area. The different approaches are described in relation to their underlying\\u000a mechanism and, especially, to the role of

Michael Fritzsche; Carl-Fredrik Mandenius

2010-01-01

261

Produced water toxicity tests accurately measure the produced water toxicity in marine environments?  

SciTech Connect

U.S. Environmental Protection Agency (EPA) Region VI has issued a general permit for offshore oil and gas discharges to the Gulf of Mexico that places numerical limits on whole effluent toxicity (WEI) for produced water. Recently proposed EPA general permits for other produced water discharges in Regions VI and X also include enforceable numerical limits on WET. Clearly, the industry will be conducting extensive produced water WET testing. Unfortunately, the WET test may not accurately measure the toxicity of the chemical constituents of produced water. Rather the mortality of test organisms may be attributable to (1) the high salinity of produced water, which causes salinity shock to the organisms, or (2) an ionic imbalance caused by excesses or deficiencies of one or more of seawater`s essential ions in the test chambers. Both of these effects are likely to be mitigated in actual offshore discharge settings, where the receiving water will be seawater and substantial dilution will be probable. Thus, the additional salinity of produced water will be rapidly assimilated, and the proper marine ionic balance will be quickly restored. Regulatory authorities should be aware of these factors when interpreting WET test results.

Douglas, W.S. [Aqua Survey, Inc., Flemington, NJ (United States); Veil, J.A. [Argonne National Lab., Washington, DC (United States)

1996-10-01

262

Field assessments in conjunction with whole effluent toxicity testing  

SciTech Connect

Whole effluent toxicity (WET) tests are widely used to assess potential effects of wastewater discharges on aquatic life. This paper represents a summary of chapters in a 1996 Society of Environmental Toxicology and Chemistry-sponsored workshop and a literature review concerning linkages between WET testing and associated field biomonitoring. Most published studies thus far focus primarily on benthic macroinvertebrates and on effluent-dominated stream systems in which effluents demonstrate little or no significant acute toxicity. Fewer studies examine WET test predictability in other aquatic ecosystems (e.g., wetlands, estuaries, large rivers) or deal with instream biota such as fish and primary producers. Published results indicate that standards for the usual WET freshwater test species, Ceriodaphnia dubia and Pimephales promelas, may not always protect most of the species inhabiting a receiving stream. Although WET tests are useful in predicting aquatic individual responses, they are not meant to directly measure natural population or community responses. Further, they do not address bioconcentration or bioaccumulation of hydrophobic compounds; do not assess eutrophication effects in receiving systems; and lastly, do not reflect genotoxic effects or function to test for endocrine-disrupting chemicals. Consequently, a more direct evaluation of ecosystem health, using bioassessment techniques, may be needed to properly evaluate aquatic systems affected by wastewater discharges.

La Point, T.W.; Waller, W.T.

2000-01-01

263

Toxicity Testing in the 21st Century: A Vision and a Strategy  

Microsoft Academic Search

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 usage by transitioning from current expensive and lengthy in vivo testing with qualitative

Daniel Krewski; Daniel Acosta Jr; Melvin Andersen; Henry Anderson; John C. Bailar III; Kim Boekelheide; Robert Brent; Gail Charnley; Vivian G. Cheung; Sidney Green Jr; Karl T. Kelsey; Nancy I. Kerkvliet; Abby A. Li; Lawrence McCray; Otto Meyer; Reid D. Patterson; William Pennie; Robert A. Scala; Gina M. Solomon; Martin Stephens; James Yager; Lauren Zeise

2010-01-01

264

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

EPA Science Inventory

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....

265

Integral toxicity test of sea waters by an algal biosensor.  

PubMed

An integral toxicity test, based on an algal biosensor and suitable to be used in sea water, is presented. The biosensor was designed and built by coupling a Clark oxygen electrode as transducer and the marine alga Spirulina subsalsa as biological mediator; it constitutes the "core" in a lab-scale prototype of a flow apparatus suitable to continuously monitor, in sea water, the photosynthetic activity of the alga and, from its variation, the marine pollution from the toxicological point of view. Inorganic pollutants (heavy metals) were tested in previous researches while organic ones (chlorophenols, pesticides and surfactants) are the object of the present paper. PMID:12073894

Tonnina, Daniele; Campanella, Luigi; Sammartino, Maria Pia; Visco, Giovanni

2002-04-01

266

Study of Charge-Dependent Transport and Toxicity of Peptide-Functionalized Silver Nanoparticles Using Zebrafish Embryos and Single Nanoparticle Plasmonic Spectroscopy  

PubMed Central

Nanomaterials possess unusually high surface area-to-volume ratios, and surface-determined physicochemical properties. It is essential to understand their surface-dependent toxicity in order to rationally design biocompatible nanomaterials for a wide variety of applications. In this study, we have functionalized the surfaces of silver nanoparticles (Ag NPs, 11.7 ± 2.7 nm in diameters) with three biocompatible peptides (CALNNK, CALNNS, CALNNE) to prepare positively (Ag-CALNNK NPs+?), negatively (Ag-CALNNS NPs?2?), and more negatively charged NPs (Ag-CALNNE NPs?4?), respectively. Each peptide differs in a single amino acid at its C-terminus, which minimizes the effects of peptide sequences and serves as a model molecule to create positive, neutral and negative charges on the surface of the NPs at pH 4–10. We have studied their charge-dependent transport into early-developing (cleavage-stage) zebrafish embryos and their effects on embryonic development using dark-field optical microscopy and spectroscopy (DFOMS). We found that all three Ag-peptide NPs passively diffused into the embryos via their chorionic pore canals, and stayed inside the embryos throughout their entire development (120 h), showing charge-independent diffusion modes and charge-dependent diffusion coefficients. Notably, the NPs create charge-dependent toxic effects on embryonic development, showing that the Ag-CALNNK NPs+? (positively charged) are the most biocompatible while the Ag-CALNNE NPs–4? (more negatively charged) are the most toxic. By comparing with our previous studies of the same sized citrated Ag and Au NPs, the Ag-peptide NPs are much more biocompatible than the citrated Ag NPs, and nearly as biocompatible as the Au NPs, showing the dependence of nanotoxicity upon the surface charges, surface functional groups and chemical compositions of the NPs. This study also demonstrates powerful applications of single NP plasmonic spectroscopy for quantitative analysis of single NPs in vivo and in tissues, and reveals the possibility of rational design of biocompatible NPs.

Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Xu, Xiao-Hong Nancy

2013-01-01

267

[Microbial test combination with Vibrio fischeri as a screening toxicity test  

PubMed

Two different microbial toxicity tests were investigated concerning the possibility to reduce animal experiments in product testing. In the acute bioluminescence test the inhibition of the bacterial luminescence was measured. In the chronic DMS test the inhibition of the microbial metabolism of DMSO to DMS was recorded. The combination of both tests with the same organism Vibrio fischeri enhances the power as a toxicological indicator. We used well known alcohols and tensides. For 15 substances, the correlation between the experimental results and the Draize eye irritation test (rs = 0,943) and the intravenous toxicity (rs = 0,958) was statistically significant. If both tests gave EC50-values >10000mg/L, the substance could be categorised as non or mild toxic. If the EC50-values were <5mg/L, an extremely toxic substance could be expected. Neither false positive nor false negative results have been found, therefore the application of the method as a screening test or as a part in a test battery is conceivable. PMID:11178509

Schicktanz, Silke; Frahne, Dietrich; Honnen, Wolfgang; Müller, Ewald

1998-01-01

268

Organotypic liver culture models: Meeting current challenges in toxicity testing  

PubMed Central

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

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

2012-01-01

269

Tritium toxicity: age-dependent radiosensitivity of mouse testes  

SciTech Connect

As a radiation hazard of biological significance tritium has largely been ignored because of its rapid turnover from the body, its low average beta energy, and short range in the tissue. In all the available reports of the investigations, little research effort has been noticed on the age-specific consequences of HTO-irradiation of mammals in the perinatal to pubertal stages of life as compared to the adult stages. The present study is an attempt to evaluate qualitative and quantitatively the age dependent radio-sensitivity of mice testes to tritium toxicity.

Bhatia, A.L.

1985-06-01

270

A large hemispherical chamber for fire toxicity tests  

NASA Technical Reports Server (NTRS)

The paper describes an 84-liter chamber for fire toxicity tests consisting of an upper hemispherical dome section with a diameter of 533 mm, made of clear polymethyl methacrylate and a lower cylindrical base section 190 mm deep, made of cast aluminum. The chamber is designed to expose 36 mice, 8 rats, 4 rabbits or combinations of smaller numbers of two or three species simultaneously to the gaseous products of pyrolysis or combustion. The chamber does not appear to be suitable for screening purposes because its large size introduces operating costs and problems which reduce its cost effectiveness.

Hilado, C. J.; Smouse, K. Y.; Leon, H. A.

1976-01-01

271

VALIDATION OF EMBRYO TESTS FOR DETERMINING EFFECTS OF FUNGAL PEST CONTROL AGENTS ON NONTARGET AQUATIC ANIMALS  

EPA Science Inventory

Developing embryos of the inland silverside fish Menidia beryllina and grass shrimp Palaemonetes pugio were exposed to conidiospores of the fungal weed control agent, Colletotrichum gloeosporioides, f. sp. aeschynomene, and the entomopathogen, Metarhizium anisopliae. nly Metarhiz...

272

Chronic toxicity bioassay with ceriodaphnia dubia': (1) An evaluation of a toxicity test-based approach for determining the sources of chronic toxicity; and (2) an evaluation of culture\\/dilution waters and diet as determinants of test outcomes  

Microsoft Academic Search

In order to limit the discharge of toxic materials in toxic amounts to the waterways of the United States, the U. S. Environmental Protection Agency (EPA) has developed a 7-day survival and reproduction toxicity bioassay test using the freshwater cladoceran, Ceriodaphnia dubia. The North Carolina Division of Environmental Management has developed a less expensive modification of this test called the

D. E. Francisco; M. C. Elias; C. A. LaRocca; F. A. DiGiano; M. J. Maerker

1993-01-01

273

PHOTOACTIVATED POLYCYCLIC AROMATIC HYDROCARBON TOXICITY IN MEDAKA (ORYZIAS LATIPES) EMBRYOS: RELEVANCE TO ENVIRONMENTAL RISK IN CONTAMINATED SITES  

EPA Science Inventory

The hazard for photoactivated toxicity of polycyclic aromatic hydrocarbons (PAHs) has been clearly demonstrated; however, to our knowledge, the risk in contaminated systems has not been characterized. To address this question, a median lethal dose (LD50) for fluoranthene photoa...

274

FISH SUBCHRONIC TOXICITY PREDICTION MODEL FOR INDUSTRIAL ORGANIC CHEMICALS THAT PRODUCE NARCOSIS  

EPA Science Inventory

A model based on partition coefficient was developed for predicting subchronic toxicities of selected chemicals to fish. Early life stage tests were conducted under flow-through conditions using fathead minnows (Pimephales promelas) as test organisms. Embryos, larvae and juvenile...

275

Potential effects of food addition to sediment on test conditions in sediment toxicity tests  

Microsoft Academic Search

Purpose  Standardized sediment toxicity assays often employ periodic additions of uncontaminated food to sustain energy and growth\\u000a requirements of the test organisms. Consequently, selective feeding on this uncontaminated food may reduce exposure to sediment\\u000a particles containing the test substance. To address this issue, some standard guidelines propose to add food to the sediment\\u000a before spiking with the test substance to account

Philipp Egeler; Kevin S. Henry; Caroline Riedhammer

2010-01-01

276

AN ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) TESTING OF SEVEN TECHNOLOGIES DETECTING TOXICITY IN DRINKING WATER (R2)  

EPA Science Inventory

Rapid toxicity technologies can detect certain toxins and with testing it can be determined their susceptibility to interfering chemical in controlled experimental matrix. Rapid toxicity technologies do not identify or determine the concentrations of specific contaminants, but s...

277

An interlaboratory comparison of sediment elutriate preparation and toxicity test methods  

EPA Science Inventory

Elutriate bioassays are among numerous methods that exist for assessing the potential toxicity of sediments in aquatic systems. In this study, interlaboratory results were compared from 96-hour Ceriodaphnia dubia and Pimephales promelas static-renewal acute toxicity tests conduct...

278

Toxicity of lead and zinc to developing mussel and sea urchin embryos: critical tissue residues and effects of dissolved organic matter and salinity.  

PubMed

Lead (Pb) EC50 values in the very sensitive early development phases (48-72h post-fertilization) of the mussels Mytilus galloprovincialis and Mytilus trossolus and sea urchin Strongylocentrotus purpuratus in 100% sea water were: M. trossolus - 45 (95% C.I.=22-72) ?gL(-1); M. galloprovincialis - 63 (36-94) ?gL(-1); S. purpuratus - 74 (50-101) ?gL(-1). Salinity thresholds for normal development varied: M. trossolus>21ppt; M. galloprovincialis>28ppt; S. purpuratus?30ppt. Addition of two spectroscopically distinct dissolved organic matters (DOM) from fresh water (Nordic Reservoir) and sea water (Inshore) moderately decreased the toxicity of Pb to both mussels, but not in a concentration-dependent fashion, with only an approximate doubling of EC50 over the range of 1.4-11.2mgCL(-1). Independent Pb binding capacity determinations for DOC explained the lack of a relationship between DOM concentration and toxicity. Salinity had no effect on Pb toxicity down to 21ppt in M. trossolus, and low salinity (21ppt) did not enhance the protective effect of DOC. Both DOMs increased the toxicity of Pb in developing sea urchin embryos, in contrast to mussels. Relative to Pb, the organisms were 6-9 fold less sensitive to Zn on a molar basis in 100% seawater with the following Zn EC50s: M. trossolus - 135 (103-170) ?gL(-1); M. galloprovincialis - 172 (126-227) ?gL(-1), S. purpuratus - 151 (129-177) ?gL(-1). Nordic Reservoir and Inshore DOM (2-12mgCL(-1)) had no significant effect on Zn toxicity to mussels, in accord with voltammetry data showing an absence of any strong ligand binding for Zn by DOMs. As with Pb, DOMs increased Zn toxicity to urchin larvae. Critical Tissue Residues (CTR) based on whole body concentrations of Pb and Zn were determined for M. galloprovincialis at 48h and S. purpuratus at 72h. The median lethal CTR values (LA50s), useful parameters for development of saltwater Biotic Ligand Models (BLMs), were approximately 4-fold higher on a molar basis for Zn than for Pb. The latter were not altered by DOM exposure, despite increased EC50 values, in accord with the tenets of the BLM. PMID:23603691

Nadella, Sunita R; Tellis, Margaret; Diamond, Rachael; Smith, Scott; Bianchini, Adalto; Wood, Chris M

2013-08-01

279

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2011 CFR

...treatments. The solvent should not be toxic or have an effect on the toxicity of the...stainless steel, and perfluorocarbon plastic should be used wherever possible. Concrete, fiberglass, or plastic (e.g., PVC) may be used for...

