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1

Comparative Evaluation of Three Rapid Marine Toxicity Tests: Sea Urchin Early Embryo Growth Test, Sea Urchin Sperm Cell Toxicity Test and Microtox.  

National Technical Information Service (NTIS)

Three rapid marine toxicity tests were evaluated to determine their potential usefulness in a toxicity testing program: early embryo growth test and sperm cell toxicity test, both using the sea urchin Arbacia punctulata, and Microtox. Toxicity values (EC5...

D. Nacci E. Jackim R. Walsh

1986-01-01

2

Toxicity testing of human assisted reproduction devices using the mouse embryo assay.  

PubMed

Systems to assess the toxicity of materials used in human assisted reproduction currently lack efficiency and/or sufficient discriminatory power. The development of 1-cell CBA/B6 F1 hybrid mouse embryos to blastocysts, expressed as blastocyst rate (BR), is used to measure toxicity. The embryos were divided into control and test groups, and were exposed to either control medium or to a potentially toxic test medium. Inferences on toxicity were based on differences in BR between the two groups. The mouse embryo assay followed a stratified (mouse), randomized (embryo), and balanced (equal number of embryos per group and per mouse) design. The number of embryos needed was calculated using power analysis. The basal BR of the hybrid strain was determined in a historical population. Sixty-nine mouse embryos per group were required to detect toxic materials with sufficient sensitivity and to account for the considerable inter-mouse variation in blastocyst development. Fifty-two samples, divided over batches of seven different products were tested before use in the study IVF centre and five of these were found to be toxic. This test system, presented as the Nijmegen mouse embryo assay (NMEA), can be used to detect embryo-toxic materials in daily IVF practice, and this report may provide a starting point for standardization. PMID:19400995

Punt-van der Zalm, J P E M; Hendriks, J C M; Westphal, J R; Kremer, J A M; Teerenstra, S; Wetzels, A M M

2009-04-01

3

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

Microsoft Academic Search

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

W. S. Fisher; S. S. Foss

1993-01-01

4

Is the fish embryo toxicity test (FET) with the zebrafish (Danio rerio) a potential alternative for the fish acute toxicity test?  

PubMed

The fish acute toxicity test is a mandatory component in the base set of data requirements for ecotoxicity testing. The fish acute toxicity test is not compatible with most current animal welfare legislation because mortality is the primary endpoint and it is often hypothesized that fish suffer distress and perhaps pain. Animal alternative considerations have also been incorporated into new European REACH regulations through strong advocacy for the reduction of testing with live animals. One of the most promising alternative approaches to classical acute fish toxicity testing with live fish is the fish embryo toxicity (FET) test. The FET has been a mandatory component in routine whole effluent testing in Germany since 2005 and has already been standardized at the international level. In order to analyze the applicability of the FET also in chemical testing, a comparative re-evaluation of both fish and fish embryo toxicity data was carried out for a total of 143 substances, and statistical approaches were developed to evaluate the correlation between fish and fish embryo toxicity data. Results confirm that fish embryo tests are neither better nor worse than acute fish toxicity tests and provide strong scientific support for the FET as a surrogate for the acute fish toxicity test. PMID:19095081

Lammer, E; Carr, G J; Wendler, K; Rawlings, J M; Belanger, S E; Braunbeck, Th

2008-12-03

5

Toxicity testing of waterborne mercury with red sea bream (Pagrus major) embryos and larvae.  

PubMed

Acute toxicity tests revealed that, in red sea bream (Pagrus major) embryos, 24 and 48 h LC(50) values of waterborne HgCl(2) were 67.3 and 39.1 ?g Hg(2+) L(-1). In larvae, 48, 72 and 96 h LC(50) values were 41.9, 36.1 and 34.8 ?g Hg(2+) L(-1), respectively. Sub-chronic toxicity tests indicated that mercury concentrations ?20 ?g Hg(2+) L(-1) decreased hatching success, increased mortality and induced teratogenicity in embryos and larvae. The NOEC, LOEC and MATC values were 8.0, 16.3 and 11.4 ?g Hg(2+) L(-1) for hatching success, mortality and teratogenicity; while those were 27.0, 36.9 and 31.6 ?g Hg(2+) L(-1) for body length and specific growth rate, respectively. PMID:21416140

Huang, Wei; Cao, Liang; Shan, Xiujuan; Lin, Longshan; Dou, Shuozeng

2011-03-17

6

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...

7

Characterization of grass shrimp ( Palaemonetes pugio) embryo toxicity tests using the water soluble fraction of number 2 fuel oil  

Microsoft Academic Search

Toxicity test procedures using grass shrimp Palaemonetes pugio exposed to water soluble fraction (WSF) of Number 2 fuel oil were modified to improve test utility and efficiency. The original test procedure, a 12-day embryo exposure period in glass tubes, was compared with modified 4-day and 12-day tests in plastic tissue culture plates. Comparison of LC50 values, coefficients of variation and

James R. Rayburn; Patricia S. Glas; Steve S. Foss; William S. Fisher

1996-01-01

8

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

Microsoft Academic Search

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

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

2010-01-01

9

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

SciTech Connect

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

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

1993-01-01

10

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

PubMed Central

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

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

2011-01-01

11

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 ...

12

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

PubMed

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

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

2011-04-07

13

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

SciTech Connect

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

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

2011-06-01

14

Toxic effects of brominated indoles and phenols on zebrafish embryos.  

PubMed

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

Kammann, U; Vobach, M; Wosniok, W

2006-01-17

15

Toxic and teratogenic silica nanowires in developing vertebrate embryos  

PubMed Central

Silica-based nanomaterials show promise for biomedical applications such as cell-selective drug delivery and bioimaging. They are easily functionalized, which allows for the conjugation or encapsulation of important biomolecules. Although recent in vitro studies suggested that silica-derived nanomaterials are nontoxic, in vivo studies of silica nanomaterial toxicity have not been performed. Using the embryonic zebrafish as a model system, we show that silica nanomaterials with aspect ratios greater than 1 are highly toxic (LD50 = 110 pg/g embryo) and cause embryo deformities, whereas silica nanomaterials with an aspect ratio of 1 are neither toxic nor teratogenic at the same concentrations. Silica nanowires also interfere with neurulation and disrupt expression of sonic hedgehog, which encodes a key midline signaling factor. Our results demonstrate the need for further testing of nanomaterials before they can be used as platforms for drug delivery. From the Clinical Editor: Silica-based nanomaterials show promise for biomedical applications such as cell-selective drug delivery and bioimaging. Using an embryonic zebrafish model system silica nanomaterials with aspect ratios greater than one were found to be highly toxic; whereas silica nanomaterials with an aspect ratio of one are neither toxic nor teratogenic. These results demonstrate the need for testing “nanomaterials” before they can be used as platforms for drug delivery.

Nelson, Steve M.; Mahmoud, Tarek; Beaux, Miles; Shapiro, Pamela; McIlroy, David N.; Stenkamp, Deborah L.

2010-01-01

16

Evaluation of MWNT toxic effects on daphnia and zebrafish embryos  

NASA Astrophysics Data System (ADS)

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.

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

2009-05-01

17

Comparison of testing acute toxicity on embryo of zebrafish, Brachydanio rerio and RTG-2 cytotoxicity as possible alternatives to the acute fish test  

Microsoft Academic Search

The present study compares two possible alternative methods to replace the acute fish test. Fertilized eggs of zebrafish, Brachydanio rerio were used to investigate the acute toxicity of chemicals. Different toxicological endpoints such as coagulation of the eggs, development of gastrulation, number of somites, development of organs, circulation, heartbeat, otolithanlage and pigmentation have been examined during the embryonic development of

Monica Lange; Wolfgang Gebauer; Jürgen Markl; Roland Nagel

1995-01-01

18

Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae  

PubMed Central

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

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

2013-01-01

19

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

Microsoft Academic Search

An invertebrate embryo toxicity test with the ampullariid snail, Marisacornuarietis, to assess the toxicity of pesticides and heavy metals recently was established. Snail embryos were treated with atrazine (100, 1000, 10000, and 30000?g\\/L), imidacloprid (10000, 25000, and 50000?g\\/L), Ni2+ (0.1, 1, 10, and 100?g\\/L) or Zn2+ (100, 200, 500, 1000, 2000, and 5000?g\\/L). The effect of these substances was examined

Banthita Sawasdee; Heinz-R. Köhler

2009-01-01

20

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

NASA Astrophysics Data System (ADS)

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

Yang, Zhihui; Zhang, Xiangjing; Cai, Zhonghua

2009-05-01

21

Toxicity of Organic Compounds to Marine Invertebrate Embryos and Larvae: A Comparison Between the Sea Urchin Embryogenesis Bioassay and Alternative Test Species  

Microsoft Academic Search

This study investigated the toxic effects of the insecticides lindane and chlorpyrifos, the herbicide diuron, the organometallic antifoulant tributyltin (TBT), and the surfactant sodium dodecyl sulfate (SDS) on the early life stages of Paracentrotus lividus (Echinodermata, Euechinoidea), Ciona intestinalis (Chordata, Ascidiacea), Maja squinado and Palaemon serratus (Arthropoda, Crustacea) in laboratory acute toxicity tests. The assays studied embryogenesis success from fertilized

Juan Bellas; Ricardo Beiras; José Carlos Marińo-Balsa; Nuria Fernández

2005-01-01

22

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...

23

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

PubMed Central

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

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

2009-01-01

24

Developmental Toxicity of Methanol in Whole Embryo Culture: A Comparative Study with Mouse and Rat Embryos.  

National Technical Information Service (NTIS)

Methanol (MeOH), a widely used industrial solvent, has been proposed as an alternative motor vehicle fuel. Inhaled MeOH is developmentally toxic in both rats and nice but the mouse is more sensitive than is the rat. The contribution of the embryo to this ...

J. E. Andrews M. Ebron-McCoy T. R. Logsdon L. M. Mole R. J. Kavlock

1993-01-01

25

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...

26

DEVELOPMENTAL TOXICITY TESTING  

EPA Science Inventory

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

27

Teratogenic and Toxic Effects of Alcohol Ethoxylate and Alcohol Ethoxy Sulfate Surfactants on Xenopus laevis Embryos and Tadpoles  

Microsoft Academic Search

The two surfactants tested, an alcohol ethoxylate (AE) and an alcohol ethoxy sulfate (AES), demonstrate both teratogenic and toxic effects in Xenopus laevis embryos and tadpoles. From acute tests and observations of malformations under light and electron microscopy, the AES produced less teratogenic and toxic effects than the AE, from which it differs only by the presence of a sulfate

Pietro Cardellini; Lino Ometto

2001-01-01

28

In Vivo Nanotoxicity Testing using the Zebrafish Embryo Assay  

PubMed Central

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

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

2013-01-01

29

Developmental toxicity evaluation of three hexabromocyclododecane diastereoisomers on zebrafish embryos.  

PubMed

Structural dissimilarities of hexabromocyclododecane diastereoisomers could raise substantial differences in physicochemical, biological and toxicological properties. In order to fully assess the environmental safety and health risk of hexabromocyclododecanes (HBCDs), zebrafish embryos were used to evaluate the developmental toxicity of individual HBCD diastereoisomers (?-HBCD, ?-HBCD and ?-HBCD). Four-hour post-fertilization (hpf) zebrafish embryos were exposed to different concentrations of HBCD diastereoisomers (0, 0.01, 0.1 and 1.0 mg/l) until 120 hpf. The results showed that exposure to HBCDs can affect the development of zebrafish embryos/larvae in a dose-dependent and diastereoselective manner. The diastereoisomers ?-, ?- and ?-HBCD at 0.01 mg/l had little effect on the development of zebrafish embryos except that exposure to 0.01 mg/l ?-HBCD significantly delayed hatching (P<0.05). At 0.1mg/l, ?-HBCD resulted in depressed heart rate of larvae (96 hpf) and delayed hatching, whereas ?- and ?-HBCD both caused significant hatching delay and growth inhibition (P<0.05). In addition, a remarkable and significant increase in mortality and malformation rate was noted at 0.1 mg/l ?-HBCD exposure groups (P<0.05). At 1.0 mg/l, ?-, ?- and ?-HBCD significantly affected all of the endpoints monitored (P<0.05). Additionally, HBCD diastereoisomers could induce the generation of reactive oxygen species (ROS) and the activities of caspase-3 and caspase-9 in a dose-dependent manner. The results indicated that HBCD diastereoisomers could cause developmental toxicity to zebrafish embryos through inducing apoptosis by ROS formation. The overall results showed a good agreement confirming that the order of developmental toxicity of HBCD diastereoisomers in zebrafish is ?-HBCD>?-HBCD>?-HBCD. PMID:22360937

Du, Miaomiao; Zhang, Dandan; Yan, Changzhou; Zhang, Xian

2012-01-26

30

Developmental Toxicity of Dextromethorphan in Zebrafish Embryos/Larvae  

PubMed Central

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

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

2012-01-01

31

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

PubMed

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

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

2012-03-03

32

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

SciTech Connect

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.

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

1993-01-01

33

Molecular mechanisms of toxicity of silver nanoparticles in zebrafish embryos.  

PubMed

Silver nanoparticles cause toxicity in exposed organisms and are an environmental health concern. The mechanisms of silver nanoparticle toxicity, however, remain unclear. We examined the effects of exposure to silver in nano-, bulk-, and ionic forms on zebrafish embryos (Danio rerio) using a Next Generation Sequencing approach in an Illumina platform (High-Throughput SuperSAGE). Significant alterations in gene expression were found for all treatments and many of the gene pathways affected, most notably those associated with oxidative phosphorylation and protein synthesis, overlapped strongly between the three treatments indicating similar mechanisms of toxicity for the three forms of silver studied. Changes in oxidative phosphorylation indicated a down-regulation of this pathway at 24 h of exposure, but with a recovery at 48 h. This finding was consistent with a dose-dependent decrease in oxygen consumption at 24 h, but not at 48 h, following exposure to silver ions. Overall, our data provide support for the hypothesis that the toxicity caused by silver nanoparticles is principally associated with bioavailable silver ions in exposed zebrafish embryos. These findings are important in the evaluation of the risk that silver particles may pose to exposed vertebrate organisms. PMID:23758687

van Aerle, Ronny; Lange, Anke; Moorhouse, Alex; Paszkiewicz, Konrad; Ball, Katie; Johnston, Blair D; de-Bastos, Eliane; Booth, Timothy; Tyler, Charles R; Santos, Eduarda M

2013-06-26

34

Further Development of Rodent Whole Embryo Culture: Solvent Toxicity and Water Insoluble Compound Delivery System.  

National Technical Information Service (NTIS)

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...

K. T. Kitchin M. T. Ebron

1984-01-01

35

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

PubMed

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

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

2013-01-20

36

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

PubMed

An invertebrate embryo toxicity test with the ampullariid snail, Marisacornuarietis, to assess the toxicity of pesticides and heavy metals recently was established. Snail embryos were treated with atrazine (100, 1000, 10000, and 30000 microg/L), imidacloprid (10000, 25000, and 50000 microg/L), Ni(2+) (0.1, 1, 10, and 100 microg/L) or Zn(2+) (100, 200, 500, 1000, 2000, and 5000 microg/L). The effect of these substances was examined by monitoring the following endpoints: mortality, formation of tentacles and eyes, heart rate, hatching, and weight after hatching. Effects in term of a significant delay on the formation of both tentacles and eyes were found after treatment with 100 microg/L Ni(2+) or 200 microg/L Zn(2+). The heart rate was shown to significantly decrease at 25000 microg/L imidacloprid or 1000 microg/L Zn(2+). At 100 microg/L atrazine, 10 microg/L Ni(2+), or 1000 microg/L Zn(2+) a significant delay in hatching became visible. No significant mortality was observed for the tested concentrations of atrazine, imidacloprid, or Ni(2+), while 5000 microg/L Zn(2+) resulted in 100% mortality after 10d. The weight of freshly hatched individuals remained unaffected in all treatments. On the basis of the lowest observed effect concentrations (LOECs) recorded, we could show the M.cornuarietis embryo toxicity test (MariETT) to react up to three orders of magnitude more sensitive (for metals) and at least one order of magnitude more sensitive (for the tested organics) than the established Danio rerio embryo test. PMID:19278713

Sawasdee, Banthita; Köhler, Heinz-R

2009-03-10

37

Developmental toxicity of 3,4-dichloroaniline on rare minnow (Gobiocypris rarus) embryos and larvae.  

PubMed

Gobiocypris rarus is a freshwater cyprinid, which possesses lots of attractive features (short life cycle, high fecundity, and especially the transparent trait during early life stage) that make it a suitable model in aquatic toxicity tests. In this study, the effects of 3,4-dichloroaniline (3,4-DCA) on the early life stages of G. rarus were measured. As endpoints, normal developmental parameters (survival rate, malformation rate, total body length and average heart rate) as well as biomarker genes (stress response (hsp70), organizer function and axis formation (wnt8a), vascular system development (vezf1), detoxification (cyp1a) and endocrine disruption (er?)) in the developing embryos and larvae were recorded during a 72 h exposure. The results revealed that reduced survival rate, increased malformation, changes in heart rate and total body length provide a gradual dose-response relationship, values of 72 h LC(50) were 4.146 (3.665-4.713) mg L(-1) for embryos and 1.088 (0.832-1.432) mg L(-1) for larvae. The developmental biochemical biomarkers are very promising tools to determine the severity of toxicants in the growing G. rarus embryos and larvae, even at a concentration of 1% for LC(50). Gene expressions of wnt8a and cyp1a in embryos were highly up-regulated (more than 100-fold) after exposure to 3,4-DCA. Overall, the present study points out that 3,4-DCA is high toxic to the early development of G. rarus, and offers a practicable and highly sensitive bioassay for the general assessment of chemical toxicity. PMID:23047119

Zhu, Bin; Liu, Tianqiang; Hu, Xuegang; Wang, Gaoxue

2012-10-06

38

The Future of Toxicity Testing  

Microsoft Academic Search

In 2007, the U.S. National Research Council (NRC) released a report, “Toxicity Testing in the 21st Century: A Vision and a Strategy,” that proposes a paradigm shift for toxicity testing of environmental agents. The vision is based on the notion that exposure to environmental agents leads to adverse health outcomes through the perturbation of toxicity pathways that are operative in

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

2010-01-01

39

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

Code of Federal Regulations, 2013 CFR

... false Detection of pathogens by the chicken embryo inoculation test. 113.37...113.37 Detection of pathogens by the chicken embryo inoculation test. The test...each of at least 20 fully susceptible chicken embryos. (1) Twenty embryos,...

2013-01-01

40

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

Code of Federal Regulations, 2010 CFR

... false Detection of pathogens by the chicken embryo inoculation test. 113.37...113.37 Detection of pathogens by the chicken embryo inoculation test. The test...each of at least 20 fully susceptible chicken embryos. (1) Twenty embryos,...

2009-01-01

41

Toxicity and protective efficiency of cryoprotectants to flounder (Paralichthys olivaceus) embryos.  

PubMed

With the purpose of finding an ideal cryoprotectant or combination of cryoprotectants in a suitable concentration for flounder (Paralichthys olivaceus) embryo cryopreservation, we tested the toxicities, at culture temperature (16 degrees C), of five most commonly used cryoprotectants-dimethyl sulfoxide (Me2SO), glycerol, methanol (MeOH), 1,2-propylene glycol (PG) and ethylene glycol (EG). In addition, cryoprotective efficiency to flounder embryos of individual and combined cryoprotectants were tested at -15 degrees C for 60 min. Five different concentrations of each of the five cryoprotectants and 20 different combinations of these cryoprotectants were tested for their protective efficiency. The results showed that the toxicity to flounder embryos of the five cryoprotectants are in the following sequence: PG < MeOH < Me2SO < glycerol < EG (P < 0.05); whereas the protective efficiency of each cryoprotectant, at -15 degrees C for a period of 60 min, are in the following sequence: PG > Me2SO approximately MeOH approximately glycerol > EG (greater symbols mean P < 0.05, and approximate symbols mean P > 0.05). Methanol combined with any one of the other cryoprotectants gave the best protection, while ethylene glycol combined with any one of the other cryoprotectants gave the poorest protection at -15 degrees C. Toxicity effect was concentration dependent with the lowest concentration being the least toxic for all five cryoprotectants at 16 degrees C. For PG, MeOH and glycerol, 20% solutions gave the best protection at -15 degrees C; whereas a 15% solution of Me2SO, and a 10% solution of EG, gave the best protection at -15 degrees C. PMID:15629795

Zhang, Y Z; Zhang, S C; Liu, X Z; Xu, Y J; Hu, J H; Xu, Y Y; Li, J; Chen, S L

2005-02-01

42

Cytogenetic and developmental toxicity of cerium and lanthanum to sea urchin embryos.  

