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Sample records for embryo toxicity test

  1. Whole embryo culture and toxicity testing.

    PubMed

    Piersma, A H

    1993-11-01

    The use of post-implantation embryo culture in toxicity testing has been the subject of research as well as debate. Advantages of the method include reduced animal use, and reduced cost and time in comparison with in vivo testing. In addition, the method yields many developmental endpoints: it allows the direct and controlled addition of small amounts of compounds, and the incorporation of metabolizing systems is possible. Disadvantages include the technical skill required, the restricted culture duration, the artificial route of administration of test compounds and the absence of the maternal compartment (and hence the absence of a measure for adult toxicity). Several studies using a variety of compounds have shown promising results with respect to correlations between in vivo effects and the outcome of embryo culture. The question of how a meaningful validation study should be designed is still a matter of dispute. Issues under discussion include: the purpose of validation, culture conditions, endpoint definition, choice of compounds to be tested, the status of in vivo data on test compounds, presentation of results, double-blind and interlaboratory design, and the position of the test within a testing strategy. The validity of whole embryo culture as a toxicity screening test is likely to vary considerably between classes of compounds. Therefore, validation studies with larger sets of related compounds may be more meaningful than those with many unrelated compounds. Whole embryo culture may provide a significant contribution to risk assessment by use in screening, and for mechanistic, structure-activity, and dose-response studies. PMID:20732278

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

    SciTech Connect

    Lee, R.; O`Malley, K.

    1995-12-31

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

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

    PubMed

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

    2012-06-01

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

  4. Fish embryo toxicity test: identification of compounds with weak toxicity and analysis of behavioral effects to improve prediction of acute toxicity for neurotoxic compounds.

    PubMed

    Klüver, Nils; König, Maria; Ortmann, Julia; Massei, Riccardo; Paschke, Albrecht; Kühne, Ralph; Scholz, Stefan

    2015-06-01

    The fish embryo toxicity test has been proposed as an alternative for the acute fish toxicity test, but concerns have been raised for its predictivity given that a few compounds have been shown to exhibit a weak acute toxicity in the fish embryo. In order to better define the applicability domain and improve the predictive capacity of the fish embryo test, we performed a systematic analysis of existing fish embryo and acute fish toxicity data. A correlation analysis of a total of 153 compounds identified 28 compounds with a weaker or no toxicity in the fish embryo test. Eleven of these compounds exhibited a neurotoxic mode of action. We selected a subset of eight compounds with weaker or no embryo toxicity (cyanazine, picloram, aldicarb, azinphos-methyl, dieldrin, diquat dibromide, endosulfan, and esfenvalerate) to study toxicokinetics and a neurotoxic mode of action as potential reasons for the deviating fish embryo toxicity. Published fish embryo LC50 values were confirmed by experimental analysis of zebrafish embryo LC50 according to OECD guideline 236. Except for diquat dibromide, internal concentration analysis did not indicate a potential relation of the low sensitivity of fish embryos to a limited uptake of the compounds. Analysis of locomotor activity of diquat dibromide and the neurotoxic compounds in 98 hpf embryos (exposed for 96 h) indicated a specific effect on behavior (embryonic movement) for the neurotoxic compounds. The EC50s of behavior for neurotoxic compounds were close to the acute fish toxicity LC50. Our data provided the first evidence that the applicability domain of the fish embryo test (LC50s determination) may exclude neurotoxic compounds. However, neurotoxic compounds could be identified by changes in embryonic locomotion. Although a quantitative prediction of acute fish toxicity LC50 using behavioral assays in fish embryos may not yet be possible, the identification of neurotoxicity could trigger the conduction of a conventional fish

  5. Adapting the medaka embryo assay to a high-throughput approach for developmental toxicity testing.

    PubMed

    Oxendine, Sharon L; Cowden, John; Hinton, David E; Padilla, Stephanie

    2006-09-01

    Chemical exposure during embryonic development may cause persistent effects, yet developmental toxicity data exist for very few chemicals. Current testing procedures are time consuming and costly, underlining the need for rapid and low cost screening strategies. While in vitro methods are useful for screening, these methods do not replicate all the intricacies of embryonic development and should ideally be complemented by an in vivo screening strategy. In this study, we modify a medaka fish embryo assay to meet the requirements of high-throughput, developmental toxicant testing in vivo. The Japanese medaka (Oryzias latipes) offers several advantages over traditional mammalian model systems, including economic husbandry, high fecundity, and rapid ex utero development. In most studies where fish eggs are exposed to a chemical, the exposure takes place in a common vessel, with many embryos being exposed to the same solution. This type of design is not amenable to high-throughput methodology, does not allow the investigator to follow the same embryo throughout gestation, and may confound statistical analysis of the results. Therefore, we developed a 96-well microtiter plate method to facilitate exposure of individual medaka embryos in single wells and compared this approach to the common vessel method using the industrial solvent dimethyl sulfoxide (DMSO) as the test compound. At lower DMSO concentrations (0% or 1%), the 96-well microtiter plate assay replicated results obtained using the common vessel exposure method. There was, however, increased lethality and decreased hatching rate in the bottle-reared embryos treated with the higher DMSO concentrations (5% or 10%). Because the embryos reared in the 96-well microtiter plates never showed increased adverse effects (as compared to the bottle-reared embryos) at any DMSO concentration, we conclude that the 96-well microtiter plate assay provides a rapid and efficient alternative for developmental toxicity screens that

  6. 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...

  7. 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...

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2014-05-01

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

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

    PubMed

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

    2014-10-01

    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

  11. A test for evaluating the toxicity of oils, dispersants, and oil biodegradation products to embryos of grass shrimp (Palaemonetes pugio)

    SciTech Connect

    Foss, S.S.; Fisher, W.S.; Chapman, P.J.; Shelton, M.

    1994-12-31

    A test has been developed to determine the toxicity of oil, commercial oil dispersants, and oil biodegradation products to embryos of the grass shrimp, Palaemonetes pugio. The system has several advantages over traditional toxicity tests: Embryos are exposed separately in glass tubes eliminating interaction between individuals, they do not require feeding, are easily examined, and require low volumes of test toxicant. Additionally, tests can be performed using artificial sea salts and adult P. pugio can be maintained and cultured year round in the laboratory. Toxicity tests demonstrated that oil dispersants increased the toxicity of the water-soluble fraction of No. 2 Fuel Oil with estimated LC50 values approximating those obtained with the 7d chronic tests using Mysidopsis bahia. Embryos exposed to neutral fractions derived by microbial degradation of weathered Prudhoe Bay crude oil showed toxicity of metabolic products at relatively low concentrations and cause virtually 100% mortality within a narrow time interval. P. pugio embryos were especially responsive to oil metabolites, exhibiting high sensitivity and low variability. All tests showed a consistently high survival (90--100%) of control embryos to hatch under a variety of temperatures and salinities; embryos at any given test condition usually hatched within 24h of one another.

  12. A high throughput passive dosing format for the Fish Embryo Acute Toxicity test.

    PubMed

    Vergauwen, Lucia; Schmidt, Stine N; Stinckens, Evelyn; Maho, Walid; Blust, Ronny; Mayer, Philipp; Covaci, Adrian; Knapen, Dries

    2015-11-01

    High throughput testing according to the Fish Embryo Acute Toxicity (FET) test (OECD Testing Guideline 236) is usually conducted in well plates. In the case of hydrophobic test substances, sorptive and evaporative losses often result in declining and poorly controlled exposure conditions. Therefore, our objective was to improve exposure conditions in FET tests by evaluating a passive dosing format using silicone O-rings in standard 24-well polystyrene plates. We exposed zebrafish embryos to a series of phenanthrene concentrations until 120h post fertilization (hpf), and obtained a linear dilution series. We report effect values for both mortality and sublethal morphological effects based on (1) measured exposure concentrations, (2) (lipid normalized) body residues and (3) chemical activity. The LC50 for 120hpf was 310μg/L, CBR50 (critical body residue) was 2.72mmol/kg fresh wt and La50 (lethal chemical activity) was 0.047. All values were within ranges expected for baseline toxicity. Impaired swim bladder inflation was the most pronounced morphological effect and swimming activity was reduced in all exposure concentrations. Further analysis showed that the effect on swimming activity was not attributed to impaired swim bladder inflation, but rather to baseline toxicity. We conclude that silicone O-rings (1) produce a linear dilution series of phenanthrene in the 120hpf FET test, (2) generate and maintain aqueous concentrations for reliable determination of effect concentrations, and allow for obtaining mechanistic toxicity information, and (3) cause no toxicity, demonstrating its potential as an extension of the FET test when testing hydrophobic chemicals. PMID:26026258

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

    PubMed

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

    2014-08-01

    The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (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.

  14. Comparison of toxicity test methods using embryos of the grass shrimp, Palaemonetes pugio

    SciTech Connect

    Rayburn, J.R.; Fisher, W.S.; Foss, S.S.; Glas, P.S.

    1995-12-31

    The embryos of the grass shrimp (Palaemonetes pugio) have shown sensitivity to the water soluble fraction of number 2 fuel oil (WSF{sub oil}). To determine the repeatability and versatility of the grass shrimp in bioassays, detailed concentration-response curves were performed using altered test methods. These alterations were to make the test system easier to use, require less volume of toxic material and to shorten the time of the assay. LC50 values for each method were obtained. The methods evaluated the differences between altering time of exposure from 12 to 4 days. The 4-day assay in 24-well plastic plates included the time of hatch, a critical life stage of these embryos. The average 12-day LC50 in the glass Leighton tubes was 11.8% VN WSF{sub oil}. The coefficient of variation of the individual test methods were approximately 25%, showing that the repeatability was reasonable for bioassays. These results show that a 4-day assay is practical for screening for the detection of number 2 fuel oil contamination. However, the 12-day assay may be necessary for detection of developmental abnormalities.

  15. Automated Lab-on-a-Chip Technology for Fish Embryo Toxicity Tests Performed under Continuous Microperfusion (μFET).

    PubMed

    Zhu, Feng; Wigh, Adriana; Friedrich, Timo; Devaux, Alain; Bony, Sylvie; Nugegoda, Dayanthi; Kaslin, Jan; Wlodkowic, Donald

    2015-12-15

    The fish embryo toxicity (FET) biotest has gained popularity as one of the alternative approaches to acute fish toxicity tests in chemical hazard and risk assessment. Despite the importance and common acceptance of FET, it is still performed in multiwell plates and requires laborious and time-consuming manual manipulation of specimens and solutions. This work describes the design and validation of a microfluidic Lab-on-a-Chip technology for automation of the zebrafish embryo toxicity test common in aquatic ecotoxicology. The innovative device supports rapid loading and immobilization of large numbers of zebrafish embryos suspended in a continuous microfluidic perfusion as a means of toxicant delivery. Furthermore, we also present development of a customized mechatronic automation interface that includes a high-resolution USB microscope, LED cold light illumination, and miniaturized 3D printed pumping manifolds that were integrated to enable time-resolved in situ analysis of developing fish embryos. To investigate the applicability of the microfluidic FET (μFET) in toxicity testing, copper sulfate, phenol, ethanol, caffeine, nicotine, and dimethyl sulfoxide were tested as model chemical stressors. Results obtained on a chip-based system were compared with static protocols performed in microtiter plates. This work provides evidence that FET analysis performed under microperfusion opens a brand new alternative for inexpensive automation in aquatic ecotoxicology.

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

    SciTech Connect

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

    1993-01-01

    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.)

  17. Screening of Toxic Effects of Bisphenol A and Products of Its Degradation: Zebrafish (Danio rerio) Embryo Test and Molecular Docking.

    PubMed

    Makarova, Katerina; Siudem, Pawel; Zawada, Katarzyna; Kurkowiak, Justyna

    2016-10-01

    Bisphenol A (BPA) acts as an endocrine-disrupting compound even at a low concentration. Degradation of BPA could lead to the formation of toxic products. In this study, we compare the toxicity of BPA and seven intermediate products of its degradation. The accuracy of three molecular docking programs (Surflex, Autodock, and Autodock Vina) in predicting the binding affinities of selected compounds to human (ERα, ERβ, and ERRγ) and zebrafish (ERα, ERRγA, and ERRγB) estrogen and estrogen-related receptors was evaluated. The docking experiments showed that 4-isopropylphenol could have similar toxicity to that of BPA due to its high affinity to ERRγ and ERRγB and high octanol-water partitioning coefficient. The least toxic compounds were hydroquinone and phenol. Those compounds as well as BPA were screened in the zebrafish (Danio rerio) embryo test. 4-isopropylphenol had the strongest toxic effect on zebrafish embryos and caused 100% lethality shortly after exposure. BPA caused the delay in development, multiple deformations, and low heartbeats (30 bps), whereas hydroquinone had no impact on the development of the zebrafish embryo. Thus, the results of zebrafish screening are in good agreement with our docking experiment. The molecular docking could be used to screen the toxicity of other xenoestrogens and their products of degradation. PMID:27486708

  18. Screening of Toxic Effects of Bisphenol A and Products of Its Degradation: Zebrafish (Danio rerio) Embryo Test and Molecular Docking.

    PubMed

    Makarova, Katerina; Siudem, Pawel; Zawada, Katarzyna; Kurkowiak, Justyna

    2016-10-01

    Bisphenol A (BPA) acts as an endocrine-disrupting compound even at a low concentration. Degradation of BPA could lead to the formation of toxic products. In this study, we compare the toxicity of BPA and seven intermediate products of its degradation. The accuracy of three molecular docking programs (Surflex, Autodock, and Autodock Vina) in predicting the binding affinities of selected compounds to human (ERα, ERβ, and ERRγ) and zebrafish (ERα, ERRγA, and ERRγB) estrogen and estrogen-related receptors was evaluated. The docking experiments showed that 4-isopropylphenol could have similar toxicity to that of BPA due to its high affinity to ERRγ and ERRγB and high octanol-water partitioning coefficient. The least toxic compounds were hydroquinone and phenol. Those compounds as well as BPA were screened in the zebrafish (Danio rerio) embryo test. 4-isopropylphenol had the strongest toxic effect on zebrafish embryos and caused 100% lethality shortly after exposure. BPA caused the delay in development, multiple deformations, and low heartbeats (30 bps), whereas hydroquinone had no impact on the development of the zebrafish embryo. Thus, the results of zebrafish screening are in good agreement with our docking experiment. The molecular docking could be used to screen the toxicity of other xenoestrogens and their products of degradation.

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

    PubMed

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

    2014-11-01

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

  20. ADAPTING THE MEDAKA EMBRYO ASSAY TO A HIGH-THROUGHPUT APPROACH FOR DEVELOPMENTAL TOXICITY TESTING.

    EPA Science Inventory

    Chemical exposure during embryonic development may cause persistent effects, yet developmental toxicity data exist for very few chemicals. Current testing procedures are time consuming and costly, underlining the need for rapid and low cost screening strategies. While in vitro ...

  1. Development of an embryo toxicity test with the pond snail Lymnaea stagnalis using the model substance tributyltin and common solvents.

    PubMed

    Bandow, Cornelia; Weltje, Lennart

    2012-10-01

    The development of a chronic mollusc toxicity test is a current work item on the agenda of the OECD. The freshwater pond snail Lymnaea stagnalis is one of the candidate snail species for such a test. This paper presents a 21-day chronic toxicity test with L. stagnalis, focussing on embryonic development. Eggs were collected from freshly laid egg masses and exposed individually until hatching. The endpoints were hatching success and mean hatching time. Tributyltin (TBT), added as TBT-chloride, was chosen as model substance. The selected exposure concentrations ranged from 0.03 to 10 μg TBT/L (all as nominal values) and induced the full range of responses. The embryos were sensitive to TBT (the NOEC for mean hatching time was 0.03 μg TBT/L and the NOEC for hatching success was 0.1 μg TBT/L). In addition, data on maximum limit concentrations of seven common solvents, recommended in OECD aquatic toxicity testing guidelines, are presented. Among the results, further findings as average embryonic growth and mean hatching time of control groups are provided. In conclusion, the test presented here could easily be standardised and is considered useful as a potential trigger to judge if further studies, e.g. a (partial) life-cycle study with molluscs, should be conducted.

  2. A novel system for embryo-larval toxicity testing of pelagic fish: Applications for impact assessment of Deepwater Horizon crude oil.

    PubMed

    Stieglitz, John D; Mager, Edward M; Hoenig, Ronald H; Alloy, Matthew; Esbaugh, Andrew J; Bodinier, Charlotte; Benetti, Daniel D; Roberts, Aaron P; Grosell, Martin

    2016-11-01

    Key differences in the developmental process of pelagic fish embryos, in comparison to embryos of standard test fish species, present challenges to obtaining sufficient control survival needed to successfully perform traditional toxicity testing bioassays. Many of these challenges relate to the change in buoyancy, from positive to negative, of pelagic fish embryos that occurs just prior to hatch. A novel exposure system, the pelagic embryo-larval exposure chamber (PELEC), has been developed to conduct successful bioassays on the early life stages (ELSs; embryos/larvae) of pelagic fish. Using this unique recirculating upwelling system, it was possible to significantly improve control survival in pelagic fish ELS bioassays compared to commonly used static exposure methods. Results demonstrate that control performance of mahi-mahi (Coryphaena hippurus) embryos in the PELEC system, measured as percent survival after 96-hrs, significantly outperformed agitated static exposure and static exposure systems. Similar significant improvements in 72-hr control survival were obtained with yellowfin tuna (Thunnus albacares). The PELEC system was subsequently used to test the effects of photo-induced toxicity of crude oil to mahi-mahi ELSs over the course of 96-hrs. Results indicate a greater than 9-fold increase in toxicity of Deepwater Horizon (DWH) crude oil during co-exposure to ambient sunlight compared to filtered ambient sunlight, revealing the importance of including natural sunlight in 96-hr DWH crude oil bioassays as well as the PELEC system's potential application in ecotoxicological assessments. PMID:27505137

  3. Developmental arrest in grass shrimp embryos exposed to selected toxicants

    SciTech Connect

    Wilson, J.E.H.

    1998-12-31

    Excised embryos of the grass shrimp (Palaemonetes pugio) were exposed to single pulse concentrations of selected pollutants for 4 days. The following toxicity endpoints were monitored: rate of embryonic development, embryo mortality, and types of embryo malformation. Each endpoint exhibited concentration--response relationships which were modified by the embryonic age at which exposure commenced. Developmental retardation of up to 3 days was effected by phenol at 0.01% (V/V) and complete developmental arrest occurred at 0.05% and 0.1% (V/V). Similarly for methylene chloride, developmental retardation of 1003 days were observed at 0.1% (V/V) depending on the age of the embryos at the start of the tests. The morphological abnormalities of the embryos are described. The ecological significance of these findings and implications for the development of short-term toxicity tests using grass shrimp embryos are discussed.

  4. Toxicity of chlorine to zebrafish embryos.

    PubMed

    Kent, Michael L; Buchner, Cari; Barton, Carrie; Tanguay, Robert L

    2014-01-16

    Surface disinfection of fertilized fish eggs is widely used in aquaculture to reduce extraovum pathogens that may be released from brood fish during spawning, and this is routinely used in zebrafish Danio rerio research laboratories. Most laboratories use approximately 25 to 50 ppm unbuffered chlorine solution for 5 to 10 min. Treatment of embryos with chlorine has significant germicidal effects for many Gram-negative bacteria, viruses, and trophozoite stages of protozoa, but is less effective against cyst or spore stages of protozoa and certain Mycobacterium spp. Therefore, we evaluated the toxicity of unbuffered and buffered chlorine solutions to embryos exposed at 6 or 24 h post-fertilization (hpf) to determine whether higher concentrations can be used for treating zebrafish embryos. Most of our experiments entailed using an outbred line (5D), with both mortality and malformations as endpoints. We found that 6 hpf embryos consistently were more resistant than 24 hpf embryos to the toxic effects of chlorine. Chlorine is more toxic and germicidal at lower pH, and chlorine causes elevated pH. Consistent with this, we found that unbuffered chlorine solutions (pH ca. 8-9) were less toxic at corresponding concentrations than solutions buffered to pH 7. Based on our findings here, we recommend treating 6 hpf embryos for 10 min and 24 hpf embryos for 5 min with unbuffered chlorine solution at 100 ppm.

  5. Ecotoxicological studies of environmental samples from Buenos Aires area using a standardized amphibian embryo toxicity test (AMPHITOX).

    PubMed

    Herkovits, Jorge; Perez-Coll, Cristina; Herkovits, Francisco D

    2002-01-01

    The toxicity of 34 environmental samples from potentially polluted and reference stations were evaluated by means of the AMPHITOX test from acute to chronic exposure according to the toxicity found in each sample. The samples were obtained from surface and ground water, leaches, industrial effluents and soils. The data, expressed in acute, short-term chronic and chronic Toxicity Units (TUa, TUstc and TUc) resulted in a maximal value of 1000 TUc, found in a leach, while the lower toxicity value was 1.4 TUa corresponding to two surface water samples. In five samples (four providing from reference places) no toxicity was detected. The results point out the possibility of evaluating the toxicity of a wide diversity of samples by means of AMPHITOX as a customized toxicity test. The fact that almost all samples with suspected toxicity in rivers and streams from the Metropolitan area of Buenos Aires city resulted toxic, indicates the need of enhanced stewardship of chemical substances for environmental and human health protection purposes. PMID:11808551

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

    PubMed

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

    2013-01-15

    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

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

    PubMed

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

    2014-08-01

    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.

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

    PubMed

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

    2014-08-01

    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

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

    PubMed

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

    2012-06-01

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

  10. 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

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

    2011-06-01

    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.

  11. Toxic effects of colloidal nanosilver in zebrafish embryos.

    PubMed

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

    2014-05-01

    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.

  12. Toxicity of trihalomethanes to common carp embryos

    SciTech Connect

    Mattice, J.S.; Tsai, S.C.; Burch, M.B.; Beauchamp, J.J.

    1981-03-01

    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.

  13. The fish embryo toxicity test as a replacement for the larval growth and survival test: A comparison of test sensitivity and identification of alternative endpoints in zebrafish and fathead minnows.

    PubMed

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

    2015-06-01

    The fish embryo toxicity (FET) test has been proposed as an alternative to the larval growth and survival (LGS) test. The objectives of the present study were to evaluate the sensitivity of the FET and LGS tests in fathead minnows (Pimephales promelas) and zebrafish (Danio rerio) and to determine if the inclusion of sublethal metrics as test endpoints could enhance test utility. In both species, LGS and FET tests were conducted using 2 simulated effluents. A comparison of median lethal concentrations determined via each test revealed significant differences between test types; however, it could not be determined which test was the least and/or most sensitive. At the conclusion of each test, developmental abnormalities and the expression of genes related to growth and toxicity were evaluated. Fathead minnows and zebrafish exposed to mock municipal wastewater-treatment plant effluent in a FET test experienced an increased incidence of pericardial edema and significant alterations in the expression of genes including insulin-like growth factors 1 and 2, heat shock protein 70, and cytochrome P4501A, suggesting that the inclusion of these endpoints could enhance test utility. The results not only show the utility of the fathead minnow FET test as a replacement for the LGS test but also provide evidence that inclusion of additional endpoints could improve the predictive power of the FET test.

  14. Evaluation of MWNT toxic effects on daphnia and zebrafish embryos

    NASA Astrophysics Data System (ADS)

    Olasagasti, Maider; Alvarez, Noelia; Vera, Carolina; Rainieri, Sandra

    2009-05-01

    Organisms of daphnia (Daphnia magna) and zebrafish (Danio rerio) embryos were exposed to a range of different concentrations of COOH-functionalized MWCNT suspended in an aqueous solution of Tween 20. Immobilization of daphnia and growth retardation, inhibition and malformation of zebrafish embryos were the endpoints tested after 24 and 48 hours. Immobilization of daphnia could be observed from 3 to 16 ppm and an increasing mortality of zebrafish embryo was detected at all the concentration tested. To identify more subtle toxic effects, we took advantage of the extensive information available on the zebrafish genome and monitored by RT-PCR the expression patterns of different zebrafish genes that could act as toxicity bio-markers. At some of the concentrations tested, changes in the expression profiles of the genes examined were detected. Our results suggest that MWCNT could potentially represent a risk to human health and environment, therefore a wider range of concentrations and further testing of this molecules should be carried out to define possible limitations in their use.

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

    PubMed

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

    2011-06-15

    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.

  16. Toxic effects of silica nanoparticles on zebrafish embryos and larvae.

    PubMed

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

    2013-01-01

    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. PMID:24058598

  17. Chiral PCB 91 and 149 Toxicity Testing in Embryo and Larvae (Danio rerio): Application of Targeted Metabolomics via UPLC-MS/MS

    NASA Astrophysics Data System (ADS)

    Chai, Tingting; Cui, Feng; Yin, Zhiqiang; Yang, Yang; Qiu, Jing; Wang, Chengju

    2016-09-01

    In this study, we aimed to investigate the dysfunction of zebrafish embryos and larvae induced by rac-/(+)-/(‑)- PCB91 and rac-/(‑)-/(+)- PCB149. UPLC-MS/MS (Ultra-performance liquid chromatography coupled with mass spectrometry) was employed to perform targeted metabolomics analysis, including the quantification of 22 amino acids and the semi-quantitation of 22 other metabolites. Stereoselective changes in target metabolites were observed in embryos and larvae after exposure to chiral PCB91 and PCB149, respectively. In addition, statistical analyses, including PCA and PLS-DA, combined with targeted metabolomics were conducted to identify the characteristic metabolites and the affected pathways. Most of the unique metabolites in embryos and larvae after PCB91/149 exposure were amino acids, and the affected pathways for zebrafish in the developmental stage were metabolic pathways. The stereoselective effects of PCB91/149 on the metabolic pathways of zebrafish embryos and larvae suggest that chiral PCB91/149 exposure has stereoselective toxicity on the developmental stages of zebrafish.

  18. Chiral PCB 91 and 149 Toxicity Testing in Embryo and Larvae (Danio rerio): Application of Targeted Metabolomics via UPLC-MS/MS

    PubMed Central

    Chai, Tingting; Cui, Feng; Yin, Zhiqiang; Yang, Yang; Qiu, Jing; Wang, Chengju

    2016-01-01

    In this study, we aimed to investigate the dysfunction of zebrafish embryos and larvae induced by rac-/(+)-/(−)- PCB91 and rac-/(−)-/(+)- PCB149. UPLC-MS/MS (Ultra-performance liquid chromatography coupled with mass spectrometry) was employed to perform targeted metabolomics analysis, including the quantification of 22 amino acids and the semi-quantitation of 22 other metabolites. Stereoselective changes in target metabolites were observed in embryos and larvae after exposure to chiral PCB91 and PCB149, respectively. In addition, statistical analyses, including PCA and PLS-DA, combined with targeted metabolomics were conducted to identify the characteristic metabolites and the affected pathways. Most of the unique metabolites in embryos and larvae after PCB91/149 exposure were amino acids, and the affected pathways for zebrafish in the developmental stage were metabolic pathways. The stereoselective effects of PCB91/149 on the metabolic pathways of zebrafish embryos and larvae suggest that chiral PCB91/149 exposure has stereoselective toxicity on the developmental stages of zebrafish. PMID:27629264

  19. Chiral PCB 91 and 149 Toxicity Testing in Embryo and Larvae (Danio rerio): Application of Targeted Metabolomics via UPLC-MS/MS.

    PubMed

    Chai, Tingting; Cui, Feng; Yin, Zhiqiang; Yang, Yang; Qiu, Jing; Wang, Chengju

    2016-01-01

    In this study, we aimed to investigate the dysfunction of zebrafish embryos and larvae induced by rac-/(+)-/(-)- PCB91 and rac-/(-)-/(+)- PCB149. UPLC-MS/MS (Ultra-performance liquid chromatography coupled with mass spectrometry) was employed to perform targeted metabolomics analysis, including the quantification of 22 amino acids and the semi-quantitation of 22 other metabolites. Stereoselective changes in target metabolites were observed in embryos and larvae after exposure to chiral PCB91 and PCB149, respectively. In addition, statistical analyses, including PCA and PLS-DA, combined with targeted metabolomics were conducted to identify the characteristic metabolites and the affected pathways. Most of the unique metabolites in embryos and larvae after PCB91/149 exposure were amino acids, and the affected pathways for zebrafish in the developmental stage were metabolic pathways. The stereoselective effects of PCB91/149 on the metabolic pathways of zebrafish embryos and larvae suggest that chiral PCB91/149 exposure has stereoselective toxicity on the developmental stages of zebrafish. PMID:27629264

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

    NASA Astrophysics Data System (ADS)

    Yang, Zhihui; Zhang, Xiangjing; Cai, Zhonghua

    2009-05-01

    As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of H. diversicolor supertexta can be used to indicate toxicity of the PAEs.

  1. Toxicity of cryoprotectants agents in freshwater prawn embryos of Macrobrachium amazonicum.

    PubMed

    Ferreira, Arthur Vinícius Lourenço; Castro, Elias José Teles; Barbosa, Mariana Silva Alves; de Sousa, Míriam Luzia Nogueira Martins; de Araújo Neto, Manoel Paiva; Filho, Aldeney Andrade Soares; de Souza Sampaio, Celia Maria

    2015-12-01

    The process of cooling and cryopreservation of prawn embryos is a viable alternative for a continuous supply of larvae for freshwater prawn farming ponds. However, studies involving the application of those techniques as well as on toxicity of cryoprotectants in freshwater prawn embryos are scarce. Thus, this study aims to test the toxicity of methylic alcohol (MET), dimethyl sulfoxide (DMSO) and ethylene glycol (EG) on Macrobrachium amazonicum embryos. For the present experiment, pools of embryos were taken from 15 M. amazonicum females and were divided into three groups and tested in duplicate at concentrations of 10, 5, 3; 1, 0.5 or 0.1%. Toxicity tests were conducted for 24 h in Falcon® pipes to obtain the lethal concentration for 50% of the larvae (LC50). After the set period for testing, random samples of embryos were removed for morphological analysis under stereoscopic microscopes. Results were analysed using analysis of variance (ANOVA) and Tukey's test at a 5% significance level and Trimmed Spearman-Karber Analysis to determine LC50-24 h. DMSO toxicity tests revealed that 5% and 10% concentrations showed the highest toxicity and differed from the control (P ≤ 0.05), 24h-LC50 was 437.4 ± 14.4 µL. MET was less toxic among the tested cryoprotectants and concentrations did not allow the determination of its LC50-24h. For tests with EG, concentrations of 3, 5 or 10% solutions resulted in a 100% mortality to tested embryos; EG was the tested cryoprotectant with the highest toxicity, with an LC50-24h average of 81.91 ± 35.3 µl. PMID:25255785

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

    SciTech Connect

    Jackim, E.; Nacci, D.

    1984-01-01

    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 samples.

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

    PubMed

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

    2014-01-01

    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.

  4. 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...

  5. Comparative toxicity of four chemically dispersed and undispersed crude oils to rainbow trout embryos.

    PubMed

    Wu, Dongmei; Wang, Zhendi; Hollebone, Bruce; McIntosh, Stephen; King, Tom; Hodson, Peter V

    2012-04-01

    The chronic toxicity of crude oil to fish embryos depends on the chemical constituents of the test oil and on factors that control the exposure of embryos to those constituents. The partitioning of chemicals from oil to water depends on the surface area of oil exposed to water and thus on the susceptibility of oil to be dispersed into droplets. The chronic toxicity of four different crude oils to embryos of rainbow trout (Oncorhynchus mykiss) was measured by exposure to the water-accommodated fraction (WAF; no droplet formation) and to the chemically enhanced WAF (CEWAF) of each oil. When effects were compared with the amount of WAF or CEWAF added to test solutions, chemical dispersion increased toxicity dramatically, by >35 to >300-fold, with the smallest difference measured for the lightest and least viscous oil. When effects were compared with measured concentrations of oil in test solutions, there were no differences in toxicity between WAF and CEWAF treatments, indicating that chemical dispersion promoted droplet formation and the partitioning of hydrocarbons from oil to water. On a dilution basis, the differences in toxicity among the four oils were correlated with the concentrations in oil of polynuclear aromatic hydrocarbons (PAH), particularly those with three to five rings, and with their viscosity, an index of dispersibility. However, when PAH concentrations were measured in solution, toxicity did not vary substantially among the four oils, suggesting that the PAH of each oil had equivalent toxicities and that differences in toxicity represented differences in dispersability. PMID:22213001

  6. Developmental toxicity assay using high content screening of zebrafish embryos

    PubMed Central

    Lantz-McPeak, Susan; Guo, Xiaoqing; Cuevas, Elvis; Dumas, Melanie; Newport, Glenn D.; Ali, Syed F.; Paule, Merle G.; Kanungo, Jyotshna

    2016-01-01

    Typically, time-consuming standard toxicological assays using the zebrafish (Danio rerio) embryo model evaluate mortality and teratogenicity after exposure during the first 2 days post-fertilization. Here we describe an automated image-based high content screening (HCS) assay to identify the teratogenic/embryotoxic potential of compounds in zebrafish embryos in vivo. Automated image acquisition was performed using a high content microscope system. Further automated analysis of embryo length, as a statistically quantifiable endpoint of toxicity, was performed on images post-acquisition. The biological effects of ethanol, nicotine, ketamine, caffeine, dimethyl sulfoxide and temperature on zebrafish embryos were assessed. This automated developmental toxicity assay, based on a growth-retardation endpoint should be suitable for evaluating the effects of potential teratogens and developmental toxicants in a high throughput manner. This approach can significantly expedite the screening of potential teratogens and developmental toxicants, thereby improving the current risk assessment process by decreasing analysis time and required resources. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. PMID:24871937

  7. Virtual Embryo: Systems Modeling in Developmental Toxicity

    EPA Science Inventory

    High-throughput and high-content screening (HTS-HCS) studies are providing a rich source of data that can be applied to in vitro profiling of chemical compounds for biological activity and potential toxicity. EPA’s ToxCast™ project, and the broader Tox21 consortium, in addition t...

  8. 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...

  9. In Vivo Nanotoxicity Testing using the Zebrafish Embryo Assay

    PubMed Central

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

    2013-01-01

    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. PMID:24179674

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

    PubMed Central

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

    2014-01-01

    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

  11. Combined endosulfan and cypermethrin-induced toxicity to embryo-larval development of Rhinella arenarum.

    PubMed

    Svartz, Gabriela V; Aronzon, Carolina M; Pérez Coll, Cristina S

    2016-01-01

    The combined effects of two widely used pesticides, endosulfan and cypermethrin, on survival of embryo-larval development of the South American toad (Rhinella arenarum) were examined. The toxicity bioassays were performed according to the AMPHITOX test. Embryos and larvae were exposed to mixtures of these pesticides at equitoxic ratios from acute or chronic exposure to evaluate interaction effects. The results were analyzed using both Marking's additive index and combination index (CI)-isobologram methods. Acute (96-h) and intermediate (168-h) toxicity of endosulfan-cypermethrin mixtures remained almost constant for larvae and embryos, but when exposure duration was increased, there was a significant elevation in toxicity, obtaining chronic (240-h) no-observed-effect concentrations (NOEC) values of 0.045 and 0.16 mg/L for embryos and larvae, respectively. These are environmentally relevant concentrations that reflect a realistic risk of this pesticide mixture to this native amphibian species. The toxicity increment with the exposure duration was coincident with the central nervous system development on embryos reaching the larval period, the main target organ of these pesticides. The interactions of the pesticide mixtures at acute and chronic exposure were antagonistic for embryo development (CI > 1), and additive (CI = 1) for larvae, while chronic exposure interactions were synergistic (CI < 1) for both developmental periods. Data indicated that endosulfan-cypermethrin mixtures resulted in different interaction types depending on duration and developmental stage exposed. As a general pattern and considering conditions of overall developmental period and chronic exposure, this pesticide mixture usually applied in Argentine crop fields is synergistic with respect to toxicity for this native amphibian species.

  12. Virtual Embryo: Systems Modeling in Developmental Toxicity

    EPA Science Inventory

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to chemical profiling to address sensitivity and specificity of molecular targets, biological pathways, cellular and developmental processes. EPA’s ToxCast project is testing 960 uniq...

  13. Ultraviolet Radiation Enhances the Toxicity of Deepwater Horizon Oil to Mahi-mahi (Coryphaena hippurus) Embryos.

    PubMed

    Alloy, Matthew; Baxter, David; Stieglitz, John; Mager, Edward; Hoenig, Ronald; Benetti, Daniel; Grosell, Martin; Oris, James; Roberts, Aaron

    2016-02-16

    The 2010 Deepwater Horizon oil spill resulted in the accidental release of millions barrels of crude oil into the Gulf of Mexico. Photoinduced toxicity following coexposure to ultraviolet (UV) radiation is one mechanism by which polycyclic aromatic hydrocarbons (PAHs) from oil spills may exert toxicity. Mahi-mahi (Coryphaena hippurus), an important fishery resource, have positively buoyant, transparent eggs. These characteristics may result in mahi-mahi embryos being at particular risk from photoinduced toxicity. The goal of this study was to determine whether exposure to ultraviolet radiation as natural sunlight enhances the toxicity of crude oil to embryonic mahi-mahi. Mahi-mahi embryos were exposed to several dilutions of water accommodated fractions (WAF) from slick oil collected during the 2010 spill and gradations of natural sunlight in a fully factorial design. Here, we report that coexposure to natural sunlight and WAF significantly reduced percent hatch in mahi-mahi embryos. Effect concentrations of PAH in WAF were within the range of surface PAH concentrations reported in the Gulf of Mexico during the Deepwater Horizon spill. These data suggest that laboratory toxicity tests that do not include UV may underestimate the toxicity of oil spills to early lifestage fish species. PMID:26784438

  14. Polyaniline nanofibers: acute toxicity and teratogenic effect on Rhinella arenarum embryos.

    PubMed

    Yslas, Edith I; Ibarra, Luis E; Peralta, Damián O; Barbero, César A; Rivarola, Viviana A; Bertuzzi, Mabel L

    2012-06-01

    The fate and effect of nanomaterials in the environment is of paramount importance towards the technological application of the materials. This work shows the ecotoxicological potential of polyaniline (PANI) nanofibers in the larvae Rhinella arenarum by means of AMPHITOX test. Acute toxicity of PANI nanofibers towards embryos of the common South American toad R. arenarum (Anura: bufonidae) was evaluated in the premetamorphosis (stage 25) larvae. The exposure of R. arenarum larvae to at dose of 150, 250 and 400 mg L(-1) resulted in 100% viability within 96 h exposure. The embryos at 2-4 blastomers stage (early life stage teratogenic test) revealed that embryos were not killed and no teratogenic effects were observed when embryos were incubated with PANI nanofibers (150 and 250 mg L(-1)), while only a growth retardation of embryos was induced at levels of 250 mg PANI nanofibers L(-1). On the other hand, at 400 mg L(-1) concentration, a reduction in the body length of larvae and tail malformation was observed. This results suggest that a concentration-dependent toxicity is operative, typified by phenotypes that had abnormal body axes. The presence of PANI nanofibers in gut contents and its excretion by larval stages of R. arenarum was confirmed by UV-visible spectroscopy. PMID:22386461

  15. Rapid aquatic toxicity assay using incorporation of tritiated-thymidine into sea urchin, Arbacia punctulata, embryo: evaluation of toxicant exposure procedures

    SciTech Connect

    Nacci, D.E.; Jackim, E.

    1985-01-01

    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 toxicant exposure procedures using the Arbacia embryo thymidine incorporation test. Toxicant exposure began before, at the time of, or after fertilization and continued for 4 h following fertilization. In addition to the eight organic chemicals tested for comparison to acute toxicity values for other species, several chemicals with embryotoxic potentials (tumor promoters and teratogens) were tested to determine differential sensitivities of exposed life-stages: unfertilized egg, fertilization, and early embryo. EC50 values for any one substance were not significantly changed by exposure modification. Toxicity values for exposures that included fertilization as well as early embryo growth were at least as sensitive as post-fertilization exposure values for all compounds tested except one. Because of technical ease and potential sensitivity, toxicant exposure that includes fertilization as well as early embryo growth (but not unfertilized egg exposure) is recommended for future testing.

  16. Mouse embryo quality control for toxicity determination in the Norfolk in vitro fertilization program.

    PubMed

    McDowell, J S; Swanson, R J; Maloney, M; Veeck, L

    1988-06-01

    Ongoing quality control is necessary as part of the maintenance and improvement of a successful human in vitro fertilization (IVF) program. Using a mouse quality-control culture system, several instrument preparation protocols were reevaluated to determine their efficiency in the control or elimination of potential toxicity. Dilute concentrations of urine and endometrial fluid were also tested. Medium rinsed through laparoscope and aspiration needles failed to support embryo development. This effect was reversed in needles that were pretreated with rinses of Dulbecco's phosphate-buffered saline. Endometrial fluid demonstrated no obvious toxic effect, but urine-exposed embryos arrested in the two-cell state. The importance of periodic evaluation of materials and their pretreatment before use in in vitro fertilization of human oocytes is essential to ensure control of potentially toxic substances.

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

    SciTech Connect

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

    1993-01-01

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

  18. 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

    Hull, C.G.

    1993-01-01

    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.

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

    PubMed

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

    2014-02-01

    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.

  20. Differences in toxicity of anionic and cationic PAMAM and PPI dendrimers in zebrafish embryos and cancer cell lines.

    PubMed

    Bodewein, Lambert; Schmelter, Frank; Di Fiore, Stefano; Hollert, Henner; Fischer, Rainer; Fenske, Martina

    2016-08-15

    Dendrimers are an emerging class of polymeric nanoparticles with beneficial biomedical applications like early diagnostics, in vitro gene transfection or controlled drug delivery. However, the potential toxic impact of exposure on human health or the environment is often inadequately defined. Thus, polyamidoamine (PAMAM) dendrimers of generations G3.0, 3.5, 4.0, 4.5 and 5.0 and polypropylenimine (PPI) dendrimers G3.0, 4.0 and 5.0 were tested in zebrafish embryos for 96h and human cancer cell lines for 24h, to assess and compare developmental in vivo toxicity with cytotoxicity. The zebrafish embryo toxicity of cationic PAMAM and PPI dendrimers increased over time, with EC50 values ranging from 0.16 to just below 1.7μM at 24 and 48hpf. The predominant effects were mortality, plus reduced heartbeat and blood circulation for PPI dendrimers. Apoptosis in the embryos increased in line with the general toxicity concentration-dependently. Hatch and dechorionation of the embryos increased the toxicity, suggesting a protective role of the chorion. Lower generation dendrimers were more toxic in the embryos whereas the toxicity in the HepG2 and DU145 cell lines increased with increasing generation of cationic PAMAMs and PPI dendrimers. HepG2 were less sensitive than DU145 cells, with IC50 values≥402μM (PAMAMs) and ≤240μM (PPIs) for HepG2 and ≤13.24μM (PAMAMs) and ≤12.84μM (PPIs) for DU145. Neither in fish embryos nor cells toxicity thresholds were determinable for anionic PAMAM G3.5 and G4.5. The study demonstrated that the cytotoxicity underestimated the in-vivo toxicity of the dendrimers in the fish embryos. PMID:27288734

  1. Differences in toxicity of anionic and cationic PAMAM and PPI dendrimers in zebrafish embryos and cancer cell lines.

    PubMed

    Bodewein, Lambert; Schmelter, Frank; Di Fiore, Stefano; Hollert, Henner; Fischer, Rainer; Fenske, Martina

    2016-08-15

    Dendrimers are an emerging class of polymeric nanoparticles with beneficial biomedical applications like early diagnostics, in vitro gene transfection or controlled drug delivery. However, the potential toxic impact of exposure on human health or the environment is often inadequately defined. Thus, polyamidoamine (PAMAM) dendrimers of generations G3.0, 3.5, 4.0, 4.5 and 5.0 and polypropylenimine (PPI) dendrimers G3.0, 4.0 and 5.0 were tested in zebrafish embryos for 96h and human cancer cell lines for 24h, to assess and compare developmental in vivo toxicity with cytotoxicity. The zebrafish embryo toxicity of cationic PAMAM and PPI dendrimers increased over time, with EC50 values ranging from 0.16 to just below 1.7μM at 24 and 48hpf. The predominant effects were mortality, plus reduced heartbeat and blood circulation for PPI dendrimers. Apoptosis in the embryos increased in line with the general toxicity concentration-dependently. Hatch and dechorionation of the embryos increased the toxicity, suggesting a protective role of the chorion. Lower generation dendrimers were more toxic in the embryos whereas the toxicity in the HepG2 and DU145 cell lines increased with increasing generation of cationic PAMAMs and PPI dendrimers. HepG2 were less sensitive than DU145 cells, with IC50 values≥402μM (PAMAMs) and ≤240μM (PPIs) for HepG2 and ≤13.24μM (PAMAMs) and ≤12.84μM (PPIs) for DU145. Neither in fish embryos nor cells toxicity thresholds were determinable for anionic PAMAM G3.5 and G4.5. The study demonstrated that the cytotoxicity underestimated the in-vivo toxicity of the dendrimers in the fish embryos.

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

    SciTech Connect

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

    2008-07-01

    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 reduced after the embryos were exposed to 1, 3 and 5 mg/L PFOS until 132 hpf. The fry displayed gross developmental malformations, including epiboly deformities, hypopigmentation, yolk sac edema, tail and heart malformations and spinal curvature upon exposure to PFOS concentrations of 1 mg/L or greater. Growth (body length) was significantly reduced in the 3 and 5 mg/L PFOS-treated groups. To test whether developmental malformation was mediated via apoptosis, flow cytometry analysis of DNA content, acridine orange staining and TUNEL assay was used. These techniques indicated that more apoptotic cells were present in the PFOS-treated embryos than in the control embryos. Certain genes related to cell apoptosis, p53 and Bax, were both significantly up-regulated upon exposure to all the concentrations tested. In addition, we investigated the effects of PFOS on marker genes related to early thyroid development (hhex and pax8) and genes regulating the balance of androgens and estrogens (cyp19a and cyp19b). For thyroid development, the expression of hhex was significantly up-regulated at all concentrations tested, whereas pax8 expression was significantly up-regulated only upon exposure to lower concentrations of PFOS (0.1, 0.5, 1 mg/L). The expression of cyp19a and of cyp19b was significantly down-regulated at all exposure concentrations. The overall results indicated that zebrafish embryos constitute a reliable model for testing the developmental toxicity of PFOS, and the gene expression patterns in the embryos were able to reveal some potential

  3. The developmental toxicity of three carrier solvents using embryos of the grass shrimp, Palaemonetes pugio

    SciTech Connect

    Rayburn, J.R.; Fisher, W.S.

    1995-12-31

    The embryos of the grass shrimp (Palaemonetes pugio) have shown sensitivity to the water-soluble fraction of Number 2 fuel oil which indicates this test may be ideal for use as an estuarine developmental toxicity test. Many chemicals that require testing of this nature are insoluble in water. To determine the possible use of carrier solvents in the grass shrimp bioassays, detailed concentration-response curves for each solvent were performed using two test methods. LC50 values for each method were obtained. The first test was a 4-day assay that included the time of hatch, a critical life stage of these embryos. The second test was a 12-d assay which included development from tissue cap stage embryos through 2 days post hatch. The average 4-day LC50s for ETOH, DMSO and acetone were 12.07, 22.57, and 6.80 g/L, respectively. The average 12-day LC50s for ETOH, DMSO and Acetone were 3.63, 12.33 and 6.94 g/L, respectively. The coefficients of variation of each test were always less than 25.2%. Eye malformations were observed with embryos exposed to ETOH, while embryos exposed to DMSO and acetone showed very little embryo malformation. One experiment showed abnormal development of the last abdominal segment. Based on the concentration-response curves, the maximum allowable limit of ETOH, DMSO and acetone to be used as a carrier should be 1, 6, and 4 g/L, respectively.