2011-07-01

280

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2012 CFR

...treatments. The solvent should not be toxic or have an effect on the toxicity of the...stainless steel, and perfluorocarbon plastic should be used wherever possible. Concrete, fiberglass, or plastic (e.g., PVC) may be used for...

2012-07-01

281

Combined repeated-dose toxicity study of silver nanoparticles with the reproduction/developmental toxicity screening test.  

PubMed

Combined repeated-dose toxicity study of citrate-capped silver nanoparticles (7.9 ± 0.95 nm) with reproduction/developmental toxicity was investigated in rats orally treated with 62.5, 125 and 250 mg/kg, once a day for 42 days for males and up to 52 days for females. The test was performed based on the Organization for Economic Cooperation and Development test guideline 422 and Good Laboratory Practice principles. No death was observed in any of the groups. Alopecia, salivation and yellow discolouration of the lung were observed in a few rats but the symptoms were not dose-dependent. Haematology, serum biochemical investigation and histopathological analysis revealed no statistically significant differences between control group and the treated groups. Toxicity endpoints of reproduction/developmental screening test including mating, fertility, implantation, delivery and foetus were measured. There was no evidence of toxicity. PMID:23432083

Hong, Jeong-Sup; Kim, Suhyon; Lee, Sang Hee; Jo, Eunhye; Lee, Byungcheun; Yoon, Junheon; Eom, Ig-Chun; Kim, Hyun-Mi; Kim, Pilje; Choi, Kyunghee; Lee, Moo Yeol; Seo, Yeong-Rok; Kim, Younghun; Lee, Yeonjin; Choi, Jonghye; Park, Kwangsik

2014-06-01

282

Cryopreservation of primordial germ cells by rapid cooling of whole zebrafish (Danio rerio) embryos.  

PubMed

The feasibility of cryopreservation of zebrafish (Danio rerio) primordial germ cells (PGCs) by rapid cooling (i.e., vitrification) of dechorionated whole embryos at the 14- to 20-somite stage was investigated. Initially, we examined the glass-forming properties and embryo toxicities of six cryoprotectants: methanol (MeOH), ethylene glycol (EG), glycerol (GC), dimethyl sulfoxide (DMSO), propylene glycol (PG) and 1,3-butylene glycol (1,3-BG). According to the results of glass-forming and embryo toxicity tests, pretreatment solution (PS) containing 2 or 3 M cryoprotectant and vitrification solution (VS) containing 5 M cryoprotectant and 0.5 M sucrose were prepared using each cryoprotectant. Dechorionated embryos, the PGCs of which were visualized by injection of green fluorescence protein-nos1 3'UTR mRNA, were cooled rapidly by plunging into liquid nitrogen after serial exposure to PS and VS. All embryos cooled with MeOH, PG and 1,3-BG showed ice formation during cooling, and few embryos had live PGCs after warming. Most embryos cooled with GC did not show ice formation; however, few embryos had live PGCs. All embryos cooled with EG and most embryos cooled with DMSO had live PGCs when the embryos did not show ice formation during cooling. Based on the number of live PGCs in fresh embryos, the maximum survival rates of PGCs recovered from embryos cooled with EG and DMSO were estimated to be about 40 and 20%, respectively. The present study indicates that rapid cooling of dechorionated whole embryos, especially using EG-based solutions, could be utilized as a simple and promising tool for cryopreservation of PGCs. PMID:19996550

Higaki, Shogo; Mochizuki, Kentaro; Akashi, Yuichiro; Yamaha, Etsuro; Katagiri, Seiji; Takahashi, Yoshiyuki

2010-04-01

283

Quantification and in situ localisation of abcb1 and abcc9genes in toxicant-exposed sea urchin embryos.  

PubMed

A multixenobiotic resistance (MXR) mechanism mediated by ABC binding cassette (ABC) transport proteins is an efficient chemical defence mechanism in sea urchin embryos. The aim of our work was to evidence whether exposure to sub-lethal doses of specific contaminants (oxybenzone (OXI), mercuric chloride (HgCl2) and trybutiltin (TBT)) would induce MXR transporter activity during embryonic development (from zygote to blastula stage) in purple sea urchin (Paracentrotus lividus) embryos. Further, we present data on molecular identification, transport function, expression levels and gene localisation of two ABC efflux transporters-P-glycoprotein (ABCB1/P-gp) and sulfonylurea-receptor-like protein (ABCC9/SUR-like). Partial cDNA sequences of abcb1 and abcc9 were identified and quantitative PCR (qPCR) evidenced an increase in mRNA transcript levels of both ABC transporters during the two-cell, as well as an overall decrease during the blastulae stage. Calcein-AM efflux activity assay indicated the activation of multidrug resistance-associated protein/ABCC-like transport in the presence of HgCl2 and TBT in exposed blastulae. The in situ hybridisation of the two-cell and blastula stages showed ubiquitous localisation of both transcripts within cells, supporting qPCR data. In conclusion, ABCB1 and ABCC9 are constitutive, as are HgCl2, TBT and OXI-inducible ABC membrane transporters, coexpressed in the zygote, two-cell and blastula stages of the P. lividus. Their ubiquitous cell localisation further fortifies their protective role in early embryonic development. PMID:23690080

Bošnjak, Ivana; Plei?, Ivana Lepen; Borra, Marco; Mladineo, Ivona

2013-12-01

284

EFFECT OF CHEMICAL CARRIERS ON AVIAN LC(50) TOXICITY TESTS  

EPA Science Inventory

The subacute dietary (LC50) toxicity of a pesticide as prescribed by the Federal Insecticide Fungicide and Rodenticide Act and of toxic substances as defined by the Toxic Substances Control Act is a routine data point for many chemicals. The methods under which the LC50 data are ...

285

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

Federal Register 2010, 2011, 2012, 2013

...149-44- Biodegration Test agent for textiles, 0). according to OECD 301B: bleaching agent for Degradation of a Product. molasses, soap. 2. Existing study for Acute Toxicity to Fish According to DIN Method 38412. 3. Existing study for Acute...

2011-06-29

286

Silver speciation during chronic toxicity tests with the mysid, Americamysis bahia  

Microsoft Academic Search

A 28-day chronic toxicity test and two 7-day chronic estimation toxicity tests were conducted with silver nitrate (AgNO3) and the marine invertebrate, Americamysisbahia, in 20‰ (parts-per thousand) salinity seawater. One 7-day test was initiated with 7-day-old mysids and the second was initiated with <24-h-old mysids. There was very good agreement between the three toxicity tests. The no-observed-effect concentration (NOEC) values

Timothy J. Ward; James R. Kramer

2002-01-01

287

Reproducibility of a life-cycle toxicity test with Daphnia magna  

SciTech Connect

Standardized chronic life-cycle toxicity testing procedures for aquatic species are described. The reproducibility of chronic toxicity and points using the static-renewal method with Daphnia magna are investigated. The objectives were to determine if the lowest rejected concentrations tested (LRCTs) obtained for six different toxicity criteria in static-renewal tests with acridine were reproducible over time and to determine the relative sensitivity and variability of the toxicity criteria. Two of the six toxicity criteria, numbers of young per brood and the young produced per female, were found to be reliable and sensitive for estimating the LRCT for acridine to D. magna. (RJC)

Parkhurst, B.R.; Forte, J.L.; Wright, G.P.

1981-01-01

288

KEPONE (TRADEMARK): CHRONIC EFFECTS ON EMBRYO, FRY, JUVENILE, AND ADULT SHEEPSHEAD MINNOWS ('CYPRINODON VARIEGATUS')  

EPA Science Inventory

The report discusses the toxicity of Kepone to, and uptake by embryo, fry, juvenile, and adult sheepshead minnows (Cyprinodon variegatus) using intermittent-flow toxicity tests. Concentrations of Kepone and percentage of adult fish surviving in a 28-day exposure were--Control, 95...

289

Large-Scale Assessment of the Zebrafish Embryo as a Possible Predictive Model in Toxicity Testing  

Microsoft Academic Search

BackgroundIn the drug discovery pipeline, safety pharmacology is a major issue. The zebrafish has been proposed as a model that can bridge the gap in this field between cell assays (which are cost-effective, but low in data content) and rodent assays (which are high in data content, but less cost-efficient). However, zebrafish assays are only likely to be useful if

Shaukat Ali; Harald G. J. Van Mil; Michael K. Richardson; Ferenc Mueller

2011-01-01

290

Chronic Toxicity Bioassay with 'Ceriodaphnia dubia': (1) an Evaluation of a Toxicity Test-Based Approach for Determining the Sources of Chronic Toxicity; and (2) an Evaluation of Culture/Dilution Waters and Diet as Determinants of Test Outcomes.  

National Technical Information Service (NTIS)

In order to limit the discharge of toxic materials in toxic amounts to the waterways of the United States, the U. S. Environmental Protection Agency (EPA) has developed a 7-day survival and reproduction toxicity bioassay test using the freshwater cladocer...

D. E. Francisco M. C. Elias C. A. LaRocca F. A. DiGiano M. J. Maerker

1993-01-01

291

Custom-designed nanomaterial libraries for testing metal oxide toxicity.  

PubMed

Advances in aerosol technology over the past 10 years have enabled the generation and design of ultrafine nanoscale materials for many applications. A key new method is flame spray pyrolysis (FSP), which produces particles by pyrolyzing a precursor solution in the gas phase. FSP is a highly versatile technique for fast, single-step, scalable synthesis of nanoscale materials. New innovations in particle synthesis using FSP technology, including variations in precursor chemistry, have enabled flexible, dry synthesis of loosely agglomerated, highly crystalline ultrafine powders (porosity ? 90%) of binary, ternary, and mixed-binary-and-ternary oxides. FSP can fulfill much of the increasing demand, especially in biological applications, for particles with specific material composition, high purity, and high crystallinity. In this Account, we describe a strategy for creating nanoparticle libraries (pure or Fedoped ZnO or TiO?) utilizing FSP and using these libraries to test hypotheses related to the particles' toxicity. Our innovation lies in the overall integration of the knowledge we have developed in the last 5 years in (1) synthesizing nanomaterials to address specific hypotheses, (2) demonstrating the electronic properties that cause the material toxicity, (3) understanding the reaction mechanisms causing the toxicity, and (4) extracting from in vitro testing and in vivo testing in terrestrial and marine organisms the essential properties of safe nanomaterials. On the basis of this acquired knowledge, we further describe how the dissolved metal ion from these materials (Zn²? in this Account) can effectively bind with different cell constituents, causing toxicity. We use Fe-S protein clusters as an example of the complex chemical reactions taking place after free metal ions migrate into the cells. As a second example, TiO? is an active material in the UV range that exhibits photocatalytic behavior. The induction of electron-hole (e?/h?) pairs followed by free radical production is a key mechanism for biological injury. We show that decreasing the bandgap energy increases the phototoxicity in the presence of near-visible light. We present in detail the mechanism of electron transfer in biotic and abiotic systems during light exposure. Through this example we show that FSP is a versatile technique for efficiently designing a homologous library, meaning a library based on a parent oxide doped with different amounts of dopant, and investigating the properties of the resulting compounds. Finally, we describe the future outlook and state-of-the-art of an innovative two-flame system. A double-flame reactor enables independent control over each flame, the nozzle distances and the flame angles for efficient mixing of the particle streams. In addition, it allows for different flame compositions, flame sizes, and multicomponent mixing (a grain-grain heterojunction) during the reaction process. PMID:23194152

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

2013-03-19

292

Test of significant toxicity: a statistical application for assessing whether an effluent or site water is truly toxic.  

PubMed

The U.S. Environmental Protection Agency (U.S. EPA) and state agencies implement the Clean Water Act, in part, by evaluating the toxicity of effluent and surface water samples. A common goal for both regulatory authorities and permittees is confidence in an individual test result (e.g., no-observed-effect concentration [NOEC], pass/fail, 25% effective concentration [EC25]), which is used to make regulatory decisions, such as reasonable potential determinations, permit compliance, and watershed assessments. This paper discusses an additional statistical approach (test of significant toxicity [TST]), based on bioequivalence hypothesis testing, or, more appropriately, test of noninferiority, which examines whether there is a nontoxic effect at a single concentration of concern compared with a control. Unlike the traditional hypothesis testing approach in whole effluent toxicity (WET) testing, TST is designed to incorporate explicitly both ? and ? error rates at levels of toxicity that are unacceptable and acceptable, given routine laboratory test performance for a given test method. Regulatory management decisions are used to identify unacceptable toxicity levels for acute and chronic tests, and the null hypothesis is constructed such that test power is associated with the ability to declare correctly a truly nontoxic sample as acceptable. This approach provides a positive incentive to generate high-quality WET data to make informed decisions regarding regulatory decisions. This paper illustrates how ? and ? error rates were established for specific test method designs and tests the TST approach using both simulation analyses and actual WET data. In general, those WET test endpoints having higher routine (e.g., 50th percentile) within-test control variation, on average, have higher method-specific ? values (type I error rate), to maintain a desired type II error rate. This paper delineates the technical underpinnings of this approach and demonstrates the benefits to both regulatory authorities and permitted entities. PMID:21305584

Denton, Debra L; Diamond, Jerry; Zheng, Lei

2011-05-01

293

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

PubMed

Prior to introduction to the clinic, pharmaceuticals must undergo rigorous toxicity testing to ensure their safety. Traditionally, this has been achieved using in vivo animal models. However, besides ethical reasons, there is a continual drive to reduce the number of animals used for this purpose due to concerns such as the lack of concordance seen between animal models and toxic effects in humans. Adequate testing to ensure any toxic metabolites are detected can be further complicated if the agent is administered in a prodrug form, requiring a source of cytochrome P450 enzymes for metabolism. A number of sources of metabolic enzymes have been utilised in in vitro models, including cell lines, primary human tissue and liver extracts such as S9. This review examines current and new in vitro models for toxicity testing, including a new model developed within the authors' laboratory utilising HepG2 liver spheroids within a co-culture system to examine the effects of chemotherapeutic agents on other cell types. PMID:19839229

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

2009-01-01

294

Interlaboratory variability of amphipod sediment toxicity tests in a cooperative regional monitoring program.  