PubMed

The aim of this study was to evaluate the toxicity of two rare earth elements (REE), cerium and lanthanum on sea urchin embryos and sperm. Sea urchin (Paracentrotus lividus) embryos were reared for 72 h in Ce(IV)- or La(III)-contaminated seawater at concentrations ranging from 10(-8) to 10(-5) M. Cleaving embryos (5h post-fertilization) were submitted to cytogenetic analysis, scoring mitotic activity and a set of mitotic aberrations. Embryological analysis was carried out to determine percent developmental anomalies and/or embryonic mortality. P. lividus sperm were suspended in Ce(IV) or La(III) (10(-8)-10(-5)M) for 1h, and percent fertilized eggs were scored in cleaving embryos that were cultured up to pluteus stage to score any developmental defects. Embryos reared in 10(-5)M Ce(IV) resulted in 100% embryonic mortality, whereas 10(-5)M La(III) induced 100% developmental defects, without causing any embryonic mortality. A significant concentration-related mitotoxic effect and induction of mitotic aberrations were observed in Ce(IV)-exposed, but not in La(III)-exposed embryos, at concentrations ranging from 10(-7)M to 3 x 10(-6)M. Following sperm exposure, both Ce(IV) and La(III) induced a decrease in sperm fertilization success at the highest tested concentration (10(-5)M). The offspring of Ce(IV)-exposed, but not of La(III)-exposed sperm displayed a significant concentration-related increase in developmental defects. The results may suggest adverse impacts in REE-exposed biota and warrant further studies of a more extended REE series. PMID:20688349

Oral, Rahime; Bustamante, Paco; Warnau, Michel; D'Ambra, Antonello; Guida, Marco; Pagano, Giovanni

2010-08-04

43

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

Microsoft Academic Search

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

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

1973-01-01

44

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

PubMed

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

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

2009-06-06

45

Effects of photoinduced toxicity of fluoranthene on amphibian embryos and larvae  

SciTech Connect

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.

Hatch, A.C. [Oregon State Univ., Corvallis, OR (United States). Dept. of Zoology; Burton, G.A. Jr. [Wright State Univ., Dayton, OH (United States). Dept. of Biological Sciences

1998-09-01

46

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 ...

47

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

Microsoft Academic Search

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

Jon W. Gordon

2002-01-01

48

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. ...

49

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

PubMed Central

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

2012-01-01

50

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

PubMed

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

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

2013-10-03

51

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

PubMed Central

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

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

2013-01-01

52

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

Microsoft Academic Search

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

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

2008-01-01

53

Marked toxicity of Albizia bernieri extracts on embryo-larval development in the medaka fish (Oryzias latipes).  

PubMed

Previous phytochemical studies have shown that the plants of the Albizia genus (Fabaceae) contain bioactive saponins, lignans, spermine alkaloids, flavonoids, glycosides phenols and pyridoxine derivatives. Their extracts sometimes display medical properties, but can have also toxic effects. The purpose of our study was to determine the in vivo toxicity of Albizia bernieri seeds in the experimental model of the medaka fish embryo, which is recommended for use in toxicity studies. Our results show clearly that incubating the embryos or larvae of the medaka fish in a medium containing A. bernieri extracts caused a dose-dependent reduction in embryo or larvae survival. Embryos exposed to an extract of A. bernieri displayed cerebral lesions, such as cell lysis and the emergence of lysosomes in the glial tissue. We conclude that when comparing with data obtained with different plant extracts tested on medaka development in our laboratory, A. bernieri displays an unusually high toxicity. Focussing on the cerebral target as well as the fish behaviour could bring more specific informations. PMID:23287727

Randriamampianina, Lovarintsoa; Offroy, Anne; Mambu, Lengo; Randrianarivo, Ranjana; Rakoto, Danielle; Jeannoda, Victor; Djediat, Chakib; Puiseux Dao, Simone; Edery, Marc

2012-12-31

54

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

PubMed

Pharmaceuticals are continually released in the environment and therefore pollution from drugs is a pressing problem in the environment. Diclofenac, 2-[(2,6-dichlorophenyl)amino]phenylacetic acid is a FDA approved non-steroidal anti-inflammatory drug (NSAID) for the treatment of inflammation. This pharmaceutical has been found as pollutant in superficial waters. Danio rerio (zebrafish) embryo has been used as a model organism for acute pollutant toxicity tests in order to identify morphological alterations in development and death rate. Through the combination of mRNA differential display and quantitative Real Time experiments, we analyzed the alterations of gene expression in zebrafish embryos left to develop in the presence of diclofenac and thereby assess the molecular mechanism involved in ecotoxicity of diclofenac polluted waters. This approach, in embryos exposed to 1.25 mg/l drug for 48 h, allowed identifying 36 different genes, with both known and unknown functions, whose transcription is differentially regulated. The identity and ontological classification of these genes is presented. The wide variety of functional classes of transcripts isolated in this screen reflects the diverse spectrum of influences operating across diclofenac exposure. Of these 36 genes, several have been selected for detailed quantitative Real Time analysis to validate the screen. Our results, for the first time, provide an insight into some of the varied and novel molecular networks following zebrafish exposure to diclofenac polluted waters. PMID:21643954

De Felice, Bruna; Copia, Luisa; Guida, Marco

2011-06-05

55

A Perspective on the Toxicity of Petrogenic PAHs to Developing Fish Embryos Related to Environmental Chemistry  

Microsoft Academic Search

Numerous studies demonstrate polynuclear aromatic hydrocarbons (PAHs) dissolved from weathered crude oil adversely affect fish embryos at 0.5 to 23 ?g\\/l. This conclusion has been challenged by studies that claim (1) much lower toxicity of weathered aqueous PAHs; (2) direct contact with dispersed oil droplets plays a significant role or is required for toxicity; (3) that uncontrolled factors (oxygen, ammonia,

Mark G. Carls; James P. Meador

2009-01-01

56

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

PubMed Central

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

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

2010-01-01

57

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

Microsoft Academic Search

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

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

1997-01-01

58

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

PubMed Central

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

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

2010-01-01

59

Humane endpoints in toxicity testing  

Microsoft Academic Search

Summary The current use of humane endpoints in the fields of animal testing for acute oral toxicity, skin and eye irritation and corrosion, and skin sensitization is presented. The data used were obtained within the framework of the regulatory activities for the development of new methods, and within the notification procedure for new chemicals in the European Union. It is

E. Schlede; W. Diener; I. Gerner

60

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...

61

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

Microsoft Academic Search

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

Edward W. Devlin

2006-01-01

62

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

PubMed

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

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

2013-08-22

63

NEW EARLY LIFE-STAGE TOXICITY TEST USING THE CALIFORNIA GRUNION (LEURESTHES TENUIS) AND RESULTS WITH CHLORPYRIFOS  

EPA Science Inventory

California grunion were continuously exposed as embryos and fry to technical chlorpyrifos in two toxicity tests conducted in the same exposure apparatus. The first test, a 35-day early life-stage (ELS) test, began with approximately 2.5-day-old embryos that were exposed in flow-t...

64

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

PubMed

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

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

2006-04-01

65

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

PubMed

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

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

2006-12-01

66

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

PubMed

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

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

2011-01-13

67

Toxicity of a pendimethalin containing herbicide formulation and three heavy metals in chicken embryos.  

PubMed

The toxic effects of a widely used herbicide (Stomp 330 containing 33% pendimethalin as active ingredient) applied alone or in combination with three heavy elements (copper sulphate, cadmium sulphate and lead acetate) modelling the heavy metal load of the environment were studied on chicken embryos with injection treatment. The treatment was done on day 0 of incubation. Solutions and emulsions of different concentrations were made from the test materials and injected in 0.1 ml volume into the air space of eggs. The macroscopical evaluations were done on day 19 of the incubation. Summarizing the findings, it can be established that the individual administration of the 33% pendimethalin containing herbicide formulation was less toxic compared to the control group than the simultaneous administration of the pesticide and heavy elements. As compared with each other the results from the combined administrations of the 33% pendimethalin containing herbicide formulation and heavy elements the simultaneous administration of cadmium and the herbicide caused the highest embryomortality while the incidence of developmental anomalies were the highest in the interaction study of the copper and the pesticide. PMID:17390780

Juhász, E; Szabó, R; Keserü, M; Budai, P; Várnagy, L

2006-01-01

68

Investigation of developmental toxicity and teratogenicity of antiemetics on rat embryos cultured in vitro.  

PubMed

In this study, we aimed to investigate and compare the direct toxic and teratogenic effects of dimenhydrinate, metoclopramide and trimethobenzamide HCl, antiemetic drugs on embryonic growth and development in cultured rat embryos. Embryos were explanted on day 9.5 of gestation and cultured. Whole rat serum was used as a culture medium for the control group while different concentrations of dimenhydrinate (2.5-20 ?g/ml), metoclopramide (10-50 ?g/ml) and trimethobenzamide HCl (25-100 ?g/ml) were added to serum for the experimental groups. Effects of antiemetics on embryonic developmental parameters were compared, and embryos were evaluated for the presence of any malformations. Also, the total DNA was extracted from the cells to determine the fragmentation of nuclear DNA of embryonic cells. Compared with the control embryos, the antiemetics significantly decreased all growth and developmental parameters dose dependently. There was no difference regarding the fragmentation of nuclear DNA of the all used agents and controls. Amongst the agents, trimethobenzamide HCl was found to have more toxic and teratogenic potential, and metoclopramide appears to be the least toxic antiemetic and therefore could be more safely used and might be preferred for the treatment of nausea and vomiting in pregnancy. PMID:23002952

Fazliogullari, Z; Karabulut, A K; Uysal, I I; Unver Dogan, N; Acar, H

2012-09-25

69

Effect of preparation methods on toxicity of fullerene water suspensions to Japanese medaka embryos.  

PubMed

The physicochemical properties of fullerene water suspensions (nC(60)) and their subsequent toxicity were influenced by different preparation methods. The nC(60) suspensions were produced by three methods: toluene exchange (Tol/nC(60)), DMSO dissolving (DMSO/nC(60)), and stirring overtime (Aqu/nC(60)). The particle size, zeta potential, and nC(60) structure were strongly dependent on both the type of aggregates formed and the test medium addition. Specifically, Tol/nC(60) exhibited small and spherical closed aggregates, whereas DMSO/nC(60) and Aqu/nC(60) presented mesoscale aggregates of smaller spherical aggregates. These differences in the physicochemical properties of nC(60) determined the embryonic toxicity and oxidative stress of Japanese medaka (Oryzias latipes). The mortality and glutathione (GSH) induction of embryos were ranked in the order of Tol/nC(60)>DMSO/nC(60)>Aqu/nC(60), and the morphological malformations were in the order of DMSO/nC(60)>Tol/nC(60)>Aqu/nC(60). The mortality of Tol/nC(60) was attributed to its closely packed fullerene structure, which remained as largely underivatized C(60). The malformations of DMSO/nC(60) might have originated from the co-effect of organic solvent remaining in the fullerene colloid. To summarize, these findings clearly illustrated the need to consider the effect of preparation method on the physicochemical properties when assessing nC(60) toxicity. PMID:20723969

Kim, Ki-Tae; Jang, Min-Hee; Kim, Jun-Yeol; Kim, Sang Don

2010-08-17

70

A panel of biological tests reveals developmental effects of pharmaceutical pollutants on late stage zebrafish embryos.  

PubMed

Standard toxicological assays using the zebrafish model system evaluate lethality and teratogenicity upon exposure during the first 2 days after fertilization. We tested the biological effects of several widely used drugs on zebrafish by acute treatment for 24 h starting at late embryonic stages, between 48 and 72 h post-fertilization. For 4 out of 6 compounds, we observed a higher sensitivity of late stage zebrafish embryos for general toxicity (lethality) compared to younger embryos. Morphological defects such as edema, body curvature, delayed growth, decreased heart rate and locomotion were observed for each of the compounds tested, often at sublethal concentrations. Gene expression studies on a set of four selected genes revealed a specific regulatory pattern for the different compounds tested. Our results allow us to compare various toxicological endpoints and may contribute to the design of a rational high throughput approach using the zebrafish model. PMID:22982570

Pruvot, Benoist; Quiroz, Yobhana; Voncken, Audrey; Jeanray, Nathalie; Piot, Amandine; Martial, Joseph A; Muller, Marc

2012-09-13

71

Renewal device for test solutions in Daphnia toxicity tests  

Microsoft Academic Search

Acute toxicity tests provide information about lethality of toxic agents or mixed wastes when test organisms are exposed, Tests follow basically three types of laboratory designs: static, static with renewal, and continuous flow. The type of test method that ~s selected depends on the ob.iective of the test. Static tests are sufficient to assess the acute toxicity of effluents and

Krzysztof M. Jop; John H. Rodgers; Edmund E. Price; Kenneth L. Dickson

1986-01-01

72

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

Microsoft Academic Search

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 10 3International Atomic Energy Agency, Quai 6 to 3 10 5 M MMC, in terms of larval malformations, developmental arrest

G. Pagano; P. Degan; A. de Biase; M. Iaccarino; M. Warnau

2001-01-01

73

Chapter IV. Guidelines for Toxicity Tests  

Center for Food Safety and Applied Nutrition (CFSAN)

Text Version... Acute toxicity tests can provide preliminary information on the toxic nature of a material for which no other toxicology information is available. ... More results from www.fda.gov/downloads/food/guidanceregulation

74

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

PubMed

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

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

2010-07-01

75

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

PubMed

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

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

2008-08-14

76

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

USGS Publications Warehouse

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

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

2008-01-01

77

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

PubMed

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

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

2012-11-03

78

Invited Reviews: Developmental Toxicity Testing of Biopharmaceuticals in Nonhuman Primates: Previous Experience and Future Directions  

Microsoft Academic Search

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

Pauline L. Martin; Gerhard F. Weinbauer

2010-01-01

79

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

PubMed Central

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

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

2012-01-01

80

INCREASING THE USEFULNESS OF ACUTE TOXICITY TESTS  

EPA Science Inventory

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

81

Comparison of Methods to Obtain a Liquid Phase in Marine Sediment Toxicity Bioassays with Paracentrotus lividus Sea Urchin Embryos  

Microsoft Academic Search

Sediment toxicity bioassays using planktonic organisms are widespread tools in environmental quality assessment, but they\\u000a have limitations because the method for extracting and diluting the liquid phase may affect the final toxicity. The present\\u000a study compares the toxicity on sea urchin embryos and larvae of elutriates and pore water obtained from intertidal sediments\\u000a by various methods. The effects of mixing

R. Beiras

2002-01-01

82

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

PubMed Central

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

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

2004-01-01

83

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

PubMed

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

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

2011-06-30

84

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

EPA Science Inventory

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

85

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

EPA Science Inventory

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

86

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

PubMed

This paper details the derivation of a list of 60 reference chemicals for the development of alternatives to animal testing in ecotoxicology with a particular focus on fish. The chemicals were selected as a prerequisite to gather mechanistic information on the performance of alternative testing systems, namely vertebrate cell lines and fish embryos, in comparison to the fish acute lethality test. To avoid the need for additional experiments with fish, the U.S. EPA fathead minnow database was consulted as reference for whole organism responses. This database was compared to the Halle Registry of Cytotoxicity and a collation of data by the German EPA (UBA) on acute toxicity data derived from zebrafish embryos. Chemicals that were present in the fathead minnow database and in at least one of the other two databases were subject to selection. Criteria included the coverage of a wide range of toxicity and physico-chemical parameters as well as the determination of outliers of the in vivo/in vitro correlations. While the reference list of chemicals now guides our research for improving cell line and fish embryo assays to make them widely applicable, the list could be of benefit to search for alternatives in ecotoxicology in general. One example would be the use of this list to validate structure-activity prediction models, which in turn would benefit from a continuous extension of this list with regard to physico-chemical and toxicological data. PMID:18829120

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

2008-08-22

87

Mysids in toxicity testing — a review  

Microsoft Academic Search

The use of mysid shrimp, particularly the genusMysidopsis, along with specific testing procedures, has become accepted in aquatic toxicology. Investigators have developed methodologies for both culture and testing of these organisms. Acute and chronic (life cycle) toxicity tests in addition to dredge spoil and effluent tests with mysids are now becoming common. Attempts have been made to use mysids as

D. R. Nimmo; T. L. Hamaker

1982-01-01

88

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

SciTech Connect

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

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

1995-10-01

89

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

SciTech Connect

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

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

1995-05-01

90

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

PubMed Central

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

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

2012-01-01

91

16 CFR 1500.40 - Method of testing toxic substances.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Method of testing toxic substances. 1500.40 Section 1500.40...REGULATIONS § 1500.40 Method of testing toxic substances. The method of testing the toxic substances referred to in §...

2013-01-01

92

Integrative assessment of marine pollution in Galician estuaries using sediment chemistry, mussel bioaccumulation, and embryo-larval toxicity bioassays  

Microsoft Academic Search

An integrative assessment of environmental quality was carried out in selected sites along the Galician coast (NW Iberian Peninsula) combining analytical chemistry of seawater and sediments, bioaccumulation in the marine mussel, and embryo-larval sediment toxicity bioassays, in order to link biological and chemical criteria for the assessment of coastal pollution. Maximum values of Hg and Cu in seawater, sediment and

R Beiras; N Fernández; J Bellas; V Besada; A González-Quijano; T Nunes

2003-01-01

93

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

Microsoft Academic Search

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

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

2004-01-01

94

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

SciTech Connect

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.

Nemeth, Kimberly A. [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107 (United States); Singh, Amar V. [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107 (United States); School of Dentistry, Birth Defects Center, University of Louisville, 501 South Preston Street, Louisville, KY 40202 (United States); Knudsen, Thomas B. [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107 (United States) and School of Dentistry, Birth Defects Center, University of Louisville, 501 South Preston Street, Louisville, KY 40202 (United States)]. E-mail: thomas.knudsen@louisville.edu

2005-08-07

95

Bioequivalence approach for whole effluent toxicity testing  

SciTech Connect

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

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

2000-01-01

96

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

Microsoft Academic Search

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

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

1990-01-01

97

Avian models for toxicity testing  

USGS Publications Warehouse

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

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

1984-01-01

98

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...

99

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

PubMed

Even though petrochemical contamination frequently occurs in the form of oil spills, it is thought that a greater danger to coastal habitats is posed by chronic petrochemical toxicity associated with urban run-off, in which gasoline water-soluble-fraction (WSF) plays an important role. The hypothesis of the entrepreneurs, who were associated to the scientists uncharged of this research, was that recycled petrochemical waste may provide different gasoline formulations, having different toxic properties; the correlation between the gasoline formulations and their components' toxicological effects might contribute to the reformulation of the products, in such a way that the gasoline generated could be less toxic and less harmful to the environment. The aim of this research was to determine the toxic effects of 14 different types of gasoline (formulated, in accordance with National Petroleum Agency standards, from petrochemical waste), on Tetraselmis chuii (microalgae culture) and Crassostrea rhizophorae (embryos). Microalgae and oyster embryos were exposed to different gasoline formulations water-soluble fractions (WSF) at a range of concentrations (0%, 4.6%, 10.0%, 22.0%, 46.0%, and 100%), for 96 and 24h, respectively. The tests were carried out under controlled conditions. End-points have been CI50-96h (concentration causing 50% growth inhibition in microalgae cultures) and EC50-24h (concentration causing abnormalities on 50% of the exposed embryos). Through these procedures, gasoline formulations, which represent the lowest environmental risk, were selected. Bioassays carried out on the 8 different gasoline components aimed to correlate gasoline toxicity with the toxic potential of its components. The analysis of principal components showed that the C9DI, a mixture of aromatic hydrocarbons of 9 carbon atoms, had the highest level of toxic potential, followed by C9S (a mixture of aromatics with 9-11 carbon atoms) and heavy naphtha. The results showed gasoline formulations 1-4 (monoaromatic hydrocarbons being the most conspicuous components) to be the least toxic, whilst formulations 12-14 (having higher content of C9DI, C9S and naphtha) were found to be the most harmful to organisms. This study led to the identification of the most toxic WSF gasoline components (C9DI and C9S), and to the possibility of developing more eco-compatible gasoline formulations. PMID:16930589

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

2006-08-22

100

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

SciTech Connect

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

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

2007-03-15

101

Intra- and intertreatment variability in reference toxicant tests: Implications for whole effluent toxicity testing programs  

SciTech Connect

Whole effluent toxicity tests are used in permitting programs across the US to determine whether effluents are potentially toxic to aquatic biota in receiving environments. In cases where whole effluent toxicity tests indicate unacceptable toxicity, corrective measures or further testing may be required. To be consistent and fair to permit holders, whole effluent toxicity test outcomes should not be strongly influenced by intra- and interlaboratory variability. In this study, the authors quantified intra- and interlaboratory variability for four species-data type combinations using the results of reference toxicant tests compiled from many laboratories in recent years. For each set of test results, they conducted a regression analysis using the generalized linear models framework. The results indicated that the coefficient of variation for intralaboratory 25% effective concentration values varied from 15.7% for number of young of Ceriodaphnia dubia in laboratory CD4 to 122% for mortality of Menidia beryllina in laboratory MB3. Interlaboratory variability was small for both mortality and number of young of C. dubia. Interlaboratory variability for mortality and biomass of M. beryllina, however, was very high. Their study shows that permit toxicity limits can be exceeded because of factors other than effluent toxicity, particularly when the limits are based on testing of M. beryllina.