  4. Toxicity Estimation Software Tool (TEST)

    EPA Science Inventory

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

  5. 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

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

    2012-09-01

    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.

  6. Nickel and Copper Toxicity to Embryos of the Long-Spined Sea Urchin, Diadema savignyi.

    PubMed

    Rosen, G; Rivera-Duarte, I; Colvin, M A; Dolecal, R E; Raymundo, L J; Earley, P J

    2015-07-01

    The sensitivity of long-spined sea urchins (Diadema savignyi) collected from Guam (Northern Marianas Islands), USA, to nickel and copper in seawater was explored using 48-h embryo-larval development toxicity tests. The median effective concentrations (EC50) averaged 94 µg L(-1) for nickel, and 19 µg L(-1) from a single exposure to copper, and suggest relatively high sensitivity of this species to nickel compared with other sea urchin genera, but similar sensitivity to copper. Ambient nickel and copper concentrations concurrently sampled from 16 near-shore locations around Guam were one to two orders of magnitude lower than those that would be expected to result in adverse effects to D. savignyi embryos. Although nationally recommended chronic ambient water quality criteria, currently 8.2 and 3.1 µg L(-1) for nickel and copper, respectively, were not exceeded, recently derived qualifying toxicity data should be considered for updating these criteria to ensure protectiveness of sensitive tropical species.

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

    PubMed

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

    2014-04-01

    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. PMID:24375845

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

    PubMed

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

    2014-04-01

    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.

  9. Embryo toxicity of pesticides and heavy metals to the ramshorn snail, Marisa cornuarietis (Prosobranchia).

    PubMed

    Sawasdee, Banthita; Köhler, Heinz-R

    2009-06-01

    An invertebrate embryo toxicity test with the ampullariid snail, Marisacornuarietis, to assess the toxicity of pesticides and heavy metals recently was established. Snail embryos were treated with atrazine (100, 1000, 10000, and 30000 microg/L), imidacloprid (10000, 25000, and 50000 microg/L), Ni(2+) (0.1, 1, 10, and 100 microg/L) or Zn(2+) (100, 200, 500, 1000, 2000, and 5000 microg/L). The effect of these substances was examined by monitoring the following endpoints: mortality, formation of tentacles and eyes, heart rate, hatching, and weight after hatching. Effects in term of a significant delay on the formation of both tentacles and eyes were found after treatment with 100 microg/L Ni(2+) or 200 microg/L Zn(2+). The heart rate was shown to significantly decrease at 25000 microg/L imidacloprid or 1000 microg/L Zn(2+). At 100 microg/L atrazine, 10 microg/L Ni(2+), or 1000 microg/L Zn(2+) a significant delay in hatching became visible. No significant mortality was observed for the tested concentrations of atrazine, imidacloprid, or Ni(2+), while 5000 microg/L Zn(2+) resulted in 100% mortality after 10d. The weight of freshly hatched individuals remained unaffected in all treatments. On the basis of the lowest observed effect concentrations (LOECs) recorded, we could show the M.cornuarietis embryo toxicity test (MariETT) to react up to three orders of magnitude more sensitive (for metals) and at least one order of magnitude more sensitive (for the tested organics) than the established Danio rerio embryo test.

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

    PubMed

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

    2013-05-01

    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.

  11. Screening the Toxicity of Selected Personal Care Products Using Embryo Bioassays: 4-MBC, Propylparaben and Triclocarban

    PubMed Central

    Torres, Tiago; Cunha, Isabel; Martins, Rosário; Santos, Miguel M.

    2016-01-01

    Recently, several emerging pollutants, including Personal Care Products (PCPs), have been detected in aquatic ecosystems, in the ng/L or µg/L range. Available toxicological data is limited, and, for certain PCPs, evidence indicates a potential risk for the environment. Hence, there is an urgent need to gather ecotoxicological data on PCPs as a proxy to improve risk assessment. Here, the toxicity of three different PCPs (4-Methylbenzylidene Camphor (4-MBC), propylparaben and triclocarban) was tested using embryo bioassays with Danio rerio (zebrafish) and Paracentrotus lividus (sea urchin). The No Observed Effect Concentration (NOEC) for triclocarban was 0.256 µg/L for sea urchin and 100 µg/L for zebrafish, whereas NOEC for 4-MBC was 0.32 µg/L for sea urchin and 50 µg/L for zebrafish. Both PCPs impacted embryo development at environmentally relevant concentrations. In comparison with triclocarban and 4-MBC, propylparaben was less toxic for both sea urchin (NOEC = 160 µg/L) and zebrafish (NOEC = 1000 µg/L). Overall, this study further demonstrates the sensitivity of embryo bioassays as a high-throughput approach for testing the toxicity of emerging pollutants. PMID:27775672

  12. Acute embryo toxicity and teratogenicity of three potential biofuels also used as flavor or solvent.

    PubMed

    Bluhm, Kerstin; Seiler, Thomas-Benjamin; Anders, Nico; Klankermayer, Jürgen; Schaeffer, Andreas; Hollert, Henner

    2016-10-01

    The demand for biofuels increases due to concerns regarding greenhouse gas emissions and depletion of fossil oil reserves. Many substances identified as potential biofuels are solvents or already used as flavors or fragrances. Although humans and the environment may be readily exposed little is known regarding their (eco)toxicological effects. In this study, the three potential biofuels ethyl levulinate (EL), 2-methyltetrahydrofuran (2-MTHF) and 2-methylfuran (2-MF) were investigated for their acute embryo toxicity and teratogenicity using the fish embryo toxicity (FET) test to identify unknown hazard potentials and to allow focusing further research on substances with low toxic potentials. In addition, two fossil fuels (diesel and gasoline) and an established biofuel (rapeseed oil methyl ester) were investigated as references. The FET test is widely accepted and used in (eco)toxicology. It was performed using the zebrafish Danio rerio, a model organism useful for the prediction of human teratogenicity. Testing revealed a higher acute toxicity for EL (LC50: 83mg/L) compared to 2-MTHF (LC50: 2980mg/L), 2-MF (LC50: 405mg/L) and water accommodated fractions of the reference fuels including gasoline (LC50: 244mg DOC/L). In addition, EL caused a statistically significant effect on head development resulting in elevated head lengths in zebrafish embryos. Results for EL reduce its likelihood of use as a biofuel since other substances with a lower toxic potential are available. The FET test applied at an early stage of development might be a useful tool to avoid further time and money requiring steps regarding research on unfavorable biofuels.

  13. Acute embryo toxicity and teratogenicity of three potential biofuels also used as flavor or solvent.

    PubMed

    Bluhm, Kerstin; Seiler, Thomas-Benjamin; Anders, Nico; Klankermayer, Jürgen; Schaeffer, Andreas; Hollert, Henner

    2016-10-01

    The demand for biofuels increases due to concerns regarding greenhouse gas emissions and depletion of fossil oil reserves. Many substances identified as potential biofuels are solvents or already used as flavors or fragrances. Although humans and the environment may be readily exposed little is known regarding their (eco)toxicological effects. In this study, the three potential biofuels ethyl levulinate (EL), 2-methyltetrahydrofuran (2-MTHF) and 2-methylfuran (2-MF) were investigated for their acute embryo toxicity and teratogenicity using the fish embryo toxicity (FET) test to identify unknown hazard potentials and to allow focusing further research on substances with low toxic potentials. In addition, two fossil fuels (diesel and gasoline) and an established biofuel (rapeseed oil methyl ester) were investigated as references. The FET test is widely accepted and used in (eco)toxicology. It was performed using the zebrafish Danio rerio, a model organism useful for the prediction of human teratogenicity. Testing revealed a higher acute toxicity for EL (LC50: 83mg/L) compared to 2-MTHF (LC50: 2980mg/L), 2-MF (LC50: 405mg/L) and water accommodated fractions of the reference fuels including gasoline (LC50: 244mg DOC/L). In addition, EL caused a statistically significant effect on head development resulting in elevated head lengths in zebrafish embryos. Results for EL reduce its likelihood of use as a biofuel since other substances with a lower toxic potential are available. The FET test applied at an early stage of development might be a useful tool to avoid further time and money requiring steps regarding research on unfavorable biofuels. PMID:27243931

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

    PubMed

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

    2002-01-01

    By-products from a bauxite manufacturing plant located in Seydişehir, 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 Seydişehir 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 Seydişehir plant compared with other bauxite manufacturing plants suggest a possible variable toxicity as related to bauxite ore composition and/or manufacturing processes.

  15. Unexpected interaction with dispersed crude oil droplets drives severe toxicity in Atlantic haddock embryos.

    PubMed

    Sørhus, Elin; Edvardsen, Rolf B; Karlsen, Ørjan; Nordtug, Trond; van der Meeren, Terje; Thorsen, Anders; Harman, Christopher; Jentoft, Sissel; Meier, Sonnich

    2015-01-01

    The toxicity resulting from exposure to oil droplets in marine fish embryos and larvae is still subject for debate. The most detailed studies have investigated the effects of water-dissolved components of crude oil in water accommodated fractions (WAFs) that lack bulk oil droplets. Although exposure to dissolved petroleum compounds alone is sufficient to cause the characteristic developmental toxicity of crude oil, few studies have addressed whether physical interaction with oil micro-droplets are a relevant exposure pathway for open water marine speices. Here we used controlled delivery of mechanically dispersed crude oil to expose pelagic embryos and larvae of a marine teleost, the Atlantic haddock (Melanogrammus aeglefinus). Haddock embryos were exposed continuously to two different concentrations of dispersed crude oil, high and low, or in pulses. By 24 hours of exposure, micro-droplets of oil were observed adhering and accumulating on the chorion, accompanied by highly elevated levels of cyp1a, a biomarker for exposure to aromatic hydrocarbons. Embryos from all treatment groups showed abnormalities representative of crude oil cardiotoxicity at hatch (5 days of exposure), such as pericardial and yolk sac edema. Compared to other species, the frequency and severity of toxic effects was higher than expected for the waterborne PAH concentrations (e.g., 100% of larvae had edema at the low treatment). These findings suggest an enhanced tissue uptake of PAHs and/or other petroleum compounds from attached oil droplets. These studies highlight a novel property of haddock embryos that leads to greater than expected impact from dispersed crude oil. Given the very limited number of marine species tested in similar exposures, the likelihood of other species with similar properties could be high. This unanticipated result therefore has implications for assessing the ecological impacts of oil spills and the use of methods for dispersing oil in the open sea.

  16. Unexpected Interaction with Dispersed Crude Oil Droplets Drives Severe Toxicity in Atlantic Haddock Embryos

    PubMed Central

    Sørhus, Elin; Edvardsen, Rolf B.; Karlsen, Ørjan; Nordtug, Trond; van der Meeren, Terje; Thorsen, Anders; Harman, Christopher; Jentoft, Sissel; Meier, Sonnich

    2015-01-01

    The toxicity resulting from exposure to oil droplets in marine fish embryos and larvae is still subject for debate. The most detailed studies have investigated the effects of water-dissolved components of crude oil in water accommodated fractions (WAFs) that lack bulk oil droplets. Although exposure to dissolved petroleum compounds alone is sufficient to cause the characteristic developmental toxicity of crude oil, few studies have addressed whether physical interaction with oil micro-droplets are a relevant exposure pathway for open water marine speices. Here we used controlled delivery of mechanically dispersed crude oil to expose pelagic embryos and larvae of a marine teleost, the Atlantic haddock (Melanogrammus aeglefinus). Haddock embryos were exposed continuously to two different concentrations of dispersed crude oil, high and low, or in pulses. By 24 hours of exposure, micro-droplets of oil were observed adhering and accumulating on the chorion, accompanied by highly elevated levels of cyp1a, a biomarker for exposure to aromatic hydrocarbons. Embryos from all treatment groups showed abnormalities representative of crude oil cardiotoxicity at hatch (5 days of exposure), such as pericardial and yolk sac edema. Compared to other species, the frequency and severity of toxic effects was higher than expected for the waterborne PAH concentrations (e.g., 100% of larvae had edema at the low treatment). These findings suggest an enhanced tissue uptake of PAHs and/or other petroleum compounds from attached oil droplets. These studies highlight a novel property of haddock embryos that leads to greater than expected impact from dispersed crude oil. Given the very limited number of marine species tested in similar exposures, the likelihood of other species with similar properties could be high. This unanticipated result therefore has implications for assessing the ecological impacts of oil spills and the use of methods for dispersing oil in the open sea. PMID:25923774

  17. Differential developmental toxicity of naphthoic acid isomers in medaka (Oryzias latipes) embryos

    PubMed Central

    Carney, Michael W.; Erwin, Kyle; Hardman, Ron; Yuen, Bonny; Volz, David C.; Hinton, David E.; Kullman, Seth W.

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread persistent pollutants that readily undergo biotic and abiotic conversion to numerous transformation products in rivers, lakes and estuarine sediments. Here we characterize the developmental toxicity of four PAH transformation products each structural isomers of hydroxynaphthoic acid: 1H2NA, 2H1NA, 2H3NA, and 6H2NA. Medaka fish (Oryzias latipes) embryos and eleutheroembryos were used to determine toxicity. A 96-well micro-plate format was used to establish a robust, statistically significant platform for assessment of early life stages. Individual naphthoic acid isomers demonstrated a rank order of toxicity with 1H2NA > 2H1NA > 2H3NA > 6H2NA being more toxic. Abnormalities of circulatory system were most pronounced including pericardial edema and tube heart. To determine if HNA isomers were AhR ligands, spatial-temporal expression and activity of CYP1A was measured via in vivo EROD assessments. qPCR measurement of CYP1A induction proved different between isomers dosed at respective concentrations affecting 50% of exposed individuals (EC50s). In vitro, all ANH isomers transactivated mouse AhR using a medaka CYP1A promoter specific reporter assay. Circulatory abnormalities followed P450 induction and response was consistent with PAH toxicity. A 96-well micro-plates proved suitable as exposure chambers and provided statistically sound evaluations as well as efficient toxicity screens. Our results demonstrate the use of medaka embryos for toxicity analysis thereby achieving REACH objectives for the reduction of adult animal testing in toxicity evaluations. PMID:18433798

  18. Toxicity of seabird guano to sea urchin embryos and interaction with Cu and Pb.

    PubMed

    Rial, Diego; Santos-Echeandía, Juan; Álvarez-Salgado, Xosé Antón; Jordi, Antoni; Tovar-Sánchez, Antonio; Bellas, Juan

    2016-02-01

    Guano is an important source of marine-derived nutrients to seabird nesting areas. Seabirds usually present high levels of metals and other contaminants because the bioaccumulation processes and biotic depositions can increase the concentration of pollutants in the receiving environments. The objectives of this study were to investigate: the toxicity of seabird guano and the joint toxicity of guano, Cu and Pb by using the sea urchin embryo-larval bioassay. In a first experiment, aqueous extracts of guano were prepared at two loading rates (0.462 and 1.952 g L(-1)) and toxicity to sea-urchin embryos was tested. Toxicity was low and not dependent of the load of guano used (EC50 0.42 ± 0.03 g L(-1)). Trace metal concentrations were also low either in guano or in aqueous extracts of guano and the toxicity of extracts were apparently related to dissolved organic matter. In a second experiment, the toxicity of Cu-Pb mixtures in artificial seawater and in extracts of guano (at two loadings: 0.015 and 0.073 g L(-1)), was tested. According to individual fittings, Cu added to extracts of guano showed less toxicity than when dissolved in artificial seawater. The response surfaces obtained for mixtures of Cu and Pb in artificial seawater, and in 0.015 g L(-1) and 0.073 g L(-1) of guano, were better described by Independent Action model adapted to describe antagonism, than by the other proposed models. This implied accepting that EC50 for Cu and Pb increased with the load of guano and with a greater interaction for Cu than for Pb.

  19. Toxicity of seabird guano to sea urchin embryos and interaction with Cu and Pb.

    PubMed

    Rial, Diego; Santos-Echeandía, Juan; Álvarez-Salgado, Xosé Antón; Jordi, Antoni; Tovar-Sánchez, Antonio; Bellas, Juan

    2016-02-01

    Guano is an important source of marine-derived nutrients to seabird nesting areas. Seabirds usually present high levels of metals and other contaminants because the bioaccumulation processes and biotic depositions can increase the concentration of pollutants in the receiving environments. The objectives of this study were to investigate: the toxicity of seabird guano and the joint toxicity of guano, Cu and Pb by using the sea urchin embryo-larval bioassay. In a first experiment, aqueous extracts of guano were prepared at two loading rates (0.462 and 1.952 g L(-1)) and toxicity to sea-urchin embryos was tested. Toxicity was low and not dependent of the load of guano used (EC50 0.42 ± 0.03 g L(-1)). Trace metal concentrations were also low either in guano or in aqueous extracts of guano and the toxicity of extracts were apparently related to dissolved organic matter. In a second experiment, the toxicity of Cu-Pb mixtures in artificial seawater and in extracts of guano (at two loadings: 0.015 and 0.073 g L(-1)), was tested. According to individual fittings, Cu added to extracts of guano showed less toxicity than when dissolved in artificial seawater. The response surfaces obtained for mixtures of Cu and Pb in artificial seawater, and in 0.015 g L(-1) and 0.073 g L(-1) of guano, were better described by Independent Action model adapted to describe antagonism, than by the other proposed models. This implied accepting that EC50 for Cu and Pb increased with the load of guano and with a greater interaction for Cu than for Pb. PMID:26692516

  20. Marine toxicity tests development with a New Zealand echinoid

    SciTech Connect

    Nipper, M.G.; Roper, D.S.; Martin, M.L.; Williams, E.K.

    1995-12-31

    The generally low levels of contamination around New Zealand lead to the search for a sensitive toxicity test, which could be used to screen effluent and to detect contaminant effects in coastal waters and sediments. Echinoid early life stage tests were considered ideal candidates. However, the adaptation of international toxicity test methods to indigenous species has not been straightforward or troublefree! The echinoid Fellaster zelandiae was selected because it is abundant around New Zealand and is fertile year round. Fertilization tests showed that gamete density, rather than sperm/egg ratio, was a crucial factor for successful control fertilization rates. This method, however, presented several problems related to (1) temporal variability in the quality of sperm batches, (2) rapid reduction of egg quality and viability after spawning, and (3) highly variable sensitivity in reference toxicant tests. Embryo tests were more reliable, with good control results (> 80% normal embryos) and consistent sensitivity to a reference toxicant, zinc sulfate. EC{sub 50} values averaged 0.06 mg Zn/L, comparable to the sensitivity of echinoid species used elsewhere. Brine prepared by freezing seawater was suitable for adjusting the salinity of effluents, with more than 90% normal embryos developing in brine diluted with UV-treated deionized water as a test-control. The assessment of the embryo development test as a tool for screening sediment toxicity (using sediment pore water), is presently underway, concurrently with growth and behavioral endpoint tests using indigenous amphipods and bivalves.

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

    PubMed

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

    2014-08-01

    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.

  2. Assessment of biocompatibility of 3D printed photopolymers using zebrafish embryo toxicity assays.

    PubMed

    Macdonald, N P; Zhu, F; Hall, C J; Reboud, J; Crosier, P S; Patton, E E; Wlodkowic, D; Cooper, J M

    2016-01-21

    3D printing has emerged as a rapid and cost-efficient manufacturing technique to enable the fabrication of bespoke, complex prototypes. If the technology is to have a significant impact in biomedical applications, such as drug discovery and molecular diagnostics, the devices produced must be biologically compatible to enable their use with established reference assays and protocols. In this work we demonstrate that we can adapt the Fish Embryo Test (FET) as a new method to quantify the toxicity of 3D printed microfluidic devices. We assessed the biocompatibility of four commercially available 3D printing polymers (VisiJetCrystal EX200, Watershed 11122XC, Fototec SLA 7150 Clear and ABSplus P-430), through the observation of key developmental markers in the developing zebrafish embryos. Results show all of the photopolymers to be highly toxic to the embryos, resulting in fatality, although we do demonstrate that post-printing treatment of Fototec 7150 makes it suitable for zebrafish culture within the FET. PMID:26646354

  3. Drosophila Embryos as Model to Assess Cellular and Developmental Toxicity of Multi-Walled Carbon Nanotubes (MWCNT) in Living Organisms

    PubMed Central

    Liu, Boyin; Campo, Eva M.; Bossing, Torsten

    2014-01-01

    Different toxicity tests for carbon nanotubes (CNT) have been developed to assess their impact on human health and on aquatic and terrestrial animal and plant life. We present a new model, the fruit fly Drosophila embryo offering the opportunity for rapid, inexpensive and detailed analysis of CNTs toxicity during embryonic development. We show that injected DiI labelled multi-walled carbon nanotubes (MWCNTs) become incorporated into cells in early Drosophila embryos, allowing the study of the consequences of cellular uptake of CNTs on cell communication, tissue and organ formation in living embryos. Fluorescently labelled subcellular structures showed that MWCNTs remained cytoplasmic and were excluded from the nucleus. Analysis of developing ectodermal and neural stem cells in MWCNTs injected embryos revealed normal division patterns and differentiation capacity. However, an increase in cell death of ectodermal but not of neural stem cells was observed, indicating stem cell-specific vulnerability to MWCNT exposure. The ease of CNT embryo injections, the possibility of detailed morphological and genomic analysis and the low costs make Drosophila embryos a system of choice to assess potential developmental and cellular effects of CNTs and test their use in future CNT based new therapies including drug delivery. PMID:24558411

  4. VIRTUAL EMBRYO: SYSTEMS MODELING IN DEVELOPMENTAL TOXICITY - Symposium: SOT 2012

    EPA Science Inventory

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to in vitro profiling of chemical compounds for biological activity and potential toxicity. Chemical profiling in ToxCast covered 965 drugs-chemicals in over 500 diverse assays testing...

  5. Synergistic interaction of glycoalkaloids alpha-chaconine and alpha-solanine on developmental toxicity in Xenopus embryos.

    PubMed

    Rayburn, J R; Friedman, M; Bantle, J A

    1995-12-01

    The embryo toxicities of two major potato glycoalkaloids, alpha-chaconine and alpha-solanine, were examined individually and in mixtures using the frog embryo teratogenesis assay-Xenopus. Calculations of toxic units (TUs) were used to assess possible antagonism, synergism or response addition of several mixtures ranging from approximately 3:1 to 1:20 TUs of alpha-chaconine to alpha-solanine. Some combinations exhibited strong synergism in the following measures of developmental toxicity: (a) 96-hr LC50, defined as the median concentration causing 50% embryo lethality; (b) 96-hr EC50 (malformation), defined as the concentration causing 50% malformation of the surviving embryos; and (c) teratogenic index which is equal to LC50/EC50 (malformation). The results indicated that each of the mixtures caused synergistic mortality or malformation. Furthermore, these studies suggested that the synergism observed for a specific mixture cannot be used to predict possible synergism of other mixtures with different ratios of the two glycoalkaloids; toxicities observed for individual glycoalkaloids may not be able to predict toxicities of mixtures; and specific combinations found in different potato varieties need to be tested to assess the safety of a particular cultivar.

  6. Toxic effects of zinc on the development, growth, and survival of red sea bream Pagrus major embryos and larvae.

    PubMed

    Huang, Wei; Cao, Liang; Shan, Xiujuan; Xiao, Zhizhong; Wang, Qiyao; Dou, Shuozeng

    2010-01-01

    This study investigated the zinc toxicity to red sea bream Pagrus major embryos and larvae at 18 +/- 1 degrees C (33 +/- 1 per thousand in salinity) under laboratory conditions. The acute toxicity tests indicated that zinc 48-h LC50 to embryos and 96-h LC50 to larvae were 4.3 (3.3-6.3; 95% confidence limits) and 10.1 (9.0-11.4) mg l(-1), respectively, suggesting that embryos were more sensitive than larvae to zinc exposure. The subchronic toxicity test, in which embryos and larvae were continuously exposed to 0, 0.1, 0.3, 0.5, 0.7, 1.0, 1.5, 2.0, and 2.5 mg Zn2+ l(-1) solutions for 10 days, demonstrated that waterborne zinc had distinctly toxic effects on the development, growth, and survival of red sea bream embryos and larvae. Zinc exposure at concentrations > or = 0.5 mg l(-1) would lead to a low hatching rate (19-78%, vs. 98% in controls), high mortality (29-91%, vs. 10% in controls), and morphological abnormality (12-77%, vs. 0.3% in controls) in embryos and larvae, while it caused delay in time-to-hatch in embryos at concentrations > or = 1.0 mg l(-1). These four biological parameters were zinc concentration dependent and could be effective bioindicators for evaluating the toxicity of zinc to the early life stage of this fish. Heartbeats of embryos (9-13 beats 10 s(-1)) were relatively low and were not significantly influenced by zinc concentration, although they rose remarkably with elevated zinc concentration in larvae at the end of the test, particularly when it was > or = 1.0 mg l(-1) (36-38, vs. 31 beats 10 s(-1) in controls). The total length (LT) of the larvae at the end of the test was reduced by 12.2% and 15.6% in the 1.0 and 2.0 mg l(-1) solutions but did not vary significantly in other solutions in comparison with the controls. Heartbeat and LT were less sensitive to zinc exposure and might not be good biological parameters for determining the toxicity of zinc to the early life stage of red sea bream. PMID:19504147

  7. Developmental toxicity of three hexabromocyclododecane diastereoisomers in embryos of the marine medaka Oryzias melastigma.

    PubMed

    Hong, Haizheng; Shen, Rong; Liu, Wanxin; Li, Dongmei; Huang, Lingming; Shi, Dalin

    2015-12-15

    The composition of major hexabromocyclododecane (HBCD) diastereoisomers, i.e. α-, β-, and γ-HBCDs, in marine biota is different from that of the commercially available form (technical HBCD), which is used extensively for toxicological studies. To properly evaluate the impact of HBCDs, the embryos of Oryzias melastigma were used to examine the developmental toxicity of the individual diastereoisomers. Results showed that HBCD diastereoisomers at the environmentally realistic concentrations in the embryos induced malformation rate and heartbeat, and caused the appearance of apoptotic heart. In addition, α-, β-, and γ-HBCDs had similar potency to stimulate the generation of reactive oxygen species, consequently leading to apoptosis in O. melastigma embryos. The order of the developmental toxicity of α-, β-, and γ-HBCDs in O. melastigma embryos was different from that in zebrafish embryos studied previously, which highlighted the importance of using species from both fresh and salt water for toxicity assessment. PMID:26563546

  8. Toxicity of binary mixtures of oil fractions to sea urchin embryos.

    PubMed

    Rial, Diego; Vázquez, José A; Menduiña, Araceli; García, Ana M; González, M Pilar; Mirón, Jesús; Murado, Miguel A

    2013-12-15

    The assumption of additive toxicity for oil compounds is related to a narcotic mode of action. However, the joint toxicity of oil fractions has not been fully investigated. A fractionation of Maya crude oil into aliphatics, aromatics and polars was performed, fractions were dissolved in dimethyl sulfoxide (DMSO) and subsequently toxicity of single fractions and binary mixtures was assessed using the sea urchin embryo test. The descriptive ability of Concentration Addition (CA), Independent Action (IA) and modifications of both models for describing the joint toxicity of mixtures has also been evaluated. The hydrocarbon content extractable with dichloromethane of the fractions dissolved in DMSO was: 12.0 ± 1.8 mg mL(-1), 39.0 ± 0.5 mg mL(-1) and 20.5 ± 2.5 mg mL(-1) for aliphatics, aromatics and polars, respectively. The toxicity of the extracts in DMSO of the fractions as EC50 (μLL(-1)) was: aliphatics (165.8-242.3)toxicity of oil fractions. In addition, synergistic or antagonistic effects were not observed.

  9. Effects of environmental toxicants on development of a teleost embryo

    SciTech Connect

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

    1985-11-01

    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.

  10. Effects of photoinduced toxicity of fluoranthene on amphibian embryos and larvae

    SciTech Connect

    Hatch, A.C.; Burton, G.A. Jr.

    1998-09-01

    Embryos and newly hatched larvae of three amphibian species, the spotted salamander (Ambystoma maculatum), the northern leopard frog (Rana pipiens), and the African clawed frog (Xenopus laevis), were exposed to fluoranthene and ultraviolet (UV) light in two scenarios. Embryos were exposed in a laboratory setting from an early developmental stage through hatching under artificial UV light, and newly hatched larvae were exposed outdoors in varying sunlight intensity levels. Outdoor exposures indicated greater sensitivity in the toxic response than did laboratory exposures. In the laboratory, mortality and malformation of X. laevis were the most sensitive indicators of exposure. Xenopus laevis was also the most sensitive species tested to the effects of UV light alone. Hatching success of R. pipiens was monitored outdoors and was not a useful predictive endpoint in the determination of photoinduced toxicity; however, newly hatched larvae were sensitive to the effects of photoinduced toxicity. Amybstoma maculatum and X. laevis larvae were affected by low ({micro}g/L) concentrations of fluoranthene in sunlight. These findings suggest that low levels of polycyclic aromatic hydrocarbons could be acting synergistically with environmental factors such as UV light to place young amphibians at risk.

  11. Artifacts in ambient toxicity testing

    SciTech Connect

    Kszos, L.A.; Stewart, A.J.

    1992-01-01

    Short-term toxicity tests with fathead minnow (Pimephales promelas) larvae and Ceriodaphnia dubia can be used to estimate the acute or chronic toxicity of effluents or receiving water. The results of effluent toxicity tests may need to be interpreted differently from the results of ambient toxicity tests. In this paper we provide examples of common artifacts, which can cause either false positives or false negatives, that we have encountered when these tests are used in ambient assessments. The examples we provide are drawn from diverse effluent and ambient water toxicity tests conducted at the Oak Ridge National Laboratory from March, 1985 through November, 1991. Three types of artifacts which have been encountered when using these tests in ambient applications are explored here. One type involves unusual replicate-specific variance in survival of fathead minnow larvae. The second and third types of artifacts affect the C. dubia test and appear to be related to food availability.

  12. Artifacts in ambient toxicity testing

    SciTech Connect

    Kszos, L.A.; Stewart, A.J.

    1992-10-01

    Short-term toxicity tests with fathead minnow (Pimephales promelas) larvae and Ceriodaphnia dubia can be used to estimate the acute or chronic toxicity of effluents or receiving water. The results of effluent toxicity tests may need to be interpreted differently from the results of ambient toxicity tests. In this paper we provide examples of common artifacts, which can cause either false positives or false negatives, that we have encountered when these tests are used in ambient assessments. The examples we provide are drawn from diverse effluent and ambient water toxicity tests conducted at the Oak Ridge National Laboratory from March, 1985 through November, 1991. Three types of artifacts which have been encountered when using these tests in ambient applications are explored here. One type involves unusual replicate-specific variance in survival of fathead minnow larvae. The second and third types of artifacts affect the C. dubia test and appear to be related to food availability.

  13. DEVELOPMENTAL TOXICITY OF DI- AND TETRACHLOROETHANE AND DICHLOROPROPANE IN EMBRYO CULTURE

    EPA Science Inventory

    DEVELOPMENTAL TOXICITY OF DI- AND TETRACHLOROETHANE AND DICHLOROPROPANE IN EMBRYO CULTURE. JE Andrews, H Nichols, and ES Hunter. Reproductive Toxicology Division, NHEERL, USEPA, RTP, NC.

    Disinfection of drinking water with chlorine results in numerous chlorinated byprodu...

  14. Toxicity test method development in southeast Asia

    SciTech Connect

    McPherson, C.A.

    1995-12-31

    Use of aquatic toxicity tests is relatively new in southeast Asia. As part of the ASEAN-Canada Cooperative Programme on Marine Science -- Phase 2, which includes development of marine environmental criteria, a need for tropical toxicity data was identified. A step-wise approach was used for test method development (simple, acute tests and easily measured endpoints first, then more complex short-term chronic methods), for test specific selection (using species found throughout the region first, and then considering species with narrower geographic distribution), and for integration of quality assurance/quality control (QA/QC) practices into all laboratory activities. Development of test protocols specifically for tropical species included acute and chronic toxicity tests with marine fish, invertebrates and algae. Criteria for test species selection will be reviewed. Method development was based on procedures and endpoints already widely used in North America and Europe (e.g., 96-h LC50 with fish), but adapted for use with tropical species. For example, a bivalve larval development test can use the same endpoints but the duration is only 24 hours. Test method development included research on culture and holding procedures, determination of test conditions (e.g., duration, test containers), and identification of appropriate endpoints. Acute tests with fish and invertebrates were developed first. The next step was development of short-term chronic tests to measure phytoplankton growth, bivalve and echinoderm embryo or larval development, and larval fish growth. The number of species and types of tests was increased in a staged approach, as laboratories became better equipped and personnel gained practical experience. In most cases, method development coincided with training workshops to introduce the principles of toxicity testing.

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

    PubMed Central

    2012-01-01

    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. PMID:22546201

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

    PubMed

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

    2013-01-01

    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

  17. Evaluation of the toxicity and teratogenity of six commercial textile dyes using the frog embryo teratogenesis assay-Xenopus.

    PubMed

    Birhanli, Ayse; Ozmen, Murat

    2005-01-01

    Potential developmental toxicities of six different textile dyes were evaluated using the frog embryo teratogenesis assay-Xenopus (FETAX). Xenopus laevis embryos were exposed to astrazon red FBL, astrazon blue FGRL, remazol red RR, remazol turquoise blue G-A, cibacron red FN-3G, and cibacron blue FN-R from stage 8 to 11 for a 96-h exposure period in static renewal test conditions. A minimum of 17 concentration-response tests were performed with tested dyes, excluding a control group for each dye. Median lethal concentration (LC50), malformation (EC50), non observed adverse effect concentration (NOAEC), and lowest observed adverse effect concentration (LOAEC) were calculated. Also, teratogenic index (TI), minimum concentration to inhibit growth (MCIG), and MCIG/LC50 values were determined for each of the tested dyes. Characteristic abnormalities induced by a given test material were determined by the relationship between concentration and dye in the study. Results from these studies suggested that each tested dye is teratogenic for X. laevis embryos. The lowest LC50 was determined for astrazon red exposure corresponding to a value of 4.73 mg/L. The LC50 value was similar for this dye and astrazon blue; the highest TI was calculated for astrazon blue exposure. Tests with X. laevis indicated that each of the tested compounds possessed teratogenic potential with varying degrees of potency: astrazon blue FGRL > remazol turquoise blue G-A > astrazon red FBL > cibacron blue FN-R > cibacron red FN-3G > remazol red RR. Different types of malformations occurred in the embryos, depending on concentration and dye. From these results, we can suggest that astrazon blue is the most toxic compound, but that the others are also highly toxic and teratogenic substances for X. laevis embryos. Results of the study confirmed that the FETAX assay can be useful in an integrated biological hazard assesment for the preliminary screening of textile dye stuff.

  18. Three-dimensional printed millifluidic devices for zebrafish embryo tests.

    PubMed

    Zhu, Feng; Skommer, Joanna; Macdonald, Niall P; Friedrich, Timo; Kaslin, Jan; Wlodkowic, Donald

    2015-07-01

    Implementations of Lab-on-a-Chip technologies for in-situ analysis of small model organisms and embryos (both invertebrate and vertebrate) are attracting an increasing interest. A significant hurdle to widespread applications of microfluidic and millifluidic devices for in-situ analysis of small model organisms is the access to expensive clean room facilities and complex microfabrication technologies. Furthermore, these resources require significant investments and engineering know-how. For example, poly(dimethylsiloxane) soft lithography is still largely unattainable to the gross majority of biomedical laboratories willing to pursue development of chip-based platforms. They often turn instead to readily available but inferior classical solutions. We refer to this phenomenon as workshop-to-bench gap of bioengineering science. To tackle the above issues, we examined the capabilities of commercially available Multi-Jet Modelling (MJM) and Stereolithography (SLA) systems for low volume fabrication of optical-grade millifluidic devices designed for culture and biotests performed on millimetre-sized specimens such as zebrafish embryos. The selected 3D printing technologies spanned a range from affordable personal desktop systems to high-end professional printers. The main motivation of our work was to pave the way for off-the-shelf and user-friendly 3D printing methods in order to rapidly and inexpensively build optical-grade millifluidic devices for customized studies on small model organisms. Compared with other rapid prototyping technologies such as soft lithography and infrared laser micromachining in poly(methyl methacrylate), we demonstrate that selected SLA technologies can achieve user-friendly and rapid production of prototypes, superior feature reproduction quality, and comparable levels of optical transparency. A caution need to be, however, exercised as majority of tested SLA and MJM resins were found toxic and caused significant developmental abnormalities

  19. Three-dimensional printed millifluidic devices for zebrafish embryo tests.

    PubMed

    Zhu, Feng; Skommer, Joanna; Macdonald, Niall P; Friedrich, Timo; Kaslin, Jan; Wlodkowic, Donald

    2015-07-01

    Implementations of Lab-on-a-Chip technologies for in-situ analysis of small model organisms and embryos (both invertebrate and vertebrate) are attracting an increasing interest. A significant hurdle to widespread applications of microfluidic and millifluidic devices for in-situ analysis of small model organisms is the access to expensive clean room facilities and complex microfabrication technologies. Furthermore, these resources require significant investments and engineering know-how. For example, poly(dimethylsiloxane) soft lithography is still largely unattainable to the gross majority of biomedical laboratories willing to pursue development of chip-based platforms. They often turn instead to readily available but inferior classical solutions. We refer to this phenomenon as workshop-to-bench gap of bioengineering science. To tackle the above issues, we examined the capabilities of commercially available Multi-Jet Modelling (MJM) and Stereolithography (SLA) systems for low volume fabrication of optical-grade millifluidic devices designed for culture and biotests performed on millimetre-sized specimens such as zebrafish embryos. The selected 3D printing technologies spanned a range from affordable personal desktop systems to high-end professional printers. The main motivation of our work was to pave the way for off-the-shelf and user-friendly 3D printing methods in order to rapidly and inexpensively build optical-grade millifluidic devices for customized studies on small model organisms. Compared with other rapid prototyping technologies such as soft lithography and infrared laser micromachining in poly(methyl methacrylate), we demonstrate that selected SLA technologies can achieve user-friendly and rapid production of prototypes, superior feature reproduction quality, and comparable levels of optical transparency. A caution need to be, however, exercised as majority of tested SLA and MJM resins were found toxic and caused significant developmental abnormalities

  20. Three-dimensional printed millifluidic devices for zebrafish embryo tests

    PubMed Central

    Zhu, Feng; Skommer, Joanna; Macdonald, Niall P.; Friedrich, Timo; Kaslin, Jan; Wlodkowic, Donald

    2015-01-01

    Implementations of Lab-on-a-Chip technologies for in-situ analysis of small model organisms and embryos (both invertebrate and vertebrate) are attracting an increasing interest. A significant hurdle to widespread applications of microfluidic and millifluidic devices for in-situ analysis of small model organisms is the access to expensive clean room facilities and complex microfabrication technologies. Furthermore, these resources require significant investments and engineering know-how. For example, poly(dimethylsiloxane) soft lithography is still largely unattainable to the gross majority of biomedical laboratories willing to pursue development of chip-based platforms. They often turn instead to readily available but inferior classical solutions. We refer to this phenomenon as workshop-to-bench gap of bioengineering science. To tackle the above issues, we examined the capabilities of commercially available Multi-Jet Modelling (MJM) and Stereolithography (SLA) systems for low volume fabrication of optical-grade millifluidic devices designed for culture and biotests performed on millimetre-sized specimens such as zebrafish embryos. The selected 3D printing technologies spanned a range from affordable personal desktop systems to high-end professional printers. The main motivation of our work was to pave the way for off-the-shelf and user-friendly 3D printing methods in order to rapidly and inexpensively build optical-grade millifluidic devices for customized studies on small model organisms. Compared with other rapid prototyping technologies such as soft lithography and infrared laser micromachining in poly(methyl methacrylate), we demonstrate that selected SLA technologies can achieve user-friendly and rapid production of prototypes, superior feature reproduction quality, and comparable levels of optical transparency. A caution need to be, however, exercised as majority of tested SLA and MJM resins were found toxic and caused significant developmental abnormalities

  1. Differential toxicity of three PCB congeners in developing sea urchin embryos and implication of TEQ approach

    SciTech Connect

    Schweitzer, L.; Suffet, I.; Hose, J.; Bay, S.

    1995-12-31

    The relationship between body burden and toxicity of three individual PCB congeners in developing sea urchin embryos was investigated to evaluate the validity of current predictive models of PCB toxicity in an invertebrate system. The uptake and accumulation of radiolabeled PCB congeners from sea water was measured in the sea urchin embryo tissues and the relative toxicity determined. According to the toxic equivalents (TEQ) approach of assessing risk to mammals, congener 77, a nonortho-substituted congener, is predicted to be more toxic than the diortho-substituted congeners 47 and 153. Using a 72 hour embryo development assay, congener 47 was found to be at least four times as toxic as congener 77, with EC50s of 15.7 and > 72.5 mmol/kg, respectively. Congener 153, a hexachlorobiphenyl, was virtually nontoxic even at the highest dose used. Cytologic and cytogenetic anomalies were studied to find a possibly more sensitive endpoint and to suggest a mechanism of toxicity. The cytogenetic analysis revealed that the PCBs inhibited mitosis. At the highest doses, complete mitotic arrest was observed. Congener 77 was found to be at least two times more toxic than congener 153 but not as toxic as congener 47 using mitotic activity as the endpoint. Thus, the two endpoints of toxicity did not change the order in which the congeners are toxic, but established different EC50s. The relative toxicities of these congeners in this study contradict the structure-activity prediction of the mammalian-based TEQ approach.

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

    SciTech Connect

    Beiras, R.; His, E.; Seaman, M.N.L.

    1998-10-01

    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.

  3. 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...

  4. Nickel and Copper Toxicity to Embryos of the Long-Spined Sea Urchin, Diadema savignyi.

    PubMed

    Rosen, G; Rivera-Duarte, I; Colvin, M A; Dolecal, R E; Raymundo, L J; Earley, P J

    2015-07-01

    The sensitivity of long-spined sea urchins (Diadema savignyi) collected from Guam (Northern Marianas Islands), USA, to nickel and copper in seawater was explored using 48-h embryo-larval development toxicity tests. The median effective concentrations (EC50) averaged 94 µg L(-1) for nickel, and 19 µg L(-1) from a single exposure to copper, and suggest relatively high sensitivity of this species to nickel compared with other sea urchin genera, but similar sensitivity to copper. Ambient nickel and copper concentrations concurrently sampled from 16 near-shore locations around Guam were one to two orders of magnitude lower than those that would be expected to result in adverse effects to D. savignyi embryos. Although nationally recommended chronic ambient water quality criteria, currently 8.2 and 3.1 µg L(-1) for nickel and copper, respectively, were not exceeded, recently derived qualifying toxicity data should be considered for updating these criteria to ensure protectiveness of sensitive tropical species. PMID:25573279

  5. Assessing the toxicity to fish embryos of surface water from the Watts Bar Lake/Clinch River system

    SciTech Connect

    Ivey, L.J.; Niemela, S.L.; McCracken, M.K.; Greeley, M.S. Jr.

    1995-12-31

    Successful reproduction of fish populations requires the successful development of offspring into new reproductive cohorts. In order to evaluate the ability of fish offspring to survive and develop properly in the Watts Bar Lake/Clinch River system downstream of the Department of Energy facilities in Oak Ridge, TN, a series of fish embryo-larval toxicity tests were conducted on surface water samples from Poplar Creek and the Clinch River adjacent to the Oak Ridge Reservation. Quarterly tests were conducted over an eighteen-month interval with embryos from laboratory stocks of the Japanese medaka (Oryzias latipes). Eggs obtained from largemouth bass (Micropterus salmoides) and redbreast sunfish (Lepomis auritus) collected from reference sites during their respective breeding seasons were fertilized in vitro for additional embryo-larval tests utilizing fish species indigenous to the Watts Bar/Clinch River system. Average survival of medaka embryos decreased significantly in water from Poplar Creek sites within the Oak Ridge Reservation, coincident with an increase in the prevalence of certain developmental abnormalities. Similar but less pronounced results were also obtained with redbreast sunfish embryos. Development of largemouth bass eggs was not adversely affected by any of the tested water samples. These findings suggest that the development of fish eggs and fry in certain reaches of the Watts Bar Lake/Clinch River system may be negatively impacted by activities on the Oak Ridge Reservation.

  6. Toxicity of heavy metals using sperm cell and embryo toxicity bioassays with Paracentrotus lividus (Echinodermata: Echinoidea): comparisons with exposure concentrations in the Lagoon of Venice, Italy.

    PubMed

    Novelli, Alessandra Arizzi; Losso, Chiara; Ghetti, Pier Francesco; Ghirardini, Annamaria Volpi

    2003-06-01

    Sperm cell and embryo toxicity tests using the Mediterranean sea urchin Paracentrotus lividus Lmk were performed to assess the toxicity of As3+, Cd2+, Cr3+, Ni2+, Pb2+, Cu2+, Zn2+, and Hg2+. The aim of this study was to improve information about the comparative sensitivity of sea urchin bioassays to the heavy metals, which are an important cause of contamination in the ecosystem of the Lagoon of Venice. Considering the data in mM/L, the order of toxicity is Hg2+ > Cu2+ > Zn2+ > As3+ > or = Cr3+ > or = Cd2+ > or = Pb2+ > or = Ni2+ for the sperm cell test and Hg2+ > or = Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+ > As3+ > or = Cr3+ for the embryo test. New toxicity data for metals expressed as median effective concentration (EC50) and no-observed-effect concentration (NOEC) are reported for the Mediterranean species. Accurate observations of embryotoxic effects at increasing metal concentrations were done, detecting some different behaviors in metal toxicity. Toxicity data compared with water column and pore-water concentrations recorded in the Lagoon of Venice (Italy) demonstrate the potential ability of bioassays using sea urchin to detect important contaminants in this ecosystem. PMID:12785587

  7. Toxicity of heavy metals using sperm cell and embryo toxicity bioassays with Paracentrotus lividus (Echinodermata: Echinoidea): comparisons with exposure concentrations in the Lagoon of Venice, Italy.

    PubMed

    Novelli, Alessandra Arizzi; Losso, Chiara; Ghetti, Pier Francesco; Ghirardini, Annamaria Volpi

    2003-06-01

    Sperm cell and embryo toxicity tests using the Mediterranean sea urchin Paracentrotus lividus Lmk were performed to assess the toxicity of As3+, Cd2+, Cr3+, Ni2+, Pb2+, Cu2+, Zn2+, and Hg2+. The aim of this study was to improve information about the comparative sensitivity of sea urchin bioassays to the heavy metals, which are an important cause of contamination in the ecosystem of the Lagoon of Venice. Considering the data in mM/L, the order of toxicity is Hg2+ > Cu2+ > Zn2+ > As3+ > or = Cr3+ > or = Cd2+ > or = Pb2+ > or = Ni2+ for the sperm cell test and Hg2+ > or = Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+ > As3+ > or = Cr3+ for the embryo test. New toxicity data for metals expressed as median effective concentration (EC50) and no-observed-effect concentration (NOEC) are reported for the Mediterranean species. Accurate observations of embryotoxic effects at increasing metal concentrations were done, detecting some different behaviors in metal toxicity. Toxicity data compared with water column and pore-water concentrations recorded in the Lagoon of Venice (Italy) demonstrate the potential ability of bioassays using sea urchin to detect important contaminants in this ecosystem.

