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Sample records for embryo toxicity test

  1. 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.

  2. 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

  3. Use of fish embryo toxicity tests for the prediction of acute fish toxicity to chemicals.

    PubMed

    Belanger, Scott E; Rawlings, Jane M; Carr, Gregory J

    2013-08-01

    The fish embryo test (FET) is a potential animal alternative for the acute fish toxicity (AFT) test. A comprehensive validation program assessed 20 different chemicals to understand intra- and interlaboratory variability for the FET. The FET had sufficient reproducibility across a range of potencies and modes of action. In the present study, the suitability of the FET as an alternative model is reviewed by relating FET and AFT. In total, 985 FET studies and 1531 AFT studies were summarized. The authors performed FET-AFT regressions to understand potential relationships based on physical-chemical properties, species choices, duration of exposure, chemical classes, chemical functional uses, and modes of action. The FET-AFT relationships are very robust (slopes near 1.0, intercepts near 0) across 9 orders of magnitude in potency. A recommendation for the predictive regression relationship is based on 96-h FET and AFT data: log FET median lethal concentration (LC50) = (0.989 × log fish LC50) - 0.195; n = 72 chemicals, r = 0.95, p < 0.001, LC50 in mg/L. A similar, not statistically different regression was developed for the entire data set (n = 144 chemicals, unreliable studies deleted). The FET-AFT regressions were robust for major chemical classes with suitably large data sets. Furthermore, regressions were similar to those for large groups of functional chemical categories such as pesticides, surfactants, and industrial organics. Pharmaceutical regressions (n = 8 studies only) were directionally correct. The FET-AFT relationships were not quantitatively different from acute fish-acute fish toxicity relationships with the following species: fathead minnow, rainbow trout, bluegill sunfish, Japanese medaka, and zebrafish. The FET is scientifically supportable as a rational animal alternative model for ecotoxicological testing of acute toxicity of chemicals to fish. PMID:23606235

  4. 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

  5. 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...

  6. 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...

  7. 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. PMID:26477574

  8. 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. PMID:24464135

  9. 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

  10. 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.

  11. 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

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

    EPA Science Inventory

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

  13. 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.

  14. 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. PMID:26506399

  15. 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.)

  16. 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 ...

  17. 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

  18. 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.

  19. Toxicity of chlorine to zebrafish embryos

    PubMed Central

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

    2014-01-01

    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 – 50 ppm unbuffered chlorine solution for 5 – 10 min. Treatment of embryos with chlorine has significant germicidal effects for many Gram-negative bacteria, viruses, and trophozoite stages of protozoa, it has reduced efficacy against cyst or spore stages of protozoa and certain Mycobacterium spp. Therefore, we evaluated the toxicity of unbufferred and buffered chlorine solution to embryos exposed at 6 or 24 hours post-fertilization (hpf) to determine if 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 pHs, and chlorine causes elevated pH. Consistent with this, we found that unbufferred 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 for 5 min with unbuffered chlorine solution at 100 ppm. One trial indicated that AB fish, a popular outbred line, are more susceptible to toxicity than 5Ds. This suggests that variability between zebrafish lines occurs, and researchers should evaluate each line or strain under their particular laboratory conditions for selection of the optimum chlorine treatment procedure. PMID:24429474

  20. 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

  1. Toxicity induced by emodin on zebrafish embryos.

    PubMed

    He, Qiuxia; Liu, Kechun; Wang, Sifeng; Hou, Hairong; Yuan, Yanqiang; Wang, Ximin

    2012-04-01

    Emodin, a widely available herbal remedy, has a variety of pharmacological actions and valuable clinical applications. The potential effect of emodin on zebrafish (Danio rerio) embryos was evaluated. Zebrafish embryos were incubated with 0.1-2 μg/mL of emodin from 7 hours to 6 days postfertilization (dpf). Emodin, at concentrations of 0.25 μg/mL and above, negatively affected embryo survival and hatching success. Emodin induced a large suite of abnormalities on zebrafish embryos, such as edema, crooked trunk, and abnormal morphogenesis. To elucidate the mechanism of action, the transcript levels of drug-metabolism genes (CYP3A) and a multiple drug-resistance gene (MDR1) were detected by reverse-transcript polymerase chain reaction. Embryos showed increases in mRNA accumulation of CYP3A and MDR1. The above-described results indicated that emodin impaired zebrafish embryo development and some organ morphogenesis, and CYP3A and MDR1 were involved in the process. These findings suggest that emodin was toxic to zebrafish lavae at relatively low concentrations. PMID:21834668

  2. 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. PMID:22449444

  3. 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.

  4. 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. PMID:25929752

  5. Developmental toxicity of cartap on zebrafish embryos.

    PubMed

    Zhou, Shengli; Dong, Qiaoxiang; Li, Shaonan; Guo, Jiangfeng; Wang, Xingxing; Zhu, Guonian

    2009-12-13

    Cartap is a widely used insecticide which belongs to a member of nereistoxin derivatives and acts on nicotinic acetylcholine receptor site. Its effects on aquatic species are of grave concern. To explore the potential developmental toxicity of cartap, zebrafish embryos were continually exposed, from 0.5 to 144h post-fertilization, to a range of concentrations of 25-1000microg/l. Results of the experiment indicated that cartap concentrations of 100microg/l and above negatively affected embryo survival and hatching success. Morphological analysis uncovered a large suite of abnormalities such as less melanin pigmentation, wavy notochord, crooked trunk, fuzzy somites, neurogenesis defects and vasculature defects. The most sensitive organ was proved to be the notochord which displayed defects at concentrations as low as 25microg/l. Both sensitivity towards exposure and localization of the defect were stage specific. To elucidate mechanisms concerning notochord, pigmentation, and hatching defects, enzyme assay, RT Q-PCR, and different exposure strategies were performed. For embryos with hatching failure, chorion was verified not to be digested, while removing cartap from exposure at early pre-hatching stage could significantly increase the hatching success. However, cartap was proved, via vitro assay, to have no effect on proteolytic activity of hatching enzyme. These findings implied that the secretion of hatching enzyme might be blocked. We also revealed that cartap inhibited the activity of melanogenic enzyme tyrosinase and matrix enzyme lysyl oxidase and induced expression of their genes. These suggested that cartap could impaired melanin pigmentation of zebrafish embryos through inhibiting tyrosinase activity, while inhibition of lysyl oxidase activity was responsible for notochord undulation, which subsequently caused somite defect, and at least partially responsible for defects in vasculature and neurogenesis. PMID:19923012

  6. Toxic effects of brominated indoles and phenols on zebrafish embryos.

    PubMed

    Kammann, U; Vobach, M; Wosniok, W

    2006-07-01

    Organobromine compounds in the marine environment have been the focus of growing attention in past years. In contrast to anthropogenic brominated flame retardants, other brominated compounds are produced naturally, e.g., by common polychaete worms and algae. Brominated phenols and indoles assumed to be of biogenic origin have been detected in water and sediment extracts from the German Bight. These substances as well as some of their isomers have been tested with the zebrafish embryo test and were found to cause lethal as well as nonlethal malformations. The zebrafish test was able to detect a log K(OW)-related toxicity for bromophenols, suggesting nonpolar narcosis as a major mode of action. Different effect patterns could be observed for brominated indoles and bromophenols. The comparison of effective concentrations in the zebrafish embryo test with the concentrations determined in water samples suggests the possibility that brominated indoles may affect early life stages of marine fish species in the North Sea. PMID:16418895

  7. 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.

  8. Embryo toxicity and teratogenicity of formaldehyde.

    PubMed

    Thrasher, J D; Kilburn, K H

    2001-01-01

    mitochondria, lysosomes, and the endoplasmic reticulum. The alterations in enzymatic activity persisted 4 mo following birth. In addition, formaldehyde caused metabolic acidosis, which was augmented by iron deficiency. Furthermore, newborns exposed to formaldehyde in utero had abnormal performances in open-field tests. Disparities in teratogenic effects of toxic chemicals are not unusual. For example, chlorpyrifos has not produced teratogenic effects in rats when mothers are exposed on days 6-15 (Katakura Y, et al. Br J Ind Med 1993, pp 176-82 [reference 5 herein]) of gestation (Breslin WJ, et al. Fund Appl Toxicol 1996, pp 119-30; and Hanley TR, et al. Toxicol Sci 2000, pp 100-08 [references 6 and 7, respectively, herein]). However, either changing the endpoints for measurement or exposing neonates during periods of neurogenesis (days 1-14 following birth) and during subsequent developmental periods produced adverse effects. These effects included neuroapoptosis, decreased deoxyribonucleic acid and ribonucleic acid synthesis, abnormalities in adenylyl cyclase cascade, and neurobehavioral effects (Johnson DE, et al. Brain Res Bull 1998, pp 143-47; Lassiter TL, et al. Toxicol Sci 1999, pp 92-100; Chakraborti TK, et al. Pharmacol Biochem Behav 1993, pp 219-24; Whitney KD, et al. Toxicol Appl Pharm 1995, pp 53-62; Chanda SM, et al. Pharmacol Biochem Behav 1996, pp 771-76; Dam K, et al. Devel Brain Res 1998, pp 39-45; Campbell CG, et al. Brain Res Bull 1997, pp 179-89; and Xong X, et al. Toxicol Appl Pharm 1997, pp 158-74 [references 8-15, respectively, herein]). Furthermore, the terata caused by thalidomide is a graphic human example in which the animal model and timing of exposure were key factors (Parman T, et al. Natl Med 1999, pp 582-85; and Brenner CA, et al. Mol Human Repro 1998, pp 887-92 [references 16 and 17, respectively, herein]). Thus, it appears that more sensitive endpoints (e.g., enzyme activity, generation of reactive oxygen species, timing of exposure) for the

  9. Assessing the toxicity of sediments using the medaka embryo-larval assay and 2 other bioassays.

    PubMed

    Barhoumi, Badreddine; Clérandeau, Christelle; Landi, Laure; Pichon, Anaïk; Le Bihanic, Florane; Poirier, Dominique; Anschutz, Pierre; Budzinski, Hélène; Driss, Mohamed Ridha; Cachot, Jérôme

    2016-09-01

    Sediments are sinks for aquatic pollutants, and analyzing toxicity in such complex matrices is still challenging. To evaluate the toxicity of bioavailable pollutants accumulated in sediments from the Bizerte lagoon (Tunisia), a novel assay, the medaka embryo-larval assay by sediment contact, was applied. Japanese medaka (Oryzias latipes) embryos were incubated in direct contact with sediment samples up to hatching. Lethal and sublethal adverse effects were recorded in embryos and larvae up to 20 d postfertilization. Results from medaka embryo-larval assay were compared with cytotoxicity (Microtox®), genotoxicity (SOS chromotest), and pollutant content of sediments. The results highlight differences in the contamination profile and toxicity pattern between the different studied sediments. A significant correlation was shown between medaka embryo-larval assay by sediment contact and SOS chromotest responses and concentrations of most organic pollutants studied. No correlation was shown between pollutant levels and Microtox. According to the number of sediment samples detected as toxic, medaka embryo-larval assay by sediment contact was more sensitive than Microtox, which in turn was more sensitive than the SOS chromotest; and medaka embryo-larval assay by sediment contact allowed sediment toxicity assessment of moderately polluted sediments without pollutant extraction and using an ecologically realistic exposure scenario. Although medaka embryo-larval assay by sediment contact should be tested on a larger sample set, the results show that it is sensitive and convenient enough to monitor the toxicity of natural sediments. Environ Toxicol Chem 2016;35:2270-2280. © 2016 SETAC. PMID:26823140

  10. 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

  11. 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.

  12. 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...

  13. A novel contact assay for testing aryl hydrocarbon receptor (AhR)-mediated toxicity of chemicals and whole sediments in zebrafish (Danio rerio) embryos.

    PubMed

    Schiwy, Sabrina; Bräunig, Jennifer; Alert, Henriette; Hollert, Henner; Keiter, Steffen H

    2015-11-01

    The European Water Framework Directive aims to achieve a good ecological and chemical status in surface waters until 2015. Sediment toxicology plays a major role in this intention as sediments can act as a secondary source of pollution. In order to fulfill this legal obligation, there is an urgent need to develop whole-sediment exposure protocols, since sediment contact assays represent the most realistic scenario to simulate in situ exposure conditions. Therefore, in the present study, a vertebrate sediment contact assay to determine aryl hydrocarbon receptor (AhR)-mediated activity of particle-bound pollutants was developed. Furthermore, the activity and the expression of the CYP1 family in early life stages of zebrafish after exposure to freeze-dried sediment samples were investigated. In order to validate the developed protocol, effects of β-naphthoflavone and three selected sediment on zebrafish embryos were investigated. Results documented clearly AhR-mediated toxicity after exposure to β-naphthoflavone (β-NF) and to the sediment from the Vering canal. Upregulation of mRNA levels was observed for all investigated sediment samples. The highest levels of all investigated cyp genes (cyp1a, cyp1b1, cyp1c1, and cyp1c2) were recorded after exposure to the sediment sample of the Vering canal. In conclusion, the newly developed sediment contact assay can be recommended for the investigation of dioxin-like activities of single substances and the bioavailable fraction of complex environmental samples. Moreover, the exposure of whole zebrafish embryos to native (freeze-dried) sediment samples represents a highly realistic and ecologically relevant exposure scenario. PMID:24958532

  14. 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

  15. Estradiol uptake, toxicity, metabolism, and adverse effects on cadmium-treated amphibian embryos.

    PubMed Central

    Fridman, Osvaldo; Corró, Lucrecia; Herkovits, Jorge

    2004-01-01

    The exposure of Bufo arenarum embryos to 25 micromol/L 17beta-estradiol (E2) resulted in 100% lethality within 48 hr, whereas 10 micromol//L E2 was the no observed effect concentration value for short-term chronic (7 days) exposure. The toxicity profile curves show that lethal effects were proportional to the E2 concentration and the time of exposure. The E2 uptake resulted in 20.1 ng E2/mg embryo at 8 hr posttreatment, but 67.3% of this value was achieved during the first 30 min of incubation with this estrogen. Regarding metabolism, the embryos synthesize estrone (E1) from E2 by means of 17beta-hydroxysteroid dehydrogenase. Simultaneous treatments of Bufo arenarum embryos with 1 mg/L Cd2+ and 0.1, 1, or 10 micromol/L E2 enhanced the lethality exerted by cadmium in 76.7, 80, and 83.3% of embryos, respectively. The results indicate that estrogenic endocrine disruptors could have an adverse effect on amphibian embryos and enhance the toxic effect of Cd on amphibian embryos. This study points to the possibility of using the AMPHITOX test as a screening method for potential endocrine disruption as well as the combined effects of chemical mixtures. PMID:15175173

  16. 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...

  17. 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...

  18. 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. PMID:26914601

  19. 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...

  20. 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

  1. 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

  2. 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.

  3. Use of Medaka in Toxicity Testing

    PubMed Central

    Cowden, John; Hinton, David E.; Johnson, Rodney; Flynn, Kevin; Hardman, Ronald C.; Yuen, Bonny; Law, Sheran; Kullman, Seth W.; Au, Doris W.T.

    2015-01-01

    Small aquarium fishes are increasingly used as animal models, and one of these, Japanese Medaka (Oryzias latipes), is frequently utilized for toxicity testing. While these vertebrates have many similarities with their terrestrial counterparts, there are differences that must be considered if these organisms are to be used to their highest potential. Testing commonly may employ either the developing embryo or adults; both are easy to use and to work with. We present here three main protocols to illustrate the utility and breadth of toxicity testing possible using medaka fish. The first protocol assesses neurotoxicity in developing embryos. The second protocol describes the sexual genotyping of medaka to evaluate toxicant effects on sexual phenotype after treatment with endocrine disrupting chemicals. The third protocol assesses hepatotoxicity in adult fish after treatment with a model hepatotoxicant. The methods run the gamut from immunohistology through PCR to basic histological techniques. PMID:20922755

  4. Studies of embryo toxicity in rats and rabbits.

    PubMed

    Lorke, D; Machemer, L

    1975-01-01

    Embryo toxicity studies were carried out to investigate the effects of different doses of fluorescent whitening agents (FWAs) after oral administration to pregnant rats from the 6th to the 15th day of pregnancy and to rabbits from the 6th to the 18the day of pregnancy. In own studies two FWAs of the bis(triazinylamino or triazoly)stilbenedisulfonic acid type showed no embryo-toxic or teratogenic effect on wither species at daily doses up to 1000 mg/kg. Also the toxic dose to the mothers, 3000 mg/kg, given to rabbits in case of one FWA was without these effects. In the studies of KEPLINGER, et al. (Toxicol. Appl. Parmacol. 27: 494-506, 1974) a triazolylstilbenemonosulfonic acid derivative, two bis(triazinylamino)stilbenedisulfonic acid derivatives and a bis(sulfostyryl)diphenyl derivative had no terato-enic effect on rabbits when administered orally in doses of up to 30 mg/kg/day. PMID:1064542

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. Toxicity of sediment cores from Yangtze River estuary to zebrafish (Danio rerio) embryos.

    PubMed

    Wang, Peipei; Zhang, Lili; Liu, Li; Chen, Ling; Gao, Hongwen; Wu, Lingling

    2015-11-01

    Toxicity evaluation is an important segment in sediment quality monitoring in order to protect aquatic organisms and human health. The purpose of this study is to assess the toxicity of sediments from three sediment cores in Yangtze River Estuary, China, using the zebrafish (Danio rerio) embryo tests. Fertilized zebrafish eggs were exposed to both whole sediments and sediment organic extracts prepared from collected sediments, in order to provide a comprehensive and realistic insight into the bioavailable toxicity potential of the sediments. As end points, development parameters (mortality, hatching rate, and abnormality) in the developing embryos were recorded during the 96-h exposure. The results showed that some samples increased mortality, inhibited the hatching of embryos, and induced morphological abnormalities. The embryonic toxicities presented serrated changes and irregular distribution with depth, which may be related to hydrodynamic effect and unstable environmental input. However, lethal and sub-lethal effects were more significant at the sub-surface sediments (10∼40 cm), which indicated that the pollution is more serious in recent decades. PMID:25163567

  10. The fish embryo test (FET): origin, applications, and future.

    PubMed

    Braunbeck, Thomas; Kais, Britta; Lammer, Eva; Otte, Jens; Schneider, Katharina; Stengel, Daniel; Strecker, Ruben

    2015-11-01

    Originally designed as an alternative for the acute fish toxicity test according to, e.g., OECD TG 203, the fish embryo test (FET) with the zebrafish (Danio rerio) has been optimized, standardized, and validated during an OECD validation study and adopted as OECD TG 236 as a test to assess toxicity of embryonic forms of fish. Given its excellent correlation with the acute fish toxicity test and the fact that non-feeding developmental stages of fish are not categorized as protected stages according to the new European Directive 2010/63/EU on the protection of animals used for scientific purposes, the FET is ready for use not only for range-finding but also as a true alternative for the acute fish toxicity test, as required for a multitude of national and international regulations. If-for ethical reasons-not accepted as a full alternative, the FET represents at least a refinement in the sense of the 3Rs principle. Objections to the use of the FET have mainly been based on the putative lack of biotransformation capacity and the assumption that highly lipophilic and/or high molecular weight substances might not have access to the embryo due to the protective role of the chorion. With respect to bioactivation, the only substance identified so far as not being activated in the zebrafish embryo is allyl alcohol; all other biotransformation processes that have been studied in more detail so far were found to be present, albeit, in some cases, at lower levels than in adult fish. With respect to larger molecules, the extension of the test duration to 96 h (i.e., beyond hatch) has-at least for the substances tested so far-compensated for the reduced access to the embryo; however, more research is necessary to fully explore the applicability of the FET to substances with a molecular weight >3 kDa as well as substances with a neurotoxic mode of action. An extension of the endpoints to also cover sublethal endpoints makes the FET a powerful tool for the detection of

  11. 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

  12. 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. PMID:11800547

  13. 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. PMID:22820428

  14. 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

  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. PMID:25923774

  16. Formation of copper complexes in landfill leachate and their toxicity to zebrafish embryos

    SciTech Connect

    Fraser, J.K.; Butler, C.A.; Timperley, M.H.; Evans, C.W.

    2000-05-01

    Toxic metal organic complexes have not been found in natural waters, although some organic acids form bioavailable lipophilic and metabolite-type metal complexes. Landfill leachates usually contain organic acids and in the urban environment these leachates, when mixed with storm waters containing Cu, could be a source of toxic Cu organic complexes in streams and estuaries. The authors investigated the formation of Cu complexes in the leachate from an active urban landfill and found that some of the complexes formed were toxic to zebrafish embryos. High and low nominal molecular weight (NMWT) fractions; >5,000 Da and <700 Da, of leachate both formed Cu complexes with almost identical Cu complexing characteristics but the toxicity was due solely to the low NMWT complexes formed in the <700 Da fraction. Chemical equilibrium modeling with MINTEQA2 and H and Cu complex conditional association constants and ligand concentrations obtained from pH and Cu titrations with a Cu ion-selective electrode and van den Berg-Ruzic analyses of the titration data was used to calculate the copper speciation in the embryo test solutions. This calculated speciation, which was confirmed by measurements of Cu{sup 2+} in the test solutions, enabled the toxicity due to the free Cu ion and to the Cu complexes to be distinguished.