Moore, D.R.J.; Warren-Hicks, W.; Parkhurst, B.R.; Teed, R.S.; Baird, R.B.; Berger, R.; Denton, D.L.; Pletl, J.J.

2000-01-01

102

Low-level pyrene exposure causes cardiac toxicity in zebrafish (Danio rerio) embryos.  

PubMed

It is widely accepted that the most abundant polycyclic aromatic hydrocarbons (PAHs) in weathered crude oils is cardiotoxic. Although PAHs toxic endpoints show strong correlation with the aryl hydrocarbon receptor (AhR), a ligand activated transcription factor, and is thought to be a potent inducer of cytochrome P4501A, the action mechanism of PAHs on vertebrate cardiovascular development and disease is unclear. Herein, we address the cardiac developmental effects of exposure to the weak AhR agonist pyrene on the early life-stages of zebrafish. Embryos were exposed to 0, 0.05, 0.5, 5, and 50 nmol/L pyrene up to 72h post-fertilization (hpf). Pyrene-treated embryos showed dose-dependent heart abnormalities, such as pericardial edema and cardiac looping defects. Changes in AhR1a, AhR1b, AhR2, and Cyp1A expression were assessed by real-time RT-PCR. The results showed that low-level pyrene failed to alter these genes expression. However, the homeodomain transcription factor Nkx2.5, which plays an essential role in the development of the cardiovascular system, was down-regulated in a dose-dependent manner by pyrene exposure. The bone morphogenetic protein 2b (Bmp2b), which has been identified as the upstream gene of Nkx2.5, also was inhibited in a dose-dependent manner after treatment with pyrene. Taken together, these data indicated that embryonic exposure of zebrafish to low-level environmental pyrene disrupt normal cardiac development and alter expression of defective cardiac differentiation related genes. PMID:22446823

Zhang, Youyu; Wang, Chonggang; Huang, Lixing; Chen, Rong; Chen, Yixin; Zuo, Zhenghong

2012-03-03

103

Toxic Element Testing with Clinical Specimens  

Microsoft Academic Search

Elements are the basis of all things. However, human exposure to significant amounts of some elements can lead to adverse\\u000a health effects including death. Laboratory testing can help identify unrecognized exposures as well as monitor-associated\\u000a decontamination efforts. Regular testing is also important to identify exposures in populations that are at high risk for\\u000a exposure to a specific toxic element. For

Gwendolyn A. McMillin; Joshua A. Bornhorst

104

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

SciTech Connect

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

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

1986-01-01

105

Earthworm bioassays: Adopting techniques from aquatic toxicity testing  

Microsoft Academic Search

Current theories suggest that the effective concentration of soil contaminants is that fraction that resides in the hydrosphere of soil particles; therefore, parallels may be drawn between toxicity testing in soil, sediment and water. Certain practices and concepts used in aquatic toxicity testing may be adapted into soil toxicity testing procedures and increase the general understanding of the toxicity of

R. P. Lanno; L. S. McCarty

1997-01-01

106

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

PubMed Central

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

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

2013-01-01

107

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

Microsoft Academic Search

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

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

2008-01-01

108

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....

109

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

SciTech Connect

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

Becker, M.C.

1991-05-01

110

Toxicity and enantiospecific differences of two ?-blockers, propranolol and metoprolol, in the embryos and larvae of zebrafish (Danio rerio).  

PubMed

The risk presented by ?-blockers on aquatic organisms remains uncertain, particularly given the enantiospecific differences in toxicity of chiral ?-blockers. In this study, the toxicity of two ?-blockers, propranolol and metoprolol, was determined. The 96-h LC50 of propranolol in the zebrafish larvae was 2.48 mg/L, whereas 50 mg/L metoprolol did not result in death. Both ?-blockers decreased the heart rate and hatching rate and increased the mortality of the zebrafish embryos. Among these indicators, the heart rate was the most sensitive. However, the acute larval and embryo toxicity results displayed no enantioselectivity. Additionally, the transcriptional response of the genes encoding the ?-adrenergic receptors and those involved in other physiological processes, including the antioxidant response, detoxification, and apoptosis, in zebrafish larvae exposed to the ?-blockers was examined. Although the changes in gene transcription were fairly minor, significant enantioselectivity was observed for ?-blockers, suggesting that the transcriptional response was more sensitive for the evaluation of enantiospecific toxicity. Based on these results, the pharmaceutical drugs were not expected to pose a risk to fish; however, this conclusion should not be considered final. These results also demonstrated that the enantiospecific toxicity of chiral ?-blockers should be investigated when performing an ecological risk assessment. © 2013 Wiley Periodicals, Inc. Environ Toxicol, 2013. PMID:23661550

Sun, Liwei; Xin, Lihua; Peng, Zuhua; Jin, Rong; Jin, Yuanxiang; Qian, Haifeng; Fu, Zhengwei

2013-05-10

111

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

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

2009-07-01

112

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

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

2010-07-01

113

40 CFR 795.120 - Gammarid acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...2012-07-01 false Gammarid acute toxicity test. 795.120 Section 795.120 Protection...CONTROL ACT (CONTINUED) PROVISIONAL TEST GUIDELINES Provisional Environmental... § 795.120 Gammarid acute toxicity test. (a) Purpose. This...

2012-07-01

114

Reproductive Toxicity Testing: Evaluating and Developing New Testing Systems  

Microsoft Academic Search

Reproductive toxicity testing systems are used by national and international regulatory agencies. Protocols have not been standardized between agencies or even within certain agencies. Although there have been efforts at standardization, a certain amount of the differences between testing protocols is a reflection of the needs of the particular agency. New developments in in vitro techniques might lead to new

J. C. Lamb

1985-01-01

115

Automated Phenotype Recognition for Zebrafish Embryo Based In Vivo High Throughput Toxicity Screening of Engineered Nano-Materials  

PubMed Central

A phenotype recognition model was developed for high throughput screening (HTS) of engineered Nano-Materials (eNMs) toxicity using zebrafish embryo developmental response classified, from automatically captured images and without manual manipulation of zebrafish positioning, by three basic phenotypes (i.e., hatched, unhatched, and dead). The recognition model was built with a set of vectorial descriptors providing image color and texture information. The best performing model was attained with three image descriptors (color histogram, representative color, and color layout) identified as most suitable from an initial pool of six descriptors. This model had an average recognition accuracy of 97.40±0.95% in a 10-fold cross-validation and 93.75% in a stress test of low quality zebrafish images. The present work has shown that a phenotyping model can be developed with accurate recognition ability suitable for zebrafish-based HTS assays. Although the present methodology was successfully demonstrated for only three basic zebrafish embryonic phenotypes, it can be readily adapted to incorporate more subtle phenotypes.

Liu, Rong; Lin, Sijie; Rallo, Robert; Zhao, Yan; Damoiseaux, Robert; Xia, Tian; Lin, Shuo; Nel, Andre; Cohen, Yoram

2012-01-01

116

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

PubMed

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

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

2010-09-15

117

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

Microsoft Academic Search

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 mug\\/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

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

2011-01-01

118

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

EPA Science Inventory

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

119

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

PubMed

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

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

2010-07-22

120

Principles of Toxicity Testing with Marine Unicellular Algae.  

National Technical Information Service (NTIS)

Toxicity testing with unicellular algae requires application of the principles of phycology and microbiology to culturing, handling, and exposing the organisms. The brief review describes major aspects of algal toxicity testing, including growth curves, f...

G. E. Walsh

1988-01-01

121

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 ...

122

TOXICITY OF GUTHION AND GUTHION 2S TO XENOPUS LAEVIS EMBRYOS  

EPA Science Inventory

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

123

Individual and joint toxic effects of pentachlorophenol and bisphenol A on the development of zebrafish ( Danio rerio) embryo  

Microsoft Academic Search

Investigation of the toxicological effects of pentachlorophenol (PCP) and bisphenol A (BPA) alone and in combination was carried out following the method of the early life stage (ELS) test on zebrafish embryos. Both chemicals revealed lethal and sub-lethal effects, such as no blood flow, cardiac edema, delayed hatching, and tail malformations. According to their median effective concentrations (EC50 values) in

Zhenghua Duan; Lin Zhu; Lingyan Zhu; Yao Kun; Xiaoshan Zhu

2008-01-01

124

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...

125

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...

126

Assessment of toxic interactions of heavy metals in multi-component mixtures using sea urchin embryo-larval bioassay.  

PubMed

The toxicities of copper, lead, zinc and cadmium ions and various concentrations of mixtures of them were studied using sea urchin (Strongylocentyotus intermedius) embryo-larval bioassay. Toxic unit analysis was used to determine type of joint action for each mixture combination (binary, ternary and quaternary). For the majority of the binary combinations, the interactions were of synergistic nature, but in ternary or quaternary mixtures, the joint action was mainly concentration additive, while antagonism was only observed for two mixtures (Cu+Pb and Zn+Cd) among all the 11 combinations. Two prevailing theoretical models: the concentration addition (CA) model and the independent action (IA) model were used to predict the mixture toxicities. The weak correlation obtained (R?0.55) indicated that the hypotheses of mode of action involved in the two models to some extent failed to describe the behavior of the mixture system. Then a novel bio-concentration factor-based model was developed and was successful to predict the toxicities of mixtures, with an obtained R of 0.92. This model indicated that in a mixture system of heavy metals, the joint toxicity was mainly determined by the combined action of bio-concentrations of metals other than the simply similar (CA) or dissimilar (IA) modes of action of the mixture components. PMID:20854890

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

2010-09-18

127

Automated Test Systems for Toxic Vapor Detectors.  

National Technical Information Service (NTIS)

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 ...

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

1997-01-01

128

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

Microsoft Academic Search

Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to

Nicola A Davies; Mark E Hodson; Stuart Black

2003-01-01

129

In vivo testing for gold nanoparticle toxicity.  

PubMed

A technique for measuring the toxicity of nanomaterials using a murine model is described. Blood samples are collected via submandibular bleeding while urine samples are collected on cellophane sheets. Both biosamples are then analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES) for nanotoxicity. Blood samples are further tested for immunological response using a standard Coulter counter. The major organs of interest for filtration are also digested and analyzed via ICP-OES, producing useful information regarding target specificity of the nanomaterial of interest. Collection of the biosamples and analysis afterward is detailed, and the operation of the technique is described and illustrated by analysis of the nanotoxicity of an injection of a modified tiopronin monolayer-protected cluster. PMID:23749578

Simpson, Carrie A; Huffman, Brian J; Cliffel, David E

2013-01-01

130

Toxicity of ebrotidine on reproduction. Toxicity on fertility and general reproductive performance, embryo-fetal toxicity and peri- and postnatal toxicity.  

PubMed

Reproduction toxicity studies of ebrotidine (N-[(E)-[[2-[[[2-[(diaminomethylene)amino]-4-thiazolyl]methyl] thio]ethyl]amino]methylene]-4-bromo-benzenesulfonamide, CAS 100981-43-9, FI-3542) are presented in this paper. Rats dosed with 50, 200 and 500 mg/kg p.o. of ebrotidine were used for the fertility and peri- and postnatal toxicity studies, and rabbits dosed with 25, 100 and 250 mg/kg and rats dosed with 50, 200 and 500 mg/kg of ebrotidine were used for the embryotoxicity study. The fertility study was designed in accordance with a 2-generation study protocol. The results showed that ebrotidine did not interfere with male and female gametogenesis, fertility, organogenesis, postnatal development and lactation in F0 or F1 animals. Only general or non-specific effects were attributed to treatment, such as a lower weight gain in parents or fetuses in rats, or a somewhat slower bone calcification in rats, which was shown to be recoverable and had no peri- or postnatal repercussions. Neither did the fertility study reveal a possible longer duration of gestation nor did the peri- and postnatal study show a lower weight of the F1 offspring. There was only an increase in rabbit embryonic mortality, probably related to some cases of abortion at the high dose. No potential antiandrogenic effect on the reproductive function has been found. Among the different doses used in both animal species, the maximum toxic effect-free dose was that of 25 mg/kg. PMID:9205753

Romero, A; Grau, M T; Villamayor, F; Sacristán, A; Ortiz, J A

1997-04-01

131

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

Microsoft Academic Search

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

Roger B. Yeardley; James M. Lazorchak; Michael A. Pence

1995-01-01

132

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

PubMed Central

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

Kimm-Brinson, K L; Ramsdell, J S

2001-01-01

133

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...

134

Toxicity of the 13 priority pollutant metals to Vibrio fisheri in the Microtox chronic toxicity test.  

PubMed

The Microtox Acute Toxicity Test has been successfully used to measure the toxicity of metals and other pollutants at high concentrations (ppm) in selected environmental samples. However, metals and other toxicants are often found in much lower concentrations (ppb) in many municipal wastewaters and receiving waters. In order to assess the toxicity of these pollutants in these samples, a more sensitive toxicity assay is needed. The Microtox chronic toxicity test has been developed to measure the sublethal effect of toxicants over multiple generations of the test species, Vibrio fisheri. In this study, the toxicity of the 13 priority pollutant metals [i.e. As, Se, Cd, Cr (III and VI), Cu, Pb, Sb, Ag, Tl, Zn, Be, Hg and Ni] to V. fisheri was evaluated using the Microtox chronic toxicity test. In this test, the inhibitory concentration (IC), lowest observable effect concentration (LOEC), and no observable effect concentration (NOEC) were obtained after 22-h of incubation at 27+/-1 degrees C, by comparing the light output of the control to that of the test sample. Among the 13 priority pollutant metals, beryllium (Be) was found to be the most toxic in the test (LOEC=0.742-1.49 microg/l) while thallium (Tl) was the least toxic (LOEC=3840-15300 microg/l). The LOECs for copper (as Cu) and lead (Pb) in reagent (ASTM Type I) water were 6.78-13.6 microg/l and 626-1251 microg/l, respectively. The toxicity of copper sulfate (as Cu) in reagent water was shown and significantly reduced with the addition of natural organic matter (fulvic acid) or EDTA to the sample. The LOEC values for the 13 priority pollutant metals in this test were comparable to or lower than those reported for commonly used aquatic toxicity tests, such as the Ceriodaphnia dubia assay. PMID:14987925

Hsieh, Chi-Ying; Tsai, Meng-Hsiun; Ryan, David K; Pancorbo, Oscar C

2004-03-01

135

Developmental toxicity, uptake and distribution of sodium chromate assayed by frog embryo teratogenesis assay-Xenopus(FETAX).  

PubMed

The embryotoxicity and teratogenicity of Cr(VI) on the survival and morphology of the anuran Xenopus laevis have been assessed by frog embryo teratogenesis assay-Xenopus (FETAX). The lethal median (LC(50)) and teratogenic median (TC(50)) concentration values of Cr(VI) were 890 microM and 260 microM, respectively. The calculated teratogenic index (TI) value was 3.42, suggesting that hexavalent chromium has a teratogenic potential. Malformations of embryos included lifting of the body, coiling of the tail and body oedema. Furthermore, the chromium salt caused significant growth retardation at 25 microM exposure concentrations. The use of radiolabelled (51)Cr(VI) allowed the determination of the time course uptake of Cr in Xenopus exposed to concentrations ranging from 0.025 to 500 microM. The evaluation of its distribution into the body (head-abdomen-tail) was evaluated at different exposure times. Chromium is taken up at 24 h by Xenopus embryos for all concentrations tested. At 48 h post fertilization (stage of larva) the amount of Cr accumulated by the two-day-old larva ranged from 0.42 to 580 pg mg(-1) wet weight at 0.025 and 500 microM respectively. These amounts were lower than those at 24 h (2.77 to 11016 pg mg(-1) wet weight embryo) reaching values of the same order of magnitude at 120 h (five-days-old larva). Since at 48 h Xenopus development leads to a swimming embryo, the observed uptake at 24 h could be the result of the binding of Cr to jelly coat compounds surrounding the embryo body as confirmed by gel filtration experiments on (51)Cr-jelly coat. The interaction of Cr with jelly coat is in agreement with the role of jelly coat in protecting the embryo against pathogen and chemical toxins to ensure fertilization. This work further supports the hypothesis that Cr contamination of surface waters could contribute to explain the reported worldwide depletion of frog population. PMID:19540565

Bosisio, Stefano; Fortaner, Salvador; Bellinetto, Sonia; Farina, Massimo; Del Torchio, Riccardo; Prati, Mariangela; Gornati, Rosalba; Bernardini, Giovanni; Sabbioni, Enrico

2009-06-21

136

Toxicity testing of trinitrotoluene-contaminated soil composts  

Microsoft Academic Search

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

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

1997-01-01

137

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...algae recommended as test organisms for this test are the freshwater green alga, Selenastrum capricornutum, and the marine diatom, Skeletonema costatum. Algae to be used in acute toxicity tests may be initially obtained from commercial sources...

2010-07-01

138

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...algae recommended as test organisms for this test are the freshwater green alga, Selenastrum capricornutum, and the marine diatom, Skeletonema costatum. Algae to be used in acute toxicity tests may be initially obtained from commercial sources...

2009-07-01

139

40 CFR 797.1050 - Algal acute toxicity test.  

Code of Federal Regulations, 2013 CFR

...algae recommended as test organisms for this test are the freshwater green alga, Selenastrum capricornutum, and the marine diatom, Skeletonema costatum. Algae to be used in acute toxicity tests may be initially obtained from commercial sources...

2013-07-01

140

EVALUATION OF A FATHEAD MINNOW 'PIMEPHALES PROMELAS' EMBRYO-LARVAL TEST GUIDELINE USING ACENAPHTHENE AND ISOPHORONE  

EPA Science Inventory

A set of 4 embryo-larval bioassays (2) each with isophorone and acenaphthene, respectively, were conducted with the fathead minnow, Pimephales promelas. The objective of the study was to evaluate a specific method for this type of test. The no effect levels when compared to the c...

141

Rabbit whole embryo culture.  

PubMed

Although the rabbit is used extensively in developmental toxicity testing, relatively little is known about the fundamental developmental biology of this species let alone mechanisms underlying developmental toxicity. This paucity of information about the rabbit is partly due to the historic lack of whole embryo culture (WEC) methods for the rabbit, which have only been made available fairly recently. In rabbit WEC, early somite stage embryos (gestation day 9) enclosed within an intact amnion and attached to the visceral yolk sac are dissected from maternal tissues and placed in culture for up to 48 h at approximately 37°C and are continuously exposed to an humidified gas atmosphere mixture in a rotating culture system. During this 48 h culture period, major phases of organogenesis can be studied including cardiac looping and segmentation, neural tube closure, and development of anlagen of the otic system, eyes and craniofacial structures, somites and early phases of limb development (up to bud stage), as well as expansion and closure of the visceral yolk sac around the embryo. Following completion of the culture period, embryos are evaluated based on several growth and development parameters and also are assessed for morphological abnormalities. The ability to sustain embryo development independent of the maternal system allows for exposure at precise development stages providing the opportunity study the direct action of a teratogen or one of its metabolites on the developing embryo. Rabbit WEC is perhaps most useful when used in conjunction with rodent WEC methods to investigate species-specific mechanisms of developmental toxicity. PMID:22669668

Marshall, Valerie A; Carney, Edward W

2012-01-01

142

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

PubMed

More than 8.2 billion ha of cropland, gardens, and forests are treated with the herbicide glyphosate each year. Whereas the toxicity of glyphosate and associated adjuvants has been measured in other vertebrates, few, if any, studies have looked at their effects in reptiles. In some instances, management of turtle habitat requires control of successional stages through application of herbicides. Adults and juvenile turtles may be exposed directly, whereas embryos may contact the chemicals through the soil. In the present study, we exposed eggs of red-eared sliders (Trachemys scripta elegans) to single applications of herbicide ranging from 0 to 11,206 ppm wet weight of glyphosate in Glypro and 0 to 678 ppm of the surfactant, LI700. Hatching success at the highest concentration was significantly lower (73%) than in other treatments (80-100%). At hatch, turtles at the highest concentration weighed less than those at other concentrations. During a 14-d holding period, we observed dose-response relationships in the ability of hatchlings to right themselves when turned on their backs. At the end of the holding period, hatchlings at the highest dose level were still lighter, and somatic indices were lower, than those in other treatments. Genetic damage, as measured by flow cytometry, increased with treatment concentration except for the highest dose. We conclude that because of the high concentrations needed to produce effects and the protection offered by several centimeters of soil or sediment, glyphosate with LI700 poses low levels of risk to red-eared slider embryos under normal field operations with regards to the endpoints measured in the present study. Carelessness in handling glyphosate or failure to follow label directions may produce adverse effects. There also is a risk that the health of turtle embryos may be affected in ways not measured in the present study. PMID:17022419

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

2006-10-01

143

Selenoneine, a Novel Selenium-Containing Compound, Mediates Detoxification Mechanisms against Methylmercury Accumulation and Toxicity in Zebrafish Embryo.  