  8. Comparative toxicity of lead (Pb2+), copper (Cu2+), and mixtures of lead and copper to zebrafish embryos on a microfluidic chip

    PubMed Central

    Li, Yinbao; Yang, Xiujuan; Zhang, Beibei; Pan, Jianbin; Li, Xinchun; Yang, Fan; Sun, Duanping

    2015-01-01

    Investigations were conducted to determine acute effects of Pb2+ and Cu2+ presented individually and collectively on zebrafish embryos. Aquatic safety testing requires a cheap, fast, and highly efficient platform for real-time evaluation of single and mixture of metal toxicity. In this study, we have developed a microfluidic system for phenotype-based evaluation of toxic effects of Pb2+ and Cu2+ using zebrafish (Danio rerio) embryos. The microfluidic chip is composed of a disc-shaped concentration gradient generator and 24 culture chambers, which can generate one blank solution, seven mixture concentrations, and eight single concentrations for each metal solution, thus enabling the assessment of zebrafish embryos. To test the accuracy of this new chip platform, we have examined the toxicity and teratogenicity of Pb2+ and Cu2+ on embryos. The individual and combined impact of Pb2+ and Cu2+ on zebrafish embryonic development was quantitatively assessed by recording a series of physiological indicators, such as spontaneous motion at 22 hours post fertilization (hpf), mortality at 24 hpf, heartbeat and body length at 96 hpf, etc. It was found that Pb2+ or Cu2+ could induce deformity and cardiovascular toxicity in zebrafish embryos and the mixture could induce more severe toxicity. This chip is a multiplexed testing apparatus that allows for the examination of toxicity and teratogenicity for substances and it also can be used as a potentially cost-effective and rapid aquatic safety assessment tool. PMID:25825620

  9. Influence of sediment composition on PAH toxicity using zebrafish (Danio rerio) and Japanese medaka (Oryzias latipes) embryo-larval assays.

    PubMed

    Perrichon, Prescilla; Le Bihanic, Florane; Bustamante, Paco; Le Menach, Karyn; Budzinski, Hélène; Cachot, Jérôme; Cousin, Xavier

    2014-12-01

    Due to hydrophobic and persistent properties, polycyclic aromatic hydrocarbons (PAHs) have a high capacity to accumulate in sediment. Sediment quality criteria, for the assessment of habitat quality and risk for aquatic life, include understanding the fate and effects of PAHs. In the context of European regulation (REACH and Water Framework Directive), the first objective was to assess the influence of sediment composition on the toxicity of two model PAHs, benzo[a]pyrene and fluoranthene using 10-day zebrafish embryo-larval assay. This procedure was undertaken with an artificial sediment in order to limit natural sediment variability. A suitable sediment composition might be then validated for zebrafish and proposed in a new OECD guideline for chemicals testing. Second, a comparative study of toxicity responses from this exposure protocol was then performed using another OECD species, the Japanese medaka. The potential toxicity of both PAHs was assessed through lethal (e.g., survival, hatching success) and sublethal endpoints (e.g., abnormalities, PMR, and EROD) measured at different developmental stages, adapted to the embryonic development time of both species. Regarding effects observed for both species, a suitable artificial sediment composition for PAH toxicity testing was set at 92.5 % dry weight (dw) silica of 0.2-0.5-mm grain size, 5 % dw kaolin clay without organic matter for zebrafish, and 2.5 % dw blond peat in more only for Japanese medaka. PAH bioavailability and toxicity were highly dependent on the fraction of organic matter in sediment and of the K ow coefficients of the tested compounds. The biological responses observed were also dependent of the species under consideration. Japanese medaka embryos appeared more robust than zebrafish embryos for understanding the toxicity of PAHs following a sediment contact test, due to the longer exposure duration and lower sensitivity of sediment physical properties.

  10. 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...

  11. Toxicity testing for human in vitro fertilization programs.

    PubMed

    Ackerman, S B; Stokes, G L; Swanson, R J; Taylor, S P; Fenwick, L

    1985-09-01

    Using a mouse embryo culture system, several procedures and materials associated with human in vitro fertilization protocols were tested for potential toxicity. Also, quality-control assays were performed for media prepared by nine different human in vitro fertilization programs. Detrimental effects upon embryo development were observed when culture media were exposed to the following substances: surgical instruments sterilized with Cidex or Cidex-7 or sterilized with ethylene oxide after packaging in Nest Protector Packs, various brands of surgical gloves, and various synthetic materials being evaluated as possible needle or catheter "liners." Results from comparative testing of media and serum supplements prepared by different in vitro programs indicated a wide range in culture medium quality, as assayed by the ability of the reagents to support mouse embryo development. The importance of an animal model system available to all human in vitro programs for routine quality-control analysis and testing of novel uses of materials and innovative methods is discussed.

  12. Aquatic toxicity assessment of single-walled carbon nanotubes using zebrafish embryos

    NASA Astrophysics Data System (ADS)

    Pan, Huichin; Lin, Yu-Jun; Li, Meng-Wei; Chuang, Han-Ni; Chou, Cheng-Chung

    2011-07-01

    Zebrafish embryos selected at the 64-cell stage were exposed to various concentrations of amide functionalized single-walled carbon nanotubes (SWCNTs) ranging from 1 to 10 μg/ml dissolved in 1% Pluronic F-68 (a cell culture grade surfactant), and the development of embryos was examined from 24 to 120 hours post fertilization (hpf). Incubation of embryos in 1% F-68 did not induce overt abnormal phenotype as compared to the wild-type; neither did it cause significant mortality during the exposure period. Generally, there was a slight developmental delay in larvae treated with SWCNTs of 5 μg/ml or above. Only larvae exposed to >= 5 μg/ml SWCNTs showed significantly reduced survival rates. About 50% of the embryos exposed to 5 μg/ml showed abnormal phenotypes at 24 hpf as compared to the control group. As development proceeds to 120 hpf, more embryos displayed defective morphology. A slight hatching delay was observed in embryos exposed to concentrations above 5 μg/ml. There was a general reduction of body axes, including narrowed somite and shortened yolk stalk. In addition, pigmentation in the ventral trunk area was less than that observed in control group. The body lengths of the exposed embryos were decreased significantly at 48 hpf (3.11 mm in control vs. 3.00 mm in SWCNTs-exposed embryos). However, exposure to SWCNTs did not affect the number of somites. Other features that were noticed in the SWCNTs-exposed embryos included edema and shrinkage and blebbling of the epidermal lining. Most of these observed phenotypes persisted from 48 hpf through 120 hpf. Overall, the aforementioned results indicate that soluble amide-functionalized SWCNTs are toxic to zebrafish embryos at a minimum concentration of 5 μg/ml.

  13. Toxicity testing using Caenorhabditis elegans

    SciTech Connect

    Middendorf, P.J.; Dusenbery, D.B.; Williams, P.L.

    1995-12-31

    Caenorhabditis elegans is a small free-living nematode that is representative of what may be the most abundant animal group. It has been promoted as a possible model organism for toxicity testing in the laboratory and in field evaluations in part because more is known about its biology than any other animal, Toxicity tests using C. elegans have been developed with lethality, reproduction, and behavior as end points. The tests have also been developed to varying degrees using standard laboratory media, water, and soil. The results of the tests when exposing C. elegans to a variety of metals, inorganic, and organic compounds indicate it is typically at least as sensitive as other species currently used, such as Daphnia and earthworms, and is generally much easier to maintain in the laboratory. The advantages and disadvantages of C. elegans and the state of development of the tests will be discussed.

  14. Comparison of rat and rabbit embryo-fetal developmental toxicity data for 379 pharmaceuticals: on the nature and severity of developmental effects (Critical Reviews in Toxicology)

    EPA Science Inventory

    Regulatory non-clinical safety testing of human pharmaceutical compounds typically requires embryo fetal developmental toxicity (EFDT) testing in two species, (one rodent and one non-rodent, usually the rat and the rabbit). The question has been raised whether under some conditio...

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

    PubMed

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

    2013-09-15

    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.

  16. Phytochemicals reduce aflatoxin-induced toxicity in chicken embryos

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxins (AF) are toxic metabolites produced by molds, Aspergillus flavus and Aspergillus parasicitus, which frequently contaminate chicken feed ingredients. Ingestion of AF-contaminated feed by chickens leads to deleterious effects, including decreased chicken performance and reduced egg producti...

  17. GLUCOCORTICOID RECEPTOR REGULATION IN THE RAT EMBRYO: A POTENTIAL SITE FOR DEVELOPMENTAL TOXICITY?

    EPA Science Inventory

    Glucocorticoid receptor regulation in the rat embryo: a potential site for developmental toxicity?

    Ghosh B, Wood CR, Held GA, Abbott BD, Lau C.

    National Research Council, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA.

  18. Toxicity of weathered Exxon Valdez crude oil to pink salmon embryos.

    PubMed

    Brannon, Ernest L; Collins, Keya M; Brown, John S; Neff, Jerry M; Parker, Keith R; Stubblefield, William A

    2006-04-01

    Research was conducted at the University of Idaho (Moscow, ID, USA) on the toxicity of weathered Exxon Valdez crude oil to embryos of pink salmon from 2001 to 2003 for the purpose of comparing these data with those from the National Oceanic and Atmospheric Administration Fisheries Laboratory at Auke Bay (AK, USA). Mortality reported at Auke Bay for embryos chronically exposed to very low concentrations of aqueous solutions of weathered oil, measured as dissolved polycyclic aromatic hydrocarbons (PAHs), was inconsistent with that in other published research. Using the Auke Bay experimental design, we found that toxicity is not evident in pink salmon embryos until chronic exposure to laboratory weathered and naturally weathered oil concentrations exceeding 1,500 and 2,250 ppm, respectively, representing a total PAH tissue burden in excess of 7,100 ppb. Effluent hydrocarbons also drop well below concentrations sufficient to cause harm over the time frame of a few weeks, regardless of oiling level. Resolution of differences with Auke Bay involved the source of contributing hydrocarbons. The experimental design did not exclude dispersed oil droplets from the aqueous solution; thus, toxicity was not limited to the dissolved hydrocarbon fraction. The implications of the present results are discussed regarding the toxic risk of weathered oil to pink salmon embryos in streams of Prince William Sound (AK, USA). PMID:16629135

  19. Evaluation of developmental toxicity and teratogenicity of diclofenac using Xenopus embryos.

    PubMed

    Chae, Jeong-Pil; Park, Mi Seon; Hwang, Yoo-Seok; Min, Byung-Hwa; Kim, Sang-Hyun; Lee, Hyun-Shik; Park, Mae-Ja

    2015-02-01

    Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) with analgesic and anti-pyretic properties. This compound is therefore used to treat pain, inflammatory disorders, and dysmenorrhea. Due to its multimodal mechanism of action and ability to penetrate placenta, diclofenac is known to have undesirable side effects including teratogenicity. However, limited data exist on its teratogenicity, and a detailed investigation regarding harmful effects of this drug during embryogenesis is warranted. Here, we analyzed the developmental toxic effects of diclofenac using Xenopus embryos according to the Frog Embryo Teratogenesis Assay-Xenopus (FETAX) protocol. Diclofenac treatment exerted a teratogenic effect on Xenopus embryos with a teratogenic index (TI) value of 2.64 TI; if this value is higher than 1.2, the cut-off value indicative of toxicity. In particular, mortality of embryos treated with diclofenac increased in a concentration-dependent manner and a broad spectrum of malformations such as shortening and kinking of the axis, abdominal bulging, and prominent blister formation, was observed. The shape and length of internal organs also differed compared to the control group embryos and show developmental retardation on histological label. However, the expression of major tissue-specific markers did not change when analyzed by reverse transcription-polymerase chain reaction (RT-PCR). In conclusion, diclofenac treatment can promote teratogenicity that results in morphological anomalies, but not disrupt the developmental tissue arrangement during Xenopus embryogenesis.

  20. Differential toxicity of three polychlorinated biphenyl congeners in developing sea urchin embryos

    SciTech Connect

    Schweitzer, L.E.; Suffet, I.H.; Hose, J.E.; Bay, S.M.

    1997-07-01

    The relationship between body burden and toxicity of three individual polychlorinated biphenyl (PCB) congeners in developing sea urchin embryos was investigated to evaluate the validity of current predictive models of PCB toxicity in an invertebrate system. Body burdens of radiolabeled PCB congeners (IUPAC-47, 77, and 153) accumulated from a seawater were used to determine median effective concentrations (EC50s) for developmental and cytogenetic effects following a 72-h exposure. Congener 47, a di-ortho-substituted tetrachlorobiphenyl, was found to be at least four times more toxic than congener 77, a non-ortho-substituted (coplanar) tetrachlorobiphenyl, with EC50s of 47 and >218 mmol/kg, respectively, using an embryo development assay. This result contradicts the structure-activity prediction of the mammalian-based toxic equivalents (TEQs) approach, demonstrating the need for an ecotoxicologic model. Congener 153, a di-ortho-substituted hexachlorobiphenyl, was virtually nontoxic in terms of developmental effects at the highest dose achievable at its limit of water solubility. Cytogenetic analysis was a more sensitive method for assessing toxicity than the embryo development assay. Dose-response relationships were established with mitotic activity being the most sensitive endpoint because the PCBs appeared to inhibit mitosis. At the highest doses, complete mitotic arrest was observed. Congener 77 was found to be at least two times more toxic than congener 153 but not as toxic as congener 47 using mitotic activity as the endpoint for toxicity. Thus, the developmental and cytogenetic endpoints ranked the toxicity of the congeners similarly, but established different EC50s.

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

    PubMed

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

    2014-08-01

    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 (0.1-15 mg L(-1)) until 72 h. Results showed that values of 72 h LC50 and EC50 were 7.44 and 5.60 mg L(-1) for embryos, 2.52 and 1.37 mg L(-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 (0.05 mg L(-1) for embryos and 0.01 mg L(-(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

  2. Particle-specific toxic effects of differently shaped zinc oxide nanoparticles to zebrafish embryos (Danio rerio).

    PubMed

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

    2014-12-01

    A general approach is proposed that allows for quantifying the relative toxic contribution of ions released from metallic nanoparticles and of the particles themselves, as exemplified for the case of differently shaped zinc oxide (ZnO) nanoparticles (NPs) exposed to zebrafish embryos. First of all, the toxicity of suspensions of ZnO nanoparticles (NP(total))--nanospheres, nanosticks, cuboidal submicron particles (SMPs), and Zn(NO3)2--to the embryos was assessed. The observed toxicity of ZnO NP(total) is assumed to result from the combined effect of the particles present in the suspensions (NP(particle)) and of the dissolved Zn(2+) ions released from the particles (NP(ion)). Different addition models were used to explicitly account for the toxicity of NP(particle). The median lethal concentrations (LC50) of NP(particle) of nanospheres, nanosticks, and SMPs were found to range between 7.1 mg Zn/L and 11.9 mg Zn/L (i.e., to differ by a factor of 1.7). Behavioral performance showed no significant differences among all types of the NP(particle). The median effective concentrations (EC50) of the particles were found to range between 1.0 mg Zn/L and 2.2 mg Zn/L. At the LC50 of each particle suspension, the main contribution to lethality to zebrafish embryos was from the NP(particle) (52%-72%). For hatching inhibition, the NP(particle) was responsible for 38% to 83% of the adverse effects observed. The ZnO nanosticks were more toxic than any of the other NPs with regard to the endpoints mortality and hatching inhibition. The main contribution to toxicity to zebrafish embryos was from the NP(particle) at the LC50 and EC50 of each particle suspension.

  3. Developmental toxicity of copper chloride, methylene chloride, and 6-aminonicotinamide to embryos of the grass shrimp Palaemonetes pugio

    SciTech Connect

    Rayburn, J.R.; Fisher, W.S.

    1999-05-01

    Embryos of estuarine grass shrimp Palaemonetes pugio have demonstrated sensitivity to various solvents and petroleum products, indicating utility for evaluating estuarine contamination. Testing was performed to establish concentration-response curves for methylene chloride, copper chloride, and 6-aminonicotinamide, three known teratogenic chemicals. Two exposure periods were used, 4 d and 12 d, and both periods extended through hatching. The average 4-d LC50 values for methylene chloride, copper chloride, and 6-aminonicotinamide were 0.071% v/v, 1.82 mg/L, and 0.21 mg/ml, respectively. The average 12-d LC50 values for methylene chloride, copper chloride, and 6-aminonicotinamide were 0.031% v/v, 1.44 mg/L, and 0.057 mg/ml, respectively. Eye malformations were observed with embryos exposed to concentrations greater than 3 mg/L copper chloride or greater than 0.07% v/v methylene chloride. Very few abnormalities were observed in embryos exposed to 6-aminonicotinamide. Abnormal larval development was found with exposure to copper chloride at concentrations greater than 1 mg/L. The sensitivity and low variability found here further supports the development of these relatively simple methods using grass shrimp embryos. Establishment of sublethal developmental endpoints warrants further investigation because of their potential correspondence to mechanisms of toxic action.

  4. Arsenic toxicity and HSP70 expression in Xenopus laevis embryos.

    PubMed

    Gornati, Rosalba; Monetti, Claudio; Vigetti, Davide; Bosisio, Stefano; Fortaner, Salvador; Sabbioni, Enrico; Bernardini, Giovanni; Prati, Mariangela

    2002-01-01

    The evaluation of the effect of trace metals on health can be difficult, because of their presence in the environment in various chemical forms. Exposure to arsenic compounds is an example of this complexity, as it can be present in the environment in inorganic and organic forms. The effects of arsenic in vertebrates are complicated by several variables, such as speciation of the element, the exposure route, and the susceptibility of the particular animal species. The embryotoxicity and teratogenicity of three arsenic species - sodium arsenite (NaAsO(2)), disodium hydrogen arsenate (Na(2)HAsO(4)) and dimethylarsinic acid [(CH3)2AsOOH] - were evaluated by the modified frog embryo teratogenic assay on Xenopus (FETAX). We also show how the classical FETAX endpoints, based on morphological and morphometrical analysis, can conveniently be integrated with the study of molecular markers. Possible changes in the expression of the mRNA for the heat-shock protein HSP70, following exposure to NaAsO(2), were examined by using the reverse transcriptase polymerase chain reaction. HSP70 mRNA is strongly induced by arsenic.

  5. Multifaceted toxicity assessment of catalyst composites in transgenic zebrafish embryos.

    PubMed

    Jang, Gun Hyuk; Lee, Keon Yong; Choi, Jaewon; Kim, Sang Hoon; Lee, Kwan Hyi

    2016-09-01

    Recent development in the field of nanomaterials has given rise into the inquiries regarding the toxicological characteristics of the nanomaterials. While many individual nanomaterials have been screened for their toxicological effects, composites that accompany nanomaterials are not common subjects to such screening through toxicological assessment. One of the widely used composites that accompany nanomaterials is catalyst composite used to reduce air pollution, which was selected as a target composite with nanomaterials for the multifaceted toxicological assessment. As existing studies did not possess any significant data regarding such catalyst composites, this study focuses on investigating toxicological characteristics of catalyst composites from various angles in both in-vitro and in-vivo settings. Initial toxicological assessment on catalyst composites was conducted using HUVECs for cell viability assays, and subsequent in-vivo assay regarding their direct influence on living organisms was done. The zebrafish embryo and its transgenic lines were used in the in-vivo assays to obtain multifaceted analytic results. Data obtained from the in-vivo assays include blood vessel formation, mutated heart morphology, and heart functionality change. Our multifaceted toxicological assessment pointed out that chemical composites augmented with nanomaterials can too have toxicological threat as much as individual nanomaterials do and alarms us with their danger. This manuscript provides a multifaceted assessment for composites augmented with nanomaterials, of which their toxicological threats have been overlooked. PMID:27364464

  6. Multifaceted toxicity assessment of catalyst composites in transgenic zebrafish embryos.

    PubMed

    Jang, Gun Hyuk; Lee, Keon Yong; Choi, Jaewon; Kim, Sang Hoon; Lee, Kwan Hyi

    2016-09-01

    Recent development in the field of nanomaterials has given rise into the inquiries regarding the toxicological characteristics of the nanomaterials. While many individual nanomaterials have been screened for their toxicological effects, composites that accompany nanomaterials are not common subjects to such screening through toxicological assessment. One of the widely used composites that accompany nanomaterials is catalyst composite used to reduce air pollution, which was selected as a target composite with nanomaterials for the multifaceted toxicological assessment. As existing studies did not possess any significant data regarding such catalyst composites, this study focuses on investigating toxicological characteristics of catalyst composites from various angles in both in-vitro and in-vivo settings. Initial toxicological assessment on catalyst composites was conducted using HUVECs for cell viability assays, and subsequent in-vivo assay regarding their direct influence on living organisms was done. The zebrafish embryo and its transgenic lines were used in the in-vivo assays to obtain multifaceted analytic results. Data obtained from the in-vivo assays include blood vessel formation, mutated heart morphology, and heart functionality change. Our multifaceted toxicological assessment pointed out that chemical composites augmented with nanomaterials can too have toxicological threat as much as individual nanomaterials do and alarms us with their danger. This manuscript provides a multifaceted assessment for composites augmented with nanomaterials, of which their toxicological threats have been overlooked.

  7. Potential protective effect of L-cysteine against the toxicity of acrylamide and furan in exposed Xenopus laevis embryos: an interaction study.

    PubMed

    Williams, John Russell; Rayburn, James R; Cline, George R; Sauterer, Roger; Friedman, Mendel

    2014-08-01

    The embryo toxicities of two food-processing-induced toxic compounds, acrylamide and furan, with and without added L-cysteine were examined individually and in mixtures using the frog embryo teratogenesis assay-Xenopus (FETAX). The following measures of developmental toxicity were used: (a) 96 h LC50, the median concentration causing 50% embryo lethality; (b) 96 h EC50, the median concentration causing 50% malformations of the surviving embryos; and (c) teratogenic index (96 h LC50/96 h EC50), an estimate of teratogenic risk. Calculations of toxic units (TU) were used to assess possible antagonism, synergism, or response addition of several mixtures. The evaluated compounds demonstrated counterintuitive effects. Furan had lower than expected toxicity in Xenopus embryos and, unlike acrylamide, does not seem to be teratogenic. However, the short duration of the tests may not show the full effects of furan if it is truly primarily genotoxic and carcinogenic. L-Cysteine showed unexpected properties in the delay of hatching of the embryos. The results from the interaction studies between combination of two or three components (acrylamide plus L-cysteine; furan plus L-cysteine; acrylamide plus furan; acrylamide plus furan and L-cysteine) show that furan and acrylamide seem to have less than response addition at 1:1 toxic unit ratio in lethality. Acrylamide and L-cysteine show severe antagonism even at low 19 acrylamide/1 L-cysteine TU ratios. Data from the mixture of acrylamide, furan, and L-cysteine show a slight antagonism, less than would have been expected from binary mixture exposures. Bioalkylation mechanisms and their prevention are discussed. There is a need to study the toxicological properties of mixtures of acrylamide and furan concurrently formed in heat-processed food.

  8. 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

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

    2012-06-01

    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

  9. Opportunities for embryo transfer in the age of DNA testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Embryo transfer (ET) has contributed to increasing selection intensity in cattle breeding for many years. Preimplantation DNA testing offers the opportunity to increase selection response further through increasing within-family selection intensity. Further increases in between-family selection inte...

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

    PubMed

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

    2014-04-01

    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.

  11. Assessment of the toxic effect exerted by fluorescent pseudomonads on embryos and larvae of the sea urchin Strongylocentrotus nudus.

    PubMed

    Beleneva, I A; Shamshurina, E V; Eliseikina, M G

    2015-05-01

    Strains of bacteria capable of growing on artificial culture media were isolated from the fouling of brass plates submerged in Nha Trang Bay, South China Sea, and from tissues of the seastar Distolasterias nipon, caught in Peter the Great Bay, Sea of Japan. According to the complex of data of genetic and physiological/biochemical analyzes, two strains of cultivated bacteria were identified by us as the species Pseudomonas aeruginosa, two strains as Pseudomonas fluorescens, and one strain as Ruegeria sp. It was shown that the cultivated strains of P. aeruginosa released exotoxins, particularly phenazine pigments, into the environment. Production of the toxins did not depend on presence of a target organism in the system and was aimed at regulation of interactions in the microbial community. The toxicity of the studied natural isolates of fluorescent pseudomonads was analyzed by using embryos and larvae of the sea urchin Strongylocentrotus nudus, which are the sensitive and dynamic toxicological sea-urchin embryo test (SET) system. As was established, exotoxins produced by the strains of P. aeruginosa inhibit activity of cilia in sea urchin larvae, as well as disturb processes of cell differentiation in embryos and larvae. Their toxic influence is accompanied by disturbances of protein synthesis and the disruptions of cytoskeleton in the course of zygote cleavage and larval development. Unlike P. aeruginosa, the strains of P. fluorescens and Ruegeria sp. did not exert the toxic effect on SET. The obtained data allow considering objects of the environment as the natural reservoir of opportunistic microorganisms posing a potential threat to human, whereas the use of SET for determination of toxicity of isolated bacteria provides an opportunity to study the mechanisms of their interactions with organisms in marine ecosystems.

  12. Developmental and reproductive toxicity testing of vaccines.

    PubMed

    Barrow, Paul

    2012-03-01

    The majority of new preventative and therapeutic vaccines are now assessed for developmental toxicity according to guidelines issued by the FDA in 2006. Despite the absence of confirmed effects in humans, vaccines are frequently suspected of having adverse side-effects on the development of children. Such suspicions are perhaps unavoidable considering the extremely widespread use of vaccines. The preclinical developmental toxicology studies are designed to assess possible influences of each component of the vaccine formulation-and the induced antibodies-on the development of the conceptus, neonate and suckling organism. Immune modulation by a vaccine or an adjuvant could, for instance, affect the outcome of pregnancy by interfering with the natural shift in immune balance of the mother during gestation. Maternal immunoglobulins are transferred from the mother to the offspring in order to confer passive immunity during early life. This maternal antibody transport is prenatal in humans and monkeys, but tends to be delayed until after birth in other species. Therefore, a suitable model species needs to be chosen for preclinical studies in order to ensure exposure of the foetus to the induced maternal antibodies following vaccination. Rabbits are the best laboratory model for prenatal immunoglobulin transfer, but rodents are more practical for the necessary postnatal investigations. Non-human primates are the only appropriate models for the testing of vaccines that are not immunogenic in lower species. It is advisable to test new adjuvants separately according to the ICH S5(R2) guidelines. Preclinical paediatric investigations are not currently required for vaccines, even though most vaccines are given to children. Other areas of regulatory concern include developmental immunotoxicity and effects on the preimplantation embryo. Because of the limitations of the available animal models for developmental toxicity testing, pharmacovigilance is essential.

  13. Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to embryos of the fathead minnow (Pimephales promelas, Rafinesque)

    SciTech Connect

    Olivieri, C.; Cooper, K.

    1995-12-31

    This study correlates the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) residue and its toxicity to the fathead minnow embryo exposed to levels lower than the TCDD solubility range. The TCDD tissue doses in the embryo/larvae were related to gross lesions, delayed hatching, and death. A 7-day bioconcentration factor on a lipid basis (BCF{sub L}) was calculated. Embryos at the blatsula stage were exposed to [{sup 3}H] TCDD water concentrations (0.37, 0.59, 1.2, 2.83, and 10.1 6 ng/L), a nontreatment control and a solvent carrier control. Lesions were qualified as mild and severe based on their onset and their pathogenesis. Thus, mild lesions developed just prior to hatching or post-hatching at the fifth day of development. The severe lesions appeared at the third day of development. Embryos with tissue doses {le}2.46 {+-} 1.34 ng/g consistently developed mild lesions, while embryos with tissue doses {ge} 12.07 {+-} 4.91 ng/g developed severe lesions. The lowest observable adverse effect level was 0.04 {+-} 0.02 ng/g. The calculated 7-day ED{sub 50} was 0.14 ng/g. There was no delayed hatching at any of the concentrations tested. Embryo death occurred at a tissue concentration {ge}2.46 ng/g. The calculated 7-day LD{sub 50} was 25.71 ng/g. The relationship between the concentration of TCDD in the water (x = ng/L) and in the tissue dose (y = ng/g) fitted a linear curve y = {minus}1,143 + 3,792.5x, r{sup 2} = 0.98. The calculated BCF{sub L} (wet weight) was dose dependent. Embryos with tissue doses of 0.04 and 0.16 ng/g had BCF{sub L} of 2,700 and 3,325, respectively. Embryos with tissue doses of 2.46, 12.07, and 37.07 ng/g, had a BCF{sub L} of 104,225, 106,625 and 91,075, respectively.

  14. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes) embryos.

    PubMed

    Dong, Wu; Liu, Jie; Wei, Lixin; Jingfeng, Yang; Chernick, Melissa; Hinton, David E

    2016-01-01

    This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes) embryos were exposed to 0.001-10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha), and β-HgS (Zuotai) from stage 10 (6-7 hpf) to 10 days post fertilization (dpf). Of the forms of mercury in this study, the organic form (MeHg) proved the most toxic followed by inorganic mercury (HgCl2), both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM), HgCl2 (1 µM), α-HgS (10 µM), or β-HgS (10 µM) to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT) and heme oxygenase-1 (Ho-1), while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity. PMID:27635309

  15. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes) embryos

    PubMed Central

    Liu, Jie; Wei, Lixin; Jingfeng, Yang; Chernick, Melissa; Hinton, David E.

    2016-01-01

    This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes) embryos were exposed to 0.001–10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha), and β-HgS (Zuotai) from stage 10 (6–7 hpf) to 10 days post fertilization (dpf). Of the forms of mercury in this study, the organic form (MeHg) proved the most toxic followed by inorganic mercury (HgCl2), both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM), HgCl2 (1 µM), α-HgS (10 µM), or β-HgS (10 µM) to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT) and heme oxygenase-1 (Ho-1), while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity. PMID:27635309

  16. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes) embryos

    PubMed Central

    Liu, Jie; Wei, Lixin; Jingfeng, Yang; Chernick, Melissa; Hinton, David E.

    2016-01-01

    This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes) embryos were exposed to 0.001–10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha), and β-HgS (Zuotai) from stage 10 (6–7 hpf) to 10 days post fertilization (dpf). Of the forms of mercury in this study, the organic form (MeHg) proved the most toxic followed by inorganic mercury (HgCl2), both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM), HgCl2 (1 µM), α-HgS (10 µM), or β-HgS (10 µM) to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT) and heme oxygenase-1 (Ho-1), while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity.

  17. Polyamide Nanogels from GRAS Components and Their Toxicity in Mouse Pre-implantation Embryos

    PubMed Central

    Prasad, Priyaa; Molla, Mijanur Rahaman; Cui, Wei; Canakci, Mine; Osborne, Barbara; Mager, Jesse; Thayumanavan, S.

    2016-01-01

    Safe delivery systems that can not only encapsulate hydrophobic drug molecules, but also release them in response to specific triggers, are important in several therapeutic and biomedical applications. In this paper, we have designed a nanogel based on molecules that are generally recognized as safe (GRAS). We have shown that the resultant polymeric nanogels exhibit responsive molecular release, and also show high in vitro cellular viability on HEK 293T, HeLa, MCF 7 and A549 cell lines. The toxicity of these nanogels was further evaluated with a highly sensitive assay using mouse preimplantation embryo development, where blastocysts were formed after four days of in vitro culture and live pups were born when morulae/early blastocysts were transferred to the uteri of surrogate recipients. Our results indicate that these nanogels are non-toxic during mammalian development and do not alter normal growth or early embryo success rate. PMID:26367020

  18. Combined toxicity of silica nanoparticles and methylmercury on cardiovascular system in zebrafish (Danio rerio) embryos.

    PubMed

    Duan, Junchao; Hu, Hejing; Li, Qiuling; Jiang, Lizhen; Zou, Yang; Wang, Yapei; Sun, Zhiwei

    2016-06-01

    This study was to investigate the combined toxicity of silica nanoparticles (SiNPs) and methylmercury (MeHg) on cardiovascular system in zebrafish (Danio rerio) embryos. Ultraviolet absorption analysis showed that the co-exposure system had high absorption and stability. The dosages used in this study were based on the NOAEL level. Zebrafish embryos exposed to the co-exposure of SiNPs and MeHg did not show any cardiovascular malformation or atrioventricular block, but had an inhibition effect on bradycardia. Using o-Dianisidine for erythrocyte staining, the cardiac output of zebrafish embryos was decreased gradually in SiNPs, MeHg, co-exposure groups, respectively. Co-exposure of SiNPs and MeHg enhanced the vascular endothelial damage in Tg(fli-1:EGFP) transgenic zebrafish line. Moreover, the co-exposure significantly activated the oxidative stress and inflammatory response in neutrophils-specific Tg(mpo:GFP) transgenic zebrafish line. This study suggested that the combined toxic effects of SiNPs and MeHg on cardiovascular system had more severe toxicity than the single exposure alone.

  19. Embryo-fetal development toxicity of honokiol microemulsion intravenously administered to pregnant rats.

    PubMed

    Zhang, Qianqian; Ye, Xiangfeng; Wang, Lingzhi; Peng, Bangjie; Zhang, Yingxue; Bao, Jie; Li, Wanfang; Wei, Jinfeng; Wang, Aiping; Jin, Hongtao; Chen, Shizhong

    2016-02-01

    The aim of this study was to evaluate the embryo-fetal development toxicity of honokiol microemulsion. The drug was intravenously injected to pregnant SD rats at dose levels of 0, 200, 600 and 2000 μg/kg/day from day 6-15 of gestation. All the pregnant animals were observed for body weights and any abnormal changes and subjected to caesarean-section on gestation day (GD) 20; all fetuses obtained from caesarean-section were assessed by external inspection, visceral and skeletal examinations. No treatment-related external alterations as well as visceral and skeletal malformations were observed in honokiol microemulsion groups. There was no significant difference in the body weight gain of the pregnant rats, average number of corpora lutea, and the gravid uterus weight in the honokiol microemulsion groups compared with the vehicle control group. However, at a dose level of 2000 μg/kg/day, there was embryo-fetal developmental toxicity observed, including a decrease in the body length and tail length of fetuses. In conclusion, the no-observed-adverse-effect level (NOAEL) of honokiol microemulsion is 600 μg/kg/day, 75 times above the therapeutic dosage and it has embryo-fetal toxicity at a dose level of 2000 μg/kg/day, which is approximately 250 times above the therapeutic dosage.

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

    PubMed

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

    2005-09-01

    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 (reference). Elutriate was chosen as sediment matrix to assess the potential effects of bioavailable pollutants in the water column as a consequence of sediment resuspension (dredging and dumping, fishing gear, etc.). An experimental design based on Quality Assurance/Quality Control procedures (QA/QC) was adopted in order to set the methodological basis for an effective use of these bioassays in monitoring programs. Results revealed both higher embriotoxicity than spermiotoxicity in all stations and the efficacy of combined use of both toxicity bioassays in discriminating differing pollution/bioavailability between stations and periods. The good representativeness of the integrated sampling scheme and the standardization of all experimental phases yielded high precision of results. Clear Toxicity Fingerprints were evidenced for the investigated sites through the combined use of both bioassays. A good fit between ecotoxicological data and chemical contamination levels was found, except for unnatural sediment texture. PMID:16019068

  1. Is UV radiation changing the toxicity of compounds to zebrafish embryos?

    PubMed

    Almeida, Ana Rita; Andrade, Thayres S; Burkina, Viktoriia; Fedorova, Ganna; Loureiro, Susana; Soares, Amadeu M V M; Domingues, Inês

    2015-12-01

    At ecosystems level, environmental parameters such as temperature, pH, dissolved oxygen concentration and intensity of UV radiation (UVR) have an important role on the efficiency of organisms' physiological and behavioral performances and consequently on the capacity of response to contaminants. Insignificant alterations of these parameters may compromise this response. In addition, these parameters can additionally alter chemical compounds by inducing their degradation, producing thereafter other metabolites. Understanding the combined effects of chemicals and environmental parameters is absolutely necessary for an adequate prediction of risk in aquatic environments. According to this scenario, this work aims at studying the combined toxicity of UVR and three xenobiotics: the biocide triclosan (TCS), the metal chromium (as potassium dichromate, PD) and the fungicide prochloraz (PCZ). To achieve this goal zebrafish (Danio rerio) embryos (3h post fertilization (hpf)) were exposed to several concentrations of each chemical combined with different UV intensities; mortality and eggs were recorded every 24h for the all test duration (96 h). Results showed different response patterns depending on the toxicant, stress levels and duration of exposure. The combination of UVR and TCS indicated a dose ratio deviation where synergism was observed when UVR was the dominant stressor (day 2). The combination of UVR and PD presented a dose level dependency at day 3 indicating antagonism at low stress levels, changing with time where at day 4, a dose ratio deviation showed statistically that synergism occurred at higher PD concentrations. Finally, UVR combined with PCZ indicated a dose ratio at day 3 and dose level deviation at day 4 of exposure, suggesting a synergistic response when PCZ is the dominant stressor in the combination. The obtained results in this study highlighted the importance of taking into account the possible interaction of stressors and time of exposure to

  2. AHR2 morpholino knockdown reduces the toxicity of total particulate matter to zebrafish embryos.

    PubMed

    Massarsky, Andrey; Bone, Audrey J; Dong, Wu; Hinton, David E; Prasad, G L; Di Giulio, Richard T

    2016-10-15

    The zebrafish embryo has been proposed as a 'bridge model' to study the effects of cigarette smoke on early development. Previous studies showed that exposure to total particulate matter (TPM) led to adverse effects in developing zebrafish, and suggested that the antioxidant and aryl hydrocarbon receptor (AHR) pathways play important roles. This study investigated the roles of these two pathways in mediating TPM toxicity. The study consisted of four experiments. In experiment I, zebrafish embryos were exposed from 6h post fertilization (hpf) until 96hpf to TPM0.5 and TPM1.0 (corresponding to 0.5 and 1.0μg/mL equi-nicotine units) in the presence or absence of an antioxidant (N-acetyl cysteine/NAC) or a pro-oxidant (buthionine sulfoximine/BSO). In experiment II, TPM exposures were performed in embryos that were microinjected with nuclear factor erythroid 2-related factor 2 (Nrf2), AHR2, cytochrome P450 1A (CYP1A), or CYP1B1 morpholinos, and deformities were assessed. In experiment III, embryos were exposed to TPM, and embryos/larvae were collected at 24, 48, 72, and 96hpf to assess several genes associated with the antioxidant and AHR pathways. Lastly, experiment IV assessed the activity and protein levels of CYP1A and CYP1B1 after exposure to TPM. We demonstrate that the incidence of TPM-induced deformities was generally not affected by NAC/BSO treatments or Nrf2 knockdown. In contrast, AHR2 knockdown reduced, while CYP1A or CYP1B1 knockdowns elevated the incidence of some deformities. Moreover, as shown by gene expression the AHR pathway, but not the antioxidant pathway, was induced in response to TPM exposure, providing further evidence for its importance in mediating TPM toxicity.

  3. AHR2 morpholino knockdown reduces the toxicity of total particulate matter to zebrafish embryos.

    PubMed

    Massarsky, Andrey; Bone, Audrey J; Dong, Wu; Hinton, David E; Prasad, G L; Di Giulio, Richard T

    2016-10-15

    The zebrafish embryo has been proposed as a 'bridge model' to study the effects of cigarette smoke on early development. Previous studies showed that exposure to total particulate matter (TPM) led to adverse effects in developing zebrafish, and suggested that the antioxidant and aryl hydrocarbon receptor (AHR) pathways play important roles. This study investigated the roles of these two pathways in mediating TPM toxicity. The study consisted of four experiments. In experiment I, zebrafish embryos were exposed from 6h post fertilization (hpf) until 96hpf to TPM0.5 and TPM1.0 (corresponding to 0.5 and 1.0μg/mL equi-nicotine units) in the presence or absence of an antioxidant (N-acetyl cysteine/NAC) or a pro-oxidant (buthionine sulfoximine/BSO). In experiment II, TPM exposures were performed in embryos that were microinjected with nuclear factor erythroid 2-related factor 2 (Nrf2), AHR2, cytochrome P450 1A (CYP1A), or CYP1B1 morpholinos, and deformities were assessed. In experiment III, embryos were exposed to TPM, and embryos/larvae were collected at 24, 48, 72, and 96hpf to assess several genes associated with the antioxidant and AHR pathways. Lastly, experiment IV assessed the activity and protein levels of CYP1A and CYP1B1 after exposure to TPM. We demonstrate that the incidence of TPM-induced deformities was generally not affected by NAC/BSO treatments or Nrf2 knockdown. In contrast, AHR2 knockdown reduced, while CYP1A or CYP1B1 knockdowns elevated the incidence of some deformities. Moreover, as shown by gene expression the AHR pathway, but not the antioxidant pathway, was induced in response to TPM exposure, providing further evidence for its importance in mediating TPM toxicity. PMID:27576004

  4. Comparative study of non-invasive methods for assessing Daphnia magna embryo toxicity.

    PubMed

    Stensberg, Matthew C; Zeitchek, Michael Anthony; Inn, Kul; McLamore, Eric S; Porterfield, D Marshall; Sepúlveda, Maria S

    2014-09-01

    Embryos, unlike adults, are typically sessile, which allows for an increase in the available metrics that can be used to assess chemical toxicity. We investigate Daphnia magna development rate and oxygen consumption as toxicity metrics and compare them to arrested embryo development using four different techniques with potassium cyanide (KCN) as a common toxicant. The EC50 (95 % CI) for arrested development was 2,535 (1,747-3,677) μg/L KCN. Using pixel intensity changes, recorded with difference imaging, we semi-quantitatively assessed a decrease in development rate at 200 μg/L KCN, threefold lower than the arrested development lowest observed effect concentration (LOEC). Respirometry and self-referencing (SR) microsensors were two unique techniques used to assess oxygen consumption. Using respirometry, an increase in oxygen consumption was found in the 5 μg/L KCN treatment and a decrease for 148 μg/L, but no change was found for the 78 μg/L KCN treatment. Whereas, with SR microsensors, we were able to detect significant changes in oxygen consumption for all three treatments: 5, 78, and 148 μg/L KCN. While SR offered the highest sensitivity, the respirometry platform developed for this study was much easier to use to measure the same endpoint. Oxygen consumption may be subject to change during the development process, meaning consumption assessment techniques may only be useful only for short-term experiments. Development rate was a more sensitive endpoint though was only reliable four of the six embryonic developmental stages examined. Despite being the least sensitive endpoint, arrested embryo development was the only technique capable of assessing the embryos throughout all developmental stages. In conclusion, each metric has advantages and limitations, but because all are non-invasive, it is possible to use any combination of the three. PMID:24888613

  5. Amphibian embryos as a biological test for environmental pollutants in leachates, industrial effluents, surface and ground water

    SciTech Connect

    Herkovits, J.; Perez-Coll, C.S.; Herkovits, F.D.; Tarlato, M.

    1995-12-31

    Test of early life stages are very sensitive to toxic effects and moreover a good predictive correlation between embryo-larval survival and independent ecological parameters such as species richness and diversity have been established. The main purpose of this preliminary study is to report that Bufo arenarum embryos are very sensitive to contaminants from a variety of sources such as leachates, industrial effluents, surface and ground water. The toxicity of 30 samples (five from each category plus controls of surface and ground water from reference places) was evaluated during a 14 day renewal toxicity test at 20 C, conducted with 10 embryos (by triplicate) from stage 23--25 onwards using six concentrations (V/V) of each sample of Holtfreter`s solution. For industrial effluents and leachates the results range from a concentration of 0.6% resulting in 24hs LC100 up to a sample which exert 20% of lethality after 14 days of treatment. The survival of controls and in samples from reference places was over 90% for 7 days and over 80% for 14 days. The results with Bufo arenarum embryos confirm that a 7 day Short-term Chronic Toxicity Test is appropriate for toxicity screening of industrial effluents (as it was established by EPA for whole effluent toxicity test for aquatic life protection performed with other species) as well as for leachates. On the other hand, for freshwater (surface and ground), it is convenient to extend the exposure period until 14 days in order to record situations of low, but significant levels of toxicity, which could be of particular value for surface as well as ground water quality criteria.

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

    PubMed

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

    2014-03-01

    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.

  7. Stage-dependent toxicity of bisphenol a on Rhinella arenarum (anura, bufonidae) embryos and larvae.

    PubMed

    Wolkowicz, Ianina R Hutler; Herkovits, Jorge; Pérez Coll, Cristina S

    2014-02-01

    The acute and chronic toxicity of bisphenol A (BPA) was evaluated on the common South American toad Rhinella arenarum embryos and larvae by means of continuous and pulse exposure treatments. Embryos were treated continuously from early blastula (S.4) up to complete operculum (S.25), during early larval stages and by means of 24 h pulse exposures of BPA in concentrations ranging between 1.25 and 40 mg L(-1) , in order to evaluate the susceptibility to this compound in different developmental stages. For lethal effects, S.25 was the most sensitive and gastrula was the most resistant to BPA. The Teratogenic Index for neurula, the most sensitive embryonic stage for sublethal effects was 4.7. The main morphological alterations during early stages were: delayed or arrested development, reduced body size, persistent yolk plug, microcephaly, axial/tail flexures, edemas, blisters, waving fin, underdeveloped gills, mouth malformations, and cellular dissociation. BPA caused a remarkable narcotic effect from gill circulation stage (S.20) onwards in all the organisms exposed after 3 h of treatment with 10 mg L(-1) BPA. After recovering, the embryos exhibited scarce response to stimuli, erratic or circular swimming, and spasmodic contractions from 5 mg L(-1) onwards. Our results highlight the lethal and sublethal effectsof BPA on R. arenarum embryos and larvae, in the last case both at structural and functional levels.

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

    USGS Publications Warehouse

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

    2008-01-01

    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.

  9. Sea urchin embryos as an in vivo model for the assessment of manganese toxicity: developmental and stress response effects.

    PubMed

    Pinsino, Annalisa; Matranga, Valeria; Trinchella, Francesca; Roccheri, Maria Carmela

    2010-03-01

    In the marine environment increasing concentrations of bio-available compounds often result from anthropogenic activities. Among metal ions, manganese represents a new emergent factor in environmental contamination. Here, we studied the effects of manganese on Paracentrotus lividus sea urchin embryos using biological and biochemical approaches for the analysis of impact on development, tissue accumulation and stress markers. Embryos were continuously exposed from fertilization to manganese at concentrations ranging from 1.0 to 61.6 mg l(-1), monitored for developmental abnormalities at 48 h after fertilization, and used for atomic spectrometric analysis at various times from 6 to 72 h. We found that concentration- and time-dependent increases in morphological abnormalities were directly correlated to manganese accumulation, with major defects in skeleton formation at 48 h. Concurrently, we found an upregulation of the hsc70 and hsc60 stress proteins detected by immunoblotting, whereas no induction of apoptosis or ROS production was observed by TUNEL and live tests, respectively. Taken together, our findings demonstrate that the observed manganese embryo-toxicity is related to both its intracellular accumulation and misregulated homeostasis, and confirm the importance of stress proteins as protective agents in the acquisition of tolerance and resistance to apoptosis. PMID:19882348

  10. Reproductive and developmental toxicity testing: Examination of the extended one-generation reproductive toxicity study guideline.