PubMed

Marine sediment toxicity tests are widely applied in monitoring programs, yet relatively little is known about the comparability of data from different laboratories. The need for comparability information is increased in cooperative monitoring programs, where multiple laboratories (often with variable skill levels) perform toxicity tests. An interlaboratory comparison exercise was conducted among seven laboratories in order to document the comparability of sediment toxicity measurements during the Bight '98 regional sediment survey in southern California. Sediments from four stations in Los Angeles and Long Beach Harbors were tested using a 10-day survival test of the amphipod Eohaustorius estuarius. All laboratories successfully performed the sediment test and associated reference toxicant test. Statistically significant differences were found in mean amphipod survival rates among some laboratories for the field-collected sediments, but there was little evidence of a consistent bias among laboratories. Although the reference toxicant test indicated a five-fold variation in test sensitivity among laboratories, these results were not accurate predictors of interlaboratory performance for the sediment tests. The laboratories demonstrated excellent concordance (Kendall's W = 0.91) in ranking the field-collected sediments by toxicity. Agreement on classifying the sediments into categories (nontoxic, moderately toxic, and highly toxic) based upon the percent of survival was best for highly toxic sediments. An analysis of test precision based upon the variance among replicates within a test indicated that the measured survival rate for a sample may vary by up to 12 percentage points from the actual response. PMID:12620020

Bay, Steven M; Jirik, Andrew; Asato, Stanford

2003-01-01

295

Results of acute and chronic toxicity tests conducted at SRS NPDES outfalls, July--October 1991  

SciTech Connect

Acute (48 hour LC50) and chronic (7-day reproductive impairment) toxicity tests were conducted on Ceriodaphnia dubia in water collected from 53 NPDES outfalls. All tests were conducted at the in-stream waste concentration. only 12 of the 53 outfalls showed no evidence of toxicity. Twenty-eight of the outfalls were acutely toxic, often producing 100% mortality during the first day of exposure. Fourteen outfalls had no discharge at the time of sampling and could not be tested. Three outfalls were not tested because their toxicity has been adequately characterized in other investigations. Elevated concentrations of total residual chlorine are suspected to be responsible for the observed toxicity of many NPDES outfalls, particularly the sanitary wastewater treatment plants. Chemical data from previous studies indicate that metals may also be present in toxic concentrations at many outfalls. Toxicity identification and reduction options are discussed.

Specht, W.L.

1992-01-01

296

Comparison of techniques for the isolation of sediment pore water for toxicity testing  

Microsoft Academic Search

The objective of this study was to define an interstitial (pore) water isolation technique suitable for sediment toxicity testing and toxicity identification evaluation (TIE) research. Pore water was prepared from sediments collected at two fresh-water sites (Saginaw River, Keweenaw Waterway) using four or five different techniques, and the samples were compared with respect to toxicity to Ceriodaphnia dubia and several

G. T. Ankley; M. K. Schubauer-Berigan

1994-01-01

297

STATISTICAL APPROACH TO PREDICTING CHRONIC TOXICITY OF CHEMICALS TO FISHES FROM ACUTE TOXICITY TEST DATA  

EPA Science Inventory

A comprehensive approach to predicting chronic toxicity from cute toxicity data was developed in which simultaneous onsideration is given to concentration, degree of response, and ime course of effect. onsistent endpoint (lethality) and degree of response (0 percent) were used to...

298

INTRODUCTION TO A DISCUSSION OF THE USE OF AQUATIC TOXICITY TESTS FOR EVALUATION OF THE EFFECTS OF TOXIC SUBSTANCES  

EPA Science Inventory

A variety of classes of aquatic toxicity tests are presented and discussed in relation to their ability to provide useful estimates of the environmental effects of chemicals or discharges. These classes of tests can be judged and compared numerically by several standards: ability...

299

REVIEW OF THE CURRENT STATUS OF MARINE ALGAL TOXICITY TESTING IN THE UNITED STATES  

EPA Science Inventory

Algal toxicity testing is not new, but only within the past few years have data from such testing been used to help set standards for allowable contamination. arly toxicity testing with marine algae used a few planktonic species with inhibition of growth as the primary endpoint. ...

300

Toxicity testing moves from the legislature to the petri dish-and back.  

PubMed

With the growing cost of using animals to test the safety of new chemicals and an increasing backlog of chemicals awaiting testing, the quest for cell-based in vitro alternatives for toxicity testing is gaining momentum. PMID:18724925

Gura, Trisha

2008-08-22

301

Scientific Rationale for the Selection of Toxicity Testing Methods: Human Health Assessment.  

National Technical Information Service (NTIS)

This document is the first of a two-part literature analysis of parameters associated with the various toxicity testing methods (test animal selection, pathology requirements, etc.). Acute, subchronic, chronic, and carcinogenic testing methods are covered...

R. H. Ross, M. G. Ryon, M. W. Daugherty, J. S. Drury, J. T. Ensminger

1980-01-01

302

International Study on Artemia. Nutritional Effects in Toxicity Tests: Use of Different Artemia Geographical Strains.  

National Technical Information Service (NTIS)

A series of experiments was conducted to determine whether feeding marine organisms different geographical strains of Artemia prior to or during a toxicity test could significantly alter the results of the test. In each experiment, the test organisms were...

D. A. Bengtson A. D. Beck S. M. Lussier D. Migneault C. E. Olney

1984-01-01

303

Lethal and sublethal toxicity of the industrial chemical epichlorohydrin on Rhinella arenarum (Anura, Bufonidae) embryos and larvae.  

PubMed

Lethal and sublethal toxicity of the major chemical used in epoxide compounds, epichlorohydrin (ECH) was evaluated on the early life cycle of the common South American toad, Rhinella arenarum (Anura, Bufonidae). The stages evaluated were (according to Del Conte and Sirlin): early blastula (S.3-S.4), gastrula (S.10-S.12), rotation (S.15), tail bud (S.17), muscular response (S.18), gill circulation (S.20), open mouth (S.21), opercular folds (S.23) and complete operculum (S.25). The LC50 and EC50 values for lethal and sublethal effects were calculated. The early blastula was the most sensitive stage to ECH both for continuously and pulse-exposures (LC50-24h=50.9 mg L(-1)), while S.20 was the most resistant (LC50-24h=104.9 mg L(-1)). Among sublethal effects, early blastula was also the most sensitive stage (LOEC-48 h=20 mg L(-1)) and it has a Teratogenic Index of 2.5, which indicates the teratogenic potential of the substance. The main abnormalities were persistent yolk plugs, cell dissociation, tumors, hydropsy, oral malformations, axial/tail flexures, delayed development and reduced body size. ECH also caused neurotoxicity including scarce response to stimuli, reduction in the food intake, general weakness, spasms and shortening, erratic or circular swimming. Industrial contamination is considered an important factor on the decline of amphibian populations. Considering the available information about ECH's toxicity and its potential hazard to the environment, this work shows the first results of its developmental toxicity on a native amphibian species, Rhinella arenarum. PMID:24231313

Hutler Wolkowicz, Ianina R; Aronzon, Carolina M; Pérez Coll, Cristina S

2013-12-15

304

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

Federal Register 2010, 2011, 2012, 2013

...vinylic systems; antistatic Toxicity to Fish; Acute (1:1) (CAS No. 52556-42-0). properties; promotes Toxicity to Daphnia; adhesion of pigments; Toxicity to Algae; Acute emulsion polymerization in Inhalation Toxicity in paper, textile,...

2013-11-19

305

The enhancement of the subacute repeat dose toxicity test OECD TG 407 for the detection of endocrine active chemicals: comparison with toxicity tests of longer duration  

Microsoft Academic Search

The OECD conventional 28-day repeat dose toxicity test (OECD TG 407) is widely employed in the initial hazard identification\\u000a and characterization for commercial chemicals. The OECD has recently undertaken an international effort to “enhance” the conventional\\u000a 28-day repeat dose toxicity test (OECD TG 407) in order to ensure that chemicals acting through (anti)estrogenic, (anti)androgenic,\\u000a and (anti)thyroid mechanisms are identified. The

Heinz-Peter Gelbke; Andreas Hofmann; J. William Owens; Alexius Freyberger

2007-01-01

306

Comparison of mathematically-predicted toxic equivalents (TEQs) and bioassay-derived dioxin-equivalents (TCDD-EQs) in heron embryos  

USGS Publications Warehouse

Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from an uncontaminated site (Chincoteague National Wildlife Refuge,VA) and three polluted sites (Cat Island, Green Bay, WI; Bair and West Marin Islands, San Francisco Bay, CA). Hepatic microsomal monooxygenases were induced up to 85-fold relative to the reference site, and was associated with concentrations of total PCBs and 11 PCB congeners that are presumed to concern.to express toxicity through the Ah receptor. TEQs [mathematically predicted; summed product of PCB congener concentrations using 5 different sets of toxic equivalency factors (TEFs)] were compared to TCDD-EQs [derived by bioassay; ethoxyresorufin-O-dealkylase activity of treated H411E rat hepatoma cells]. Although TEQs were up to 15-fold greater than TCDD-EQs, the pattern among sites was consistent and TEQs were highly correlated with TCDD-EQs. TEFs based on single congener mammalian studies yielded TEQs that greatly exceeded values from the H411E bioassay of field sample. TEFs generated from avian egg injection studies yielded TEQs that most closely approximated bioassay-derived TCDD-EQs. Cytochrome P450 parameters were related to TEQs and TCDD-EQs; adjusted r2 often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data document the general predictive value of TEQs and TCDD-EQs for P450 induction in field collected samples, but also indicate the need for development of TEFs for the species and biological end point of concern.

Rattner, B.; Hatfield, J.; Melancon, M.; Custer, T.; Tillitt, D.

1995-01-01

307

Rapid toxicity testing based on mitochondrial respiratory activity  

SciTech Connect

The need exists for rapid and inexpensive methods to determine the health effects of environmental contaminants on biological systems. One of the current research approaches for assessing cytotoxicity is to monitor the respiratory activity of the mitochondrion, a sensitive, nonspecific subcellular target site. Detected changes in mitochondrial function after the addition of a test chemical could be correlated to toxic effects. Mitochondrial respiration can be characterized by three indices: state 3 and state 4 respiratory rates, and the respiratory control ratio (RCR). State 4, the idle or resting state, results when coupled mitochondrial respire in a medium containing inorganic phosphate and a Kreb's cycle substrate in the absence of a phosphate acceptor such as adenosine diphosphate (ADP). In the presence of ADP the respiration rate increases to a maximum (state 3), accompanied by phosphorylation of ADP to adenosine triphosphate (ATP). The ratio of state 3 to state 4, or RCR, indicates how tightly the oxidative phosphorylation process is coupled. The synthesis of ATP by mitochondria is influenced by a number of compounds, most of which are either uncouplers or inhibitors.

Haubenstricker, M.E. (Environmental Protection Agency, Ann Arbor, MI (USA)); Holodnick, S.E.; Mancy, K.H. (Univ. of Michigan, Ann Arbor (USA)); Brabec, M.J. (Eastern Michigan Univ., Ypsilanti (USA))

1990-05-01

308

Handling nonnormality and variance heterogeneity for quantitative sublethal toxicity tests.  

PubMed

The advantages of using regression-based techniques to derive endpoints from environmental toxicity data are clear, and slowly, this superior analytical technique is gaining acceptance. As use of regression-based analysis becomes more widespread, some of the associated nuances and potential problems come into sharper focus. Looking at data sets that cover a broad spectrum of standard test species, we noticed that some model fits to data failed to meet two key assumptions-variance homogeneity and normality-that are necessary for correct statistical analysis via regression-based techniques. Failure to meet these assumptions often is caused by reduced variance at the concentrations showing severe adverse effects. Although commonly used with linear regression analysis, transformation of the response variable only is not appropriate when fitting data using nonlinear regression techniques. Through analysis of sample data sets, including Lemna minor, Eisenia andrei (terrestrial earthworm), and algae, we show that both the so-called Box-Cox transformation and use of the Poisson distribution can help to correct variance heterogeneity and nonnormality and so allow nonlinear regression analysis to be implemented. Both the Box-Cox transformation and the Poisson distribution can be readily implemented into existing protocols for statistical analysis. By correcting for nonnormality and variance heterogeneity, these two statistical tools can be used to encourage the transition to regression-based analysis and the depreciation of less-desirable and less-flexible analytical techniques, such as linear interpolation. PMID:19364187

Ritz, Christian; Van der Vliet, Leana

2009-09-01

309

40 CFR 797.1600 - Fish early life stage toxicity test.  

Code of Federal Regulations, 2012 CFR

...description of the brood stock history or embryo source shall be made...the dilution water (fresh or salt) shall be between 90 percent...testing. (2 ) Artificial sea salts may be added to natural seawater...and how verified and source history, observed diseases,...

2012-07-01

310

40 CFR 797.1600 - Fish early life stage toxicity test.  

Code of Federal Regulations, 2011 CFR

...description of the brood stock history or embryo source shall be made...the dilution water (fresh or salt) shall be between 90 percent...testing. (2 ) Artificial sea salts may be added to natural seawater...and how verified and source history, observed diseases,...

2011-07-01

311

Assessing TNT Toxicity on Soils With Contrasting Characteristics Using Soil Invertebrate Toxicity Tests.  