PubMed

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

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

2013-05-25

144

Toxicity testing of trinitrotoluene-contaminated soil composts  

SciTech Connect

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

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

1997-10-01

145

Comparison of Bulk Sediment and Sediment Elutriate Toxicity Testing Methods  

Microsoft Academic Search

Numerous methods exist for assessing the potential toxicity of sediments in aquatic systems. In this study, the results from\\u000a 10-day bulk sediment toxicity test methods using Hyalella azteca and Chironomus tentans were compared to results from 96-h Pimephales promelas and Ceriodaphnia dubia renewed acute toxicity tests conducted using elutriate samples prepared from the same sediments. The goal of the study

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

2010-01-01

146

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

ERIC Educational Resources Information Center

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

Porntrai, Supaporn; Damrongphol, Praneet

2008-01-01

147

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

USGS Publications Warehouse

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-effluent toxicity tests using those two species. If the responses of specific listed species are important for management decisions, our study supports the value in developing culture and testing procedures for those species. ?? 2005 Springer Science+Business Media, Inc.

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

148

Studies on the Nature and Genetic Control of an Antigen in Normal Chick Embryos which Reacts in the COFAL Test  

Microsoft Academic Search

SUMMARY Chick embryos from the inbred Reaseheath I line of chickens contained a complement-fixing antigen which reacted in the COFAL test, whereas em- bryos from the inbred Reaseheath C line lacked the antigen. In cross-bred embryos between the I and C lines the antigen segregated in accordance with the hypothesis that the presence of the antigen was controlled by a

L. N. Payne; R. C. Chubb

1968-01-01

149

Toxicity Tests for Ensuring Succesful Industrial Wastewater Treatment Plant Operation  

NASA Astrophysics Data System (ADS)

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

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

2009-01-01

150

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...

151

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

SciTech Connect

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

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

1986-02-01

152

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

SciTech Connect

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.

Neilson, A.H.; Allard, A.S.; Fischer, S.; Malmberg, M.; Viktor, T. (Swedish Environmental Research Institute, Stockholm (Sweden))

1990-08-01

153

Resolving some practical questions about Daphnia acute toxicity tests  

Microsoft Academic Search

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 ECââ values for

Y. Barera; W. J. Adams

1981-01-01

154

INTRALABORATORY PRECISION OF SALTWATER SHORT-TERM CHRONIC TOXICITY TESTS  

EPA Science Inventory

Short-term chronic toxicity tests using five salt-water species-two fishes, a mysid, a sea urchin, and a macro-alga- were developed. opper sulfate and sodium dodecyl sulfate were used as representative toxicants. oefficients of variation for LC50 results ranged from 1.8 to 46.4%....

155

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

PubMed

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

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

2009-09-15

156

Inter and Intra-Laboratory Testing of the Daphnia magna IQ Toxicity Test  

Microsoft Academic Search

The United States Environmental Protection Agency (USEPA), through the Clean Water Act has mandated toxicity testing as part of routine monitoring of effluent discharges. Many state agencies have implemented these regulations and included toxicity limits in discharge permits and penalties for non-compliance. Although standardized bioassay protocols have been utilized to assess compliance (USEPA guidance), results of toxicity tests are usually

K. R. Hayes; W. S. Douglas; J. Fischer

1996-01-01

157

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

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPPT-2003-0006; FRL-8872-5] Toxic Substances Control Act Chemical Testing...test data on five chemicals listed in the Toxic Substances Control Act (TSCA) section...Office of Pollution Prevention and Toxics, Environmental Protection Agency,...

2011-06-29

158

Chlorinated phenol toxicity by bacterial and biochemical tests  

SciTech Connect

The aim of the present investigation, carried out using E. coli as the test organism and poly-chlorophenols as the toxic organic compounds, was to define: (i) the activity ranges of different chlorinated phenols in the series from monochlorophenol to pentachlorophenol; (ii) the effect of the above mentioned compounds on growth and viability parameters, correlating experimental results with those obtained by enzymatic activities (dehydrogenase and beta-galactosidase); (iii) the relationships between toxicity and some physico-chemical properties of the considered organic compounds. The choice of chlorophenols depends on their implication in important industrial cycles and on their high toxicity for biological systems, so that their probable presence in the final effluents can be regarded also in terms of environmental toxicity. The phenol was selected as representative organic pollutant and the toxicity of other compounds was also expressed as relative phenol toxicity.

Cenci, G.; Caldini, G.; Morozzi, G.

1987-05-01

159

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

PubMed

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

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

1996-01-01

160

TOXICITY TESTING, RISK ASSESSMENT, AND OPTIONS FOR DREDGED MATERIAL MANAGEMENT  

EPA Science Inventory

Programs for evaluating proposed discharges of dredged material into waters of the United States specify a tiered testing and evaluation protocol that includes performance of acute and chronic bioassays to assess toxicity of the dredged sediments. Although these evaluations refl...

161

Status and Applications of Echinoid ('Phylum echinodermata') Toxicity Test Methods.  

National Technical Information Service (NTIS)

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 vario...

S. Bay R. Burgess D. Nacci

1993-01-01

162

Enzyme biosynthesis in bacteria as a basis for toxicity testing  

SciTech Connect

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

Dutton, R.J.

1988-01-01

163

Bacterial and enzymatic bioassays for toxicity testing in the environment  

SciTech Connect

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

Bitton, G.; Koopman, B. (Department of Environmental Engineering Sciences, University of Florida, Gainesville (United States))

1992-01-01

164

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

EPA Science Inventory

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

165

Current and Future Needs for Developmetal Toxicity Testing (Journal Article)  

EPA Science Inventory

A review is pesented fo the use of developmental toxicity testing in U.S. and international regulatory assessment of human health risks associated wih exposures to pharmaceuticals (human and veterinary), chemicals (agricultural, industral, and environmental), food additives, cosm...

166

The way forward in reproductive/developmental toxicity testing.  

PubMed

The use of experimental animals in reproductive toxicity testing is critically reviewed on the occasion of the 50th anniversary of the publication of the Three Rs concept by Russell and Burch, since there is major concern that reproductive toxicity testing will significantly increase due to the requirements of the EU Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) system. A comparison of the test guidelines for drugs, agrochemicals and industrial chemicals shows that, for historical reasons, significantly different testing strategies are applied. The current status of development and validation of in vitro tests in reproductive toxicology is also critically evaluated. The mouse embryonic stem cell test (mEST) is the most advanced and promising of the in vitro tests. Although it has not yet been accepted for regulatory purposes, its use in preclinical drug development is well established. Moreover, promising molecular endpoints have been established in the mEST, including proteomic and toxicogenomic endpoints. Preliminary results have been obtained with a human EST (hEST). In addition, an overview is given on new in vitro reproductive toxicity tests that are currently being developed in the EU FP6 project, ReProTect, since the ReProTect test battery, which covers the essential steps of female and male fertility, implantation and embryotoxicity, holds promise for use as a screening assay for reproductive toxicity testing according to the EU REACH legislation. However, since validated in vitro methods will not be available in the short term, opportunities for the refinement of the standard in vivo tests are discussed, in order to reduce the numbers of animal used in reproductive toxicity testing. Finally, recommendations for toxicity testing in the 21st century call for the harmonisation of test methods across all areas of regulatory testing as a first step. Since the REACH system testing framework for industrial chemicals is driven by the reproductive safety testing requirements of agrochemicals, a shift is proposed to exposure-driven testing of industrial chemicals. In particular, the implementation of a new 'extended one-generation reproductive toxicity study' (EOGRTS), which includes triggers for additional testing for fertility, developmental neurotoxicity and immunotoxicity, would significantly reduce test animal numbers. It is concluded that in vitro methods hold great promise for reproductive toxicity testing in the 21st century, e.g. the ReProTect in vitro battery and the embryonic stem cell (ESC) technology focusing on molecular endpoints in both the mEST and the hEST. PMID:20105000

Spielmann, Horst

2009-12-01

167

Rice seed toxicity tests for organic and inorganic substances  

USGS Publications Warehouse

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

Wang, W.

1994-01-01

168

Gender-dependent problems in toxicity tests with Ceriodaphnia dubia  

SciTech Connect

The 7-d, three-brood Ceriodaphnia chronic toxicity test developed by Mount and Norberg is used to assess biological quality of water and wastewaters. The test is becoming widely accepted because it involves simple procedures, uses easily measurable and biologically meaningful endpoints (survival and fecundity), and uses a microcrustacean known to be relatively sensitive to various toxicants. The test uses individual animals as true replicates, and is relatively powerful statistically. Because male and female Ceriodaphnia neonates cannot be readily distinguished from one another, a 7-d C. dubia test started with neonates produced by females from stressed cultures may include an initially indeterminant number of males. The presence of males (which can be ascertained with certainty only when the test is nearly complete) can affect interpretation of toxicity test results. In this paper the results of toxicity tests of water samples from streams near the Oak Ridge National Laboratory are used to show the extent to which the presence of male C. dubia can confound the interpretation of a 7-d Ceriodaphnia test's fecundity endpoint. The authors also show the results of short-term experiments suggesting that male C. dubia are more sensitive than females to cadmium and phenol, and discuss the statistical and practical implications of the problems caused by the presence of males in chronic toxicity tests with this species.

Haynes, G.J.; Stewart, A.J.; Harvey, B.C. (Oak Ridge National Laboratory, TN (USA))

1989-08-01

169

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

Microsoft Academic Search

This paper details the derivation of a list of 60 reference chemicals for the development of alternatives to animal testing in ecotoxicology with a particular focus on fish. The chemicals were selected as a prerequisite to gather mechanistic information on the performance of alternative testing systems, namely vertebrate cell lines and fish embryos, in comparison to the fish acute lethality

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

2008-01-01

170

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 Irwinâ??s screen, which assess the neurological, motor, and functional integrity of the subject...

171

Development of a Sperm Cell Toxicity Test for Marine Waters.  

National Technical Information Service (NTIS)

Preliminary methods for conducting a quick and sensitive sperm cell toxicity test for marine waters have been developed. This paper presents a simple static test in which sea urchin or sand dollar sperm cells are exposed to test or control solutions for s...

P. A. Dinnel Q. J. Stober S. C. Crumley R. E. Nakatani

1982-01-01

172

Acute toxic tests of rainwater samples using Daphnia magna  

Microsoft Academic Search

Rainwater samples were collected at Isogo Ward of Yokohama City, Japan, from 23 June to 31 July 2003. The toxic potency of pollutants present in 13 rainwater samples was tested using Daphnia magna. Most test animals died within 48h in five test solutions that were prepared from rainwater samples. On the other hand, when nonpolar compounds such as pesticides were

Manabu Sakai

2006-01-01

173

Test chambers and test procedures for in situ toxicity testing with zooplankton  

SciTech Connect

Ecotoxicity assessment is usually done by classical tests under controlled conditions. However, field situations may not be accurately predicted by laboratory testing. In situ testing is a pertinent way for assessing the ecological relevance of laboratory bioassays. The objectives of this study were to develop an in situ test chamber and respective test protocols suitable for ecotoxicity testing with zooplankton and to evaluate the use of laboratory protocols (water column and solid phase) by comparing results obtained under controlled conditions with in situ results at an aquatic system receiving acid mine drainage. At the most contaminated stations and at the reference stations, good agreement was found between in situ and classical setting. At intermediate stations, in situ toxicity was generally higher than that in classical tests. Sample collection and preservation probably altered actual toxicity, thus emphasizing the need for caution in estimating or extrapolating field effects from laboratory results.

Pereira, A.M.M; Da Maia Soares, A.M.V.; Goncalves, F.; Ribeiro, R.

1999-09-01

174

The environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin disturbs the establishment and maintenance of cell polarity in preimplantation rat embryos.  

PubMed

Maternal exposure to the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces a variety of defects in compaction-stage embryos, including monopolar spindle formation, errors in chromosome segregation, and fragmentation resulting from aberrant cytokinesis. In this study, we investigated the possibility that a failure in centrosome duplication, separation, or positioning within blastomeres might underlie the observed effects of TCDD on early embryos. The subcellular localization of the centrosomal marker TUBG1 was analyzed in preimplantation embryos collected from female rats exposed to either chronic (50 ng kg(-1) wk(-1) for 3 wk) or acute (50 ng/kg or 1 microg/kg at proestrus) doses of TCDD. In treated embryos, interphase TUBG1 foci were more abundant and cortically displaced when compared to those in controls. At prophase, some blastomeres exhibited a single large perinuclear TUBG1 aggregate, suggesting a failure in centrosome duplication or separation. Furthermore, the presence of monopolar spindles at metaphase was confirmed by the localization of TUBG1 to the single spindle pole. Therefore, the misregulation of centrosome number and localization, as indicated by TUBG1 staining, may contribute to errors in chromosome segregation and cytokinesis in embryos following maternal TCDD exposure. PMID:20089886

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

2010-01-20

175

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

SciTech Connect

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

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

1995-07-01

176

Toxicity testing in environmental monitoring: the role of enzymatic biosensors.  

PubMed

Biological toxicity testing is a rapidly expanding field involving numerous bioanalytical techniques. The enzymatic biosensors are valuable screening tools to identify pollutants and/or toxic agents in the environment and/or in food matrices, thus representing a valid alternative to animal testing in analytical toxicology. Inhibition based biosensors here presented have been proved to represent alternative assays for the toxicity evaluation of warfare agents and endocrine disrupting chemicals as well as algal toxins (phycotoxins) in the contamined sea foods (mainly clams and other mollusks). Results obtained by inhibition studies performed by means of several enzymatic biosensors indicate the reliability of the proposed method and the possibility to extend such an experimental approach to other toxicants as a simple, rapid and cheap biotest, to be used easily also "on the spot". PMID:12046232

Botrč, F; Podestŕ, E; Silvestrini, B; Botrč, C

2001-01-01

177

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 ...

178

Economical test methods for developmental neurobehavioral toxicity.  

PubMed Central

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

Bignami, G

1996-01-01

179

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

SciTech Connect

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.

Specht, W.L. [Westinghouse Savannah River Company, Aiken, SC (United States)

1997-07-01

180

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

PubMed

Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC50s for 14 and 28 days were 5311 and 5395 microgPb g(-1)soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 microgPb g(-1)soil. The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 microg g(-1) soil accumulated lead at a faster rate (3.16 microg Pb g(-1)tissue day(-1)) than those in the 3000 microg g(-1) soil (2.21 microg Pb g(-1)tissue day(-1)). The third experiment was a timed experiment with worms cultivated in soil containing 7000 microgPb g(-1)soil. Soil and lead nitrate solution were mixed and stored at 20 degrees C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration time of artificially amended Pb-bearing soils increases the bioavailability of Pb decreases. Thus addition of worms shortly after addition of Pb to soils may result in the over-estimate of Pb toxicity to worms. The current OECD acute worm toxicity test fails to take these two phenomena into account thereby reducing the environmental relevance of the contaminant toxicities it is used to calculate. PMID:12475061

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

2003-01-01

181

Limited Toxicity and Mutagenicity Testing of Five Unicharge Propellant Compounds.  

National Technical Information Service (NTIS)

Bis-(2,2-dinitropropyl) acetal/formal (-50/50'mixture) diphenyl amine stabilizer (BDNPA/F+/-DPA) were tested for oral toxicity. Groups of ten mice per dose level were fasted and administered the test article orally by gavage. Animals were observed for cli...

V. B. Ciofalo V. T. Mallory

1992-01-01

182

Acute systemic toxicity—prospects for tiered testing strategies  

Microsoft Academic Search

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

P. A. Botham

2004-01-01

183

PROPOSED TEST PROTOCOL TO DETERMINE TOXICANT LEACHING INTO POTABLE WATER  

EPA Science Inventory

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

184

Alternative methods in toxicology tests: In vitro toxicity  

Microsoft Academic Search

Toxicity testing is required for new chemicals being introduced onto the market. The use of animals in evaluating chemical safety is costly and time consuming. Furthermore, there is the ethical need to develope alternative methods to reduce the required number of animals. The newinvitro assays offer numerous advantages such as speed, reproducibility and control of test conditions, and increased sensitivity.

S. Cinelli; A. Falezza; C. Meli; P. Ciliutti; J. A. Vericat

1991-01-01

185

Using Transgenic Caenorhabditis elegans in Soil Toxicity Testing  

Microsoft Academic Search

Soil bioassays are important tools for evaluating toxicological effects within the terrestrial environment. The American Society for Testing and Materials E2172-01 Standard Guide outlines a method for conducting laboratory soil toxicity tests using the nematode Caenorhabditis elegans. This method is an efficient tool for extracting C. elegans from soil samples and can be carried out after a 24-h exposure period

Amber L. Graves; Windy A. Boyd; Phillip L. Williams

2005-01-01

186

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...

187

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...

188

Knockdown of AHR1A but not AHR1B exacerbates PAH and PCB-126 toxicity in zebrafish (Danio rerio) embryos.  

PubMed

Various environmental contaminants are known agonists for the aryl hydrocarbon receptor (AHR), which is highly conserved across vertebrate species. Due to gene duplication events before and after the divergence of ray- and lobe-finned fishes, many teleosts have multiple AHR isoforms. The zebrafish (Danio rerio) has three identified AHRs: AHR1A and AHR1B, the roles of which are not yet well elucidated, and AHR2, which has been shown to mediate the toxicity of various anthropogenic compounds including dioxins, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). In this study, we sought to explore the role of the two AHR1 isoforms in PAH- and PCB-induced toxicity in zebrafish embryos utilizing morpholino gene knockdown of the AHR isoforms. Knockdown of AHR1B did not affect the toxicity of PAH mixtures or PCB-126, whereas knockdown of AHR1A exacerbated the cardiac toxicity caused by PAH mixtures and PCB-126. Knockdown of AHR1A did not impact the mRNA expression of CYP1A, CYP1B1, and CYP1C1 in exposed embryos, but it did result in increased CYP1 activity in exposed embryos. As has been shown previously, knockdown of AHR2 resulted in protection from PAH- and PCB-induced cardiac deformities and prevented CYP1 enzyme activity in exposed embryos. Co-knockdown of AHR1A and AHR2 resulted in an intermediate response compared to knockdown of AHR1A and AHR2 individually; co-knockdown did not exacerbate nor protect from PAH-induced deformities and embryos exhibited an intermediate CYP1 enzyme activity response. In contrast, co-knockdown of AHR1A and AHR2 did protect from PCB-126-induced deformities. These results suggest that AHR1A is not a nonfunctional receptor as previously thought and may play a role in the normal physiology of zebrafish during development and/or the toxicity of environmental contaminants in early life stages. PMID:24084256

Garner, Lindsey V T; Brown, Daniel R; Di Giulio, Richard T

2013-09-16

189

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

PubMed

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

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

2011-07-18

190

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

SciTech Connect

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.

Park, Margriet V.D.Z. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment, 3720 BA, Bilthoven (Netherlands); Department of Health Risk Analysis and Toxicology, Maastricht University, 6200 MD Maastricht (Netherlands)], E-mail: Margriet.Park@rivm.nl; Annema, Wijtske [Laboratory for Health Protection Research, National Institute for Public Health and the Environment, 3720 BA, Bilthoven (Netherlands); Salvati, Anna; Lesniak, Anna [Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4 (Ireland); Elsaesser, Andreas; Barnes, Clifford; McKerr, George; Howard, C. Vyvyan [Centre for Molecular Bioscience, University of Ulster, Coleraine, BT52 1SA (United Kingdom); Lynch, Iseult; Dawson, Kenneth A. [Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4 (Ireland); Piersma, Aldert H. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment, 3720 BA, Bilthoven (Netherlands); Institute for Risk Assessment Sciences, University of Utrecht, 3508 TD, Utrecht (Netherlands); Jong, Wim H. de [Laboratory for Health Protection Research, National Institute for Public Health and the Environment, 3720 BA, Bilthoven (Netherlands)

2009-10-01

191

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

SciTech Connect

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

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

1987-08-01

192

Using toxicity testing to evaluate electrochemical reactor operations.  