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

    PubMed Central

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

    2014-01-01

    Although the biokinetics, metabolism, and chemical toxicity of uranium are well known, until recently little attention was paid to the potential toxic effects of uranium on reproduction and development in mammals. In recent years, it has been shown that uranium is a developmental toxicant when given orally or subcutaneously (SC) to mice. Decreased fertility, embryo/fetal toxicity including teratogenicity, and reduced growth of the offspring have been observed following uranium exposure at different gestation periods. For investigating the effects of DU on pregnant animals, three groups (control, sham and test) of NMRI mice were chosen. In test group 4 mg/Kg of DU were administered intraperitonealy at 11 day of gestation, in sham group only normal saline injected to interior peritoneum as indicated in the test group and in Control group which was considered as the comparison base line of our research, no injection was made. Caesarean sections were performed at 15 day of the gestation; and their placentas were examined externally. Base on our results DU caused significant external anomalies, and caused a significant decrease (p < 0.05) in the weight and diameter of placentas, the number of the embryos, their body weight and crown-rump length of fetuses. PMID:24734072

  18. Embryo toxic effects of depleted uranium on the morphology of the mouse fetus.

    PubMed

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

    2014-01-01

    Although the biokinetics, metabolism, and chemical toxicity of uranium are well known, until recently little attention was paid to the potential toxic effects of uranium on reproduction and development in mammals. In recent years, it has been shown that uranium is a developmental toxicant when given orally or subcutaneously (SC) to mice. Decreased fertility, embryo/fetal toxicity including teratogenicity, and reduced growth of the offspring have been observed following uranium exposure at different gestation periods. For investigating the effects of DU on pregnant animals, three groups (control, sham and test) of NMRI mice were chosen. In test group 4 mg/Kg of DU were administered intraperitonealy at 11 day of gestation, in sham group only normal saline injected to interior peritoneum as indicated in the test group and in Control group which was considered as the comparison base line of our research, no injection was made. Caesarean sections were performed at 15 day of the gestation; and their placentas were examined externally. Base on our results DU caused significant external anomalies, and caused a significant decrease (p < 0.05) in the weight and diameter of placentas, the number of the embryos, their body weight and crown-rump length of fetuses. PMID:24734072

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

    PubMed

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

    2008-01-01

    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

  20. Zebrafish Embryo Toxicity Microscale Model for Ichthyotoxicity Evaluation of Marine Natural Products.

    PubMed

    Bai, Hong; Kong, Wen-Wen; Shao, Chang-Lun; Li, Yun; Liu, Yun-Zhang; Liu, Min; Guan, Fei-Fei; Wang, Chang-Yun

    2016-04-01

    Marine organisms often protect themselves against their predators by chemical defensive strategy. The second metabolites isolated from marine organisms and their symbiotic microbes have been proven to play a vital role in marine chemical ecology, such as ichthyotoxicity, allelopathy, and antifouling. It is well known that the microscale models for marine chemoecology assessment are urgently needed for trace quantity of marine natural products. Zebrafish model has been widely used as a microscale model in the fields of environment ecological evaluation and drug safety evaluation, but seldom reported for marine chemoecology assessment. In this work, zebrafish embryo toxicity microscale model was established for ichthyotoxicity evaluation of marine natural products by using 24-well microplate based on zebrafish embryo. Ichthyotoxicity was evaluated by observation of multiple toxicological endpoints, including coagulation egg, death, abnormal heartbeat, no spontaneous movement, delayed hatch, and malformation of the different organs during zebrafish embryogenesis periods at 24, 48, and 72 h post-fertilization (hpf). 3,4-Dichloroaniline was used as the positive control for method validation. Subsequently, the established model was applied to test the ichthyotoxic activity of the compounds isolated from corals and their symbiotic microbes and to isolate the bioactive secondary metabolites from the gorgonian Subergorgia mollis under bioassay guidance. It was suggested that zebrafish embryo toxicity microscale model is suitable for bioassay-guided isolation and preliminary bioactivity screening of marine natural products. PMID:26838966

  1. 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

  2. Drosophila embryos as model to assess cellular and developmental toxicity of multi-walled carbon nanotubes (MWCNT) in living organisms.

    PubMed

    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

  3. 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.

  4. 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

  5. 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

  6. 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...

  7. FURTHER DEVELOPMENT OF RODENT WHOLE EMBRYO CULTURE: SOLVENT TOXICITY AND WATER INSOLUBLE COMPOUND DELIVERY SYSTEM

    EPA Science Inventory

    In order to study the in vitro embryotoxicity and dysmorphogenesis of water insoluble compounds, solvents or chemical delivery systems of low toxicity and teratogenicity to the developing embryo must be found. Therefore, day 10.5 rat embryos were cultured for 2 days in whole rat ...

  8. Transient Overexpression of adh8a Increases Allyl Alcohol Toxicity in Zebrafish Embryos

    PubMed Central

    Klüver, Nils; Ortmann, Julia; Paschke, Heidrun; Renner, Patrick; Ritter, Axel P.; Scholz, Stefan

    2014-01-01

    Fish embryos are widely used as an alternative model to study toxicity in vertebrates. Due to their complexity, embryos are believed to more resemble an adult organism than in vitro cellular models. However, concerns have been raised with respect to the embryo's metabolic capacity. We recently identified allyl alcohol, an industrial chemical, to be several orders of magnitude less toxic to zebrafish embryo than to adult zebrafish (embryo LC50 = 478 mg/L vs. fish LC50 = 0.28 mg/L). Reports on mammals have indicated that allyl alcohol requires activation by alcohol dehydrogenases (Adh) to form the highly reactive and toxic metabolite acrolein, which shows similar toxicity in zebrafish embryos and adults. To identify if a limited metabolic capacity of embryos indeed can explain the low allyl alcohol sensitivity of zebrafish embryos, we compared the mRNA expression levels of Adh isoenzymes (adh5, adh8a, adh8b and adhfe1) during embryo development to that in adult fish. The greatest difference between embryo and adult fish was found for adh8a and adh8b expression. Therefore, we hypothesized that these genes might be required for allyl alcohol activation. Microinjection of adh8a, but not adh8b mRNA led to a significant increase of allyl alcohol toxicity in embryos similar to levels reported for adults (LC50 = 0.42 mg/L in adh8a mRNA-injected embryos). Furthermore, GC/MS analysis of adh8a-injected embryos indicated a significant decline of internal allyl alcohol concentrations from 0.23-58 ng/embryo to levels below the limit of detection (< 4.6 µg/L). Injection of neither adh8b nor gfp mRNA had an impact on internal allyl alcohol levels supporting that the increased allyl alcohol toxicity was mediated by an increase in its metabolization. These results underline the necessity to critically consider metabolic activation in the zebrafish embryo. As demonstrated here, mRNA injection is one useful approach to study the role of candidate enzymes involved in

  9. Transient overexpression of adh8a increases allyl alcohol toxicity in zebrafish embryos.

    PubMed

    Klüver, Nils; Ortmann, Julia; Paschke, Heidrun; Renner, Patrick; Ritter, Axel P; Scholz, Stefan

    2014-01-01

    Fish embryos are widely used as an alternative model to study toxicity in vertebrates. Due to their complexity, embryos are believed to more resemble an adult organism than in vitro cellular models. However, concerns have been raised with respect to the embryo's metabolic capacity. We recently identified allyl alcohol, an industrial chemical, to be several orders of magnitude less toxic to zebrafish embryo than to adult zebrafish (embryo LC50 = 478 mg/L vs. fish LC50 = 0.28 mg/L). Reports on mammals have indicated that allyl alcohol requires activation by alcohol dehydrogenases (Adh) to form the highly reactive and toxic metabolite acrolein, which shows similar toxicity in zebrafish embryos and adults. To identify if a limited metabolic capacity of embryos indeed can explain the low allyl alcohol sensitivity of zebrafish embryos, we compared the mRNA expression levels of Adh isoenzymes (adh5, adh8a, adh8b and adhfe1) during embryo development to that in adult fish. The greatest difference between embryo and adult fish was found for adh8a and adh8b expression. Therefore, we hypothesized that these genes might be required for allyl alcohol activation. Microinjection of adh8a, but not adh8b mRNA led to a significant increase of allyl alcohol toxicity in embryos similar to levels reported for adults (LC50 = 0.42 mg/L in adh8a mRNA-injected embryos). Furthermore, GC/MS analysis of adh8a-injected embryos indicated a significant decline of internal allyl alcohol concentrations from 0.23-58 ng/embryo to levels below the limit of detection (< 4.6 µg/L). Injection of neither adh8b nor gfp mRNA had an impact on internal allyl alcohol levels supporting that the increased allyl alcohol toxicity was mediated by an increase in its metabolization. These results underline the necessity to critically consider metabolic activation in the zebrafish embryo. As demonstrated here, mRNA injection is one useful approach to study the role of candidate enzymes involved in

  10. 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. PMID:24231335

  11. 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.

  12. 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...

  13. 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

  14. Mixture toxicity of water contaminants-effect analysis using the zebrafish embryo assay (Danio rerio).

    PubMed

    Schmidt, Susanne; Busch, Wibke; Altenburger, Rolf; Küster, Eberhard

    2016-06-01

    Three water contaminants were selected to be tested in the zebrafish embryo toxicity test (DarT) in order to investigate the sensitivity of the zebrafish embryo toxicity test with respect to mixture effect detection. The concentration-response curves for the observed effects lethality and hypo-pigmentation were calculated after an exposure of the embryos for 96 h with a fungicide (carbendazim), a plasticizer or propellent precursor (2,4-DNT: 2,4- dinitrotoluene) and an aromatic compound (AαC: 2-amino-9H-pyrido[2,3-b]indol), respectively. Follow-up mixture tests were based on the calculated LC50 or EC50 of the single compounds and combined effects were predicted according to the mixture concepts of concentration addition (CA) and independent action (IA). The order of toxicity for the single substances was carbendazim (LC50 = 1.25 μM) < AαC (LC50 = 8.16 μM) < 2,4-DNT (LC50 = 177.05 μM). For AαC and 2,4 DNT hypo-pigmentation was observed in addition (AαC EC50 = 1.81 μM; 2,4-DNT EC50 = 8.81 μM). Two binary and one ternary mixture were studied on lethality and one on hypo-pigmentation: 2,4-DNT/AαC (LC50 = 119.21 μM, EC50 = 5.37 μM), carbendazim/AαC (LC50 = 4.49 μM) and AαC/Carbendazim/2,4 DNT (LC50 = 108.62 μM). Results showed that the effects were in agreement with the CA model when substances were tested in mixtures. Therefore, in a reasonable worst case scenario substance combination effects in fish embryos were at maximum only prone to overestimation when using CA as the mixture concept. PMID:27011319

  15. Rethinking guideline toxicity testing.

    PubMed

    Saghir, Shakil Ahmed

    2015-07-01

    The guidelines for risk assessment of plant protection products (PPPs) and other non-pharmaceuticals were developed over three decades ago and have generally not been updated to incorporate advancements in toxicology and exposure sciences. These guidelines recommend using maximum-tolerated-dose (MTD) even when human relevance of such high doses is mostly limited due to orders of magnitude margin-of-exposure. Conducting animal studies at such high doses often requires further mode-of-action (MoA) studies elucidating human relevance. In order to improve data, ILSI/HESI-ACSA technical committee proposed a tiered approach with emphasis on determining systemic dose of parent and/or metabolite(s) in test animals as biological effects are reflective of systemic rather than administered dose. Any deviation from linearity in systemic dose (saturation of absorption or elimination) in animal studies may have profound toxic effect(s) not expected to occur in likely human exposure scenarios and should be avoided. Toxicity studies should ideally be conducted at kinetically linear doses or slightly above the point of departure from linearity or kinetically-derived maximum dose (KMD) as the systemic dose nonlinearity is a more sensitive parameter occurring much earlier than the MTD endpoints. Therefore, determining systemic dose, especially KMD, in study animals is an improvement to hazard assessment of PPPs and other non-pharmaceuticals allowing toxicologists to better understand findings in animals at systemically linear as well as nonlinear doses to likely human exposures which can easily be accomplished using core study animals as outlined below. Determining systemic dose in studies will also increase the understanding of initial potential MoA of a PPPs and other non-pharmaceuticals and reduce the use of animals by avoiding unnecessary additional MoA studies. PMID:25980640

  16. 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.

  17. 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.

  18. Bivalve embryo bioassay to assess the potential toxicity of dredged material before dumping

    SciTech Connect

    Quiniou, F.

    1995-12-31

    Dredged harbor sediments frequently contain a wide spectrum of contaminants in addition to a significant percentage of organic matter. Also, dredging and dumping activities into sea water, of these highly contaminated soil may induce a harmful effect on the environment. In France, in accordance with Oslo convention guidelines, a working group on dredging activities and environment (GEODE) created since 1991 decided to set up a pilot research program to assess the intrinsic toxicity of four harbor sludges. Intrinsic toxicity of harbor muds were tested by solid phase (whole sediment) and aqueous extract bioassays (sea water elutriates) using the sublethal toxicity test bivalve embryo bioassay (Crassostrea gigas). Elutriates enable them to detect the toxicity of contaminants which may be released in the soluble form into the water column during dredging operations. While, whole sediment integrate the synergistic effects of all the contaminants (hydrophilic and hydrophobic) including pore water. Bioassays results, correlated to chemical analysis, are compared to contaminant levels determined by French working group GEODE and Canadian sediment quality criteria.

  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. 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.

  2. 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...

  3. 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

  4. Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin.

    PubMed

    Xu, Chao; Tu, Wenqing; Lou, Chun; Hong, Yingying; Zhao, Meirong

    2010-01-01

    Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers. In this study, enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC, and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays. The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm. Better separation could be achieved at lower temperature (e.g., 20 degrees C) and with lower levels of polar modifiers. Pure enantiomers were obtained on Chiralcel OD. The CD spectra of enantiomers were recorded. By comparing the elution order with a previous similar study, the absolute configuration of beta-CP enantiomers was determined. The individual enantiomers were used in zebrafish embryo test, and the results showed that beta-CP enantioselectively induced yolk sac edema, pericardial edema and crooked body. The IR-cis-alphaS and 1R-trans-alphaS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L, while the 1S-cis-alphaR and 1S-trans-alphaR induced no malformations at higher concentration (e.g., 0.3 mg/L). The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects. PMID:20608511

  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. 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

  7. Nanodiamond for biolabelling and toxicity evaluation in the zebrafish embryo in vivo.

    PubMed

    Lin, Y-C; Wu, K-T; Lin, Z-R; Perevedentseva, E; Karmenyan, A; Lin, M-D; Cheng, C-L

    2016-08-01

    Nanodiamond (ND) has been proposed for various biomedical applications, including bioimaging, biosensing and drug delivery, owing to its physical-chemical properties and biocompatibility. Particularly, ND has been demonstrated as fluorescence- and Raman-detectable labels in many cellular models. Different surface functionalization methods have been developed, varying the ND's surface properties and rendering the possibility to attach biomolecules to provide interaction with biological targets. For this, toxicity is of major concern in animal models. Aside from cellular models, a cost-effective animal test will greatly facilitate the development of applications. In this study, we use the rapid, sensitive and reproducible zebrafish embryo model for in vivo nanotoxicity test. We optimize the conditions for using this animal model and analyze the zebrafish embryonic development in the presence of ND. ND is observed in the embryo in vivo using laser confocal fluorescence microscopy and fluorescence lifetime imaging. Using the zebrafish model for a safety evaluation of ND-based nanolabel is discussed. PMID:27093912

  8. USING THE MEDAKA EMBRYO ASSAY TO INVESTIGATE DEVELOPMENTAL ETHANOL TOXICITY.

    EPA Science Inventory

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

  9. 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...

  10. New directions in toxicity testing.

    PubMed

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

    2011-01-01

    In 2007, the U.S. National Research Council (NRC) published a groundbreaking report entitled Toxicity Testing in the 21st Century: A Vision and a Strategy. The purpose of this report was to develop a long-range strategic plan to update and advance the way environmental agents are tested for toxicity. The vision focused on the identification of critical perturbations of toxicity pathways that lead to adverse human health outcomes using modern scientific tools and technologies. This review describes how emerging scientific methods will move the NRC vision forward and improve the manner in which the potential health risks associated with exposure to environmental agents are assessed. The new paradigm for toxicity testing is compatible with the widely used four-stage risk assessment framework originally proposed by the NRC in 1983 in the so-called Red Book. The Nrf2 antioxidant pathway provides a detailed example of how relevant pathway perturbations will be identified within the context of the new NRC vision for the future of toxicity testing. The implications of the NRC vision for toxicity testing for regulatory risk assessment are also discussed. PMID:21219154

  11. 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.

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

    EPA Science Inventory

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

  13. [Toxic effects of CdSe/ZnS QDs to zebrafish embryos].

    PubMed

    Chen, Mu-Fei; Huang, Cheng-Zhi; Pu, De-Yong; Zheng, Chao-Yi; Yuan, Kai-Mi; Jin, Xing-Xing; Zhang, Yao-Guang; Jin, Li

    2015-02-01

    The toxic effects of CdSe/ZnS QDs on zebrafish (Danio rerio) embryos at different developmental stages were investigated in this study. The voluntary movement frequency, body length, hatching rate, mortality and malformation rate, SOD activities, MDA contents, mRNA expression of metallothionein (MT) and heat stress protein 70 (Hsp70) were used as indicators. The results showed that the EC50 was 316.994 nmol x L(-1) for zebrafish embryos (72 hpf) when exposed to CdSe/ZnS QDs. After the CdSe/ZnS QDs exposure, the embryos showed a significant increase in mortality and malformation rate, a decrease in hatching rate and body length, an advance in hatching time, and a changing in the spontaneous movement frequency, and many other toxic effects, such as the condensation of embryonic eggs, the formation of pericardial cysts and curvature of the spine. Moreover, it was found that the MDA contents in the embryos in CdSe/ZnS QDs groups were significantly increased, and the SOD activities were changed. In addition, the mRNA expression level of MT and Hsp70 were up-regulated. All the information suggests that exposure of CdSe/ZnS QDs can cause toxic effects on zebrafish embryos, and the effects may be related to the releasing of Cd2+, particle size and oxidative stress. PMID:26031104

  14. 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. PMID:23747464

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

    PubMed

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

    2013-10-01

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

  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. Cadmium: toxic effects on the reproductive system and the embryo.

    PubMed

    Thompson, Jennifer; Bannigan, John

    2008-04-01

    The heavy metal cadmium (Cd) is a pollutant associated with several modern industrial processes. Cd is absorbed in significant quantities from cigarette smoke, and is known to have numerous undesirable effects on health in both experimental animals and humans, targeting the kidneys, liver and vascular systems in particular. However, a wide spectrum of deleterious effects on the reproductive tissues and the developing embryo has also been described. In the testis, changes due to disruption of the blood-testis barrier and oxidative stress have been noted, with onset of widespread necrosis at higher dosage exposures. Incorporation of Cd into the chromatin of the developing gamete has also been demonstrated. Ovarian Cd concentration increases with age, and has been associated with failure of progression of oocyte development from primary to secondary stage, and failure to ovulate. A further mechanism by which ovulation could be rendered ineffective is by failure of pick-up of the oocyte by the tubal cilia due to suboptimal expansion of the oocyte-cumulus complex and mis-expression of cell adhesion molecules. Retardation of trophoblastic outgrowth and development, placental necrosis and suppression of steroid biosynthesis, and altered handling of nutrient metals by the placenta all contribute to implantation delay and possible early pregnancy loss. Cd has been shown to accumulate in embryos from the four-cell stage onwards, and higher dosage exposure inhibits progression to the blastocyst stage, and can cause degeneration and decompaction in blastocysts following formation, with apoptosis and breakdown in cell adhesion. Following implantation, exposure of experimental animals to oral or parenteral Cd causes a wide range of abnormalities in the embryo, depending on the stage of exposure and dose given. Craniofacial, neurological, cardiovascular, gastrointestinal, genitourinary, and limb anomalies have all been described in placentates, with axial abnormalities and

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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. PMID:25728358

  4. 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.

  5. 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...

  6. 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

  7. Developmental toxicity testing of vaccines.

    PubMed

    Barrow, Paul C; Allais, Linda

    2013-01-01

    Preventative and therapeutic vaccines are increasingly used during pregnancy and present special considerations for developmental toxicity testing. The various components of the vaccine formulation (i.e., protein or polysaccharide antigen, adjuvants, and excipients) need to be assessed for direct effects on the developing conceptus. In addition, possible adverse influences of the induced antibodies on fetal and/or postnatal development need to be evaluated. A guidance document on the preclinical testing of preventative and therapeutic vaccines for developmental toxicity was issued by the FDA in 2006. Preclinical studies are designed to assess possible influences of vaccines on pre- and postnatal development. The choice of model animal for these experiments is influenced by species differences in the timing and extent of the transfer of the induced maternal antibodies to the fetus. The cross-placental transport of maternal immunoglobulins generally only occurs in late gestation and tends to be greater in humans and monkeys than in non-primate species. For many vaccines, the rabbit shows a greater rate of prenatal transfer of the induced antibodies than rodents. For biotechnology-derived vaccines that are not immunogenic in lower species, nonhuman primates may be the only appropriate models. It may be advisable to test new adjuvants using the ICH study designs for conventional pharmaceuticals in addition to the developmental toxicity study with the final vaccine formulation. PMID:23138897

  8. 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. PMID:26619782

  9. Exploring the zebrafish embryo as an alternative model for the evaluation of liver toxicity by histopathology and expression profiling.