    PubMed

    Saghir, Shakil A; Dorato, Michael A

    2016-08-01

    An important aspect of safety assessment of chemicals (industrial and agricultural chemicals and pharmaceuticals) is determining their potential reproductive and developmental toxicity. A number of guidelines have outlined a series of separate reproductive and developmental toxicity studies from fertilization through adulthood and in some cases to second generation. The Extended One-Generation Reproductive Toxicity Study (EOGRTS) is the most recent and comprehensive guideline in this series. EOGRTS design makes toxicity testing progressive, comprehensive, and efficient by assessing key endpoints across multiple life-stages at relevant doses using a minimum number of animals, combining studies/evaluations and proposing tiered-testing approaches based on outcomes. EOGRTS determines toxicity during preconception, development of embryo/fetus and newborn, adolescence, and adults, with specific emphasis on the nervous, immunological, and endocrine systems, EOGRTS also assesses maternal and paternal toxicity. However, EOGRTS guideline is complex, criteria for selecting doses is unclear, and monitoring systemic dose during the course of the study for better interpretation and human relevance is not clear. This paper discusses potential simplification of EOGRTS, suggests procedures for relevant dose selection and monitors systemic dose at multiple life-stages for better interpretation of data and human relevance.

  11. Polyamide Nanogels from Generally Recognized as Safe Components and Their Toxicity in Mouse Preimplantation Embryos.

    PubMed

    Prasad, Priyaa; Molla, Mijanur Rahaman; Cui, Wei; Canakci, Mine; Osborne, Barbara; Mager, Jesse; Thayumanavan, S

    2015-11-01

    Safe delivery systems that can not only encapsulate hydrophobic drug molecules, but also release them in response to specific triggers are important in several therapeutic and biomedical applications. In this paper, we have designed a nanogel based on molecules that are generally recognized as safe (GRAS). We have shown that the resultant polymeric nanogels exhibit responsive molecular release and also show high in vitro cellular viability on HEK 293T, HeLa, MCF 7, and A549 cell lines. The toxicity of these nanogels was further evaluated with a highly sensitive assay using mouse preimplantation embryo development, where blastocysts were formed after 4 days of in vitro culture, and live pups were born when morulae/early blastocysts were transferred to the uteri of surrogate recipients. Our results indicate that these nanogels are nontoxic during mammalian development and do not alter normal growth or early embryo success rate. PMID:26367020

  12. Toxicity assessment and bioaccumulation in zebrafish embryos exposed to carbon nanotubes suspended in Pluronic® F-108

    PubMed Central

    Wang, Ruhung; Meredith, Alicea N.; Lee, Michael; Deutsch, Dakota; Miadzvedskaya, Lizaveta; Braun, Elizabeth; Pantano, Paul; Harper, Stacey; Draper, Rockford

    2015-01-01

    Carbon nanotubes (CNTs) are often suspended in Pluronic® surfactants by sonication, which may confound toxicity studies because sonication of surfactants can create degradation products that are toxic to mammalian cells. Here, we present a toxicity assessment of Pluronic® F-108 with and without suspended CNTs using embryonic zebrafish as an in vivo model. Pluronic® sonolytic degradation products were toxic to zebrafish embryos just as they were to mammalian cells. When the toxic Pluronic® fragments were removed, there was little effect of pristine multi-walled CNTs (pMWNTs), carboxylated MWNTs (cMWNTs) or pristine single-walled carbon nanotubes (pSWNTs) on embryo viability and development, even at high concentrations. A gel electrophoretic method coupled with Raman imaging was developed to measure the bioaccumulation of CNTs by zebrafish embryos, and dose-dependent uptake of CNTs was observed. These data indicate that embryos accumulate pMWNTs, cMWNTs and pSWNTs yet there is very little embryo toxicity. PMID:26559437

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

    PubMed

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

    2014-02-15

    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.

  14. POREWATER TOXICITY TESTING: AN OVERVIEW

    EPA Science Inventory

    Sediments act as sinks for contaminants, where they may build up to toxic levels. Sediments containing toxic levels of contaminants pose a risk to aquatic life, human health, and wildlife. There is an overwhelming amount of evidence that demonstrates chemicals in sediments are re...

  15. Toxicity of dissolved Cu, Zn, Ni and Cd to developing embryos of the blue mussel (Mytilus trossolus) and the protective effect of dissolved organic carbon.

    PubMed

    Nadella, Sunita R; Fitzpatrick, John L; Franklin, Natasha; Bucking, Carol; Smith, Scott; Wood, Chris M

    2009-04-01

    Marine water quality criteria for metals are largely driven by the extremely sensitive embryo-larval toxicity of Mytilus sp. Here we assess the toxicity of four dissolved metals (Cu, Zn, Ni, Cd) in the mussel Mytilus trossolus, at various salinity levels while also examining the modifying effects of dissolved organic carbon (DOC) on metal toxicity. In 48 h embryo development tests in natural seawater, measured EC50 values were 6.9-9.6 microg L(-1) (95% C.I.=5.5-10.8 microg L(-1)) for Cu, 99 microg L(-1) (86-101) for Zn, 150 microg L(-1) (73-156) for Ni, and 502 microg L(-1) (364-847) for Cd. A salinity threshold of >20 ppt (approximately 60% full strength seawater) was required for normal control development. Salinity in the 60-100% range did not alter Cu toxicity. Experimental addition of dissolved organic carbon (DOC) from three sources reduced Cu toxicity; for example the EC50 of embryos developing in seawater with 20 mg C L(-1) was 39 microg Cu L(-1) (35.2-47.2) a 4-fold increase in Cu EC50. The protective effects of DOC were influenced by their distinct physicochemical properties. Protection appears to be related to higher fulvic acid and lower humic acid content as operationally defined by fluorescence spectroscopy. The fact that DOC from freshwater sources provides protection against Cu toxicity in seawater suggests that extrapolation from freshwater toxicity testing may be possible for saltwater criteria development, including development of a saltwater Biotic Ligand Model for prediction of Cu toxicity.

  16. 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...

  17. Potential protective effect of L-cysteine against the toxicity of acrylamide and furan in exposed Xenopus laevis embryos: an interaction study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The embryo toxicities of two food-processing-induced toxic compounds, acrylamide and furan, with and without added L-cysteine were examined individually and in mixtures using the frog embryo teratogenesis assay-Xenopus (FETAX). The following measures of developmental toxicity were used (a) 96-h LC5...

  18. The status of toxicity tests with sediment in Brazil

    SciTech Connect

    Araujo, R.P.A.

    1995-12-31

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

  19. Zebrafish: as an integrative model for twenty-first century toxicity testing.

    PubMed

    Sipes, Nisha S; Padilla, Stephanie; Knudsen, Thomas B

    2011-09-01

    The zebrafish embryo is a useful small model for investigating vertebrate development because of its transparency, low cost, transgenic and morpholino capabilities, conservation of cell signaling, and concordance with mammalian developmental phenotypes. From these advantages, the zebrafish embryo has been considered as an alternative model for traditional in vivo developmental toxicity screening. The use of this organism in conjunction with traditional in vivo developmental toxicity testing has the potential to reduce cost and increase throughput of testing the chemical universe, prioritize chemicals for targeted toxicity testing, generate predictive models of developmental toxicants, and elucidate mechanisms and adverse outcome pathways for abnormal development. This review gives an overview of the zebrafish embryo for pre dictive toxicology and 21st century toxicity testing. Developmental eye defects were selected as an example to evaluate data from the U.S. Environmental Protection Agency's ToxCast program comparing responses in zebrafish embryos with those from pregnant rats and rabbits for a subset of 24 environmental chemicals across >600 in vitro assay targets. Cross-species comparisons implied a common basis for biological pathways associated with neuronal defects, extracellular matrix remodeling, and mitotic arrest. PMID:21932434

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

    PubMed Central

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

    2012-01-01

    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 μg/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. PMID:19087885

  1. Development of toxicant identification procedures for whole sediment toxicity tests

    SciTech Connect

    Mount, D.R.; Henke, C.E.; Ingersoll, C.G.; Besser, J.M.; Ankley, G.T.; Norberg-King, T.J.; West, C.W.

    1995-12-31

    To effectively assess and manage contaminated sediments, identifying the specific contaminants responsible for sediment toxicity is highly desirable. Though effective toxicity identification evaluation (TIE) methods are well established for water column toxicity, new TIE methodologies are needed that address the special characteristics of whole sediment toxicity tests. Much of the effort to date has focused on the assessment of ammonia toxicity. Whereas pH manipulation is a key tool used to characterize ammonia toxicity in water column TIE, control of pH in interstitial water is much more challenging. Direct addition of hard acid has shown undesirable side effects (e.g., liberation and oxidation of iron), while CO{sub 2}-enrichment is limited in penetration of fine-grained sediments. Biological buffers (MES and POPSO) incorporated into the sediment are effective at altering interstitial pH without causing direct toxicity to Chironomus tentans, Lumbriculus variegatus, and to a lesser extent Hyalella azteca, but the range of pH control achieved has been small ({+-} 0.5 units). Introduction of aquatic plants reduces ammonia concentrations in the water column, but may not provide sufficient control of interstitial water. To date, the most promising results have been achieved using zeolite; adding zeolite to sediment produces moderate reductions in interstitial ammonia concentrations and is non-toxic to the organisms referenced above. Attempts to induce microbial removal of ammonia have been unsuccessful thus far. This presentation will review these and other sediment TIE methods currently under development in laboratories.

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

    PubMed Central

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

    2014-01-01

    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 μM) from 6 to 120 hour post-fertilization (hpf). The LC50 at 120 hpf was 4.39 μM and the EC50 at 120 hpf was 2.23 μM. 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 (0.5-8.0μM) for only 1 h at 6 dpf swam faster with increasing PFOS concentration. Larvae exposed to 16.0 μM 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. PMID:20171748

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

    PubMed

    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

    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.

  4. Toxicity and cardiac effects of carbaryl in early developing zebrafish (Danio rerio) embryos

    SciTech Connect

    Lin, C.C.; Hui, Michelle N.Y.; Cheng, S.H. E-mail: bhcheng@cityu.edu.hk

    2007-07-15

    Carbaryl, an acetylcholinesterase inhibitor, is known to be moderately toxic to adult zebrafish and has been reported to cause heart malformations and irregular heartbeat in medaka. We performed experiments to study the toxicity of carbaryl, specifically its effects on the heart, in early developing zebrafish embryos. LC50 and EC50 values for carbaryl at 28 h post-fertilization were 44.66 {mu}g/ml and 7.52 {mu}g/ml, respectively, and 10 {mu}g/ml carbaryl was used in subsequent experiments. After confirming acetylcholinesterase inhibition by carbaryl using an enzymatic method, we observed red blood cell accumulation, delayed hatching and pericardial edema, but not heart malformation as described in some previous reports. Our chronic exposure data also demonstrated carbaryl-induced bradycardia, which is a common effect of acetylcholinesterase inhibitors due to the accumulation of acetylcholine, in embryos from 1 day post-fertilization (dpf) to 5 dpf. The distance between the sinus venosus, the point where blood enters the atrium, and the bulbus arteriosus, the point where blood leaves the ventricle, indicated normal looping of the heart tube. Immunostaining of myosin heavy chains with the ventricle-specific antibody MF20 and the atrium-specific antibody S46 showed normal development of heart chambers. At the same time, acute exposure resulted in carbaryl-induced bradycardia. Heart rate dropped significantly after a 10-min exposure to 100 {mu}g/ml carbaryl but recovered when carbaryl was removed. The novel observation of carbaryl-induced bradycardia in 1- and 2-dpf embryos suggested that carbaryl affected cardiac function possibly through an alternative mechanism other than acetylcholinesterase inhibition such as inhibition of calcium ion channels, since acetylcholine receptors in zebrafish are not functional until 3 dpf. However, the exact nature of this mechanism is currently unknown, and thus further studies are required.

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

    PubMed

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

    2013-07-15

    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

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

    NASA Astrophysics Data System (ADS)

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

    2013-05-01

    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 μg/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.

  7. Literature review on duckweed toxicity testing

    SciTech Connect

    Wang, W. )

    1990-06-01

    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. 76 references.

  8. Literature review on duckweed toxicity testing.

    PubMed

    Wang, W

    1990-06-01

    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.

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

    PubMed

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

    2014-04-01

    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.

  10. Toxicity assessment of peptaibols and contaminated sediments on Crassostrea gigas embryos.

    PubMed

    Poirier, Laurence; Quiniou, Françoise; Ruiz, Nicolas; Montagu, Monique; Amiard, Jean-Claude; Pouchus, Yves François

    2007-08-01

    Peptaibols are known membrane-modifying peptides that were recently detected in marine sediments and mussels collected from a shellfish farming area (Fier d'Ars, Atlantic coast, France). In this investigation, embryotoxicity bioassays with oysters (Crassostrea gigas) were performed to assess acute toxicity of alamethicin and different groups of peptaibols produced by a Trichoderma longibrachiatum strain isolated from marine environment. C. gigas embryos appeared very sensitive to all the metabolites examined with higher toxic effects for long-sequence peptides (EC50 ranging from 10 to 64 nM). D-shaped larvae with mantle abnormality were particularly noticed when peptaibol concentrations increased. Disturbances of embryogenesis were also observed following exposure to organic and aqueous extract of sediments from Fier d'Ars (EC50=42.4 and 6.6 g L(-1) dry weight, respectively). Although peptaibol concentrations measured in these sediments could explain only a part of the toxic effects observed, this study suggests that these mycotoxins can induce larval abnormalities in a population of exposed animals at environmentally realistic concentrations. Their detection in coastal areas devoted to bivalve culture should be taken into account.

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

    SciTech Connect

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

    1995-10-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus 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.

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

    SciTech Connect

    Toussaint, M.W.; Shedd, T.R.; Schalie, W.H. van der; Leather, G.R.

    1995-05-01

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

  13. 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...

  14. Automated Test Systems for Toxic Vapor Detectors

    NASA Technical Reports Server (NTRS)

    Mattson, C. B.; Hammond, T. A.; Schwindt, C. J.

    1997-01-01

    The NASA Toxic Vapor Detection Laboratory (TVDL) at the Kennedy Space Center (KSC), Florida, has been using Personal Computer based Data Acquisition and Control Systems (PCDAS) for about nine years. These systems control the generation of toxic vapors of known concentrations under controlled conditions of temperature and humidity. The PCDAS also logs the test conditions and the test article responses in data files for analysis by standard spreadsheets or custom programs. The PCDAS was originally developed to perform standardized qualification and acceptance tests in a search for a commercial off-the-shelf (COTS) toxic vapor detector to replace the hydrazine detectors for the Space Shuttle launch pad. It has since become standard test equipment for the TVDL and is indispensable in producing calibration standards for the new hydrazine monitors at the 10 part per billion (ppb) level. The standard TVDL PCDAS can control two toxic vapor generators (TVG's) with three channels each and two flow/ temperature / humidity (FTH) controllers and it can record data from up to six toxic vapor detectors (TVD's) under test and can deliver flows from 5 to 50 liters per minute (L/m) at temperatures from near zero to 50 degrees Celsius (C) using an environmental chamber to maintain the sample temperature. The concentration range for toxic vapors depends on the permeation source installed in the TVG. The PCDAS can provide closed loop control of temperature and humidity to two sample vessels, typically one for zero gas and one for the standard gas. This is required at very low toxic vapor concentrations to minimize the time required to passivate the sample delivery system. Recently, there have been several requests for information about the PCDAS by other laboratories with similar needs, both on and off KSC. The purpose of this paper is to inform the toxic vapor detection community of the current status and planned upgrades to the automated testing of toxic vapor detectors at the

  15. Automated Test Systems for Toxic Vapor Detectors

    NASA Technical Reports Server (NTRS)

    Mattson, C. B.; Hammond, T. A.; Schwindt, C. J.

    1997-01-01

    The NASA Toxic Vapor Detection Laboratory (TVDL) at the Kennedy Space Center (KSC), Florida, has been using Personal Computer based Data Acquisition and Control Systems (PCDAS) for about nine years. These systems control the generation of toxic vapors of known concentrations under controlled conditions of temperature and humidity. The PCDAS also logs the test conditions and the test article responses in data files for analysis by standard spreadsheets or custom programs. The PCDAS was originally developed to perform standardized qualification and acceptance tests in a search for a commercial off-the-shelf (COTS) toxic vapor detector to replace the hydrazine detectors for the Space Shuttle launch pad. It has since become standard test equipment for the TVDL and is indispensable in producing calibration standards for the new hydrazine monitors at the 10 part per billion (ppb) level. The standard TVDL PCDAS can control two toxic vapor generators (TVG's) with three channels each and two flow/temperature/humidity (FIFH) controllers and it can record data from up to six toxic vapor detectors (TVD's) under test and can deliver flows from 5 to 50 liters per minute (L/m) at temperatures from near zero to 50 degrees Celsius (C) using an environmental chamber to maintain the sample temperature. The concentration range for toxic vapors depends on the permeation source installed in the TVG. The PCDAS can provide closed loop control of temperature and humidity to two sample vessels, typically one for zero gas and one for the standard gas. This is required at very low toxic vapor concentrations to minimize the time required to passivate the sample delivery system. Recently, there have been several requests for information about the PCDAS by other laboratories with similar needs, both on and off KSC. The purpose of this paper is to inform the toxic vapor detection community of the current status and planned upgrades to the automated testing of toxic vapor detectors at the Kennedy

  16. Acute toxicity and sublethal effects of the mixture glyphosate (Roundup Active) and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species.

    PubMed

    Henao Muñoz, Liliana Marcela; Montes Rojas, Claudia Marsela; Bernal Bautista, Manuel Hernando

    2015-03-01

    Glyphosate is the most widely used herbicide in the world with application in agriculture, forestry, industrial weed control, garden and aquatic environments. However, its use is highly controversial for the possible impact on not-target organisms, such as amphibians, which are vanishing at an alarming and rapid rate. Due to the high solubility in water and ionic nature, the glyphosate requires of surfactants to increase activity. In addition, for the control of coca (Erythroxylum coca) and agricultural weeds in Colombia, formulated glyphosate is mixed and sprayed with the adjuvant Cosmo-Flux 411F to increase the penetration and activity of the herbicide. This study evaluates the acute toxic and sublethal effects (embryonic development, tadpole body size, tadpole swimming performance) of the mixture of the formulated glyphosate Roundup Active and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species under 96h laboratory standard tests and microcosms, which are more similar to field conditions as they include soil, sand and macrophytes. In the laboratory, embryos and tadpoles of Engystomops pustulosus were the most tolerant (LC50 = 3904 microg a.e./L; LC50=2 799 pg a.e./L, respectively), while embryos and tadpoles of Hypsiboas crepitans (LC50=2 203 microg a.e./L; LC50=1424 microgg a.e./L, respectively) were the most sensitive. R. humboldti and R. marina presented an intermediate toxicity. Embryos were significantly more tolerant to the mixture than tadpoles, which could be likely attributed to the exclusion of chemicals by the embryonic membranes and the lack of organs, such as gills, which are sensitive to surfactants. Sublethal effects were observed for the tadpole body size, but not for the embryonic development and tadpole swimming performance. In microcosms, no toxicity (LC50 could not be estimated), or sublethal responses were observed at concentrations up to fourfold (14.76 kg glyphosate a.e./ha) the highest field application rate of 3

  17. Searching for biomarkers of developmental toxicity with microarrays: normal eye morphogenesis in rodent embryos

    SciTech Connect

    Nemeth, Kimberly A.; Singh, Amar V.; Knudsen, Thomas B. . E-mail: thomas.knudsen@louisville.edu

    2005-08-07

    Gene expression arrays reveal the potential linkage of altered gene expression with specific adverse effects leading to disease phenotypes. But how closely do microarray data reflect early physiological or pharmacological measures that predict toxic event(s)? To explore this issue, we have undertaken experiments in early mouse embryos exposed to various teratogens during neurulation stages with the aim of correlating large-scale changes in gene expression across the critical period during exposure. This study reports some of the large-scale changes in gene expression that can be detected in the optic rudiment of the developing mouse and rat embryo across the window of development during which the eye is exceedingly sensitive to teratogen-induced micro-/anophthalmia. Microarray analysis was performed on RNA from the headfold or ocular region at the optic vesicle and optic cup stages when the ocular primordium is enriched for Pax-6, a master control gene for eye morphogenesis. Statistical selection of differentially regulated genes and various clustering techniques identified groups of genes in upward or downward trajectories in the normal optic primordium during early eye development in mouse and rat species. We identified 165 genes with significant differential expression during eye development, and a smaller subset of 58 genes that showed a tight correlation between mouse-rat development. Significantly over-represented functional categories included fatty acid metabolism (up-regulated) and glycolysis (down-regulated). From studies such as these that benchmark large-scale gene expression during normal embryonic development, we may be able to identify the panel of biomarkers that best correlate with species differences and the risks for developmental toxicity.

  18. Toxicity testing in chemical safety evaluation.

    PubMed

    Bus, James S

    2007-02-01

    The modern era of chemistry has resulted in dramatic improvements in the overall human condition. In addition to new pharmaceuticals, modern chemistry has brought with it enormous health and social benefits Introduction of chemistry-based technologies, however, has also been clearly associated with potential human health risks. The dramatic increase in pharmaceutical and chemical technologies in the post World War II era, coupled with associated examples of demonstrated human toxicity, led to development and application of an expanded and standardized battery of animal and other toxicity tests designed to characterize the potential hazards and risks associated with chemical exposures. This unit discusses the current approach to industrial chemical and pesticide toxicity testing.

  19. Toxicity assessment of TiO₂ nanoparticles in zebrafish embryos under different exposure conditions.

    PubMed

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

    2014-02-01

    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

  20. Effect of Lipid Partitioning on Predictions of Acute Toxicity of Oil Sands Process Affected Water to Embryos of Fathead Minnow (Pimephales promelas).

    PubMed

    Morandi, Garrett D; Zhang, Kun; Wiseman, Steve B; Pereira, Alberto Dos Santos; Martin, Jonathan W; Giesy, John P

    2016-08-16

    Dissolved organic compounds in oil sands process affected water (OSPW) are known to be responsible for most of its toxicity to aquatic organisms, but the complexity of this mixture prevents use of traditional bottom-up approaches for predicting toxicities of mixtures. Therefore, a top-down approach to predict toxicity of the dissolved organic fraction of OSPW was developed and tested. Accurate masses (i.e., m/z) determined by ultrahigh resolution mass spectrometry in negative and positive ionization modes were used to assign empirical chemical formulas to each chemical species in the mixture. For each chemical species, a predictive measure of lipid accumulation was estimated by stir-bar sorptive extraction (SBSE) to poly(dimethyl)siloxane, or by partitioning to solid-supported lipid membranes (SSLM). A narcosis mode of action was assumed and the target-lipid model was used to estimate potencies of mixtures by assuming strict additivity. A model developed using a combination of the SBSE and SSLM lipid partitioning estimates, whereby the accumulation of chemicals to neutral and polar lipids was explicitly considered, was best for predicting empirical values of LC50 in 96-h acute toxicity tests with embryos of fathead minnow (Pimephales promelas). Model predictions were within 4-fold of observed toxicity for 75% of OSPW samples, and within 8.5-fold for all samples tested, which is comparable to the range of interlaboratory variability for in vivo toxicity testing. PMID:27420640

  1. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1.

    PubMed

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-11-05

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels.

  2. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1

    PubMed Central

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-01-01

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels. PMID:26537450

  3. DEVELOPMENTAL TOXICITY OF COPPER CHLORIDE, METHYLENE CHLORIDE,AND 6-AMINONICOTINAMIDE TO EMBRYOS OF THE GRASS SHRIMPPALAEMONETES PUGIO

    EPA Science Inventory

    Embryos of estuarine grass shrimp Palaemonetes pugio have demonstrated sensitivity to various solvents and petroleum products, indicating utility for evaluating estuarine contamination. Testing was performed to establish concentration-response curves for methylene chloride, cop...

  4. Avian models for toxicity testing

    USGS Publications Warehouse

    Hill, E.F.; Hoffman, D.J.

    1984-01-01

    The use of birds as test models in experimental and environmental toxicology as related to health effects is reviewed, and an overview of descriptive tests routinely used in wildlife toxicology is provided. Toxicologic research on birds may be applicable to human health both directly by their use as models for mechanistic and descriptive studies and indirectly as monitors of environmental quality. Topics include the use of birds as models for study of teratogenesis and embryotoxicity, neurotoxicity, behavior, trends of environmental pollution, and for use in predictive wildlife toxicology. Uses of domestic and wild-captured birds are discussed.

  5. Bioequivalence approach for whole effluent toxicity testing

    SciTech Connect

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

    2000-01-01

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

  6. A high-throughput lab-on-a-chip interface for zebrafish embryo tests in drug discovery and ecotoxicology

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    Drug discovery screenings performed on zebrafish embryos mirror with a high level of accuracy. The tests usually performed on mammalian animal models, and the fish embryo toxicity assay (FET) is one of the most promising alternative approaches to acute ecotoxicity testing with adult fish. Notwithstanding this, conventional methods utilising 96-well microtiter plates and manual dispensing of fish embryos are very time-consuming. They rely on laborious and iterative manual pipetting that is a main source of analytical errors and low throughput. In this work, we present development of a miniaturised and high-throughput Lab-on-a-Chip (LOC) platform for automation of FET assays. The 3D high-density LOC array was fabricated in poly-methyl methacrylate (PMMA) transparent thermoplastic using infrared laser micromachining while the off-chip interfaces were fabricated using additive manufacturing processes (FDM and SLA). The system's design facilitates rapid loading and immobilization of a large number of embryos in predefined clusters of traps during continuous microperfusion of drugs/toxins. It has been conceptually designed to seamlessly interface with both upright and inverted fluorescent imaging systems and also to directly interface with conventional microtiter plate readers that accept 96-well plates. We also present proof-of-concept interfacing with a high-speed imaging cytometer Plate RUNNER HD® capable of multispectral image acquisition with resolution of up to 8192 x 8192 pixels and depth of field of about 40 μm. Furthermore, we developed a miniaturized and self-contained analytical device interfaced with a miniaturized USB microscope. This system modification is capable of performing rapid imaging of multiple embryos at a low resolution for drug toxicity analysis.

  7. Individual and joint toxic effects of cadmium sulfate and α-naphthoflavone on the development of zebrafish embryo.

    PubMed

    Yin, Jian; Yang, Jian-ming; Zhang, Feng; Miao, Peng; Lin, Ying; Chen, Ming-li

    2014-09-01

    This paper aims to evaluate the individual and joint toxicities of cadmium sulfate (CdSO4) and α-naphthoflavone (ANF) in zebrafish embryos. As a result, CdSO4 caused both lethal and sub-lethal effects, such as 24 h post-fertilization (hpf) death and 72 hpf delayed hatching. However, ANF only caused sub-lethal effects, including 48 hpf cardiac edema and 72 hpf delayed hatching. Taking 24 hpf death and 48 hpf cardiac edema as endpoints, the toxicities of CdSO4 and ANF were significantly enhanced by each other. Consistently, both CdSO4 and ANF caused significant oxidative stress, including decreases in the reduced glutathione (GSH) level, inhibition of superoxide dismutase (SOD) activity, as well as increases in malondialdehyde (MDA) content in zebrafish embryos, but these mixtures produced much more significant alterations on the biomarkers. Co-treatment of CdSO4 and ANF significantly down-regulated the mRNA level of multidrug resistance-associated protein (mrp) 1 and cytochrome P450 (cyp) 1a, which constituted the protective mechanisms for zebrafish embryos to chemical toxins. In conclusion, co-treatment of CdSO4 and ANF exhibited a much more severe damage in zebrafish embryos than individual treatment. Meanwhile, production of oxidative stress and altered expression of mrp1 and cyp1a could be important components of such joint toxicity.

  8. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    PubMed

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  9. Toxicity of scorpion venom in chick embryo and mealworm assay depending on the use of the soluble fraction versus the whole venom.

    PubMed

    van der Valk, Tom; van der Meijden, Arie

    2014-09-01

    The LD50 is an important metric for venom studies and antivenom development. It has been shown that several variables in the protocol influence the LD50 value obtained, such as venom source, extraction and treatment and administration route. These inconsistencies reduce the utility of the results of these test for comparative studies. In scorpion venom LD50 assays, often only the soluble fraction of the venom is used, whereas other studies use the whole venom. We here tested the toxicity of the soluble fraction in isolation, and of the whole venom in two different systems: chick embryos and mealworms Tenebrio molitor. Ten microliters of venom solutions from Hadrurus arizonensis, Leiurus quinquestriatus, Androctonus australis, Grosphus grandidieri and Heterometrus laoticus were applied to five day old chicken embryos at stage 25-27. Our results showed no significant differences between the LD50 based on the whole venom versus that of only the soluble fraction and in the chicken embryo assay in four of the five scorpion species tested. H. laoticus however, showed a significantly lower LD50 value for the whole venom than the soluble fraction. In assays on mealworms however, this pattern was not seen. Nonetheless, caution may be warranted when using LD50 values obtained from only the soluble fraction. The LD50 values of the five species in this study, based on the chicken embryo assay, showed good correlation with values from the literature based on mouse studies. This suggests that the chick embryo assay may be an economic alternative to rodent assays for scorpion LD50 studies. PMID:24951875

  10. Post-implantation embryo culture: validation with selected compounds for teratogenicity testing.

    PubMed

    Cicurel, L; Schmid, B P

    1988-06-01

    1. Some chemical compounds selected by experts for the validation of in vitro teratogenicity testing were investigated in whole rat embryos cultured during the early stages of organogenesis. All sixteen known in vivo teratogens tested also induced specific malformations in embryos grown in culture. 2. Of the nine compounds which were negative in in vivo rat teratogenicity studies, none provoked dysmorphogenic effects in cultured embryos. Abnormal development of the embryos was only observed with these compounds at concentrations also high enough to affect significantly overall growth and/or differentiation. 3. The results showed a high predictability of this system for the compounds tested and suggest that the post-implantation embryo culture system may also be useful in the prospective testing of new drugs and environmental chemicals.

  11. 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

    Paixao, J.F.; Nascimento, I.A. . E-mail: iracema@ftc.br; Pereira, S.A.; Leite, M.B.L.; Carvalho, G.C.; Silveira, J.S.C.; Reboucas, M.; Matias, G.R.A.; Rodrigues, I.L.P.

    2007-03-15

    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

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

    PubMed

    Paixão, J F; Nascimento, I A; Pereira, S A; Leite, M B L; Carvalho, G C; Silveira, J S C; Rebouças, M; Matias, G R A; Rodrigues, I L P

    2007-03-01

    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 24h, 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

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

    PubMed

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

    2012-09-01

    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.

  14. New Zealand sediment toxicity testing methodologies

    SciTech Connect

    Hickey, C.W.; Roper, D.S.; Nipper, M.; Martin, M.L.

    1995-12-31

    Sediment toxicity testing in New Zealand is developing against a background of an increasing public desire for environmental protection and strict legislative requirements that contaminant discharges should not have any significant adverse effects on aquatic life. The importance of sediment contamination and its potential immediate and long term adverse effects on aquatic biota in general is becoming widely recognized, This has lead to an effort to develop acute and chronic sediment toxicity tests with organisms representative of the New Zealand indigenous biota. An amphipod species occurring in both freshwater and estuarine environments, Chaetocorophium cf lucasi, and the marine bivalve Macomona liliana, a common inhabitant of intertidal sandflats, have been evaluated for their sensitivity to natural sediment characteristics. The amphipod and bivalve are presently being used for testing sediment acute (10d) and chronic toxicity (20--30d), with survival and growth as test endpoints, and the bivalve has shown to be a useful organism for behavioral tests with burial and sediment avoidance by movement and drifting as endpoints. The estuarine bivalve Arthritica bifurca, abundant in muddy sediments, is a self-fertilizing hermaphroditic species and its suitability for sediment tests with a reproductive endpoint is underway. Freshwater sphaeriid bivalves, Sphaerium novazelandiae, are also being used for survival, growth, reproduction and behavioral endpoints. Sensitivity to reference toxicants and results for contaminated sediments will be presented and discussed in relation to sediment quality criteria developed elsewhere.

  15. Acute toxicity and synergism of binary mixtures of antifouling biocides with heavy metals to embryos of sea urchin Glyptocidaris crenularis.

    PubMed

    Xu, Xue; Wang, Xia; Li, Yan; Wang, Yonghua; Wang, Yuan

    2011-08-01

    Acute toxicity and synergism of four antifouling biocides (Irgarol 1051, dichlofluanid, tolylfluanid and Sea-Nine 211) and five heavy metals (Ni, Pb, Zn, Cd and Cu) are investigated using the sea urchin embryos of Glyptocidaris crenularis (G. crenularis) at six typical developmental stages, that is, 2-cell, 4-cell, 8-cell, blastula, gastrula and 4-arm pluteus. Our results show that the toxicity of the four biocides is in an order of Sea-Nine 211 > tolylfluanid > dichlofluanid > Irgarol 1051 and their -log EC(50) values at all stages are strongly linearly correlated with the 1-octanol/water partition coefficient (log P) values (correlation coefficients R > 0.72) indicating the importance of hydrophobicity for the embryonic toxicity. For the five heavy metals, the EC(50) ranges from 0.36 to 30.78 μM and the toxicity follows an order of Cu > Pb > Zn > Cd >Ni. The significant correlation (R > 0.79) between the -log EC50 and the bioconcentration factor (log BCF) values of metals also indicate that the bioaccumulation property of metals contributes to their aquatic toxicity. In addition, the joint effects of the biocides with the heavy metals in embryonic development are assessed by using a concentration addition model. Synergistic effects are observed in almost all 25 mixtures, showing that Cu yields the strongest while Ni the weakest synergistic toxic effects on the embryos development. PMID:20930027

  16. Comparative toxicities of benzene, chlorobenzene, and dichlorobenzenes to sea urchin embryos and sperm

    SciTech Connect

    Pagano, G.; Cipollaro, M.; Corsale, G.; Esposito, A.; Giordano, G.G.; Ragucci, E.; Trieff, N.M.

    1988-04-01

    The leukemogenicity and myelotoxicity of benzene are well-known and the major cause of benzene's banning from most industrial applications. Various benzene derivatives such as alkylbenzenes and chlorobenzenes, however, continue to be used as chemical intermediates, solvents, pesticides, etc. in spite of incomplete knowledge of their chronic toxicity. This study was designed to obtain comparative data on developmental, genetic and reproductive toxicities of benzene (B), chlorobenzene (CB) and dichlorobenzenes (o-, m-, and p-DCB) in the sea urchin bioassay. This test system, permits observation of a number of biological endpoints on mitotic activity, embryogenesis and fertilization, and thus provides multi-parametric toxicological data on xenobiotics.

  17. Toxicity test of a dental commercial composite

    PubMed Central

    Ponce-Bravo, Santa; Martínez-Rivera, José-Luis; Garcés-Ortíz, Maricela

    2015-01-01

    Background International rules must be followed for testing biosecurity in dental materials. A new brand of restorative material appeared in the market and regulations indicated that it should be tested for toxicity. Objectives The aim of this study was to determine the 90-day sub chronic toxicity of one triethylene glycol dimethacrylate containing composite (MEDENTAL Light-Cure Composite™) orally administered to rats according to Organization for Economic Co-Operation and Development no. 48 guidelines and the requirements specified in the ISO 10993-11. Material and Methods Wistar rats ate the polymerized composite during 90 days and were observed to determine changes in their behavior, eye and skin signs and other attitudes such as aggressiveness, posture, walking and response to handling. After 90 days were sacrificed to ascertain blood alterations, we did special hematological tests and assessed microscopic slides from 33 different organs. Results We recorded no significant changes in clinical behavior of the animals. Microscopic review of the H&E stained slides obtained from the analyzed organs showed no abnormal inflammatory or cytological changes and all hematological special tests were within normal limits. Conclusions Results of this study show that under our experimental conditions the MEDENTAL Light-Cure Composite™ does not produce inflammatory or cytological changes suggestive of toxicity. Key words:Dental materials, composite resin, toxicity, inflammation, TEGDMA. PMID:26155348

  18. The role of chemical speciation, chemical fractionation and calcium disruption in manganese-induced developmental toxicity in zebrafish (Danio rerio) embryos.

    PubMed

    Hernández, R B; Nishita, M I; Espósito, B P; Scholz, S; Michalke, B

    2015-10-01

    Manganese (Mn) is an essential nutrient that can be toxic in excess concentrations, especially during early development stages. The mechanisms of Mn toxicity is still unclear, and little information is available regarding the role of Mn speciation and fractionation in toxicology. We aimed to investigate the toxic effects of several chemical forms of Mn in embryos of Danio rerio exposed during different development stages, between 2 and 122h post fertilization. We found a stage-specific increase of lethality associated with hatching and removal of the chorion. Mn(II), ([Mn(H2O)6](2+)) appeared to be the most toxic species to embryos exposed for 48h, and Mn(II) citrate was most toxic to embryos exposed for 72 and/or 120h. Manganese toxicity was associated with calcium disruption, manganese speciation and metal fractionation, including bioaccumulation in tissue, granule fractions, organelles and denaturated proteins.

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

    SciTech Connect

    Becker, M.C.

    1991-05-01

    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.

  20. Contact tests for pentachlorophenol toxicity to earthworms

    SciTech Connect

    Spontak, D.A.

    1994-12-31

    The standardized contact filter paper test (EEC and OECD) provides an effective screening test for toxicity to earthworms in a laboratory setting. A need exists for a reliable and inexpensive technique for non-laboratory settings where screening is desired, but facilities cannot provide for the acquisition and maintenance of the glass vials required by the standardized test. This study evaluated two modifications of the standardized test using clear polyethylene bags, with and without filter paper, with Eisenia fetida and domesticated surface-feeding earthworms. The tests were conducted according to EEC and OECD guidelines. Results of the modified tests corresponded in dose and effect to the standardized contact filter paper test indicating the usefulness of the modified tests.

  1. The developmental toxicity testing of biologics.

    PubMed

    Hazelden, Keith P

    2013-01-01

    The characteristics of biologic drugs, as compared with small molecules, confer significant advantages for both the drug developer and the prospective patients. The necessity for, and the timing of, developmental toxicity testing in the preclinical program must be considered. Choice of an appropriate test system is of particular importance, one that shows pharmacodynamic activity comparable to man. Where the conventional rodent/non-rodent species show such functional cross-reactivity, those species can be used in developmental testing, but often the only relevant species will be a nonhuman primate, in which case an extended study design (the ePPND) should be the default. Such an approach provides appropriate toxicity screening while reducing animal usage.

  2. Acute Toxic Effects of the Herbicide Formulation Focus(®) Ultra on Embryos and Larvae of the Moroccan Painted Frog, Discoglossus scovazzi.

    PubMed

    Wagner, Norman; Lötters, Stefan; Veith, Michael; Viertel, Bruno

    2015-11-01

    For regulatory and scientific purposes, there is a need to understand the sensitivity of a wider variety of wild species of amphibians and the sensitivities within their life stages to chemicals of widespread use such as herbicides. We investigated the acute toxic effects of the herbicide formulation Focus Ultra [with the active ingredient (a.i.) cycloxydim plus solvent naphtha and sodium dioctylsulphosuccinate as added substances] on embryos and early stage larvae of the Moroccan painted frog (Discoglossus scovazzi). Different clinical signs (twitching, convulsion, and narcosis) occurred at 40 and 80 mg/L in embryos (4 and 8 mg a.i./L) and narcotic effects (total immobilization or irregular escape responses) at 10, 15, and 20 mg/L in larvae (1, 1.5, and 2 mg a.i./L). Growth inhibition (total length), starting at 20 mg/L in embryos and 2.5 mg/L in larvae (2 and 0.25 mg a.i./L, respectively) was understood as sign of toxicity (retardation) and not as sign of teratogenicity. However, the connection to teratogenesis remained unclear though total length reduction occurred at concentrations <20 % of the 96-h LC50 value and at a minimum concentration that inhibits growth of only 17 % of the 96-h LC50 value. Starting at 20 mg/L, mortality in embryos significantly increased and at 15 mg/L in early larvae (2 and 1.5 mg a.i./L, respectively). Mortality of larvae was enhanced during the first 24 h of exposure to 15 and 20 mg/L (1.5 and 2 mg a.i./L). Morphology of the embryos remained unobtrusive. In contrary, axial malformations significantly increased in the early larvae starting at 10 mg/L (1 mg a.i./L), a concentration free of lethal effects. In all considered end points, larvae were significantly more sensitive than embryos, probably because of developmental and physiological properties or different exposure and bioavailability of the compound. Focus Ultra induced comparable lethal and immobilization effects in D. scovazzi as it does to standard test

  3. 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.

  4. A model for field toxicity tests

    USGS Publications Warehouse

    Kaiser, Mark S.; Finger, Susan E.

    1996-01-01

    Toxicity tests conducted under field conditions present an interesting challenge for statistical modelling. In contrast to laboratory tests, the concentrations of potential toxicants are not held constant over the test. In addition, the number and identity of toxicants that belong in a model as explanatory factors are not known and must be determined through a model selection process. We present one model to deal with these needs. This model takes the record of mortalities to form a multinomial distribution in which parameters are modelled as products of conditional daily survival probabilities. These conditional probabilities are in turn modelled as logistic functions of the explanatory factors. The model incorporates lagged values of the explanatory factors to deal with changes in the pattern of mortalities over time. The issue of model selection and assessment is approached through the use of generalized information criteria and power divergence goodness-of-fit tests. These model selection criteria are applied in a cross-validation scheme designed to assess the ability of a model to both fit data used in estimation and predict data deleted from the estimation data set. The example presented demonstrates the need for inclusion of lagged values of the explanatory factors and suggests that penalized likelihood criteria may not provide adequate protection against overparameterized models in model selection.

  5. Cardiac toxicity by sublethal 2,3,7,8-tetrachlorodibenzo-p-dioxin correlates with its anti-proliferation effect on cardiomyocytes in zebrafish embryos.

    PubMed

    Chen, Jing

    2015-02-01

    The cardiac toxicity of zebrafish embryos in response to the lethal dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been well characterized. Dioxin contamination levels in nature are usually lower, however, and sublethal TCDD toxicity is less investigated. The present study found that the nonlethal doses of TCDD for 72-h-postfertilization (hpf) zebrafish embryos were 25 pg/mL and lower. For the present study, sublethal TCDD concentrations of 10 pg/mL and 25 pg/mL were selected, and their toxicity was then characterized. The results showed that embryos still exhibited acute and subchronic cardiac toxicity at these 2 dosages. The stroke volume and cardiac output of these embryos significantly declined early until 8 d postexposure. Embryos' heart size became smaller, and the hearts contained fewer cardiomyocytes per heart, with decreased cardiomyocyte proliferation. Apoptosis was not detected either in the TCDD-treated or the control hearts. Real-time polymerase chain reaction (PCR) revealed that the transcription of a battery of cell-cycle-related genes was suppressed within the sublethal TCDD-treated heart. In contrast, embryonic jaw development seemed not to be affected. The present study suggests that dioxin contamination, even at lower levels, might lead to cardiac toxicity in fish embryos. Such cardiac toxicity presents as disrupted normal heart function, originating from the anti-proliferative effect of sublethal TCDD on cardiomyocytes.

  6. Quantitative structure-activity relationships for chronic toxicity of alkyl-chrysenes and alkyl-benz[a]anthracenes to Japanese medaka embryos (Oryzias latipes).

    PubMed

    Lin, Hongkang; Morandi, Garrett D; Brown, R Stephen; Snieckus, Victor; Rantanen, Toni; Jørgensen, Kåre B; Hodson, Peter V

    2015-02-01

    Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are a class of compounds found at significant concentrations in crude oils, and likely the main constituents responsible for the chronic toxicity of oil to fish. Alkyl substituents at different locations on the aromatic rings change the size and shape of PAH molecules, which results in different interactions with tissue receptors and different severities of toxicity. The present study is the first to report the toxicity of several alkylated derivatives of chrysene and benz[a]anthracene to the embryos of Japanese medaka (Oryzias latipes) using the partition controlled delivery (PCD) method of exposure. The PCD method maintained the desired exposure concentrations by equilibrium partitioning of hydrophobic test compounds from polydimethylsiloxane (PDMS) films. Test concentrations declined by only 13% over a period of 17 days. Based on the prevalence of signs of blue sac disease (BSD), as expressed by median effective concentrations (EC50s), benz[a]anthracene (B[a]A) was more toxic than chrysene. Alkylation generally increased toxicity, except at position 2 of B[a]A. Alkyl-PAHs substituted in the middle region had a lower EC50 than those substituted at the distal region. Except for B[a]A and 7-methylbenz[a]anthracene (7-MB), estimated EC50 values were higher than their solubility limits, which resulted in limited toxicity within the range of test concentrations. The regression between log EC50s and logKow values provided a rough estimation of structure-activity relationships for alkyl-PAHs, but Kow alone did not provide a complete explanation of the chronic toxicity of alkyl PAHs.

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

    PubMed

    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

    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.

  8. Mechanisms of Nickel Toxicity in the Highly Sensitive Embryos of the Sea Urchin Evechinus chloroticus, and the Modifying Effects of Natural Organic Matter.

    PubMed

    Blewett, Tamzin A; Smith, D Scott; Wood, Chris M; Glover, Chris N

    2016-02-01

    A 96 h toxicity test showed that the embryos of the New Zealand sea urchin (Evechinus chloroticus) are the most sensitive of all studied marine species to waterborne nickel (Ni), with the EC50 for the development of fully formed pluteus larvae found to be 14 μg L(-1). Failure to develop a standard larval shape suggested skeletal impairment. Whole body ions (Na, Mg) increased with Ni exposure and calcium influx was depressed. The effects of natural organic matter (NOM) on Ni accumulation and toxicity were also examined in three different seawater sources (nearshore, offshore, and near the outlet of a "brown water" stream). At low dissolved organic carbon (DOC) concentrations the brown water NOM was protective against Ni toxicity, however at higher DOC concentrations it exacerbated developmental toxicity in the presence of Ni. These results show that sea urchin development is highly sensitive to Ni via a mechanism that involves ionoregulatory disturbance, and that Ni toxicity is influenced by environmental factors such as NOM. These data will be critical for the development of water quality guidelines for Ni in the marine environment. PMID:26730609

  9. Mechanisms of Nickel Toxicity in the Highly Sensitive Embryos of the Sea Urchin Evechinus chloroticus, and the Modifying Effects of Natural Organic Matter.

    PubMed

    Blewett, Tamzin A; Smith, D Scott; Wood, Chris M; Glover, Chris N

    2016-02-01

    A 96 h toxicity test showed that the embryos of the New Zealand sea urchin (Evechinus chloroticus) are the most sensitive of all studied marine species to waterborne nickel (Ni), with the EC50 for the development of fully formed pluteus larvae found to be 14 μg L(-1). Failure to develop a standard larval shape suggested skeletal impairment. Whole body ions (Na, Mg) increased with Ni exposure and calcium influx was depressed. The effects of natural organic matter (NOM) on Ni accumulation and toxicity were also examined in three different seawater sources (nearshore, offshore, and near the outlet of a "brown water" stream). At low dissolved organic carbon (DOC) concentrations the brown water NOM was protective against Ni toxicity, however at higher DOC concentrations it exacerbated developmental toxicity in the presence of Ni. These results show that sea urchin development is highly sensitive to Ni via a mechanism that involves ionoregulatory disturbance, and that Ni toxicity is influenced by environmental factors such as NOM. These data will be critical for the development of water quality guidelines for Ni in the marine environment.

  10. Ocular Toxicity Testing of Lunar Dust

    NASA Technical Reports Server (NTRS)

    Meyers, Valerie E.

    2010-01-01

    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.

  11. Comparison of toxicity values across zebrafish early life stages and mammalian studies: Implications for chemical testing.