PubMed

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

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

2012-02-06

193

Baker's yeast assay procedure for testing heavy metal toxicity  

SciTech Connect

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

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

1984-01-01

194

Biologically relevant exposure science for 21st century toxicity testing.  

PubMed

High visibility efforts in toxicity testing and computational toxicology including the recent National Research Council of the National Academies (NRC) report, Toxicity Testing in the 21st Century: A Vision and Strategy (NRC, 2007a), raise important research questions and opportunities for the field of exposure science. The authors of the National Academies report (NRC, 2007a) emphasize that population-based data and human exposure information are required at each step of their vision for toxicity testing and that these data will continue to play a critical role in both guiding development and use of the toxicity information. In fact, state-of-the-art exposure science is essential for translation of toxicity data to assess potential for risk to individuals and populations and to inform public health decisions. As we move forward to implement the NRC vision, a transformational change in exposure science is required. Application of a fresh perspective and novel techniques to capture critical determinants at biologically motivated resolution for translation from controlled in vitro systems to the open multifactorial system of real-world human-environment interaction will be critical. Development of an exposure ontology and knowledge base will facilitate extension of network analysis to the individual and population for translating toxicity information and assessing health risk. Such a sea change in exposure science is required to incorporate consideration of lifestage, genetic susceptibility, and interaction of nonchemical stressors for holistic assessment of risk factors associated with complex environmental disease. A new generation of scientific tools has emerged to rapidly measure signals from cells, tissues, and organisms following exposure to chemicals. Investment in 21st century exposure science is now required to fully realize the potential of the NRC vision for toxicity testing. PMID:19602574

Hubal, Elaine A Cohen

2009-07-14

195

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...

196

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....

197

An in-vitro toxicity testing - a reliable alternative to toxicity testing by reduction, replacement and refinement of animals  

Microsoft Academic Search

In the past few years, many in vitro methods for animal toxicity testing have been developed, validated, as a alternative to whole animal tests and it gained regulatory acceptance due to ethical and scientific concerns regarding the use of animals. These alternative methods are developed and validated using Reduction, Replacement and Refinement - 3Rs approach. A range of non animal

M. Bhanushali; V. Bagale; A. Shirode; Y. Joshi; V. Kadam

2010-01-01

198

EUGENIC SELECTION BENEFITS EMBRYOS.  

PubMed

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

Walker, Mark

2012-07-29

199

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

PubMed

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

Martin, Pauline L; Weinbauer, Gerhard F

2010-10-06

200

Resolving some practical questions about Daphnia acute toxicity tests  

SciTech Connect

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

Barera, Y.; Adams, W.J.

1981-10-01

201

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

Microsoft Academic Search

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

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

1999-01-01

202

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

PubMed

Urban stormwater runoff is composed of a mixture of components, including polycyclic aromatic hydrocarbons, metals, deicing agents, and many others. The fate of these chemicals is often in stormwater detention ponds that are used by amphibians for breeding. Among aquatic organisms, the toxic mechanism for many metals involves interference with active Na(+) and Cl(-) uptake. Addition of cations has been shown to reduce the toxicity of metals among some aquatic organisms through competitive inhibition, but no studies have investigated the interaction between NaCl and Cu among amphibian embryos and larvae. To determine the degree to which NaCl may ameliorate the toxicity of Cu to amphibian embryos and larvae, the authors exposed Hyla chrysoscelis (Cope's gray treefrogs) and Rana (Lithobates) clamitans (green frogs) to seven levels of Cu and NaCl in fully factorial experiments. When exposure was in artificial hard water, Cu was highly toxic to both species (96-h median lethal concentration [LC50] of 44.7 µg/L and 162.6 µg/L for H. chrysoscelis and R. clamitans, respectively). However, approximately 500 mg/L of NaCl eliminated Cu toxicity over the range of Cu concentrations used in the experiments (maximum 150 µg Cu/L for H. chrysoscelis and 325 µg Cu/L for R. clamitans). The current results suggest that NaCl is likely responsible for the toxic effects of NaCl and metal mixtures that might be typical of runoff from road surfaces in northern latitudes. PMID:22278879

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

2012-04-01

203

Tissue Morphology and Cell Impedance Based Biosensors for Toxicity Testing  

Microsoft Academic Search

In vitro neurotoxicity testing and toxicity effect quantification plays an important role in many disciplines of biomedicine as an alternative to in vivo methods. The principle of the majority of in vitro methods corresponds to the basic concept of biosensors, i.e. measured quantity is by means of biological sensing element transformed to physical quantity easily measurable by electrical methods of

S. Dado

2009-01-01

204

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...

205

Acute Toxicity Tests Re: Lubricating Oil Base Stocks.  

National Technical Information Service (NTIS)

In accordance with API policy, I am enclosing seven drafts final reports from Elars Bioresearch Laboratories on acute toxicity tests with the following lubricating oil base stocks: API Sample 78-9 - 70 SUS/100 deg F Paraffinic Oil; API Sample 78-10 - 150 ...

1982-01-01

206

21 CFR 620.5 - Mouse toxicity test.  

Code of Federal Regulations, 2010 CFR

...Vaccine] [Sec. 620.5 - Mouse toxicity test.] 21 FOOD AND DRUGS 7 1996-04-01...A group of no less than 10 mice, each mouse weighing 14 to 16 grams, shall have free access to food and water for no less than...

1996-04-01

207

21 CFR 620.34 - Mouse toxicity test.  

Code of Federal Regulations, 2010 CFR

...Vaccine] [Sec. 620.34 - Mouse toxicity test.] 21 FOOD AND DRUGS 7 1996-04-01...than 10 and no more than 40 mice, each mouse weighing 14 to 16 grams, shall have free access to food and water at least 2...

1996-04-01

208

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

Microsoft Academic Search

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

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

1996-01-01

209

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

PubMed

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

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

210

The toxicity of mercuric chloride and methylmercuric chloride to Fundulus heteroclitus embryos in relation to exposure conditions  

Microsoft Academic Search

Synopsis Embryos in specific stage of the estuarine teleost, Fundulus heteroclitus, were exposed to mercuric chloride (MC) and methylmercuric chloride (MMC) under several distinct treatment conditions. Four-eight cell stage eggs (0-day old) were exposed for 4 days (continuous), 2 days and one day to each mercury compound. One-day old (mid-blastula), 2-day old (mid-neurula) and 5-day old (beating heart) embryos were

John R. Sharp; Jerry M. Neff

1982-01-01

211

EP-toxicity testing of mercury removal resin grout  

SciTech Connect

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.

Mersman, K.E.

1984-07-18

212

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

Microsoft Academic Search

The initiative by the River Purification Boards (RPBs), National Rivers Authority (NRA) and Her Majesty's Inspectorate of Pollution (HMIP) to control certain complex and toxic effluent discharges by direct toxicity assessment places great emphasis on the use of aquatic toxicity tests. Like all biological and analytical measurements, determinations of toxicity exhibit variability. When setting ‘Toxicity-based Consents’ (TBCs) and monitoring for

Paul Whitehouse; Mark Crane; C. John Redshaw; Craig Turner

1996-01-01

213

Toxicity of Inorganic Compounds in the Spirotox Test: A Miniaturized Version of the Spirostomum ambiguum Test  

Microsoft Academic Search

.   The Spirostomum ambiguum toxicity test has been intensively studied in the Department of Environmental Health Sciences, Warsaw University of Medicine\\u000a for the last 5 years. The purpose of the present work was to develop and evaluate a miniaturized microplate version of the\\u000a test, called the Spirotox test, and to estimate the toxicity of selected inorganic compounds to the Spirostomum

J. Sawicki

1998-01-01

214

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

Code of Federal Regulations, 2013 CFR

...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) ...intended to meet testing requirements of the Toxic Substances Control Act (TSCA) (15 U...Office of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized...

2013-07-01

215

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

SciTech Connect

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

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

1993-03-01

216

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

National Technical Information Service (NTIS)

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

S. P. Wang J. T. Grayston

1967-01-01

217

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

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 temporal trends of TCDD-induced AHRs and CYP1A expression, and developmental toxicities, the highest expression of rsAHR2 and CYP1A mRNA were detected prior to the appearance of maximal incidence of TCDD toxic manifestations. These results suggest that rsAHR2 may be dominantly involved in the transcriptional regulation of CYP1A, and several TCDD defects are dependent on the alteration of rsAHR2 and/or rsAHR2-CYP1A signaling pathway that is controlled through their expression levels. PMID:16987556

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

2006-09-20

218

COMPARISON AND EVALUATION OF FIELD AND LABORATORY TOXICITY TESTS WITH FENVALERATE ON AN ESTUARINE CRUSTACEAN  

EPA Science Inventory

A combination of laboratory toxicity tests was conducted on the grass shrimp, Palaemonetes pugio. est results were compared with field toxicity tests to evaluate the usefulness of laboratory testing in estimating mortality from fenvalerate exposure associated with agricultural ru...

219

Antioxidant, Antimicrobial Activity and Toxicity Test of Pilea microphylla  

PubMed Central

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

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

2010-01-01

220

In situ toxicity testing with locally collected Daphnia  

SciTech Connect

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

Snyder-Conn, E.

1993-07-01

221

Acute and early life stage toxicity of industrial effluent on Japanese medaka ( Oryzias latipes)  

Microsoft Academic Search

To develop the whole effluent toxicity testing methods (WET), embryo larval stage toxicity test using Japanese medaka (Oryzias latipes) was conducted to evaluate an effluent from a banknote printing plant (BPP). The method is based on acute toxicity using endpoint of 96-h larval morality and on chronic toxicity using endpoints such as the time to hatch, hatching success, deformity, growth

Jinmiao Zha; Zijian Wang

2006-01-01

222

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

SciTech Connect

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.

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

2000-01-01

223

Deciding how many embryos to transfer after in vitro fertilisation: Development and pilot test of a decision aid  

Microsoft Academic Search

ObjectiveWhen deciding how many embryos to transfer during in vitro fertilisation (IVF), clinicians and patients have to balance optimizing the chance of pregnancy against preventing multiple pregnancies and the associated complications. This paper describes the development and pilot test of a patient decision aid (DA) for this purpose.

Arno M. van Peperstraten; Rosella P. M. G. Hermens; Willianne L. D. M. Nelen; Peep F. M. Stalmeier; Alex M. M. Wetzels; Pettie H. M. Maas; Jan A. M. Kremer; Richard P. T. M. Grol

2010-01-01

224

Toxicity of the Alternaria metabolites alternariol, alternariol methyl ether, altenuene, and tenuazonic acid in the chicken embryo assay.  

PubMed Central

The effects in the chicken embryo assay of four Alternaria metabolites (alternariol [AOH], alternariol methyl ether [AME], altenuene [ALT], and tenuazonic acid [TA]) were investigated. Administered to 7-day-old chicken embryos by yolk sac injection, AOH, AME, and ALT caused no mortality or teratogenic effect at doses up to 1,000, 500, and 1,000 micrograms per egg, respectively. TA exhibited a calculated 50% lethal dose of 548 micrograms per egg, with no teratogenic effect observed at either lethal or sublethal doses.

Griffin, G F; Chu, F S

1983-01-01

225

Toxicogenomic Responses of Zebrafish Embryos/Larvae to Tris(1,3-dichloro-2-propyl) Phosphate (TDCPP) Reveal Possible Molecular Mechanisms of Developmental Toxicity.  

PubMed

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

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

2013-08-27

226

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

SciTech Connect

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

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

1996-10-01

227

Field assessments in conjunction with whole effluent toxicity testing  

SciTech Connect

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

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

2000-01-01

228

A category approach to predicting the developmental (neuro) toxicity of organotin compounds: The value of the zebrafish (Danio rerio) embryotoxicity test (ZET).  

PubMed

Zebrafish embryos were exposed to different organotin compounds during very early development (<100h post fertilization). Morphology, histopathology and swimming activity (in a motor activity test) were the endpoints analyzed. DBTC was, by far, the most embryotoxic compound at all time points and endpoints studied. In fact, we observed a clear concordance between the effects observed in our zebrafish embryo model, and those observed with these compounds in full rodent in vivo studies. All organotin compounds classified as developmental (neuro) toxicants in vivo, were correctly classified in the present assay. Together, our results support the ZET model as a valuable tool for providing biological verification for a grouping and a read-across approach to developmental (neuro) toxicity. PMID:23796951

Beker van Woudenberg, Anna; Wolterbeek, André; Te Brake, Lindsey; Snel, Cor; Menke, Aswin; Rubingh, Carina; de Groot, Didima; Kroese, Dinant

2013-06-21

229

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

PubMed

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 when they occur. PMID:23400869

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

2013-03-29

230

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

Microsoft Academic Search

With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U.S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal usage by transitioning from current expensive and lengthy in vivo testing with qualitative

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

2010-01-01

231

Vitamin C and vitamin E supplementation reduce oxidative stress–induced embryo toxicity and improve the blastocyst development rate  

Microsoft Academic Search

ObjectiveTo evaluate the adverse effects of exogenously induced reactive oxygen species (ROS) on mouse embryo development by using the 12-phorbol 13-myristate acetate (PMA)–activated leukocyte model as a source of ROS, and to examine the protective effect of antioxidant supplementation (vitamin C and vitamin E).

Xia Wang; Tommaso Falcone; Marjan Attaran; Jeffrey M Goldberg; Ashok Agarwal; Rakesh K Sharma

2002-01-01

232

Bioavailability of fluoranthene in freshwater sediment toxicity tests  

SciTech Connect

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.

Suedel, B.C.; Rodgers, J.H. Jr. (Univ. of Mississippi, University (United States)); Clifford, P.A. (EA Engineering Science and Technology, Inc., Sparks, MD (United States))

1993-01-01

233

Chronic toxicity of the azaarene quinoline, a synthetic fuel component, to the pond snail Physa gyrina  

Microsoft Academic Search

The azaarene quinoline was tested for chronic toxicity to embryos of the pulmonate snail Physa gyrina. Toxicity criteria were effects on embryogenesis, embryo survival, time to hatching, hatching success, and posthatching survival. Of the controls, 91% hatched, compared with 99, 78, and 5% exposed to 12.5, 25, and 50 mg\\/L of quinoline, respectively. No eggs hatched at or above 100

Raymond E. Millemann; Daniel S. Ehrenberg

1982-01-01

234

Current and future needs for developmental toxicity testing.  

PubMed

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

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

2011-09-15

235

A Comparison of Sediment Toxicity Test Methods at Three Great Lake Areas of Concern  

Microsoft Academic Search

The significance of sediment contamination is often evaluated using sediment toxicity (bioassay) testing. There are relatively few “standardized” test methods for evaluating sediments. Popular sediment toxicity methods examine the extractable water (elutriate), interstitial water, or whole (bulk) sediment phases using test species spanning the aquatic food chain from bacteria to fish. The current study was designed to evaluate which toxicity

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

1996-01-01

236

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...

237

Using the Caenorhabditis elegans soil toxicity test to identify factors affecting toxicity of four metal ions in intact soil  

Microsoft Academic Search

A previously developed soil toxicity test for rapidly determining the toxicity of chemicals to the soil-dwelling nematode Caenorhabditis elegans (Donkin and Dusenbery, 1993) was used to measure the toxicity of four metals (Zn2+, Cd2+, Cu2+, and Pb2+) added to four soils common to the southeastern United States. Nematode survival after a 24-hour exposure in the presence of a bacterial food

Steven G. Donkin; David B. Dusenbery

1994-01-01

238

Trend tests for proportional responses in developmental toxicity experiments  

SciTech Connect

The data from developmental toxicity experiments usually are very difficult to analyze statistically because of the lack of independence among littermates and the random nature of the litter size. Only a few of the models that have been proposed in the literature have accounted for both of these features. One of the models proposed by Van Ryzin is invoked to construct a test of trend (dose response). The construction is achieved via a statistical technique called isotonic regression, which is applied to the moment estimators derived by Van Ryzin. The trend test based on isotonic regression is relatively straightforward to calculate, and when the number of dose groups (including control) is four or less, the significance of the observed result is easily determined. An example, in which fetolethality is the end point of interest, demonstrates the test.

Chinchilli, V.M.; Clark, B.C. (Virginia Commonwealth Univ., Richmond (USA))

1989-02-01

239

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...

240

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

PubMed

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 collected GV or MII oocytes to sugar concentrations between 0.5 and 1.0 M, for up to 10 min had no significant effect on the proportion which subsequently formed two cells. We conclude that added sugars do contribute to a solutions overall vitrification properties, and their properties should be taken into consideration when vitrification solutions are being designed or modified. PMID:10191035

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

1999-03-01

241

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

PubMed

Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of light-saturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures limited by either nitrogen or phosphorus. The sensitivity of the photosynthesis tests were compared to standardized growth tests applied to the same species and toxicants. For Cu and S. costatum the photosynthesis test was up to 300 times more sensitive at light saturation than at light limitation. For the remaining photosynthesis tests no dependence on light condition were found. The photosynthesis tests with Cu and S. costatum were up to 10 times as sensitive as the growth test and most sensitive when the algae were obtained from a phosphate-limited chemostate. For the other photosynthesis tests no dependence on the growth condition were found, and the photosynthesis tests were as sensitive as the growth test. Photosynthesis tests offer an alternative to growth tests for hazard assessment of toxicants. PMID:10629275

Petersen, S; Kusk, K O

2000-02-01

242

Non-animal methodologies within biomedical research and toxicity testing.  

PubMed

Laboratory animal models are limited by scientific constraints on human applicability, and increasing regulatory restrictions, driven by social concerns. Reliance on laboratory animals also incurs marked - and in some cases, prohibitive - logistical challenges, within high-throughput chemical testing programmes, such as those currently underway within Europe and the US. However, a range of non-animal methodologies is available within biomedical research and toxicity testing. These include: mechanisms to enhance the sharing and assessment of existing data prior to conducting further studies, and physicochemical evaluation and computerised modelling, including the use of structure-activity relationships and expert systems. Minimally-sentient animals from lower phylogenetic orders or early developmental vertebral stages may be used, as well as microorganisms and higher plants. A variety of tissue cultures, including immortalised cell lines, embryonic and adult stem cells, and organotypic cultures, are also available. In vitro assays utilising bacterial, yeast, protozoal, mammalian or human cell cultures exist for a wide range of toxic and other endpoints. These may be static or perfused, and may be used individually, or combined within test batteries. Human hepatocyte cultures and metabolic activation systems offer potential assessment of metabolite activity and organ-organ interaction. Microarray technology may allow genetic expression profiling, increasing the speed of toxin detection, well prior to more invasive endpoints. Enhanced human clinical trials utilising micro- dosing, staggered dosing, and more representative study populations and durations, as well as surrogate human tissues, advanced imaging modalities and human epidemiological, sociological and psycho- logical studies, may increase our understanding of illness aetiology and pathogenesis, and facilitate the development of safe and effective pharmacologic interventions. Particularly when human tissues are used, non-animal models may generate faster, cheaper results, more reliably predictive for humans, whilst yielding greater insights into human biochemical processes. Greater commitment to their development and implementation is necessary, however, to efficiently meet the needs of high-throughput chemical testing programmes, important emerging testing needs, and the ongoing development of human clinical interventions. PMID:18841317

Knight, Andrew

2008-01-01

243

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

Microsoft Academic Search

In a series of experiments the toxicity of lead to worms in soil was determined following the draft OECD earthworm reproduction toxicity protocol except that lead was added as solid lead nitrate, carbonate and sulphide rather than as lead nitrate solution as would normally be the case. The compounds were added to the test soil to give lead concentrations of

Nicola A Davies; Mark E Hodson; Stuart Black

2003-01-01

244

CELLULAR TOXICITY IN CHINESE HAMSTER OVARY CELL CULTURES. 2. A STATISTICAL APPRAISAL OF SENSITIVITY WITH THE RABBIT ALVEOLAR MACROPHAGE, SYRIAN HAMSTER EMBRYO, BALB 3T3 MOUSE, AND HUMAN NEONATAL FIBROBLAST CELL SYSTEMS  

EPA Science Inventory

Chinese hamster ovary, rabbit alveolar macrophage, Syrian Hamster embryo, mouse, and human neonatal fibroblast cells were employed in a statistical evaluation of the relative sensitivity of the cells to toxic substances. The cells were exposed to 1,2,4-trichlorobenzene, 2,4-dimet...