    PubMed

    Driessen, Marja; Kienhuis, Anne S; Pennings, Jeroen L A; Pronk, Tessa E; van de Brandhof, Evert-Jan; Roodbergen, Marianne; Spaink, Herman P; van de Water, Bob; van der Ven, Leo T M

    2013-05-01

    The whole zebrafish embryo model (ZFE) has proven its applicability in developmental toxicity testing. Since functional hepatocytes are already present from 36 h post fertilization onwards, whole ZFE have been proposed as an attractive alternative to mammalian in vivo models in hepatotoxicity testing. The goal of the present study is to further underpin the applicability of whole ZFE for hepatotoxicity testing by combining histopathology and next-generation sequencing-based gene expression profiling. To this aim, whole ZFE and adult zebrafish were exposed to a set of hepatotoxic reference compounds. Histopathology revealed compound and life-stage-specific effects indicative of toxic injury in livers of whole ZFE and adult zebrafish. Next-generation sequencing (NGS) was used to compare transcript profiles in pooled individual RNA samples of whole ZFE and livers of adult zebrafish. This revealed that hepatotoxicity-associated expression can be detected beyond the overall transcription noise in the whole embryo. In situ hybridization verified liver specificity of selected highly expressed markers in whole ZFE. Finally, cyclosporine A (CsA) was used as an illustrative case to support applicability of ZFE in hepatotoxicity testing by comparing CsA-induced gene expression between ZFE, in vivo mouse liver and HepaRG cells on the levels of single genes, pathways and transcription factors. While there was no clear overlap on single gene level between the whole ZFE and in vivo mouse liver, strong similarities were observed between whole ZFE and in vivo mouse liver in regulated pathways related to hepatotoxicity, as well as in relevant overrepresented transcription factors. In conclusion, both the use of NGS of pooled RNA extracts analysis combined with histopathology and traditional microarray in single case showed the potential to detect liver-related genes and processes within the transcriptome of a whole zebrafish embryo. This supports the applicability of the whole ZFE

  10. 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

  11. Toxic effects of perfluorononanoic acid on the development of Zebrafish (Danio rerio) embryos.

    PubMed

    Liu, Hui; Sheng, Nan; Zhang, Wei; Dai, Jiayin

    2015-06-01

    Perfluorononanoic acid (PFNA) is a nine-carbon perfluoroalkyl acid widely used in industrial and domestic products. It is a persistent organic pollutant found in the environment as well as in the tissues of humans and wildlife. There is a concern that this chemical might be a developmental toxicant and teratogen in various ecosystems. In the present study, the toxic effects of PFNA were evaluated in zebrafish (Danio rerio) embryos. One hour post-fertilization embryos were treated with 0, 25, 50, 100, 200, 300, 350, and 400 μmol/L PFNA for 96 hr in 6-well plates. Developmental phenotypes and hatching rates were observed and recorded. Nineteen genes related to oxidative stress and lipid metabolism were examined using Quantitative RT-PCR and confirmed by whole mount in situ hybridization (WISH). Results showed that PFNA delayed the development of zebrafish embryos, reduced the hatching rate, and caused ventricular edema and malformation of the spine. In addition, the amount of reactive oxygen species in the embryo bodies increased significantly after exposure to PFNA compared with that of the control group. The Quantitative RT-PCR and WISH experiments demonstrated that mRNA expression of the lfabp and ucp2 genes increased significantly while that of sod1 and mt-nd1 decreased significantly after PFNA exposure. The mRNA expression levels of gpx1 and mt-atp6 decreased significantly in the high concentration group. However, the mRNA expression levels of both ppara and pparg did not show any significant variation after exposure. These findings suggest that PFNA affected the development of zebrafish embryos at relatively low concentrations. PMID:26040728

  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. PMID:22233769

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

    SciTech Connect

    Palmer, F.B.; Evans, C.W.; Butler, C.A.; Timperley, M.H.

    1998-08-01

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

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

    PubMed

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

    2010-09-01

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

  15. 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.

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

    PubMed

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

    2008-11-01

    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. PMID:18704254

  17. 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. PMID:22052622

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

    PubMed

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

    2013-02-01

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

  19. Nanosilver-coated socks and their toxicity to zebrafish (Danio rerio) embryos.

    PubMed

    Gao, Jiejun; Sepúlveda, Maria S; Klinkhamer, Christopher; Wei, Alexander; Gao, Yu; Mahapatra, Cecon T

    2015-01-01

    Silver nanoparticles (AgNPs) are being incorporated and are known to be released from various consumer products such as textiles. However, no data are available on the toxicity of AgNPs released from any of these commercial products. In this study, we quantified total silver released from socks into wash water by inductively coupled plasma mass spectrometry (ICP-MS) and determined the presence of AgNPs using transmission electron microscopy (TEM). We then exposed zebrafish (Danio rerio) embryos for 72 h to either this leachate ("sock-AgNP") or to the centrifugate ("spun-AgNP") free of AgNPs and compared their toxicity to that of ionic silver (Ag(+)). Our data suggest that AgNPs do get released into the wash water, and centrifugation eliminated AgNPs but did not decrease total silver concentrations, indicating that most of the silver in the sock-AgNP solution was in the ionic form. All embryos died during the first 24 h when exposed to undiluted sock-AgNP and spun-AgNP solutions resulting in significantly lower LC50 values (0.14 and 0.26 mg L(-1)) compared to AgNO3 (0.80 mg L(-1)). Similarly, at 72 hpf, both sock-derived solutions were more potent at affecting hatching and inducing abnormal development. These results suggest that both sock-AgNP and spun-AgNP solutions were more toxic than AgNO3. Previous studies have consistently shown the opposite, i.e., AgNPs are about 10 times less toxic that Ag(+). All together our results show that the high toxicity induced by the leachate of these socks is likely not caused by AgNPs or Ag(+). More studies are needed to evaluate the toxicity of the myriad of AgNP-coated commercial products that are now estimated to be close to 500. PMID:25303653

  20. Evaluation of potential embryo toxicity of albendazole sulphoxide in CF1 mice.

    PubMed

    Teruel, Miriam; Dercole, Jaqueline; Catalano, Rodolfo

    2011-04-01

    Benzimidazole compounds are used in both humans and animals for controlling helminth parasites. Albendazole has teratogenic effects attributed to its active metabolite albendazole sulphoxide. The aim of this work was to evaluate the effect of the latter compound when administered to pregnant CF1 mice during the preimplantation period. Females were superovulated by intraperitoneal injection of 10 IU of eCG and 10 IU of hCG (48h later) and were paired with males of proven fertility. Albendazole sulphoxide (200 mg/kg) was orally administered by gavages at day 1, 2 or 3 of pregnancy; the control group received only the vehicle (carboxymethylcellulose). Females were killed by cervical dislocation at day 4 of pregnancy and embryos were flushed from uteri with Ham F10 media supplemented with bovine serum albumin (0.4%). Number of collected embryos per female, percentage of morphologically normal embryos, differentiation rate and number of cells per embryos were recorded. The variables were analyzed on a per litter basis by Kruskal-Wallis test. There was no effect of albendazole sulphoxide on parameters evaluated (P>0.05). We conclude that the preimplantation mouse embryo development was not significantly affected by albendazole sulphoxide. PMID:21667669

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

    PubMed

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

    2016-08-01

    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

  2. Random Walk of Single Gold Nanoparticles in Zebrafish Embryos Leading to Stochastic Toxic Effects on Embryonic Developments

    PubMed Central

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

    2010-01-01

    We have synthesized and characterized stable (non-aggregation, non-photobleaching and non-blinking), nearly monodisperse and highly-purified Au nanoparticles, and used them to probe transport of cleavage-stage zebrafish embryos and to study their effects on embryonic development in real time. We found that single Au nanoparticles (11.6 ± 0.9 nm in diameter) passively diffused into chorionic space of the embryos via their chorionic-pore-canals and continued their random-walk through chorionic space and into inner mass of embryos. Diffusion coefficients of single nanoparticles vary dramatically (2.8×10-11 to 1.3×10-8 cm2/s) as nanoparticles diffuse through various parts of embryos, suggesting highly diverse transport barriers and viscosity gradients of embryos. The amount of Au nanoparticles accumulated in embryos increase with its concentration. Interestingly, their effects on embryonic development are not proportionally related to the concentration. Majority of embryos (74% on average) incubated chronically with 0.025-1.2 nM Au nanoparticles for 120 h developed to normal zebrafish, with some (24%) being dead and few (2%) deformed. We developed a new approach to image and characterize individual Au nanoparticles embedded in tissues using histology sample preparation methods and LSRP spectra of single nanoparticles. We found that Au nanoparticles in various parts of normally developed and deformed zebrafish, suggesting that random-walk of nanoparticles in embryos during their development might have led to stochastic effects on embryonic development. These results show that Au nanoparticles are much more biocompatible (less toxic) to the embryos than Ag nanoparticles that we reported previously, suggesting that they are better suited as biocompatible probes for imaging embryos in vivo. The results provide powerful evidences that biocompatibility and toxicity of nanoparticles highly depend on their chemical properties, and the embryos can serve as effective in

  3. 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...

  4. 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. PMID:27074386

  5. Low-dose agrochemicals and lawn-care pesticides induce developmental toxicity in murine preimplantation embryos.

    PubMed Central

    Greenlee, Anne R; Ellis, Tammy M; Berg, Richard L

    2004-01-01

    Occupational exposures to pesticides may increase parental risk of infertility and adverse pregnancy outcomes such as spontaneous abortion, preterm delivery, and congenital anomalies. Less is known about residential use of pesticides and the risks they pose to reproduction and development. In the present study we evaluate environmentally relevant, low-dose exposures to agrochemicals and lawn-care pesticides for their direct effects on mouse preimplantation embryo development, a period corresponding to the first 5-7 days after human conception. Agents tested were those commonly used in the upper midwestern United States, including six herbicides [atrazine, dicamba, metolachlor, 2,4-dichlorophenoxyacetic acid (2,4-D)], pendimethalin, and mecoprop), three insecticides (chlorpyrifos, terbufos, and permethrin), two fungicides (chlorothalonil and mancozeb), a desiccant (diquat), and a fertilizer (ammonium nitrate). Groups of 20-25 embryos were incubated 96 hr in vitro with either individual chemicals or mixtures of chemicals simulating exposures encountered by handling pesticides, inhaling drift, or ingesting contaminated groundwater. Incubating embryos with individual pesticides increased the percentage of apoptosis (cell death) for 11 of 13 chemicals (p embryo for 3 of 13 agents (p embryos (p embryo (p

  6. 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

  7. 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

  8. Evaluation of the rat embryo culture system as a predictive test for human teratogens.

    PubMed

    Guest, I; Buttar, H S; Smith, S; Varma, D R

    1994-01-01

    Ingestion of the anticonvulsant drug valproic acid and of the angiotensin converting enzyme inhibitor captopril during pregnancy has been associated with abnormal fetal outcome in humans. In contrast, the use of the antiinflammatory drug ibuprofen and the antihistamine diphenhydramine has not been documented to be embryotoxic in humans. We evaluated the rat embryo culture system as a predictive model of teratogenesis, using these four drugs as test agents. Valproic acid, ibuprofen, and diphenhydramine were embryotoxic, inducing concentration-dependent decreases in growth and a significant increase in anomalies. Valproic acid caused an increase in neural tube defects, ibuprofen increased the incidence of abnormal maxillary processes, and diphenhydramine increased the number of embryos with distorted body morphology. These abnormalities were induced at concentrations of valproic acid and diphenhydramine that are used clinically, but ibuprofen only induced toxicity at concentrations greatly exceeding the therapeutic range. Captopril was not embryotoxic up to 5 mM, the highest concentration tested. These results suggest that the rat embryo culture system produces both false positive and false negative data on the teratogenic potential of drugs. Although such an in vitro assay may be suitable to determine the mechanism of teratogenesis, it is not a sensitive indicator of potential human teratogens on its own. These data support the view that in vitro systems can only supplement clinical and epidemiological observations in humans, possibly as a method to determine mechanisms of actions of teratogens. PMID:8012899

  9. Evaluation of the detoxication efficiencies for acrylonitrile wastewater treated by a combined anaerobic oxic-aerobic biological fluidized tank (A/O-ABFT) process: Acute toxicity and zebrafish embryo toxicity.

    PubMed

    Na, Chunhong; Zhang, Ying; Deng, Minjie; Quan, Xie; Chen, Shuo; Zhang, Yaobin

    2016-07-01

    Acrylonitrile (ACN) wastewater generated during ACN production has been reported to be toxic to many aquatic organisms. However, few studies have evaluated toxicity removal of ACN wastewater during and after the treatment process. In this study, the detoxication ability of an ACN wastewater treatment plant (WWTP) was evaluated using Daphnia magna, Danio rerio and zebrafish embryo. This ACN WWTP has a combined anaerobic oxic-aerobic biological fluidized tank (A/O-ABFT) process upgraded from the traditional anaerobic oxic (A/O) process. Moreover, the potential toxicants of the ACN wastewaters were identified by gas chromatography-mass spectrometry (GC-MS). The raw ACN wastewater showed high acute and embryo toxicity. 3-Cyanopyridine, succinonitrile and a series of nitriles were detected as the toxic contributors of ACN wastewater. The A/O process was effective for the acute and embryo toxicity removal, as well as the organic toxicants. However, the A/O effluent still showed acute and embryo toxicity which was attributed by the undegraded and the newly generated toxicants during the A/O process. The residual acute and embryo toxicity as well as the organic toxicants in the A/O effluent were further reduced after going through the downstream ABFT process system. The final effluent displayed no significant acute and embryo toxicity, and less organic toxicants were detected in the final effluent. The upgrade of this ACN WWTP results in the improved removal efficiencies for acute and embryo toxicity, as well as the organic toxicants. PMID:27037768

  10. Living organisms influence on environmental conditions: pH modulation by amphibian embryos versus aluminum toxicity.

    PubMed

    Herkovits, Jorge; Castañaga, Luis Alberto; D'Eramo, José Luis; Jourani, Victoria Platonova

    2015-11-01

    The LC10, 50 and 90/24h of aluminum for Rhinella arenarum embryos at complete operculum stage were 0.55, 0.75 and 1mgAl(3+)/L respectively. Those values did not change significantly by expanding the exposure period till 168h. The aluminum toxicity was evaluated in different pH conditions by means of a citrate buffer resulting for instance, 1mgAl(3+)/L at pH 4, 4.1, 5 and 6 in 100%, 70%, 35% and 0% of lethality respectively. As an outstanding feature, the embryos changed the pH of the maintaining media both in the case of Al(3+) or citrate buffer treatments toward neutral. 10 embryos in 40mL of AMPHITOX solution were able to increase the pH from 4.2 to 7.05, a fact related with a metabolic shift resulting in an increase in nitrogen loss as ammonia. Our study point out the natural selection of the most resistant amphibian embryos both for pH or aluminum as well as the capacity of living organisms (as a population) to alter their chemical environment toward optimal conditions for their survival. As these facts occur at early life stages, it expand the concept that living organisms at ontogenic stages are biomarker of environmental signatures of the evolutionary process (Herkovits, 2006) to a global Onto-Evo concept which imply also the feedback mechanisms from living organisms to shape environmental conditions in a way that benefits them. PMID:26126231

  11. 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.

  12. 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

  13. Diepoxybutane and mitomycin C toxicity is associated with the induction of oxidative DNA damage in sea urchin embryos.

    PubMed

    Pagano, G; Degan, P; De Biase, A; Iaccarino, M; Warnau, M

    2001-12-01

    Diepoxybutane (DEB)- and mitomycin C (MMC)-associated toxicity was investigated in embryos from the sea urchin (SU) species Sphaerechinus granularis. DEB- and MMC-induced toxicity resulted in S. granularis embryos and larvae at concentrations ranging 10(-5) to 10(-4) M DEB, and 3 x 10(-6) to 3 x 10(-5) M MMC, in terms of larval malformations, developmental arrest and mortality. The formation of DNA oxidative damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured in DEB- and in MMC-exposed embryos (at gastrula stage). A dose-dependent increase in 8-OHdG levels was observed that was significantly correlated with DEB- and MMC-induced developmental defects. The results lend further support to the body of evidence associating both DEB and MMC toxicity with oxidative stress, including DNA oxidative damage. PMID:11936580

  14. 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.

  15. 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...

  16. 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...

  17. 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

  18. Spiking sediment with organochlorines for toxicity testing

    SciTech Connect

    Murdoch, M.H.; Chapman, P.M.; Norman, D.M.; Quintino, V.M.

    1997-07-01

    Sediment toxicity testing integrates responses to sediment variables and hence does not directly indicate cause and effect. One tool for determining cause and effect is sediment spiking, in which relatively uncontaminated sediment is amended with known amounts of contaminants, then tested for toxicity. However, sediment spiking methods vary considerably. The present study details appropriate methodologies (dry and wet spiking) for amending sediments with a range of organic contaminant concentrations, i.e., polychlorinated biphenyl (PCB). Target and actual concentrations were similar. A dose-response was determined, but PCB was not toxic in an acute sediment toxicity test. Chronic testing of these same sediments is reported in a companion article in this issue.

  19. 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.

  20. Differential toxicity and uptake of Diazinon on embryo-larval development of Rhinella arenarum.

    PubMed

    Aronzon, Carolina Mariel; Marino, Damián J G; Ronco, Alicia E; Pérez Coll, Cristina Silvia

    2014-04-01

    Diazinon, an anti-cholinesterase organophosphate, is an extensively used pesticide. The main objective of this work was to assess the lethal and sublethal effects of Diazinon and its comparison with the uptake by embryos and larvae of the common South American toad Rhinella arenarum by means of standardized bioassays during acute (96 h), short-term chronic (168 h) and chronic (504 h) exposures. Toxicity resulted time- and stage-dependent, thus the lethal concentration 50 for 96 h, 168 h and 504 h were 27.2; 20.1 and 6.8 mg Diazinon L(-1) for embryos and 8, 6.7 and 1.9 mg Diazinon L(-1) for larvae. It is noteworthy the remarkable differences found in the concentration which caused lethality with those causing adverse effects on development such as malformations (teratogenic effects). Therefore, the teratogenic index from 144 h was greater than two; the main adverse effects were axial flexures, irregular borders, wavy tail, microcephaly, malformed mouth and adhesive structures, gut miscoiling, underdeveloped gills, cloacal edema, desquamation and severe hydropsy. Moreover, the characteristic sublethal effect of Diazinon on larvae was abnormal behavior related to neurotoxicity with a NOEC-168 h of 4.5 mg Diazinon L(-1). Diazinon contents in R. arenarum were time-dependent and significantly related to exposure concentration for both embryos and larvae. Diazinon contents were also stage-dependent, as it was up to 27 times higher for organisms exposed from blastula stage onwards than early larvae. These facts and the Hazard Quotients, a numerical expression of ecological risk, of 2.73, which is above USEPA's Level of Concern, showed the threat that Diazinon represents for R. arenarum populations. PMID:24485812

  1. 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. PMID:24375551

  2. 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

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

    EPA Science Inventory

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

  4. 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.

  5. Total synthesis of Herbarin A and B, determination of their antioxidant properties and toxicity in zebrafish embryo model.

    PubMed

    Heimberger, Julia; Cade, Hannah C; Padgett, Jihan; Sittaramane, Vinoth; Shaikh, Abid

    2015-03-15

    Herbarin A and B were isolated from the fungal strains of Cladosporium herbarum found in marine sponges Aplysina aerophoba and Callyspongia aerizusa. Total synthesis of Herbarin A and B was achieved by carrying out a multi-step synthesis approach, and the antioxidant properties were evaluated using FRAP assay. Toxicity of these compounds was determined using a zebrafish embryo model. PMID:25690788

  6. Sulfide tolerance of four marine bioassay test species used to evaluate sediment toxicity

    SciTech Connect

    Knezovich, J.P.; Jelinski, J.A.; Anderson, S.L.; Steichen, D.J.

    1994-12-31

    Hydrogen sulfide is a potential positive interference associated with marine sediment toxicity tests. It is necessary, therefore, to evaluate the possible contribution of sulfides to sediment toxicity before toxicity attributed to anthropogenic contaminants can be determined. The sulfide tolerances of several marine bioassay test species (R. abronius, E. estuaris, M. edulis and S. purpuratus) commonly used in bulk sediment and porewater toxicity tests have not been reported. The authors used a flow-through exposure system to expose these organisms to constant concentrations of sulfide during 48-h exposure periods. Significant abnormalities occurred at 3 to 5 micromoles total sulfide per liter ({mu}M/L) in M. edulis embryos, and at 6{mu}M/L in S. purpuratus embryos. Survivorship of amphipods was significantly reduced at total sulfide concentrations of 45 and 126 {mu}M/L for R. abronius and E estuaris, respectively. These tolerances provide guidelines for evaluating the potential for sulfide toxicity prior to the initiation of toxicity tests. Because sulfide concentrations in bulk sediment and pore-water may exceed these values, care must be taken to ensure that sulfide toxicity is not contributing to toxicity observed when using these test organisms.

  7. 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

  8. 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

  9. 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

  10. 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...

  11. 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. PMID:2190824

  12. 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.

  13. Automated Zebrafish Chorion Removal and Single Embryo Placement: Optimizing Throughput of Zebrafish Developmental Toxicity Screens

    PubMed Central

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

    2012-01-01

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

  14. 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.

  15. 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.

  16. 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. PMID:25183031

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

    PubMed Central

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

    2014-01-01

    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. PMID:25183031

  18. 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...

  19. 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

  20. 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

  1. 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.

  2. 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

  3. DarT: The embryo test with the Zebrafish Danio rerio--a general model in ecotoxicology and toxicology.

    PubMed

    Nagel, Roland

    2002-01-01

    The acute fish test is an animal test whose ecotoxicological relevance is worthy of discussion. The primary aim of protection in ecotoxicology is the population and not the individual. Furthermore the concentration of pollutants in the environment is normally not in the lethal range. Therefore the acute fish test covers solely the situation after chemical spills. Nevertheless, acute fish toxicity data still belong to the base set used for the assessment of chemicals. The embryo test with the zebrafish Danio rerio (DarT) is recommended as a substitute for the acute fish test. For validation an international laboratory comparison test was carried out. A summary of the results is presented in this paper. Based on the promising results of testing chemicals and waste water the test design was validated by the DIN-working group "7.6 Fischei-Test". A normed test guideline for testing waste water with fish is available. The test duration is short (48 h) and within the test different toxicological endpoints can be examined. Endpoints from the embryo test are suitable for QSAR-studies. Besides the use in ecotoxicology the introduction as a toxicological model was investigated. Disturbance of pigmentation and effects on the frequency of heart-beat were examined. A further important application is testing of teratogenic chemicals. Based on the results DarT could be a screening test within preclinical studies. PMID:12096329

  4. 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. PMID:25259848

  5. MINIATURIZED SEDIMENT PROCEDURES FOR ASESSING TOXICITY USING MARINE AND FRESHWATER AMPHIPODS AND EMBRYO/LARVAL FISH

    EPA Science Inventory

    Sediment toxicity tests are needed that can be conducted with less sediment volume and fewer organisms. Bench scale remediation techniques often produce less sediment than is required to perform the standardized sediment methods and the excess sediments that are generated present...

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

    SciTech Connect

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

    1986-01-01

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

  7. 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.