National Technical Information Service (NTIS)

We investigated the toxicity of 2,4,6- trinitrotoluene (TNT) to earthworm (Eisenia fetida), potworm (Enchytraeus crypticus), and springtail (Folsomia candida) in five natural soils: Sassafras sandy loam (SSL), Teller sandy loam (TSL), Richfield clay loam ...

M. Simini R. T. Checkai R. G. Kuperman C. T. Phillips J. E. Kolakowski

2004-01-01

312

COMPARATIVE TOXICITY TESTING OF SELECTED BENTHIC AND EPIBENTHIC ORGANISMS FOR THE DEVELOPMENT OF SEDIMENT QUALITY TEST PROTOCOLS  

EPA Science Inventory

Sediment contamination has resulted in the need to develop an appropriate suite of toxicity tests to assess ecotoxicological impacts on estuarine ecosystems. Existing Environmental Protection Agency (EPA) protocols recommend a number of test organisms, including amphipods, polych...

313

Aquatic toxicity tests for the control of effluent discharges in the UK - the influence of test precision.  

PubMed

: The initiative by the River Purification Boards (RPBs), National Rivers Authority (NRA) and Her Majesty's Inspectorate of Pollution (HMIP) to control certain complex and toxic effluent discharges by direct toxicity assessment places great emphasis on the use of aquatic toxicity tests. Like all biological and analytical measurements, determinations of toxicity exhibit variability. When setting 'Toxicity-based Consents' (TBCs) and monitoring for compliance with such consents, it is important to understand and if possible control this variability. The implications of toxicity test variability for the way TBCs may be set and monitored are discussed; including a consideration of monitoring consents based on a single exposure concentration (limit) test and procedures involving a range of exposure concentrations (concentration-response test). We also review the precision of data arising from acute aquatic toxicity test methods which may be used for the control and monitoring of complex effluents in the UK. This includes the variability that occurs when repeated tests are carried out on different occasions within the same laboratory (repeatability) and also within different laboratories (reproducibility). Particular attention is given to acute tests using Daphnia magna, the only method for which there is a large amount of published information on the precision of toxicity data. PMID:24193722

Whitehouse, P; Crane, M; John Redshaw, C; Turner, C

1996-06-01

314

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

SciTech Connect

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

Simbeck, D.J.

1997-06-01

315

Pyrrolizidine Alkaloids: Testing for Toxic Constituents of Comfrey.  

ERIC Educational Resources Information Center

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

Vollmer, John J.; And Others

1987-01-01

316

Toxicity Testing of Fat Emulsions for Intravenous Administration.  

National Technical Information Service (NTIS)

Clinical and histopathologic toxicity studies were conducted on fourteen fat emulsions including Lipomul, Intralipid, Lipofundin and cottonseed or soybean oil emulsions prepared commercially or experimentally for intravenous use. These emulsions were admi...

L. D. Jones M. W. Castleberry J. E. Canham N. W. King

1965-01-01

317

USER'S GUIDE FOR CONDUCTING LIFE-CYCLE CHRONIC TOXICITY TESTS WITH FATHEAD MINNOWS (PIMEPHALES PROMELAS)  

EPA Science Inventory

This paper represents the latest 'state-of-the-art' procedural guide for conducting life-cycle chronic toxicity tests with fathead minnow (Pimephales promelas). These new procedures are based on recent evaluations of published toxicity tests and methods used by aquatic toxicologi...

318

A theoretical model for simulating the outcome of mechanism based in vitro toxicity testing strategies  

Microsoft Academic Search

In order to investigate the fundamental principles that influence the optimal selection of toxicity test methods for the evaluation of chemical hazards, it is useful to have a design model to explore possible alternative testing strategies. In general, our lack of detailed knowledge of the mechanisms of toxicity (including not only the early events in the interaction of chemicals with

John M Frazier

2004-01-01

319

40 CFR 797.1600 - Fish early life stage toxicity test.  

Code of Federal Regulations, 2010 CFR

...followed by random assignment of a second group of equal number to each...analysis of data derived from early life stage toxicity tests; however...versus each concentration. A second technique is to identify treatment...criteria. (A) An early life stage toxicity test is...

2009-07-01

320

40 CFR 797.1600 - Fish early life stage toxicity test.  

Code of Federal Regulations, 2010 CFR

...followed by random assignment of a second group of equal number to each...analysis of data derived from early life stage toxicity tests; however...versus each concentration. A second technique is to identify treatment...criteria. (A) An early life stage toxicity test is...

2010-07-01

321

Toxicity of smoke during chair smoldering tests and small scale tests using the same materials.  

PubMed

Toxicological evaluation of smoke produced during smoldering chair tests was undertaken by exposing mice to smoke emitted prior to, as well as following, flaming ignition of the chairs. By exposing several groups of mice, using undiluted smoke from the room containing the chairs, as well as various dilutions of the smoke, different levels of acute lethality were obtained. From these experiments, chairs constructed with polyurethane foam were found to create higher toxic atmospheres than chairs constructed with polyester or cotton fiber cushions. The same materials (polyurethane foam, polyester and cotton fibers) were also thermally decomposed in a small scale system and mice were exposed to the smoke to evaluate acute toxicity. Again polyurethane foam was found to produce smoke more toxic than smoke produced by polyester and cotton fibers. Sensory irritation monitored in mice during the smoldering tests indicated that an intense level of irritation was present long before large amounts of smoke were generated and long before flaming ignition occurred. The phenomenon of eye, nose and throat irritation would therefore be the first effect impeding escape attempts of individuals in a fire situation. Sensory irritation was followed by asphyxiation as evolution of carbon monoxide or hydrogen cyanide, or both, occurred. The same pattern of responses was observed with smoke generated with the small scale decomposition system. PMID:6662303

Alarie, Y; Stock, M F; Matijak-Schaper, M; Birky, M M

1983-01-01

322

Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part III. Effluent Toxicity Tests  

EPA Science Inventory

This paper reports on the results of chronic toxicity tests conducted with common surrogate species, and several threatened and endangered species for which there were excess artificially propagated stock to allow direct testing....

323

ADVANTAGES OF USING REGRESSION ANALYSIS TO CALCULATE RESULTS OF CHRONIC TOXICITY TESTS  

EPA Science Inventory

Although it is traditional to calculate results of chronic toxicity tests using hypothesis testing to detect statistically significant differences from the control, calculation of results using regression analysis offers several major advantages. Regression analysis can directly ...

324

AN EVALUATION OF THE 7-DAY TOXICITY TEST WITH AMERICAMYSIS BAHIA (FORMERLY MYSIDOPSIS BAHIA)  

EPA Science Inventory

The 7-d test measuring survival, growth, and fecundity of Americamysis bahia formerly Mysidopsis bahia) was developed for estimating the chronic toxicity of effluents and associated receiving waters for National Pollutant Discharge Elimination System permits. Currently, this test...

325

ASSESSING CONTAMINANT SENSITIVITY OF ENDANGERED AND THREATENED SPECIES: EFFLUENT TOXICITY TESTS  

EPA Science Inventory

Toxicity tests using standard effluent test procedures were conducted (EPA 1994) with Ceriodaphnia dubia and fathead minnows and four endangered fish species: bonytail chub (Gila elegans), Colorado squawfish (Ptychocheilus lucias ), razorback sucker (Xyrauchen texanus) and Gila t...

326

Comparison and Evaluation of Field and Laboratory Toxicity Tests with Fenvalerate on an Estuarine Crustacean.  

National Technical Information Service (NTIS)

Field and laboratory toxicity tests were conducted on the grass shrimp, Palaemonetes pugio, to evaluate the usefulness of laboratory testing in estimating mortality from fenvalerate exposure associated with agricultural runoff. The study examined an integ...

D. S. Baughman D. W. Moore G. I. Scott

1989-01-01

327

Toxicity of PAHs and jelly protection of eggs in the Common frog Rana temporaria  

Microsoft Academic Search

Polycyclic Aromatic Hydrocarbons (PAHs) are damaging for aquatic organisms such as amphibians. In this study, toxicity of a mixture of three PAHs (naphthalene (2 rings), phenanthrene (3 rings) and pyrene (4 rings)) was tested on Common frog (Rana temporaria) embryos. The protective role of the jelly coat surrounding the eggs was studied by exposing embryos with and without jelly coat

Olivier Marquis; Annie Millery; Sylvie Guittonneau; Claude Miaud

2006-01-01

328

Documentation of toxicity testing results on increased supernate treatment rate of 2700 gallons/batch  

SciTech Connect

In February 1991, Reactor Materials increased the rate of supernate treatment in the M-Area Dilute Effluent Treatment Facility (DETF) from 1800 gallons to [approximately]2700 gallons of supernate per 36,000 gallon dilute wastewater batch. The first release of the treated effluent began on March 3, 1991. A series of whole effluent toxicity tests was conducted on the DETF effluent to determine if the increased supernate concentration would result in any chronic toxicity affects in the receiving stream (Tims Branch). The toxicity tests were conducted at instream concentrations equivalent to DETF release rates of 5, 10, 15, 20, and 25 gallons/min. The test results, based on 7-day Ceriodaphnia dubia chronic toxicity, indicated no toxicity effects at any concentration tested. Supernate treatment in DETF continued at the higher concentration.

Pickett, J.B.

1992-07-06

329

Triazole-induced gene expression changes in the zebrafish embryo.  

PubMed

The zebrafish embryo is considered to provide a promising alternative test model for developmental toxicity testing. Most systems use morphological assessment of the embryos, however, microarray analyses may increase sensitivity and predictability of the test by detecting more subtle and detailed responses. In this study, we investigated the possibility of relating gene expression profiles of structurally similar chemicals tested in a single concentration, to a complete transcriptomic concentration-response of flusilazole (FLU). We tested five other triazoles, hexaconazole (HEX), cyproconazole (CYP), triadimefon (TDF), myclobutanil (MYC), and triticonazole (TTC) at equipotent concentrations based on morphological evaluation. Results showed that every compound had a different degree of regulation within their anti-fungal and developmental toxicity pathways, steroid biosynthesis and retinol metabolism, respectively. Assuming that the ratio between these pathways is relevant for efficacy compared to developmental toxicity, we found TTC was more efficient and CYP was more toxic compared to the other triazoles. With the approach used in this study we demonstrated that gene expression data allow more comprehensive assessment of compound effects by discriminating relative potencies using these specific gene sets. The zebrafish embryo model can therefore be considered a useful vertebrate model providing information of relevant pathways related to anti-fungal mechanism of action and toxicological activity. PMID:22664267

Hermsen, Sanne A B; Pronk, Tessa E; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Piersma, Aldert H

2012-09-01

330

Toxicity Testing in the 21st Century: Defining New Risk Assessment Approaches Based on Perturbation of Intracellular Toxicity Pathways  

PubMed Central

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 21st 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.

Bhattacharya, Sudin; Zhang, Qiang; Carmichael, Paul L.; Boekelheide, Kim; Andersen, Melvin E.

2011-01-01

331

Human Sperm Bioassay for Reprotoxicity Testing in Embryo Culture Media: Some Practical Considerations in Reducing the Assay Time  

PubMed Central

Human sperm assay (HSA) is a preferred in house quality control and proficiency test (PT) practiced in fertility laboratories. HSA is performed over varying durations, apparently without following set criteria. To better understand the assay time required for reprotoxicity testing in embryo culture media, we compared American-Association-of-Bioanalysts-(AAB-) administered HSA data to our own assay performed using PT samples obtained from AAB. Participating laboratories were required to culture sperm for 48 hours to determine media acceptability. Conclusions drawn from 48- and 24-hour observations were the same, suggesting that HSA could identify reprotoxic media in less time than required by AAB. Our assay revealed that changes in motility grade in adulterated media are significantly different from those in control media. Furthermore, grade changes can be identified earlier than differences in motility loss between samples. Analyzing motility and motility quality together provides a method for establishing an optimal time for HSA.

Hossain, Amjad; Aryal, Subhash; Osuampke, Collin; Phelps, John

2010-01-01

332

Tests with Daphnia magna: a new approach to prescreen toxicity of newly synthesized acetylcholinesterase reactivators.  

PubMed

Reactivators of phosphorylated acetylcholinesterase (oximes) are substances used as a human antidotal therapy for organophosphate poisoning. The objective of our study was to examine if juveniles of freshwater microcrustacean Daphnia magna could be employed as test animals in early screen toxicity tests of those substances as a first step for further experiments with daphnids intoxicated by organophosphates. For this purpose, seven different oximes were investigated. It was found that toxicity of all tested oximes increased with time. Mono-quaternary oximes were approximately ten fold (EC50, 14.9 mg.l(-1)) more toxic in 24 hour tests and five fold (EC50 was 79.46 mg.l(-1)) more toxic in 48 hour tests than bis-quaternary oximes. Tests with daphnids were shown to be easy to carry out at low cost and provided valuable results which could be used as a starting point for further research. PMID:17059176

Vesela, Sarka; Ondruska, Vlastimil; Kuca, Kamil; Patocka, Jiri

2006-08-01

333

THE ROLE OF IONORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING  

EPA Science Inventory

This paper assessess the issue of ion imbalance, provides summary of applicable data, presents several successful technical tools to address toxicity resulting from salinity and ion imbalances, and discusses regulatory/compliance options to manage discharges with salinity/ion imb...

334

ExpoCast: Exposure Science for Prioritization and Toxicity Testing  

EPA Science Inventory

The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize l...