245

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

PubMed

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

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

2012-02-21

246

Use of multidimensional scaling in the selection of wastewater toxicity test battery components  

Microsoft Academic Search

In aquatic toxicity testing, no single test species is sensitive to all toxicants. Therefore, test batteries consisting of several individual assays are becoming more common. The organisms in a test battery should be representative of the entire system of interest. The results of the assays should be complementary to other components in the test battery to avoid redundancy. With the

Shijin Ren; Paul D. Frymier

2003-01-01

247

Evaluation of a phytoplankton toxicity test for water pollution assessment and control  

Microsoft Academic Search

A suggested standard test protocol for the short term14C assimilation algal toxicity test method (photosynthesis inhibition test) has been evaluated with natural phytoplankton and cultures of the marine diatomSkeletonema costatum. A number of test technical factors as well as the variability in the sensitivity of natural phytoplankton have been investigated, using potassium dichromate as a reference toxicant in all tests.

Kresten Ole Kusk; Niels Nyholm

1991-01-01

248

Hazard Evaluation of Soil Contaminants with Aquatic Animals and Plant Toxicity Tests  

Microsoft Academic Search

Deleterious effects upon the biota should be one of the principal characteristics used to perform the initial assessment of contamination and the acceptable level of clean-up at hazardous waste sites. Acute toxicity tests are probably the best means for conducting rapid preliminary assessment of distribution and extent of toxic conditions at a site. On the other hand acute toxicity tests

A. Ramanathan; S. L. Burks

1996-01-01

249

40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B...IX Appendix IX to Part 268âExtraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method...

2013-07-01

250

Toxicity testing of organic chemicals in groundwater polluted with landfill leachate  

SciTech Connect

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.

Baun, A.; Kloeft, L.; Bjerg, P.L.; Nyholm, N.

1999-09-01

251

Evaluation of municipal waste incinerator fly ash toxicity and the role of cadmium by two aquatic toxicity tests  

SciTech Connect

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.

Kaneko, Hidehiro [Yamanashi Univ., Kofu, Yamanashi (Japan). Dept. of Civil and Environmental Engineering

1996-12-31

252

Acute toxicity tests on three species of the genus Lecane (Rotifera: Monogononta)  

Microsoft Academic Search

Three rotifer species, Lecane hamataL. luna, and L. quadridentata, were submitted to acute toxicity tests to compare their susceptibility to 11 toxicants. In acute tests with 48-h exposure of neonates of less than 24 h old, copper was most toxic with LC50 values in the range of 0.06–0.33 mg l-1, while acetone was the least toxic with LC50 values in

Ignacio Alejandro Pérez-Legaspi; Roberto Rico-Martínez

2001-01-01

253

Aquatic toxicity testing for multicomponent compounds with special reference to preparation of test solution  

SciTech Connect

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.

Tadokoro, H.; Maeda, M.; Kawashima, Y.; Kitano, M.; Hwang, D.F.; Yoshida, T. (Chemical Biotesting Center, Chemicals Inspection and Testing Institute, Tokyo (Japan))

1991-02-01

254

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

PubMed

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

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

2013-03-19

255

Photosynthesis Tests as an Alternative to Growth Tests for Hazard Assessment of Toxicant  

Microsoft Academic Search

.   Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of light-saturated\\u000a and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures limited by either nitrogen or phosphorus.\\u000a The sensitivity of the photosynthesis tests were compared to standardized growth tests applied to the

S. Petersen; K. O. Kusk

2000-01-01

256

Toxicity assessment for chlorpyrifos-contaminated soil with three different earthworm test methods  

Microsoft Academic Search

Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration

Shi-ping ZHOU; Chang-qun DUAN; Hui FU; Yu-hui CHEN; Xue-hua WANG; Ze-fen YU

2007-01-01

257

Hepatotoxicity and subchronic toxicity tests of Morinda citrifolia (noni) fruit.  

PubMed

Morinda citrifolia (noni) fruit juice has been approved as a safe food in many nations. A few cases of hepatitis in people who had been drinking noni juice have been reported, even though no causal link could be established between the liver injury and ingestion of the juice. To more fully evaluate the hepatotoxic potential of noni fruit juice, in vitro hepatotoxicity tests were conducted in human liver cells, HepG2 cell line. A subchronic oral toxicity test of noni fruit was also performed in Sprague-Dawley (SD) rats to provide benchmark data for understanding the safety of noni juice, without the potential confounding variables associated with many commercial noni juice products. Freeze-dried filtered noni fruit puree did not decrease HepG2 cell viability or induce neutral lipid accumulation and phospholipidosis. There were no histopathological changes or evidence of dose-responses in hematological and clinical chemistry measurements, including liver function tests. The no-observed-adverse-effect level (NOAEL) for freeze-dried noni fruit puree is greater than 6.86 g/kg body weight, equivalent to approximately 90 ml of noni fruit juice/kg. These findings corroborate previous conclusions that consumption of noni fruit juice is unlikely to induce adverse liver effects. PMID:19797868

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

2009-10-01

258

Simple Diagnostic Tests to Detect Toxic Alcohol Intoxications  

PubMed Central

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.

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

2008-01-01

259

Reproducibility of a life-cycle toxicity test with Daphnia magna  

SciTech Connect

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

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

1981-01-01

260

Chlorinated benzo-1,2-quinones: an example of chemical transformation of toxicants during tests with aquatic organisms  

SciTech Connect

An analytical procedure specific for chlorinated benzo-1,2-quinones has been developed to examine the stability of these compounds under conditions used for investigating their toxicity to aquatic organisms. Solutions of the compounds in a number of organic solvents were unstable in the light, and addition of acetone solutions to water brought about rapid decomposition of the chloroquinones which had half-lives less than 0.5 hr: the corresponding chlorocatechols were the principal products. The kinetics of decomposition of tetrachlorobenzo-1,2-quinone in aqueous solutions were studied in detail and showed the formation of tetrachlorocatechol, 2,5-dichloro-3,6-dihydroxybenzo-1,4-quinone, 1,2,3-trihydroxy-4,5,6-trichlorobenzene, 1,2,4-trihydroxy-3,5,6-trichlorobenzene, dichloromaleic acid, and a trichlorocyclopentendione. In organic solvents in the light, 3,4,5-trichlorobenzo-1,2-quinone underwent a dismutation reaction with formation of 3,4,5-trichloro- and tetrachlorocatechol; in a comparable reaction, 4,5-dichlorobenzo-1,2-quinone formed 4,5-dichlorocatechol and 3,4,5-trichlorocatechol. The toxicity of aqueous solutions prepared by dilution of freshly prepared acetone solutions of tetrachlorobenzo-1,2-quinone was examined in the zebra fish embryo/larvae test, and it was found that the threshold toxic concentration could be accounted for entirely by the analytically established concentration of tetrachlorocatechol produced as a chemical transformation product. It is concluded that in toxicological examination of reactive compounds, exposure to the toxicant should be assessed from concentrations analytically determined during the experiments and that attention be directed to both the nature and the toxicity of the transformation products.

Remberger, M.; Hynning, P.A.; Neilson, A.H. (Swedish Environmental Research Institute, Stockholm (Sweden))

1991-12-01

261

Chlorinated benzo-1,2-quinones: an example of chemical transformation of toxicants during tests with aquatic organisms.  

PubMed

An analytical procedure specific for chlorinated benzo-1,2-quinones has been developed to examine the stability of these compounds under conditions used for investigating their toxicity to aquatic organisms. Solutions of the compounds in a number of organic solvents were unstable in the light, and addition of acetone solutions to water brought about rapid decomposition of the chloroquinones which had half-lives less than 0.5 hr: the corresponding chlorocatechols were the principal products. The kinetics of decomposition of tetrachlorobenzo-1,2-quinone in aqueous solutions were studied in detail and showed the formation of tetrachlorocatechol, 2,5-dichloro-3,6-dihydroxybenzo-1,4-quinone, 1,2,3-trihydroxy-4,5,6-trichlorobenzene, 1,2,4-trihydroxy-3,5,6-trichlorobenzene, dichloromaleic acid, and a trichlorocyclopentendione. In organic solvents in the light, 3,4,5-trichlorobenzo-1,2-quinone underwent a dismutation reaction with formation of 3,4,5-trichloro- and tetrachlorocatechol; in a comparable reaction, 4,5-dichlorobenzo-1,2-quinone formed 4,5-dichlorocatechol and 3,4,5-trichlorocatechol. The toxicity of aqueous solutions prepared by dilution of freshly prepared acetone solutions of tetrachlorobenzo-1,2-quinone was examined in the zebra fish embryo/larvae test, and it was found that the threshold toxic concentration could be accounted for entirely by the analytically established concentration of tetrachlorocatechol produced as a chemical transformation product. It is concluded that in toxicological examination of reactive compounds, exposure to the toxicant should be assessed from concentrations analytically determined during the experiments and that attention be directed to both the nature and the toxicity of the transformation products. PMID:1844397

Remberger, M; Hynning, P A; Neilson, A H

1991-12-01

262

Toxicity testing of wastewater and sewage sludge by biosensors, bioassays and chemical analysis  

Microsoft Academic Search

Toxicity testing has grown steadily in recent years, being a useful tool in environmental risk assessment. This review highlights different bioassays and recently developed biosensors based on acute toxicity measurements. Emphasis is placed on the use of combined approaches involving chemical analysis for the characterization and identification of complex toxic wastewater effluents and sewage sludge. Fractionation schemes that combine sample

Marinella Farré; Damiŕ Barceló

2003-01-01

263

Toxicity Testing of Soil Samples from J-Field, Aberdeen Proving Ground, MD.  

National Technical Information Service (NTIS)

Soil samples from the toxic burning pits, an area adjacent to the toxic burning pits, white phosphorus pits, and riot control pits were tested for their toxicity to lettuce and earthworms as part of an ecological risk assessment of J-Field. Standardized s...

C. T. Phillips R. T. Checkal

1995-01-01

264

MARINE COMPLEX EFFLUENT TOXICITY PROGRAM: TEST SENSITIVITY, REPEATAELITY AND RELEVANCE TO RECEIVING WATER TOXICITY  

EPA Science Inventory

In March 1984, the U.S. Environmental Protection Agency (EPA) issued a significant change in procedures regulating toxic materials in effluents through the National Pollutant Discharge Elimination System (NPDES). Concurrent with this toxicity-based effluent control policy, the EP...

265

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

SciTech Connect

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 financial support associated with maintaining the cultures until testing is needed. The purpose of this document is to provide guidance on how to establish a laboratory culture of D. ambigua so that a culture can be restarted when needed.

Specht, Winona L.

2005-07-01

266

Sensitivity of submersed freshwater macrophytes and endpoints in laboratory toxicity tests  

Microsoft Academic Search

The toxicological sensitivity and variability of a range of macrophyte endpoints were statistically tested with data from chronic, non-axenic, macrophyte toxicity tests. Five submersed freshwater macrophytes, four pesticides\\/biocides and 13 endpoints were included in the statistical analyses. Root endpoints, reflecting root growth, were most sensitive in the toxicity tests, while endpoints relating to biomass, growth and shoot length were less

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

2008-01-01

267

Periphyton photosynthesis as an indicator of effluent toxicity: Relationship to effects on animal test species  

Microsoft Academic Search

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

M Lewis

1992-01-01

268

Toxicity of copper and zinc assessed with three different earthworm tests  

Microsoft Academic Search

At present, standardised earthworm acute toxicity and reproduction tests are used to assess the toxicity of heavy metal contaminated soils. These tests are, however, time-consuming, laborious and costly, and in addition, some sublethal responses may remain overlooked. Avoidance of metal contaminated soils by earthworms may be a useful parameter when assessing ecological risks with a low test effort. The objective

Tuomas Lukkari; Marjo Aatsinki; Ari Väisänen; Jari Haimi

2005-01-01

269

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...

270

Anaerobic Dormancy Quantified in Artemia Embryos: A Calorimetric Test of the Control Mechanism  

Microsoft Academic Search

Continuous measurement of heat dissipation from brine shrimp embryos during reversible transitions from aerobic development to anaerobic dormancy demonstrates a primary role for intracellular pH (pHi) in this metabolic switching. Artificially elevating the depressed pHi during anoxia by adding ammonia markedly reactivates metabolism, as judged by increases in heat dissipation, trehalose catabolism, and the ratio of adenosine triphosphate to adenosine

Steven C. Hand; Erich Gnaiger

1988-01-01

271

A simple water toxicity test using Photobcicterium leiognathi  

Microsoft Academic Search

An alternative assay for the rapid, sensitive, and cost-effective evaluation of the toxicity of selected chemicals has been developed, using 6.0 mm filter paper discs of immobilised cultures of the luminous marine bacterium, Photobacterium leiognathi. This method, which can visually detect minute amounts of toxic chemicals in water, can be performed as a class experiment or an individual student investigation

Edward A. Quinto

2001-01-01

272

A new approach to practical acute toxicity testing  

Microsoft Academic Search

A method for the investigation of the acute toxicity of an unknown chemical substance, with an estimation on the LD50, is described. Using this, it is possible to obtain with 13 experimental animals adequate information on the acute toxicity and on the LD50. This method has no limitations and applies to drugs, agricultural and industrial chemicals. It can be used

Dietrich Lorke

1983-01-01

273

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

Microsoft Academic Search

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

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

2007-01-01

274

Rapid toxicity testing based on mitochondrial respiratory activity  

SciTech Connect

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

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

1990-05-01

275

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

USGS Publications Warehouse

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 interpretation of ambient test results depends 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 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 conditions change. Therefore, each test method has particular uses and limitations, and no single test has universal applicability. One of the most informative approaches to toxicity testing is to combine biochemical tests with other test methods in a 'battery of tests' that is diversified enough to characterize different types of toxicants and different trophic levels. However, such an approach can be costly, and if not carefully designed, it may not yield enough additional information to warrant the additional cost. The application of toxicity tests to large-scale water-quality assessments is hampered by a number of difficulties. Toxicity tests often are not sensitive enough to enable detection of most contaminant problems in the natural environment. Furthermore, because sensitivities among different species and test conditions can be highly variable, conclusions about the toxicant problems of an ecosystem are strongly dependent on the test procedure used. In addition, the experimental systems used in toxicity tests cannot replicate the complexity or variability of natural conditions, and positive test results cannot identify the source or nature of

Elder, John F.

1990-01-01

276

Identification of Rodent Carcinogens and Noncarcinogens Using Genetic Toxicity Tests: Premises, Promises, and Performance  

Microsoft Academic Search

The basic premises that guide genetic toxicity testing for identifying carcinogens and to support administrative and regulatory decisions are: the Salmonella mutagenicity test is a necessary component of testing schemes; a chromosome aberration test is needed in addition to a gene mutation test; a mammalian cell mutagenicity test is needed in addition to the Salmonella test;in vivotests are needed to

Errol Zeiger

1998-01-01

277

Assessment of whole effluent toxicity test variability: Partitioning sources of variability  

SciTech Connect

In this article, the authors quantify the variability of toxicity tests used in whole effluent toxicity (WET) testing and ambient water testing and demonstrate how knowledge of this variability can be used in the interpretation of compliance with WET limits in National Pollutant Discharge Elimination System permits. Whole effluent toxicity test endpoint accuracy and precision are important factors in establishing the credibility of test results. Initially, they developed a national data set consisting of raw reference toxicant data from freshwater and marine tests. The data set consisted of the most commonly used test species, protocols, and laboratories and included results from multiple tests over time within single laboratories. Using a random-effects model the authors evaluate and estimate the following variance components: between-laboratory variability, variability as a function of dilution concentration, variability of toxicity tests conducted over time, and random error. A variance components model was used to calculate the relative contribution of each variance component to the total variability in specific test endpoints. All analyses were conducted separately for specific reference toxicant, test species, and test protocol combinations. The authors demonstrate how to use the resulting variance estimates to calculate the minimum significant difference expected for specific test species and test protocols and present an application with WET test data. They present an application using actual WET test results and make recommendations for ensuring the quality of the information resulting from future WET testing.

Warren-Hicks, W.J.; Parkhurst, B.R.; Moore, D.R.J.; Teed, R.S.; Baird, R.B.; Berger, R.; Denton, D.L.; Pletl, J.J.

2000-01-01

278

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

National Technical Information Service (NTIS)

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

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

2004-01-01

279

The effects of Dechlorane Plus on toxicity and mRNA expression in chicken embryos: a comparison of in vitro and in ovo approaches.  

PubMed

Dechlorane Plus (DP) is an additive chlorinated flame retardant comprising two major isomers, syn- and anti-DP, that is used in a variety of commercial/industrial products. It has been detected in biotic and abiotic matrices including the eggs of herring gulls collected from the Laurentian Great Lakes. However, data on potential toxicological and molecular responses to exposure are lacking, especially for avian species. A combined in vitro/in ovo approach was used to determine concentration-dependent effects of DP in chicken embryonic hepatocytes (CEH) and chicken embryos following injection of DP into the air cell of eggs prior to incubation. Overt toxicity (i.e. cytotoxicity and pipping success) and mRNA expression levels of transcripts previously determined to be responsive to a brominated flame retardant were assessed in CEH and hepatic tissue. DP was not cytotoxic up to a maximum concentration of 3 ?M in CEH, and no effects on pipping success were observed up to the highest nominal dose group of 500 ng/g egg. A significant shift in isomeric content of syn- and anti-DP was detected between stock solutions of the commercial mixture and hepatic tissue; the proportion of the syn-DP isomer increased from 0.34 to 0.65 with a concomitant decrease of anti-DP from 0.66 to 0.35. None of the mRNA transcripts changed as a result of in vitro or in ovo exposure to DP indicating that, although there was concordance between the two approaches, DP may evoke its toxicity through other modes of action. At current environmental exposure levels, no adverse effects of DP on embryonic viability or pathways associated with the genes assessed are predicted. PMID:21539933

Crump, Doug; Chiu, Suzanne; Gauthier, Lewis T; Hickey, Nathan J; Letcher, Robert J; Kennedy, Sean W

2011-04-22

280

SEDIMENT TESTING INTERMITTENT RENEWAL SYSTEM FOR THE AUTOMATED RENEWAL OF OVERLYING WATER IN TOXICITY TESTS WITH CONTAMINATED SEDIMENTS  

EPA Science Inventory

A sediment testing intermittent renewal (STIR) system (stationary or portable) for invertebrate toxicity with contaminated sediments has been successfully developed and thoroughly tested at ERL-Duluth. oth the stationary and portable systems enable the maintenance of acceptable w...

281

Effect of the test media and toxicity of LAS on the growth of Isochrysis galbana  

Microsoft Academic Search

In this paper, the toxicity of linear alkylbenzene sulfonate (LAS) was evaluated in the marine microalga Isochrysis galbana using data of growth inhibition toxicity tests at 96-h exposure time. Toxicity was examined in standard conditions and by\\u000a means of the modification of two variables of the test media: (1) the dilution water and (2) the content of nutrients in the

M. C. Garrido-Perez; J. A. Perales-VargasMachuca; E. Nebot-Sanz; D. Sales-Márquez

2008-01-01

282

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

SciTech Connect

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

Simbeck, D.J.

1997-06-01

283

Proceedings of the Workshop on Subchronic Toxicity Testing.  

National Technical Information Service (NTIS)

Subchronic toxicity procedures are designed to determine the adverse effects that may occur with repeated exposure over a part of the average life span of an experiment animal. The workshop objectives included critically examining the subchronic study as ...

N. Page D. Sawhney M. G. Ryon

1980-01-01

284

Pyrrolizidine Alkaloids: Testing for Toxic Constituents of Comfrey.  

ERIC Educational Resources Information Center

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

Vollmer, John J.; And Others

1987-01-01

285

Application of the 10-d Acute and 28-d Chronic 'Leptocheirus plumulosus' Sediment Toxicity Tests to the Ambient Toxicity Assessment Program.  

National Technical Information Service (NTIS)

The goal of this report is to compare the U.S. EPA approved Leptocheirus plumulosus 10-d acute and 28-d chronic sediment test methods with sediment toxicity test methods used in the Ambient Toxicity Assessment program. The toxicity of estuarine and freshw...