    PubMed

    Ducharme, Nicole A; Reif, David M; Gustafsson, Jan-Ake; Bondesson, Maria

    2015-08-01

    With the high cost and slow pace of toxicity testing in mammals, the vertebrate zebrafish has become a tractable model organism for high throughput toxicity testing. We present here a meta-analysis of 600 chemicals tested for toxicity in zebrafish embryos and larvae. Nineteen aggregated and 57 individual toxicity endpoints were recorded from published studies yielding 2695 unique data points. These data points were compared to lethality and reproductive toxicology endpoints analyzed in rodents and rabbits and to exposure values for humans. We show that although many zebrafish endpoints did not correlate to rodent or rabbit acute toxicity data, zebrafish could be used to accurately predict relative acute toxicity through the rat inhalation, rabbit dermal, and rat oral exposure routes. Ranking of the chemicals based on toxicity and teratogenicity in zebrafish, as well as human exposure levels, revealed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo(a)pyrene, and chlorpyrifos ranked in the top nine of all chemicals for these three categories, and as such should be considered high priority chemicals for testing in higher vertebrates. PMID:25261610

  12. Comparison of toxicity values across zebrafish early life stages and mammalian studies: Implications for chemical testing.

    PubMed

    Ducharme, Nicole A; Reif, David M; Gustafsson, Jan-Ake; Bondesson, Maria

    2015-08-01

    With the high cost and slow pace of toxicity testing in mammals, the vertebrate zebrafish has become a tractable model organism for high throughput toxicity testing. We present here a meta-analysis of 600 chemicals tested for toxicity in zebrafish embryos and larvae. Nineteen aggregated and 57 individual toxicity endpoints were recorded from published studies yielding 2695 unique data points. These data points were compared to lethality and reproductive toxicology endpoints analyzed in rodents and rabbits and to exposure values for humans. We show that although many zebrafish endpoints did not correlate to rodent or rabbit acute toxicity data, zebrafish could be used to accurately predict relative acute toxicity through the rat inhalation, rabbit dermal, and rat oral exposure routes. Ranking of the chemicals based on toxicity and teratogenicity in zebrafish, as well as human exposure levels, revealed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo(a)pyrene, and chlorpyrifos ranked in the top nine of all chemicals for these three categories, and as such should be considered high priority chemicals for testing in higher vertebrates.

  13. In vitro models for liver toxicity testing

    PubMed Central

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

    2013-01-01

    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. PMID:23495363

  14. Standards for reporting fish toxicity tests

    USGS Publications Warehouse

    Cope, O.B.

    1961-01-01

    The growing impetus of studies on fish and pesticides focuses attention on the need for standardized reporting procedures. Good methods have been developed for laboratory and field procedures in testing programs and in statistical features of assay experiments; and improvements are being made on methods of collecting and preserving gish, invertebrates, and other materials exposed to economic poisons. On the other had, the reporting of toxicity data in a compete manner has lagged behind, and today's literature is little improved over yesterday's with regard to completeness and susceptibility to interpretation.

  15. Enantioselectivity in Developmental Toxicity of rac-metalaxyl and R-metalaxyl in Zebrafish (Danio rerio) Embryo.

    PubMed

    Zhang, Yinjun; Zhang, Yi; Chen, An; Zhang, Wei; Chen, Hao; Zhang, Quan

    2016-06-01

    Enantioselectivity of chiral pesticides in environmental safety has attracted more and more attention. In this study, we evaluated the enantioselective toxicity of rac-metalaxyl and R-metalaxyl to zebrafish (Danio rerio) embryos through various malformations including pericardial edema, yolk sac edema, crooked body, and short tails. The results showed that there were significant differences in toxicity to zebrafish embryos caused by rac-metalaxyl and R-metalaxyl, and the LC50 s at 96 h are 416.41 (353.91, 499.29) mg · L(-1) and 320.650 (279.80, 363.46) mg · L(-1) , respectively. In order to explore the possible mechanism of the development defects, the genes involved in the hypothalamic-pituitary-gonadal axis (vtg1, vtg2, cyp17, cyp19a, cyp19b) and hypothalamic-pituitary-thyroid axis (dio1, dio2, nis, tg, tpo) were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). The results revealed that there were no significant differences in the expression of vtg1, vtg2, cyp17, cyp19a, and cyp19b after exposure to rac-metalaxyl. However, the expression of vtg1, cyp19a, and cyp19b decreased significantly after exposure to R-metalaxyl. And likewise, rac-metalaxyl only caused the upregulation of dio2, while R-metalaxyl suppressed the expression of dio1 and tpo and induced the expression of dio2 and nis. The change of gene expression may cause the enantioselectivity in developmental toxicity in zebrafish embryo. The data provided here will be helpful for us to comprehensively understand the potential ecological risks of the currently used chiral fungicides. Chirality 28:489-494, 2016. © 2016 Wiley Periodicals, Inc.

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

    PubMed

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

    2014-06-01

    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.

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

    SciTech Connect

    Park, Jiyeon; Jeters, Robert T.; Gill, Gary A.; Kuo, Li-Jung; Bonheyo, George T.

    2015-10-01

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

  18. 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...

  19. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... test. If the toxicity of the test substance is not already known, a range finding test should be... analyzed. (F) If the measured concentrations of dissolved test substance are considerably lower (e.g., of the test substance.......

  20. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... test. If the toxicity of the test substance is not already known, a range finding test should be... analyzed. (F) If the measured concentrations of dissolved test substance are considerably lower (e.g., of the test substance.......

  1. Developmental toxicity and neurotoxicity of two matrine-type alkaloids, matrine and sophocarpine, in zebrafish (Danio rerio) embryos/larvae.

    PubMed

    Lu, Zhao-Guang; Li, Ming-Hui; Wang, Jun-Song; Wei, Dan-Dan; Liu, Qing-Wang; Kong, Ling-Yi

    2014-08-01

    Matrine and sophocarpine are two major matrine-type alkaloids included in the traditional Chinese medicine (TCM) Kushen (the root of Sophora flavescens Ait.). They have been widely used clinically in China, however with few reports concerning their potential toxicities. This study investigated the developmental toxicity and neurotoxicity of matrine and sophocarpine on zebrafish embryos/larvae from 0 to 96/120h post fertilization (hpf). Both drugs displayed teratogenic and lethal effects with the EC50 and LC50 values at 145 and 240mg/L for matrine and 87.1 and 166mg/L for sophocarpine, respectively. Exposure of matrine and sophocarpine significantly altered spontaneous movement and inhibited swimming performance at concentrations below those causing lethality and malformations, indicating a neurotoxic potential of both drugs. The results are in agreement with most mammalian studies and clinical observations.

  2. Use of the rat postimplantation embryo culture to assess the embryotoxic potency within a chemical category and to identify toxic metabolites.

    PubMed

    Janer, G; Verhoef, A; Gilsing, H D; Piersma, A H

    2008-10-01

    The implementation of in vitro alternatives in the safety evaluation of chemicals in the animal intensive area of reproductive toxicity testing is highly desirable, but has been limited by issues around predictivity and applicability domains. The validation of alternatives may gain from a category approach, in which, rather than validating a test for the universe of chemicals, its predictive value is assessed for each class of chemicals for which the test represents relevant end point(s). We studied the embryotoxicity in rodent postimplantation whole embryo culture (WEC) of a series of phthalates and their metabolites. Phthalate diesters are widely applied industrial chemicals, their monoester derivatives being considered as their embryotoxic metabolites. The relative in vitro potency of three out of four monophthalates was found to mimick that of corresponding diphthalates tested in vivo. The phthalate that deviated from this ranking, monoethylhexylphthalate (MEHP), showed a relatively high in vitro toxicity as compared to in vivo data. This deviation could be explained through kinetic differences among phthalates, as shown between MEHP and monobutylphthalate. In addition, in vitro testing of specific secondary MEHP metabolites showed that they were all less potent than MEHP. This finding confirmed that MEHP in vitro embryotoxicity is most likely the best correlate to DEHP in vivo embryotoxicity. This study shows that a category approach in the assessment of the validation of in vitro alternatives is feasible, and can be improved when kinetic considerations are taken into account.

  3. Use of the rat postimplantation embryo culture to assess the embryotoxic potency within a chemical category and to identify toxic metabolites.

    PubMed

    Janer, G; Verhoef, A; Gilsing, H D; Piersma, A H

    2008-10-01

    The implementation of in vitro alternatives in the safety evaluation of chemicals in the animal intensive area of reproductive toxicity testing is highly desirable, but has been limited by issues around predictivity and applicability domains. The validation of alternatives may gain from a category approach, in which, rather than validating a test for the universe of chemicals, its predictive value is assessed for each class of chemicals for which the test represents relevant end point(s). We studied the embryotoxicity in rodent postimplantation whole embryo culture (WEC) of a series of phthalates and their metabolites. Phthalate diesters are widely applied industrial chemicals, their monoester derivatives being considered as their embryotoxic metabolites. The relative in vitro potency of three out of four monophthalates was found to mimick that of corresponding diphthalates tested in vivo. The phthalate that deviated from this ranking, monoethylhexylphthalate (MEHP), showed a relatively high in vitro toxicity as compared to in vivo data. This deviation could be explained through kinetic differences among phthalates, as shown between MEHP and monobutylphthalate. In addition, in vitro testing of specific secondary MEHP metabolites showed that they were all less potent than MEHP. This finding confirmed that MEHP in vitro embryotoxicity is most likely the best correlate to DEHP in vivo embryotoxicity. This study shows that a category approach in the assessment of the validation of in vitro alternatives is feasible, and can be improved when kinetic considerations are taken into account. PMID:18675337

  4. Paradigm shift in toxicity testing and modeling.

    PubMed

    Sun, Hongmao; Xia, Menghang; Austin, Christopher P; Huang, Ruili

    2012-09-01

    The limitations of traditional toxicity testing characterized by high-cost animal models with low-throughput readouts, inconsistent responses, ethical issues, and extrapolability to humans call for alternative strategies for chemical risk assessment. A new strategy using in vitro human cell-based assays has been designed to identify key toxicity pathways and molecular mechanisms leading to the prediction of an in vivo response. The emergence of quantitative high-throughput screening (qHTS) technology has proved to be an efficient way to decompose complex toxicological end points to specific pathways of targeted organs. In addition, qHTS has made a significant impact on computational toxicology in two aspects. First, the ease of mechanism of action identification brought about by in vitro assays has enhanced the simplicity and effectiveness of machine learning, and second, the high-throughput nature and high reproducibility of qHTS have greatly improved the data quality and increased the quantity of training datasets available for predictive model construction. In this review, the benefits of qHTS routinely used in the US Tox21 program will be highlighted. Quantitative structure-activity relationships models built on traditional in vivo data and new qHTS data will be compared and analyzed. In conjunction with the transition from the pilot phase to the production phase of the Tox21 program, more qHTS data will be made available that will enrich the data pool for predictive toxicology. It is perceivable that new in silico toxicity models based on high-quality qHTS data will achieve unprecedented reliability and robustness, thus becoming a valuable tool for risk assessment and drug discovery.

  5. Acute toxic effects of the herbicide formulation and the active ingredient used in cycloxydim-tolerant maize cultivation on embryos and larvae of the African clawed frog, Xenopus laevis.

    PubMed

    Wagner, Norman; Lötters, Stefan; Veith, Michael; Viertel, Bruno

    2015-04-01

    Most genetically engineered herbicide-tolerant crops are still awaiting approval in Europe. There is, however, a recent trend for the cultivation of cycloxydim-tolerant maize hybrids for use in maize production. We studied the acute toxic effects of the complementary herbicide Focus(®) Ultra and its active ingredient cycloxydim on embryos and early-stage larvae of the African clawed frog (Xenopus laevis). The results indicate that the herbicide formulation is significantly more toxic than the active ingredient alone. Therefore, it is suggested that the added substances either solely or in a synergistic action with the active ingredient are responsible for adverse effects. The formulation was found to be moderately toxic to embryos but highly toxic to early larvae. Based on calculated teratogenic indices, both cycloxydim and Focus(®) Ultra seem to be non-teratogenic and also the minimum Focus(®) Ultra concentration to inhibit growth in embryos and larvae was close to the LC50 values. The data suggest that tests with the rainbow trout are not in all cases appropriate to assess the risk in aquatically developing anurans. This is demonstrated by 96-h LC50 values, which are for rainbow trout more than 50- to 20-fold higher than for early X. laevis larvae. However, based on worst-case predicted environmental concentrations for surface waters, there is apparently a large safety margin in field use of Focus(®) Ultra if buffer strips between the farm land and the amphibian habitats are regarded. PMID:25634323

  6. 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...

  7. 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 ...

  8. A new early life-stage toxicity test using the California grunion (Leuresthes tenuis) and results with chlorpyrifos.

    PubMed

    Goodman, L R; Hansen, D J; Cripe, G M; Middaugh, D P; Moore, J C

    1985-08-01

    California grunion were continuously exposed as embryos and fry to technical chlorpyrifos in two toxicity tests conducted in the same exposure apparatus. The first test, a 35-day early life-stage (ELS) test, began with approximately 2.5-day-old embryos that were exposed in flow-through aquaria in darkness until hatching was stimulated on Day 9 of exposure. The second toxicity test, a fry test, began with newly hatched fry and lasted 26 days. Test water temperature ranged from 23 to 26 degrees C and salinity from 24.5 to 34.0%. Results of the two tests were similar, indicating that exposure of embryos added little to the overall toxicity of chlorpyrifos to grunions. Percentage hatch of embryos was unaffected by the chlorpyrifos concentrations tested. Fry survival was apparently reduced in nominal concentrations greater than or equal to 1.0 micrograms/liter in both tests, but significantly so in concentrations greater than or equal to 1.0 micrograms/liter in the ELS test and greater than or equal to 2.0 micrograms/liter in the fry test. When compared with carrier controls, mean fish weights were significantly reduced in nominal chlorpyrifos concentrations greater than or equal to 0.5 micrograms/liter in the ELS test and greater than or equal to 1.0 micrograms/liter in the fry exposure. Mean bioconcentration factors were 770X for fish that survived the ELS test and 190X for those that survived the fry test. Results demonstrate the practicality of conducting ELS tests for the first time with a marine fish from the Pacific coastal waters of the United States. PMID:2411496

  9. Comparison of bulk sediment and sediment elutriate toxicity testing 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...

  10. EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

    SciTech Connect

    Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

    2012-05-01

    On December 22, 2008, a dike containing fly ash and bottom ash in an 84-acre complex of the Tennessee Valley Authority's (TVA) Kingston Steam Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits extended as far as 4 miles upstream (Emory River mile 6) of the Plant, and some ash was carried as far downstream as Tennessee River mile 564 ({approx}4 miles downstream of the Tennessee River confluence with the Clinch River). A byproduct of coal burning power plants, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be toxic to biological systems. The effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to be the effects of specific ash constituents, especially selenium, on fish early life stages. Uptake by adult female fish of fly ash constituents through the food chain and subsequent maternal transfer of contaminants to the developing eggs is thought to be the primary route of selenium exposure to larval fish (Woock and others 1987, Coyle and others 1993, Lemly 1999, Moscatello and others 2006), but direct contact of the fertilized eggs and developing embryos to ash constituents in river water and sediments is also a potential risk factor (Woock and others 1987, Coyle and others 1993, Jezierska and others 2009). To address the risk of fly ash from the Kingston spill to the reproductive health of downstream fish populations, ORNL has undertaken a series of studies in collaboration with TVA including: (1) a field study of the bioaccumulation of fly ash constituents in fish ovaries and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill; (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (reported in the current

  11. Photoactivated polycyclic aromatic hydrocarbon toxicity in medaka (Oryzias latipes) embryos: relevance to environmental risk in contaminated sites.

    PubMed

    Diamond, Stephen A; Mount, David R; Mattson, Vincent R; Heinis, Larry J; Highland, Terry L; Adams, Andy D; Simcik, Matthew F

    2006-11-01

    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 photoactivated toxicity in medaka (Orvzias latipes) embryos was determined experimentally and then compared with ultraviolet-A (UV-A; 320-400 nm) radiation exposures in a PAH-contaminated field site. The dose metric, J/cm2/ microg fluoranthene/g egg wet weight, provided the means to estimate risk as the depth where the LD50 level would be exceeded at realistic field PAH concentrations, based on estimates of UV-A exposure. The estimates were made using 30 years of solar radiation data for Duluth (MN, USA) and measurements of water-column UV-A transmittance in a PAH-contaminated field site. Medaka embryo failure was strongly related to tissue PAH concentration and UV-A exposure. The LD50 was estimated to be 12.64 J/cm2/ microg fluoranthene/g egg wet weight; the 95% confidence interval was 8.46 to 19.7 J/cm2/microg fluoranthene/g egg wet weight. Embryo failures were characterized by undifferentiated cell proliferation that occurred very early in development. No partial effects or embryo/larval malformations were observed. Estimates of the depth at which the LD50 would be exceeded in the contaminated field site ranged from 10.7 cm (clear-sky conditions and lowest attenuation) to 0.0 cm (cloudy conditions and highest attenuation). Similar calculations were done using water-column attenuation estimates from 12 sites across the Great Lakes (USA). For these, the depths at which the LD50 would be exceeded ranged from 0.00 to 271.6 cm under the conditions described above. These results suggest that PAH phototoxicity may be a risk factor in specific contaminated sites, and they provide a framework for assessing that risk. PMID:17089726

  12. Effect of water hardness on peracetic toxicity to zebrafish, Danio rerio, embryos

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of peracetic acid (PAA) in aquaculture has been suggested as an alternative therapeutic agent as use of previous therapeutants becomes restricted. Few data are available concerning fish toxicity by PAA or factors that affect this toxicity. The aim of this study was to investigate the influ...

  13. Toxicity of glyphosate as Glypro and LI700 to red-eared slider (trachemys scripta elegans) embryos and early hatchlings.

    PubMed

    Sparling, Donald W; Matson, Cole; Bickham, John; Doelling-Brown, Paige

    2006-10-01

    More than 8.2 billion ha of cropland, gardens, and forests are treated with the herbicide glyphosate each year. Whereas the toxicity of glyphosate and associated adjuvants has been measured in other vertebrates, few, if any, studies have looked at their effects in reptiles. In some instances, management of turtle habitat requires control of successional stages through application of herbicides. Adults and juvenile turtles may be exposed directly, whereas embryos may contact the chemicals through the soil. In the present study, we exposed eggs of red-eared sliders (Trachemys scripta elegans) to single applications of herbicide ranging from 0 to 11,206 ppm wet weight of glyphosate in Glypro and 0 to 678 ppm of the surfactant, LI700. Hatching success at the highest concentration was significantly lower (73%) than in other treatments (80-100%). At hatch, turtles at the highest concentration weighed less than those at other concentrations. During a 14-d holding period, we observed dose-response relationships in the ability of hatchlings to right themselves when turned on their backs. At the end of the holding period, hatchlings at the highest dose level were still lighter, and somatic indices were lower, than those in other treatments. Genetic damage, as measured by flow cytometry, increased with treatment concentration except for the highest dose. We conclude that because of the high concentrations needed to produce effects and the protection offered by several centimeters of soil or sediment, glyphosate with LI700 poses low levels of risk to red-eared slider embryos under normal field operations with regards to the endpoints measured in the present study. Carelessness in handling glyphosate or failure to follow label directions may produce adverse effects. There also is a risk that the health of turtle embryos may be affected in ways not measured in the present study.

  14. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    PubMed

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme.

  15. Environmental levels of Zn do not protect embryos from Cu toxicity in three species of amphibians.

    PubMed

    Weir, Scott M; Flynn, R Wesley; Scott, David E; Yu, Shuangying; Lance, Stacey L

    2016-07-01

    Contaminants often occur as mixtures in the environment, but investigations into toxicity usually employ a single chemical. Metal contaminant mixtures from anthropogenic activities such as mining and coal combustion energy are widespread, yet relatively little research has been performed on effects of these mixtures on amphibians. Considering that amphibians tend to be highly sensitive to copper (Cu) and that metal contaminants often occur as mixtures in the environment, it is important to understand the interactive effects that may result from multiple metals. Interactive effects of Cu and zinc (Zn) on amphibians have been reported as antagonistic and, conversely, synergistic. The goal of our study was to investigate the role of Zn in Cu toxicity to amphibians throughout the embryonic developmental period. We also considered maternal effects and population differences by collecting multiple egg masses from contaminated and reference areas for use in four experiments across three species. We performed acute toxicity experiments with Cu concentrations that cause toxicity (10-200 μg/L) in the absence of other contaminants combined with sublethal concentrations of Zn (100 and 1000 μg/L). Our results suggest very few effects of Zn on Cu toxicity at these concentrations of Zn. As has been previously reported, we found that maternal effects and population history had significant influence on Cu toxicity. The explanation for a lack of interaction between Cu and Zn in this experiment is unknown but may be due to the use of sublethal Zn concentrations when previous experiments have used Zn concentrations associated with acute toxicity. Understanding the inconsistency of amphibian Cu/Zn mixture toxicity studies is an important research direction in order to create generalities that can be used to understand risk of contaminant mixtures in the environment. PMID:27086071

  16. Environmental levels of Zn do not protect embryos from Cu toxicity in three species of amphibians.

    PubMed

    Weir, Scott M; Flynn, R Wesley; Scott, David E; Yu, Shuangying; Lance, Stacey L

    2016-07-01

    Contaminants often occur as mixtures in the environment, but investigations into toxicity usually employ a single chemical. Metal contaminant mixtures from anthropogenic activities such as mining and coal combustion energy are widespread, yet relatively little research has been performed on effects of these mixtures on amphibians. Considering that amphibians tend to be highly sensitive to copper (Cu) and that metal contaminants often occur as mixtures in the environment, it is important to understand the interactive effects that may result from multiple metals. Interactive effects of Cu and zinc (Zn) on amphibians have been reported as antagonistic and, conversely, synergistic. The goal of our study was to investigate the role of Zn in Cu toxicity to amphibians throughout the embryonic developmental period. We also considered maternal effects and population differences by collecting multiple egg masses from contaminated and reference areas for use in four experiments across three species. We performed acute toxicity experiments with Cu concentrations that cause toxicity (10-200 μg/L) in the absence of other contaminants combined with sublethal concentrations of Zn (100 and 1000 μg/L). Our results suggest very few effects of Zn on Cu toxicity at these concentrations of Zn. As has been previously reported, we found that maternal effects and population history had significant influence on Cu toxicity. The explanation for a lack of interaction between Cu and Zn in this experiment is unknown but may be due to the use of sublethal Zn concentrations when previous experiments have used Zn concentrations associated with acute toxicity. Understanding the inconsistency of amphibian Cu/Zn mixture toxicity studies is an important research direction in order to create generalities that can be used to understand risk of contaminant mixtures in the environment.

  17. Assessing differences in toxicity and teratogenicity of three phthalates, Diethyl phthalate, Di-n-propyl phthalate, and Di-n-butyl phthalate, using Xenopus laevis embryos.

    PubMed

    Gardner, Steven T; Wood, Andrew T; Lester, Rachel; Onkst, Paitra E; Burnham, Nathaniel; Perygin, Donna H; Rayburn, James

    2016-01-01

    Phthalates, compounds used to add flexibility to plastics, are ubiquitous in the environment. In particular, the diethyl (DEP), di-n-propyl (DnPP), and di-n-butyl (DBP) phthalates were found to exert detrimental effects in both mammalian and non-mammalian studies, with toxic effects varying according to alkyl chain length. Embryos of Xenopus laevis, the African clawed frog, have been used to assess toxicity and teratogenicity of several compounds and serves as a model for assessing adverse and teratogenic effects of ortho-phthalate esters. The purpose of this study was to develop a model for comparison of developmentally toxic effects of ortho-phthalate esters using Xenopus embryos. In this study developing Xenopus laevis embryos were exposed to increasing concentrations of DEP, DnPP, and DBP using the 96-h Frog Embryo Teratogenesis Assay-Xenopus (FETAX), with 96-h lethal concentrations, effective concentrations to induce malformations, teratogenic indices, and concentrations to inhibit growth determined. DEP, DnPP, and DBP showed enhanced toxicity with increasing ester length. Developing Xenopus laevis exposed to DEP, DnPP, and DBP showed similar malformations that also occurred at lower concentrations with increasing alkyl chain length. Teratogenic risk did not change markedly with alkyl chain length, with data showing only DBP to be teratogenic.

  18. Toxicity testing of trinitrotoluene-contaminated soil composts

    SciTech Connect

    Honeycutt, M.E.; McFarland, V.A.; Jarvis, A.S.

    1997-10-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    1996-11-01

    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.

  20. 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 ...

  1. Toxicity of pristine graphene in experiments in a chicken embryo model.

    PubMed

    Sawosz, Ewa; Jaworski, Slawomir; Kutwin, Marta; Hotowy, Anna; Wierzbicki, Mateusz; Grodzik, Marta; Kurantowicz, Natalia; Strojny, Barbara; Lipińska, Ludwika; Chwalibog, André

    2014-01-01

    Evaluation of the potential cytotoxicity of graphene is a key factor for medical applications, where flakes or a surface of graphene may be used as bioactive molecules, drug carriers, or biosensors. In the present work, effects of pristine graphene (pG) on the development of a living organism, with an emphasis on morphological and molecular states of the brain, were investigated using a chicken embryo model. Fertilized chicken eggs were divided into the control group and groups administered with pG suspended in milli-Q water at concentrations of 50 μg/L, 100 μg/L, 500 μg/L, 1,000 μg/L, 5,000 μg/L, and 10,000 μg/L (n=30 per group). The experimental solutions were injected in ovo into the albumin and then the eggs were incubated. After 19 days of incubation, the survival, weight of the body and organs, and blood serum biochemical indices were measured. The brain samples were collected for microscopic examination of brain ultrastructure and measurements of gene and protein expression. Survival of embryos was significantly decreased after treatment with pG, but the body and organ weights as well as biochemical indices were not affected. In all treatment groups, some atypical ultrastructures of the brain were observed, but they were not enhanced by the increasing concentrations of pG. Expression of proliferating cell nuclear antigen at the messenger ribonucleic acid level was downregulated, and the number of proliferating cell nuclear antigen-positive nuclei was significantly reduced in the 500-10,000 μg/L groups compared with the control group, indicating a decreased rate of deoxyribonucleic acid synthesis in the brain. The present results demonstrate some harmful effects of the applied pG flakes on the developing organism, including brain tissue, which ought to be considered prior to any medical applications.

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

    USGS Publications Warehouse

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

    2005-01-01

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

  3. Model validation in aquatic toxicity testing: implications for regulatory practice.

    PubMed

    McCarty, L S

    2012-08-01

    Toxicity test validity is contingent on whether models and assumptions are appropriate and sufficient. A quality control evaluation of the acute toxicity testing protocol using the US. EPA fathead minnow database focused around three key assumptions that ensure results represent valid toxicological metrics: 1, it must be possible to estimate steady-state LC50s; 2, LC50s should occur at equivalent exposure durations; 3, all substantive toxicity modifying factors should be adequately controlled. About 8% of the tests failed the first assumption and are invalid and unusable. Examination of remaining data indicated variance from unquantified effects of toxicity modifying factors remained in LC50s, thereby failing assumption three. Such flaws in toxicity data generated via recommended LC50 testing protocols means resultant data do not represent consistent, comparable measures of relative toxicity. Current regulations employing LC50 testing data are acceptable due to the use of semiquantitative, policy-driven development guidance that considers such data uncertainty. Quantitative applications such as QSARs, mixture toxicity, and regulatory chemical grouping can be compromised. These validation failures justify a formal quality control review of the LC50 toxicity testing protocol. Interim improvements in the design, execution, interpretation, and regulatory applications of LC50 and related protocols using exposure-based dose surrogates are warranted.

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

    NASA Astrophysics Data System (ADS)

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

    2008-10-01

    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.

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

    PubMed

    Lau, Caroline G Y; Marikawa, Yusuke

    2014-11-01

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

  6. On the performance of acute toxicity tests using the National Reference Toxicant Database

    SciTech Connect

    Zaidhk, B.

    1995-12-31

    The US National Reference Toxicant Database was used to compile data from 158 Ceriodaphnia dubia, and 187 fathead minnow acute toxicity tests. The data are analyzed using the EPA flow-chart for acute toxicity tests to determine the distribution of test methods selected. The data are reanalyzed using maximum likelihood estimation assuming probit, logit and Gompertz tolerance distributions and non-parametrically using the Spearman-Karber method with and without trimming. The results of these analyses are compared with respect to mean square error for the parametric methods and confidence intervals for the point estimate for all analyses.

  7. 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...

  8. Exploring waiving opportunities for mammalian acute systemic toxicity tests.

    PubMed

    Graepel, Rabea; Asturiol, David; Prieto, Pilar; Worth, Andrew P

    2016-07-01

    A survey was carried out to explore opportunities for waiving mammalian acute systemic toxicity tests. We were interested in finding out whether data from a sub-acute toxicity test could be used to predict the outcome of an acute systemic toxicity test. The survey was directed at experts in the field of toxicity testing, and was carried out in the context of the upcoming 2018 final registration deadline for chemicals under the EU REACH Regulation. In addition to the survey, a retrospective data analysis of chemicals that had already been registered with the European Chemicals Agency, and for which both acute and sub-acute toxicity data were available, was carried out. This data analysis was focused on chemicals that were administered via the oral route. The answers to the questionnaire showed a willingness to adopt waiving opportunities. In addition, the responses showed that data from a sub-acute toxicity test or dose-range finding study might be useful for predicting chemicals that do not require classification for acute oral toxicity (LD50 > 2000mg/kg body weight). However, with the exception of substances that fall into the non-classified category, it is difficult to predict current acute oral toxicity categories. PMID:27494626

  9. Arsenic (III, V), indium (III), and gallium (III) toxicity to zebrafish embryos using a high-throughput multi-endpoint in vivo developmental and behavioral assay.

    PubMed

    Olivares, Christopher I; Field, Jim A; Simonich, Michael; Tanguay, Robert L; Sierra-Alvarez, Reyes

    2016-04-01

    Gallium arsenide (GaAs), indium gallium arsenide (InGaAs) and other III/V materials are finding increasing application in microelectronic components. The rising demand for III/V-based products is leading to increasing generation of effluents containing ionic species of gallium, indium, and arsenic. The ecotoxicological hazard potential of these streams is unknown. While the toxicology of arsenic is comprehensive, much less is known about the effects of In(III) and Ga(III). The embryonic zebrafish was evaluated for mortality, developmental abnormalities, and photomotor response (PMR) behavior changes associated with exposure to As(III), As(V), Ga(III), and In(III). The As(III) lowest observable effect level (LOEL) for mortality was 500 μM at 24 and 120 h post fertilization (hpf). As(V) exposure was associated with significant mortality at 63 μM. The Ga(III)-citrate LOEL was 113 μM at 24 and 120 hpf. There was no association of significant mortality over the tested range of In(III)-citrate (56-900 μM) or sodium citrate (213-3400 μM) exposures. Only As(V) resulted in significant developmental abnormalities with LOEL of 500 μM. Removal of the chorion prior to As(III) and As(V) exposure was associated with increased incidence of mortality and developmental abnormality suggesting that the chorion may normally attenuate mass uptake of these metals by the embryo. Finally, As(III), As(V), and In(III) caused PMR hypoactivity (49-69% of control PMR) at 900-1000 μM. Overall, our results represent the first characterization of multidimensional toxicity effects of III/V ions in zebrafish embryos helping to fill a significant knowledge gap, particularly in Ga(III) and In(III) toxicology.

  10. Arsenic (III, V), indium (III), and gallium (III) toxicity to zebrafish embryos using a high-throughput multi-endpoint in vivo developmental and behavioral assay.

    PubMed

    Olivares, Christopher I; Field, Jim A; Simonich, Michael; Tanguay, Robert L; Sierra-Alvarez, Reyes

    2016-04-01

    Gallium arsenide (GaAs), indium gallium arsenide (InGaAs) and other III/V materials are finding increasing application in microelectronic components. The rising demand for III/V-based products is leading to increasing generation of effluents containing ionic species of gallium, indium, and arsenic. The ecotoxicological hazard potential of these streams is unknown. While the toxicology of arsenic is comprehensive, much less is known about the effects of In(III) and Ga(III). The embryonic zebrafish was evaluated for mortality, developmental abnormalities, and photomotor response (PMR) behavior changes associated with exposure to As(III), As(V), Ga(III), and In(III). The As(III) lowest observable effect level (LOEL) for mortality was 500 μM at 24 and 120 h post fertilization (hpf). As(V) exposure was associated with significant mortality at 63 μM. The Ga(III)-citrate LOEL was 113 μM at 24 and 120 hpf. There was no association of significant mortality over the tested range of In(III)-citrate (56-900 μM) or sodium citrate (213-3400 μM) exposures. Only As(V) resulted in significant developmental abnormalities with LOEL of 500 μM. Removal of the chorion prior to As(III) and As(V) exposure was associated with increased incidence of mortality and developmental abnormality suggesting that the chorion may normally attenuate mass uptake of these metals by the embryo. Finally, As(III), As(V), and In(III) caused PMR hypoactivity (49-69% of control PMR) at 900-1000 μM. Overall, our results represent the first characterization of multidimensional toxicity effects of III/V ions in zebrafish embryos helping to fill a significant knowledge gap, particularly in Ga(III) and In(III) toxicology. PMID:26824274

  11. Sensitivity or artifact? -- IQ Toxicity Test -- effluent values

    SciTech Connect

    Hayes, K.R.; Novotny, A.N.; Batista, N.

    1995-12-31

    Several complex effluents were DAPHNIA MAGNA IQ TOXICITY TESTED -- (1.25 hours) and conventionally tested with Daphnia magna (48 hours). In many samples the IQ Technology yielded low EC50 values while the 48 hour exposures yielded no acute toxicity. Possible explanations have been suggested for this occurrence such as: genotoxicity, mutagenicity, substrate interference, and enzyme satiation. To identify the causative agent(s) of this response a Toxicity Identification Evaluation was performed on one of the samples. To define the nature of the response, THE SOS-CHROMOTEST KIT and THE MUTA-CHROMOPLATE KIT were utilized to characterize genotoxicity and mutagenicity respectively. The sample did not test positive for genotoxicity but tested positive for mutagenicity only after activation with S9 enzymes, suggesting the presence of promutagens. Additional work needs to be performed to correlate IQ TOXICITY TEST sensitivity with positive MUTA-CHROMOPLATE response.

  12. Incorporation of a subacute test with zebra fish into a hierarchical system for evaluating the effect of toxicants in the aquatic environment

    SciTech Connect

    Neilson, A.H.; Allard, A.S.; Fischer, S.; Malmberg, M.; Viktor, T. )

    1990-08-01

    Single-species laboratory tests were used to assess the acute toxicity of halogenated phenolic compounds. No single test system was most sensitive to all of the compounds examined, substantial variations in the sensitivity of the various organisms were noted, and there was no correlation between the toxicities assayed with different test systems. The zebra fish (Brachydanio rerio) embryo/larvae system was used to examine subacute effects using two of the compounds, and a protocol was developed with 6 weeks preexposure to the toxicant. Preexposure decreased the lowest observable effect concentration by a factor of about 4, and the effect was completely reversible during a 6-week postexposure period in the absence of the toxicant. An enclosed system for carrying out the zebra fish embryo/larvae test was developed and evaluated with three neutral volatile compounds: the median survival time and the frequency of occurrence of deformation were examined as end points. The effect of pH on toxicity was evaluated in buffered media for four of the test systems: toxicity increased markedly at the lower pH values, and it could be shown that the ionized forms of the phenols were not the only contributors to toxicity. It is proposed that the zebra fish system incorporating preexposure could be incorporated into a hierarchical system using a range of organisms for assessing acute toxicity in single species under laboratory conditions and multicomponent systems simulating natural ecosystems.

  13. Reference toxicants for toxicity testing using Caenorhabditis elegans in aquatic media

    SciTech Connect

    Cressman, C.P. III; Williams, P.L.

    1997-09-01

    Caenorhabditis elegans aquatic toxicity assays were standardized with five common reference toxicants: CdCl{sub 2}, NaCl, KCl, sodium lauryl sulfate (SLS), and sodium pentachlorophenate (PCP). Aquatic toxicity testing was conducted in 3 media: a standard C. elegans medium; EPA moderately hard reconstituted water; and EPA moderately hard mineral water. Test duration in each medium was 24h without a food source, and 24h and 48h with Escherichia coli strain OP50 as a food source. Each test was replicated three times with each replicate having 6 wells per concentration, 10 worms per well. LC{sub 50} values were calculated using probit analysis. The average LC{sub 50}s for each set of replications were compared to assess sensitivity and reproducibility of the data, identifying expected variation between replicate tests. These reference toxicants increase the database for C. elegans and provide a benchmark for further application.

  14. Evaluation of new aquatic toxicity test methods for oil dispersants

    SciTech Connect

    Pace, C.B.; Clark, J.R.; Bragin, G.E.

    1994-12-31

    Current aquatic toxicity test methods used for dispersant registration do not address real world exposure scenarios. Current test methods require 48 or 96 hour constant exposure conditions. In contrast, environmentally realistic exposures can be described as a pulse in which the initial concentration declines over time. Recent research using a specially designed testing apparatus (the California system) has demonstrated that exposure to Corexit 9527{reg_sign} under pulsed exposure conditions may be 3 to 22 times less toxic compared to continuous exposure scenarios. The objectives of this study were to compare results of toxicity tests using the California test system to results from standardized tests, evaluate sensitivity of regional (Holmesimysis cast and Atherinops affinis) vs. standard test species (Mysidopsis bahia and Menidia beryllina) and determine if tests using the California test system and method are reproducible. All tests were conducted using Corexit 9527{reg_sign} as the test material. Standard toxicity tests conducted with M. bahia and H. cast resulted in LC50s similar to those from tests using the California apparatus. LC50s from tests conducted in the authors` laboratory with the California system and standard test species were within a factor of 2 to 6 of data previously reported for west coast species. Results of tests conducted with H. cast in the laboratory compared favorably to data reported by Singer et al. 1991.

  15. Rapid toxicity testing based on yeast respiratory activity

    SciTech Connect

    Haubenstricker, M.E. ); Meier, P.G.; Mancy, K.H. ); Brabec, M.J. )

    1990-05-01

    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.

  16. Short-term algal toxicity test based on phosphate uptake.

    PubMed

    Kaneko, H Hidehiro; Shimada, Akiko; Hirayama, Kimiaki

    2004-04-01

    In order to develop a short-term algal toxicity test, the growth of and the phosphate uptake by the green alga Selenastrum capricornutum during batch culture were observed. In the control medium, S. capricornutum took up phosphate earlier than it grew. It was also observed that the phosphate uptake was inhibited by the presence of a toxicant. From these results, phosphate uptake was considered as one of the useful effect parameters for a short-term algal toxicity test. As the removal rate of phosphate from the medium is a function of the amount of algal cell initially inoculated, the test period is variable. The relationship between the amount of inoculation and phosphate uptake was examined and the test conditions suitable for a 3-h toxicity test were established as one example. According to this test procedure, the inhibitory effect of some toxicants on the phosphate uptake was determined. For comparison, a conventional algal assay based on algal growth was also performed. The EC50s for both tests were close. This indicated that the algal toxicity test method proposed in this paper would be useful for the uses where rapidity is required. PMID:15087199

  17. Marine and estuarine porewater toxicity testing -- species and end point comparisons

    SciTech Connect

    Carr, R.S.; Chapman, D.C.; Biedenbach, J.M.; Robertson, L.

    1994-12-31

    As part of their continuing development and evaluation of the porewater toxicity test approach for assessing the quality of marine and estuarine sediments, a variety of studies involving species and endpoint comparisons as well as validation studies have recently been conducted. The results from numerous extensive sediment quality assessment surveys have demonstrated that porewater toxicity tests are considerably more sensitive than the standard solid-phase tests and invariably exhibit a higher degree of concordance with sediment quality assessment guidelines than the standard tests. Species that have been evaluated for use in testing marine and estuarine pore water include a life-cycle test with the polychaete Dinophilus gyrociliatus, survival and hatching success with embryo-larval stages of red drum Sciaaenops ocellatus, survival of nauplii stages of the harpacticoid copepod Longipedia sp., and three different assays (fertilization, embryological development, and cytogenetic) with the sea urchin Arbacia punctulata. The different species and end points have been compared using sediment pore water from a variety of contaminated sites. Although the results of tests with the different species and end points were often comparable, in general, the sea urchin embryological development assay appears to be the most sensitive porewater test evaluated thus far in their laboratory.

  18. Ameliorative effects of sodium chloride on acute copper toxicity among Cope's gray tree frog (Hyla chrysoscelis) and green frog (Rana clamitans) embryos.

    PubMed

    Brown, Maria G; Dobbs, Emily K; Snodgrass, Joel W; Ownby, David R

    2012-04-01

    Urban stormwater runoff is composed of a mixture of components, including polycyclic aromatic hydrocarbons, metals, deicing agents, and many others. The fate of these chemicals is often in stormwater detention ponds that are used by amphibians for breeding. Among aquatic organisms, the toxic mechanism for many metals involves interference with active Na(+) and Cl(-) uptake. Addition of cations has been shown to reduce the toxicity of metals among some aquatic organisms through competitive inhibition, but no studies have investigated the interaction between NaCl and Cu among amphibian embryos and larvae. To determine the degree to which NaCl may ameliorate the toxicity of Cu to amphibian embryos and larvae, the authors exposed Hyla chrysoscelis (Cope's gray treefrogs) and Rana (Lithobates) clamitans (green frogs) to seven levels of Cu and NaCl in fully factorial experiments. When exposure was in artificial hard water, Cu was highly toxic to both species (96-h median lethal concentration [LC50] of 44.7 µg/L and 162.6 µg/L for H. chrysoscelis and R. clamitans, respectively). However, approximately 500 mg/L of NaCl eliminated Cu toxicity over the range of Cu concentrations used in the experiments (maximum 150 µg Cu/L for H. chrysoscelis and 325 µg Cu/L for R. clamitans). The current results suggest that NaCl is likely responsible for the toxic effects of NaCl and metal mixtures that might be typical of runoff from road surfaces in northern latitudes.

  19. The Nicotine-Evoked Locomotor Response: A Behavioral Paradigm for Toxicity Screening in Zebrafish (Danio rerio) Embryos and Eleutheroembryos Exposed to Methylmercury

    PubMed Central

    Mora-Zamorano, Francisco X.; Svoboda, Kurt R.; Carvan, Michael J.

    2016-01-01

    This study is an adaptation of the nicotine-evoked locomotor response (NLR) assay, which was originally utilized for phenotype-based neurotoxicity screening in zebrafish embryos. Zebrafish embryos do not exhibit spontaneous swimming until roughly 4 days post-fertilization (dpf), however, a robust swimming response can be induced as early as 36 hours post-fertilization (hpf) by means of acute nicotine exposure (30–240μM). Here, the NLR was tested as a tool for early detection of locomotor phenotypes in 36, 48 and 72 hpf mutant zebrafish embryos of the non-touch-responsive maco strain; this assay successfully discriminated mutant embryos from their non-mutant siblings. Then, methylmercury (MeHg) was used as a proof-of-concept neurotoxicant to test the effectiveness of the NLR assay as a screening tool in toxicology. The locomotor effects of MeHg were evaluated in 6 dpf wild type eleutheroembryos exposed to waterborne MeHg (0, 0.01, 0.03 and 0.1μM). Afterwards, the NLR assay was tested in 48 hpf embryos subjected to the same MeHg exposure regimes. Embryos exposed to 0.01 and 0.03μM of MeHg exhibited significant increases in locomotion in both scenarios. These findings suggest that similar locomotor phenotypes observed in free swimming fish can be detected as early as 48 hpf, when locomotion is induced with nicotine. PMID:27123921

  20. THE TOXCAST PROGRAM FOR PRIORITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    The United States Environmental Protection Agency (EPA) is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals...

  1. Enzyme biosynthesis in bacteria as a basis for toxicity testing

    SciTech Connect

    Dutton, R.J.

    1988-01-01

    An assay based on the inhibition of {beta}-galactosidase biosynthesis was compared to a similar assay based on the inhibition of {beta}-galactosidase activity. In both test, Escherichia coli were induced to synthesize {beta}-galactosidase by exposure to isopropyl-{beta}-thiogalactoside (IPTG). The induction step preceded contact of the cells with toxic chemicals in the enzyme activity assay, whereas in the enzyme biosynthesis test, IPTG was added following contact of cells with the toxicant. Relative sensitivity was judged on the basis of responses to heavy metals and organic toxicants of environmental importance. Comparison of these results to median inhibitory concentration data (IC50s) achieved with other microbial systems, Daphnia bioassay, and fish bioassay indicate that the enzyme activity test was sensitive to heavy metals, but was insensitive to organic toxicants. The test based on inhibition of {beta}-galactosidase biosynthesis was sensitive to both heavy metals and organics.

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

    SciTech Connect

    Bitton, G.; Koopman, B. )

    1992-01-01

    Microbioassays using bacteria or enzymes are increasingly applied to measure chemical toxicity in the environment. Attractive features of these assays may include low cost, rapid response to toxicants, high sample throughput, modest laboratory equipment and space requirements, low sample volume, portability, and reproducible responses. Enzymatic tests rely on measurement of either enzyme activity or enzyme biosynthesis. Dehydrogenases are the enzymes most used in toxicity testing. Assay of dehydrogenase activity is conveniently carried out using oxidoreduction dyes such as tetrazolium salts. Other enzyme activity tests utilize ATPases, esterases, phosphatases, urease, luciferase, beta-galactosidase, protease, amylase, or beta-glucosidase. Recently, the inhibition of enzyme (beta-galactosidase, tryptophanase, alpha-glucosidase) biosynthesis has been explored as a basis for toxicity testing. Enzyme biosynthesis was found to be generally more sensitive to organic chemicals than enzyme activity.107 references.

  3. 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.

  4. Neutral red uptake cytotoxicity tests for estimating starting doses for acute oral toxicity tests.

    PubMed

    Stokes, William S; Casati, Silvia; Strickland, Judy; Paris, Michael

    2008-05-01

    In vitro cytotoxicity assays can be used as alternative toxicity tests to reduce the total number of animals needed for acute oral toxicity tests. This unit describes two methods for determining the in vitro cytotoxicity of test substances using neutral red uptake (NRU) and using the in vitro data to determine starting doses for in vivo acute oral systemic toxicity tests, e.g., the up-and-down procedure or the acute toxic class method. The use of the NRU methods to determine starting doses for acute oral toxicity tests may reduce the number of animals required, and for relatively toxic substances, this approach may also reduce the number of animals that die or require humane euthanasia due to severe toxicity. An interlaboratory validation study has demonstrated that the methods are useful and reproducible for these purposes. Two standardized protocols provide details for performing NRU tests with rodent and human cells.

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

    PubMed

    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

    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.