  8. TOXIC SUBSTANCES CONTROL ACT TEST SUBMISSIONS (TSCATS)

    EPA Science Inventory

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

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

    PubMed Central

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

    2013-01-01

    This study reports the effects of upconversion nanoparticles (UCNPs) LaF3:Yb,Er on zebrafish, with the aim of investigating UCNPs toxicity. LaF3:Yb,Er were prepared by an oleic acid/ionic liquid two-phase system, and characterized by transmission electron microscope and X-ray powder diffraction. 140 zebrafish embryos were divided into six test groups and one control group, and respectively were injected into 5, 25, 50, 100, 200, 400 μg/mL LaF3:Yb,Er@SiO2 solution, and respectively were raised for 5 days. Each experiment was repeated ten times. Results showed that water-soluble LaF3:Yb,Er were successfully prepared, and did not exhibit obvious toxicity to zebrafish embryos under 100 μg/mL, but exhibited chronic toxicities 200 μg/mL in vivo, resulting in malformations and delayed hatching rate and embryonic and larval development. The excretion channels of LaF3:Yb,Er in adult zebrafish were mainly found in the intestine after being injected evenly for 24 h. In conclusion, the exploration of LaF3:Yb,Er for in vivo applications in animals and humans must consider UCNPs biocompatibility. PMID:23606912

  10. 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.

  11. 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

  12. Assessing the toxicity of chemical compounds associated with land-based marine fish farms: the sea urchin embryo bioassay with Paracentrotus lividus and Arbacia lixula.

    PubMed

    Carballeira, C; De Orte, M R; Viana, I G; Delvalls, T A; Carballeira, A

    2012-08-01

    In aquaculture, disinfection of facilities, prevention of fish diseases, and stimulation of fish growth are priority goals and the most important sources of toxic substances to the environment, together with excretory products from fish. In the present study, embryos of two species of sea urchin (Paracentrotus lividus and Arbacia lixula) were exposed to serial dilutions of six antibiotics (amoxicillin (AMOX), ampicillin, flumequine (FLU), oxytetracycline (OTC), streptomycin (ST), and sulfadiazine [SFD]) and two disinfectants (sodium hypochlorite (NaClO) and formaldehyde [CH(2)O]). Alterations in larval development were studied, and the effective concentrations (ECs) were calculated to evaluate the toxicity of the substances. Both species showed similar sensitivities to all substances tested. Disinfectants (EC(50) = 1.78 and 1.79 mg/l for CH(2)O; EC(50) = 10.15 and 11.1 mg/l for NaClO) were found to be more toxic than antibiotics. AMOX, OTC, and ST caused <20 % of alterations, even at the highest concentrations tested. FLU was the most toxic to P. lividus (EC(50) = 31.0 mg/l) and SFD to A. lixula (EC(50) = 12.7 mg/l). The sea urchin bioassay should be considered within toxicity assessment-monitoring plans because of the sensitivity of larvae to disinfectants. PMID:22562751

  13. 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.

  14. 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. PMID:25477153

  15. 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

  16. Comparative toxicities of aluminum and zinc from sacrificial anodes or from sulfate salt in sea urchin embryos and sperm.

    PubMed

    Caplat, Christelle; Oral, Rahime; Mahaut, Marie-Laure; Mao, Andrea; Barillier, Daniel; Guida, Marco; Della Rocca, Claudio; Pagano, Giovanni

    2010-09-01

    The toxicity of aluminum or zinc from either sacrificial anodes (SA) or their sulfate salts (SS) was evaluated in sea urchin (Paracentrotus lividus) embryos or sperm exposed to Al(III) or Zn(II) (SA or SS, 0.1-10 microM), scoring developmental defects (DDs), fertilization rate (FR), and mitotic abnormalities. A significant DD increase was observed in SS, but not SA Al(III)- and Zn(II)-exposed embryos vs. controls. Both Al(III) and Zn(II), up to 10 microM, from SA and SS, inhibited mitotic activity and induced mitotic aberrations in exposed embryos. SA-Al(III)-exposed sperm displayed a significant FR increase, unlike Al(III) sulfate overlapping with controls. Both SA-Zn(II) and Zn(II) sulfate sperm exposure resulted in a significant FR increase. The offspring of SA-Al(III)-exposed sperm displayed a significant DD decrease, unlike Al(III) sulfate exposure. Zinc sulfate sperm exposure resulted in a significant increase in offspring DDs, whereas SA-Zn(II) sperm exposure decreased DDs. Together, exposures to SA-dissolved Al(III) or Zn(II) resulted in lesser, if any toxicity, up to hormesis, compared to SS. Studies of metal speciation should elucidate the present results. PMID:20650532

  17. 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.

  18. 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.

  19. Test systems to identify reproductive toxicants.

    PubMed

    Riecke, K; Stahlmann, R

    2000-09-01

    Experience with drugs and other xenobiotics indicates that both animal testing and epidemiological studies are necessary to provide adequate data for an estimation of risks that might be associated with exposure to a chemical substance. In this review, the pros and cons of test systems for reproductive toxicity are discussed. Usually, several studies are performed to cover the different phases of the reproductive cycle. In the preclinical development of drugs, the three so-called 'segment testing protocols' have been used for several decades now. More recently, new testing concepts have been accepted internationally which include more flexibility in implementation. Several examples of compounds with the potential for reproductive toxicity are presented in more detail in a discussion of some pitfalls of the tests for fertility (phthalates and fluoroquinolones), teratogenicity (acyclovir and protease inhibitors) and postnatal developmental toxicity (fluoroquinolones). In addition, important aspects of kinetics and metabolism as a prerequisite for a rational interpretation of results from toxicological studies are briefly discussed. In vitro assays are useful for supplementing the routinely used in vivo approaches or for studying an expected or defined effect, but they are not suitable for revealing an unknown effect of a chemical on the complex reproductive process. PMID:11021511

  20. Assessment of silver nanoparticle toxicity for common carp (Cyprinus carpio) fish embryos using a novel method controlling the agglomeration in the aquatic media.

    PubMed

    Oprsal, Jakub; Blaha, Ludek; Pouzar, Miloslav; Knotek, Petr; Vlcek, Milan; Hrda, Katerina

    2015-12-01

    Formation of agglomerates and their rapid sedimentation during aquatic ecotoxicity testing of nanoparticles is a major issue with a crucial influence on the risk assessment of nanomaterials. The present work is aimed at developing and testing a new approach based on the periodic replacement of liquid media during an ecotoxicological experiment which enabled the efficient monitoring of exposure conditions. A verified mathematical model predicted the frequencies of media exchanges which checked for formation of agglomerates from silver nanoparticles AgNP with 50 nm average size of the original colloid. In the model experiments, embryos of common carp Cyprinus carpio were exposed repeatedly for 6 h to AgNPs (5-50 μm Ag L(-1)) either under semistatic conditions (exchange of media after 6 h) or in variants with frequent media exchanges (varying from 20 to 300 min depending on the AgNP colloid concentration and the desired maximum agglomerate size of 200 or 400 nm). In contrast to other studies, where dissolved free metals are usually responsible for toxic effects, our 144-h experiments demonstrated the importance of AgNP agglomerates in the adverse effects of nanosilver. Direct adsorption of agglomerates on fish embryos locally increased Ag concentrations which resulted in pronounced toxicity particularly in variants with larger 400 nm agglomerates. The present study demonstrates the suitability of the novel methodology in controlling the conditions during aquatic nanomaterial toxicity testing. It further provided insights into the mechanisms underlying the effects of AgNP, which rank on a global scale among the most widely used nanomaterials. PMID:26233755

  1. 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. PMID:20833427

  2. 16 CFR 1500.40 - Method of testing toxic substances.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... testing toxic substances. Guidelines for testing the toxicity of substances, including testing that does not require animals, are presented in the CPSC's animal testing policy set forth in 16 CFR 1500.232. A... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Method of testing toxic substances....

  3. 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. PMID:27103609

  4. 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. PMID:24664821

  5. 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.

  6. Inadequate toxicity tests of food additive acesulfame.

    PubMed

    Karstadt, Myra

    2010-01-01

    Despite poor-quality toxicity tests, acesulfame potassium was approved by the US Food and Drug Administration (FDA) for use as an artificial sweetener. At present, acesulfame is very widely used, most frequently in blends with the most popular artificial sweetener in the US, sucralose (Splenda). Acesulfame was nominated twice (in 1996 and again in 2006) for testing in the National Toxicology Program (NTP) bioassay program. Both nominations were rejected by NTP. Rather than carry out bioassays, NTP subjected acesulfame to tests in genetically modified mice (GMM). Those GMM tests yielded results that provided no insight into potential carcinogenicity of acesulfame. It is possible that FDA discouraged NTP from conducting bioassays of acesulfame. Acesulfame should be tested in the bioassay program as soon as possible, and steps should be taken to ensure the objectivity of the bioassay nomination process. PMID:20166324

  7. 16 CFR 1500.40 - Method of testing toxic substances.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... that does not require animals, are presented in the CPSC's animal testing policy set forth in 16 CFR... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Method of testing toxic substances. 1500.40... testing toxic substances. The method of testing the toxic substances referred to in § 1500.3(c)...

  8. CHIRONOMIDAE TOXICITY TESTS--BIOLOGICAL BACKGROUND AND PROCEDURES

    EPA Science Inventory

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

  9. 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

  10. 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. PMID:24911943

  11. 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

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

    PubMed Central

    Kimm-Brinson, K L; Ramsdell, J S

    2001-01-01

    Brevetoxins are lipophilic polyether toxins produced by the red tide dinoflagellate Gymnodinium breve, and their neurotoxic effects on adult animals have been documented. In this study, we characterized adverse developmental effects of brevetoxin-1 (PbTx-1) using an exposure paradigm that parallels the maternal oocyte transfer of toxin. Medaka fish (Oryzias latipes) embryos were exposed to PbTx-1 via microinjection of toxin reconstituted in a triolein oil droplet. Embryos microinjected with doses of 0.1-8.0 ng/egg (ppm) of brevetoxin-1 exhibited pronounced muscular activity (hyperkinesis) after embryonic day 4. Upon hatching, morphologic abnormalities were commonly found in embryos at the following lowest adverse effect levels: 1.0-3.0 ppm, lateral curvature of the spinal column; 3.1-3.4 ppm, herniation of brain meninges through defects in the skull; and 3.4-4.0 ppm, malpositioned eye. Hatching abnormalities were also commonly observed at brevetoxin doses of 2.0 ppm and higher with head-first, as opposed to the normal tail-first, hatching, and doses > 4.1 ng/egg produced embryos that developed but failed to hatch. Given the similarity of developmental processes found between higher and lower vertebrates, teratogenic effects of brevetoxins have the potential to occur among different phylogenetic classes. The observation of developmental abnormalities after PbTx-1 exposure identifies a new spectrum of adverse effects that may be expected to occur following exposure to G. breve red tide events. PMID:11335186

  13. 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...

  14. Chemical enhancement of SA7 virus transformation of hamster embryo cells: evaluation by interlaboratory testing of diverse chemicals.

    PubMed

    Hatch, G G; Anderson, T M; Lubet, R A; Kouri, R E; Putman, D L; Cameron, J W; Nims, R W; Most, B; Spalding, J W; Tennant, R W

    1986-01-01

    Twelve chemicals from diverse structural classes were tested under code for their capacity to enhance the transformation of Syrian hamster embryo cells by simian adenovirus SA7 in two independent laboratories. Pretreatment of hamster cells with eight of those chemicals (reserpine, dichlorvos, methapyrilene hydrochloride, benzidine dihydrochloride, diphenylhydantoin, cinnamyl anthranilate, 11-aminoundecanoic acid, and 4,4'-oxydianiline) produced repeatable enhancement of SA7 transformation at two or more consecutive dose levels, which constitutes clear evidence of enhancing activity in this assay. Both toxic and nontoxic doses of each of these chemicals caused enhancement of virus transformation. Two chemicals (2,6-dichloro-p-phenylenediamine and cinnamaldehyde) produced some evidence of enhancing activity (repeatable transformation enhancement at one dose). Dose ranges for cytotoxicity and enhancement of SA7 transformation were similar in both laboratories for all chemicals producing activity. The final two chemicals, chloramphenicol sodium succinate and ethylene thiourea, failed to reproducibly demonstrate either significant cytotoxicity or enhancement of SA7 transformation at concentrations up to 10-20 mM. The test results for these 12 chemicals were combined with the test results for 9 known carcinogens and noncarcinogens in order to evaluate relationships between activity, dose response, and lowest effective enhancing concentration for these compounds, as well as to correlate them with rodent carcinogenesis classifications. The Syrian hamster embryo cell-SA7 system demonstrated reproducible test responses in both intra- and interlaboratory studies and detected 13 out of 15 known rodent carcinogens. PMID:3732194

  15. 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.

  16. 40 CFR 797.1400 - Fish acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Fish acute toxicity test. 797.1400 Section 797.1400 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1400 Fish acute toxicity test. (a) Purpose. This...

  17. 40 CFR 797.1300 - Daphnid acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Daphnid acute toxicity test. 797.1300 Section 797.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1300 Daphnid acute toxicity test. (a) Purpose....

  18. 40 CFR 795.120 - Gammarid acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Gammarid acute toxicity test. 795.120 Section 795.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) PROVISIONAL TEST GUIDELINES Provisional Environmental Effects Guidelines § 795.120 Gammarid acute toxicity test....

  19. 40 CFR 797.1930 - Mysid shrimp acute toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Mysid shrimp acute toxicity test. 797.1930 Section 797.1930 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1930 Mysid shrimp acute toxicity test. (a)...

  20. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Daphnid chronic toxicity test. 797.1330 Section 797.1330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1330 Daphnid chronic toxicity test. (a) Purpose....

  1. 16 CFR 1500.40 - Method of testing toxic substances.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Method of testing toxic substances. 1500.40... testing toxic substances. The method of testing the toxic substances referred to in § 1500.3(c) (1)(ii)(C... with additional strips and should fit snugly around the trunk of the animal. The ends of the sleeve...

  2. 16 CFR 1500.40 - Method of testing toxic substances.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Method of testing toxic substances. 1500.40... testing toxic substances. The method of testing the toxic substances referred to in § 1500.3(c) (1)(ii)(C... with additional strips and should fit snugly around the trunk of the animal. The ends of the sleeve...

  3. 16 CFR 1500.40 - Method of testing toxic substances.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Method of testing toxic substances. 1500.40... testing toxic substances. The method of testing the toxic substances referred to in § 1500.3(c) (1)(ii)(C... with additional strips and should fit snugly around the trunk of the animal. The ends of the sleeve...

  4. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Algal acute toxicity test. 797.1050 Section 797.1050 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1050 Algal acute toxicity test. (a) Purpose. The...

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

    EPA Science Inventory

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

  6. 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...

  7. Role of oxidative stress and antioxidant defense in 3,3',4,4',5-pentachlorobiphenyl-induced toxicity and species-differential sensitivity in chicken and duck embryos.

    PubMed

    Jin, X; Kennedy, S W; Di Muccio, T; Moon, T W

    2001-05-01

    The role of oxidative stress and antioxidant defense in 3,3',4,4',5-pentachlorobiphenyl (PCB 126)-induced toxicity and species-specific sensitivity was examined in White Leghorn chicken (Gallus domesticus) and Pekin duck (Anas platyrhynchos) embryos. Eggs were injected into the air cell with 0.4-1.6 microgram PCB 126/kg egg in corn oil prior to incubation. Lipid peroxidation measured by thiobarbituric acid reactive substances (TBARS), the GSSG:GSH ratio, and glutathione peroxidase (GPox) activities were determined in liver and adipose tissue of day 19 chicken and day 26 duck embryos. In chicken embryos, PCB 126 increased mortality and the incidence of edema and liver lesions, decreased embryo size, increased eye and head malformations, and markedly reduced fat storage. In contrast, no effects on the endpoints were observed in duck embryos even at the highest dose used in chicken embryos. PCB 126 increased hepatic 7-ethoxyresorufin-O-deethylase (EROD) activity in a dose-dependent manner in chicken but not duck embryos. PCB 126 significantly increased TBARS levels in liver and to a greater degree in adipose tissue of chicken embryos, indicating that adipose tissue is a sensitive target for this compound. Increases in lipid peroxidation by PCB 126 were associated with significant decreases in GPox activity in these tissues. These biochemical changes support oxidative stress playing a role in PCB 126-induced embryo toxicity while antioxidant defenses provided protection against oxidative damage induced by this compound. Ducks, the less-sensitive species, showed higher basal levels of hepatic GPox than chickens, suggesting that this antioxidant enzyme may contribute to the differences in sensitivity to this compound between the two species. PMID:11312653

  8. SAND SPIKED WITH COPPER AS A REFERENCE TOXICANT MATERIAL FOR SEDIMENT TOXICITY TESTING: A PRELIMINARY EVALUATION

    EPA Science Inventory

    Routine use of solid-phase sediment toxicity tests for scientific and regulatory purposes necessitates the development of solid-phase reference toxicant materials. n order to evaluate an approach for developing such materials, 12 solid-phase 96-h reference toxicant tests were con...

  9. 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

  10. Albendazole sulphoxide enantiomers in pregnant rats' embryo concentrations and developmental toxicity.

    PubMed

    Capece, B P S; Navarro, M; Arcalis, T; Castells, G; Toribio, L; Perez, F; Carretero, A; Ruberte, J; Arboix, M; Cristòfol, C

    2003-05-01

    Three single oral doses (8.5, 10, and 14 mg/kg) of a racemic formulation of albendazole sulphoxide (ABZSO) were administered to pregnant rats on day 10 of gestation. Mother plasma and embryo concentrations of ABZSO enantiomers and albendazole sulphone (ABZSO(2)) were determined 9 h after administration. The (-)-ABZSO enantiomer showed higher peak concentrations in both maternal plasma and embryo than the (+) enantiomer. An increase in embryo concentrations of ABZSO enantiomers and ABZSO(2) was only observed when dose rose to 14 mg/kg. There was an increase in resorption when the dose increased, but significant differences were only found in the higher dose group when compared with the other groups. The incidence of external and skeletal malformations (mostly of the tail, vertebrae and ribs) rose significantly in the 10 mg/kg group, producing almost 20% and 90% of malformed fetuses, respectively, and gross external and skeletal abnormalities in the thoracic region and limbs were also found. PMID:12672373

  11. 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...

  12. 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...

  13. 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. PMID:26575636

  14. 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

  15. Rapid in vivo testing of drug response in multiple myeloma made possible by xenograft to turkey embryos

    PubMed Central

    Farnoushi, Y; Cipok, M; Kay, S; Jan, H; Ohana, A; Naparstek, E; Goldstein, R S; Deutsch, V R

    2011-01-01

    Background: The best current xenograft model of multiple myeloma (MM) in immune-deficient non-obese diabetic/severe-combined immunodeficient mice is costly, animal maintenance is complex and several weeks are required to establish engraftment and study drug efficacy. More practical in vivo models may reduce time and drug development cost. We recently described a rapid low-cost xenograft model of human blood malignancies in pre-immune turkey. Here, we report application of this system for studying MM growth and the preclinical assessment of anticancer therapies. Methods: Cell lines and MM patient cells were injected intravenously into embryonic veins on embryonic day 11 (E11). Engraftment of human cells in haematopoietic organs was detected by quantitative real-time polymerase chain reaction, immunohistochemistry, flow cytometry and circulating free light chain. Results: Engraftment was detected after 1 week in all embryos injected with cell lines and in 50% of those injected with patient cells. Injection of bortezomib or lenalinomide 48 h after cell injection at therapeutic levels that were not toxic to the bone marrow dramatically reduced MM engraftment. Conclusion: The turkey embryo provides a practical, xenograft system to study MM and demonstrates the utility of this model for rapid and affordable testing therapeutics in vivo. With further development, this model may enable rapid, inexpensive personalised drug screening. PMID:22045188

  16. Optimization of culturing conditions for toxicity testing with the alga Oophila sp. (Chlorophyceae), an amphibian endosymbiont.

    PubMed

    Rodríguez-Gil, José Luis; Brain, Richard; Baxter, Leilan; Ruffell, Sarah; McConkey, Brendan; Solomon, Keith; Hanson, Mark

    2014-11-01

    Eggs of the yellow-spotted salamander (Ambystoma maculatum) have a symbiotic relationship with green algae. It has been suggested that contaminants that are preferentially toxic to algae, such as herbicides, may impair the symbiont and, hence, indirectly affect the development of the salamander embryo. To enable testing under near-standard conditions for first-tier toxicity screening, the authors isolated the alga from field-collected eggs and identified conditions providing exponential growth rates in the apparent asexual phase of the alga. This approach provided a uniform, single-species culture, facilitating assessment of common toxicity end points and comparison of sensitivity relative to other species. Sequencing of the 18s ribosomal DNA indicated that the isolated alga is closely related to the recently described Oophila amblystomatis but is more similar to other known Chlamydomonas species, suggesting possible biogeographical variability in the genetic identity of the algal symbiont. After a tiered approach to culturing method refinement, a modified Bristol's media with 1 mM NH4 (+) as nitrogen source was found to provide suitable conditions for toxicity testing at 18 °C and 200 µmol m(-2) s(-1) photosynthetically active radiation (PAR) on a 24-h light cycle. The validity of the approach was demonstrated with Zn(2+) as a reference toxicant. Overall, the present study shows that screening for direct effects of contaminants on the algal symbiont without the presence of the host salamander is possible under certain laboratory conditions. PMID:25113146

  17. 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.

  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. In vitro Toxicity Testing in the Twenty-First Century

    PubMed Central

    Roggen, Erwin L.

    2011-01-01

    The National Research Council (NRC) article “Toxicity Testing in the 21st Century: A vision and A Strategy” (National Research Council, 2007) was written to bring attention to the application of scientific advances for use in toxicity tests so that chemicals can be tested in a more time and cost efficient manner while providing a more relevant and mechanistic insight into the toxic potential of a compound. Development of tools for in vitro toxicity testing constitutes an important activity of this vision and contributes to the provision of test systems as well as data that are essential for the development of computer modeling tools for, e.g., system biology, physiologically based modeling. This article intends to highlight some of the issues that have to be addressed in order to make in vitro toxicity testing a reality in the twenty-first century. PMID:21713102

  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. 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

  2. STATUS AND APPLICATIONS OF ECHINOID (PHYLUM ECHINODERMATA) TOXICITY TEST METHODS

    EPA Science Inventory

    The use of echinoderms for toxicity testing has focused primarily on sea urchins and sand dollars (Strongylocentrolus purpuratus, Arbacia punctulata, Lytechinus pictus, and Dendraster excentricus, for example). he status and relative sensitivity of various test methods are descri...