D. J. Fisher L. T. Yonkos G. P. Ziegler B. S. Turley

2001-01-01

286

Sediment organic matter content as a confounding factor in toxicity tests with Chironomus tentans  

Microsoft Academic Search

Physicochemical characteristics of sediment unrelated to contaminant levels and bioavailability may influence the outcome of toxicity tests. In particular, sediment organic matter content has the potential to be a confounding factor in toxicity tests using the midge larva Chironomus tentans because the larvae are infaunal and feed on organic matter in the sediments. To examine the possibility, the authors conducted

Rebekah Lacey; Mary C. Watzin; Alan W. McIntosh

1999-01-01

287

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

Microsoft Academic Search

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

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

2007-01-01

288

Development of in Vitro Methods for Toxicity Testing of Workplace Air Contaminants  

Microsoft Academic Search

While the OECD test guidelines and mostly animal assays have been used to study the toxic effects of chemicals for many years, very little is known about the potential toxicity of vast majority of inhaled chemicals. Considering large number of chemicals and complex mixtures present in indoor and outdoor air, heavy reliance on animal test methods appear to be not

SHAHNAZ BAKAND; AMANDA HAYES; CHRIS WINDER

2009-01-01

289

Gammarus aequicauda (Crustacea: Amphipoda): A potential test species in marine sediment toxicity assessment  

Microsoft Academic Search

In this study, the amphipod Gammarus aequicauda was evaluated as a test organism for use in sediment toxicity bioassays. Sensitivity to noncontaminant variables, to the reference toxicants and to some contaminated field sediments was analysed. Amphipods were tolerant to various salinity and temperature combinations during a ten-day assay. The organisms tested with different type of diet showed highest survival on

Ermelinda Prato; Francesca Biandolino

2005-01-01

290

SUITABILITY OF SHEEPSHEAD MINNOWS ('CYPRINODON VARIEGATUS') FOR LIFE-CYCLE TOXICITY TESTS  

EPA Science Inventory

Entire life-cycle toxicity tests are practical with sheepshead minnows, Cyprinodon variegatus. This is the only estuarine fish that has been utilized successfully in life-cycle toxicity tests, using methods formulated only since 1973. Salinity, temperature, and spawning requireme...

291

Terrestrial isopods -- a good choice for toxicity testing of pollutants in the terrestrial environment  

SciTech Connect

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.

Drobne, D. [Univ. of Ljubljana (Slovenia). Dept. of Biology

1997-06-01

292

Evaluation of the aquatic toxicity of two veterinary sulfonamides using five test organisms  

Microsoft Academic Search

The aquatic toxicity of sulfaquinoxaline (SQO) and sulfaguanidine (SGD) was evaluated on the following test organisms: Daphnia magna (reproduction test), Pseudokirchneriella subcapitata, Scenedesmus dimorphus, Synecococcus leopoliensis (algal growth inhibition test) and Lemna gibba (duckweed growth inhibition test). Furthermore, the additivity of the two compounds was measured on D. magna (acute immobilisation test) and P. subcapitata (algal growth inhibition test) using

Marco De Liguoro; Vincenzo Di Leva; Guglielmo Gallina; Elisabetta Faccio; Gabriele Pinto; Antonino Pollio

2010-01-01

293

INTRALABORATORY COMPARISON OF THE EARLY LIFE-STAGE TOXICITY TEST USING THE SHEEPSHEAD MINNOW (CYPRINODON VARIEGATUS)  

EPA Science Inventory

The interlaboratory precision of the ASTM early life-stage toxicity test with the sheepshead minnow Cyprinodon variegatus) as investigated at five contract and two EPA laboratories using endosulfan nd pentachlorobenzene. ach laboratory conducted two tests with each hemical. ests ...

294

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...

295

Periphyton Photosynthesis as an Indicator of Effluent Toxicity: Relationship to Effects on Animal Test Species.  

National Technical Information Service (NTIS)

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 consequent...

M. A. Lewis

1992-01-01

296

Redbook 2000: IV.C.1 Short-Term Tests for Genetic Toxicity  

Center for Food Safety and Applied Nutrition (CFSAN)

... test for gene mutations in bacteria and an ... the general recommendations for genetic toxicity testing ... The FDA has modified these previous guidelines ... More results from www.fda.gov/food/guidanceregulation/guidancedocumentsregulatoryinformation

297

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 ...

298

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...

299

Effect of the test media and toxicity of LAS on the growth of Isochrysis galbana.  

PubMed

In this paper, the toxicity of linear alkylbenzene sulfonate (LAS) was evaluated in the marine microalga Isochrysis galbana using data of growth inhibition toxicity tests at 96-h exposure time. Toxicity was examined in standard conditions and by means of the modification of two variables of the test media: (1) the dilution water and (2) the content of nutrients in the test medium. For this purpose, a total of 10 toxicity test were designed: five dilution waters, four natural marine waters and one synthetic seawater; each in two different nutritive conditions, saturated nutrient concentration (SC) by the addition of modified f/2 nutritive medium, and natural nutrient concentration (NC), i.e., without the addition of f/2. At threshold toxicity levels, the dilution waters used in the test and the nutrient concentrations did not affect the toxicity of LAS. At IC50 concentrations, the toxicity of LAS is influenced by both variables: under SC conditions, the toxic effect of LAS diminishes, obtaining in all the tests IC50 > 10 mg/L LAS. Under NC conditions, IC50 concentrations ranging between 3.15 and 9.26 mg/L LAS have been obtained. PMID:18473164

Garrido-Perez, M C; Perales-VargasMachuca, J A; Nebot-Sanz, E; Sales-Márquez, D

2008-05-13

300

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

SciTech Connect

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

Pickett, J.B.

1992-07-06

301

Sediment toxicity tests involving immobilized microalgae (Phaeodactylum tricornutum Bohlin).  

PubMed

Populations of calcium-alginate immobilized marine diatom Phaeodactylum tricornutum were exposed to two sediments containing different levels of surfactant (LAS). Toxic responses were compared for free and immobilized algae. Although there is a direct relation between LAS content in sediment and inhibition, immobilized algae suffered less inhibition than free cells, over all when fluorescence is chosen as a biomarker for biomass. When cells are counted from dissolved beads, inhibition of growth is closer to the values found for free cells. Immobilization can be useful for in situ experiments but protection of cells inside the alginate beads against toxic capacity of xenobiotics must be taken into account. PMID:17157382

Moreno-Garrido, I; Lubián, L M; Blasco, J

2006-12-06

302

Pilot study for ambient toxicity testing in Chesapeake bay. Year two report  

SciTech Connect

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.

Hall, L.W.; Ziegenfuss, M.C.; Fischer, S.A.; Anderson, R.D.; Killen, W.D.

1992-11-01

303

Anaerobic dormancy quantified in artemia embryos: a calorimetric test of the control mechanism.  

PubMed

Continuous measurement of heat dissipation from brine shrimp embryos during reversible transitions from aerobic development to anaerobic dormancy demonstrates a primary role for intracellular pH(pH(i))in this metabolic switching. Artificially elevating the depressed pH(i) during anoxia by adding ammonia markedly reactivates metabolism, as judged by increases in heat dissipation, trehalose catabolism, and the ratio of adenosine triphosphate to adenosine diphosphate. Energy flow during anaerobic dormancy is suppressed to 2.4 percent of aerobic values, which is the lowest percentage thus far reported for euryoxic animals. Use of diguanosine tetraphosphate stores cannot account for this observed heat dissipation. Thus, mobilizing trace amounts of trehalose may explain the energy metabolism during quiescence. PMID:17769739

Hand, S C; Gnaiger, E

1988-03-18

304

Current status of conducting function tests in repeated dose toxicity studies in Japan.  

PubMed

It seems desirable to conduct as many function tests as possible in repeated dose toxicity studies, but is it practicable? The current status of conducting function tests in repeated dose toxicity studies in Japan was investigated by a literature survey of more than one thousand papers published in seven Japanese toxicology journals during the past 10 years and by a questionnaire survey directed to toxicologists among the Japan Pharmaceutical Manufacturers Association (JPMA) member companies. The function tests often carried out in repeated dose toxicity studies were, for example: 1) electro-retinography (ERG) and visually evoked potential (VEP) for visual test and tonometer for intraocular pressure; 2) auricular reflex, evoked response audiometry (ERA) and auditory brainstem response (ABR) to sound stimuli; 3) respiration and heart rate, electrocardiogram (ECG) and blood pressure by noninvasive cuff methods or using electronic devices such as telemetry; 4) body temperature, spontaneous motility and some adaptation tests (using rotarod and sloped plate in rats); 5) indocyanin (ICG) or bromosulfophtalein (BSP) for hepatic test; 6) phenolsulfonphtalein (PSP) and creatinine clearance for renal test; and 7) immunoglobulin, leukocyte phagocytosis, lymphocyte blastgenesis and natural killer cell (NK) for immuno-reaction test. Limitations to conducting function tests in repeated dose toxicity studies and issues to be resolved were discussed, based on questions and suggestions given by the respondents to the questionnaire. Although it certainly seemed desirable to conduct as many function tests as possible in repeated dose toxicity studies, most of the function tests so far introduced into toxicity studies were not satisfactory, because those tests could not be carried out under the restricted conditions of repeated dose toxicity studies, and not much reliable data from function tests were obtainable. A variety of function tests should firstly be incorporated into single dose toxicity studies together with development of a new concept for methodology in safety pharmacology. PMID:9442447

Matsuzawa, T; Hashimoto, M; Nara, H; Yoshida, M; Tamura, S; Igarashi, T

1997-12-01

305

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

PubMed Central

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

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

2011-01-01

306

Testing retinal toxicity of drugs in animal models using electrophysiological and morphological techniques  

Microsoft Academic Search

Drugs are frequently tested for retinal toxicity in animal models in order to address applied and basic research questions.\\u000a When a retinal toxicity study is designed, the researcher needs to consider several factors depending on his\\/her research\\u000a questions. Among the factors that need to be addressed before a toxicity study is conducted are: the animal species to be\\u000a used, choice

Ido Perlman

2009-01-01

307

Toxicity estimation of magnetic fluids in a biological test  

NASA Astrophysics Data System (ADS)

Uniform magnetic nanoparticles were prepared by chemical coprecipitation. Decanoic acid was used as the first surfactant to minimize the magnetic dipole dipole interaction, and starch, citric acid, decanoic acid, polyethylene glycol and alginic acid were selected as the second surfactants for hydrophilicity. The applied second surfactants strongly influenced the biological toxicity of the magnetic particles as well as the properties of magnetic fluids.

Park, S. I.; Lim, J. H.; Kim, J. H.; Yun, H. I.; Kim, C. O.

2006-09-01

308

Sediment toxicity tests involving immobilized microalgae ( Phaeodactylum tricornutum Bohlin)  

Microsoft Academic Search

Populations of calcium-alginate immobilized marine diatom Phaeodactylum tricornutum were exposed to two sediments containing different levels of surfactant (LAS). Toxic responses were compared for free and immobilized algae. Although there is a direct relation between LAS content in sediment and inhibition, immobilized algae suffered less inhibition than free cells, over all when fluorescence is chosen as a biomarker for biomass.

I. Moreno-Garrido; L. M. Lubián; J. Blasco

2007-01-01

309

Niacin Toxicity Resulting from Urine Drug Test Evasion  

Microsoft Academic Search

Background: Niacin, a well-established agent for treating dyslipidemia, has been promoted on the Internet as a method for passing urine drug screening, although there are no data to support its use for this purpose. In a handful of cases, this practice has resulted in serious niacin toxicity. Objectives: The aim of this article is to describe a unique clinical presentation

Anne M. Daul; Michael C. Beuhler

2011-01-01

310

Baker's yeast assay procedure for testing heavy metal toxicity  

Microsoft Academic Search

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

Gabriel Bitton; Ben Koopman; Hsien-Deng Wang

1984-01-01

311

Toxicity Testing of Antimalarial Drugs in Swine and Dogs.  

National Technical Information Service (NTIS)

Acute, subacute, and chronic toxicity studies and photosensitization studies were conducted in swine and dogs using antimalarial compounds singularly or in combination. The subcutaneous administration of WR-9838-B, 5 mg/kg or 10 mg/kg, for 15 consecutive ...

W. W. Bay C. A. Gleiser R. G. Feldman K. R. Pierce K. M. Charlton

1969-01-01

312

Triazole-induced gene expression changes in the zebrafish embryo.  

PubMed

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

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

2012-06-02

313

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

PubMed

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

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

2006-08-01

314

Development and evaluation of multispecies test protocols for assessing chemical toxicity  

SciTech Connect

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

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

1985-06-01

315

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

SciTech Connect

Short-term whole effluent toxicity testing, which is currently a requirement of the U.S. EPA`s National Pollution Discharge Elimination System (NPDES), commonly uses the cladoceran species Ceriodaphnia dubia. Despite the advantages to using a common test species to model the toxic effects of effluents, it could be argued that toxicity test results would be more meaningful if a wider variety of test organisms were commonly used. One particular argument against C. dubia is that tests conducted with this species do not always reflect local, site-specific conditions. The careful selection and use of an indigenous test species would produce a more realistic model of local instream effects and would account for regional differences in water quality. Permitted effluent discharges from Savannah River Site (SRS), a government weapons facility operated by the U.S. Department of Energy, require toxicity testing with C. dubia. However, water quality in these receiving streams is markedly different (lower pH and hardness) from standard laboratory water used for the culturing and testing of C. dubia, and it has been shown that this receiving water presents varying degrees of toxicity to C. dubia. Based on these results, it is possible that toxic effects observed during an effluent study could be the result of test organism stress from the dilution water and not the effects of SRS effluents. Therefore, this study addressed the substitution of C. dubia with an indigenous cladoceran species, Daphnia ambigua for routine regulatory testing at SRS. Given the indigenous nature of this species, combined with the fact that it has been successfully cultured by other investigators, D. ambigua was ideal for consideration as a replacement for C. dubia, but further study of the overall success and sensitivity of laboratory-reared D. ambigua was required. This investigation determined that D. ambigua could be laboratory cultured with only minimal changes to established regulatory protocol and that the life-cycle characteristics of this species were conducive to traditional acute and chronic aquatic toxicity test methods. Acute toxicity tests showed that when comparing LC50 values for C. dubia and D. ambigua, D. ambigua was less sensitive to some toxicants (sodium chloride, copper sulfate, and sodium lauryl sulfate) while more sensitive to others (chlorpyrifos). Results of chronic tests with copper sulfate and sodium chloride resulted in the same NOEC/LOEC values for both species. When exposed to unaltered SRS stream water, C. dubia demonstrated a `toxic` response for two of the three streams tested, while reproduction for D. ambigua was higher in all stream samples. Acute toxicity tests with sodium chloride in stream water, generally followed the sensitivity trend noted in tests conducted with regular laboratory water.

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

1997-09-01

316

Commentary on ‘‘Toxicity Testing in the 21st Century: A vision and a Strategy’’  

Microsoft Academic Search

Toxicity Testing in the 21st Century: A Vision and a Strategy (NRC, 2007) presents a bold plan for chemical toxicity testing that replaces whole-animal tests with cell-culture, genetic, other in-vitro techniques, computational methods, and human monitoring. Although the proposed vision is eloquently described, and recent advances in in-vitro and in-silico methods are impressive, it is difficult believe that replacing in-vitro

Robert F Phalen

2010-01-01

317

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

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.

McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

2009-01-01

318

Development of protocols for chronic toxicity testing of Pacific marine species  

SciTech Connect

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.

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

1990-03-01

319

An Integrated in Vitro Approach for Toxicity Testing of Airborne Contaminants  

Microsoft Academic Search

While it is possible to establish the chemical composition of air pollutants through conventional air sampling and analytical techniques, such data do not provide direct measures of toxicity and the potential mechanisms that induce adverse effects. The aim of this study was to optimize in vitro methods for toxicity testing of airborne contaminants. An integrated approach was designed in which

Shahnaz Bakand; Amanda Hayes; Chris Winder

2007-01-01

320

Rapid toxicity screening tests for aquatic biota. 1. Methodology and experiments with Daphnia magna  

Microsoft Academic Search

A promising new and rapid toxicity screening test was developed, the concept and principles of which are presented. The method consists of visual observation of in vivo inhibition of an enzymatic process, using a fluorescent substrate. Juvenile Daphnia magna was exposed to a toxicant dilution series for 1 h, after which the substrate was added and the enzymatic inhibition was

C. R. Janssen; G. Persoone

1993-01-01

321

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...

322

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...

323

INTERLABORATORY ROOT ELONGATION TESTING OF TOXIC SUBSTANCES ON SELECTED PLANT SPECIES  

EPA Science Inventory

Four contract laboratories and three EPA laboratories participated in the inter-laboratory testing of 10 toxic substances on a representative plant species from five families. Seeds were germinated on filter paper saturated in a solution of the toxic substance and incubated for 1...

324

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

Microsoft Academic Search

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

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

2009-01-01

325

Relative sensitivities of toxicity test protocols with the amphipods Eohaustorius estuarius and Ampelisca abdita  

Microsoft Academic Search

A series of dose–response experiments was conducted to compare the relative sensitivities of toxicity test protocols using the amphipods Ampelisca abdita and Eohaustorius estuarius. A. abdita is one of the dominant infaunal species in the San Francisco Estuary, and E. estuarius is the primary sediment toxicity species used in the San Francisco Estuary Regional Monitoring Program. Experiments were conducted with

Brian S. Anderson; Sarah Lowe; Bryn M. Phillips; John W. Hunt; Jennifer Vorhees; Sara Clark; Ronald S. Tjeerdema

2008-01-01

326

Periphyton photosynthesis as an indicator of effluent toxicity: Relationship to effects on animal test species  

SciTech Connect

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.

Lewis, M.A.

1992-01-01

327

Bioavailability of fluoranthene in freshwater sediment toxicity tests  

Microsoft Academic Search

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

Burton C. Suedel; John H. Rodgers; Philip A. Clifford

1993-01-01

328

Lethal effect of dehydroleucodine (DhL) on amphibian Bufo arenarum embryos.  

PubMed

The dehydroleucodine is a sesquiterpene lactone isolated from Artemisia douglasiana Besser which is used in popular medicine. Toxicity tests using embryos of amphibian have been widely used in order to predict toxic effects of different compounds. However, to our knowledge, there are not studies focussed on the toxic effects of dehydroleucodine on Bufo arenarum, which is an anuran widely distributed in South America. The effect of dehydroleucodine on the survival of embryos was evaluated in an acute test during the early life stage of B. arenarum embryos. Lethality and the degree of adverse effects were dehydroleucodine dose-dependent. Overall, amphibian early life stages appeared to be more susceptible to the embryotoxicity associated with exposure to dehydroleucodine, especially at concentration greater that 3mM. This increased susceptibility may result from the relatively high rate of cellular differentiation and morphogenesis that occurs at this early stage of development. PMID:22240414

Moreno, Liliana Elizabeth; Juárez, Américo Osvaldo; Pelzer, Lilian Eugenia

2012-01-03

329

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....

330

A simple, cost-effective multispecies toxicity test using organisms with a cosmopolitan distribution  

Microsoft Academic Search

Difficulties in making accurate, ecosystem-level predictions of environmental effects of chemicals, mixtures, and effluents based solely on the results of tests on single species have necessitated the development of more environmentally realistic, predictive testing methods. This paper describes a multispecies, community-level toxicity test based on the colonization of artificial substrates by microbial species. Tests examined the colonization of initially barren

John Cairns; James R. Pratt; B. R. Niederlehner; P. V. McCormick

1986-01-01

331

Development of cytotoxicity tests for assessment of the toxicity of water samples taken from the environment  

Microsoft Academic Search

Different methods of measuring cytotoxicity have been investigated in order to establish a test system for assessment of the toxicity of water samples. Ideally this should be highly sensitive and rapid to perform. Four variations of the neutral red uptake test have been compared with the MTT test and ATP determination. Chinese hamster V79\\/4 cells were used as the test

D. J. Benford; S. Good

2009-01-01

332

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

Microsoft Academic Search

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

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

2011-01-01

333

Whole sediment toxicity tests for metal risk assessments: on the importance of equilibration and test design to increase ecological relevance.  

PubMed

Current laboratory-based approaches for predicting metal toxicity in sediments exhibit a number of limitations. The most important are (1) a lack of sufficient equilibration resulting in unrealistically low pH values or unnaturally high porewater metal concentrations and (2) an inadequate test design regarding the metal concentrations selected for spiking. The present study illustrates that by explicitly accounting for these limitations, one obtains reliable and environmentally realistic toxicity data, thus advancing the metal risk assessments of sediments. To this end, a toxicity test design with natural sediments was developed in which the administered metal concentrations were selected to comprise a range of the difference between the molar concentration of simultaneously extracted metals and acid volatile sulfides (SEM-AVS) closely surrounding zero. In addition, the test design presented includes a 35- or 40-d equilibration period with overlying water renewal during which conductivity, pH, and metal concentrations in the overlying water are monitored. This allows toxicity testing to start after equilibrium for these parameters has been reached. This test design was applied to Ephoron virgo (Olivier, 1791), Gammarus pulex (Linnaeus, 1758), and Lumbriculus variegatus (Mueller, 1774) exposed to Zn and Pb. These tests indicated that the general concept of absence of toxicity when SEM-AVS<0 could not be rejected. However, the onset of Zn toxicity occurred at lower concentrations than generally assumed. PMID:23401179

Vandegehuchte, Michiel B; Nguyen, Lien T H; De Laender, Frederik; Muyssen, Brita T A; Janssen, Colin R

2013-04-01

334

Comparison of Daphnia magna , rainbow trout and bacterial-based toxicity tests of Ontario Hydro aquatic effluents  

Microsoft Academic Search

Over a one year program of intensive monitoring of effluents from Ontario Hydro's nuclear, fossil and hydroelectric generating facilities, theDaphnia magna and rainbow trout,Oncorhynchus mykiss, acute toxicity tests correlated well, with 61 % of the toxic effluents toxic to both species. If the effluent was toxic to only one of the test species it was generally toxic toD. magna, with

D. W. Rodgers; J. Schröder; L. Vereecken Sheehan

1996-01-01

335

Toxicity testing strategies for assessing water-quality conditions in receiving streams  

SciTech Connect

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.