  6. In vitro testing for lung toxicity.

    PubMed

    Ciabattoni, G; Montuschi, P; Curró, D; Preziosi, P

    1993-09-01

    We characterized the pattern of arachidonic acid metabolites released from sensitized isolated guinea pig lungs undergoing anaphylactic reactions after ovalbumin challenge. TXB(2) (the stable hydrolysis product of (TXA(2)) is the most abundant product: it was released at an average of 13.7 +/- 7.0 ng/min (+/-SD, n = 33) during the anaphylactic reaction (i.e. a five- to six-fold increase in comparison with the basal release). Its level correlates with both the bronchoconstrictor response and LTC(4) and LTB(4) release. In non-sensitized lungs the release of basal TXB(2) increased about five-fold during a 10-min exposure to a formaldehyde aerosol at the dose of 10 ppm; this increase was concomitant with an 87.5 +/- 10.0% (+/-SD) reduction of the tracing recording the pressure-volume variations in the lung. No change in the release of lipoxygenase products was observed after exposure to formaldehyde aerosol. Pre-treatment with N-acetylcysteine (10(-3)-10(-4)m) reduced both formaldehyde-induced bronchoconstriction and the increase of TXB(2) release. An acid-water aerosol, resembling the composition of acid rain, strongly increased TXB(2) release in the pH range 4.5 to 2.5, without affecting the lipoxygenase pathway of arachidonic acid metabolism. These data suggest that exposure to toxicants that irritate the respiratory tract selectively enhances TXB(2) release, while an antigen challenge stimulates both the cyclooxygenase and lipoxygenase pathways of lung arachidonate metabolism. Thus, the different pattern of arachidonic acid cascade activation may predict a direct toxic effect or an allergic reaction when the xenobiotic is injected into the pulmonary artery or administered by way of inhalation as an aerosol. More recently vasoactive intestinal polypeptide (VIP) has been proposed as a modulator of lung inflammation and airway constriction. In sensitized lungs the antigen challenge induced a five-fold increase in VIP release, coinciding with the increase of

  7. Developmental toxicity of p,p'-dichlorodiphenyltrichloroethane, 2,4,6-trinitrotoluene, their metabolites, and benzo[a]pyrene in Xenopus laevis embryos.

    PubMed

    Saka, Masahiro

    2004-04-01

    Since 1995, high incidences of deformed frogs have been documented in Kitakyushu, Japan. In this area, relatively high concentrations of DDT, trinitrotoluene (TNT), their metabolites (p,p'-dichlorodiphenyldichloroethylene [DDE], p,p'-dichlorodiphenyldichloroethane [DDD], 2-amino-4,6-dinitrotoluene [2ADNT], and 4-amino-2,6-dinitrotoluene [4ADNT]), and benzo[a]pyrene [BaP]) have been identified from field samples. I used a standardized assay with Xenopus laevis embryos (frog embryo teratogenesis assay--Xenopus, FETAX) to examine the developmental toxicity of these compounds. Both DDE and BaP were considered nearly nontoxic in embryonic development because they induced low (< 10%) mortality and malformation incidence even at the highest concentrations tested (DDE, 393 microM; BaP, 13.2 microM). The DDD (96-h median lethal concentration [LC50] = 44.1 microM, 96-h median effective concentration [EC50] for malformation = 14.9 microM) was more lethal and teratogenic than its parent compound, DDT (96-h LC50 = 101 microM, 96-h EC50 = 41.5 microM). Predominant symptoms observed were axial malformations (DDT and DDD) and irregular gut coiling (DDT). However, DDT and DDD should not act as major lethal or teratogenic toxicants in the aquatic environment within a short-term exposure via water because their 96-h LC50 and 96-h EC50 values were extremely high, considering their low solubility in water. The TNT (96-h LC50 = 16.7 microM) was more lethal than 2ADNT (96-h LC50 = 166 microM) or 4ADNT (96-h LC50 = 115 microM). Although 4ADNT (96-h EC50 = 85.8 microM) induced various tadpole malformations, it was a weak teratogen compared with TNT (96-h EC50 = 9.78 microM) and 2ADNT (96-h EC50 = 16.9 microM). The most typical malformations observed were axial malformations, eye abnormalities (TNT), edema, and irregular gut coiling (2ADNT and 4ADNT). The 96-h LC50 and 96-h EC50 values of TNT, 2ADNT, and 4ADNT were lower than their saturated concentrations in water. Therefore, these

  8. Rice seed toxicity tests for organic and inorganic substances.

    PubMed

    Wang, W

    1994-01-01

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

  9. Rice seed toxicity tests for organic and inorganic substances

    USGS Publications Warehouse

    Wang, W.

    1994-01-01

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

  10. Harmonization of standard toxicity test methods used in North America

    SciTech Connect

    Ingersoll, C.G.; Dwyer, F.J.; Ankley, G.T.

    1995-12-31

    Over the past two years, Environment Canada (EC) and the US Environmental Protection Agency (EPA) have developed standard methods for conducting toxicity and bioaccumulation tests with freshwater, estuarine, and marine sediments. Existing ASTM methods were used as a basis to harmonize these methods for conducting testing with either field-collected or laboratory-spiked sediments. For freshwater toxicity tests, methods are described by EC and EPA for the amphipod Hyalella azteca and the midges Chironomus tentans and C. riparius. Endpoints include 10- to 14-d survival of growth. Methods are also described by EPA for conducting 28-d bioaccumulation tests with the oligochaete Lumbriculus variegatus. For estuarine and marine toxicity tests, methods are described for several amphipods (i.e., Rhepoxynius abronius, Ampelisca abdita, Eohaustorius estuarius, Leptocheirus plumulosus). Endpoints include 10-d survival and reburial. EC is also developing methods for conducting toxicity tests with Atlantic, Pacific, and Arctic Canadian species of polychaetes. Methods are described by EPA for conducting 28-d bioaccumulation tests with a variety of mollusks (i.e., Macoma spp.) and polychaetes (i.e., Nereis spp.). Slight inconsistencies in methods between freshwater and estuarine/marine testing or between EC and EPA testing include: (1) static vs. flow-through conditions, (2) sieving of sediment, (3) types and quantity of food, (4) age of test organisms, or (4) duration of the test and required endpoints. Additional research is in progress to: (1) develop chronic toxicity tests with amphipods and midges measuring survival, growth, or reproduction, (2) develop whole-sediment toxicity identification evaluation (TIE) procedures, (3) refine sediment spiking procedures, and (4) field-validate laboratory tests.

  11. Validation test with embryonic and larval stages of Chordodes nobilii (Gordiida, Nematomorpha): sensitivity to three reference toxicants.

    PubMed

    Achiorno, Cecilia L; de Villalobos, Cristina; Ferrari, Lucrecia

    2010-09-01

    Chordodes nobilii is a parasite whose pre- and postparasitic stages are found in different types of freshwater bodies. Due to the peculiarities of its life cycle, it acts as a link between freshwater bodies and terrestrial ecosystems. There is little toxicological information on the group Gordiida. It is only known that embryos and larvae of C. nobilii are sensitive to glyphosate and malathion at relevant concentrations in the environment. On this basis, the aims of this study were to characterize the sensitivity of the pre-parasitic stages of C. nobilii to three reference toxicants: sodium dodecyl sulfate (SDS), cadmium chloride and potassium dichromate (Cr(6+)), and to validate a previous experimental protocol for ecotoxicological risk assessment. The protocol involved acute exposure of early embryonic stages and larvae to the three toxicants for 96 h and 48 h, respectively. Embryo development was inhibited only by Cr(6+) which presented a IC(50) of 0.71 mg Cr(6+)L(-1). The development of the eggs exposed to SDS and those exposed to cadmium chloride showed no differences as compared to that of controls. However, the infective capacity of larvae derived from the eggs exposed to the three toxicants was lower than that of controls. Larval survival was affected even at the lowest concentration of the three toxicants assayed. In relation to other freshwater organisms, C. nobilii can be characterized as an organism medium to highly sensitive to the toxicants tested.

  12. Predictive modeling of developmental toxicity using EPA’s Virtual Embryo

    EPA Science Inventory

    Standard practice in prenatal developmental toxicology involves testing chemicals in pregnant laboratory animals of two species, typically rats and rabbits, exposed during organogenesis and evaluating for fetal growth retardation, structural malformations, and prenatal death just...

  13. A New Toxicity Test Using the Freshwater Copepod Cyclops vernalis.

    PubMed

    Marus, Emma M; Elphick, James R; Bailey, Howard C

    2015-09-01

    The cladocerans Ceriodaphnia dubia and Daphnia magna are widely used in environmental toxicity testing and the test methodologies for these species are well developed. However, copepods are a much more abundant contributor to zooplankton in many lakes, but they are not routinely used in toxicity tests. Therefore, we propose toxicity test methods for the freshwater copepod, Cyclops vernalis assessing effects on its survival and growth. A case study is presented in which the proposed test was performed with a range of concentrations of total dissolved solids (TDS) and used as part of a test battery to develop a site-specific water quality objective. C. vernalis was less sensitive to TDS compared to D. magna and C. dubia, but similarly sensitive to an alga, a diatom, a rotifer, a chironomid, and two fish species. No adverse effects were observed on survival or growth of C. vernalis at TDS concentrations up to 1500 mg/L. PMID:26183385

  14. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for asexual (parthenogenic) reproduction. For automatic feeding devices, a suggested rate is 5 to 7 mg... cultured to produce test organisms through reproduction. (2) Chronic toxicity test means a method used to... an extended period of time. In this test guideline, mortality and reproduction (and...

  15. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for asexual (parthenogenic) reproduction. For automatic feeding devices, a suggested rate is 5 to 7 mg... cultured to produce test organisms through reproduction. (2) Chronic toxicity test means a method used to... an extended period of time. In this test guideline, mortality and reproduction (and...

  16. 76 FR 38169 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-29

    ... AGENCY Toxic Substances Control Act Chemical Testing; Receipt of Test Data AGENCY: Environmental... chemicals listed in the Toxic Substances Control Act (TSCA) section 4 test rule titled ``In Vitro Dermal Absorption Rate Testing of Certain Chemicals of Interest to the Occupational Safety and Health...

  17. Interpretation of coastal sediment quality based on trace metal and PAH analysis, benthic foraminifera, and toxicity tests (Sardinia, Western Mediterranean).

    PubMed

    Schintu, Marco; Buosi, Carla; Galgani, François; Marrucci, Alessandro; Marras, Barbara; Ibba, Angelo; Cherchi, Antonietta

    2015-05-15

    An integrated approach for the assessment of coastal sediment quality was utilised in three areas of Sardinia (Western Mediterranean, Italy). Sediments were analysed for trace metals and polycyclic aromatic hydrocarbons (PAHs), while benthic foraminifera were used as bioindicators. Furthermore, the embryo-toxicity test was used to provide ecologically relevant information using rapid and cost-effective screening tools. The aim was to evaluate the usefulness of coupling different analytical tools. The results revealed the presence of polluted sediments in areas exposed to petrochemical industries, smelters or military settlements. However, while foraminifera have presented similar indications for chemical analysis of contamination levels in the different areas, the toxicity test exhibited a poor relationship with the contaminants measured individually. The results raise questions concerning the bioavailability of contaminants released by sediments in the water column. Overall, the toxicity rate was significant in many samples in comparison with other sites studied in other Mediterranean regions. PMID:25795553

  18. A new biological test of water toxicity-yeast Saccharomyces cerevisiae conductometric test.

    PubMed

    Dolezalova, Jaroslava; Rumlova, Lubomira

    2014-11-01

    This new biological test of water toxicity is based on monitoring of specific conductivity changes of yeast Saccharomyces cerevisiae suspension as a result of yeast fermentation activity inhibition in toxic conditions. The test was verified on ten substances with various mechanisms of toxic effect and the results were compared with two standard toxicity tests based on Daphnia magna mobility inhibition (EN ISO 6341) and Vibrio fischeri bioluminescence inhibition (EN ISO 11348-2) and with the results of the S. cerevisiae lethal test (Rumlova and Dolezalova, 2012). The new biological test - S. cerevisiae conductometric test - is an express method developed primarily for field conditions. It is applicable in case of need of immediate information about water toxicity. Fast completion is an advantage of this test (time necessary for test completion is about 60min), the test is simple and the test organism - dried instant yeast - belongs among its biggest advantages because of its long-term storage life and broad availability.

  19. Economical test methods for developmental neurobehavioral toxicity.

    PubMed

    Bignami, G

    1996-04-01

    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.

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

    SciTech Connect

    Yeardley, R.B. Jr.; Lazorchak, J.M.; Pence, M.A.

    1995-07-01

    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.

  1. A COMPARISON OF BULK SEDIMENT TOXICITY TESTING METHODS AND SEDIMENT ELUTRIATE TOXICITY

    EPA Science Inventory

    Bulk sediment toxicity tests are routinely used to assess the level and extent of contamination in natural sediments. While reliable, these tests can be resource intensive, requiring significant outlays of time and materials. The purpose of this study was to compare the results ...

  2. Oral Toxicity Study and Skin Sensitization Test of a Cricket

    PubMed Central

    Ryu, Hyeon Yeol; Lee, Somin; Ahn, Kyu Sup; Kim, Hye Jin; Lee, Sang Sik; Ko, Hyuk Ju; Lee, Jin Kyu; Cho, Myung-Haing; Ahn, Mi Young; Kim, Eun Mi; Lim, Jeong Ho; Song, Kyung Seuk

    2016-01-01

    Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource. PMID:27123167

  3. 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...

  4. Acute systemic toxicity--prospects for tiered testing strategies.

    PubMed

    Botham, P A

    2004-04-01

    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 more importantly to increase their regulatory acceptance. They can now be used within a strategy for acute toxicity testing for all types of test substances and for all regulatory and in-house purposes. In vitro cytotoxicity tests could be used as adjuncts to these alternative animal tests within the next year or so to improve dose level selection and thus give further modest improvements in the numbers of animals used. However, the total replacement of animal tests requires a considerable amount of further test development, followed by validation, and is at least 10 years away.

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

    PubMed

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

    2003-01-01

    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

  6. An invertebrate embryo test with the apple snail Marisa cornuarietis to assess effects of potential developmental and endocrine disruptors.

    PubMed

    Schirling, M; Bohlen, A; Triebskorn, R; Köhler, H-R

    2006-09-01

    A novel invertebrate embryo test with the apple snail, Marisa cornuarietis, comprising a test protocol for the following developmental endpoints is described: formation of eyes and tentacles, heart rate, hatching, weight after hatching. To evaluate effects on embryonic development, the snails were treated in a first step with 250 or 500 microg/l cadmium. Sublethal effects in terms of a significant delay in hatching could be found in the 250 microg/l treated animals, whereas 500 microg/l Cd were lethal for the snail embryos. To test endocrine disrupting chemicals with this protocol, experiments with bisphenol A (50 microg/l, 100 microg/l) and 17alpha-ethinylestradiol (10 microg/l) were performed. In both treatments an increase of weight after hatching was observed as well as a significant decline in the heart rate of the embryos. As shown here, the sensitivity of M. cornuarietis embryos test is equal or even higher than other test species like zebrafish embryos and, therefore, this test can be regarded as an alternative or supplement for ecotoxicological studies.

  7. 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...

  8. 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...

  9. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., growth) are the criteria of toxicity. (3) EC 50 means that experimentally derived concentration of test substance in dilution water that is calculated to affect 50 percent of a test population during continuous... same dilution water, conditions, procedures and daphnids from the same population (culture...

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

    SciTech Connect

    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.; Jong, Wim H. de

    2009-10-01

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

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

    SciTech Connect

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

    1987-08-01

    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 out at 20/sup 0/C while all discussions concerning C. dubia appear to relate to temperatures oscillating around 25/sup 0/C. Thus, the response of these two organisms to ethanol was examined at 20/sup 0/C and at 24/sup 0/C.r

  12. Baker's yeast assay procedure for testing heavy metal toxicity

    SciTech Connect

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

    1984-01-01

    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.

  13. When can embryos learn? A test of the timing of learning in embryonic amphibians.

    PubMed

    Sehr, Evie K; Beasley, Lindsay N; Wilson, Kurtis W; Gall, Brian G

    2016-04-01

    Learning is crucial to the survival of organisms across their life span, including during embryonic development. We set out to determine when learning becomes possible in amphibian development by exposing spotted salamander (Ambystoma maculatum) embryos to chemical stimuli from a predator (Ambystoma opacum), nonpredator (Lithobates clamitans), or control at developmental stages 16-21 or 36-38 (Harrison 1969). Once exposures were completed and embryos hatched, we recorded the number of movements and time spent moving of individuals in both groups and all treatments. There was no significant difference in number of movements or time spent moving among any of the treatments. The groups that were exposed to predator stimuli and a blank control at stages 36-38 were also tested to determine whether there was a difference in refuge preference or difference in survivorship when exposed to a predator (marbled salamander). There was no difference in survival or refuge preference between individuals; however, all individuals preferred vegetated over open areas regardless of treatment type. We discuss hypotheses for the absence of embryonic learning in this species and suggest it may be the result of the intensity of the predator-prey interaction between the predator, large marbled salamander larvae, and the prey, spotted salamander larvae. PMID:27110353

  14. Resolving some practical questions about Daphnia acute toxicity tests

    SciTech Connect

    Barera, Y.; Adams, W.J.

    1981-10-01

    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.

  15. Control group response variability in short-term toxicity tests

    SciTech Connect

    Gast, L.C.; Shimp, C.; Wang, Q.; Shukla, R.; Fulk, F.

    1995-12-31

    The US EPA`s National Reference Toxicant Database (NRTDB) has afforded an excellent opportunity to examine and document variability in responses within control groups (i.e. zero concentration of the toxicant.) The NRTDB has compiled acute and chronic reference toxicant test results for eight species and currently contains results for 32 laboratories and generally eight to ten tests for a species within each laboratory. The Ceriodaphnia dubia Survival and Reproduction test and the Pimephales promelas (fathead minnow) Survival and Growth test are the most frequently represented chronic tests with 331 and 144 sets of test data, respectively. For this presentation, Ceriodaphnia dubia reproduction data, expressed as total numbers of young in the test period, and fathead minnow survival and growth data were analyzed using a variance components model. The information regarding the control population is useful in examining the sources of inter and intralaboratory variability of chronic testing. In addition, this control population response variability information will be valuable for characterizing what can be termed as ``practically equivalent responses`` between a control and an effluent. The preliminary analysis indicates considerable between-test variability; however, this variability is not consistent across laboratories. Results of further exploration on this issue will be presented.

  16. 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...

  17. Comparisons of Sediment Test Volumes for Freshwater Solid Phase Sediment Toxicity Tests

    EPA Science Inventory

    Laboratory tests with benthic macroinvertebrates are commonly used to assess the potential toxicity of contaminated sediments, and detailed standard test procedures have been developed for various species. For freshwater, two benthic organisms, Hyalella azteca and Chironomus dil...

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

    SciTech Connect

    Ganeshkumar, Moorthy; Sastry, Thotapalli Parvathaleswara; Sathish Kumar, Muniram; Dinesh, Murugan Girija; Kannappan, Sudalyandi; Suguna, Lonchin

    2012-09-15

    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.

  19. Static renewal tests using Pimephales promelas (fathead minnows). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    SciTech Connect

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21--28, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  20. Troubleshooting methods for toxicity testing of airborne chemicals in vitro.

    PubMed

    Bakand, Shahnaz; Hayes, Amanda

    2010-01-01

    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 to fulfil the essential requirements of toxicity testing for airborne chemicals. Technology has now become available that allows cells to be cultured on permeable microporous membranes in transwell or snapwell inserts providing a very close contact between target cells and test atmospheres to study the cellular interactions caused by airborne chemical exposures without any interfering culture medium. Using a direct exposure technique at the air-liquid interface, target cells can be continuously exposed to airborne chemicals on their apical side, while being nourished from their basolateral side. Test atmospheres with different physicochemical characteristics such as gases, vapours, solid and liquid aerosols and more recently nanoaerosols, can be delivered into human target cells using static and/or direct dynamic exposure methods. Therefore, toxicological risk assessments of airborne chemicals and even complex atmospheres can be achieved using in vitro test methods in parallel with real-time air monitoring techniques to fulfil the general regulatory requirements of newly developed chemical or pharmaceutical products with the potential for inhalational exposure. In this review current toxicological methods for toxicity testing of inhaled chemicals are presented. Further, to demonstrate the potential application of in vitro methods for studying inhalation toxicity, more advanced exposure techniques developed for toxicity screening of airborne chemicals are discussed.

  1. Scanning respirometer for toxicity tests using micro-organisms

    NASA Astrophysics Data System (ADS)

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

    1995-09-01

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

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

    SciTech Connect

    Smith, R.; Johnson, S.C.

    1995-12-31

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

  3. Toxicity testing in the 21st century beyond environmental chemicals.

    PubMed

    Rovida, Costanza; Asakura, Shoji; Daneshian, Mardas; Hofman-Huether, Hana; Leist, Marcel; Meunier, Leo; Reif, David; Rossi, Anna; Schmutz, Markus; Valentin, Jean-Pierre; Zurlo, Joanne; Hartung, Thomas

    2015-01-01

    After the publication of the report titled Toxicity Testing in the 21st Century - A Vision and a Strategy, many initiatives started to foster a major paradigm shift for toxicity testing - from apical endpoints in animal-based tests to mechanistic endpoints through delineation of pathways of toxicity (PoT) in human cell based systems. The US EPA has funded an important project to develop new high throughput technologies based on human cell based in vitro technologies. These methods are currently being incorporated into the chemical risk assessment process. In the pharmaceutical industry, the efficacy and toxicity of new drugs are evaluated during preclinical investigations that include drug metabolism, pharmacokinetics, pharmacodynamics and safety toxicology studies. The results of these studies are analyzed and extrapolated to predict efficacy and potential adverse effects in humans. However, due to the high failure rate of drugs during the clinical phases, a new approach for a more predictive assessment of drugs both in terms of efficacy and adverse effects is getting urgent. The food industry faces the challenge of assessing novel foods and food ingredients for the general population, while using animal safety testing for extrapolation purposes is often of limited relevance. The question is whether the latest paradigm shift proposed by the Tox21c report for chemicals may provide a useful tool to improve the risk assessment approach also for drugs and food ingredients.

  4. EP-toxicity testing of mercury removal resin grout

    SciTech Connect

    Mersman, K.E.

    1984-07-18

    To determine which category a waste will fit into, the EPA requires a classification test. The test, EP-toxicity, consists of a physical integrity test followed by an extraction. For the case of the mercury removal resin grout, the mercury concentration in the extract cannot exceed 0.2 mg/L if the waste is to be classified as ``solid waste.`` Otherwise, the waste is classified as ``hazardous.`` Simulated process solutions were used to load the mercury removal resin. The resin was solidified with the addition of cement and water using a formulation based on grout formulations typically used to solidify power reactor ion exchange resins. Envirodyne Engineers of St. Louis, Missouri, an EPA sanctioned laboratory, performed the EP-toxicity test for the two samples. One sample was a blank which was made with unloaded resin. For the formulation tested, the EP-toxicity test results showed that the mercury removal resin grout does not fit into the ``hazardous waste`` category.

  5. An evaluation of the whole effluent toxicity test method

    SciTech Connect

    Osteen, D.V.

    1999-12-17

    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

  6. Apparent toxicity resulting from the sequestering of nutrient trace metals during standard Selenastrum capricornutum toxicity tests.

    PubMed

    Ward, Timothy J; Rausina, Gary A; Stonebraker, Peter M; Robinson, William E

    2002-10-01

    The water accommodated fractions (WAFs) of aqueous mixtures of three lubricant additives showed significant apparent toxicity to the freshwater alga, Selenastrum capricornutum, and experiments were conducted to investigate the hypothesis that toxicity resulted from the removal of one or more essential nutrients from the test medium by the lubricant additives. Algal growth effects were noted at ashless dispersant A concentrations as low as 0.5 x mg l(-1) and growth was completely inhibited at 100 mg x l(-1). Algal cells transferred from the 100 mg x l(-1) WAF of ashless dispersant A to fresh medium at the end of a standard 96-h toxicity test resumed growing at a rate similar to growth in undosed algal medium, indicating that the effect was algistatic rather than algicidal. Fortifying the iron (Fe) and disodium ethylenediaminetetraacetic acid (EDTA) concentrations of the WAF with 200% of the concentrations used in the formulation of algal medium after 24 h of exposure caused a resumption of algal growth at a rate comparable to the control growth, and a resulting EL50 value above 100 mg x l(-1). Similar effects were observed when the two other lubricant additives were tested at WAF concentrations that completely inhibited algal growth during standard toxicity tests: fortification of a 50 mg x l(-1) WAF of ZnDTP with 1000% of the Fe and EDTA used in the formulation of algal medium caused a resumption of growth at a rate statistically identical to the control growth, and the fortification of a 2800 mg x l(-1) WAF of ashless dispersant B with 700% of the entire complement of nutrients used in the formulation of algal medium caused a resumption of growth at a rate comparable to the control. The indirect toxic effect of these lubricant additives to algae results from the sequestration of one or more nutrient metals essential for algal growth. Standard algal toxicity tests with these lubricant additives may, therefore, have little environmental relevance because the complex

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

    SciTech Connect

    Buchwalter, D.B. |; Linder, G.; Curtis, L.R.

    1996-04-01

    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.

  8. Toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in developing red seabream (Pagrus major) embryo: an association of morphological deformities with AHR1, AHR2 and CYP1A expressions.

    PubMed

    Yamauchi, Masanobu; Kim, Eun-Young; Iwata, Hisato; Shima, Yasuhiro; Tanabe, Shinsuke

    2006-11-16

    The toxicity of dioxins such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is mainly mediated by the aryl hydrocarbon receptor (AHR), which regulates the multiple target genes including cytochrome P4501A (CYP1A). In general, bony fishes, which possess at least two distinct AHRs are one of the most sensitive vertebrates to TCDD in early life stage. However, the physiological and toxicological roles of piscine multiple AHRs are not fully understood, especially in marine fish. To understand which AHR is responsible for TCDD toxicity in a marine fish species, we characterized the early life stage toxicity related to the expression of AHRs and CYP1A in red seabream (Pagrus major). The embryos at 10h post-fertilization (hpf) were treated with 0-100 microg/L TCDD for 80 min waterborne exposure. TCDD dose-dependently elicited developmental toxicities including mortality, yolk sac edema, retarded body growth, spinal deformity, reduced heart rate, shortened snout, underdeveloped fin, heart, and lower jaw. Intriguingly, hemorrhage and pericardium edema, typical TCDD developmental defects noticed in other fish species, were not found in red seabream until test termination. The EC(egg)50s for yolk sac edema, underdeveloped fin, and spinal deformity were 170, 240, and 340 pg/g, respectively. The LC(egg)50 was 360 pg/g embryo, indicating that this species is one of the most sensitive fishes to TCDD toxicity. The expression levels of rsAHR1, rsAHR2 and CYP1A mRNAs were also determined in different developmental stages. The rsAHR2 mRNA expression dose-dependently increased following TCDD exposure, while rsAHR1 mRNA level was not altered. Level of rsAHR2 mRNA measured by two-step real-time PCR was 30 times higher than rsAHR1 in embryos treated with the highest dose. Temporal patterns of rsAHR2 and CYP1A mRNAs were similar in TCDD-treated embryos, representing a significant positive correlation between rsAHR2 and CYP1A mRNA levels, but not between rsAHR1 and CYP1A. In comparison of

  9. Prospects for the development of validated screening tests that measure developmental toxicity potential: view of one skeptic.

    PubMed

    Mirkes, P E

    1996-06-01

    Humans are exposed to a variety of potential developmental toxicants. This fact, combined with the knowledge that human development can be disrupted by "environmental" agents, has led to the development of methods designed to identify potential developmental toxicants. Currently, the principal method used to screen drugs and chemicals that are potential human developmental toxicants is the segment II study (i.e., a study in which prospective drugs and chemicals are tested in pregnant animals). Because of the cost and time involved in such studies and the pressure to reduce the number of animals used in such testing, alternative methods for developmental toxicity testing have been sought. This has resulted in a number of in vitro tests whose aim is to screen large numbers of agents quickly and inexpensively. Although numerous in vitro tests of developmental toxicity have been developed during the last 15 years, no one system or combination of tests have been validated for the purpose intended. Nonetheless, two systems--the limb bud/CNS micromass, and the chick embryo neural retina cell culture (CERC)--continue to be advanced as viable in vitro developmental toxicology tests. The purpose of this commentary is to evaluate the prospects for the development of an in vitro test system(s) that can screen the universe of drugs and chemicals and reliably identify those that require further study and those that do not. The conclusion of this investigator is that the prospects for validating such in vitro tests are not promising. This conclusion is based primarily on the lack of basic knowledge regarding the relevance of end points assayed in the micromass and CERC test systems to those end points known or thought to be critical for normal development.

  10. Prospects for the development of validated screening tests that measure developmental toxicity potential: view of one skeptic.

    PubMed

    Mirkes, P E

    1996-06-01

    Humans are exposed to a variety of potential developmental toxicants. This fact, combined with the knowledge that human development can be disrupted by "environmental" agents, has led to the development of methods designed to identify potential developmental toxicants. Currently, the principal method used to screen drugs and chemicals that are potential human developmental toxicants is the segment II study (i.e., a study in which prospective drugs and chemicals are tested in pregnant animals). Because of the cost and time involved in such studies and the pressure to reduce the number of animals used in such testing, alternative methods for developmental toxicity testing have been sought. This has resulted in a number of in vitro tests whose aim is to screen large numbers of agents quickly and inexpensively. Although numerous in vitro tests of developmental toxicity have been developed during the last 15 years, no one system or combination of tests have been validated for the purpose intended. Nonetheless, two systems--the limb bud/CNS micromass, and the chick embryo neural retina cell culture (CERC)--continue to be advanced as viable in vitro developmental toxicology tests. The purpose of this commentary is to evaluate the prospects for the development of an in vitro test system(s) that can screen the universe of drugs and chemicals and reliably identify those that require further study and those that do not. The conclusion of this investigator is that the prospects for validating such in vitro tests are not promising. This conclusion is based primarily on the lack of basic knowledge regarding the relevance of end points assayed in the micromass and CERC test systems to those end points known or thought to be critical for normal development. PMID:8910978

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

    SciTech Connect

    Brandt, O.M.; Fujimura, R.W.; Finlayson, B.J. )

    1993-03-01

    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.

  12. Developmental toxicity, EROD, and CYP1A mRNA expression in zebrafish embryos exposed to dioxin-like PCB126.

    PubMed

    Liu, Han; Nie, Fang-Hong; Lin, Hong-Ying; Ma, Yi; Ju, Xiang-Hong; Chen, Jin-Jun; Gooneratne, Ravi

    2016-02-01

    Dioxin-like PCB126 is a persistent organic pollutant that causes a range of syndromes including developmental toxicity. Dioxins have a high affinity for aryl hydrocarbon receptor (AhR) and induce cytochrome P4501A (CYP1A). However, the role of CYP1A activity in developmental toxicity is less clear. To better understand dioxin induced developmental toxicity, we exposed zebrafish (Danio rerio) embryos to PCB126 at concentrations of 0, 16, 32, 64, and 128 μg L(-1) from 3-h post-fertilization (hpf) to 168 hpf. The embryonic survival rate decreased at 144 and 168 hpf. The fry at 96 hpf displayed gross developmental malformations, including pericardial and yolk sac edema, spinal curvature, abnormal lower jaw growth, and non-inflated swim bladder. The pericardial and yolk sac edema rate significantly increased and the heart rate declined from 96 hpf compared with the controls. PCB126 did not alter the hatching rate. To elucidate the mechanism of PCB126-induced developmental toxicity, we conducted ethoxyresorufin-O-deethylase (EROD) in vivo assay to determine CYP1A enzyme activity, and real-time PCR to study the induction of CYP1A mRNA gene expression in embryo/larval zebrafish at 24, 72, 96, and 132 hpf. In vivo EROD activity was induced by PCB126 at 16 μg L(-1) concentration as early as 72 hpf but significant increases were observed only in zebrafish exposed to 64 and 128 μg L(-1) doses (p < 0.005) at 72, 96, and 132 hpf. Induction of CYP1A mRNA expression was significantly upregulated in zebrafish exposed to 32 and 64 μg L(-1) at 24, 72, 96, and 132 hpf. Overall, the severe pericardial and yolk sac edema and reduced heart rate suggest that heart defects are a sensitive endpoint, and the general trend of dose-dependent increase in EROD activity and induction of CYP1A mRNA gene expression provide evidence that the developmental toxicity of PCB126 to zebrafish embryos is mediated by activation of AhR.

  13. The Role of Toxicity Testing in NASA's Future Missions

    NASA Technical Reports Server (NTRS)

    Whitfield, Steve; Davis, Samuel; Wise, Harry; Moore, Robin

    2005-01-01

    NASA has deemed it necessary to perform the Toxicity Test (offgassing of toxic products) on all non-metallic materials proposed for use in habitable environments onboard the Shuttle and International Space Station flS,!J. This requirement stems from the desire to maintain a healthy, breathable atmosphere for the astronauts. As Shuttle missions have lengthened and with the habitation of the International Space Station, the need for understanding and controlling the contaminants in breathable atmospheres has increased. The increased duration of humans in space present two concerns to the astronauts with regard to their breathing air: 1. Breathing the on-board air. 2. Improved cleaning/filtering of existing air. Trends using existing toxicity data for materials and an understanding of the air cleaning/filtering capabilities in relation to Spacecraft Maximum Allowable Concentrations (SMAC) of offgassed components are explored. Recommendations are made for materials selection practices that should be followed to ensure a safe and healthy breathing environment for astronauts aboard these long term projects. The importance and relevance of Toxicity testing and materials selection in conjunction with the new NASA missions of creating a human presence on the Moon and traveling to Mars are described.

  14. Genotoxic and teratogenic effect of freshwater sediment samples from the Rhine and Elbe River (Germany) in zebrafish embryo using a multi-endpoint testing strategy.

    PubMed

    Garcia-Käufer, M; Gartiser, S; Hafner, C; Schiwy, S; Keiter, S; Gründemann, C; Hollert, H

    2015-11-01

    The embryotoxic potential of three model sediment samples with a distinct and well-characterized pollutant burden from the main German river basins Rhine and Elbe was investigated. The Fish Embryo Contact Test (FECT) in zebrafish (Danio rerio) was applied and submitted to further development to allow for a comprehensive risk assessment of such complex environmental samples. As particulate pollutants are constructive constituents of sediments, they underlay episodic source-sink dynamics, becoming available to benthic organisms. As bioavailability of xenobiotics is a crucial factor for ecotoxicological hazard, we focused on the direct particle-exposure pathway, evaluating throughput-capable endpoints and considering toxicokinetics. Fish embryo and larvae were exposed toward reconstituted (freeze-dried) sediment samples on a microcosm-scale experimental approach. A range of different developmental embryonic stages were considered to gain knowledge of potential correlations with metabolic competence during the early embryogenesis. Morphological, physiological, and molecular endpoints were investigated to elucidate induced adverse effects, placing particular emphasis on genomic instability, assessed by the in vivo comet assay. Flow cytometry was used to investigate the extent of induced cell death, since cytotoxicity can lead to confounding effects. The implementation of relative toxicity indices further provides inter-comparability between samples and related studies. All of the investigated sediments represent a significant ecotoxicological hazard by disrupting embryogenesis in zebrafish. Beside the induction of acute toxicity, morphological and physiological embryotoxic effects could be identified in a concentration-response manner. Increased DNA strand break frequency was detected after sediment contact in characteristic non-monotonic dose-response behavior due to overlapping cytotoxic effects. The embryonic zebrafish toxicity model along with the in vivo comet

  15. Use of DNA strand damage (Comet assay) and embryo hatching effects to assess contaminant exposure in blue crab (Callinectes sapidus) embryos

    SciTech Connect

    Lee, R.F.; Steinert, S.A.; Nakayama, K.; Oshima, Y.

    1999-07-01

    After fertilization, blue crab eggs are embedded in a sponge which is attached to the female abdomen during embryo development. Embryos after 9 stages in the egg sac hatch into a swimming zoea stage (stage 10). The authors have developed a bioassay where embryo development is monitored in culture plates with and without toxicants in the water. Toxicant effects are based on determining the percentage of embryos which hatch to zoea. Hatching EC{sub 50} (toxicant concentration at which 50% of the embryos fail to hatch) for a number of pesticides, organometallics and metals were determined. The test takes from 2 to 6 days depending on the embryo stage selected for the study. In addition to embryo development effects the prevalence of DNA single-strand breaks in individual embryo cells were determined using the single cell gel electrophoresis method (Comet assay). A good correlation between DNA strand breakage and embryo defects was found after exposure to genotoxic contaminants. Thus, the bioassay linking DNA damage to embryo hatching effects is rapid, sensitive and mechanistically relevant.

  16. Decreased Dissolution of ZnO by Iron Doping Yields Nanoparticles with Reduced Toxicity in the Rodent Lung and Zebrafish Embryos

    PubMed Central

    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.

    2014-01-01

    We have recently shown that the dissolution of ZnO nanoparticles and Zn2+ shedding leads to a series of sub-lethal and lethal toxicological responses at 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 Zn2+ 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

  17. In situ toxicity testing with locally collected Daphnia

    SciTech Connect

    Snyder-Conn, E.

    1993-07-01

    Daphnia middlendorffiana from local tundra ponds were transplanted into five reserve pits (sumps with used drilling wastes and precipitation) at drill sites in the Prudhoe Bay oil field. Concurrently, Daphnia were transplanted into tundra ponds adjacent to the reserve pits (near ponds), into more distant but connected ponds (distant ponds), and into control ponds to evaluate the toxicity of the fluids along contaminant gradients. Twenty adult Daphnia were placed in eight waxed flow-through containers and exposed to the conditions of each test site. In each exposure container, the ratios of the number of dead Daphnia to the total number of adult Daphnia, the number of young Daphnia to the total number of adult Daphnia, the number of molting Daphnia to the total number of adult Daphnia, and the number of released ephippia to the total number of adult Daphnia were determined. The results not only indicate the utility of in situ testing of invertebrate toxicity but suggest that under certain conditions in situ tests may be more sensitive than traditional laboratory toxicity tests.

  18. Antioxidant, Antimicrobial Activity and Toxicity Test of Pilea microphylla

    PubMed Central

    Modarresi Chahardehi, Amir; Ibrahim, Darah; Fariza Sulaiman, Shaida

    2010-01-01

    A total of 9 plant extracts were tested, using two different kinds of extracting methods to evaluate the antioxidant and antimicrobial activities from Pilea microphylla (Urticaceae family) and including toxicity test. Antioxidant activity were tested by using DPPH free radical scavenging, also total phenolic contents and total flavonoid contents were determined. Toxicity assay carried out by using brine shrimps. Methanol extract of method I (ME I) showed the highest antioxidant activity at 69.51 ± 1.03. Chloroform extract of method I (CE I) showed the highest total phenolic contents at 72.10 ± 0.71 and chloroform extract of method II (CE II) showed the highest total flavonoid contents at 60.14 ± 0.33. The antimicrobial activity of Pilea microphylla extract was tested in vitro by using disc diffusion method and minimum inhibitory concentration (MIC). The Pilea microphylla extract showed antibacterial activity against some Gram negative and positive bacteria. The extracts did not exhibit antifungal and antiyeast activity. The hexane extract of method I (HE I) was not toxic against brine shrimp (LC50 value was 3880 μg/ml). Therefore, the extracts could be suitable as antimicrobial and antioxidative agents in food industry. PMID:20652052

  19. Toxicity testing and instream biological monitoring in evaluating municipal effluents

    SciTech Connect

    Krier, K.; Pontasch, K.

    1995-12-31

    Twelve streams receiving municipal wastewater treatment plant effluents were evaluated in riffle areas above and below the outfall using the Environmental Protection Agency`s Rapid Bioassessment Protocols (RBPs) for benthic macroinvertebrates. Eight of the sites evaluated using RBP 1 exhibited stream health in the downstream riffles equaling or exceeding the upstream riffles. RBP 1 results suggested possible impacts at the remaining four sites, and these sites were more intensely evaluated using RBPs 2 and 3, acute effluent toxicity tests with Daphnia magna, and quantification of periphytic chlorophyll a and ash free dry weight (AFDW). Results from RBP 2 indicated three of the four sites evaluated have similar taxonomic richness above and below the outfall, while one site is heavily impacted by organic pollutants. Toxicity tests with 100% effluent resulted in no mortality with any of the four effluents tested. Relative to the respective upstream sites, chlorophyll a was significantly increased at one downstream site and significantly reduced at another. AFDW was similar above and below the outfalls in all streams. These results suggest that laboratory toxicity tests may not always be adequate predictors of instream biological effects.

  20. Discovery of Quinoline-Derived Trifluoromethyl Alcohols, Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model.

    PubMed

    Sittaramane, Vinoth; Padgett, Jihan; Salter, Philip; Williams, Ashley; Luke, Shauntelle; McCall, Rebecca; Arambula, Jonathan F; Graves, Vincent B; Blocker, Mark; Van Leuven, David; Bowe, Keturah; Heimberger, Julia; Cade, Hannah C; Immaneni, Supriya; Shaikh, Abid

    2015-11-01

    In this study the rational design, synthesis, and anticancer activity of quinoline-derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp(3) -C-H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4-trifluoro-3-hydroxy-3-(quinolin-2-ylmethyl)butanoate (1), 2-benzyl-1,1,1-trifluoro-3-(quinolin-2-yl)propan-2-ol (2), and trifluoro-3-(isoquinolin-1-yl)-2-(thiophen-2-yl)propan-2-ol (3). Compounds 2 and 3 were found to be more toxic than compound 1; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2, with an LC50 value of 14.14 μm, has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents.

  1. Non-animal Replacements for Acute Toxicity Testing.

    PubMed

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

    2015-07-01

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

  2. Non-animal Replacements for Acute Toxicity Testing.

    PubMed

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

    2015-07-01

    Current approaches to predicting adverse effects in humans from acute toxic exposure to cosmetic ingredients still heavily necessitate the use of animals under EU legislation, particularly in the context of the REACH system, when cosmetic ingredients are also destined for use in other industries. These include the LD50 test, the Up-and-Down Procedure and the Fixed Dose Procedure, which are regarded as having notable scientific deficiencies and low transferability to humans. By expanding on previous in vitro tests, such as the animal cell-based 3T3 Neutral Red Uptake (NRU) assay, this project aims to develop a truly animal-free predictive test for the acute toxicity of cosmetic ingredients in humans, by using human-derived cells and a prediction model that does not rely on animal data. The project, funded by Innovate UK, will incorporate the NRU assay with human dermal fibroblasts in animal product-free culture, to generate an in vitro protocol that can be validated as an accepted replacement for the currently available in vivo tests. To date, the project has successfully completed an assessment of the robustness and reproducibility of the method, by using sodium lauryl sulphate (SLS) as a positive control, and displaying analogous results to those of the original studies with mouse 3T3 cells. Currently, the testing of five known ingredients from key groups (a surfactant, a preservative, a fragrance, a colour and an emulsifier) is under way. The testing consists of initial range-finding runs followed by three valid runs of a main experiment with the appropriate concentration ranges, to generate IC50 values. Expanded blind trials of 20 ingredients will follow. Early results indicate that this human cell-based test holds the potential to replace aspects of in vivo animal acute toxicity testing, particularly with reference to cosmetic ingredients. PMID:26256397

  3. Technical considerations regarding toxicity testing of commercial bioremediation agents

    SciTech Connect

    Bidwell, J.R.; Cavender, R.C.; Cherry, D.S.; Merski, A.T.; Cianciarulo, F.L.

    1995-12-31

    The toxicological evaluation of commercial bioremediation agents (CBAs) for use on oil spills is under consideration by the USEPA. Currently, acute and chronic bioassays are conducted with the CBA alone and with CBA that has been diluted with the water soluble fraction (WSF) of a crude oil. Endpoints are expressed as a concentration of the CBA. This approach may not address the toxicological issue of CBA use since it (1) does not determine if the CBA affects toxicity of the oil itself, and (2) does not consider temporal aspects associated with byproducts of oil degradation. The present study was conducted to address these issues. A CBA was mixed with unweathered crude oil from 1 to 42 days. The WSF of the mixture was then drawn off and acute bioassays were conducted with silverside minnows, Menidia beryllina, and mysid shrimp, Mysidopsis bahia. For silversides, 96-hr LC50 values ranged from 42.7% WSF after 1 day mixing to 10.5% after 42 days. Toxicity increased sharply between days 4 and 7 when the 96-hr LC50 dropped from 39.0 to 18.2% WSF. A similar trend occurred for mysid shrimp. The presence of the CBA caused a more rapid increase in the toxicity of the oil as compared to bioassays in which oil was mixed alone and then tested. These data indicate that the interaction of CBAs with oil, and associated temporal trends in toxicity, are important aspects to consider in hazard evaluation of these products. The current proposed CBA toxicity testing protocol does not effectively address these issues.

  4. Applicability of subchronic toxicity test with Hyalella azteca for toxicity identification evaluation programs

    SciTech Connect

    Putt, A.E.; Jop, K.M.

    1995-12-31

    A series of screening tests including the short-term chronic exposure of Ceriodaphnia dubia to sediment pore waters, 10-day exposures of Chironomus tentans and Hyalella azteca to bulk sediments and a bioaccumulation study with Lumbriculus variegatus were performed as part of an ecological risk assessment of Plow Shop Pond, Fort Devens, Massachusetts. Chronic endpoints such as reproduction and growth indicated sediment toxicity, however, a toxicity identification evaluation program was initiated to further define the source and extent of the toxicity. A short-term chronic exposure with C. dubia was a logical choice for the TIE, however, since amphipods are epibenthic organisms, they are a better surrogate of sediment dwelling organisms than a water column species such as C. dubia. Observations performed during H. azteca culture suggested that this species of amphipod could thrive in the water column for up to three weeks. Therefore, 7-day old H. azteca were exposed to pore water samples under static-renewal conditions for 10 days. Survival and growth (i.e., dry weight) were determined at the termination of each exposure. Laboratory control group performance consistently averaged a {>=}90% survival and {>=}43 {micro}g of dry weight per amphipod. Growth of amphipods used in each exposure generally exceeded two times the initial body weight after 10 days of exposure. Previous studies have indicated that the growth and reproductive response of H. azteca are positively correlated for a given set of exposure conditions. The results of these 10-day subchronic exposures with H. azteca provide a consistent and reliable measure of the chronic sediment toxicity with a benthic invertebrate for toxicity identification evaluation programs.

  5. Undetected Toxicity Risk in Pharmacogenetic Testing for Dihydropyrimidine Dehydrogenase

    PubMed Central

    Falvella, Felicia Stefania; Caporale, Marta; Cheli, Stefania; Martinetti, Antonia; Berenato, Rosa; Maggi, Claudia; Niger, Monica; Ricchini, Francesca; Bossi, Ilaria; Di Bartolomeo, Maria; Sottotetti, Elisa; Bernardi, Francesca Futura; de Braud, Filippo; Clementi, Emilio; Pietrantonio, Filippo

    2015-01-01

    Fluoropyrimidines, the mainstay agents for the treatment of colorectal cancer, alone or as a part of combination therapies, cause severe adverse reactions in about 10%–30% of patients. Dihydropyrimidine dehydrogenase (DPD), a key enzyme in the catabolism of 5-fluorouracil, has been intensively investigated in relation to fluoropyrimidine toxicity, and several DPD gene (DPYD) polymorphisms are associated with decreased enzyme activity and increased risk of fluoropyrimidine-related toxicity. In patients carrying non-functional DPYD variants (c.1905+1G>A, c.1679T>G, c.2846A>T), fluoropyrimidines should be avoided or reduced according to the patients’ homozygous or heterozygous status, respectively. For other common DPYD variants (c.496A>G, c.1129-5923C>G, c.1896T>C), conflicting data are reported and their use in clinical practice still needs to be validated. The high frequency of DPYD polymorphism and the lack of large prospective trials may explain differences in studies’ results. The epigenetic regulation of DPD expression has been recently investigated to explain the variable activity of the enzyme. DPYD promoter methylation and its regulation by microRNAs may affect the toxicity risk of fluoropyrimidines. The studies we reviewed indicate that pharmacogenetic testing is promising to direct personalised dosing of fluoropyrimidines, although further investigations are needed to establish the role of DPD in severe toxicity in patients treated for colorectal cancer. PMID:25906475

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

    ERIC Educational Resources Information Center

    Porntrai, Supaporn; Damrongphol, Praneet

    2008-01-01

    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…

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

    SciTech Connect

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

    2000-01-01

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

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

    SciTech Connect

    Douglas, W.S.; Veil, J.A.