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

    PubMed

    Jomaa, Barae; Hermsen, Sanne A B; Kessels, Maurijn Y; van den Berg, Johannes H J; Peijnenburg, Ad A C M; Aarts, Jac M M J G; Piersma, Aldert H; Rietjens, Ivonne M C M

    2014-01-01

    Zebrafish embryos were exposed to concentration ranges of selected thyroid-active model compounds in order to assess the applicability of zebrafish-based developmental scoring systems withinan alternative testing strategy to detect the developmental toxicity ofthyroid-active compounds. Model compounds tested included triiodothyronine (T3), propylthiouracil (PTU), methimazole (MMI), sodium perchlorate (NaClO4) and amiodarone hydrochloride (AMI), selected to represent different modes of action affecting thyroid activity. Tested time windows included 48-120 hours post fertilization (hpf), 0-72 hpf and 0-120 hpf. All tested compounds resulted in developmental changes, with T3 being the most potent. The developmental parameters affected included reflective iridophores, beat and glide swimming, inflated swim bladders, as well as resorbed yolk sacs. These effects are only evident by 120 hpf and therefore an existing General Morphology Score (GMS) system was extended to create a General Developmental Score(GDS) that extends beyond the 72 hpfscoring limit of GMS and includes additional parameters that are affected by exposure to model thyroid-active compounds. Moreover, the GDS is cumulative as it includes not only the scoring of developmental morphologies but also integrates developmental dysmorphologies. Exposures from 48-120 hpf did not provide additional information to exposures from 0-120 hpf. The results indicate that the zebrafish GDS can detect the developmental toxicity of thyroid toxicants and may be of use in an integrated testing strategy to reduce, refine and in certain cases replace animal testing. PMID:24793664

  4. 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. PMID:25269881

  5. 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

  6. Toxicity Tests for Ensuring Succesful Industrial Wastewater Treatment Plant Operation

    NASA Astrophysics Data System (ADS)

    Cěbere, B.; Faltiņa, E.; Zelčāns, N.; Kalniņa, D.

    2009-01-01

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

  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. 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.

  9. 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

  10. Extrapolation of toxic indices among test objects.

    PubMed

    Tichý, Miloň; Rucki, Marián; Roth, Zdeněk; Hanzlíková, Iveta; Vlková, Alena; Tumová, Jana; Uzlová, Rút

    2010-12-01

    Oligochaeta Tubifex tubifex, fish fathead minnow (Pimephales promelas), hepatocytes isolated from rat liver and ciliated protozoan are absolutely different organisms and yet their acute toxicity indices correlate. Correlation equations for special effects were developed for a large heterogeneous series of compounds (QSAR, quantitative structure-activity relationships). Knowing those correlation equations and their statistic evaluation, one can extrapolate the toxic indices. The reason is that a common physicochemical property governs the biological effect, namely the partition coefficient between two unmissible phases, simulated generally by n-octanol and water. This may mean that the transport of chemicals towards a target is responsible for the magnitude of the effect, rather than reactivity, as one would assume suppose. PMID:21331180

  11. Extrapolation of toxic indices among test objects

    PubMed Central

    Tichý, Miloň; Rucki, Marián; Roth, Zdeněk; Hanzlíková, Iveta; Vlková, Alena; Tumová, Jana; Uzlová, Rút

    2010-01-01

    Oligochaeta Tubifex tubifex, fish fathead minnow (Pimephales promelas), hepatocytes isolated from rat liver and ciliated protozoan are absolutely different organisms and yet their acute toxicity indices correlate. Correlation equations for special effects were developed for a large heterogeneous series of compounds (QSAR, quantitative structure-activity relationships). Knowing those correlation equations and their statistic evaluation, one can extrapolate the toxic indices. The reason is that a common physicochemical property governs the biological effect, namely the partition coefficient between two unmissible phases, simulated generally by n-octanol and water. This may mean that the transport of chemicals towards a target is responsible for the magnitude of the effect, rather than reactivity, as one would assume suppose. PMID:21331180

  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. 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.

  14. 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.

  15. 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.

  16. Acute oral toxicity test of chemical compounds in silkworms.

    PubMed

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

    2016-02-01

    This study performed an acute oral toxicity test of 59 compounds in silkworms. These compounds are listed in OECD guidelines as standard substances for a cytotoxicity test, and median lethal dose (LD(50)) werecalculated for each compound. Acute oral LD(50) values in mammals are listed in OECD guidelines and acute oral LD(50) values in silkworms were determined in this study. R(2) for the correlation between LD(50) values in mammals and LD(50) values in silkworms was 0.66. In addition, the acute oral toxicity test in silkworms was performed by two different facilities, and test results from the facilities were highly reproducible. These findings suggest that an acute oral toxicity test in silkworms is a useful way to evaluate the toxicity of compounds in mammals. PMID:26971557

  17. 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.

  18. 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...

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

    EPA Science Inventory

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

  20. MANUAL FOR THE EVALUATION OF LABORATORIES PERFORMING AQUATIC TOXICITY TESTS

    EPA Science Inventory

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

  1. 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...

  2. UTILITY OF SHORT-TERM TESTS FOR GENETIC TOXICITY

    EPA Science Inventory

    By definition, short-term test (STTs) for genetic toxicity detect genotoxic agents, not carcinogens specifically. owever, there is ufficient evidence, based on mechanistic considerations alone, to say that genotoxic agents are potential carcinogens. TTs have high statistical powe...

  3. 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. PMID:23821235

  4. 40 CFR 797.1600 - Fish early life stage toxicity test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... embryo cups into the test chambers. (B) For brook trout and rainbow trout a test begins when newly... initiation of the test. (D) When embryos are received from an outside culture source (i.e., rainbow and brook... (Cyprinodon variegatus). (C) Brook trout (Salvelinus fontinalis). (D) Rainbow trout (Salmo gairdneri)....

  5. 40 CFR 797.1600 - Fish early life stage toxicity test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... embryo cups into the test chambers. (B) For brook trout and rainbow trout a test begins when newly... initiation of the test. (D) When embryos are received from an outside culture source (i.e., rainbow and brook... (Cyprinodon variegatus). (C) Brook trout (Salvelinus fontinalis). (D) Rainbow trout (Salmo gairdneri)....

  6. Neurobehavioral toxicity testing for risk assessment.

    EPA Science Inventory

    Neurobehavioral evaluations are key components in neurotoxicity testing. In the realm of regulatory testing, these evaluations range from a functional observational battery (FOB) and an Irwin’s screen, which assess the neurological, motor, and functional integrity of the subject...

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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 ...

  12. Expression of storm water runoff toxicity in three test organisms

    SciTech Connect

    Katznelson, R.; Markel, R.P.

    1995-12-31

    Storm water toxicity was monitored at numerous locations in the San Francisco Bay Area, using the EPA protocol for short-term chronic toxicity tests with freshwater organisms in the ``screening`` mode. Toxicity to Selenastrum capricomutum and Pimephales promelas was prevalent in samples collected at industrial catchments but was rarely detected in samples collected from other land use catchments. On the other hand, Ceriodaphnia dubia responded in most samples collected from industrial, commercial, residential, and transportation corridor catchments. In further analyses of C. dubia test results, the median time to lethality (LT{sub 50}) was derived to allow comparisons of the relative intensity of toxicity, and the number of offspring per female per reproductive day (OFRD) was calculated to allow separation of mortality from reproductive effects. This approach revealed that most of the moderately toxic (LT{sub 50} of 5--7 days) storm water samples collected from catchments of mixed land use (stream stations) did not inhibit reproduction, and that most storm water samples collected from transportation corridors did inhibit reproduction. Toxicity identification evaluations (TIE) indicated that diazinon is the major cause of toxicity in many stream samples, suggesting an explanation for the differential sensitivity observed in different species.

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

    PubMed

    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

    2016-04-01

    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

  14. 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

  15. Environmental toxicity testing of contaminated soil based on microcalorimetry.

    PubMed

    Gruiz, K; Feigl, V; Hajdu, Cs; Tolner, M

    2010-10-01

    Contaminated site assessment and monitoring requires efficient risk-management tools including innovative environmental toxicity tests. The first application of microcalorimetry for toxicity testing draw the attention to a possible new tool to increase sensitivity, to eliminate matrix effect and to study effect-mechanism. A Thermal Activity Monitor (TAM) microcalorimeter was used for measuring the heat production of various test organisms when getting in contact with sterile toxic soils. Well known bacterial (Azomonas agilis), animal (Folsomia candida) and plant test organisms (Sinapis alba) were tested for heat production. The heat response of selected testorganisms was measured in case of metal (Cu and Zn) and organic pollutant (Diesel oil, DBNPA and PCP) contaminated soils. In addition to the quantitative determination of the heat production, the mechanism of the toxic effect can be characterized from the shape of the power-time curve (slope of the curve, height and time of the maximum). In certain concentration ranges the higher the pollutant concentration of the soil the lower the maximum of the time-heat curve. At low pollutant concentrations an increased heat production was measured in case of A. agile and 20 and 200 mg Zn kg(-1) soil. The microcalorimetric testing was more sensitive in all cases than the traditional test methods. Our results showed that the microcalorimetric test method offers a new and sensitive option in environmental toxicology, both for research and routine testing. PMID:20549622

  16. Developmental toxicity testing for safety assessment: new approaches and technologies.

    PubMed

    Knudsen, Thomas B; Kavlock, Robert J; Daston, George P; Stedman, Donald; Hixon, Mary; Kim, James H

    2011-10-01

    The ILSI Health and Environmental Sciences Institute's Developmental and Reproductive Toxicology Technical Committee held a 2-day workshop entitled "Developmental Toxicology-New Directions" in April 2009. The fourth session of this workshop focused on new approaches and technologies for the assessment of developmental toxicology. This session provided an overview of the application of genomics technologies for developmental safety assessment, the use of mouse embryonic stem cells to capture data on developmental toxicity pathways, dynamical cell imaging of zebrafish embryos, the use of computation models of development pathways and systems, and finally, high-throughput in vitro approaches being utilized by the EPA ToxCast program. Issues discussed include the challenges of anchoring in vitro predictions to relevant in vivo endpoints and the need to validate pathway-based predictions with targeted studies in whole animals. Currently, there are 10,000 to 30,000 chemicals in world-wide commerce in need of hazard data for assessing potential health risks. The traditional animal study designs for assessing developmental toxicity cannot accommodate the evaluation of this large number of chemicals, requiring that alternative technologies be utilized. Though a daunting task, technologies are being developed and utilized to make that goal reachable. PMID:21770025

  17. Sensitivity and accuracy of whole effluent toxicity (WET) tests

    SciTech Connect

    Chapman, G.; Lussier, S.; Norberg-King, T.; Poucher, S.; Thursby, G.

    1995-12-31

    Direct measurement of effluent toxicity is a critical tool in controlling ambient toxicity. Lack of water quality criteria for many commonly discharged chemicals and complicated toxicological interactions in complex effluents are common. Complex effluent toxicity tests should provide limits as protective as National Criteria for single chemicals. One way to evaluate WET test sensitivity and accuracy is to compare WET test results with single chemicals to the National Criteria for these chemicals. A study of eight criteria chemicals (ammonia, analine, cadmium, carbaryl, copper, lead, methyl parathion, and zinc), two freshwater WET tests (Pimephales and Ceriodaphnia), and four marine WET tests (Arbacia, Champia, Menidia, and Mysidopsis) was conducted to provide this comparison. The most sensitive of the freshwater and marine WET tests with each chemical were generally less protective than the National Final Chronic Value (FCV) concentration by factors ranging from 1.09 to 44. Less-sensitive WET tests with each chemical represented significant underestimation of chronic toxicity by factors often in the range of 100--10,000. In two instances WET test results (copper and Champia, zinc and Ceriodaphnia) were below FCV by factors of 1.85 and 3.4, respectively. It is recognized that Champia is extremely sensitive to copper and that Daphnids may not be protected by the current National zinc criterion, thus these results are not surprising. Adequate accuracy for WET tests usually requires that the most sensitive WET-test species by utilized. Although the bias of WET tests to underestimate chronic toxicity is relatively small, it should be considered in the selection of test endpoints and application of WET data.

  18. 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

  19. 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.

  20. 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.

  1. 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...

  2. 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...

  3. SIMPLIFIED FEEDING TECHNIQUES FOR CULTURING AND TOXICITY TESTING WITH 'CERIODAPHNIA'

    EPA Science Inventory

    Food used for Ceriodaphnia dubia in culture and toxicity testing should be uniform, adequate, and easily prepared. Using as a control the current standard food, YCTF, the authors tested a variety of foods made with algal species singly and in combination, prepared with several me...

  4. APPROPRIATE DURATIONS AND MEASURES FOR 'CERIODAPHNIA' TOXICITY TESTS

    EPA Science Inventory

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

  5. THE ROLE OF INORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING

    EPA Science Inventory

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

  6. 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...

  7. PREPARATION OF BENTHIC SUBSTRATES FOR SEDIMENT TOXICITY TESTING

    EPA Science Inventory

    A jar-rolling apparatus was constructed to prepare test substrates using sediments spiked with laboratory chemicals, the toxicity of which were assessed with the Rhepoxynius abronius bioassay. Test sediments were mixed by rolling them for several hours in one-gallon glass jars. M...

  8. Results of chronic toxicity tests conducted on selected A-area outfalls, June-August 1996

    SciTech Connect

    Specht, W.L.

    1997-07-01

    In anticipation of possible toxicity testing requirements in the SRS`s new (1996) NPDES permit, toxicity tests were performed at selected A-Area NPDES outfalls in order to determine if the outfalls were toxic. Chronic definitive toxicity tests were conducted on Ceriodaphnia dubia using water collected from nine locations during the summer of 1996. Six of the nine locations were toxic.

  9. 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

  10. Developmental toxicity testing of biopharmaceuticals in nonhuman primates: previous experience and future directions.

    PubMed

    Martin, Pauline L; Weinbauer, Gerhard F

    2010-12-01

    Developmental toxicity studies for pharmaceutical safety testing are designed to evaluate potential adverse effects of drug treatment on pregnancy and on the developing embryo/fetus. Biopharmaceuticals present specific challenges for developmental toxicity testing because the pharmacology of these molecules, which are frequently human-specific proteins, is often restricted to humans and nonhuman primates (NHPs). For those species-restricted molecules, the only option for the evaluation of potential effects on development of the human biopharmaceutical is to use NHPs. This article reviews each of the stages of development in cynomolgus macaques (the most frequently used NHP) and the potential exposure of the embryo, fetus, and infant following administration of a biopharmaceutical during pregnancy and lactation. Because the purpose of the NHP developmental studies is to identify potential human risks, a comparison between macaque and human development and potential exposure has been made when possible. Understanding the potential exposure of the conceptus relative to critical periods in development is essential to designing a scientifically based study that adequately addresses human risks. Some options for NHP study designs, including the option of combining end points into a single study, and the pros and cons of each of the study options have been reviewed. Developmental studies for biopharmaceuticals in NHPs need to be optimally designed on a case-by-case basis taking into consideration the pharmacology of the molecule, the type of molecule (antibody or non-antibody), the potential exposure relative to the development of potential target organs, the clinical use, and the ethical considerations associated with the use of NHPs. PMID:20926830

  11. 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.

  12. Sensitivity and precision of whole effluent toxicity (WET) tests

    SciTech Connect

    Denton, D.; Chapman, G.; Fulk, F.

    1995-12-31

    The US Environmental Protection Agency`s test method manuals recommend reference toxicant test be performed to determine test sensitivity and precision within a test and among tests over time. The levels of intra and interlaboratory precision with two reference toxicants (zinc and copper) were examined with six marine test species (Macrocystis pyrifera, Haliotis rufescens, Strongylocentrotus purpuratus, Dendraster excentricus, Mytilus spp., and Menidia beryllina) and with two freshwater test species (Ceriodaphnia dubia and Pimephales promelas). Data from the EPA`s Reference Toxicant Database were used in the analysis. Data was used if the tests met the specified test acceptability criteria. The test sensitivity was examined by calculation of the minimum significant difference (e.g. MSD) and will be discussed. Results were compared to the national final chronic value (FCV) for copper and zinc. Greater than 99% of the EC25 values were above the FCV for copper with Strongylocentrotus purpuratus, Dendraster excentricus and Macrocystis pyrifera. However, greater than 99% of the EC25 values were below the FCV for zinc with Haliotis rufescens.

  13. A modified toxicity testing method using tropical marine microalgae.

    PubMed

    Ismail, Melor; Phang, Siew-Moi; Tong, Soo-Loong; Brown, Murray T

    2002-04-01

    Toxicity testing of four heavy metals (Cd, Cu, Mn and As) using four species of tropical marine phytoplankton, Chaetoceros calcitrans, Isochrysis galbana, Tetraselmis tetrahele and Tetraselmis sp., was carried out in multiwell plates with test volumes of 2 mL and the results compared to those of standard, large volume, shake-flasks. IC50 values (concentrations of metals estimated to inhibit 50% growth relative to the control) were determined after 96 hours based on automated O.D. readings measured in Elisa microplates by a Multiskan spectrophotometer. Good agreement was achieved between O.D. readings and cell counts indicating that this new method is a simple, economical, practical and rapid technique for toxicity testing, and provides good reproducibility of IC50 values. Results of the toxicity tests indicate that Cu was the most toxic metal (average IC50 values ranging from 0.04 to 0.37 mg L(-1)), followed by Cd (0.06-5.7 mg L(-1)), Mn (7.2-21.4 mg L(-1)) and As (33.9-319.3 mg L(-1)). Test species had different degrees of sensitivity to the metals tested, with I. galbana and C. calcitrans the most sensitive to Cu, Cd and Mn. Based on these findings it is recommended that the existing Malaysian Interim Standards for Marine Water Quality for Cd and Cu be reviewed. PMID:12002283

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. Guidelines for developmental toxicity testing of chemicals in Japan

    SciTech Connect

    Tanimura, T.

    1985-11-01

    With the definition of teratogenicity expanded in terms of the developmental stages when an agent acts and the types of developmental anomalies induced, the concept of developmental toxicity has been established. The examination of functional developmental disorders including behavior has become one of the most important items for the evaluation of developmental toxicity of chemicals, especially pharmaceutical drugs. The guidelines for developmental toxicity testing of drugs in Japan stress the need for examination of growth and development including behavior and fertility on the postweaning offspring. The outline of the Japanese guidelines is presented and it is emphasized that studies should be done as research and include self evaluation of the scientific truth of the experiment and extrapolation to humans. In addition, the activities of the Behavioral Teratology Meeting, a satellite meeting to the Japanese Teratology Society, are introduced and enquete surveys of the Japan Pharmaceutical Manufacturers Association and collaborative studies for the standardization of learning tests in Japan are briefly presented.

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

    PubMed

    Gaytán, Brandon D; Vulpe, Chris D

    2014-01-01

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

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

    PubMed Central

    Gaytán, Brandon D.; Vulpe, Chris D.

    2014-01-01

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

  1. 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

  2. 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...

  3. 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.

  4. 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

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

    EPA Science Inventory

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

  6. COMPUTER INTERFACED TOXICITY TESTING SYSTEM FOR SIMULATING VARIABLE EFFLUENT LOADING

    EPA Science Inventory

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

  7. THE FUTURE OF TOXICITY TESTING AND ASSESSMENT OF ENVIRONMENTAL AGENTS

    EPA Science Inventory

    The National Research Council's Board on Environmental Studies and Toxicology is conducting a two-part study to assess and advance current approaches to toxicity testing and assessment to meet regulatory data needs. The first part of the study was completed January 2006, in which...

  8. 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. PMID:26168280

  9. A FIELD VALIDATION OF TWO SEDIMENT-AMPHIPOD TOXICITY TESTS

    EPA Science Inventory

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

  10. 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.

  11. Joint toxic actions of organic flocculating polymers: Impact on Whole Effluent Toxicity testing. Part 3

    SciTech Connect

    Fort, D.J.; Stover, E.L.

    1996-11-01

    Most states and/or US Environmental Protection Agency (EPA) regions have adopted narrative water quality criteria requiring various forms of Whole Effluent Toxicity (WET) testing as a component of the National Pollutant Discharge Elimination System (NPDES) discharge criteria. Because polymers and inorganic coagulant aids are commonly used in conjunction with one another for wastewater treatment, an assessment of potential interactions between the two types of additives was warranted. Thus, joint-compound interaction studies with both the polymer and FeCl{sub 3} or Al{sub 2}(SO{sub 4}){sub 3} were conducted to determine the effect of co-treatment on WET. Results from these studies clearly demonstrated that the toxicity of these additives during combined treatment was much more dramatic than for each compound individually and that individual toxic assessment would not account for the total magnitude of toxicity induced during combined treatment. Combinations of flocculating polymers with different physical/chemical characteristics (i.e., chemical structure, molecular weight, hydrophobicity, molar refractivity, and charge density) are also commonly used in wastewater treatment. Thus, joint-polymer action studies with several polymer mixtures were performed. Polymers used in these studies included cationic polyquaternary amine (PQA), cationic epichlorohydrin/dimethylamine (EPI/DMA), anionic polyacrylamide (A-PAM), and non-ionic polyacrylamide (N-PAM) polymers. Results from these studies are presented in this manuscript. Overall, results from these studies indicated that the type of polymer mixture was important in determining the joint toxic actions of the flocculating polymers.