335

Testing intravitreal toxicity of rapamycin in rabbit eyes  

Microsoft Academic Search

Purpose: To evaluate retinal toxicity of varying doses of rapamycin when injected intravitreally in rabbits. Rapamycin is a potent immunosup- pressive agent with significant antitumor and antiangiogenic properties, clinically approved for prevention of organ transplant rejection. Methods: Twelve New Zealand albino rabbits were divided into four groups. Four different doses of rapamycin were prepared in 0.1 ml: 20 ?g, 50

Roberta Pereira de Almeida Manzano; Gholam A. Peyman; Palwasha Khan; Muhamet Kivilcim; Patricia Chevez-Barrios; Walter Takahashi

2009-01-01

336

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

SciTech Connect

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 that the life-cycle characteristics of this species were conducive to traditional acute and chronic aquatic toxicity test methods. Acute toxicity tests showed that when comparing LC50 values for C. dubia and D. ambigua, D. ambigua was less sensitive to some toxicants (sodium chloride, copper sulfate, and sodium lauryl sulfate) while more sensitive to others (chlorpyrifos). Results of chronic tests with copper sulfate and sodium chloride resulted in the same NOEC/LOEC values for both species. When exposed to unaltered SRS stream water, C. dubia demonstrated a `toxic` response for two of the three streams tested, while reproduction for D. ambigua was higher in all stream samples. Acute toxicity tests with sodium chloride in stream water, generally followed the sensitivity trend noted in tests conducted with regular laboratory water.

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

1997-09-01

337

Development and evaluation of multispecies test protocols for assessing chemical toxicity  

SciTech Connect

Toxicity testing is a well-recognized tool to assist in evaluating the hazards of chemicals to individual biological species. Multispecies toxicity tests, however, are now well developed. Three test systems were examined: the legume-Rhizobium symbiosis for N-fixation, soil microbial populations, and algal multispecies interactions. Test protocols were to be developed and tested using several different chemicals. Test protocols for the legume-Rhizobium and soil microorganisms systems were developed and are presented. The algal multispecies system will require more research, and thus no protocol was recommended at this time. Separate abstracts were prepared for each test system. (ACR)

Garten, C.T. Jr.; Suter, G.W. II; Blaylock, B.G. (eds.)

1985-06-01

338

An interlaboratory comparison of sediment elutriate preparation and toxicity test methods.  

PubMed

Elutriate bioassays are among numerous methods that exist for assessing the potential toxicity of sediments in aquatic systems. In this study, interlaboratory results were compared from 96-h Ceriodaphnia dubia and Pimephales promelas static-renewal acute toxicity tests conducted independently by two laboratories using elutriate samples prepared from the same sediment. The goal of the study was to determine if the results from the elutriate tests were comparable between two U.S. Environmental Protection Agency (USEPA) laboratories when different elutriate preparation procedures were employed by each lab. Complete agreement in site characterization was attained in 22 of the 25 samples for both bioassays amongst each lab. Of the 25 samples analyzed, 10 were found to be toxic to at least one of the species tested by either laboratory. The C. dubia elutriate tests conducted by the National Exposure Research Laboratory (NERL) indicated that 7 of the 25 sediment samples were toxic, while 8 sediment samples were characterized as such in testing conducted by USEPA Region 6 (Region 6). The P. promelas elutriate tests conducted by NERL determined 8 samples as toxic, while Region 6 tests displayed toxicity in 5 of the samples. McNemar's test of symmetry for C. dubia (S?=?0.33, p?=?0.5637) and P. promelas (S?=?3.0, p?=?0.0833) tests indicated no significant differences in designating a site toxic between NERL and Region 6 laboratories. Likewise, Cohen's kappa test revealed significant agreement between NERL and Region 6 C. dubia (K?=?0.7148, p?tests. The authors conclude that differences in interlaboratory elutriate preparation procedures have no bearing on the ability of either the C. dubia or P. promelas bioassay testing methods to detect toxicity while yielding similar results. PMID:22278676

Haring, Herman J; Smith, Mark E; Lazorchak, James M; Crocker, Philip A; Euresti, Abel; Blocksom, Karen; Wratschko, Melissa C; Schaub, Michael C

2012-12-01

339

The sensitivity of grass shrimp, Palaemonetes pugio, embryos to organophosphate pesticide induced acetylcholinesterase inhibition.  

PubMed

Grass shrimp, Palaemonetes pugio, are common inhabitants of salt marshes along the Atlantic and Gulf coasts of North America. Grass shrimp embryos are brooded externally on the abdomen of adult females for about 2 weeks prior to hatching. In South Carolina, the spring spawning period for grass shrimp coincides with the period of peak pesticide application on crops grown along the South Carolina coast. Thus, grass shrimp of all developmental stages are at risk of exposure to pesticides present in nonpoint source agricultural runoff. Organophosphate (OP) insecticides are commonly applied agricultural chemicals which produce toxicity by inhibiting the nervous system enzyme, acetylcholinesterase (AChE). The purpose of this study was to examine the development of AChE activity in grass shrimp embryos and to assess their sensitivity to OP-induced AChE inhibition. Embryos were exposed for 24 h to either chlorpyrifos or malathion. All exposure concentrations were nominal and ranged from 0 to 2.00 µg l(-1) for chlorpyrifos and from 0 to 120.00 µg l(-1) for malathion. Quantifiable levels of AChE activity first appeared at Stage V of development and increased as embryonic development progressed. AChE inhibition by the OPs was assessed in Stage VI and Stage VII embryos. Both stages of embryos were more sensitive to chlorpyrifos than malathion. The 24-h Effective Concentration (EC(50)) values for chlorpyrifos were 0.49 µg l(-1) (95% C.I.=0.33-0.77 µg l(-1)) and 0.36 µg l(-1) (95% C.I.=0.33-0.38 µg l(-1)) for Stage VI and Stage VII embryos, respectively. In comparison, malathion 24-h EC(50) values were 55.53 µg l(-1) (95% C.I.=22.08-80.73 µg l(-1)) for Stage VI embryos and 29.93 µg l(-1) (95% C.I.=25.22-44.22 µg l(-1)) for Stage VII embryos. For both OPs, there were no significant differences in the EC(50) values calculated for Stage VI and Stage VII embryos; however, AChE inhibition was significantly (Pembryos at the two highest exposure concentrations for each insecticide. A comparison of the results of these embryo tests with those found for adult and larval toxicity tests indicated that embryos were at least as sensitive to both the OPs as larval and adult grass shrimp. Embryo bioassays provide a number of important advantages over traditional laboratory toxicity tests including reduced laboratory space requirements, large numbers of embryos from a few ovigerous females, and small volumes of waste. PMID:10686320

Lund; Fulton; Key

2000-03-01

340

DEVELOPMENT OF PROTOCOLS FOR CHRONIC TOXICITY TESTING OF PACIFIC MARINE SPECIES  

EPA Science Inventory

Development of a year-round capability for conducting short-term toxicity tests for estimating chronic effect levels of toxic materials with a native Pacific coast fish and a native Pacific coast mysid shrimp was the goal of this project. n order to achieve acceptable sensitivity...

341

Toxicity Reduction Test to Assist in Predicting Land Treatability of Hazardous Organic Wastes.  

National Technical Information Service (NTIS)

Migration of toxic organics contained in the water soluble fraction (WSF) of land applied hazardous wastes poses the most serious threat to ground-water resources. A toxicity reduction (TR) test system is being proposed that will serve to determine if, an...

J. E. Matthews A. A. Bulich

1985-01-01

342

Reproductive toxicity testing of pharmaceutical compounds to support the inclusion of women in clinical trials  

Microsoft Academic Search

1 The potential for toxicity to reproduction and the developing fetus is an important concern requiring attention during the development of new medicines. However, there are differences in the opinions of the regulatory authorities in Europe, Japan and the USA regarding the nature and amount of data from reproductive toxicity tests that should be available at the various stages of

Chris Parkinson; Kate E Thomas; Cyndy E Lumley

1997-01-01

343

DEVELOPMENT OF A TOXICITY TEST SYSTEM USING PRIMARY RAT LIVER CELLS  

EPA Science Inventory

A model in vitro rat liver parenchymal cellular toxicity system employing cells obtained by the in situ collagenase perfusion technique has been developed to detect potential liver toxicants. The initial evaluation of this test system was accomplished using cadmium chloride, chro...

344

Computerized In Vitro Test for Chemical Toxicity Based on Tetrahymena Swimming Patterns  

NASA Technical Reports Server (NTRS)

An apparatus and a method for rapidly determining chemical toxicity have been evaluated as an alternative to the rabbit eye initancy test (Draize). The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The method, called the motility assay (MA), is tested for 30 s to determine the chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy.

Noever, David A.; Matsos, Helen C.; Cronise, Raymond J.; Looger, Loren L.; Relwani, Rachna A.; Johnson, Jacqueline U.

1994-01-01

345

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

EPA Science Inventory

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

346

Design of vitrification solutions for the cryopreservation of embryos.  

PubMed

A series of experiments was performed to determine the concentrations at which ten cryoprotectants singly and in pairs would vitrify on plunging into liquid nitrogen and remain vitreous when warmed by plunging into a water bath at 25 degrees C. From these tests eight solutions (VS) were selected for testing of toxicity to mouse morulae in vitro. One of these (VS1) was modified as a further five VS of which one (VS11) was tested for toxicity to all stages of mouse embryos and to sheep compacted morulae. The concentrations at which the cryoprotectants vitrified on cooling were: butylene glycol, 3.0 mol l-1; propylene glycol, 4.0 mol l-1; dimethyl sulfoxide (DMSO) and glycerol 5.0 mol l-1; ethylene glycol, 6.5 mol l-1. None of these, at the highest concentration tested, remained vitreous during warming. Methanol and the high molecular weight polymers, dextran, Ficoll, polyethylene glycol and polyvinylpyrrolidone, did not vitrify at the concentrations tested. Toxicity studies showed the order of increasing toxicity to be ethylene glycol, methanol, DMSO, glycerol, propylene glycol and butylene glycol. Of the mixtures composed of two cryoprotectants, those containing ethylene glycol and glycerol were the least toxic at vitrifying concentrations. VS11 (6.0 mol ethylene glycol l-1 and 1.8 mol glycerol l-1) was well tolerated by mouse morulae, less well by eight- and one-cell embryos and poorly by two-cell embryos. Dilution of the VS11 from mouse embryos by exposure to 1.0 mol sucrose l-1 for 10 min did not enhance their survival.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8107029

Ali, J; Shelton, J N

1993-11-01

347

Concentration-time data in toxicity tests and resulting relationships  

NASA Technical Reports Server (NTRS)

Periodic analyses for carbon monoxide and methane in the animal exposure chamber during pyrolysis of polyethylene at 800 C without forced air flow showed that the concentrations of these compounds increased with exposure time. These observations, and similar observations for polyurethane flexible foam, permitted the calculation of carbon monoxide toxicity in terms of a DP (Death Product Concentration) value, in addition to flammability in terms of HC (Hydro Carbon) value. Observed DP values exceeding the critical DP(CO) value of 47,200 ppm-min for carbon monoxide may indicate that lethal exposures were reached earlier but not immediately manifested because of the time delay involved in physiological processes. On the basis of this DP(CO) value, carbon monoxide could have been the sole toxicant in the case of polyethylene, polypropylene, polyoxymethylene, polystyrene, polycarbonate, ethylene propylene diene rubber, and wood.

Hilado, C. J.; Brauer, D. P.

1979-01-01

348

[Subchronic toxicity testing of mold-ripened cheese].  

PubMed

The biological effects of known mycotoxins of Penicillium roqueforti or P. camemberti and other still unknown, but potentially toxic metabolites in mould ripened cheese (commercial samples of Blue- and Camembert cheese) were investigated. High amounts of mycelium (equivalents of 100 kg cheese/man and day) were fed to mice in a subchronic feeding trial. The following parameters were determined: development of body weight, organ weights, hematology, blood plasma enzymes. No signs of adverse effects produced by cheese mycotoxins could be detected after 28 days. No still unknown toxic metabolites could be demonstrated. From these results no health hazard from the consumption of mould ripened cheese, even in high amounts, appears to exist. PMID:6485557

Schoch, U; Lüthy, J; Schlatter, C

1984-08-01

349

Effect of Calcium Chloride on the Permeation of the Cryoprotectant Dimethyl Sulfoxide to Japanese Whiting Sillago japonica Embryos  

NASA Astrophysics Data System (ADS)

Cryopreservation of fish eggs and embryos is a highly desired tool to promote aquaculture production and fisheries resource management, but it is still not technically feasible. The failure to develop successful cryopreservation protocols for fish embryos is largely attributed to poor cryoprotectant permeability. The purpose of this study was to test the effectiveness of CaCl2 to enhance cryoprotectant uptake by fish embryos. In this study, embryos (somites and tail elongation stages) of Japanese whiting Sillago japonica were exposed to 10 and 15% dimethyl sulfoxide (DMSO) in artificial sea water (ASW) or a solution of 0.125M CaCl2 in distilled water for 20 min at 24°C. The toxicity of all solutions was estimated from the hatching rates of the embryos and High Performance Liquid Chromatography was used to determine the amount of DMSO taken up during impregnation. The results showed that DMSO incorporation into the embryos was greatly (›50%) enhanced in the presence of CaCl2 compared to ASW. CaCl2 itself was not toxic to the embryos but, probably as a result of the enhanced DMSO uptake, caused decreases in survival of about 14-44% relative to ASW. Somites stage embryos were more tolerant than tail elongation ones to DMSO both as ASW and CaCl2 solutions. The use of CaCl2 as a vehicle for DMSO impregnation could be a promising aid for the successful cryopreservation of fish embryos.

Rahman, Sk. Mustafizur; Majhi, Sullip Kumar; Suzuki, Toru; Strussmann, Carlos Augusto; Watanabe, Manabu

350

Validity of Computerized Testing in Toxic Encephalopathy, Final Performance Report.  

National Technical Information Service (NTIS)

The computer-assisted Neurobehavioral Evaluation System (NES) test battery was developed for the purpose of detecting brain dysfunction resulting from exposure to neurotoxicants. The NES tests are derived from standard neuropsychological tests that have b...

1999-01-01

351

Environmental impact assessment of tailings dispersal from a uranium mine using toxicity testing protocols  

SciTech Connect

Toxicity testing is a means of establishing the environmental risk of uranium tailings release. It is valuable in designing tailings containment structures because it assists in setting acceptable levels of risk of the design. This paper presents details of toxicity tests of the tailings from Ranger Uranium Mine, Northern Territory, Australia. The results suggest that the non-radiological toxicity of the tailings is low. The environmental risk of a tailings release is more likely to be related to the physical impacts of the tailings, including infilling of billabongs and changes in the sedimentology of riparian ecosystems rather than their biogeochemical impact. Two major results were: (1) water from treatment with washed tailing fines was not toxic to Hydra viridissima, and (2) mixtures of washed tailings fines and natural floodplain sediment (overlying water or elutriates) were not toxic to Hydra viridissima or Moinodaphnia macleayi. 33 refs., 4 figs., 3 tabs.