    1996-10-01

    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.

  9. Field assessments in conjunction with whole effluent toxicity testing

    SciTech Connect

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

    2000-01-01

    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.

  10. 78 FR 69414 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... October 21, 2011 (76 FR 65385) (FRL-8885-5) (docket ID number EPA-HQ-OPPT-2009-0112). The table in this... AGENCY Toxic Substances Control Act Chemical Testing; Receipt of Test Data AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces EPA's receipt of test data on...

  11. Fish embryo tests with Danio rerio as a tool to evaluate surface water and sediment quality in rivers influenced by wastewater treatment plants using different treatment technologies.

    PubMed

    Thellmann, Paul; Köhler, Heinz-R; Rößler, Annette; Scheurer, Marco; Schwarz, Simon; Vogel, Hans-Joachim; Triebskorn, Rita

    2015-11-01

    In order to evaluate surface water and the sediment quality of rivers connected to wastewater treatment plants (WWTPs) with different treatment technologies, fish embryo tests (FET) with Danio rerio were conducted using native water and sediment samples collected upstream and downstream of four WWTPs in Southern Germany. Two of these WWTPs are connected to the Schussen River, a tributary of Lake Constance, and use a sand filter with final water purification by flocculation. The two others are located on the rivers Schmiecha and Eyach in the area of the Swabian Alb and were equipped with a powdered activated carbon stage 20 years ago, which was originally aimed at reducing the release of stains from the textile industry. Several endpoints of embryo toxicity including mortality, malformations, reduced hatching rate, and heart rate were investigated at defined time points of embryonic development. Higher embryotoxic potentials were found in water and sediments collected downstream of the WWTPs equipped with sand filtration than in the sample obtained downstream of both WWTPs upgraded with a powdered activated carbon stage. PMID:25391229

  12. Fish embryo tests with Danio rerio as a tool to evaluate surface water and sediment quality in rivers influenced by wastewater treatment plants using different treatment technologies.

    PubMed

    Thellmann, Paul; Köhler, Heinz-R; Rößler, Annette; Scheurer, Marco; Schwarz, Simon; Vogel, Hans-Joachim; Triebskorn, Rita

    2015-11-01

    In order to evaluate surface water and the sediment quality of rivers connected to wastewater treatment plants (WWTPs) with different treatment technologies, fish embryo tests (FET) with Danio rerio were conducted using native water and sediment samples collected upstream and downstream of four WWTPs in Southern Germany. Two of these WWTPs are connected to the Schussen River, a tributary of Lake Constance, and use a sand filter with final water purification by flocculation. The two others are located on the rivers Schmiecha and Eyach in the area of the Swabian Alb and were equipped with a powdered activated carbon stage 20 years ago, which was originally aimed at reducing the release of stains from the textile industry. Several endpoints of embryo toxicity including mortality, malformations, reduced hatching rate, and heart rate were investigated at defined time points of embryonic development. Higher embryotoxic potentials were found in water and sediments collected downstream of the WWTPs equipped with sand filtration than in the sample obtained downstream of both WWTPs upgraded with a powdered activated carbon stage.

  13. Bioavailability of fluoranthene in freshwater sediment toxicity tests

    SciTech Connect

    Suedel, B.C.; Rodgers, J.H. Jr. ); Clifford, P.A. )

    1993-01-01

    To examine equilibrium-partitioning model predictions of interstitial water concentrations of fluoranthene as part of the equilibrium-partitioning (EqP) approach to sediment quality criteria development, the bioavailability (toxicity) of fluoranthene-amended sediment to Hyalella azteca, Daphnia magna, and Chironomus tentans was determined. Fluoranthene was added to three freshwater sediments with similar organic carbon content. Predicted interstitial water concentrations from the equilibrium-partitioning model were similar to measured interstitial water concentrations for WRFS and TR sediment, but the model underpredicted measured values for LF sediment by a factor of two. EC50s for Daphnia magna, Hyalella azteca, and Chironomus tentans in interstitial water were a factor of two to five greater for LF than for WRFS and TR sediments. Factors other than organic carbon content of sediments probably contributed to the variability in bioavailability of fluoranthene. Based on 10-d sediment toxicity tests with Hylella azteca, Daphnia magna, and Chironomus tentans, organic carbon-normalized sediment concentrations were better predictors of toxicity than interstitial water and bulk sediment fluoranthene concentrations. In 10-d aqueous-phase tests with fluoranthene, Chironomus tentans and Hyalella azteca were twice as sensitive as Daphnia magna.

  14. [Toxic and teratogenic effects of the ammonium salt of fosamine on the development of quail and chick embryos].

    PubMed

    Lutz-Ostertag, Y

    1983-01-01

    The effects of a commercial spray preparation of ammonium salt ppf fosamine (a defoliant) on quail and chick eggs have been studied. The results lead us to conclude that under the stated conditions the product has little embryotoxicity. However, it does have teratogenic effects on the steal and on the cervical, dorsal and posterior axial skeleton. The observed malformations are more severe and appear more frequently in quail than in chick embryos. PMID:6685456

  15. [Toxic and teratogenic effects of the ammonium salt of fosamine on the development of quail and chick embryos].

    PubMed

    Lutz-Ostertag, Y

    1983-01-01

    The effects of a commercial spray preparation of ammonium salt ppf fosamine (a defoliant) on quail and chick eggs have been studied. The results lead us to conclude that under the stated conditions the product has little embryotoxicity. However, it does have teratogenic effects on the steal and on the cervical, dorsal and posterior axial skeleton. The observed malformations are more severe and appear more frequently in quail than in chick embryos.

  16. Establishing relative sensitivities of various toxicity testing organisms to ammonia

    SciTech Connect

    Karle, L.M.; Mayhew, H.L.; Barrows, M.E.; Karls, R.K.

    1994-12-31

    The toxicity of ammonia to various organisms was examined to develop a baseline for mortality in several commonly used testing species. This baseline data will assist in choosing the proper test species and in interpreting results as they pertain to ammonia. Responses for two juvenile fish species, three marine amphipods, and two species of mysid shrimp were compared for their sensitivity to levels of ammonia. All mortality caused by ammonia in the bottom-dwelling Citharichthys stigmaeus occurred within 24 h of exposure, whereas mortality in the silverside, Menidia beryllina, occurred over the entire 96-h test duration. Responses to ammonia varied among the amphipods Rhepoxynius abronius, Ampelisca abdita, and Eohaustorius estuarius. R. abronius and A. abdita showed similar sensitivity to ammonia at lower concentrations; A. abdita appeared more sensitive than R. abronius at levels above 40 mg/L. Concentrations of ammonia required to produce significant mortality in the amphipod E. estuarius were far higher than the other species examined (> 100 mg/L NH{sub 3}). A comparison of ammonia toxicity with two commonly used invertebrates, Holmesimysis sculpts and Mysidopsis bahia, suggest that these two species of mysid have similar sensitivities to ammonia. Further studies with ammonia that examine sensitivity of different organisms should be conducted to assist regulatory and environmental agencies in determining appropriate test species and in interpreting toxicological results as they may be affected by levels of ammonia.

  17. Current and future needs for developmental toxicity testing.

    PubMed

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

    2011-10-01

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

  18. Testing toxic substances for protection of the environment.

    PubMed

    Draggan, S; Giddings, J M

    1978-01-01

    The Toxic Substances Control Act requires pre-production testing of chemicals for potential hazards to human and environmental health. Effective control of chemicals requires evaluations of chemical hazard that go beyond determinations of toxicity to humans to include the effects, transport, and fat of chemicals in the environemnt. Formulation of meaningful hazard evaluations depends on integrating information from tests of chemical effects, transport, and fate or by developing testing tools that integrate these factors during experimentation. Chemical effects may be acute or chronic and they may be observed individual organisms, populations or organisms, or in total ecosystems. Chemical transport through the environment depends on physico-chemical characteristics of the chemical and the medium (soil, water, or air) as well as environmental factors and biotic processes. The ultimate fate of chemicals (persistence, transformation, or degradation) is determined by numerous physical and biological processes occurring in the environment, and must be acknowledged to effectively determine the hazard. Many techniques are available for the separate and routine evaluation of the effects, transport and fate of environmental contaminants. However, separate identification of the importance and magnitude of each of these factors limits their utility in assessments of chemical hazard. The microcosm (model ecosystem) method integrates many of these tests in replicable experimental units, and may provide substantial information on chemical hazard in ecosystem context. PMID:622550

  19. Combinatorial QSAR modeling of chemical toxicants tested against Tetrahymena pyriformis.

    PubMed

    Zhu, Hao; Tropsha, Alexander; Fourches, Denis; Varnek, Alexandre; Papa, Ester; Gramatica, Paola; Oberg, Tomas; Dao, Phuong; Cherkasov, Artem; Tetko, Igor V

    2008-04-01

    Selecting most rigorous quantitative structure-activity relationship (QSAR) approaches is of great importance in the development of robust and predictive models of chemical toxicity. To address this issue in a systematic way, we have formed an international virtual collaboratory consisting of six independent groups with shared interests in computational chemical toxicology. We have compiled an aqueous toxicity data set containing 983 unique compounds tested in the same laboratory over a decade against Tetrahymena pyriformis. A modeling set including 644 compounds was selected randomly from the original set and distributed to all groups that used their own QSAR tools for model development. The remaining 339 compounds in the original set (external set I) as well as 110 additional compounds (external set II) published recently by the same laboratory (after this computational study was already in progress) were used as two independent validation sets to assess the external predictive power of individual models. In total, our virtual collaboratory has developed 15 different types of QSAR models of aquatic toxicity for the training set. The internal prediction accuracy for the modeling set ranged from 0.76 to 0.93 as measured by the leave-one-out cross-validation correlation coefficient ( Q abs2). The prediction accuracy for the external validation sets I and II ranged from 0.71 to 0.85 (linear regression coefficient R absI2) and from 0.38 to 0.83 (linear regression coefficient R absII2), respectively. The use of an applicability domain threshold implemented in most models generally improved the external prediction accuracy but at the same time led to a decrease in chemical space coverage. Finally, several consensus models were developed by averaging the predicted aquatic toxicity for every compound using all 15 models, with or without taking into account their respective applicability domains. We find that consensus models afford higher prediction accuracy for the

  20. What food and feeding rates are optimum for the Chironomus dilutus sediment toxicity test method?

    EPA Science Inventory

    Laboratory tests with benthic macroinvertebrates conducted using standard toxicity test procedures are used to assess the potential toxicity of contaminated sediments. Results are compared across sites or for batches of samples, and the performance of organisms in control treatme...

  1. Beryllium toxicity testing in the suspension culture of mouse fibroblasts.

    PubMed

    Rössner, P; Bencko, V

    1980-01-01

    Suspension culture of mouse fibroblast cell line L-A 115 was used to test beryllium toxicity in the presence of magnesium ions. Beryllium added to the MEM cultivation medium was bound in a complex with sulphosalicylic acid BeSSA complex, because the use of beryllium chloride turned out to yield ineffective beryllium phosphate that formed macroscopically detectable insoluble opacities. The BeSSA complex was used in the concentration range: 10(-3)--10(-9)M, magnesium was used in 3 concentrations: 10(-1)M, 5 x 10(-2)M and 10(-2)M. Growth curve analysis revealed pronounced beryllium toxicity at the concentration of 10(-3)M, magnesium-produced toxic changes were observed only at the concentration of 10(-1)M. No competition between the beryllium and magnesium ions was recorded. It is assumed that the possible beryllium-magnesium competition was significantly modified by the use of BeSSA complex-bound beryllium.

  2. Assessment of the individual and mixture toxicity of cadmium, copper and oxytetracycline, on the embryo-larval development of the sea urchin Paracentrotus lividus.

    PubMed

    Gharred, Tahar; Jebali, Jamel; Belgacem, Mariem; Mannai, Rabeb; Achour, Sami

    2016-09-01

    Multiple pollutions by trace metals and pharmaceuticals have become one of the most important problems in marine coastal areas because of its excessive toxicity on organisms living in this area. This study aimed to assess the individual and mixture toxicity of Cu, Cd, and oxytetracycline frequently existing in the contaminated marine areas and the embryo-larval development of the sea urchin Paracentrotus lividus. The individual contamination of the spermatozoid for 1 h with the increasing concentrations of Cd, Cu, and OTC decreases the fertility rate and increases larvae anomalies in the order Cu > Cd > OTC. Moreover, the normal larva frequency and the length of spicules were more sensitive than the fertilization rate and normal gastrula frequency endpoints. The mixture toxicity assessed by multiple experimental designs showed clearly that concentrations of Cd, Cu, and OTC superior to 338 μg/L, 0.56 μg/L, and 0.83 mg/L, respectively, cause significant larva malformations. PMID:27259955

  3. Tests for oil/dispersant toxicity: In situ laboratory assays

    SciTech Connect

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

    1995-12-31

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

  4. Organotypic liver culture models: Meeting current challenges in toxicity testing

    PubMed Central

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

    2012-01-01

    Prediction of chemical-induced hepatotoxicity in humans from in vitro data continues to be a significant challenge for the pharmaceutical and chemical industries. Generally, conventional in vitro hepatic model systems (i.e. 2-D static monocultures of primary or immortalized hepatocytes) are limited by their inability to maintain histotypic and phenotypic characteristics over time in culture, including stable expression of clearance and bioactivation pathways, as well as complex adaptive responses to chemical exposure. These systems are less than ideal for longer-term toxicity evaluations and elucidation of key cellular and molecular events involved in primary and secondary adaptation to chemical exposure, or for identification of important mediators of inflammation, proliferation and apoptosis. Progress in implementing a more effective strategy for in vitro-in vivo extrapolation and human risk assessment depends on significant advances in tissue culture technology and increasing their level of biological complexity. This article describes the current and ongoing need for more relevant, organotypic in vitro surrogate systems of human liver and recent efforts to recreate the multicellular architecture and hemodynamic properties of the liver using novel culture platforms. As these systems become more widely used for chemical and drug toxicity testing, there will be a corresponding need to establish standardized testing conditions, endpoint analyses and acceptance criteria. In the future, a balanced approach between sample throughput and biological relevance should provide better in vitro tools that are complementary with animal testing and assist in conducting more predictive human risk assessment. PMID:22582993

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

    PubMed

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

    2015-06-01

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

  6. A SURROGATE SUBCHRONIC TOXICITY TEST METHOD FOR WATERS WITH HIGH TOTAL DISSOLVED SOLIDS

    EPA Science Inventory

    Total dissolved solids (TDS) are often identified as a toxicant in whole-effluent toxicity (WET) testing. The primary test organism used in WET testing, Ceriodaphnia dubia, is very sensitive to TDS ions, which can be problematic when differentiating the toxicity of TDS from those...

  7. 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...

  8. Toxicity assessment and vitellogenin expression in zebrafish (Danio rerio) embryos and larvae acutely exposed to bisphenol A, endosulfan, heptachlor, methoxychlor and tetrabromobisphenol A.

    PubMed

    Chow, Wing Shan; Chan, Winson Ka-Lun; Chan, King Ming

    2013-07-01

    Organochlorine pesticides and brominated flame retardants, such as tetrabromobisphenol A and polybrominated diphenyl ethers, pose an environmental hazard owing to their persistence, low solubility and estrogenic effects, and concerns have been raised regarding their effects on aquatic biota. In the present study, zebrafish embryos and larvae were used as a model to investigate the sublethal and lethal effects of three different organochlorine pesticides, namely methoxychlor, endosulfan and heptachlor, as well as the flame retardant tetrabromobisphenol A, and its precursor compound bisphenol A. Preliminary data for chemical exposure tests were obtained by determining the 96 h median effective concentration EC50 (hatching rate) and 96 h median lethal concentration LC50 . Quantitative polymerase chain reaction was used to investigate the gene expression levels of the biomarker vitellogenin (vtg1) after 96 h exposures to 10, 25, 50 and 75% of the 96 h EC50 value for embryos and 96 h LC50 value for larvae. The use of vtg1 mRNA induction in zebrafish embryos and larvae was found to be a sensitive biomarker of exposure to these organic compounds, and was helpful in elucidating their adverse effects and setting water quality guidelines.

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

    PubMed

    Knight, Andrew

    2008-01-01

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

  10. Toxicity testing, risk assessment, and options for dredged material management.

    PubMed

    Munns, Wayne R; Berry, Walter J; Dewitt, Theodore H

    2002-04-01

    Programs for evaluating proposed discharges of dredged material into waters of the United States specify a tiered testing and evaluation protocol that includes performance of acute and chronic bioassays to assess toxicity of the dredged sediments. Although these evaluations reflect the toxicological risks associated with disposal activities to some degree, analysis activities are limited to the sediments of each dredging project separately. Cumulative risks to water column and benthic organisms at and near the designated disposal site are therefore difficult to assess. An alternate approach is to focus attention on the disposal site, with the goal of understanding more directly the risks of multiple disposal events to receiving ecosystems. Here we review current US toxicity testing and evaluation protocols, and describe an application of ecological risk assessment that allows consideration of the temporal and spatial components of risk to receiving aquatic ecosystems. When expanded to include other disposal options, this approach can provide the basis for holistic management of dredged material disposal. PMID:12139319

  11. Toxicity assessment of water-accommodated fractions from two different oils using a zebrafish (Danio rerio) embryo-larval bioassay with a multilevel approach.

    PubMed

    Perrichon, Prescilla; Le Menach, Karyn; Akcha, Farida; Cachot, Jérôme; Budzinski, Hélène; Bustamante, Paco

    2016-10-15

    Petroleum compounds from chronic discharges and oil spills represent an important source of environmental pollution. To better understand the deleterious effects of these compounds, the toxicity of water-accommodated fractions (WAF) from two different oils (brut Arabian Light and Erika heavy fuel oils) were used in this study. Zebrafish embryos (Danio rerio) were exposed during 96h at three WAF concentrations (1, 10 and 100% for Arabian Light and 10, 50 and 100% for Erika) in order to cover a wide range of polycyclic aromatic hydrocarbon (PAH) concentrations, representative of the levels found after environmental oil spills. Several endpoints were recorded at different levels of biological organization, including lethal endpoints, morphological abnormalities, photomotor behavioral responses, cardiac activity, DNA damage and exposure level measurements (EROD activity, cyp1a and PAH metabolites). Neither morphological nor behavioral or physiological alterations were observed after exposure to Arabian Light fractions. In contrast, the Erika fractions led a high degree of toxicity in early life stages of zebrafish. Despite of defense mechanisms induced by oil, acute toxic effects have been recorded including mortality, delayed hatching, high rates of developmental abnormalities, disrupted locomotor activity and cardiac failures at the highest PAH concentrations (∑TPAHs=257,029±47,231ng·L(-1)). Such differences in toxicity are likely related to the oil composition. The use of developing zebrafish is a good tool to identify wide range of detrimental effects and elucidate their underlying foundations. Our work highlights once more, the cardiotoxic action (and potentially neurotoxic) of petroleum-related PAHs. PMID:27312275

  12. Validation and sensitivity comparisons of micro-scale toxicity tests for the evaluation of freshwater sediment toxicity

    SciTech Connect

    Riebel, P.; Bureau, J.; Blaise, C.; Michaud, J.R.

    1995-12-31

    A three-year study is currently underway to develop a representative and cost-effective battery of toxicity tests for evaluating freshwater sediment and porewater toxicity. Among the tests currently being evaluated are the following: Microtox{trademark} chronic test, Microtox{trademark} solid-phase test, Microtox{trademark} liquid phase test, Thamnotoxkit F{trademark}, Rotoxkit F{trademark}, Daphnia magna IQ test{trademark}, Sediment Toxkit, SOS Chromotest, a Selenastrum capricornutum short exposure assay, and trout hepatocyte assays. Conventional sediment tests with Chironomus tentans, Hyalella azteca and Lumbriculus variegatus, as well as benthic macroinvertebrate community assessments and sediment chemical characterizations are being conducted at two contaminated sites. Toxicity test reproducibility, sensitivity, practicality, cost and ecological relevance are discussed.

  13. Quality testing of three species of Tephritid fruit flies after embryo cryopreservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluates characteristics commonly used to define insect quality or fitness by using a complement of three species of tephritid fruit flies obtained from cryopreserved embryos. The Mexican, Anastrepah ludens, Caribbean, A. suspense, and Mediterranean, Certatitis capitata, fruit flies were...

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

    PubMed

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

    2010-12-15

    This investigation applied novel techniques for characterizing and fractionating nanosilver particles and aggregates and relating these measurements to toxicological endpoints. The acute toxicity of eight nanosilver suspensions of varying primary particle sizes (10-80 nm) and coatings (citrate, polyvinylpyrrolidone, EDTA, proprietary) was assessed using three aquatic test organisms (Daphnia magna, Pimephales promelas, Pseudokirchneriella subcapitata). When 48-h lethal median concentrations (LC50) were expressed as total silver, both D. magna and P. promelas were significantly more sensitive to ionic silver (Ag(+)) as AgNO(3) (mean LC50 = 1.2 and 6.3 μg/L, respectively) relative to a wide range in LC50 values determined for the nanosilver suspensions (2 -126 μg/L). However, when LC50 values for nanosilver suspensions were expressed as fractionated nanosilver (Ag(+) and/or <4 nm particles), determined by ultracentrifugation of particles and confirmed field-flow-fractograms, the LC50 values (0.3-5.6 μg/L) were comparable to the values obtained for ionic Ag(+) as AgNO(3). These results suggest that dissolved Ag(+) plays a critical role in acute toxicity and underscores the importance of characterizing dissolved fractions in nanometal suspensions.

  15. Thymoquinone therapy abrogates toxic effect of cadmium on rat testes.

    PubMed

    Fouad, A A; Jresat, I

    2015-05-01

    The protective effect of thymoquinone was investigated against cadmium-induced testicular toxicity in rats. Testicular toxicity was induced by a single intraperitoneal (i.p.) injection of cadmium chloride (2 mg kg(-1) ). Thymoquinone treatment (10 mg kg(-1)  day(-1) , i.p.) was applied for five consecutive days, starting 3 days before cadmium administration. Thymoquinone significantly attenuated the cadmium-induced decreases in serum testosterone, and testicular reduced glutathione and superoxide dismutase activity and significantly decreased the elevations of testicular malondialdehyde, nitric oxide and cadmium ion levels resulted from cadmium chloride administration. Also, thymoquinone ameliorated the cadmium-induced testicular tissue injury observed by histopathological examination. In addition, thymoquinone significantly decreased the cadmium-induced expression of inducible nitric oxide synthase, tumour necrosis factor-α, cyclooxygenase-2, nuclear factor-κB and caspase-3 in testicular tissue. It was concluded that thymoquinone, through its antioxidant and anti-inflammatory activities, may represent a potential candidate to protect the testes against the detrimental effect of cadmium exposure. PMID:24735446

  16. A review of the contribution of whole embryo culture to the determination of hazard and risk in teratogenicity testing.

    PubMed

    Webster, W S; Brown-Woodman, P D; Ritchie, H E

    1997-04-01

    Whole embryo culture appears to be an excellent method to screen chemicals for teratogenic hazard. Compared to in vivo testing it is cheap and rapid and does not involve experimentation on live adult animals. Also in the important area of risk estimation whole embryo culture offers distinct advantages over in vivo teratogenicity testing. Adverse embryonic outcomes (malformations or embryotoxicity) are directly related to the serum concentration of the compound being tested and can be compared to the serum concentration in the human. A similar comparison is not possible after in vivo testing because for most compounds there are major pharmacokinetic differences between humans and experimental animals. In vivo testing is also limited by the possibility that metabolites that occur in the human do not occur in the test animal. This problem can be overcome in the in vitro system by adding the metabolite directly at the desired concentration either with or without the parent compound. There is only one major disadvantage to in vitro testing and that is the limited period of embryogenesis that is undertaken in the commonly used culture system. This restricts the range of malformations that can be induced and may render the testing system unsuitable for compounds that are likely to exert their major toxicological effect late in gestation. Any evaluation of whole embryo culture for hazard and risk assessment in teratology must take into account the limited value of currently used in vivo methods. Over 2000 chemicals have been reported to be teratogenic in experimental animals exposed in vivo (Shepard, Catalog of Teratogenic Agents, 1989). In comparison only about 20 chemicals are known to cause birth defects in the human. This large number of in vivo false-positive cannot easily be distinguished from true-positives. In this respect in vivo testing is severely deficient. The embryo culture testing system would also be expected to produce many false-positives; but by

  17. Comparison of prehatch C-start responses in rainbow trout and lake trout embryos by means of a tactile stimulus test

    USGS Publications Warehouse

    Wright, P.J.; Noltie, Douglas B.; Tillitt, D.E.

    2003-01-01

    The C-start in teleost fishes, a type of startle response, mediates the ability to respond to abrupt, unexpected stimuli and is characterized by a short-latency, C-type fast start acceleration. In prehatch fish embryos, the C-start appears necessary for mechanical breakdown of the egg chorion and successful hatching by way of increased embryo movement and distribution of the hatching enzymes. In later stages, the C-start plays an important role in predator avoidance. Using tactile stimulation, we evaluated the C-start response in rainbow trout Oncorhynchus mykiss at 170 degree-days, when 6.6% of embryos exhibited C-starts, and lake trout Salvelinus namaycush embryos at 320 degree-days, when 23% of embryos exhibited C-starts. Triplicate groups of embryos were later tested at three developmental stages: early (220 and 360 degree-days for rainbow trout and lake trout, respectively), middle (260 and 480 degree-days, respectively), and late (320 and 560 degree-days, respectively). The proportion of trout embryos exhibiting C-start increased through time, such that 100% had responded by the late stage, just prior to hatching. C-starts could be obtained by repeated stimulation, and the relative activity of the embryos (based on the number of flexures per stimulus) also increased over time. Rainbow trout and lake trout showed very similar C-start responses at parallel developmental stages, and these patterns of response were similar to those reported in other fish species.

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

    SciTech Connect

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

    1995-12-31

    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 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 H4IIE 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 H4IIE 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 r{sup 2} 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.

  19. Multiple bio-analytical methods to reveal possible molecular mechanisms of developmental toxicity in zebrafish embryos/larvae exposed to tris(2-butoxyethyl) phosphate.

    PubMed

    Han, Zhihua; Wang, Qiangwei; Fu, Jie; Chen, Hongshan; Zhao, Ye; Zhou, Bingsheng; Gong, Zhiyuan; Wei, Si; Li, Jun; Liu, Hongling; Zhang, Xiaowei; Liu, Chunsheng; Yu, Hongxia

    2014-05-01

    The flame retardant tris(2-butoxyethyl) phosphate (TBEP) is a frequently detected contaminant in the environment, wildlife and human milk. The potentially toxic effects of TBEP and their underlying molecular mechanisms have not been elucidated. Here, zebrafish embryos were exposed to different concentrations of TBEP from 4 hours of post-fertilization (hpf) to 120 hpf, and effects on embryonic development and global protein expression patterns examined. Our results demonstrate that treatment with TBEP (0.8-100mg/L) causes a concentration- and time-dependent decrease in embryonic survival and the hatching percentage. The median lethal concentration was 10.7 mg/L at 120 hpf. Furthermore, exposure to 150 or 800 μg/L TBEP inhibited the degradation and utilization of vitellogenins and down-regulated the expression of proteins related to cation binding, and lipid transport, uptake and metabolism, accompanied by a decrease in heart rate and body length. Exposure to TBEP (150 or 800 μg/L) also decreased the expression of proteins involved in cell proliferation and DNA repair, and led to an increased number of apoptotic cells in the tail region. Collectively, our results suggest that exposure to TBEP causes toxicity in the developing zebrafish by inhibiting the degradation and utilization of nutrients from the mother and inducing apoptosis. PMID:24685621

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

    PubMed

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

    2013-08-01

    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) μgL(-1); M. galloprovincialis - 63 (36-94) μgL(-1); S. purpuratus - 74 (50-101) μgL(-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) μgL(-1); M. galloprovincialis - 172 (126-227) μgL(-1), S. purpuratus - 151 (129-177) μgL(-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

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

    PubMed

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

    2013-08-01

    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) μgL(-1); M. galloprovincialis - 63 (36-94) μgL(-1); S. purpuratus - 74 (50-101) μgL(-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) μgL(-1); M. galloprovincialis - 172 (126-227) μgL(-1), S. purpuratus - 151 (129-177) μgL(-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

  2. Formulated sediment for use in whole-sediment toxicity testing

    SciTech Connect

    Kemble, N.E.; Dwyer, F.J.; Hardesty, D.K.; Ingersoll, C.G.

    1995-12-31

    A formulated control sediment was developed to provide consistent and acceptable biological endpoints for a variety of species used in whole sediment toxicity testing. In an attempt to develop such a sediment the authors conducted multiple tests to evaluate: (1) {alpha}-cellulose as an organic carbon source, (2) various TOC concentrations, (3) various grain sizes, (4) different food types, and (5) overlying waters. Studies were conducted with the amphipod Hyalella azteca the midges Chironomus riparius, Chironomus tentans and the oligochaete Lumbriculus variegatus in 10 d exposures and H. azteca in 28 d exposures. Sediment from West Bearskin Lake Minnesota was used as a control sediment with each species in each test. Survival of test organisms in all of the 10-d experiments, with the exception of C. riparius, was above the acceptable levels for a control sediment. Survival in the formulated sediments also was not significantly different when compared to the control sediment. Amphipod survival in the 28-d exposures was low; however, the use of reconstituted water in combination with the formulated sediment may have been a problem. The authors are currently evaluating various types of overlying water with formulated sediments and sublethal endpoints in each of the exposures (i.e., growth, sexual maturation or head capsule width).

  3. [Comprehensive Toxicity Evaluation and Toxicity Identification Used in Tannery and Textile Wastewaters].

    PubMed

    Huang, Li; Chen, Wen-yan; Wan, Yu-shan; Zheng, Guo-juan; Zhao, Yuan; Cai, Qiang

    2015-07-01

    To better evaluate the toxicity of tannery and textile effluents from various emission stages, the research attempted battery of toxicological bioassays and toxicological indices. The bioassays employed Microtox test, zebra fish embryo-larval test and algae (Chlorella vulgaris) test. Meanwhile, toxicological indices including Toxicity Unit (TU), Average Toxicity (AvTx), Toxic Print (TxPr), Most Sensitive Test (MST) and Potential Ecotoxic Effects Probe (PEEP) were applied. The results illustrated that PEEP was the most comprehensive index to take account of the emissions and toxic potential of effluents. PEEP values showed that the reduction rates of toxicity in tannery and textile effluents were 36. 8% and 23. 2%, respectively. Finally, based on the Microtox toxicity test, toxicants in textile effluent were identified through the toxicity identification evaluation (TIE) studies. The results indicated that the main toxicant of textile effluent was non-polar organic pollutants, followed by filterable compounds, heavy metals, oxidizing substances and volatile components.

  4. Toxicity testing with the marine algae, Symbiodinium kawagutii (Dinophyceae)

    SciTech Connect

    Gorrie, J.R.; Bidwell, J.R.; Rippingale, R.J.

    1994-12-31

    The dinoflagellate, Symbiodinium kawagutii, is among the algal taxa which exist in symbiosis with a range of marine invertebrates. S. kawagutii is commonly found in association with the Hawaiian stony coral, Montipora verrucosa. The algae has been successfully cultured in the laboratory using a common marine algal growth media (Guillard f/2), and sufficient cell densities were achieved in a 96-hr bioassay to allow statistical evaluation of toxicity data. A 96-hr EC{sub 50} of 6.47 mg/L (95% C.I.: 3.54--9.88 mg/L) was calculated after exposure to potassium dichromate. Wide distribution of the coral host and ecological importance of the symbiosis make S. kawagutii an excellent candidate species for hazard evaluation in tropical marine ecosystems. Continuing research will seek to further refine the bioassay, including the use of a microplate technique for more rapid testing.

  5. Tigriopus fulvus: The interlaboratory comparison of the acute toxicity test.

    PubMed

    Faraponova, Olga; Giacco, Elisabetta; Biandolino, Francesca; Prato, Ermelinda; Del Prete, Francesco; Valenti, Alessandra; Sarcina, Stefania; Pasteris, Andrea; Montecavalli, Adele; Comin, Stefano; Cesca, Claudia; Francese, Marco; Cigar, Monica; Piazza, Veronica; Falleni, Fabrizio; Lacchetti, Ines

    2016-02-01

    The paper reports the results of an interlaboratory comparison involving 11 laboratories, with the objectives of apply and validate a new standardized ecotoxicological method on marine crustacean Tigriopus fulvus. Copper was chosen as reference toxicant as indicated in the official method. The results of two independent tests performed by all the participants, demonstrated that the new method is simple, fast and easy to learn. This is confirmed even by the values of z-score index calculated for each laboratory and the relative coefficient of variation (CV) which are 6.32% after 24h, 6.56 after 48h and 35.3% after 96h, mentioned in the ISO standards for the precision of interlaboratory assays. Therefore its use could be recommended in environmental studies and monitoring. PMID:26584461

  6. 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...

  7. 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...

  8. Evaluation of municipal waste incinerator fly ash toxicity and the role of cadmium by two aquatic toxicity tests

    SciTech Connect

    Kaneko, Hidehiro

    1996-12-31

    Fly ash from a municipal solid waste incinerator in Japan is regulated under the hazardous waste regulation Waste under Special Control, according to the Amendment of the Waste Disposal and Public Cleansing Law, because it contains high concentrations of heavy metals which are available for leaching. To evaluate the toxicity of fly ash, a fly ash leachate was prepared according to the Japanese standard leaching procedure. The chemical analysis of the leachate showed that possibly one of the most toxic substances was cadmium. The toxicity of the leachate and the cadmium was determined by algal assay and a Daphnia acute toxicity test. The results showed that the leachate was about seven times more toxic to the growth of algae and 20 to 30 times more toxic to the survival of Daphnia than expected from its cadmium concentration. The toxicity interaction between cadmium and the other constituents in the leachate was also examined. The toxicity of cadmium showed an additive effect with the other constituents in the leachate in algal assay. In the Daphnia test, however, cadmium showed an antagonistic effect.

  9. Toxicity testing of organic chemicals in groundwater polluted with landfill leachate

    SciTech Connect

    Baun, A.; Kloeft, L.; Bjerg, P.L.; Nyholm, N.

    1999-09-01

    A method for assessment of toxicity of nonvolatile organic chemicals contaminants in groundwater polluted with landfill leachate has been evaluated. The biotests utilized were composed of an algal growth inhibition test (Selenastrum capricornutum), a daphnia immobilization test (Daphnia magna), and a bacterial genotoxicity test (umuC, Salmonella typhimurium). The feasibility of the selected biotests was investigated for a series of groundwater samples collected along pollution gradients downstreams of two landfills in Jutland, Denmark. Two different approaches were used, direct toxicity testing of whole groundwater samples, and toxicity testing of concentrates obtained by solid-phase extraction. Direct testing of whole groundwater samples produced toxic responses, but the complex sample matrix masked the toxicity of the organic chemical contaminants of interest. Solid-phase extraction was used successfully as an on-site method that eliminated ion toxicity and produced biotest responses that reflected the toxicity of the nonvolatile organic chemical contaminants in the groundwater.

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  11. Aquatic toxicity testing for multicomponent compounds with special reference to preparation of test solution

    SciTech Connect

    Tadokoro, H.; Maeda, M.; Kawashima, Y.; Kitano, M.; Hwang, D.F.; Yoshida, T. )

    1991-02-01

    An adequate method of determining the toxicity of a compound consisting of multiple components, such as creosote, coal tar, and coal tar pitch, was studied for different test solution preparation methods, i.e., direct dosing without filtration, diluting the stock solution of saturated concentration, and dispersing with acetone. Killifish, Oryzias latipes, as a freshwater fish; red sea bream, Pagrus major, as a saltwater fish; and daphnia, Daphnia magna, as a representative crustacean, were used for testing. The chemical analysis of each preparation of test solution with gas chromatography revealed an entirely different profile of the components. The highest toxicity was obtained with preparation by acetone dispersion. That was followed by the preparations with direct dosing method and with the method of dilution of saturated concentration stock solution. Considering the results obtained, the direct dosing method with a suitable settling time may provide useful information enabling extrapolation of the test results to the natural environment for complex multicomponent compounds.

  12. Effects of the Particulate Matter2.5 (PM2.5) on Lipoprotein Metabolism, Uptake and Degradation, and Embryo Toxicity

    PubMed Central

    Kim, Jae-Yong; Lee, Eun-Young; Choi, Inho; Kim, Jihoe; Cho, Kyung-Hyun

    2015-01-01

    Particulate matter2.5 (PM2.5) is notorious for its strong toxic effects on the cardiovascular, skin, nervous, and reproduction systems. However, the molecular mechanism by which PM2.5 aggravates disease progression is poorly understood, especially in a water-soluble state. In the current study, we investigated the putative physiological effects of aqueous PM2.5 solution on lipoprotein metabolism. Collected PM2.5 from Seoul, Korea was dissolved in water, and the water extract (final 3 and 30 ppm) was treated to human serum lipoproteins, macrophages, and dermal cells. PM2.5 extract resulted in degradation and aggregation of high-density lipoprotein (HDL) as well as low-density lipoprotein (LDL); apoA-I in HDL aggregated and apo-B in LDL disappeared. PM2.5 treatment (final 30 ppm) also induced cellular uptake of oxidized LDL (oxLDL) into macrophages, especially in the presence of fructose (final 50 mM). Uptake of oxLDL along with production of reactive oxygen species was accelerated by PM2.5 solution in a dose-dependent manner. Further, PM2.5 solution caused cellular senescence in human dermal fibroblast cells. Microinjection of PM2.5 solution into zebrafish embryos induced severe mortality accompanied by impairment of skeletal development. In conclusion, water extract of PM2.5 induced oxidative stress as a precursor to cardiovascular toxicity, skin cell senescence, and embryonic toxicity via aggregation and proteolytic degradation of serum lipoproteins. PMID:26615830

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

    PubMed

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

    2013-03-19

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

  14. Genetically Defined Strains in Drug Development and Toxicity Testing.

    PubMed

    Festing, Michael F W

    2016-01-01

    There is growing concern about the poor quality and lack of repeatability of many pre-clinical experiments involving laboratory animals. According to one estimate as much as $28 billion is wasted annually in the USA alone in such studies. A decade ago the FDA's "Critical path" white paper noted that "The traditional tools used to assess product safety-animal toxicology and outcomes from human studies-have changed little over many decades and have largely not benefited from recent gains in scientific knowledge. The inability to better assess and predict product safety leads to failures during clinical development and, occasionally, after marketing." Repeat-dose 28-days and 90-days toxicity tests in rodents have been widely used as part of a strategy to assess the safety of drugs and chemicals but their repeatability and power to detect adverse effects have not been formally evaluated.The guidelines (OECD TG 407 and 408) for these tests specify the dose levels and number of animals per dose but do not specify the strain of animals which should be used. In practice, almost all the tests are done using genetically undefined "albino" rats or mice in which the genetic variation, a major cause of inter-individual and strain variability, is unknown and uncontrolled. This chapter suggests that a better strategy would be to use small numbers of animals of several genetically defined strains of mice or rats instead of the undefined animals used at present. Inbred strains are more stable providing more repeatable data than outbred stocks. Importantly their greater phenotypic uniformity should lead to more powerful and repeatable tests. Any observed strain differences would indicate genetic variation in response to the test substance, providing key data. We suggest that the FDA and other regulators and funding organizations should support research to evaluate this alternative. PMID:27150081

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

    PubMed

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

    2009-01-01

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

  16. Reproducibility of a life-cycle toxicity test with Daphnia magna

    SciTech Connect

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

    1981-01-01

    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)

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

    PubMed

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

    2011-05-01

    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 α and β 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 α and β 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 α 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

  18. Integrated testing strategies for toxicity employing new and existing technologies.

    PubMed

    Combes, Robert D; Balls, Michael

    2011-07-01

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

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

    PubMed

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

    2013-12-15

    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.

  20. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 28 2012-07-01 2012-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  1. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  2. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  3. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

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

    SciTech Connect

    Specht, W.L.

    1992-01-01

    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.

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

    EPA Science Inventory

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

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

    USGS Publications Warehouse

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

    1995-01-01

    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.

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

    PubMed

    Gura, Trisha

    2008-08-22

    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

  8. Rapid toxicity testing based on mitochondrial respiratory activity

    SciTech Connect

    Haubenstricker, M.E. ); Holodnick, S.E.; Mancy, K.H. ); Brabec, M.J. )

    1990-05-01

    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.

  9. Environmental concentrations of the cocaine metabolite benzoylecgonine induced sublethal toxicity in the development of plants but not in a zebrafish embryo-larval model.

    PubMed

    García-Cambero, J P; García-Cortés, H; Valcárcel, Y; Catalá, M

    2015-12-30

    Several studies have found cocaine and its main active metabolite benzoylecgonine (BE) in the aquatic environment and drinking water, derived from its consumption by humans as well as the inability of water treatment processes to eliminate it. A few studies have already investigated the ecotoxicology of BE to aquatic invertebrates, but none has still addressed the effects of BE on aquatic vertebrates or vascular plants. The goal of this publication is to provide information on the toxicity of environmental concentrations of BE during animal and vascular plant development, in order to contribute to a better understanding of the potential risk of this substance for the environment. BE induced alterations in mitochondrial activity and DNA levels of fern spores at environmental concentrations (1 ng L(-1)), which could disrupt gametophyte germination. However, BE at concentrations ranging from 1 ng L(-1) to 1 mg L(-1) did not disturb morphogenesis, hatching, heartbeat rate or larval motility in a zebrafish embryo-larval model. Adverse effects on ferns agree with the allelophathic role described for alkaloids and their unspecific interference with plant germination. Therefore, the anthropogenic dispersion of alkaloid allelochemicals may pose a risk for biodiversity and irrigated food production that should be further investigated. PMID:26340554

  10. Environmental concentrations of the cocaine metabolite benzoylecgonine induced sublethal toxicity in the development of plants but not in a zebrafish embryo-larval model.

    PubMed

    García-Cambero, J P; García-Cortés, H; Valcárcel, Y; Catalá, M

    2015-12-30

    Several studies have found cocaine and its main active metabolite benzoylecgonine (BE) in the aquatic environment and drinking water, derived from its consumption by humans as well as the inability of water treatment processes to eliminate it. A few studies have already investigated the ecotoxicology of BE to aquatic invertebrates, but none has still addressed the effects of BE on aquatic vertebrates or vascular plants. The goal of this publication is to provide information on the toxicity of environmental concentrations of BE during animal and vascular plant development, in order to contribute to a better understanding of the potential risk of this substance for the environment. BE induced alterations in mitochondrial activity and DNA levels of fern spores at environmental concentrations (1 ng L(-1)), which could disrupt gametophyte germination. However, BE at concentrations ranging from 1 ng L(-1) to 1 mg L(-1) did not disturb morphogenesis, hatching, heartbeat rate or larval motility in a zebrafish embryo-larval model. Adverse effects on ferns agree with the allelophathic role described for alkaloids and their unspecific interference with plant germination. Therefore, the anthropogenic dispersion of alkaloid allelochemicals may pose a risk for biodiversity and irrigated food production that should be further investigated.

  11. Chlormequat chloride retards rat embryo growth in vitro.

    PubMed

    Xiagedeer, Bayindala; Wu, Shuang; Liu, Yingjuan; Hao, Weidong

    2016-08-01

    Chlormequat chloride is the most widely used plant growth regulator in agriculture to promote sturdier growth of grain crops by avoidance of lodging. Therefore, human exposure to chlormequat chloride is very common, but its developmental toxicity has not been studied. Thus, we investigated the developmental toxicity of chlormequat chloride by applying rat whole embryo culture (WEC) model, limb bud micromass culture and 3T3 fibroblast cytotoxicity test. Chlormequat chloride at 150μg/ml (0.93mM) retarded the rat embryo growth without causing significant morphological malformations and at 500μg/ml (3.1mM) caused both retardation and morphological malformation of the embryos. However, the proliferation and differentiation of limb bud cells were not affected by chlormequat chloride at as high as up to 1000μg/ml (6.2mM) applied. This concentration of chlormequat chloride did not affect the cell viability as examined by 3T3 fibroblast cytotoxicity test either, suggesting that cellular toxicity may not play a role in chlormequat induced inhibition of rat embryo growth. Collectively, our results demonstrated that chlormequat chloride may affect embryo growth and development without inhibiting cell viability.

  12. [Thought and method of reproductive toxicity research in traditional Chinese medicine].

    PubMed

    Han, Jia-Yin; Yan, Yi; Liang, Ai-hua; Zhang, Yu-shi; Li, Chun-ying; Zhao, Yong; Lu, Yu-ting; Cui, Hong-yu; Li, Gui-qin

    2014-11-01

    Reproductive toxicity research takes an important place in traditional Chinese medicine pre-clinical safety evaluation. Modern reproductive toxicity experiment includes drug-related miscarriage, fetal death, teratism, and adverse effects on fertility, genital system, embryonic development and fetus, which is different from contraindicated in pregnancy in traditional Chinese medicine theory. Now the three-phases reproductive toxicity study is the method mainly applied in traditional Chinese medicine reproductive toxicity evaluation. Besides that, alternative methods of whole embryos culture and embryonic stem cell test are also used in traditional Chinese medicine embryo toxicity evaluation. This article reviews research progress and pre-clinical evaluation on reproductive toxicity of traditional Chinese medicine.

  13. Preimplantation Genetic Diagnosis: Prenatal Testing for Embryos Finally Achieving Its Potential

    PubMed Central

    Stern, Harvey J.

    2014-01-01

    Preimplantation genetic diagnosis was developed nearly a quarter-century ago as an alternative form of prenatal diagnosis that is carried out on embryos. Initially offered for diagnosis in couples at-risk for single gene genetic disorders, such as cystic fibrosis, spinal muscular atrophy and Huntington disease, preimplantation genetic diagnosis (PGD) has most frequently been employed in assisted reproduction for detection of chromosome aneuploidy from advancing maternal age or structural chromosome rearrangements. Major improvements have been seen in PGD analysis with movement away from older, less effective technologies, such as fluorescence in situ hybridization (FISH), to newer molecular tools, such as DNA microarrays and next generation sequencing. Improved results have also started to be seen with decreasing use of Day 3 blastomere biopsy in favor of polar body or Day 5 trophectoderm biopsy. Discussions regarding the scientific, ethical, legal and social issues surrounding the use of sequence data from embryo biopsy have begun and must continue to avoid concern regarding eugenic or inappropriate use of this technology. PMID:26237262

  14. Field validation of 10-day freshwater sediment toxicity tests using Hyalella azteca and Chironomus tentans

    SciTech Connect

    Becker, D.S.; Bigham, G.N.