  12. 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…

  13. Insect (Locusta migratoria migratorioides) test monitoring the toxicity of cyanobacteria.

    PubMed

    Hiripi, L; Nagy, L; Kalmár, T; Kovács, A; Vörös, L

    1998-01-01

    An insect test was developed to investigate the toxicity of cyanobacteria. The African locust, Locusta migratoria migratorioides R.F. was used as a test animal instead of mouse. The cyanobacteria tested were Aphanizomenon flos-aque, Anabaena aphanizomenoides, Cylindrospermopsis raciborskii, Microcystis aeruginosa. The toxicity of authentic microcystin-LR was also tested. Cyanobacteria producing toxins killed the animals when the homogenized cell suspension was injected into the animals. The locust test proved to be more sensitive than the mouse test. The LD50 values of the different cyanobacteria for locusts and for mice, respectively were the following: 90 microg/animal (60 mg/kg) and 8000 microg/animal (320 mg/kg), for Aphanizomenon flos-aquae; 255 microg/animal (170.2 mg/kg) and 3750 microg/animal (150 mg/kg), for Anabaena aphanizomenoides; 195 microg/animal (131.4 mg/kg) and 5750 microg/animal (230 mg/kg), for Cylindrospermopsis raciborskii; 22.5 microg/animal (15 mg/kg) and 6000 microg/ animal (240 mg/kg), for Microcystis aeruginosa. In locusts the LD50 value for authentic microcystin-LR was 0.2 microg/animal (130 mg/kg). Since the weight of the mice is 15 to 20 times larger than that of the locusts, hence less toxic cells are needed to kill the locusts. The locust test is cheaper than the mouse test, large number of animals can be used in the experiments and the LD50 values can be estimated more precisely. The toxicity of C. raciborskii was significantly lower when the lyophilized cells were extracted in methanol (LD50 = 767 mg/kg), instead of NaCl solution (LD50 = 131.4 mg/kg). PMID:9745918

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. [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

  19. 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

  20. 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.

  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. PMID:26256397

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

    EPA Science Inventory

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

  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. Sugars exert a major influence on the vitrification properties of ethylene glycol-based solutions and have low toxicity to embryos and oocytes.

    PubMed

    Kuleshova, L L; MacFarlane, D R; Trounson, A O; Shaw, J M

    1999-03-01

    A systematic approach was taken to assess the vitrification properties of ethylene glycol-based solutions supplemented with carbohydrates. Solutions were prepared by weight (gravimetrically) using ethylene glycol as the cryoprotectant, 0.9% NaCl in water, and six different sugars: d-glucose, d(-)-fructose, d-sorbitol, sucrose, d(+)-trehalose, and raffinose. Sugars were added on a molal basis (0. 1, 0.5, and 1 m). Characteristics of the solutions were measured during warming by differential scanning calorimetry using a cooling rate of 100 degrees C/min and a warming rate of 10 degrees C/min. In the absence of carbohydrates a 59 wt% EG-saline solution formed a stable glass. When EG was replaced by an equimolal concentration of glucose, fructose, or sorbitol (monosaccharides) at 0.1, 0.5, or 1.0 m there was no change in the total solute concentration at which vitrification occurred, but the glass transition (Tg) occurred at a higher temperature than in EG-saline alone. When EG was replaced by an equimolal concentration of sucrose or trehalose (disaccharides) both the Tg and the lowest total solute concentration required for vitrification became progressively higher as the molecular weight, or the ratio of sugar to EG in the solutions, increased. At the highest tested disaccharide concentration (1 m) vitrification was achieved at a total solute concentration of 65 wt% (sucrose) and 67 wt% (trehalose). The polysaccharide raffinose significantly modified the vitrification properties of ethylene glycol solutions. When 0.5 or 0.1 m raffinose replaced EG on an equimolal basis the glass transition point was raised more than with either the monosaccharides or the disaccharides. Raffinose allowed vitrification at a total solute concentration of 67 wt% (0.5 m) and 63 wt% (0.1 m). The maturation of immature mouse oocytes, and the development of embryos in media containing 5-7 mM of any sugar was comparable to controls, indicating that they are not toxic. Exposure of freshly

  5. Species-specific considerations in using the fish embryo test as an alternative to identify endocrine disruption.

    PubMed

    Schiller, Viktoria; Zhang, Xiaowei; Hecker, Markus; Schäfers, Christoph; Fischer, Rainer; Fenske, Martina

    2014-10-01

    A number of regulations have been implemented that aim to control the release of potentially adverse endocrine disrupters into the aquatic environment based on evidence from laboratory studies. Currently, such studies rely on testing approaches with adult fish because reliable alternatives have not been validated so far. Fish embryo tests have been proposed as such an alternative, and here we compared two species (medaka and zebrafish) to determine their suitability for the assessment of substances with estrogenic and anti-androgenic activity. Changes in gene expression (in here the phrase gene expression is used synonymously to gene transcription, although it is acknowledged that gene expression is additionally regulated, e.g., by translation and protein stability) patterns between the two species were compared in short term embryo exposure tests (medaka: 7-day post fertilization [dpf]; zebrafish: 48 and 96h post fertilization [hpf]) by using relative quantitative real-time RT-PCR. The tested genes were related to the hypothalamic-gonadal-axis and early steroidogenesis. Test chemicals included 17α-ethinylestradiol and flutamide as estrogenic and anti-androgenic reference compounds, respectively, as well as five additional substances with endocrine activities, namely bisphenol A, genistein, prochloraz, linuron and propanil. Estrogenic responses were comparable in 7-dpf medaka and 48/96-hpf zebrafish embryos and included transcriptional upregulation of aromatase b, vitellogenin 1 as well as steroidogenic genes, suggesting that both species reliably detected exposure to estrogenic compounds. However, anti-androgenic responses differed between the two species, with each species providing specific information concerning the mechanism of anti-androgenic disruption in fish embryos. Although small but significant changes in the expression of selected genes was observed in 48-hpf zebrafish embryos, exposure prolonged to 96hpf was necessary to obtain a response indicative

  6. 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.

  7. The environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin disrupts morphogenesis of the rat pre-implantation embryo

    PubMed Central

    Hutt, Karla J; Shi, Zhanquan; Albertini, David F; Petroff, Brian K

    2008-01-01

    Background Environmental toxicants, whose actions are often mediated through the aryl hydrocarbon receptor (AhR) pathway, pose risks to the health and well-being of exposed species, including humans. Of particular concern are exposures during the earliest stages of development that while failing to abrogate embryogenesis, may have long term effects on newborns or adults. The purpose of this study was to evaluate the effect of maternal exposure to the AhR-specific ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development of rat pre-implantation embryos with respect to nuclear and cytoskeletal architecture and cell lineage allocation. Results We performed a systematic 3 dimensional (3D) confocal microscopy analysis of rat pre-implantation embryos following maternal exposure to environmentally relevant doses of TCDD. Both chronic (50 ng/kg/wk for 3 months) and acute (50 ng/kg and 1 μg/kg at proestrus) maternal TCDD exposure disrupted morphogenesis at the compaction stage (8–16 cell), with defects including monopolar spindle formation, f-actin capping and fragmentation due to aberrant cytokinesis. Additionally, the size, shape and position of nuclei were modified in compaction stage pre-implantation embryos collected from treated animals. Notably, maternal TCDD exposure did not compromise survival to blastocyst, which with the exception of nuclear shape, were morphologically similar to control blastocysts. Conclusion We have identified the compaction stage of pre-implantation embryogenesis as critically sensitive to the effects of TCDD, while survival to the blastocyst stage is not compromised. To the best of our knowledge this is the first in vivo study to demonstrate a critical window of pre-implantation mammalian development that is vulnerable to disruption by an AhR ligand at environmentally relevant doses. PMID:18171477

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. Evaluation of the test of significant toxicity for determining the toxicity of effluents and ambient water samples.

    PubMed

    Diamond, Jerry M; Denton, Debra L; Roberts, John W; Zheng, Lei

    2013-04-01

    The test of significant toxicity (TST) is a hypothesis-testing approach based on bioequivalence developed by the U.S. Environmental Protection Agency (U.S. EPA) for analyzing whole-effluent toxicity (WET) and ambient toxicity data. The present study compares results of acute and chronic toxicity tests of effluent, storm-water, and ambient (i.e., receiving-water) samples using both the TST and the standard no-observed-effect concentration (NOEC) approach. Valid WET data were analyzed from 890 tests provided by more than 25 dischargers in California and Washington, USA, representing the majority of test methods used in the U.S. WET program. An additional 3,201 freshwater chronic toxicity tests, obtained from ambient monitoring programs in California, were also analyzed. The TST and NOEC approaches both declared a low number (<6.5%) of tests toxic if effects were below the unacceptable toxicity regulatory management decision (RMD) of 25% effect in chronic tests or 20% effect in acute tests. However, those test methods having generally lower within-test variability and greater test power (e.g., urchin fertilization test) had a much lower percentage of tests declared toxic than the NOEC approach when effects were below the unacceptable toxicity RMD. In addition, the TST showed fewer tests to be nontoxic than NOEC if the test exhibited effects greater than the toxicity RMD (0.1 and 9.6% for TST and NOEC, respectively, for effluents and 0 and 9.5%, respectively, for ambient samples). Our results demonstrate that the TST is more likely to identify a toxic sample when effects are fairly substantial (≥ 25% effect in chronic testing and ≥ 20% effect in acute tests) and less likely to identify a sample as toxic when effects are negligible (≤ 10% effect). Furthermore, these results demonstrate that appropriate WET data interpretation benefits from having well-designed test methods with sufficient power to identify significant toxicity or biologically insignificant effects

  13. Protein expression analysis of rat testes induced testicular toxicity with several reproductive toxicants.

    PubMed

    Yamamoto, Toshinori; Fukushima, Tamio; Kikkawa, Rie; Yamada, Hiroshi; Horii, Ikuo

    2005-05-01

    The utilization of safety biomarkers to predict the possibility of compound-related toxicity provides several advantages for drug discovery and development, especially at an early stage. The objectives of this study were to investigate the effects of male reproductive toxicants on protein expression profiles in the rat testes and to identify potential biomarker candidates. Four well-known reproductive toxicants, ethylene glycol monomethyl ether (EGME), cyclophosphamide (CP), sulfasalazine (SASP) and 2,5-hexanedione (2,5-HD), were administered to male rats in a single dose, and protein expression profiles were investigated after 24 hr by two-dimensional gel electrophoresis (2DE). Histopathological examination of the testes and serum concentration analysis were also performed. From the results of the comparison of 2D-gels among different doses of a compound and among compounds, 52, 20, 24 and 111 spots were nominated as differentially expressed spots with EGME, CP, SASP and 2,5-HD treatments, respectively. Several spermatogenesis-involved proteins were identified, including glutathione S-transferase (GST), testis-specific heat shock protein 70-2 (HSP70-2), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and phosphatidylethanolamine-binding protein (PEBP). Some of them were altered by more than one compound. In summary, remarkable histopathological findings were observed only in the EGME high-dose group, and most of the protein changes were detected before histopathological changes occurred. Therefore, the proteins identified in this study could potentially serve as biomarkers to evaluate male reproductive toxicity at an early stage of drug discovery and development. PMID:15928459

  14. 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. PMID:22351617

  15. 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...

  16. 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.

  17. 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...

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

    EPA Science Inventory

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

  19. A critical evaluation of the fish early-life stage toxicity test for engineered nanomaterials: experimental modifications and recommendations.

    PubMed

    Shaw, Benjamin J; Liddle, Corin C; Windeatt, Kirsten M; Handy, Richard D

    2016-09-01

    There are concerns that regulatory toxicity tests are not fit for purpose for engineered nanomaterials (ENMs) or need modifications. The aim of the current study was to evaluate the OECD 210 fish, early-life stage toxicity test for use with TiO2 ENMs, Ag ENMs, and MWCNT. Both TiO2 ENMS (≤160 mg l(-1)) and MWCNT (≤10 mg l(-1)) showed limited acute toxicity, whilst Ag ENMs were acutely toxic to zebrafish, though less so than AgNO3 (6-day LC50 values of 58.6 and 5.0 µg l(-1), respectively). Evidence of delayed hatching, decreased body length and increased muscle width in the tail was seen in fish exposed to Ag ENMs. Oedema (swollen yolk sacs) was also seen in fish from both Ag treatments with, for example, mean yolk sac volumes of 17, 35 and 39 µm(3) for the control, 100 µg l(-1) Ag ENMs and 5 µg l(-1) AgNO3 treatments, respectively. Among the problems with the standard test guidelines was the inability to maintain the test solutions within ±20 % of nominal concentrations. Pronounced settling of the ENMs in some beakers also made it clear the fish were not being exposed to nominal concentrations. To overcome this, the exposure apparatus was modified with the addition of an exposure chamber that ensured mixing without damaging the delicate embryos/larvae. This allowed more homogeneous ENM exposures, signified by improved measured concentrations in the beakers (up to 85.7 and 88.1 % of the nominal concentrations from 10 mg l(-1) TiO2 and 50 µg l(-1) Ag ENM exposures, respectively) and reduced variance between measurements compared to the original method. The recommendations include: that the test is conducted using exposure chambers, the use of quantitative measurements for assessing hatching and morphometrics, and where there is increased sensitivity of larvae over embryos to conduct a shorter, larvae-only toxicity test with the ENMs. PMID:27318802

  20. An in vivo evaluation of acute toxicity of cobalt ferrite (CoFe2O4) nanoparticles in larval-embryo Zebrafish (Danio rerio).

    PubMed

    Ahmad, Farooq; Liu, Xiaoyi; Zhou, Ying; Yao, Hongzhou

    2015-09-01

    The broad spectrum applications of CoFe2O4 NPs have attracted much interest in medicine, environment and industry, resulting in exceedingly higher exposures to humans and environmental systems in succeeding days. Their health effects and potential biological impacts need to be determined for risk assessment. Zebrafish (Danio rerio) embryos were exposed to environmentally relevant doses of nano-CoFe2O4 (mean diameter of 40nm) with a concentration range of 10-500μM for 96h. Acute toxic end points were evaluated by survival rate, malformation, hatching delay, heart dysfunction and tail flexure of larvae. Dose and time dependent developmental toxicity with severe cardiac edema, down regulation of metabolism, hatching delay and tail/spinal cord flexure and apoptosis was observed. The biochemical changes were evaluated by ROS, Catalase (CAT), Lipid peroxidation (LPO), Acid phophatase (AP) and Glutatione s- transferase (GST). An Agglomeration of NPs and dissolution of ions induces severe mechanical damage to membranes and oxidative stress. Severe apoptosis of cells in the head, heart and tail region with inhibition of catalase confirms ROS induced acute toxicity with increasing concentration. Increased activity of GST and AP at lower concentrations of CoFe2O4 NPs demonstrates the severe oxidative stress. Circular dichroism (CD) spectra indicated the weak interactions of NPs with BSA and slight changes in α-helix structure. In addition, CoFe2O4 NPs at lower concentrations do not show any considerable interference with assay components and analytical instruments. The results are possible elucidation of pathways of toxicity induced by these particles, as well as contributing in defining the protocols for risk assessment of these nanoparticles. PMID:26197244

  1. 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

  2. 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. PMID:21922641

  3. 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.

  4. 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

  5. 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...

  6. Sediment toxicity testing of Lake Orta after liming

    SciTech Connect

    Baudo, R.; Beltrami, M.; Rossi, D.; Gronda, A.; Abdel-Monem, A.M.; Burton, G.A.

    1995-12-31

    Lake Orta has been severely polluted by industrial effluents containing Cu, NH{sub 3}, Cr., Ni, and Zn. Ammonia oxidation caused a pH drop below 4. More than 60 papers have described the adverse chemical and biological changes which occurred in Lake Orta in the past several decades. In 1989, CaCO{sub 3} (10,900 tons) was added to the lake as a remedial action. The treatment was effective, improving water quality and allowing some original plankton, benthic, and fish populations to return. However, Cu and Cr are still present in the top 10 cm of sediment. The toxicity of the sediment was evaluated using multiple assays: Microtox (solid phase and pore water), Brachionus calyciflorus and Thamnocephalus platyurus Toxkits (pore water), seed germination and root elongation (solid phase and pore water). In addition, in situ and laboratory tests were conducted with Hyalella azteca and an indigenous species of Daphnia. Assays responses varied yet showed surficial sediments to be toxic. Toxicity increased with sediment in pre-liming deposition zones. Recovery of the ecosystem is evident, however the contaminated sediments may impede further improvement.

  7. 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. PMID:25748519

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

    PubMed

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

    2010-04-01

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

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 40 CFR 797.1600 - Fish early life stage toxicity test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Fish early life stage toxicity test. 797.1600 Section 797.1600 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ENVIRONMENTAL EFFECTS TESTING GUIDELINES Aquatic Guidelines § 797.1600 Fish early life stage toxicity test....

  15. 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...

  16. 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, D.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.

  17. 76 FR 38169 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-29

    ... FR 22402) (FRL-7312-2), and later amended by a final rule titled ``Revocation of TSCA Section 4... 12, 2006 (71 FR 18650) (FRL-7751-7). Section 4(d) of TSCA (15 U.S.C. 2603(d)) requires EPA to publish... AGENCY Toxic Substances Control Act Chemical Testing; Receipt of Test Data AGENCY:...

  18. Acute toxicity testing of chemicals-Opportunities to avoid redundant testing and use alternative approaches.

    PubMed

    Creton, Stuart; Dewhurst, Ian C; Earl, Lesley K; Gehen, Sean C; Guest, Robert L; Hotchkiss, Jon A; Indans, Ian; Woolhiser, Michael R; Billington, Richard

    2010-01-01

    Assessment of the acute systemic oral, dermal, and inhalation toxicities, skin and eye irritancy, and skin sensitisation potential of chemicals is required under regulatory schemes worldwide. In vivo studies conducted to assess these endpoints can sometimes be associated with substantial adverse effects in the test animals, and their use should always be scientifically justified. It has been argued that while information obtained from such acute tests provides data needed to meet classification and labelling regulations, it is of limited value for hazard and risk assessments. Inconsistent application of in vitro replacements, protocol requirements across regions, and bridging principles also contribute to unnecessary and redundant animal testing. Assessment of data from acute oral and dermal toxicity testing demonstrates that acute dermal testing rarely provides value for hazard assessment purposes when an acute oral study has been conducted. Options to waive requirements for acute oral and inhalation toxicity testing should be employed to avoid unnecessary in vivo studies. In vitro irritation models should receive wider adoption and be used to meet regulatory needs. Global requirements for sensitisation testing need continued harmonisation for both substance and mixture assessments. This paper highlights where alternative approaches or elimination of tests can reduce and refine animal use for acute toxicity requirements. PMID:20144136

  19. 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...

  20. Effects of the Particulate Matter2.5 (PM2.5) on Lipoprotein Metabolism, Uptake and Degradation, and Embryo Toxicity.

    PubMed

    Kim, Jae-Yong; Lee, Eun-Young; Choi, Inho; Kim, Jihoe; Cho, Kyung-Hyun

    2015-12-31

    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

  1. 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

  2. [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. PMID:26489331

  3. 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.

  4. Acute inhalation toxicity testing: considerations of technical and regulatory aspects.

    PubMed

    Pauluhn, J; Bury, D; Föst, U; Gamer, A; Hoernicke, E; Hofmann, T; Kunde, M; Neustadt, T; Schlede, E; Schnierle, H; Wettig, K; Westphal, D

    1996-01-01

    The EU regulatory statute for the acute hazard identification of chemicals requires selection of the two most appropriate routes of administration. Testing employing the oral route is mandatory, whereas selection of the dermal or inhalation route requires expert judgement, i.e. considerations of structural alerts with regard to the inherent acute inhalation toxicity as well as the likelihood of dermal and inhalation exposure, respectively. Currently, testing of chemicals requires acute inhalation exposure of 4-h and 1-h durations according the EU classification and labelling and UN Transport Guidelines, respectively. The analysis made revealed that 1-h exposures appear to add little knowledge in addition to existing 4-h LC50 values and a default value of 4 should be used for conversion of 4-h to 1-h LC50 values, independently of the physical state of the chemical. Therefore, also the unit of concentration of exposure atmospheres should be independent of nominal features of the test substance. Hence, the preferred dose metric is mass (mg/liter air) rather than volume (ppm). Taking into account the overall variability of acute toxicity data the recommendations given are classification into the following groups of 4-h LC50 values: < or = 0.05, > 0.05-0.2, > 0.2-1, > 1-5 and > 5.0 mg/l. No distinction should be made concerning vapours and aerosols with regard to units and conversion factors from 4-h to 1-h LC50 values and the default factor of 4 appears to be most suitable. Further differentiation of classification is not indicated due to technical variability of acute inhalation testing and resolution of the acute bioassay. PMID:9010579

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

    PubMed Central

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

    2015-01-01

    Objectives The widely promising applications of graphene nanomaterials raise considerable concerns regarding their environmental and human health risk assessment. The aim of the current study was to evaluate the toxicity profiling of graphene family nananomaterials (GFNs) in alternative in vitro and in vivo toxicity testing models. Methods The GFNs used in this study are graphene nanoplatelets ([GNPs]–pristine, carboxylate [COOH] and amide [NH2]) and graphene oxides (single layer [SLGO] and few layers [FLGO]). The human bronchial epithelial cells (Beas2B cells) as in vitro system and the nematode Caenorhabditis elegans as in vivo system were used to profile the toxicity response of GFNs. Cytotoxicity assays, colony formation assay for cellular toxicity and reproduction potentiality in C. elegans were used as end points to evaluate the GFNs’ toxicity. Results In general, GNPs exhibited higher toxicity than GOs in Beas2B cells, and among the GNPs the order of toxicity was pristine>NH2>COOH. Although the order of toxicity of the GNPs was maintained in C. elegans reproductive toxicity, but GOs were found to be more toxic in the worms than GNPs. In both systems, SLGO exhibited profoundly greater dose dependency than FLGO. The possible reason of their differential toxicity lay in their distinctive physicochemical characteristics and agglomeration behavior in the exposure media. Conclusions The present study revealed that the toxicity of GFNs is dependent on the graphene nanomaterial’s physical forms, surface functionalizations, number of layers, dose, time of exposure and obviously, on the alternative model systems used for toxicity assessment. PMID:26602558

  6. In vitro pyrogen test for toxic or immunomodulatory drugs.

    PubMed

    Daneshian, Mardas; Guenther, Armin; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

    2006-06-30

    Pyrogenic contaminations of some classes of injectable drugs, e.g. toxic or immunomodulatory as well as false-positive drugs, represent a major risk which cannot yet be excluded due to the limitations of current tests. Here we describe a modification of the In vitro Pyrogen Test termed AWIPT (Adsorb, Wash, In vitro Pyrogen Test), which addresses this problem by introducing a pre-incubation step in which pyrogenic contaminations in the test sample are adsorbed to albumin-coated beads. After rinsing, the beads are incubated with human whole blood and the release of the endogenous pyrogen interleukin-1beta is measured as a marker of pyrogenic activity. Intentional contaminations with lipopolysaccharide were retrieved from the chemotherapeutic agents paclitaxel, cisplatin and liposomal daunorubicin, the antibiotic gentamicin, the antifungal agent liposomal amphotericin B, and the corticosteroid prednisolone at lower dilutions than in the standard in vitro pyrogen test. This represents a promising new approach for the detection of pyrogenic contamination in drugs or in drugs containing interfering additives and should lead to improved safety levels. PMID:16730742

  7. Transcriptional profiling reveals barcode-like toxicogenomic responses in the zebrafish embryo

    PubMed Central

    Yang, Lixin; Kemadjou, Jules R; Zinsmeister, Christian; Bauer, Matthias; Legradi, Jessica; Müller, Ferenc; Pankratz, Michael; Jäkel, Jens; Strähle, Uwe

    2007-01-01

    Background Early life stages are generally most sensitive to toxic effects. Our knowledge on the action of manmade chemicals on the developing vertebrate embryo is, however, rather limited. We addressed the toxicogenomic response of the zebrafish embryo in a systematic manner by asking whether distinct chemicals would induce specific transcriptional profiles. Results We exposed zebrafish embryos to a range of environmental toxicants and measured the changes in gene-expression profiles by hybridizing cDNA to an oligonucleotide microarray. Several hundred genes responded significantly to at least one of the 11 toxicants tested. We obtained specific expression profiles for each of the chemicals and could predict the identity of the toxicant from the expression profiles with high probability. Changes in gene expression were observed at toxicant concentrations that did not cause morphological effects. The toxicogenomic profiles were highly stage specific and we detected tissue-specific gene responses, underscoring the sensitivity of the assay system. Conclusion Our results show that the genome of the zebrafish embryo responds to toxicant exposure in a highly sensitive and specific manner. Our work provides proof-of-principle for the use of the zebrafish embryo as a toxicogenomic model and highlights its potential for systematic, large-scale analysis of the effects of chemicals on the developing vertebrate embryo. PMID:17961207

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

    EPA Science Inventory

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

  9. 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

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

    PubMed

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

    2000-01-01

    In fulfilment of the aims of the European Union Biocidal Directive (Directive 98/8/EC), Technical Guidance Documents are currently being compiled. Part I of these Technical Guidance Documents covers data requirements for active substances and biocidal products. The Three Rs principle has been applied in certain parts of the toxicity and ecotoxicity testing scheme for pesticides, such as testing for acute oral toxicity, skin and eye irritation, skin sensitisation, and dermal absorption. Further recommendations on how to proceed with regard to the continuing replacement, reduction and refinement of animal experiments in this field of regulatory testing are included for consideration. In this context, besides stressing the necessity to validate and accept further alternatives, emphasis is placed on providing the possibility of waiving unnecessary tests and on the continuous evaluation of whether certain tests are needed at all. PMID:25419935

  11. 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).