Rippon, G.D. [Environmental Protection Agency, Canberra (Australia); Riley, S.J. [Univ. of Western Sydney-Nepean, Kingswood (Australia)

1996-12-01

352

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

USGS Publications Warehouse

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

Hooten, R. L.; Carr, R. S.

1998-01-01

353

A Roadmap for the Development of Alternative (Non-Animal) Methods for Systemic Toxicity Testing  

EPA Science Inventory

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 prod...

354

What Food and Feeding Rates are Optimum for the Chironomus dilutus Sediment Toxicity Test Method?  

EPA Science Inventory

Laboratory tests with benthic macroinvertebrates are commonly used to assess the toxicity of both contaminated sediments and individual chemicals. Among the standard procedures for benthic macroinvertebrates are 10-d, 20-d, and life cycle exposures using the midge, Chironomus ...

355

DEVELOPMENT OF EPA'S TOXCAST PROGRAM FOR PRIORITIZING THE TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS.  

EPA Science Inventory

EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS)and genomic technologies to predict potential toxicity and prioritize the use of limited testing resources....

356

USE OF MARSH PLANTS FOR TOXICITY TESTING OF WATER AND SEDIMENT  

EPA Science Inventory

The freshwater wetland plants, Echinochlo crusgalli crusgalli andEchinocloa crusgalli zelayensis, and the saltmarsh plant, Spartina alterniflora, were exposed to the herbicides, metolachlor and norflurazon, in two types of toxicity tests: eed germination and early seedling growth...

357

TOXICITY TESTS OF EFFLUENTS WITH MARSH PLANTS IN WATER AND SEDIMENT  

EPA Science Inventory

Methods are described for toxicity testing of water and sediment with the rooted marsh plants, Echinochloa crusgalli var. crusgalli and var. zelavensis (freshwater) and Spartina alterniflora (estuarine). ive industrial effluents, a sewage treatment plant effluent and a herbicide ...

358

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

EPA Science Inventory

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

359

Design and Testing of Non-Toxic RCS Thrusters for Second Generation Reusable Launch Vehicle.  

National Technical Information Service (NTIS)

Under NASA sponsorship, Northrop Grumman Space Technology (NGST) designed, built and tested two non-toxic, reaction control engines, one using liquid oxygen (LOX) and liquid hydrogen (LH2) and the other using liquid oxygen and ethanol. This paper presents...

J. Calvignac L. Dang T. L. Tramel L. Paseur

2003-01-01

360

EPAS TOXCAST PROGRAM FOR PREDICTING HAZARD AND PRIORITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS(S).  

EPA Science Inventory

EPAs National Center for Computational Toxicology is developing methods that apply computational chemistry, high-throughput screening (HTS) and genomic technologies to predict potential toxicity and prioritize the use of limited testing resources....

361

Intra- and interlaboratory variability in acute toxicity tests with glochidia and juveniles of freshwater mussels (Unionidae)  

USGS Publications Warehouse

The present study evaluated the performance and variability in acute toxicity tests with glochidia and newly transformed juvenile mussels using the standard methods outlined in American Society for Testing and Materials (ASTM). Multiple 48-h toxicity tests with glochidia and 96-h tests with juvenile mussels were conducted within a single laboratory and among five laboratories. All tests met the test acceptability requirements (e.g., ???90% control survival). Intralaboratory tests were conducted over two consecutive mussel-spawning seasons with mucket (Actinonaias ligamentina) or fatmucket (Lampsilis siliquoidea) using copper, ammonia, or chlorine as a toxicant. For the glochidia of both species, the variability of intralaboratory median effective concentrations (EC50s) for the three toxicants, expressed as the coefficient of variation (CV), ranged from 14 to 27% in 24-h exposures and from 13 to 36% in 48-h exposures. The intralaboratory CV of copper EC50s for juvenile fatmucket was 24% in 48-h exposures and 13% in 96-h exposures. Interlaboratory tests were conducted with fatmucket glochidia and juveniles by five laboratories using copper as a toxicant. The interlaboratory CV of copper EC50s for glochidia was 13% in 24-h exposures and 24% in 48-h exposures, and the interlaboratory CV for juveniles was 22% in 48-h exposures and 42% in 96-h exposures. The high completion success and the overall low variability in test results indicate that the test methods have acceptable precision and can be performed routinely. ?? 2007 SETAC.

Wang, N.; Augspurger, T.; Barnhart, M. C.; Bidwell, J. R.; Cope, W. G.; Dwyer, F. J.; Geis, S.; Greer, I. E.; Ingersoll, C. G.; Kane, C. M.; May, T. W.; Neves, R. J.; Newton, T. J.; Roberts, A. D.; Whites, D. W.

2007-01-01

362

Toxicity evaluation with Vibrio fischeri test of organic chemicals used in aquaculture.  

PubMed

The evaluation of acute toxicity by Vibrio fischeri test for different organic chemicals (antibiotics, pesticides, therapeutants, herbicides) commonly applied in aquaculture and a degradation product of surfactants, 4-nonylphenol, is presented in this work. Simazine, atrazine, emamectin benzoate and leucomalachite green have no toxic effects on V. fischeri at the concentration tested (up to 6mgl(-1)) which correspond to the maximum water solubility. Ciprofloxacin, terbutryn and deltamethrin, caused inhibition effects of 28%, 22% and 30% at concentrations up to 5mgl(-1). Toxic effects were not observed in the case of flumequine and oxolinic acid at the maximum concentration tested (0.189mgl(-1)). According to the toxicity categories established in the EU legislation, ciprofloxacin, terbutryn and deltamethrin could be considered non-harmful for V. fischeri. Malachite green and 4-nonylphenol are "very toxic to aquatic organisms" (EC(50,30min)=0.031mgl(-1) and 0.48mgl(-1), respectively). Carbaryl is "toxic to aquatic organisms" (2.4mgl(-1)). and glyphosate is harmful to V. fischeri (EC(50,30min)=44.2mgl(-1)). The matrix effect was evaluated comparing the toxicity measurements of the target compounds solubilized in seawater and distilled water. Malachite green, 4-nonylphenol and glyphosate, showed higher toxicity in distilled water than in seawater. Carbaryl was more toxic in seawater. All the compounds tested in seawater were not harmful at concentrations of ngl(-1) (10 and 50). However, 4-nonlylphenol and malachite green may act as toxic compounds in the environment at a low ppb level, since both may be detected in water at this concentration level. PMID:17292447

Hernando, M D; De Vettori, S; Martínez Bueno, M J; Fernández-Alba, A R

2007-06-01

363

Shake-flask test for estimation of biodegradability of toxic organic substances in the aquatic environment  

SciTech Connect

Disadvantages of current biodegradation tests are examined: the need for high substrate concentrations, lack of parent compound concentration measurements, no estimation of sediment effects, failure to indicate compounds to which microbial populations must adapt to degrade, and lack of site specificity in innocula selection. A modified river die-away test is proposed for determining biodegradability of organic compounds and testing for toxic degradation products. The present test uses shake flasks containing sterile (2% formalin) and nonsterile site water: both with, and without, site sediment (500 mg/liter). Concurrent toxicity testing with mysids or daphnids provides a sensitive assay for the detection of toxic metabolites. Examples of three test compounds are given: methyl parathion, which undergoes rapid, sediment-mediated biodegradation; dibutylphthalate, to which some microbial communities exhibit an adaptation phenomenon; and methoxychlor, which has a relatively low water solubility and high sediment partition coefficient. The relative merits of this test procedure are discussed.

Cripe, C.R.; Walker, W.W.; Pritchard, P.H.; Bourquin, A.W.

1987-12-01

364

Comparative studies on algal toxicity testing using fluorometric microplate and Erlenmeyer flask growth-inhibition assays  

Microsoft Academic Search

Two fluorometric microplate algae growth-inhibition assays with a liquid volume of 2mL and 200?L per well are presented, and comparative studies on the toxicity of chemicals are carried out with Erlenmeyer flask assays. The test procedures are in accordance with the standards ISO 8692 (DIN 38412 L9 and EN 28692), OECD 201 and DIN 38412 L33. By testing four toxicants

Adolf Eisentraeger; Wolfgang Dott; Joern Klein; Stefan Hahn

2003-01-01

365

Genotoxicity and toxicity evaluations of ECF cellulose bleaching effluents using the Allium cepa L. test.  

PubMed

Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate wastewater quality following an ECF cellulose bleaching process. The results revealed a toxic effect of the effluent, with inhibition of meristem growth and generally lower values of metaphase, anaphase and telophase indices at pH 10.5 than pH 7 for all effluent concentrations. The genotoxicity effect was different from the toxic effect given that the micronucleus and the chromosomal aberration tests in anaphase-telophase cells were low over all ranges of the studied effluent concentrations. PMID:22990817

Roa, O; Yeber, M C; Venegas, W

2012-08-01

366

Computerized in vitro test for chemical toxicity based on tetrahymena swimming patterns  

NASA Technical Reports Server (NTRS)

An apparatus and method for rapidly determining chemical toxicity was evaluated. The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The device, called the Motility Assay Apparatus (MAA) is tested for 30 second determination of chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy, in addition to agreeing for all chemicals with previous manual evaluations of single cell motility.

Noever, David A.; Matsos, Helen C.; Cronise, Raymond J.; Looger, Loren L.; Relwani, Rachna A.; Johnson, Jacqueline U.

1994-01-01

367

Toxicity tests of soil contaminated by recycling of scrap plastics  

SciTech Connect

The present investigation studied the toxicity of soil contaminated by untreated discharge from a factory that recycles used plastics. The nearby agricultural areas and freshwater fish ponds were polluted with high concentrations of Cu, Ni, and Mn. Water extracts from the contaminated soil retarded root growth of Brassica chinensis (Chinese white cabbage) and Cynodon dactylon (Bermuda grass) where their seeds were obtained commercially. The contaminated populations of C. dactylon, Panicum repen (panic grass), and Imperata cylindrica (wooly grass) were able to withstand higher concentrations of Cu, Ni, and Mn, especially C. dactylon, when compared with their uncontaminated counterparts.

Wong, M.H.; Chui, V.W. (Hong Kong Baptist College, Kowloon (Hong Kong))

1990-03-01

368

Hazard Evaluation Division, Standard Evaluation Procedure: Acute Toxicity Test for Estuarine and Marine Organisms (Estuarine Fish 96-Hour Acute Toxicity Test).  

National Technical Information Service (NTIS)

The Standard Evaluation Procedure (SEP) for the Estuarine Fish 96-Hour Acute Toxicity Test is a guidance document primarily intended for Agency reviewers and the regulated industry who evaluate ecological effects data specified in 40 CFR Part 158.145. The...

D. Rieder

1985-01-01

369

2,3,7,8-Tetrachlorodibenzo-p-dioxin Toxicity in the Zebrafish Embryo: Altered Regional Blood Flow and Impaired Lower Jaw Development  

Microsoft Academic Search

The effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) ex- posure on regional red blood cell (RBC) perfusion rate, as an index of blood flow, and lower jaw development were investigated quan- titatively in zebrafish embryos (Danio rerio) during early develop- ment. As revealed by observation of live embryos and alcian-blue staining, TCDD retarded lower jaw development in a concentra- tion-dependent manner with only

Hiroki Teraoka; Wu Dong; Shuji Ogawa; Shusaku Tsukiyama; Yuji Okuhara; Masayoshi Niiyama; Naoto Ueno; Richard E. Peterson; Takeo Hiraga

2002-01-01

370

Toxic actions of dinoseb in medaka ( Oryzias latipes) embryos as determined by in vivo 31P NMR, HPLC-UV and 1H NMR metabolomics  

Microsoft Academic Search

Changes in metabolism of Japanese medaka (Oryzias latipes) embryos exposed to dinoseb (2-sec-butyl-4,6-dinitrophenol), a substituted dinitrophenol herbicide, were determined by in vivo 31P NMR, high-pressure liquid chromatography (HPLC)-UV, and 1H NMR metabolomics. ATP and phosphocreatine (PCr) metabolism were characterized within intact embryos by in vivo 31P NMR; concentrations of ATP, GTP, ADP, GDP, AMP and PCr were determined by HPLC-UV;

Mark R. Viant; Christopher A. Pincetich; David E. Hinton; Ronald S. Tjeerdema

2006-01-01

371

Influence of sediment composition on apparent toxicity in a solid-phase test using bioluminescent bacteria  

SciTech Connect

Clean and spiked sediment formulations of various silt:sand and clay:sand ratios were tested for toxicity using a bioassay that utilizes bioluminescent bacteria. Measured toxicities of clean and copper sulfate-spiked sediments were negatively but nonlinearly related with percent silt and percent clay, but no significant relationship existed between measured toxicity and sediment composition for methyl parathion-spiked formulations. Results suggest that solid-phase sediment bioassays using bioluminescence bacteria may be useful for testing the toxicities of single contaminants in formulated artificial sediments of known particle-size composition, and for repeated samples collected from the same site. However, extreme caution must be taken when testing sediments of varying composition or which may be differentially contaminated or contain a suite of contaminants.

Benton, M.J. [East Tennessee State Univ., Johnson City, TN (United States). Dept. of Environmental Health; Malott, M.L. [Univ. of Mississippi, University, MS (United States)]|[Dept. of Agriculture, Oxford, MS (United States); Knight, S.S.; Cooper, C.M. [Dept. of Agriculture, Oxford, MS (United States); Benson, W.H. [Univ. of Mississippi, University, MS (United States)

1995-03-01

372

Cumulative bioluminescence; A potential rapid test of drilling fluid toxicity: development study  

SciTech Connect

A new rapid test of drilling fluid toxicity is based on the spontaneous bioluminescence of Pyrocystis lunula, an easy-to-culture alga that vigorously responds to shear stress (mixing) by emitting a sharp burst of light. In contrast to other bioluminescence methods, a cumulative flux of light is measured with a photomultiplier that eliminates the effect of exposure time on test results. Light quenching, caused by the presence of a toxicant, results in the dose/response relationship (DSR) typical for the enzymatic reaction kinetics. The Michaelis-Menten (dissociation) constant is used as a direct measure of toxicity. The evaluation study involved multiple experiments with 60 samples of drilling fluids from the U.S. gulf coast, as well as such typical toxicants as diesel oil, mineral oil, and chrome lignosulfonate (CLS). In this paper, the results of the test error analysis and comparisons with the Microtox and Mysid shrimp assays are reported.