    1995-12-31

    Two of the toxicity tests commonly used to evaluate freshwater sediments are the 10-day amphipod (Hyalella azteca) and chironomid (Chironomus tentans) tests. EPA and ASTM have recently developed standardized protocols for these tests. Although both tests are considered sensitive indicators of sediment toxicity, little information exists on how well test results correspond to adverse biological effects in the field. In this study, the lethal and sublethal (i.e., biomass) responses of the two toxicity tests were compared with alterations of benthic macroinvertebrate assemblages (i.e., benthic effects) at 56 stations in Onondaga Lake, New York. The lake has received municipal and industrial discharges for more than 100 years, and sediment chemical concentrations range widely throughout the lake. Toxicity results for Onondaga Lake were compared with reference conditions using the t-test, and benthic effects were determined using classification analysis of log-transformed taxa abundances. In general, a relatively high level of agreement was found between results of the toxicity tests and alterations of benthic assemblages. Significant (P < 0.05) correlations were found between all toxicity test endpoints and taxa richness of benthic assemblages. In addition, significant concordance (P {le} 0.01, binomial test) was found between toxicity designations for the 56 stations based on toxicity tests and toxicity designations based on benthic effects. Despite the general level of agreement among the various biological indicators, chironomid biomass and benthic effects were found to be the most sensitive indicators of toxicity, whereas amphipod survival and biomass were the least sensitive indicators. This study suggests that results of the 10-day amphipod and chironomid toxicity tests are highly predictive of adverse biological effects in the field.

  15. Applicability of ambient toxicity testing to national or regional water-quality assessment

    USGS Publications Warehouse

    Elder, John F.

    1990-01-01

    Comprehensive assessment of the quality of natural waters requires a multifaceted approach. Descriptions of existing conditions may be achieved by various kinds of chemical and hydrologic analyses, whereas information about the effects of such conditions on living organisms depends on biological monitoring. Toxicity testing is one type of biological monitoring that can be used to identify possible effects of toxic contaminants. Based on experimentation designed to monitor responses of organisms to environmental stresses, toxicity testing may have diverse purposes in water-quality assessments. These purposes may include identification of areas that warrant further study because of poor water quality or unusual ecological features, verification of other types of monitoring, or assessment of contaminant effects on aquatic communities. Toxicity-test results are most effective when used as a complement to chemical analyses, hydrologic measurements, and other biological monitoring. However, all toxicity-testing procedures have certain limitations that must be considered in developing the methodology and applications of toxicity testing in any large-scale water-quality-assessment program. A wide variety of toxicity-test methods have been developed to fulfill the needs of diverse applications. The methods differ primarily in the selections made relative to four characteristics: (1) test species, (2) endpoint (acute or chronic), (3) test-enclosure type, and (4) test substance (toxicant) that functions as the environmental stress. Toxicity-test approaches vary in their capacity to meet the needs of large-scale assessments of existing water quality. Ambient testing, whereby the test organism is exposed to naturally occurring substances that contain toxicant mixtures in an organic or inorganic matrix, is more likely to meet these needs than are procedures that call for exposure of the test organisms to known concentrations of a single toxicant. However, meaningful

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

    ERIC Educational Resources Information Center

    Vollmer, John J.; And Others

    1987-01-01

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

  17. A test strategy for the assessment of additive attributed toxicity of tobacco products.

    PubMed

    Kienhuis, Anne S; Staal, Yvonne C M; Soeteman-Hernández, Lya G; van de Nobelen, Suzanne; Talhout, Reinskje

    2016-08-01

    The new EU Tobacco Product Directive (TPD) prohibits tobacco products containing additives that are toxic in unburnt form or that increase overall toxicity of the product. This paper proposes a strategy to assess additive attributed toxicity in the context of the TPD. Literature was searched on toxicity testing strategies for regulatory purposes from tobacco industry and governmental institutes. Although mainly traditional in vivo testing strategies have been applied to assess toxicity of unburnt additives and increases in overall toxicity of tobacco products due to additives, in vitro tests combined with toxicogenomics and validated using biomarkers of exposure and disease are most promising in this respect. As such, tests are needed that are sensitive enough to assess additive attributed toxicity above the overall toxicity of tobacco products, which can associate assay outcomes to human risk and exposure. In conclusion, new, sensitive in vitro assays are needed to conclude whether comparable testing allows for assessment of small changes in overall toxicity attributed to additives. A more pragmatic approach for implementation on a short-term is mandated lowering of toxic emission components. Combined with risk assessment, this approach allows assessment of effectiveness of harm reduction strategies, including banning or reducing of additives.

  18. 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...

  19. Toxicity of 8-Hydroxyquinoline in Cryprinus carpio Using the Acute Toxicity Test, Hepatase Activity Analysis and the Comet Assay.

    PubMed

    Yan, Shuaiguo; Chen, Lili; Dou, Xiaofei; Qi, Meng; Du, Qiyan; He, Qiaoqiao; Nan, Mingge; Chang, Zhongjie; Nan, Ping

    2015-08-01

    To evaluate the environmental toxicity of 8-hydroxyquinoline (8-HOQ), an important industrial raw material found in China's major ornamental fish, Cryprinus carpio, using the acute toxicity test, hepatase activity analysis and the comet assay. The results indicated that 8-HOQ had significant acute toxicity in adult C. carpio with a 96 h-LC50 of 1.15 and 0.22 mg L(-1) hepatic quinoline residues as assessed by HPLC. 8-HOQ also induced genotoxicity in the form of strand breaks in the DNA of hepatic cells as shown by the comet assay. With regard to physiological toxicity, 8-HOQ induced a decrease in the activities of hepatic GOT and GPT with increased exposure concentration and time. These data suggest that 8-HOQ may be toxic to the health of aquatic organisms when accidentally released into aquatic ecosystems. The data also suggest that the comet assay may be used in biomonitoring to determine 8-HOQ genotoxicity and hepatic GPT and GOT activities may be potential biomarkers of physiological toxicity.

  20. Toxicity of 8-Hydroxyquinoline in Cryprinus carpio Using the Acute Toxicity Test, Hepatase Activity Analysis and the Comet Assay.

    PubMed

    Yan, Shuaiguo; Chen, Lili; Dou, Xiaofei; Qi, Meng; Du, Qiyan; He, Qiaoqiao; Nan, Mingge; Chang, Zhongjie; Nan, Ping

    2015-08-01

    To evaluate the environmental toxicity of 8-hydroxyquinoline (8-HOQ), an important industrial raw material found in China's major ornamental fish, Cryprinus carpio, using the acute toxicity test, hepatase activity analysis and the comet assay. The results indicated that 8-HOQ had significant acute toxicity in adult C. carpio with a 96 h-LC50 of 1.15 and 0.22 mg L(-1) hepatic quinoline residues as assessed by HPLC. 8-HOQ also induced genotoxicity in the form of strand breaks in the DNA of hepatic cells as shown by the comet assay. With regard to physiological toxicity, 8-HOQ induced a decrease in the activities of hepatic GOT and GPT with increased exposure concentration and time. These data suggest that 8-HOQ may be toxic to the health of aquatic organisms when accidentally released into aquatic ecosystems. The data also suggest that the comet assay may be used in biomonitoring to determine 8-HOQ genotoxicity and hepatic GPT and GOT activities may be potential biomarkers of physiological toxicity. PMID:26067700

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

    SciTech Connect

    Simbeck, D.J.

    1997-06-01

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

  2. Evaluation of three soil toxicity tests used to monitor acceptable endpoints

    SciTech Connect

    Brinkmann, M.; Stroo, H.; Leuschner, A.; Leuteritz, D.; Stromberg, M.; Brourman, M.

    1995-12-31

    Three terrestrial toxicity tests were used to evaluate the efficacy of biological treatment of creosote and pentachlorophenol impacted soils at a Superfund site. Microtox, 5-day lettuce seed, and 14-day earthworm toxicity tests were performed on 10 soil samples at the beginning and end of 3 months of land treatment. Secondary endpoints of root length and earthworm weight loss were also evaluated. EC50 and LC50 values were calculated using a Trimmed Logit Statistical Program and compared to toxicity of 10 background samples collected from the site. Results for initial soils demonstrated toxicity with three of the five endpoints. End treatment results showed no measurable toxicity using all endpoints. Toxicity testing results are critical for obtaining regulatory approval for the full-scale treatment system. Post treatment closure requirements for the site will be based on bioassay results. Evaluation of the three tests used showed the Microtox test to be the most sensitive to this type of toxicity. Lettuce seed germination results were the least sensitive of the three primary endpoints chosen. Of the secondary endpoint criteria, root length demonstrated reliable EC50 values and showed toxicity trends similar to Microtox and earthworm tests. The earthworm weight loss endpoint was not a useful toxicity measurement at 14 days.

  3. Factors affecting toxicity test endpoints in sensitive life stages of native Gulf of Mexico species.

    PubMed

    Echols, B S; Smith, A J; Rand, G M; Seda, B C

    2015-05-01

    Indigenous species are less commonly used in laboratory aquatic toxicity tests compared with standard test species due to (1) limited availability lack of requisite information necessary for their acclimation and maintenance under laboratory conditions and (2) lack of information on their sensitivity and the reproducibility of toxicity test results. As part of the Natural Resource Damage Assessment aquatic toxicity program in response to the Deepwater Horizon Oil incident (2010), sensitive life stages of native Gulf of Mexico species were evaluated in laboratory toxicity tests to determine the potential effects of the spill. Fish (n = 5) and invertebrates (n = 2) selected for this program include the following: the Florida pompano (Trachinotus carolinus), red drum (Sciaenops ocellatus), spotted sea trout (Cynoscion nebulosus), cobia (Rachycentron canadum), red porgy (Pagrus pagrus), blue crab (Callinectes sapidus), and the common moon jellyfish (Aurelia aurita). Initially in the program, to establish part of the background information, acute tests with reference toxicants (CdCl2, KCl, CuSO4) were performed with each species to establish data on intraspecies variability and test precision as well as identify other factors that may affect toxicity results. Median lethal concentration (LC50) values were calculated for each acute toxicity test with average LC50 values ranging from 248 to 862 mg/L for fish exposures to potassium chloride. Variability between test results was determined for each species by calculating the coefficient of variation (%CV) based on LC50 values. CVs ranged from 11.2 % for pompano (96-h LC50 value) to 74.8 % for red porgy 24-h tests. Cadmium chloride acute toxicity tests with the jellyfish A. aurita had the lowest overall CV of 3.6 %. By understanding acute toxicity to these native organisms from a compound with known toxicity ranges and the variability in test results, acute tests with nonstandard species can be better interpreted and used

  4. Factors affecting toxicity test endpoints in sensitive life stages of native Gulf of Mexico species.

    PubMed

    Echols, B S; Smith, A J; Rand, G M; Seda, B C

    2015-05-01

    Indigenous species are less commonly used in laboratory aquatic toxicity tests compared with standard test species due to (1) limited availability lack of requisite information necessary for their acclimation and maintenance under laboratory conditions and (2) lack of information on their sensitivity and the reproducibility of toxicity test results. As part of the Natural Resource Damage Assessment aquatic toxicity program in response to the Deepwater Horizon Oil incident (2010), sensitive life stages of native Gulf of Mexico species were evaluated in laboratory toxicity tests to determine the potential effects of the spill. Fish (n = 5) and invertebrates (n = 2) selected for this program include the following: the Florida pompano (Trachinotus carolinus), red drum (Sciaenops ocellatus), spotted sea trout (Cynoscion nebulosus), cobia (Rachycentron canadum), red porgy (Pagrus pagrus), blue crab (Callinectes sapidus), and the common moon jellyfish (Aurelia aurita). Initially in the program, to establish part of the background information, acute tests with reference toxicants (CdCl2, KCl, CuSO4) were performed with each species to establish data on intraspecies variability and test precision as well as identify other factors that may affect toxicity results. Median lethal concentration (LC50) values were calculated for each acute toxicity test with average LC50 values ranging from 248 to 862 mg/L for fish exposures to potassium chloride. Variability between test results was determined for each species by calculating the coefficient of variation (%CV) based on LC50 values. CVs ranged from 11.2 % for pompano (96-h LC50 value) to 74.8 % for red porgy 24-h tests. Cadmium chloride acute toxicity tests with the jellyfish A. aurita had the lowest overall CV of 3.6 %. By understanding acute toxicity to these native organisms from a compound with known toxicity ranges and the variability in test results, acute tests with nonstandard species can be better interpreted and used

  5. Wheat seed embryo excision enables the creation of axenic seedlings and Koch’s postulates testing of putative bacterial endophytes

    PubMed Central

    Robinson, Rebekah J.; Fraaije, Bart A.; Clark, Ian M.; Jackson, Robert W.; Hirsch, Penny R.; Mauchline, Tim H.

    2016-01-01

    Early establishment of endophytes can play a role in pathogen suppression and improve seedling development. One route for establishment of endophytes in seedlings is transmission of bacteria from the parent plant to the seedling via the seed. In wheat seeds, it is not clear whether this transmission route exists, and the identities and location of bacteria within wheat seeds are unknown. We identified bacteria in the wheat (Triticum aestivum) cv. Hereward seed environment using embryo excision to determine the location of the bacterial load. Axenic wheat seedlings obtained with this method were subsequently used to screen a putative endophyte bacterial isolate library for endophytic competency. This absence of bacteria recovered from seeds indicated low bacterial abundance and/or the presence of inhibitors. Diversity of readily culturable bacteria in seeds was low with 8 genera identified, dominated by Erwinia and Paenibacillus. We propose that anatomical restrictions in wheat limit embryo associated vertical transmission, and that bacterial load is carried in the seed coat, crease tissue and endosperm. This finding facilitates the creation of axenic wheat plants to test competency of putative endophytes and also provides a platform for endophyte competition, plant growth, and gene expression studies without an indigenous bacterial background. PMID:27151146

  6. New technologies and approaches in toxicity testing and risk assessment (ESOT)

    EPA Science Inventory

    The release of the National Research Council’s Report “Toxicity Testing in the 21st Century: A Vision and a Strategy” in 2007 initiated a broad-based movement in the toxicology community to re-think how toxicity testing and risk assessment are performed. Multiple efforts in the ...

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

    EPA Science Inventory

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

  8. Strategies for integrating transcriptional profiling into high throughput toxicity testing (SOT Symposium Workshop presentation)

    EPA Science Inventory

    Presentation Description: The release of the National Research Council’s Report “Toxicity Testing in the 21st Century: A Vision and a Strategy” in 2007 initiated a broad-based movement in the toxicology community to re-think how toxicity testing and risk assessment are performed....

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

    PubMed Central

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

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the “toxic potential” of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed. PMID:27667986

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the "toxic potential" of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed. PMID:27667986

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

    SciTech Connect

    Nacci, D.; Gleason, T.; Munns, W.R. Jr.

    1995-12-31

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

  14. Terrestrial isopods -- a good choice for toxicity testing of pollutants in the terrestrial environment

    SciTech Connect

    Drobne, D.

    1997-06-01

    Terrestrial isopods are suitable invertebrates for testing the relative toxicities of chemicals present in the terrestrial environment. Terrestrial isopods respond in numerous ways to elevated concentrations of chemicals in their food, but only a few of these responses can be used as toxicological endpoints. The most suitable are changes in reproduction, food consumption, moult cycle duration, and structure of the digestive glands. These responses are able to provide accurate indications of sublethal toxicity. Toxicity tests with terrestrial isopods could be much more reliable through the use of positive controls. A positive control with a reference toxicant could also be supplemented by a reference endpoint. The most suitable reference endpoint is change of food consumption rate. Toxicity testing with terrestrial isopods is a very promising method for fast, routine, and inexpensive laboratory determination of the relative toxicities of chemicals in the terrestrial environment.

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

    SciTech Connect

    Hooten, R.; Carr, R.S.

    1995-12-31

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

  16. 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...

  17. 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...

  18. Application of simple and low-cost toxicity tests for ecotoxicological assessment of industrial wastewaters.

    PubMed

    Aydin, Mehmet Emin; Aydin, Senar; Tongur, Süheyla; Kara, Gülnihal; Kolb, Marit; Bahadir, Müfit

    2015-01-01

    The objective of this study was to identify and to apply appropriate biotests having the advantages of being highly sensitive, easy to run, relatively inexpensive and able to substitute fish toxicity tests due to ethical reasons of animal welfare. To perform an ecotoxicological assessment of industrial wastewaters, different microbiotests were conducted to substitute the fish toxicity test with Lebistes reticulatus through Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, Lemna minor and Lepidium sativum representing different trophic levels in the aquatic and terrestrial ecosystems. Also, Algaltox F(TM) with Pseudokirchneriella subcapitata and Protox F(TM) with Tetrahymena thermophila tests were carried out. However, they could not be applied successfully for the wastewater samples. Wastewater samples from seven different industrial zones comprising different industries were subjected to characterization through measuring their physical-chemical parameters and their toxicity versus the above-mentioned organisms. T. platyurus, D. magna and L. reticulatus were the most sensitive test organisms investigated for the wastewaters. Considering toxic unit values, generally wastewater samples were toxic according to Thamnotox F(TM), Daphtox F(TM) and fish toxicity tests. As an important outcome, it was concluded that Daphtox F(TM) and Thamnotox F(TM) could be a good alternative for the fish toxicity test, which is so far the sole toxicity test accepted by the Turkish Water Pollution Control Regulation. PMID:25951939

  19. Toxicity of polybrominated diphenyl ethers (de-71) in chicken (Gallus gallus), mallard (Anas platyrhynchos), and American kestrel (Falco sparverius) embryos and hatchlings

    USGS Publications Warehouse

    McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

    2009-01-01

    Embryonic survival, pipping and hatching success, and sublethal biochemical, endocrine, and histological endpoints were examined in hatchling chickens (Gallus gallus), mallards (Anas platyrhynchos), and American kestrels (Falco sparverius) following air cell administration of a pentabrominated diphenyl ether (penta-BDE; DE-71) mixture (0.01-20 mu g/g egg) or polychlorinated biphenyl (PCB) congener 126 (3,3', 4,4', 5-pentachlorobiphenyl; 0.002 mu g/g egg). The penta-BDE decreased pipping and hatching success at concentrations of 10 and 20 mu g/g egg in kestrels but had no effect on survival endpoints in chickens or mallards. Sublethal effects in hatchling chickens included ethoxyresorufin-O-dealkylase (EROD) induction and histological changes in the bursa, but these responses were not observed in other species. Polychlorinated biphenyl congener 126 (positive control) reduced survival endpoints in chicken and kestrel embryos and caused sublethal effects (EROD induction, reduced bursal mass and follicle size) in chickens. Mallards were clearly less sensitive than the other species to administered penta-BDE and PCB 126. In a second experiment, the absorption of penta-BDE (11.1 mu g/g egg, air cell administered during early development) into the contents of chicken and kestrel eggs was determined at various intervals (24 h postinjection, midincubation, and pipping). By pipping, 29% of the penta-BDE administered dose was present in the egg contents in chickens, and 18% of the administered dose was present in kestrel egg contents. Based on uptake in kestrels, the lowest-observed-effect level on pipping and hatching success may be as low as 1.8 mu g total penta-BDE/g egg, which approaches concentrations detected in eggs of free-ranging birds. Because some penta-BDE congeners are still increasing in the environment, the toxic effects observed in the present study are cause for concern in wildlife.

  20. 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...

  1. Effect of the test media and toxicity of LAS on the growth of Isochrysis galbana.

    PubMed

    Garrido-Perez, M C; Perales-VargasMachuca, J A; Nebot-Sanz, E; Sales-Márquez, D

    2008-11-01

    In this paper, the toxicity of linear alkylbenzene sulfonate (LAS) was evaluated in the marine microalga Isochrysis galbana using data of growth inhibition toxicity tests at 96-h exposure time. Toxicity was examined in standard conditions and by means of the modification of two variables of the test media: (1) the dilution water and (2) the content of nutrients in the test medium. For this purpose, a total of 10 toxicity test were designed: five dilution waters, four natural marine waters and one synthetic seawater; each in two different nutritive conditions, saturated nutrient concentration (SC) by the addition of modified f/2 nutritive medium, and natural nutrient concentration (NC), i.e., without the addition of f/2. At threshold toxicity levels, the dilution waters used in the test and the nutrient concentrations did not affect the toxicity of LAS. At IC50 concentrations, the toxicity of LAS is influenced by both variables: under SC conditions, the toxic effect of LAS diminishes, obtaining in all the tests IC50 > 10 mg/L LAS. Under NC conditions, IC50 concentrations ranging between 3.15 and 9.26 mg/L LAS have been obtained.

  2. [Toxicity tests and their application in safety assessment of water quality].

    PubMed

    Xu, Jian-Ying; Zhao, Chun-Tao; Wei, Dong-Bin

    2014-10-01

    The safety of water quality has important impacts not only on the health of ecological system, but also on the survival and development of human beings. The conventional assessment methods for water quality based on the concentration limits are not reliable. The toxicity tests can vividly reflect the whole adverse biological effects of multiple chemicals in water body, which has been regarded as a necessary supplement for conventional water quality assessment methods based on physicochemical parameters. Considering the chemical pollutants usually have various adverse biological effects, the ecotoxicity testing methods, including lethality, genotoxicity, endocrine disrupting effects, were classified according to the different toxicity types. Then, the potential applications of toxicity testing methods and corresponding evaluation indices in evaluating the toxicity characteristics of ambient water samples were discussed. Particularly, the safety assessment methods for water quality based on the toxicity tests, including potential toxicology, toxicity unit classification system, potential ecotoxic effect probe, and safety assessment of water quality based on toxicity test battery, were summarized. This paper not only systematically reviewed the progress of toxicity tests and their application in safety assessment of water quality, but also provided the scientific basis for the further development in the future.

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

    USGS Publications Warehouse

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

    1996-01-01

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

  4. Pilot study for ambient toxicity testing in Chesapeake bay. Year two report

    SciTech Connect

    Hall, L.W.; Ziegenfuss, M.C.; Fischer, S.A.; Anderson, R.D.; Killen, W.D.

    1992-11-01

    The primary goal of the ambient toxicity testing pilot study was to identify toxic areas in living resource habitats of the Chesapeake Bay watershed by using a battery of standardized, directly modified or recently developed water column, sediment and suborganismal toxicity tests. Tests were conducted twice at the following stations: Potomac River-Morgantown, Potomac River-Dahlgren, Patapsco River and Wye River. A suite of inorganic and organic contaminants was evaluated in the water column and sediment during these tests. Standard water quality conditions were also evaluated in water and sediment from all stations.

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

    SciTech Connect

    Erickson, W.P.; McDonald, L.L.

    1995-07-01

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

  6. Microfluidic EmbryoSort technology: towards in flow analysis, sorting and dispensing of individual vertebrate embryos

    NASA Astrophysics Data System (ADS)

    Fuad, Nurul M.; Wlodkowic, Donald

    2013-12-01

    The demand to reduce the numbers of laboratory animals has facilitated the emergence of surrogate models such as tests performed on zebrafish (Danio rerio) or African clawed frog's (Xenopus levis) eggs, embryos and larvae. Those two model organisms are becoming increasingly popular replacements to current adult animal testing in toxicology, ecotoxicology and also in drug discovery. Zebrafish eggs and embryos are particularly attractive for toxicological analysis due their size (diameter 1.6 mm), optical transparency, large numbers generated per fish and very straightforward husbandry. The current bottleneck in using zebrafish embryos for screening purposes is, however, a tedious manual evaluation to confirm the fertilization status and subsequent dispensing of single developing embryos to multitier plates to perform toxicity analysis. Manual procedures associated with sorting hundreds of embryos are very monotonous and as such prone to significant analytical errors due to operator's fatigue. In this work, we present a proofof- concept design of a continuous flow embryo sorter capable of analyzing, sorting and dispensing objects ranging in size from 1.5 - 2.5 mm. The prototypes were fabricated in polymethyl methacrylate (PMMA) transparent thermoplastic using infrared laser micromachining. The application of additive manufacturing processes to prototype Lab-on-a-Chip sorters using both fused deposition manufacturing (FDM) and stereolithography (SLA) were also explored. The operation of the device was based on a revolving receptacle capable of receiving, holding and positioning single fish embryos for both interrogation and subsequent sorting. The actuation of the revolving receptacle was performed using a DC motor and/or microservo motor. The system was designed to separate between fertilized (LIVE) and non-fertilized (DEAD) eggs, based on optical transparency using infrared (IR) emitters and receivers.

  7. 40 CFR 795.120 - Gammarid acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., lowest and middle test concentrations. (v) The test duration is 96 hours. The test is unacceptable if.... (C) Gammarids used in a particular test shall be of similar age and/or size and from the same...

  8. 40 CFR 795.120 - Gammarid acute toxicity test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., lowest and middle test concentrations. (v) The test duration is 96 hours. The test is unacceptable if.... (C) Gammarids used in a particular test shall be of similar age and/or size and from the same...

  9. 40 CFR 795.120 - Gammarid acute toxicity test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... definitions also apply to this guideline: Death means the lack of reaction of a test organism to gentle... dilution water through each chamber is adjusted to the rate desired. In a static test, the test substance is introduced into each test chamber. In a flow-through test, the rate in which the test substance...

  10. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... construction materials, test chambers, and testing apparatus to dilution water or to test solutions prior to... tank with no recycling. (7) Incipient LC 50 means that test substance concentration, calculated from... substance. (F) A test substance delivery system for flow-through tests. (ii) Construction...

  11. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... construction materials, test chambers, and testing apparatus to dilution water or to test solutions prior to... tank with no recycling. (7) Incipient LC 50 means that test substance concentration, calculated from... substance. (F) A test substance delivery system for flow-through tests. (ii) Construction...

  12. Cell cultures are more sensitive than Saccharamoyces cervisiae tests for assessing the toxicity of aquatic pollutants

    SciTech Connect

    Mochida, K.; Gomyoda, M.; Fujita, T.; Yamagata, K.

    1988-07-01

    Cultured fish and human cells have been used as bioassay systems for the evaluation of the toxicity of aquatic pollutants. Numerous assays using bacteria and yeast have also been used for such purposes. The authors report the toxicity of aquatic pollutants (Cd, Hg, and Ni), using cell culture systems and the yeast Saccharomyces cervisiae test. Cd, Hg, and Ni were chosen as model compounds of pollutants because the related toxicity is now fairly well established.

  13. Assessment of four different test designs for Hyalella azteca 10 days sediment toxicity test

    SciTech Connect

    Ramirez-Romero, P. |; Oris, J.T.; Bailer, J.; DePoy, M.

    1995-12-31

    The purpose of this study was to assess the adequacy of four experimental designs of the Hyalella azteca 10 days sediment toxicity test. The authors conducted a series of sediment toxicity tests using an EPA recommended experimental design (8 chambers with 10 organisms per treatment) and three other designs. These had the same total number of organisms (80) per treatment and the same sediment:water ratio (1:1.5) but different number of chambers (4,2,1). The number of organisms recovered, the time to sort and count the animals, as well as the time to make a water change were compared for these four designs. Logistic regression was used to analyze the recovery data while one-way analysis of variance methods were used to analyze the time responses. The results showed that the four treatments were comparable in terms of proportion of organisms recovered. However, the sorting time and the water change time decreased as the number of chambers decreased, making those designs with less chambers more desirable.

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

    USGS Publications Warehouse

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

    1996-01-01

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

  15. Studies with the USF/NASA toxicity screening test method - Oxygen concentrations with various test conditions

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

    Continuing efforts to increase the versatility of the USF/NASA toxicity screening test method have included the use of different test conditions in order to simulate various fire environments. The use of air flow at flow rates of 16 to 48 ml/sec maintains oxygen concentrations above 19 percent throughout the 30 min exposure period, compared to above 16 percent without forced air flow. These levels of oxygen are well within the tolerance range of mice, and approach the oxygen levels found in many real fire situations. Proposed minimum oxygen levels based on experience with rats are unduly restrictive on the use of other species such as mice, and tend to eliminate the cost savings which may more than justify the selection of mice.

  16. Concentration-time data in toxicity tests and resulting relationships

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    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.

  17. Relationships between exposure and dose in aquatic toxicity tests for organic chemicals.

    PubMed

    Mackay, Donald; McCarty, Lynn S; Arnot, Jon A

    2014-09-01

    There is continuing debate about the merits of exposure-based toxicity metrics such as median lethal concentration (LC50) versus organism-based metrics such as critical body residue (CBR) as indicators of chemical toxicity to aquatic organisms. To demonstrate relationships and differences between these 2 metrics, the authors applied a simple one-compartment toxicokinetic mass-balance model for water-exposed fish for a series of hypothetical organic chemicals exhibiting baseline narcotic toxicity. The authors also considered the influence of several toxicity-modifying factors. The results showed that the results of standard toxicity tests, such as the LC50, are strongly influenced by several modifying factors, including chemical and organism characteristics such as hydrophobicity, body size, lipid content, metabolic biotransformation, and exposure durations. Consequently, reported LC50s may not represent consistent dose surrogates and may be inappropriate for comparing the relative toxicity of chemicals. For comparisons of toxicity between chemicals, it is preferable to employ a delivered dose metric, such as the CBR. Reproducible toxicity data for a specific combination of chemical, exposure conditions, and organism can be obtained only if the extent of approach to steady state is known. Suggestions are made for revisions in test protocols, including the use of models in advance of empirical testing, to improve the efficiency and effectiveness of tests and reduce the confounding influences of toxicity-modifying factors, especially exposure duration and metabolic biotransformation. This will assist in linking empirical measurements of LC50s and CBRs, 2 different but related indicators of aquatic toxicity, and thereby improve understanding of the large existing database of aquatic toxicity test results.

  18. Development and evaluation of multispecies test protocols for assessing chemical toxicity

    SciTech Connect

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

    1985-06-01

    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)

  19. Alternative testing systems for evaluating noncarcinogenic, hematologic toxicity.

    PubMed Central

    Parchment, R E

    1998-01-01

    Hematopoietic tissues are the targets of numerous xenobiotics. Clinical hematotoxicity is either a decrease or an increase in peripheral blood cell counts in one or more cell lineages--a cytopenia or a cytosis, respectively--that carries a risk of an adverse clinical event. The purpose of in vitro hematotoxicology is the prediction of these adverse hematologic effects from the effects of the toxicants on human hematopoietic targets under controlled experimental conditions in the laboratory. Building on its important foundations in experimental hematology and the wealth of hematotoxicology data found in experimental oncology, this field of alternative toxicology has developed rapidly during the past decade. Although the colony-forming unit-granulocyte/monocyte neutrophil progenitor is most frequently evaluated, other defined progenitors and stem cells as well as cell types found in the marrow stroma can be evaluated in vitro. End points have been proposed for predicting toxicant exposure levels at the maximum tolerated dose and the no observable adverse effect level for the neutrophil lineage, and several clinical prediction models for neutropenia have developed to the point that they are ready for prospective evaluation and validation in both preclinical species and humans. Known predictive end points are the key to successful comparisons across species or across chemical structures when in vitro dose-response curves are nonparallel. Analytical chemistry support is critical for accurate interpretation of in vitro data and for relating the in vitro pharmacodynamics to the in vivo pharmacokinetics. In contrast to acute neutropenia, anemia and acute thrombocytopenia, as well as adverse effects from chronic toxicant exposure, are much more difficult to predict from in vitro data. Pharmacologic principles critical for clinical predictions from in vitro data very likely will apply to toxicities to other proliferative tissues, such as mucositis. PMID:9599702

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

    SciTech Connect

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

    1997-09-01

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

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

    PubMed

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

    2016-06-01

    Fungicide azoxystrobin toxicity was monitored by means of a 96-h biotest with Artemia franciscana nauplius stages after exposure to solutions with concentrations of 0.2, 0.4, 0.6 and 0.8 mg L(-1) irradiated with (60)Co gamma radiation with doses of 1, 2.5, 5 and 10 kGy. The effects of ionization radiation on azoxystrobin toxicity were mainly manifested by a statistically significant reduction of lethality after 72- and 96-h exposure. A maximum reduction of lethality of 72 % was achieved using doses of 1-5 kGy for an azoxystrobin initial concentration of 0.4 mg L(-1) and after 72 h of exposure. At a 96-h exposure, a difference of lethal effects reached up to 70 % for a dose of 10 kGy. The observed effect of gamma ionizing radiation on azoxystrobin toxicity suggest that this approach can be applied as an alternative for a reduction of azoxystrobin residua in food. PMID:27107585

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

    PubMed

    Kroese, E Dinant; Bosgra, Sieto; Buist, Harrie E; Lewin, Geertje; van der Linden, Sander C; Man, Hai-yen; Piersma, Aldert H; Rorije, Emiel; Schulpen, Sjors H W; Schwarz, Michael; Uibel, Frederik; van Vugt-Lussenburg, Barbara M A; Wolterbeek, Andre P M; van der Burg, Bart

    2015-08-01

    Previously we showed a battery consisting of CALUX transcriptional activation assays, the ReProGlo assay, and the embryonic stem cell test, and zebrafish embryotoxicity assay as 'apical' tests to correctly predict developmental toxicity for 11 out of 12 compounds, and to explain the one false negative [7]. Here we report on applying this battery within the context of grouping and read across, put forward as a potential tool to fill data gaps and avoid animal testing, to distinguish in vivo non- or weak developmental toxicants from potent developmental toxicants within groups of structural analogs. The battery correctly distinguished 2-methylhexanoic acid, monomethyl phthalate, and monobutyltin trichloride as non- or weak developmental toxicants from structurally related developmental toxicants valproic acid, mono-ethylhexyl phthalate, and tributyltin chloride, respectively, and, therefore, holds promise as a biological verification model in grouping and read across approaches. The relevance of toxicokinetic information is indicated.

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

    SciTech Connect

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

    1990-03-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    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.

  5. Passive Dosing in Chronic Toxicity Tests with the Nematode Caenorhabditis elegans.

    PubMed

    Fischer, Fabian; Böhm, Leonard; Höss, Sebastian; Möhlenkamp, Christel; Claus, Evelyn; Düring, Rolf-Alexander; Schäfer, Sabine

    2016-09-01

    In chronic toxicity tests with Caenorhabditis elegans, it is necessary to feed the nematode with bacteria, which reduces the freely dissolved concentration (Cfree) of hydrophobic organic chemicals (HOCs), leading to poorly defined exposure with conventional dosing procedures. We examined the efficacy of passive dosing of polycyclic aromatic hydrocarbons (PAHs) using silicone O-rings to control exposure during C. elegans toxicity testing and compared the results to those obtained with solvent spiking. Solid-phase microextraction and liquid-liquid extraction were used to measure Cfree and the chemicals taken up via ingestion. During toxicity testing, Cfree decreased by up to 89% after solvent spiking but remained constant with passive dosing. This led to a higher apparent toxicity on C. elegans exposed by passive dosing than by solvent spiking. With increasing bacterial cell densities, Cfree of solvent-spiked PAHs decreased while being maintained constant with passive dosing. This resulted in lower apparent toxicity under solvent spiking but an increased apparent toxicity with passive dosing, probably as a result of the higher chemical uptake rate via food (CUfood). Our results demonstrate the utility of passive dosing to control Cfree in routine chronic toxicity testing of HOCs. Moreover, both chemical uptake from water or via food ingestion can be controlled, thus enabling the discrimination of different uptake routes in chronic toxicity studies.

  6. Passive Dosing in Chronic Toxicity Tests with the Nematode Caenorhabditis elegans.

    PubMed

    Fischer, Fabian; Böhm, Leonard; Höss, Sebastian; Möhlenkamp, Christel; Claus, Evelyn; Düring, Rolf-Alexander; Schäfer, Sabine

    2016-09-01

    In chronic toxicity tests with Caenorhabditis elegans, it is necessary to feed the nematode with bacteria, which reduces the freely dissolved concentration (Cfree) of hydrophobic organic chemicals (HOCs), leading to poorly defined exposure with conventional dosing procedures. We examined the efficacy of passive dosing of polycyclic aromatic hydrocarbons (PAHs) using silicone O-rings to control exposure during C. elegans toxicity testing and compared the results to those obtained with solvent spiking. Solid-phase microextraction and liquid-liquid extraction were used to measure Cfree and the chemicals taken up via ingestion. During toxicity testing, Cfree decreased by up to 89% after solvent spiking but remained constant with passive dosing. This led to a higher apparent toxicity on C. elegans exposed by passive dosing than by solvent spiking. With increasing bacterial cell densities, Cfree of solvent-spiked PAHs decreased while being maintained constant with passive dosing. This resulted in lower apparent toxicity under solvent spiking but an increased apparent toxicity with passive dosing, probably as a result of the higher chemical uptake rate via food (CUfood). Our results demonstrate the utility of passive dosing to control Cfree in routine chronic toxicity testing of HOCs. Moreover, both chemical uptake from water or via food ingestion can be controlled, thus enabling the discrimination of different uptake routes in chronic toxicity studies. PMID:27494096

  7. Periphyton photosynthesis as an indicator of effluent toxicity: Relationship to effects on animal test species

    SciTech Connect

    Lewis, M.A.

    1992-01-01

    The use of freshwater and marine plants in effluent toxicity evaluations is uncommon despite the presence of test methods and recommendations for their use. It has been assumed that aquatic plants are less sensitive than animal test species and consequently, results from toxicity tests with invertebrates and fish have been used often as a surrogate data base. The study evaluated the ability of these animal toxicity tests to provide safe concentrations for in-stream periphyton. The toxicity of several samples of a treated municipal effluent were determined during a five-month period by monitoring short-term changes in periphyton photosynthesis (carbon-14 uptake) and by observing the effects on young production and survival of cultured daphnids and the fathead minnow. The effect levels from the various tests were compared. The effluent was seldom acutely toxic to Daphnia magna and the fathead minnow (Pimephales promelas) but it was consistently acutely and chronically toxic to Ceriodaphnia dubia. Chronic effect levels ranged between 17 and 71% effluent. Significant inhibition and stimulation of periphyton photosynthesis occurred at concentrations of 6 to 39% effluent. Periphyton photosynthesis was a more sensitive effect parameter than animal survival and in some cases than Ceriodaphnia reproductive performance. The results indicate that effluent toxicity tests conducted routinely with daphnids and fish may not be sufficient to predict effects on indigenous flora in receiving waters.

  8. Promoting the 3Rs to enhance the OECD fish toxicity testing framework.

    PubMed

    Hutchinson, Thomas H; Wheeler, James R; Gourmelon, Anne; Burden, Natalie

    2016-04-01

    Fish toxicity testing has been conducted since the 1860's in order to help define safe levels of chemical contaminants in lakes, rivers and coastal waters. The historical emphasis on acute lethality testing of chemicals has more recently focussed on long term sublethal effects of chemicals on fish and their prey species. Fish toxicity testing is now embedded in much environment legislation on chemical safety while it is recognized that animal use should be Replaced, Reduced and Refined (the 3Rs) where possible. The OECD Fish Toxicity Testing Framework provides a useful structure with which to address the needs of environmental safety assessment whilst implementing the 3Rs. This commentary aims to promote the implementation of the recommendations of the OECD Fish Toxicity Testing Framework. PMID:26873775

  9. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... adjusted to the rate desired. (ii) The test substance is introduced into each test chamber. In a flow..., photodegradation, chemical reaction, volatilization, or sorption. (iii) Measurement of test substance. (A) For... includes determining the flow rate through each chamber and the concentration of the test...

  10. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... seq.). This guideline prescribes test procedures and conditions using freshwater and marine algae to... definitions also apply to this guideline: (1) Algicidal means having the property of killing algae. (2... volumes of nutrient medium and/or test solution. Start the test by introducing algae into the test...

  11. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... seq.). This guideline prescribes test procedures and conditions using freshwater and marine algae to... definitions also apply to this guideline: (1) Algicidal means having the property of killing algae. (2... volumes of nutrient medium and/or test solution. Start the test by introducing algae into the test...

  12. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... seq.). This guideline prescribes test procedures and conditions using freshwater and marine algae to... definitions also apply to this guideline: (1) Algicidal means having the property of killing algae. (2... volumes of nutrient medium and/or test solution. Start the test by introducing algae into the test...

  13. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... seq.). This guideline prescribes test procedures and conditions using freshwater and marine algae to... definitions also apply to this guideline: (1) Algicidal means having the property of killing algae. (2... volumes of nutrient medium and/or test solution. Start the test by introducing algae into the test...

  14. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... seq.). This guideline prescribes test procedures and conditions using freshwater and marine algae to... definitions also apply to this guideline: (1) Algicidal means having the property of killing algae. (2... volumes of nutrient medium and/or test solution. Start the test by introducing algae into the test...

  15. Biological effects of high-LET particles on corn-seed embryos in the Apollo-Soyuz Test Project--Biostack III experiment.

    PubMed

    Peterson, D D; Benton, E V; Tran, M; Yang, T; Freeling, M; Craise, L; Tobias, C A

    1977-01-01

    High-LET particle hits in embryos of Zea mays corn seeds, flown as part of Biostack III in the Apollo-Soyuz Test Project, were determined via plastic nuclear track detectors. Based on etched particle-track measurements, 41 embryos were hit in seed layer 1 which contained 80 seeds, and 49 hits occurred in layer 2 which contained 79 seeds. The mean LET value and range of atomic numbers of recorded hits is, respectively, 210 +/- 57 keV micrometers -1 and 9 < or approximately Z < or approximately 26. Detailed analysis of one particular seed showing marked growth anomalies revealed two hits in the central region of the embryo. These two hits had LET values in the region of 100-150 keV micrometers-1, and Z > or approximately 20.

  16. Development of a test system for screening toxic substances: a comparison using organic substances

    SciTech Connect

    Thomas, C.L.

    1985-01-01

    The purpose of this research was to develop a test system for screening toxic substances by predicting their aquatic ecosystem effects. The system studied was a static, one liter microcosm with a diverse species assemblage. The microcosm was composed of biotic inoculum, chemically defined medium and sediment. The biotic inoculum contained primary producers, grazers, carnivores and decomposers. Three different types of sediment were studied: sand, clay, and clay plus sand. Four organic chemicals: phenol, triethylene glycol (TEG), quinoline and naphthoquinone were evaluated with this test system. The toxicities of TEG, quinoline and naphthoquinone were compared for each sediment type. Toxicity was evaluated in terms of the chemical's effects on primary productivity and heterotrophic activity though other effects are also noted. Naphthoquinone concentration exhibited no correlation between ecosystem property values and therefore, could not be ranked. Phenol exhibited the greatest toxicity to net production immediately after the toxicant addition. Quinoline was most toxic to net production over the longer time scale. TEG exhibited the least toxicity to net production, however, TEG exhibited higher toxicity to heterotrophic activity than either quinoline or phenol. Although the type of sediment used in the microcosms did not change the relative toxicities of the chemicals, the microcosms with clay sediment always were observed to exhibit lower net production and higher variability.

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

    NASA Astrophysics Data System (ADS)

    Wardini, Trimurti Hesti; Notodarmojo, Peni Astrini

    2015-09-01

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

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

    SciTech Connect

    Wardini, Trimurti Hesti; Notodarmojo, Peni Astrini

    2015-09-30

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

  19. Toxicity tests of soil contaminated by recycling of scrap plastics

    SciTech Connect

    Wong, M.H.; Chui, V.W. )

    1990-03-01

    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.

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

    PubMed

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

    The process of gasification of sewage sludge generates by-products, which may be contaminated with toxic and hazardous substances, both organic and inorganic. It is therefore important to assess the environmental risk associated with this type of waste. The feasibility of using an ecotoxicological tests for this purpose was determined in the presented study. The applied tests contained indicator organisms belonging to various biological groups (bacteria, crustaceans, plants). The subject of the study were solid (ash, char) and liquid (tar) by-products generated during gasification (in a fixed bed reactor) of dried sewage sludge from various wastewater treatment systems. The tested samples were classified based on their toxic effect. The sensitivity of the indicator organisms to the tested material was determined. In-house procedures for the preparation for toxicity analysis of both sewage sludge and by-products generated during the gasification were presented. The scope of work also included the determination of the effect of selected process parameters (temperature, amount of gasifying agent) on the toxicity of gasification by-products depending on the sewage sludge source. It was shown that both the type of sewage sludge and the parameters of the gasification process affects the toxicity of the by-products of gasification. However, the results of toxicity studies also depend on the type of ecotoxicological test used, which is associated with a different sensitivity of the indicator organisms. Nevertheless, it may be concluded that the by-products formed during the gasification of the low toxicity sewage sludge can be regarded as non-toxic or low toxic. However, the results analysis of the gasification of the toxic sludge were not conclusive, which leads to further research needs in this area. PMID:25827844

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

    PubMed

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

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

  2. 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.

  3. Toxicity testing strategies for assessing water-quality conditions in receiving streams

    SciTech Connect

    Stewart, A.J.

    1994-12-31

    This paper explores the use of short-term, EPA-approved laboratory toxicity tests for assessing water-quality conditions in streams and rivers. Strategies for the cost-effective application of such tests for long-term monitoring objectives are considered in the context of logistic constraints and statistical design. A subtle but important difference in objectives for effluent versus ambient testing is this: in effluent testing for regulatory purposes, a key objective is to determine how toxic an effluent is; in ambient testing, the main objective usually is that of determining if the water at a site is toxic. This difference shapes the strategy for cost-effective ambient testing and determines the framework for effective statistical analysis and interpretation of ambient toxicity test results. Recommendations derived as `` lessons learned`` from large-scale ambient toxicity testing programs for receiving streams at Department of Energy (DOE) facilities include: (1) testing more frequently with one species (preferably Ceriodaphnia) generally is more effective, in terms of information gained per dollar spent, than testing less frequently with two or more species; (2) use five or more sites per test period, plus two or more reference sites, whenever possible; (3) use four to six test periods per year; and (4) use diagnostic testing to supplement the ambient-testing program. Various laboratory and in situ methods for environmental assessment are now under development, but these methods probably will not gain acceptance for use in regulatory situations for many years. Rapid growth in need for ecological risk assessments outstrips the rate at which new test procedures are approved for regulatory purposes. Thus, laboratory tests for estimating possible environmental impacts of toxic or disruptive pollutants are likely to be used more frequently, not less frequently, during the next decade.

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

    SciTech Connect

    Rippon, G.D.; Riley, S.J.

    1996-12-01

    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.

  5. Evaluation of the sensitivity of freshwater organisms used in toxicity tests of wastewater from explosives company.

    PubMed

    Ribeiro, Elaine Nolasco; da Silva, Flávio Teixeira; de Paiva, Teresa Cristina Brazil

    2012-10-01

    Explosives industries are a source of toxic discharge. The aim of this study was to compare organisms sensitivity (Daphnia similis, Danio rerio, Escherichia coli and Pseudomonas putida) in detecting acute toxicity in wastewater from two explosives, 2,4,6-TNT (TNT) and nitrocellulose. The samples were collected from an explosives company in the Paraiba Valley, São Paulo, Brazil. The effluents from TNT and nitrocellulose production were very toxic for tested organisms. Statistical tests indicated that D. similis and D. rerio were the most sensitive organisms for toxicity detection in effluents from 2,4,6-TNT and nitrocellulose production. The P. putida bacteria was the organism considered the least sensitive in indicating toxicity in effluents from nitrocellulose.

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

    SciTech Connect

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

    1998-01-01

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

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

    USGS Publications Warehouse

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

    1998-01-01

    An acute (96 h) pore-water toxicity test protocol using germination and growth of Ulva fasciata zoospores as endpoints was developed to test the toxicity of marine and estuarine sediment pore-water samples. Tests with an organic toxicant (sodium dodecyl sulfate; SDS), three metals (Cd, Cu, and Zn), and ammonia (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.

  8. EPA'S TOXCAST PROGRAM FOR PREDICTING HAZARD AND PRIORITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals that likely represent the greatest hazard to human ...

  9. EPA's Toxcast ™ Program for Predicting Hazard and Priortizing Toxicity Testing of Environemntal Chemicals (T)

    EPA Science Inventory

    EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals that likely represent the greatest hazard to human ...

  10. 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.

  11. 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...