  12. 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.

  13. 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...

  14. 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...

  15. 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.

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

    EPA Science Inventory

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

  17. 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.

  18. 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

  19. 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. PMID:27165806

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Simple Diagnostic Tests to Detect Toxic Alcohol Intoxications

    PubMed Central

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

    2008-01-01

    Methanol, ethylene glycol, and diethylene glycol intoxications can produce visual disturbances, neurological disturbances, acute renal failure, pulmonary dysfunction, cardiac dysfunction, metabolic acidosis, and death. Metabolic acidosis and an increased serum osmolality are important clues to their diagnosis. The former reflects the organic acids produced by metabolism of the parent alcohol, while the latter is due to accumulation of the offending alcohol. However, neither the clinical nor the laboratory findings are specific for toxic alcohol ingestions. The definitive diagnosis of the alcohol intoxications is commonly based on detection of the alcohol or its metabolites in blood. Early diagnosis is important, because initiation of appropriate treatment can markedly lessen their morbidity and mortality. At present detection of the parent alcohol in body fluids is inferred from its measurement in blood. This measurement is often performed by specialty laboratories using expensive equipment, and a long delay between obtaining the specimen and getting the results is not unusual. In this report, we describe liquid- based tests that detect methanol, ethylene glycol, diethylene glycol, and ethanol in saliva. The tests are sensitive and they have different specificity for each of the alcohols facilitating distinction among them. The relatively high sensitivity and specificity of the tests as a whole will facilitate the rapid diagnosis of each of these alcohol intoxications. PMID:18940722

  5. The Syrian hamster embryo cells transformation assay identifies efficiently nongenotoxic carcinogens, and can contribute to alternative, integrated testing strategies.

    PubMed

    Benigni, Romualdo; Bossa, Cecilia; Tcheremenskaia, Olga; Battistelli, Chiara Laura; Giuliani, Alessandro

    2015-02-01

    The long-term carcinogenesis bioassays have played a central role in protecting human health, but for ethical and practical reasons their use is dramatically diminishing and the genotoxicity short-term tests have taken the pivotal role in the pre-screening of chemical carcinogenicity. However, this strategy cannot detect nongenotoxic carcinogens. Since up to 25% of IARC human carcinogens are recognized to have nongenotoxic mechanisms of action, the risk they pose to human health cannot be disregarded, and it is urgent to fill the gap in the tools for alternative testing. In this paper, we analyze from different perspectives the ability of Cell Transformation Assays to identify nongenotoxic carcinogens, and we conclude that the Syrian hamster embryo cells test is able to identify nongenotoxic carcinogens with 80-90% efficiency, and thus, can play an important role in integrated, alternative testing strategies. PMID:25813724

  6. 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

  7. 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

  8. 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)

  9. 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

  10. 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. PMID:21777036

  11. 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.

  12. 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...

  13. 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...

  14. 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

  15. 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...

  16. Methods For Collecting , Culturing And Performing Toxicity Tests With Daphnia ambigua

    SciTech Connect

    Specht, Winona L.

    2005-07-01

    Toxicity tests conducted on water collected from impacted locations in SRS streams often failed chronic toxicity tests and sometimes failed acute toxicity tests (Specht 1995). These findings prompted SRS to determine the cause of the failures. Some SRS NPDES outfalls were also failing chronic toxicity tests, even though no toxicant could be identified and when TIEs were performed, none of the TIE treatments removed the toxicity. Ultimately, it was determined that the failures were due to the low hardness of SRS surface waters, rather than to the presence of a toxicant. The species of cladoceran that the EPA recommends for toxicity testing, Ceriodaphnia dubia, is stressed by the very low hardness of SRS waters. SRS developed an alternate species toxicity test that is similar to the EPA test, but uses an indigenous cladoceran, Daphnia ambigua (Specht and Harmon, 1997; Harmon et al., 2003). In 2001, SCDHEC approved the use of D. ambigua for toxicity testing at SRS, contingent upon approval by EPA Region 4. In 2002, EPA Region 4 approved the use of this species for compliance toxicity testing at SRS. Ultimately, the use of this species demonstrated that SRS effluents were not toxic, and most toxicity testing requirements were removed from the NPDES permit that was issued in December 2003, with the exception of one round of chronic definitive testing on outfalls A-01, A-11, and G-10 just before the next NPDES permit application is submitted to SCDHEC. Although the alternate species test was developed at SRS (1996-1998), the culture was transferred to a contract toxicity testing lab (ETT Environmental) located in Greer, SC in 1998. ETT Environmental became certified by SCDHEC to perform toxicity tests using D. ambigua in 2002, and at this time is the only laboratory certified by SCDHEC to perform tests with this species. Because of the expense associated with maintaining the D. ambigua culture for several years when no toxicity testing is required, SRS decided to suspend

  17. 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

  18. SEED GERMINATION AND ROOT ELONGATION TOXICITY TESTS IN HAZARDOUS WASTE SITE EVALUATION: METHODS DEVELOPMENT AND APPLICATIONS

    EPA Science Inventory

    Seed germination tests measure soil toxicity directly, while root elongation tests consider the indirect effects of water-soluble constituents which may be present in site-samples. n the seed germination toxicity test, site-soil is mixed with a reference soil to yield exposure co...

  19. UTILITY OF TOXICITY TESTS TO MEASURE EFFECTS OF SUBSTANCES ON MARINE ORGANISMS

    EPA Science Inventory

    Toxicity tests using single species, microcosms, and communities of test species are described for laboratory evaluations of marine (estuarine and oceanic) pollution effects. The design of acute, early life-stage, life-cycle, and community toxicity tests is discussed. Uses of tes...

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

    EPA Science Inventory

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

  1. [Acute toxicity testing (LD50) of Chinese mineral drugs].

    PubMed

    Yue, W; Liu, W H; Wang, L F; Fu, S X; Li, Y S; Kong, Z K; Tang, Z X; Chen, Z L

    1989-02-01

    Acute toxicity and LD50 of 62 mineral drugs were determined by ig, ip or iv in mice, in order to provide some guidelines for safety in clinical use, as well as for pharmacological and toxicological studies. In the present investigation, the difference in the acute toxicity and LD50 between raw drugs and medicines prepared by roasting is explained. PMID:2506896

  2. 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.

  3. 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

  4. Wheat seed embryo excision enables the creation of axenic seedlings and Koch's postulates testing of putative bacterial endophytes.

    PubMed

    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

  5. 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.

  6. 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.

  7. 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

  8. 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. PMID:27155068

  9. 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)

  10. TERATOGENICITY OF CYCLOPHOSPHAMIDE IN A COUPLED MICROSOMAL ACTIVATING/EMBRYO CULTURE SYSTEM

    EPA Science Inventory

    Using the coupled microsomal activating/embryo culture system, in vitro experiments were performed to establish the role of metabolism in the embryo toxicity and teratogenicity of cyclophosphamide. Cyclophosphamide in the coupled microsomal activating/embryo culture system produc...

  11. 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

  12. 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...

  13. 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.

  14. 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.

  15. 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

  16. 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 ...

  17. 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....

  18. 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 ...

  19. 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.

  20. 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.

  1. 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.

  2. 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...

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

    EPA Science Inventory

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

  4. 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...

  5. [The importance of using biological test objects in studying the toxicity of surface-active substances].

    PubMed

    Mudryĭ, I V; Debrivnaia, I E

    1996-01-01

    The Azotobacter agilis [correction of azobacter agile] culture appeared to be the most sensitive one among the studied test objects. Buckwheat as a test plant can be recommended in studying the toxicity of surface-active substances. PMID:9035856

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

    EPA Science Inventory

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

  7. Abamectin induces rapid and reversible hypoactivity within early zebrafish embryos.

    PubMed

    Raftery, Tara D; Volz, David C

    2015-01-01

    During early zebrafish embryogenesis, spontaneous tail contractions represent the first sign of locomotion and result from innervation of primary motoneuron axons to target axial muscles. Based on a high-content screen, we previously demonstrated that exposure of zebrafish embryos to abamectin--an avermectin insecticide--from 5-25 hours post-fertilization (hpf) abolished spontaneous activity in the absence of effects on survival and gross morphology. Therefore, the objective of this study was to begin investigating the mechanism of abamectin-induced hypoactivity in zebrafish. Similar to 384-well plates, static exposure of embryos to abamectin from 5-25 hpf in glass beakers resulted in elimination of activity at low micromolar concentrations. However, abamectin did not affect neurite outgrowth from spinal motoneurons and, compared with exposure from 5-25 hpf, embryos were equally susceptible to abamectin-induced hypoactivity when exposures were initiated at 10 and 23 hpf. Moreover, immersion of abamectin-exposed embryos in clean water resulted in complete recovery of spontaneous activity relative to vehicle controls, suggesting that abamectin reversibly activated ligand-gated chloride channels and inhibited neurotransmission. To test this hypothesis, we pretreated embryos to vehicle or non-toxic concentrations of fipronil or endosulfan--two insecticides that antagonize the γ-aminobutyric acid (GABA) receptor--from 5-23 hpf, and then exposed embryos to vehicle or abamectin from 23-25 hpf. Interestingly, activity levels within abamectin-exposed embryos pretreated with either antagonist were similar to embryos exposed to vehicle alone. Using quantitative PCR and phylogenetic analyses, we then confirmed the presence of GABA receptor α1 and β2 subunits at 5, 10, and 23 hpf, and demonstrated that zebrafish GABA receptor subunits are homologous to mammalian GABA receptor subunits. Overall, our data collectively suggest that abamectin induces rapid and reversible

  8. 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

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

    NASA Astrophysics Data System (ADS)

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

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

  10. [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. PMID:25693412

  11. Assessment of ammonia toxicity in tests with the microalga, Nephroselmis pyriformis, Chlorophyta.

    PubMed

    Källqvist, T; Svenson, A

    2003-02-01

    Previous studies of an industrial effluent have indicated toxic effects by the ammonium/water system in tests with the unicellular green alga, Nephroselmis pyriformis. This investigation was undertaken to determine the toxicity of ammonia to this alga, and to identify the dominant toxicant in an industrial process effluent. The algal standard test was modified to improve the pH control, i.e. by testing at shorter exposure time and in the presence of a buffering agent, 3 mM HEPES. Ammonia was found to be the predominant toxic form in the dissociating ammonium/water system and the specific toxicity of ammonia (EC50, 24 h exposure) was 2.34 microM (32.8 microg ammonia nitrogen/L). Due to the dissociation, the toxicity is strongly pH dependent. Joint toxicity with additive effects of ammonia and ammonium ions was indicated, but the toxicity of ammonium ions was almost a factor 100 less (EC50, 24 h exposure, 224 microM or 3140 microg ammonium-nitrogen/L). According to the results the EC50 for effect on growth rate of N. pyriformis in seawater of pH 8.0 is 71 microM total ammonium. Hence, this alga appears to be more sensitive to ammonia than other studied marine plankton algae. Ammonia was found to be the dominant toxicant in the industrial effluent, using N. pyriformis as test organism. PMID:12688681

  12. Evaluation of whole effluent toxicity data characteristics and use of Welch's T-test in the test of significant toxicity analysis.

    PubMed

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

    2013-02-01

    The U.S. Environmental Protection Agency (U.S. EPA) and state agencies evaluate the toxicity of effluent and surface water samples based on statistical endpoints derived from multiconcentration tests (e.g., no observed effect concentration, EC25). The test of significant toxicity (TST) analysis is a two-sample comparison test that uses Welch's t test to compare organism responses in a sample (effluent or surface water) with responses in a control or site sample. In general, any form of t test (Welch's t included) is appropriate only if the data meet assumptions of normality and homogeneous variances. Otherwise, nonparametric tests are recommended. TST was designed to use Welch's t as the statistical test for all whole effluent toxicity (WET) test data. The authors evaluated the suitability of using Welch's t test for analyzing two-sample toxicity (WET) data, and within the TST approach, by examining the distribution and variances of data from over 2,000 WET tests and by conducting multiple simulations of WET test data. Simulated data were generated having variances and nonnormal distributions similar to observed WET test data for control and the effluent treatment groups. The authors demonstrate that (1) moderately unequal variances (similar to WET data) have little effect on coverage of the t test or Welch t test (for normally distributed data), and (2) for nonnormally distributed data (similar in distribution to WET data) TST, using Welch's t test, has close to nominal coverage on the basis of simulations with up to a ninefold difference in variance between the effluent and control groups (∼95th percentile based on observed WET test data). PMID:23172744

  13. 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.

  14. 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...

  15. 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.

  16. 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.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and Structural... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11...

  17. 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.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and Structural... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11...

  18. 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. PMID:24889496

  19. 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)

  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. 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.

  2. Abcb4 acts as multixenobiotic transporter and active barrier against chemical uptake in zebrafish (Danio rerio) embryos

    PubMed Central

    2013-01-01

    Background In mammals, ABCB1 constitutes a cellular “first line of defense” against a wide array of chemicals and drugs conferring cellular multidrug or multixenobiotic resistance (MDR/MXR). We tested the hypothesis that an ABCB1 ortholog serves as protection for the sensitive developmental processes in zebrafish embryos against adverse compounds dissolved in the water. Results Indication for ABCB1-type efflux counteracting the accumulation of chemicals in zebrafish embryos comes from experiments with fluorescent and toxic transporter substrates and inhibitors. With inhibitors present, levels of fluorescent dyes in embryo tissue and sensitivity of embryos to toxic substrates were generally elevated. We verified two predicted sequences from zebrafish, previously annotated as abcb1, by cloning; our synteny analyses, however, identified them as abcb4 and abcb5, respectively. The abcb1 gene is absent in the zebrafish genome and we explored whether instead Abcb4 and/or Abcb5 show toxicant defense properties. Quantitative real-time polymerase chain reaction (qPCR) analyses showed the presence of transcripts of both genes throughout the first 48 hours of zebrafish development. Similar to transporter inhibitors, morpholino knock-down of Abcb4 increased accumulation of fluorescent substrates in embryo tissue and sensitivity of embryos toward toxic compounds. In contrast, morpholino knock-down of Abcb5 did not exert this effect. ATPase assays with recombinant protein obtained with the baculovirus expression system confirmed that dye and toxic compounds act as substrates of zebrafish Abcb4 and inhibitors block its function. The compounds tested comprised model substrates of human ABCB1, namely the fluorescent dyes rhodamine B and calcein-am and the toxic compounds vinblastine, vincristine and doxorubicin; cyclosporin A, PSC833, MK571 and verapamil were applied as inhibitors. Additionally, tests were performed with ecotoxicologically relevant compounds: phenanthrene (a

  3. 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. PMID:25461900

  4. 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.

  5. [Subchronic toxicity testing of mold-ripened cheese].

    PubMed

    Schoch, U; Lüthy, J; Schlatter, C

    1984-08-01

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

  6. Preclinical testing for teratogenicity and developmental toxicity: methods and limitations.

    PubMed

    Barrow, P C

    2002-01-01

    With regard to the risk of reproductive or developmental toxicity, the regulatory decisions to allow clinical trials in humans or the marketing of a new drug are based almost entirely on animal data. This is not the case for other types of toxicity for which the preclinical data are supported by data from clinical trials. Whilst animal studies have been remarkably successful in the detection of reproductive toxicology over the last 40 years, they are not infallible. The efficacy of animal experimentation is largely dependent on the selection of appropriate animal models. Progress in the study of teratogenic mechanisms, comparative physiology, developmental biology and pharmacokinetics will hopefully continue to bring about more economical and effective uses of animals. Nevertheless, owing to the limitations of animal models, the monitoring of human births unfortunately remains an essential defence in the detection and early prevention of chemical-induced birth defects. PMID:12185956

  7. 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

  8. 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.

  9. 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

  10. DEVELOPMENT OF PROTOCOLS FOR CHRONIC TOXICITY TESTING OF PACIFIC MARINE SPECIES

    EPA Science Inventory

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

  11. DEVELOPMENT OF A TOXICITY TEST SYSTEM USING PRIMARY RAT LIVER CELLS

    EPA Science Inventory

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

  12. TOXICITY REDUCTION TEST TO ASSIST IN PREDICTING LAND TREATABILITY OF HAZARDOUS ORGANIC WASTES

    EPA Science Inventory

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

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

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

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... in the product. Each lot of antiserum shall be demonstrated by virus neutralization tests not to inhibit other viruses known to be possible contaminants. (c) After neutralization, 0.2 ml of the...

  2. 9 CFR 113.37 - Detection of pathogens by the chicken embryo inoculation test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... in the product. Each lot of antiserum shall be demonstrated by virus neutralization tests not to inhibit other viruses known to be possible contaminants. (c) After neutralization, 0.2 ml of the...

  3. 9 CFR 113.37 - Detection of pathogens by the chicken embryo inoculation test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... in the product. Each lot of antiserum shall be demonstrated by virus neutralization tests not to inhibit other viruses known to be possible contaminants. (c) After neutralization, 0.2 ml of the...

  4. 9 CFR 113.37 - Detection of pathogens by the chicken embryo inoculation test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... in the product. Each lot of antiserum shall be demonstrated by virus neutralization tests not to inhibit other viruses known to be possible contaminants. (c) After neutralization, 0.2 ml of the...

  5. 9 CFR 113.37 - Detection of pathogens by the chicken embryo inoculation test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... in the product. Each lot of antiserum shall be demonstrated by virus neutralization tests not to inhibit other viruses known to be possible contaminants. (c) After neutralization, 0.2 ml of the...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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}.

  11. 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.

  12. TOXICITY TESTS OF EFFLUENTS WITH MARSH PLANTS IN WATER AND SEDIMENT

    EPA Science Inventory

    Methods are described for toxicity testing of water and sediment with the rooted marsh plants, Echinochloa crusgalli var. crusgalli and var. zelavensis (freshwater) and Spartina alterniflora (estuarine). ive industrial effluents, a sewage treatment plant effluent and a herbicide ...

  13. Evaluation of an alternative in vitro test battery for detecting reproductive toxicants.

    PubMed

    Piersma, A H; Bosgra, S; van Duursen, M B M; Hermsen, S A B; Jonker, L R A; Kroese, E D; van der Linden, S C; Man, H; Roelofs, M J E; Schulpen, S H W; Schwarz, M; Uibel, F; van Vugt-Lussenburg, B M A; Westerhout, J; Wolterbeek, A P M; van der Burg, B

    2013-07-01

    The application of alternative methods in developmental and reproductive toxicology is challenging in view of the complexity of mechanisms involved. A battery of complementary test systems may provide a better prediction of developmental and reproductive toxicity than single assays. We tested twelve compounds with varying mechanisms of toxic action in an assay battery including 24 CALUX transcriptional activation assays, mouse cardiac embryonic stem cell test, ReProGlo assay, zebrafish embryotoxicity assay, and two CYP17 and two CYP19 activity assays. The battery correctly detected 11/12 compounds tested, with one false negative occurring, which could be explained by the absence of the specific mechanism of action of this compound in the battery. Toxicokinetic modeling revealed that toxic concentrations were in the range expected from in vivo reproductive toxicity data. This study illustrates added value of combining assays that contain complementary biological processes and mechanisms, increasing predictive value of the battery over individual assays. PMID:23511061

  14. USE OF MARSH PLANTS FOR TOXICITY TESTING OF WATER AND SEDIMENT

    EPA Science Inventory

    The freshwater wetland plants, Echinochlo crusgalli crusgalli andEchinocloa crusgalli zelayensis, and the saltmarsh plant, Spartina alterniflora, were exposed to the herbicides, metolachlor and norflurazon, in two types of toxicity tests: eed germination and early seedling growth...