Stiffey, A.V. (Naval Oceanographic and Atmospheric Research Lab. (US))

1992-03-01

373

Cross-sector review of drivers and available 3Rs approaches for acute systemic toxicity testing.  

PubMed

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area. PMID:20484382

Seidle, Troy; Robinson, Sally; Holmes, Tom; Creton, Stuart; Prieto, Pilar; Scheel, Julia; Chlebus, Magda

2010-08-01

374

Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing  

PubMed Central

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area.

Seidle, Troy; Robinson, Sally; Holmes, Tom; Creton, Stuart; Prieto, Pilar; Scheel, Julia; Chlebus, Magda

2010-01-01

375

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...or other particulates into the solutions. (ii) Cleaning. Test...and equipment that contact test solutions should be chosen to minimize...substances that can be leached into aqueous solution in quantities that can...

2009-07-01

376

Use of a general toxicity test to predict heavy metal concentrations in residential soils.  

PubMed

Significant clusters of developmental delay and mental retardation (DD/MR) were identified in children born in South Carolina. Although it is difficult to identify one factor that causes DD/MR, environmental insult including exposure of pregnant women to heavy metals can induce DD/MR in their children. Because it is expensive to measure the concentrations of individual metals in large numbers of environmental samples, the general Microtox toxicity test was used to identify highly toxic soil samples. Approximately 100 soil samples were collected from residential areas and analyzed to determine an effective concentration (EC(50)) of soil required to inhibit 50% light emission of the luminescent bacterial test organism (Vibrio fischeri). The EC(50) values were then transformed to relative toxicity units (RTU). A subset of 56 high and low toxicity soil samples was then analyzed by inductively coupled plasma-atomic emission spectrometry (EPA method 6010) for arsenic, lead, and chromium, which are known neurotoxins. The highest measured arsenic concentration was 30 times higher than the South Carolina residential soil limit. Significant correlations were found between the RTU and soil arsenic and chromium concentrations. Microtox also identified some low arsenic and chromium samples as toxic, presumably because additional unidentified toxicants were present in the soil. In general, however, the Microtox test was effective in identifying soils with elevated concentrations of arsenic and chromium, even in residential neighborhoods where limited soil toxicity was expected. PMID:17140621

Aelion, C Marjorie; Davis, Harley T

2007-03-01

377

Synergistic Effects of Copper and Butylic Ester of 2,4-Dichlorophenoxyacetic Acid (Esternon Ultra) on Amphibian Embryos  

Microsoft Academic Search

Cu 2+ and butylic ester of 2,4-Dichlorophenoxyacetic acid as Esternon Ultra (2,4-D) toxicity on Bufo arenarum embryos were evaluated by means of a short -term chronic toxicity test (AMPHITOX). The NOEC values for Cu and 2,4-D were 0.02 mg\\/L and 2 mg\\/L respectively. The toxicity profile curves for Cu and 2,4-D were reported. The interactions of the metal and the

Cristina Silvia Pérez-Coll; Jorge Herkovits

2006-01-01

378

Relative toxicity testing of spacecraft materials. 2: Aircraft materials  

NASA Technical Reports Server (NTRS)

The relative toxicity of thermodegradation (pyrolysis/combustion) products of aircraft materials was studied. Two approaches were taken to assess the biological activity of the pyrolysis/combustion products of these materials: (1) determine the acute lethality to rats from inhalation of these pyrolysates and (2) examine the tendency for sublethal exposure to the pyrolysates to disrupt behavioral (shock avoidance) performance of exposed rats. The ralative importance of lethality vs. behavioral effects in selection of a material may be dictated by whether or not individuals potentially exposed to such products, would have an opportunity to escape if they were behaviorally capable of doing so. If so, the second parameter would assume greater importance, but if not the first parameter may be of much greater importance in selecting materials.

Lawrence, W. H.

1980-01-01

379

Acute toxicity testing with the tropical marine copepod Acartia sinjiensis: optimisation and application.  

PubMed

Globally there is limited toxicity data for tropical marine species, and there has been a call for further research and development in the area of tropical marine ecotoxicology. An increase in developmental pressures in northern tropical Australia is causing a higher demand for toxicity test protocols with ecologically relevant species. Copepods are a diverse group of zooplankton that are major components of marine food webs. The calanoid copepod Acartia sinjiensis is widely distributed across tropical and sub-tropical brackish to marine waters of Australia and was identified in a recent comprehensive review of marine tropical toxicity testing in Australia as a suitable test organism. Through a number of optimisation steps including feeding trials, changes to culture and test conditions; a 48-h acute toxicity test with A. sinjiensis was modified to become a highly reliable and reproducible standard test protocol. Control mobility was improved significantly, and the sensitivity of A. sinjiensis to copper (EC50 of 33µg/L), ammonia (EC50 of 10mg/L) and phenol (EC50 of 13mg/L) fell within the ranges of those reported previously, indicating that the modifications did not alter its sensitivity. In a comprehensive literature search we found that this species was the most sensitive to copper out of a range of marine copepods. The test was also successfully applied in toxicity assessments of four environmental samples: two produced formations waters (PFWs) and two mine tailing liquors (MTLs). The toxicity assessments utilised toxicity data from a suite of marine organisms (bacteria, microalgae, copepods, sea urchins, oysters, prawns, and fish). For the PFWs, which were predominantly contaminated with organic chemicals, A. sinjiensis was the most sensitive species (EC50 value 2-17 times lower than for any other test species). For the predominantly metal-contaminated mine tailing liquors, its sensitivity was similar to that of other test species used. The modified 48-h acute toxicity test with A. sinjiensis proved to be a valuable tool in these toxicity assessments, and is recommended for use in tropical marine toxicity assessments for northern Australia. PMID:23932510

Gissi, F; Binet, M T; Adams, M S

2013-11-01

380

Toxic Substances Control Act (TSCA) Test Submissions Database (TSCATS) - comprehensive update (on magnetic tape). Data file  

SciTech Connect

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data are submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test data are broadly defined to include case reports, episodic incidents, such as spills, and formal test study presentations. The database allows searching of test submissions 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.

NONE

1996-07-01

381

Individual and combined developmental toxicity assessment of bisphenol A and genistein using the embryonic stem cell test in vitro.  

PubMed

The potential developmental toxicity of environmental estrogenic endocrine disruptors have become a great concern in recent years. In this study, two typical environmental oestrogen, namely, bisphenol A (BPA) and genistein (GEN) were investigated for potential embryotoxicity using the embryonic stem cell test model. Afterwards, a 4×4 full factorial design and the estimated marginal means plot were performed to assess the combined effects of these two compounds. According to the linear discriminant functions and classification criteria, bisphenol A and genistein were classified as weakly embryotoxic and strongly embryotoxic respectively. As for combined effects, the overall interaction between BPA and GEN on embryonic stem cells (ESCs) differentiation was synergistic at low dosages, however, on ESCs and 3T3 cell proliferation, the predominate action was additive. Considering the actual daily intake of these chemicals, it is concluded that BPA alone might not have adverse reproductive or developmental effects on human being. However, given that BPA and GEN do have synergistic effect at low concentration, they may disturb normal embryo development together, which could result in birth defect and behavioral alterations later in life. PMID:23948354

Kong, Dan; Xing, Lina; Liu, Ran; Jiang, Jianjun; Wang, Wanyi; Shang, Lanqin; Wei, Xuetao; Hao, Weidong

2013-10-01

382

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2013 CFR

...used in the preparation of the nutrient medium. The pH of the test solution shall...autoclaving or filtration. The pH of the nutrient medium shall be 7.5 (±0...during testing. (iv) The pH of nutrient medium in which algae are...

2013-07-01

383

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...used in the preparation of the nutrient medium. The pH of the test solution shall...autoclaving or filtration. The pH of the nutrient medium shall be 7.5 (±0...during testing. (iv) The pH of nutrient medium in which algae are...

2010-07-01

384

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...used in the preparation of the nutrient medium. The pH of the test solution shall...autoclaving or filtration. The pH of the nutrient medium shall be 7.5 (±0...during testing. (iv) The pH of nutrient medium in which algae are...

2009-07-01

385

40 CFR 797.1330 - Daphnid chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...carapace in response to stress conditions in daphnids...intermittent passage of test solution or dilution water through...dilution water or test solution. (iv) Loading...ephippia and other signs of stress, physical damage...below the surface of any solution so as not to trap...

2009-07-01

386

Inhibition of embryo development of the commercial bivalves Ruditapes decussatus and Mytilus galloprovincialis by trace metals; implications for the implementation of seawater quality criteria  

Microsoft Academic Search

This study evaluates the risk posed by trace metals on the culture of bivalves in the Galician coast (NW Iberian Peninsula), which depends on collection of natural seed and larval rearing with natural seawater in hatcheries. With this aim, toxicity tests were carried out with embryos of the commercial bivalves Ruditapes decussatus and Mytilus galloprovincialis, and the toxicity of Hg,

R. Beiras; M. Albentosa

2004-01-01

387

Comparative Toxicity of Eight Oil Dispersants, Louisiana Sweet Crude Oil (LSC) and Chemically Dispersed LSC to Two Aquatic Test Species  

EPA Science Inventory

This study describes the acute toxicity of eight commercial oil dispersants, Louisiana sweet crude oil (LSC), and chemically dispersed LSC. The approach utilized consistent test methodologies within a single laboratory in assessing the relative acute toxicity of the eight dispers...

388

Toxicity of Pyrethroids to Marine Invertebrates and Fish: A Literature Review and Test Results with Sediment-Sorbed Chemicals.  

National Technical Information Service (NTIS)

Data on acute and chronic toxicity of permethrin, fenvalerate, cypermethrin, and flucythinate to marine invertebrates and fishes are reviewed. Laboratory toxicity tests were conducted with sediment-source fenvalerate and cypermethrin under static and flow...

J. R. Clark L. R. Goodman P. W. Borthwick J. M. Patrick G. M. Cripe

1989-01-01

389

Use of tracheal organ cultures in toxicity testing.  

PubMed Central

Fragments of tracheal epithelium alone or in continuity with connective tissues, can be maintained in culture medium and used for short term or long term studies of toxicity of a variety of chemicals. Large numbers of uniform cultures are prepared with the aid of a slicing device or by application of simple method for dissecting sheets of epithelium free from underlying cartilage. The cultures may be placed in an exposure chamber-incubator mounted on a microscope stage and monitored continually for ciliostasis and exfoliation of cells. Morphology is further studied by fixation of selected specimens and preparation for light microscopy and electron microscopy. Synthetic functions are evaluated by autoradiographic measurement of incorporation of radioactive precursors into macromolecules and other dynamic features are indirectly assessed by histochemical and histoenzymatic methods. Short-term studies using these several techniques have shown that ciliostasis does not correlate with cell injury in all instances, and a long-term study has demonstrated dose dependence of a cytotoxic agent when duration of culture viability is measured. The method lends itself to a broad range of investigations in which dose, period of exposure, and role of cofactors must be independently and quantitatively assessed. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. FIGURE 10. FIGURE 11. FIGURE 12.

Lane, B P; Miller, S L; Drummond, E J

1976-01-01

390

Toxic effects of occupational and environmental chemicals on the testes  

SciTech Connect

This paper examines evidence for effects of occupational chemicals on male reproduction. We consider primarily human data, and much of that from epidemiologic studies. We use animal studies to illustrate points, but the theme is the human experience. The approach is based on examining reproductive function as an indicator of toxic effects. Testicular structure and function is briefly discussed. We provide a brief review of relevant structure, function and hormonal control. We describe the anatomy of the testis and its histological structure. We then discuss the testis from the point of view of exocrine and endocrine function and the relationship of the testis to other endocrinological organs. This is followed by a review of methods for assessing human testicular function, including reproductive histories, sperm analysis, assessment of hormonal status, and histological studies. Although the primary focus is on human studies, we consider briefly general categories of chemicals shown to have a testicular effect in animal studies and also animal evidence of mechanisms of action associated with testicular toxicology. Specific chemicals shown to affect reproduction in the human male are reviewed and directions for future research in this area discussed.

Sever, L.E.; Hessol, N.A.

1983-01-01

391

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

Microsoft Academic Search

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®, silver, and CdSe\\/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable

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

2009-01-01

392

DIETARY TOXICITY TEST FOR 2% DRC1339TREATED BROWN RICE ON NONTARGET AVIAN SPECIES  

Microsoft Academic Search

In Louisiana and Texas DRC-1339-treated brown rice is used to manage blackbird populations that cause severe damage to newly planted rice. Nontarget bird species have been observed on some DRC-1339 bait sites. We conducted dietary toxicity tests to provide additional data on the toxicity of DRC-1339 to the following nontarget species observed on DRC-1339 bait sites: savannah sparrows (Passerculus sandwichensis),

JOHN L. CUMMINGS; DARRYL L. YORK; KIRK J. SHIVELY; PATRICIA A. PIPAS; RANDAL S. STAHL; JAMES E. DAVIS

393

Evaluation of the OECD 421 reproductive toxicity screening test protocol using butyl benzyl phthalate  

Microsoft Academic Search

The OECD421 reproductive toxicity screening test protocol was evaluated using the reproductive and developmental toxicant butyl benzyl phthalate (BBP). Female rats were orally exposed from 14 days premating to 6 days postpartum. Male rats were exposed for 29 days. At 1000 mg\\/kg bw\\/day effects were found on body weight gain and food consumption, on spermatogenesis, time to conception, pregnancy rate,

A. H. Piersma; A. Verhoef; P. M. Dortant

1995-01-01

394

Tracheal epithelium in culture: A model for toxicity testing of inhaled molecules  

SciTech Connect

Rabbit trachea primary cultures have been developed as a model to evaluate the toxicity of noxious airborne pollutants. A mucociliary epithelium has been restored in vitro on collagen gel. Several general cytotoxicity assays (viability and growth inhibition) permit a first assessment for the acute toxicity of the tested molecules. More specific criteria such as measurement of the integrity of the epithelial barrier and inhibition of ciliary beat frequency allow to determine a specific impact of xenobiotics on the mucociliary epithelium in culture.

Romet-Haddad, S.; Marano, F.; Blanquart, C.; Baeza-Squiban, A. (Universite Paris (France))

1992-07-01

395

Determining the relative sensitivity of benthic diatoms to atrazine using rapid toxicity testing: a novel method.  

PubMed

Herbicides pose a potential threat to aquatic ecosystems, especially to phototrophic organisms such as benthic diatoms. Benthic diatoms may be a valuable indicator of the toxic impacts of herbicides in aquatic systems. However, this requires information on the herbicide sensitivity of a wide range of freshwater benthic diatom taxa. Unfortunately this information is only available for a limited number of species as current methods of developing new algae toxicity tests on individual taxa are lengthy and costly. To address this issue, we developed a new rapid toxicity test method to test natural benthic communities, from which the relative herbicide sensitivity of many individual taxa can be derived. This involved the collection of natural benthic communities from rocks in situ, which were placed directly into laboratory toxicity tests. Sensitivity data for several diatom genera in a 48 hour exposure toxicity test were produced, without the need for cultures or multiple site visits. After exposure to the highest treatment of atrazine (500 ?g L(-1)) there were significant declines of healthy cells in the most sensitive genera: Gomphonema declined by 74%, Amphora by 62%, Cymbella by 54% and Ulnaria by 34% compared to control levels. In contrast, the genera, Eunotia, Achnanthidium and Navicula, had no statistically significant decline in cell health. This method can identify the diatom taxa most at risk of herbicide toxicity within the natural benthic diatom community. The rapid toxicity testing method presented is a simple and effective method to obtain sensitivity data for multiple taxa within a natural benthic diatom community in a relatively short period of time. PMID:24742551

Wood, Rebecca J; Mitrovic, Simon M; Kefford, Ben J

2014-07-01

396

40 CFR 797.1330 - Daphnid chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...the ratio of daphnid biomass (grams, wet weight) to the volume (liters...periodically transferred to fresh test solution of the...or algal cells, dry weight) per liter dilution...rate is 15 mg food (dry weight) per liter...

2010-07-01

397

40 CFR 797.1400 - Fish acute toxicity test.  

Code of Federal Regulations, 2011 CFR

...best for organic test substances, while plastic holders are best for metals. The sample...stainless steel, and perfluorocarbon plastic should be used whenever possible. Concrete, fiberglass, or plastic (e.g., PVC) may be used for...

2011-07-01

398

40 CFR 797.1400 - Fish acute toxicity test.  

Code of Federal Regulations, 2012 CFR

...best for organic test substances, while plastic holders are best for metals. The sample...stainless steel, and perfluorocarbon plastic should be used whenever possible. Concrete, fiberglass, or plastic (e.g., PVC) may be used for...

2012-07-01

399

NEXT GENERATION SEDIMENT TOXICITY TESTING VIA DNA MICROARRAYS - PHASE I  

EPA Science Inventory

The current SBIR solicitation states that the EPA is seeking ?better sampling, analysis, and monitoring technologies? to improve hazardous waste management.  Development of new methods for testing contaminated sediments is an area of particular concern because many industri...

400

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...during testing. Any food utilized should support survival, growth and reproduction of the mysids. A recommended food is live Artemia spp. nauplii (approximately 48 hours old). (2) Facilities â(i) Apparatus. (A) Facilities which may be...

2009-07-01

401

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...during testing. Any food utilized should support survival, growth and reproduction of the mysids. A recommended food is live Artemia spp. nauplii (approximately 48 hours old). (2) Facilities â(i) Apparatus. (A) Facilities which may be...

2010-07-01

402

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...during testing. Any food utilized should support survival, growth and reproduction of the mysids. A recommended food is live Artemia spp. (48-hour-old nauplii). (2) Facilities â(i) Apparatus. (A) Facilities which may be needed to...

2010-07-01

403

Current Development in Reproductive Toxicity Testing of Pesticides  

EPA Science Inventory

A protocol to evaluate the potential developmental and reproductive effects of test chemicals has been developed by the Life Stages Task Force of the International Life Sciences Institute (ILSI)/Health and Environmental Sciences Institute (HESI) Agricultural Chemical Safety Asses...

404

Rapid toxicity screening tests for aquatic biota. 1. Methodology and experiments with Daphnia magna  

SciTech Connect

A promising new and rapid toxicity screening test was developed, the concept and principles of which are presented. The method consists of visual observation of in vivo inhibition of an enzymatic process, using a fluorescent substrate. Juvenile Daphnia magna was exposed to a toxicant dilution series for 1 h, after which the substrate was added and the enzymatic inhibition was observed visually, using a long-wave UV light. The 1-h EC50 results of 11 pure compounds are presented and compared to the conventional 24- and 48-h Daphnia magna EC50s. All 1-h fluorescence EC50s were of the same order of magnitude and correlated very well with the 24- and 48-h EC50s. The sensitivity and reproducibility of this cost-effective screening test were compared to those of the Microtox[reg sign] test. The scope for application and the potential of this new rapid toxicity screening test are evaluated.

Janssen, C.R.; Persoone, G. (State Univ. of Ghent (Belgium))

1993-04-01

405

Toxic Substances Control Act (TSCA) Test Submissions data base (TSCATS). Comprehensive update tape. Data file  

SciTech Connect

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 US 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.

Not Available

1990-03-01

406

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

SciTech Connect

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data are submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test data are 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.

NONE

1996-09-01

407

Toxic Substances Control Act (TSCA) test submissions database (TSCATS) - comprehensive update (on magnetic tape)  

SciTech Connect

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data are submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test data are 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, the submitting organization, and reason for submission of the test data.

NONE

1996-04-01

408

Toxic Substances Control Act (TSCA) test submissions database (tscats) - comprehensive update (on magnetic tape). Data file  

SciTech Connect

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data are submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test data are 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.

NONE

1995-12-31

409

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

SciTech Connect

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.

Not Available

1993-01-01

410

Toxic Substances Control Act (TSCA) Test Submissions Database (TSCATS) - comprehensive update (on magnetic tape). Data file  

SciTech Connect

The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data are submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test data are 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.

NONE

1996-12-31

411

A battery of toxicity tests as indicators of decontamination in composting oily waste.  

PubMed

Heterogeneous oily waste from an old dumping site was composted in three windrows constructed from different proportions of waste, sewage sludge, and bark. The objectives of this pilot study were to examine the usefulness of composting as a treatment method for this particular waste and to study decontamination in the composting process by using a battery of toxicity tests. Five samples from the windrow having intermediate oil concentrations were tested with toxicity tests based on microbes (Pseudomonas putida growth inhibition test, ToxiChromotest, MetPLATE, and three different modifications of a luminescent bacterial test), enzyme inhibition (reverse electron transport), plants (duckweed growth inhibition and red clover seed germination), and soil animals (Folsomia candida, Enchytraeus albidus, and Enchytraeus sp.). The luminescent bacterial tests were used as prescreening tests. Chemical analyses of samples were carried out simultaneously. Both toxicity and oil concentration, including those of polyaromatic hydrocarbons (PAHs), were reduced during composting and soil quality improved significantly. The total oil hydrocarbon concentration decreased from 90,000 to 19,000 mg/kg, measured with the IR method, in 4 months, and from 86,000 to 1400 mg/kg, measured with GC method. The concentration of PAHs decreased from 135 to 23.5 mg/kg. During the fourth month of composting (stabilization stage), the proportion of the heaviest oil fractions (asphaltenes) became dominant. Toxicity varied between different samples and between different bioassays; however, the first sample was significantly more toxic than the others, and most of the tests revealed a decrease in toxicity during the composting process. PMID:11023694

Juvonen, R; Martikainen, E; Schultz, E; Joutti, A; Ahtiainen, J; Lehtokari, M

2000-10-01

412

EFFECTS OF BEAUVERIA BASSIANA TO EMBRYOS OF THE INLAND SILVERSIDE (MENIDIA BERYLLINA)  

EPA Science Inventory

A chemical toxicity/teratogenicity test was adapted to assess potential adverse affect of a microbial pest control agent on a nontarget fish. eveloping embryos of inland silverside, Menidia beryllina, were exposed to conidiospores or the insect-pathogenic fungus, Beauveria bassia...

413

Scientific rationale for the selection of toxicity testing methods: human health assessment. [Literature analysis  

SciTech Connect

This document is the first of a two-part literature analysis of parameters associated with the various toxicity testing methods (test animal selection, pathology requirements, etc.). Acute, subchronic, chronic, and carcinogenic testing methods are covered; a discussion of some basic experimental considerations is also included. This report was prepared for the purpose of assisting and supporting the US Environmental Protecton Agency in its efforts to develop guidelines for more efficient and economical testing procedures.

Ross, R.H.; Ryon, M.G.; Daugherty, M.W.; Drury, J.S.; Ensminger, J.T.; Cone, M.V.

1980-12-01

414

APPROACH TO ENVIRONMENTAL RISK ASSESSMENT USING AVIAN TOXICITY TESTS (JOURNAL VERSION)  

EPA Science Inventory

Toxicity tests results are often condensed into a single endpoint (LC50) to facilitate their use in environmental management. The single number cannot distinguish between two tests with equal LC50s but dissimilar slopes at LC50 and it cannot describe the response at low and high ...

415

Perspectives on Validation of High-Throughput Assays Supporting 21st Century Toxicity Testing  

EPA Science Inventory

In vitro high-throughput screening (HTS) assays are seeing increasing use in toxicity testing. HTS assays can simultaneously test many chemicals but have seen limited use in the regulatory arena, in part because of the need to undergo rigorous, time-consuming formal validation. ...

416

Applications of Toxicity Testing as a Tool: Things we've Learned  

EPA Science Inventory

Whole effluent toxicity (WET) testing methodologies have been widely used to assess potential adverse effects of wastewater discharges on aquatic life in the United States since the 1970?s. The tests have been incorporated into the U.S. Environmental Protection Agency?s Water Qu...

417

Cumulative Bioluminescence - A Potential Rapid Test of Drilling Fluid Toxicity: Development Study  

Microsoft Academic Search

A new rapid test of drilling fluid toxicity is based on the spontaneous bioluminescence of Pyrocystis lunula, an easy-to-culture alga that vigorously responds to shear stress (mixing) by emitting a sharp burst of light. In contrast to other bioluminescence methods, a cumulative flux of light is measured with a photomultiplier that eliminates the effect of exposure time on test results.

A. K. Wojtanowicz; B. S. Shane; P. N. Greenlaw; A. V. Stiffey

1992-01-01

418

EVALUATION OF THE FATHEAD MINNOW SEVEN-DAY SUBCHRONIC TEST FOR ESTIMATING CHRONIC TOXICITY  

EPA Science Inventory

Renewal and flow-through subchronic tests were conducted on fathead minnows (Pimephales promelas) with nine chemicals and the results compared to early life stage (ELS) or life cycle toxicity values for one water type. In addition, ELS tests were conducted simultaneously with fou...

419

Effects of Low Dissolved Oxygen on Organisms Used in Freshwater Sediment Toxicity Tests  

EPA Science Inventory

This manuscript describes the results of tests to determine the tolerance of three benthic organisms to reduced dissolved oxygen (DO). These three organisms are those recommended by EPA for use in toxicity testing of contaminated sediments. The results of the exposures indicate ...

420

DREDGED MATERIAL EFFECTS ASSESSMENT: SINGLE-SPECIES TOXICITY/BIOACCUMULATION AND MACROBENTHOS COLONIZATION TESTS  

EPA Science Inventory

Toxicity tests and bioaccumulation tests conducted according to methods established by the U.S. Environmental Protection Agency/Corps of Engineers in 1977 have been used to evaluate potential environmental impacts of ocean disposal of dredged materials. ur objective was to compar...

421

SIMULTANEOUS MULTIPLE SPECIES TESTING: ACUTE TOXICITY OF 13 CHEMICALS TO 12 DIVERSE FRESHWATER AMPHIBIAN, FISH, AND INVERTEBRATE FAMILIES  

EPA Science Inventory

The test series developed methods for testing a compliment of aquatic organisms in a single test that satisfies the freshwater acute toxicity requirements for setting water quality criteria. Species tested included fathead minnows Pimephales promelas, rainbow trout Salmo gairdner...

422

Simultaneous Multiple Species Testing: Acute Toxicity of 13 Chemicals to 12 Diverse Freshwater Amphibian, Fish, and Invertebrate Families.  

National Technical Information Service (NTIS)

The test series developed methods for testing a compliment of aquatic organisms in a single test that satisfies the freshwater acute toxicity requirements for setting water quality criteria. Species tested included fathead minnows Pimephales promelas, rai...

G. W. Holcombe G. L. Phipps A. H. Sulaiman A. D. Hoffman

1987-01-01

423

Visible Embryo  

NSDL National Science Digital Library

a comprehensive resource of information on human development from conception to birth, designed for both medical student and interested lay people. The Visible Embryo offers a detailed pictorial account of normal and abnormal development.

Carmen Arbona (Mouseworks)

2006-01-30

424

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2013 CFR

...ii) Acclimation. (A) Any change in the temperature and chemistry of the water used for holding or culturing the test organisms...from a ground or surface water source, conductivity and total organic carbon (or chemical oxygen demand) shall be measured on...

2013-07-01

425

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2013 CFR

...ii) Acclimation. (A) Any change in the temperature and chemistry of the dilution water used for holding or culturing the test...from a ground or surface water source, conductivity and total organic carbon (or chemical oxygen demand) shall be measured on...

2013-07-01

426