  15. 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 ...

  16. 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 ...

  17. 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.

  18. 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...

  19. The use of phytotoxicity tests (common duckweed, cabbage, and millet) for determining effluent toxicity.

    PubMed

    Wang, W; Williams, J M

    1990-01-01

    The objective of this study was to use higher plants for detecting effluent toxicity. Eight effluent samples were obtained from three industrial sources prior to their entry into a sewer system. The tests were the duckweed reproduction test, and root growth tests using cabbage and millet. The results of repeated phytotoxicity tests were reproducible. Of the three industrial sources, the effluent samples from a specialty chemical industry were the most toxic. For two samples from this source, the IC50 values (the concentrations which caused 50% inhibitory effect) for duckweed were less than 1.6% effluent concentration. The samples from an agricultural product utilization plant were the least toxic. For these samples, root growth tests failed to obtain IC50 values while the duckweed tests showed IC50 values of 91 and 43% effluent concentration. Among the three types of tests conducted, the duckweed reproduction test showed the greatest sensitivity to effluent toxicity, while root growth tests using cabbage and millet had mixed results. Duckweed is recommended as a part of a battery of tests for effluent toxicity. PMID:24243256

  20. Intra- and interlaboratory variability in acute toxicity tests with glochidia and juveniles of freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Wang, N.; Augspurger, T.; Barnhart, M.C.; Bidwell, Joseph R.; Cope, W.G.; Dwyer, F.J.; Geis, S.; Greer, I.E.; Ingersoll, C.G.; Kane, C.M.; May, T.W.; Neves, R.J.; Newton, T.J.; Roberts, A.D.; Whites, D.W.

    2007-01-01

    The present study evaluated the performance and variability in acute toxicity tests with glochidia and newly transformed juvenile mussels using the standard methods outlined in American Society for Testing and Materials (ASTM). Multiple 48-h toxicity tests with glochidia and 96-h tests with juvenile mussels were conducted within a single laboratory and among five laboratories. All tests met the test acceptability requirements (e.g., ???90% control survival). Intralaboratory tests were conducted over two consecutive mussel-spawning seasons with mucket (Actinonaias ligamentina) or fatmucket (Lampsilis siliquoidea) using copper, ammonia, or chlorine as a toxicant. For the glochidia of both species, the variability of intralaboratory median effective concentrations (EC50s) for the three toxicants, expressed as the coefficient of variation (CV), ranged from 14 to 27% in 24-h exposures and from 13 to 36% in 48-h exposures. The intralaboratory CV of copper EC50s for juvenile fatmucket was 24% in 48-h exposures and 13% in 96-h exposures. Interlaboratory tests were conducted with fatmucket glochidia and juveniles by five laboratories using copper as a toxicant. The interlaboratory CV of copper EC50s for glochidia was 13% in 24-h exposures and 24% in 48-h exposures, and the interlaboratory CV for juveniles was 22% in 48-h exposures and 42% in 96-h exposures. The high completion success and the overall low variability in test results indicate that the test methods have acceptable precision and can be performed routinely. ?? 2007 SETAC.

  1. Validation of a short-term toxicity test endpoint by comparison with longer-term effects on larval red abalone Haliotis rufescens

    SciTech Connect

    Conroy, P.T.; Hunt, J.W.; Anderson, B.S.

    1996-07-01

    Experiments were conducted to compare a short-term 48-h aquatic toxicity test endpoint of abnormal larval shell development with other, more clearly adverse effects. In similar experiments conducted with two different toxicants, zinc sulfate and bleached-kraft mill effluent, red abalone (Haliotis rufescens) embryos were simultaneously exposed to identical dilution series and incubated for three different exposure periods: 48 h, 48 h followed by an 8-d recovery period in clean seawater, and 10 d of continuous exposure. Abnormal larval shell development was assessed in the 48-h short-term tests, and inhibition of metamorphosis was assessed in the exposure-recovery and continuous exposure experiments. For the zinc experiments, the median effective concentration (EC50) values for the 48-h exposure, the exposure-recovery experiment, and the continuous exposure experiment were 40, 34, and 32 {micro}g/L zinc, respectively. For the bleached-kraft mill effluent experiments, the EC50 values were 0.98, 0.76, and 0.69% effluent, respectively. Results indicate that toxicant concentrations causing abnormal larval shell development also inhibit metamorphosis and that larvae exposed to toxicant concentrations which inhibit larval shell development do not recover to metamorphose when transferred to clean seawater. None of the successfully metamorphosed postlarvae had deformed larval shells, indicating that shell deformity precludes survival past the planktonic stage. A longer (15-d) experiment allowed measurement of postlarval shell length in exposed postmetamorphic abalone. Insignificant differences in postlarval shell length indicated that the timing of larval metamorphosis was similar regardless of toxicant exposure and that the effects of the toxicant was to inhibit rather than to delay metamorphosis.

  2. Toxicity evaluation with Vibrio fischeri test of organic chemicals used in aquaculture.

    PubMed

    Hernando, M D; De Vettori, S; Martínez Bueno, M J; Fernández-Alba, A R

    2007-06-01

    The evaluation of acute toxicity by Vibrio fischeri test for different organic chemicals (antibiotics, pesticides, therapeutants, herbicides) commonly applied in aquaculture and a degradation product of surfactants, 4-nonylphenol, is presented in this work. Simazine, atrazine, emamectin benzoate and leucomalachite green have no toxic effects on V. fischeri at the concentration tested (up to 6mgl(-1)) which correspond to the maximum water solubility. Ciprofloxacin, terbutryn and deltamethrin, caused inhibition effects of 28%, 22% and 30% at concentrations up to 5mgl(-1). Toxic effects were not observed in the case of flumequine and oxolinic acid at the maximum concentration tested (0.189mgl(-1)). According to the toxicity categories established in the EU legislation, ciprofloxacin, terbutryn and deltamethrin could be considered non-harmful for V. fischeri. Malachite green and 4-nonylphenol are "very toxic to aquatic organisms" (EC(50,30min)=0.031mgl(-1) and 0.48mgl(-1), respectively). Carbaryl is "toxic to aquatic organisms" (2.4mgl(-1)). and glyphosate is harmful to V. fischeri (EC(50,30min)=44.2mgl(-1)). The matrix effect was evaluated comparing the toxicity measurements of the target compounds solubilized in seawater and distilled water. Malachite green, 4-nonylphenol and glyphosate, showed higher toxicity in distilled water than in seawater. Carbaryl was more toxic in seawater. All the compounds tested in seawater were not harmful at concentrations of ngl(-1) (10 and 50). However, 4-nonlylphenol and malachite green may act as toxic compounds in the environment at a low ppb level, since both may be detected in water at this concentration level. PMID:17292447

  3. Applicability of ambient toxicity testing to national or regional water-quality assessment

    USGS Publications Warehouse

    Elder, J.F.

    1989-01-01

    Comprehensive assessment of the quality of natural waters requires a multifaceted approach. 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 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. A wide variety of toxicity test methods have been developed to fulfill the needs of diverse applications. The methods differ primarily in the full selections made relative to four characteristics: (1) test species, (2) endpoints (acute or chronic), (3) test enclosure type, and (4) test substance (toxicant) that functions as the environmental stress. Toxicity test approachs vary in their capacity to meet the needs of large-scale assessments of existing water quality. Ambient testing is more likely to meet these needs than are the procedures that call for exposure of the test organisms to known concentrations of a single toxicant. However, meaningful interpretation of ambient test results depend on the existence of accompanying chemical analysis of the ambient media. The ambient test substance may be water or sediments. Sediment tests have had limited application, but they are useful because of the fact that most toxicants tend to accumulate in sediments, and many test species either inhabit the sediments or are in frequent contact with them. Biochemical testing methods, which have been developing rapidly in recent years, are likely to be among the most useful procedures for large-scale water quality assessments. They are relatively rapid and simple, and more importantly, they focus on biochemical changes that are the initial responses of virtually all organisms to environmental stimuli. Most species are sensitive to relatively few toxicants and their sensitivities vary as

  4. Development and testing of a low toxicity acid corrosion inhibitor for industrial cleaning applications

    SciTech Connect

    Frenier, W.W.

    1997-02-01

    A low toxicity corrosion inhibitor used in hydrochloric acid cleaning formulations has been developed. This formulation does not contain formaldehyde. It contains cinnamaldehyde, quaternary nitrogen salts, and a nonionic surfactant, none of which are currently known or suspected to be carcinogens. In laboratory tests, corrosion protection values were equivalent to those provided by current commercial acid inhibitors. Field tests using the low toxicity inhibitor were conducted.

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

    PubMed

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

    2016-02-01

    In the wake of the Deepwater Horizon incident (2010) in the Gulf of Mexico, an abundance of research studies have been performed, but the methodologies used have varied making comparisons and replication difficult. In this study, acute toxicity tests with mysids and inland silversides were performed to examine the effect of different variables on test results. The toxicity test variables evaluated in this study included (1) open versus closed static test chambers, (2) natural versus artificial diluent, (3) aerated versus nonaerated test solution, and (4) low versus medium energy water-accommodated (WAF) mixing energies. The use of tests using natural or artificial diluent showed no difference in either toxicity test or analytical chemistry results. Based on median lethal concentrations (LC50) of WAFs of unweathered oil (MASS), mysid tests performed in closed chambers were approximately 41 % lower than LC50 values from open-chamber studies, possibly a result of the presence of low-molecular weight volatile aromatics (i.e., naphthalenes). This research also showed that using a medium-energy WAF (with a 20–25 % vortex) increases the number of chemical components compared with low-energy WAF, thus affecting the composition of the exposure media and increasing toxicity. The comparison of toxic units as a measure of the potential toxicity of fresh and weathered oils showed that weathered oils (e.g., Juniper, CTC) are less toxic than the unweathered MASS oil. In the event of future oil spills, these variables should be considered to ensure that data regarding the potential toxicity and environmental risk are of good quality and reproducible. PMID:26467150

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

    EPA Science Inventory

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

  7. 76 FR 38170 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-29

    ... issue of March 16, 2006 (71 FR 13708) (FRL-7335-2). Section 4(d) of TSCA (15 U.S.C. 2603(d)) requires... Toxicity to Fish. 9. Acute Toxicity to Aquatic Invertebrates. 10. Toxicity to Aquatic Plants, e.g.,...

  8. Genotoxicity and toxicity evaluations of ECF cellulose bleaching effluents using the Allium cepa L. test.

    PubMed

    Roa, O; Yeber, M C; Venegas, W

    2012-08-01

    Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate wastewater quality following an ECF cellulose bleaching process. The results revealed a toxic effect of the effluent, with inhibition of meristem growth and generally lower values of metaphase, anaphase and telophase indices at pH 10.5 than pH 7 for all effluent concentrations. The genotoxicity effect was different from the toxic effect given that the micronucleus and the chromosomal aberration tests in anaphase-telophase cells were low over all ranges of the studied effluent concentrations. PMID:22990817

  9. 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 method for rapidly determining chemical toxicity was evaluated. The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The device, called the Motility Assay Apparatus (MAA) is tested for 30 second determination of chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy, in addition to agreeing for all chemicals with previous manual evaluations of single cell motility.

  10. 40 CFR 797.1950 - Mysid shrimp chronic toxicity test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... use data from these tests in assessing the hazard of a chemical to the aquatic environment. (b...) “Loading” means the ratio of test organism biomass (gram, wet weight) to the volume (liters) of test... the chemical chosen in a geometric series in which the ratio is between 1.5 and 2.0 (e.g., 2, 4, 8,...

  11. Genomic structure, promoter identification, and chromosomal mapping of a mouse nuclear orphan receptor expressed in embryos and adult testes

    SciTech Connect

    Lee, C.H.; Wei, Li-Na; Copeland, N.G.; Gilbert, D.J.; Jenkins, N.A.

    1995-11-01

    We have isolated and characterized overlapping genomic clones containing the complete transcribed region of a newly isolated mouse cDNA encoding an orphan receptor expressed specifically in midgestation embryos and adult testis. This gene spans a distance of more than 50 kb and is organized into 13 exons. The transcription initiation site is located at the 158th nucleotide upstream from the translation initiation codon. All the exon/intron junction sequences follow the GT/AG rule. Based upon Northern blot analysis and the size of the transcribed region of the gene, its transcript was determined to be approximately 2.5 kb. Within approximately 500 hp upstream from the transcription initiation site, several immune response regulatory elements were identified but no TATA box was located. This gene was mapped to the distal region of mouse chromosome 10 and its locus has been designated Tr2-11. Immunohistochemical studies show that the Tr2-11 protein is present mainly in advanced germ cell populations of mature testes and that Tr2-11 gene expression is dramatically decreased in vitamin A-depleted animals. 23 refs., 7 figs.

  12. Evaluation of anticoccidial drugs in chicken embryos.

    PubMed

    Xie, M Q; Fukata, T; Gilbert, J M; McDougald, L R

    1991-01-01

    Infections of Eimeria tenella in chicken embryos were used to compare the anticoccidial activity of ten drugs. The minimal inhibitory concentration (MIC) and minimal toxic concentration (MTC) were affected by the time of inoculation into the embryos and by the chemical nature of the compounds. Some compounds (nicarbazin, amprolium) had no effect on the development of coccidia when they were injected into embryos after the day of infection. Drugs that act early in the life cycle of coccidia (robenidine, clopidol, decoquinate, diclazuril, halofuginone, monensin, salinomycin, and lasalocid) were active at 5-125 micrograms/embryo when they were injected on the day of infection. The ionophores and halofuginone were highly toxic to embryos; most synthetic compounds were nontoxic. The incubation of merozoites in drug suspensions prior to the infection of embryos did not result in embryo toxicity, but the resultant MICs were much higher than those obtained when drugs were injected directly into the embryos. Several products were essentially inactive. Neither nicarbazin nor amprolium prevented oocyst formation. The widely divergent endpoints for the MIC and MTC of anticoccidials in embryos seriously limits the application of this technique as a screen for anticoccidial drugs. PMID:1792230

  13. Toxicity testing of ground water, surface water and waste water in the island of Cyprus

    SciTech Connect

    McNaughton, E.; Kouris, D.; Guden, H.; Gokcekus, H.

    1995-12-31

    The island of Cyprus is an exporter of agricultural products to the European Community (EC). Public health and environmental toxicity testing programs on the island, especially in the Greek-dominated south, are based on EC models. Following EC guidelines, an environmental toxicology laboratory is being established at the State Laboratory in Nicosia. It will test water for toxicity using the acute Daphnia magna survival test, the chronic 4-day algal growth test (Selenastrum capricomutum), Microtox and Mutatox. During a 6-month survey of water and wastewater using the acute Ceriodaphnia dubia test and the algal growth test, the question of the relevance of environmental toxicity testing in an ecosystem devoid of natural year round freshwater sources, excepting ground water, was examined. Municipal wells, potable and agricultural water reservoirs, municipal and industrial effluent were tested. Preliminary studies showed some municipal well water to be toxic to freshwater species, probably due to high salt content. Water from a newly developed reservoir was toxic, probably due to its location at the base of eroding hills recently mined for copper. Effluent from a paper factory was toxic, but the reservoir into which it flows was not, nor was the sulfide-rich water toxic to untreated seeds. For the water-deficient ecosystem of Cyprus, the environmental testing program must be different from those developed for the European continent. The choice of appropriate test species, the need to focus on water quality for public health and agricultural use, and the possible benefits of nutrient-enriched waste water flowing into sterile ocean water, must all be considered.

  14. Use of sublethal endpoints in sediment toxicity testing with the amphipod Hyalella azteca

    SciTech Connect

    Kemble, N.E.; Brunson, E.B.; Dwyer, F.J.; Ehrhardt, E.A.; Hardesty, D.K.; Haverland, P.S.; Ingersoll, C.G.

    1995-12-31

    ASTM and EPA standard methods for sediment toxicity tests with Hyalella azteca typically recommend use of lethality as the endpoint in a 10-d exposure. However, data from 10- to 28-d exposures with amphipods indicate sublethal endpoints (i.e., growth, sexual maturation, or reproduction) identify additional samples as toxic. The authors compared the frequency that lethal and sublethal endpoints identified a sediment sample as toxic in 14- and 28-d amphipod exposures. In the 14-d amphipod exposures, lethality identified 20% of the samples as toxic, and sublethal endpoints identified an additional 16% of the samples as toxic using sublethal endpoints only. Similarly, in the 28-d exposures, lethality identified 14% of the samples as toxic and sublethal endpoints identified an additional 18% of the samples as toxic. The authors are also currently evaluating Sediment Effect Concentrations (SECs) relative to both lethal and sublethal endpoints in H. azteca exposures. These SECs will be used to evaluate reliability in estimating toxicity of samples. Potential factors which may confound interpretation of sublethal endpoints in sediment tests include: (1) changes in sediment chemistry resulting from long-term storage or feeding (2) the influence of physical characteristics of sediment (grain size), and (3) effects of ammonia or hydrogen sulfide.

  15. Relative toxicity testing of spacecraft materials. 2: Aircraft materials

    NASA Technical Reports Server (NTRS)

    Lawrence, W. H.

    1980-01-01

    The relative toxicity of thermodegradation (pyrolysis/combustion) products of aircraft materials was studied. Two approaches were taken to assess the biological activity of the pyrolysis/combustion products of these materials: (1) determine the acute lethality to rats from inhalation of these pyrolysates and (2) examine the tendency for sublethal exposure to the pyrolysates to disrupt behavioral (shock avoidance) performance of exposed rats. The ralative importance of lethality vs. behavioral effects in selection of a material may be dictated by whether or not individuals potentially exposed to such products, would have an opportunity to escape if they were behaviorally capable of doing so. If so, the second parameter would assume greater importance, but if not the first parameter may be of much greater importance in selecting materials.

  16. Toxicity tests of effluents with marsh plants in water and sediment

    SciTech Connect

    Walsh, G.E.; Weber, D.E.; Simon, T.L.; Brashers, L.K.

    1991-01-01

    Methods are described for toxicity testing of water and sediment with two varieties of the freshwater marsh plant Echinochloa crusgalli (Linneaus) Palisot de Beauvois (Poaceae), and complex effluents. Two tests are described: a seed germination and early seedling growth test in water, and a survival and seedling growth test in natural and synthetic sediments. Effects of effluents from a sewage treatment plant, tannery, textile mill, pulp and paper mill, coking plant and sewage treatment plant included inhibition of germination, chlorophyll synthesis and growth. The tests with rooted marsh plants were sensitive to pollutants and detected toxicity of a range of pollutants in water and sediment. Synthetic sediments similar to natural sediments allowed toxicity tests to be done under carefully controlled conditions of particle size distribution, organic content, pH, electrode potential (Eh) and cation exchange capacity (CEC).

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

    SciTech Connect

    Joseph Bidwell; Jonathan Fisher; Naomi Cooper

    2008-03-31

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

  18. Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing

    PubMed Central

    Seidle, Troy; Robinson, Sally; Holmes, Tom; Creton, Stuart; Prieto, Pilar; Scheel, Julia; Chlebus, Magda

    2010-01-01

    Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area. PMID:20484382

  19. Cumulative bioluminescence; A potential rapid test of drilling fluid toxicity: development study

    SciTech Connect

    Stiffey, A.V. )

    1992-03-01

    A new rapid test of drilling fluid toxicity is based on the spontaneous bioluminescence of Pyrocystis lunula, an easy-to-culture alga that vigorously responds to shear stress (mixing) by emitting a sharp burst of light. In contrast to other bioluminescence methods, a cumulative flux of light is measured with a photomultiplier that eliminates the effect of exposure time on test results. Light quenching, caused by the presence of a toxicant, results in the dose/response relationship (DSR) typical for the enzymatic reaction kinetics. The Michaelis-Menten (dissociation) constant is used as a direct measure of toxicity. The evaluation study involved multiple experiments with 60 samples of drilling fluids from the U.S. gulf coast, as well as such typical toxicants as diesel oil, mineral oil, and chrome lignosulfonate (CLS). In this paper, the results of the test error analysis and comparisons with the Microtox and Mysid shrimp assays are reported.

  20. Influence of sediment composition on apparent toxicity in a solid-phase test using bioluminescent bacteria

    SciTech Connect

    Benton, M.J.; Malott, M.L. |; Knight, S.S.; Cooper, C.M.; Benson, W.H.

    1995-03-01

    Clean and spiked sediment formulations of various silt:sand and clay:sand ratios were tested for toxicity using a bioassay that utilizes bioluminescent bacteria. Measured toxicities of clean and copper sulfate-spiked sediments were negatively but nonlinearly related with percent silt and percent clay, but no significant relationship existed between measured toxicity and sediment composition for methyl parathion-spiked formulations. Results suggest that solid-phase sediment bioassays using bioluminescence bacteria may be useful for testing the toxicities of single contaminants in formulated artificial sediments of known particle-size composition, and for repeated samples collected from the same site. However, extreme caution must be taken when testing sediments of varying composition or which may be differentially contaminated or contain a suite of contaminants.

  1. USE OF THE AMPHIPOD CRUSTACEAN HYALELLA AZTECA IN FRESHWATER AND ESTUARINE SEDIMENT TOXICITY TESTS

    EPA Science Inventory

    Hyalella azteca (Saussure), which are currently used in toxicity tests with freshwater sediments, were tested to determine their suitability for tests with estuarine sediments. eproduction was good after 24 d at and below 12.5 g/L (ppt) salinity in water only. C50 values (50% red...

  2. VALIDITY OF EFFLUENT AND AMBIENT TOXICITY TESTS FOR PREDICTING BIOLOGICAL IMPACT, BACK RIVER, BALTIMORE HARBOR, MARYLAND

    EPA Science Inventory

    The purpose for the study was to measure the toxicity of effluents discharged to an estuary using freshwater test species and compare the predictions with the receiving water biological impact. In addition, ambient tests were done in conjunction with salinity tolerance tests to c...