Stewart, A.J.

1994-12-31

336

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

SciTech Connect

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

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

1996-12-01

337

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

SciTech Connect

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}.

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

1998-01-01

338

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...

339

Evaluation of Toxicity Test Procedure for Screening Treatability Potential of Waste in Soil.  

National Technical Information Service (NTIS)

A toxicity procedure has been developed and proposed for use in establishing acceptable initial loading rates and detoxification potentials for hazardous industrial waste when combined with soil. Screening test results are used to establish a range of loa...

J. E. Matthews L. Hastings

1987-01-01

340

MOTOR ACTIVITY: A SURVEY OF METHODS WITH POTENTIAL USE IN TOXICITY TESTING  

EPA Science Inventory

Activity measurements are expected to have widespread use in toxicity testing. The multifaceted nature of motor activity will directly influence the selection of a measurement technique since the relative contribution of various motor acts to any particular measurement will depen...

341

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

PubMed

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

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

2013-03-16

342

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

EPA Science Inventory

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

343

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....

344

EPA's Toxcast â?˘ 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 ...

345

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 ...

346

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 ...

347

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...

348

Toxic stress prioritizes and imbalances stem cell differentiation: implications for new biomarkers and in vitro toxicology tests.  

PubMed

This hypothesis and review introduces rules of stem cell stress responses that provide biomarkers and alternative testing that replaces or reduces gestational tests using whole animals. These rules for the stress responses of cultured stem cells validate the organismal strategy of the stress response and show that it emulates what must happen if the conceptus implants during a response to stress in vivo. Specifically there is a profound threshold during a stress dose response where stem cell accumulation is significantly reduced. Below this threshold stress enzymes manage the stress response by converting anabolic to catabolic processes and by suppressing apoptosis, without affecting differentiation. However above this threshold the stem cell survival response converts to an organismal survival response where stress enzymes switch to new substrates and mediate loss of potency factors, gain of early essential differentiated lineages, and suppression of later essential lineages. Stressed stem cells 'compensate' for lower accumulation rates by differentiating a higher fraction of cells, and the organismal survival response further enhances adaptation by prioritizing the differentiation of early essential lineages. Thus compensatory and prioritized differentiation and the sets of markers produced are part of a response of cultured embryos and stem cells that emulate what must happen during implantation of a stressed gestation. Knowledge of these markers and use of stressed stem cell assays in culture should replace or reduce the number of animals needed for developmental toxicity and should produce biomarkers for stressed development in vitro and in vivo. PMID:22239079

Rappolee, Daniel A; Xie, Yufen; Slater, Jill A; Zhou, Sichang; Puscheck, Elizabeth E

2012-02-01

349

Toxic stress prioritizes and imbalances stem cell differentiation: implications for new biomarkers and in vitro toxicology tests  

PubMed Central

This hypothesis and review provides rules of stem cell stress responses that provide biomarkers and alternative testing that replaces or reduces gestational tests using whole animals. These rules for the stress responses of cultured stem cells validate the organismal strategy of the stress response and show that it emulates what must happen if the conceptus implants during a response to stress in vivo. Specifically there is a profound threshold during a stress dose response where stem cells accumulate significantly less well. Below this threshold stress enzymes manage the stress response by converting catabolic to anabolic processes and by suppressing apoptosis, without affecting differentiation. However above this threshold the stem cell survival response converts to an organismal survival response where stress enzymes switch to new substrates and mediate loss of potency factors, gain of early essential differentiated lineages, and suppression of later essential lineages. Stressed stem cells ‘compensate’ for lower accumulation rates by differentiating a higher fraction of cells, and the organismal survival response further enhances adaptation by prioritizing the differentiation of early essential lineages. Thus compensatory and prioritized differentiation and the sets of markers produced are part of a response of cultured embryos and stem cells that emulate what must happen during implantation of a stressed gestation. Knowledge of these markers and use of stressed stem cell assays in culture should replace or reduce the number of animals needed for developmental toxicity and should produce biomarkers for stressed development in vitro and in vivo.

Rappolee, Daniel A.; Xie, Y.; Slater, J.A.; Zhou, S.; Puscheck, E.E.

2012-01-01

350

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

USGS Publications Warehouse

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 conditions change. One of the most informative approaches for toxicity testing is to combine biochemical tests with other test methods in a ' battery or tests ' that is diversified enough to characterize different types of toxicants and different trophic levels. (Lantz-PTT)

Elder, J. F.

1989-01-01

351

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

SciTech Connect

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.

Frenier, W.W. [HydroChem Industrial Services Inc., Houston, TX (United States)

1997-02-01

352

Comparison of the toxicity of the combustion products from a flexible polyurethane foam and a polyester fabric evaluated separately and together by the NBS (National Bureau of Standards) toxicity test method and a cone radiant heater toxicity test apparatus  

NASA Astrophysics Data System (ADS)

Representative specimens of flexible polyurethane foam and polyester fabric were thermally decomposed separately and together in order to compare the toxicity of the combustion products from the combined materials with those from the single homogeneous materials and to compare the toxicological results obtained with the NBS Toxicity Test Method with those using a cone radiant heater toxicity test apparatus. Gas concentrations (CO, CO2, O2 and HCN), blood carboxyhemoglobin, and LC(sub 50) values in Fischer 344 rats were determined for the materials under both flaming and non-flaming conditions. With the NBS Toxicity Test Method, the results of the non-flaming combined experiments indicated that both materials contributed in an additive manner to the concentration of the combustion products. However, under flaming conditions, the generation of HCN is greater than that predicted from the addition of the maximum amounts produced by the materials separately.

Levin, B. C.; Braun, E.; Gurman, J. L.; Paabo, M.

1986-11-01

353

Acute toxicity tests on raw leachate from a Malaysian dumping site.  

PubMed

Leachate samples collected from the Ampar Tenang open dumping site at Dengkil, Malaysia, were analyzed for acute toxicity. Two in vivo toxicity tests, Acute Oral Toxicity (AOT) and Primary Skin Irritation (PSI), were performed using Sprague Dawley rats and New Zealand Albino rabbits, respectively. The leachate samples were also analyzed chemically for nitrate and phosphate, ammonia-nitrogen, Kjeldahl-nitrogen and Chemical Oxygen Demand (COD). Results from both the AOT and PSI tests showed that the leachate did not contribute to acute toxicity. The AOT test yielded a negative result: no effect was observed in at least half of the rat population. The PSI test on rabbits produced effects only at a leachate concentration of 100%. However, the skin irritation was minor, and the test returned a negative result. The four chemical tests showed high levels of nutrient pollution in the leachate. The nitrate and phosphate concentrations were 2.1 mg/L and 23.6 mg/L, respectively. Further, the ammonia-nitrogen concentration was 1,000 mg NH(3)-N/L the Kjeldahl-nitrogen level was 446 mg NH(3)-N/L, and the Chemical Oxygen Demand was 1,300 mg/L. The in vivo toxicity and chemical analyses showed that the leachate is polluted but not acutely toxic to organisms. PMID:20107265

Sujá, Fatihah; Yusof, Arij; Osman, Md Anuar

2010-01-01

354

Alternative approaches can greatly reduce the number of fish used for acute toxicity testing.  

PubMed

Acute toxicity tests with algae, daphnids, and fish are required for the classification and environmental risk assessment of chemicals. The degree of risk is determined by the lowest of these acute toxicity values. Many ecotoxicological programs are seeking to reduce the numbers of fish used in acute toxicity testing. The acute threshold test is a recently proposed strategy that uses, on average, only 10 (instead of 54) fish per chemical. We examined the consequences of reducing the number of fish used in toxicity testing on the ultimate outcome of risk assessments. We evaluated toxicity data sets for 507 compounds, including agrochemicals, industrial chemicals, and pharmaceuticals from our internal database. Theoretical applications of the acute threshold test gave similar results to those obtained with the standard fish median lethal concentration (LC50) test but required only 12% as many fish (3195 instead of 27,324 fish used for all compounds in the database). In 188 (90%) of the 208 cases for which a complete data set was available, the median effect concentration for algae or daphnids was lower than the LC50 for fish. These results show that replacement of the standard fish LC50 test by the acute threshold test would greatly reduce the number of fish needed for acute ecotoxicity testing without any loss of reliability. PMID:16704064

Hoekzema, Conny C; Murk, Albertinka J; Van de Waart, Beppy J; Van der Hoeven, Jan C M; De Roode, Daphne F

2006-05-01

355

DEVELOPMENT OF A FATE/TOXICITY SCREENING TEST  

EPA Science Inventory

A shake-flask screening test was designed to rapidly evaluate the relative degradation rates of a wide spectrum of chemicals, each compared to methyl parathion. Test chemicals evaluated were bolero, bravo, dibutylphthalate, dimilin, dursban, endosulfan, hoelon, pentachlorobenzene...

356

Seven-Day Life-Cycle Cladoceran Toxicity Test.  

National Technical Information Service (NTIS)

A three-brood life cycle test for Ceriodaphnia reticulata, using renewal techniques, that can be completed in 7 d is described. The test is convenient when samples to be tested are limited in volume or when time is especially important, such as in on-site...

D. I. Mount T. J. Norberg

1984-01-01

357

Toxicity tests of effluents with marsh plants in water and sediment  

SciTech Connect

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).

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

1991-01-01

358

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...

359

Use of the Amphipod Crustacean 'Hyalella Azteca' in Freshwater and Estuarine Sediment Toxicity Tests.  

National Technical Information Service (NTIS)

Hyalella azteca (Saussure), which are currently used in toxicity tests with freshwater sediments, were tested to determine their suitability for tests with estuarine sediments. Reproduction was good after 24 d at and below 12.5 g/l (ppt) salinity in water...

A. V. Nebeker C. E. Miller

1988-01-01

360

Development of an alternative artificial soil for earthworm toxicity testing in tropical countries  

Microsoft Academic Search

The standard soil invertebrate toxicity tests developed by OECD and ISO use an artificial soil as the test substrate, which contains sphagnum peat as a component. This type of peat is not widely available. Investigation of possible alternative substrates using locally available materials therefore is vital for performing such ecotoxicity tests, particularly in the tropics. We studied the suitability of

Cornelis A. M. van Gestel

2009-01-01

361

INTERLABORATORY COMPARISON OF A 28-DAY TOXICITY TEST WITH THE POLYCHAETE 'NEANTHES ARENACEODENTATA'  

EPA Science Inventory

An interlaboratory comparison of toxicity tests with the polychaete Neanthes arenaceodentata was conducted to determine the amount of variability expected with this test. Six laboratories each conducted two 28-day flow-through tests, one with silver nitrate (AgNO3) as the toxican...

362

Microtox and Spirillum volutans tests for assessing toxicity of environmental samples  

SciTech Connect

Two short-term bacterial toxicity tests that have received a great deal of attention during the last few years are the Microtox and Spirillum volutans assays. The former involves monitoring changes in the light output from luminescent bacteria (Photobacterium phosphoreum) in a temperature controlled photometer when exposed to various concentrations of toxic substances. In the S. volutans assay, motility patterns of this large aquatic bacterium are used as the test endpoints. As part of the authors' program in assembling and establishing a battery of short-term bacterial toxicity tests, they examined the use of Microtox and S. volutans for determining the toxicity of a wide variety of environmental samples. Samples examined included potable and surface waters, industrial effluents, soil/sludge extracts and landfill leachates. Some of the results are presented in this paper.

Coleman, R.N.; Qureshi, A.A.

1985-10-01

363

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

SciTech Connect

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 limited to sediment depths of 10 cm or greater, which is outside of the primary zone of biological activity. Further, exposure to site sediments did not have any effects on test organisms, and macroinvertebrate communities did not indicate impairment at the oil production site as compared to a reference site. In situ experiments with H. azteca and C. fluminea, indicated a sublethal site effect (on growth of both species), but these could not be definitively linked with produced water infiltration. Severe weather conditions (drought followed by flooding) negatively influenced the intensity of lake sampling aimed at delineating produced water infiltration. Due to the lack of clear evidence of produced water infiltration into the sub-littoral zone of the lake, it was not possible to assess whether the laboratory bioassays of produced water effectively indicate risk in the receiving system. However, the acutely toxic nature of the produced water and general lack of biological effects in the lake at the oil production site suggest minimal to no produced water infiltration into surficial lake sediments and the near-shore water column. This study was able to demonstrate the utility of ion toxicity modeling to support data from toxicity identification evaluations aimed at identifying key toxic constituents in produced water. This information could be used to prioritize options for treating produced water in order to reduce toxic constituents and enhance options for reuse. The study also demonstrated how geographic information systems, toxicity modeling, and toxicity assessment could be used to facilitate future site assessments.

Joseph Bidwell; Jonathan Fisher; Naomi Cooper

2008-03-31

364

Sediment toxicity evaluation for hexachlorobenzene: spiked sediment tests with Leptocheirus plumulosus, Hyalella azteca, and Chironomus tentans.  

PubMed

Hexachlorobenzene (HCB) is a hydrophobic organic chemical that has shown a lack of toxicity in aquatic tests at concentrations up to and exceeding the solubility limit. The equilibrium partitioning approach to deriving sediment quality benchmarks, which assumes that toxicity can be predicted based on contaminant concentrations in interstitial water, predicts that HCB will not produce direct toxicity to benthic invertebrates as a sediment contaminant. However, the potential for toxicity due to direct exposure to sediment-adsorbed HCB has not been thoroughly established. This study evaluated the survival and growth of the estuarine amphipod Leptocheirus plumulosus, the freshwater amphipod Hyalella azteca, and the midge Chironomus tentans (freshwater) following 10-day exposure to sediment spiked with a range of HCB concentrations. H. azteca was tested under both freshwater and estuarine (10 ppt salinity) conditions. No significant toxicity was observed for any test species at the highest test concentration (60 mg/kg normalized to 1% organic carbon). Minimum detectable differences were less than or equal to 20% for three of eight test endpoints. The observed results add to the available weight of evidence indicating a limited potential for HCB-related sediment toxicity to benthic invertebrates. PMID:9776774

Fuchsman, P C; Barber, T R; Sheehan, P J

1998-11-01

365

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

Microsoft Academic Search

A number of procedures have been developed to assess toxic effects on the early life stages of salmonid fish. In this study\\u000a 13 rainbow trout embryo development relatively short-term (7 to 90 day) procedures were reviewed. Three 7-day methods from\\u000a the published literature and three modifications developed at AQUA-Science (A-S) were evaluated in the laboratory. Based on\\u000a that evaluation, A-S methods

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

2009-01-01

366

40 CFR 797.1400 - Fish acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...sufficient to maintain the dissolved oxygen concentration above the recommended levels and the ammonia concentration...µg/l. (ii) Dissolved oxygen concentration. ...minnows. (iii) Temperature. The test...

2009-07-01

367

40 CFR 797.1400 - Fish acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...sufficient to maintain the dissolved oxygen concentration above the recommended levels and the ammonia concentration...µg/l. (ii) Dissolved oxygen concentration. ...minnows. (iii) Temperature. The test...

2010-07-01

368

FETAX assay for evaluation of developmental toxicity.  

PubMed

The Frog Embryo Teratogenesis Assay Xenopus (FETAX) test is a development toxicity screening test. Due to the small amount of compound needed and the capability to study organogenesis in a short period of time (96 h), FETAX test constitutes an efficient development toxicity alert test when performed early in drug safety development. The test is conducted on fertilized Xenopus laevis mid-blastula stage eggs over the organogenesis period. Compound teratogenic potential is determined after analysis of the mortality and malformation observations on larva. In parallel, FETAX test provides also information concerning embryotoxic effect based on larva length. PMID:20972758

Mouche, Isabelle; Malesic, Laure; Gillardeaux, Olivier

2011-01-01

369

Salinity Tolerance of Daphnia magna and Potential Use for Estuarine Sediment Toxicity Tests  

Microsoft Academic Search

.  \\u000a \\u000a Daphnia magna Straus, a common organism used for freshwater sediment toxicity tests, was evaluated to determine its tolerance to salinity\\u000a and suitability for tests with estuarine water and sediments. Daphnids were exposed for 2 to 21 days to salinity in a variety\\u000a of water-only tests, in tests with freshwater sediment overlain by salt water, and in tests with estuarine

G. S. Schuytema; A. V. Nebeker; T. W. Stutzman

1997-01-01

370

Sporadic mortality in chronic toxicity tests using Pimephales promelas (Rafinesque): Cases of characterization and control  

SciTech Connect

In whole effluent toxicity tests, organisms are exposed to various effluent concentrations for a specific time period to estimate the potential effects of an effluent on a receiving stream. Laboratories typically have good success performing valid chronic toxicity tests. However, some difficulty in conducting valid chronic whole effluent toxicity tests with Pimephales promelas (fathead minnow) has been encountered as a result of sporadic control mortality. Some investigators report an interference that causes anomalous patterns of survival in chronic fathead minnow tests. This interference has been termed sporadic mortality phenomenon. Characteristics of sporadic mortality phenomenon include high variability among replicates, nonmonotonic dose responses, mortality beginning on or about day 4 of the test, and fungal growths often observed on the larvae. Histopathologic examinations often indicate bacterial and/or fungal infections on fish exhibiting symptoms of sporadic mortality phenomenon. The most plausible explanation of sporadic mortality phenomenon is a naturally occurring pathogen or pathogens that interfere with the test method. This interference may invalidate tests or falsely indicate toxicity. Sporadic mortality phenomenon can be reduced or eliminated by sample treatments intended to inactivate (heating, antibiotics, or ultraviolet light) or remove (filtration) pathogenic microorganisms. These methods must be used with forethought because of their potential to alter the toxicity of a sample.

Downey, P.J.; Fleming, K.; Guinn, R.; Chapman, N.; Varner, P.; Cooney, J.D.

2000-01-01

371

No-observed-effect concentrations in batch and continuous algal toxicity tests  

SciTech Connect

In this study, the authors compare the no-observed-effect concentrations (NOECs) of Cd, Ni, Zn, Cu, and Pb based on different response parameters, using batch and continuous algal toxicity tests. For both batch and continuous tests, parameters based on total cell volume (TCV) were found to be less sensitive than those related to cell densities. The above observation mainly occurred because, under the stresses from metal toxicants evaluated in this and a previous study, the mean cell volume (MCV) of algae increased considerably. The increase of MCV compensates for the effects brought about by the reduction in cell density and eventually results in less variation in TCVs. This study shows that parameters based on cell density are quite sensitive and ideal for the estimation of NOECs. In addition, comparison of the NOEC values derived from different culture techniques shows that the continuous methods generally yields lower NOEC values than that obtained by the batch tests. The results of this study also indicate that the NOEC provides more protection to the test organism than the effective concentration at 10% growth reduction (EC10). For toxicity test methods that produce small variations among replicates, the NOEC is still a good indicator of low toxic effect. Furthermore, for the continuous algal toxicity test, a relatively simple approach is proposed to determine the NOEC values based on the algal culture's control charts. The proposed method produced identical results as those based on conventional hypothesis-testing methods.

Chao, M.R.; Chen, C.Y.

2000-06-01

372

Recreating the seawater mixture composition of HOCs in toxicity tests with Artemia franciscana by passive dosing.  

PubMed

The toxicity testing of hydrophobic organic compounds (HOCs) in aquatic media is generally challenging, and this is even more problematic for mixtures. The hydrophobic properties of these compounds make them difficult to dissolve, and subsequently to maintain constant exposure concentrations. Evaporative and sorptive losses are highly compound-specific, which can alter not only total concentrations, but also the proportions between the compounds in the mixture. Therefore, the general aim of this study was to explore the potential of passive dosing for testing the toxicity of a PAH mixture that recreates the mixture composition found in seawater from a coastal area of Spain, the Bay of Algeciras. First, solvent spiking and passive dosing were compared for their suitability to determine the acute toxicity to Artemia franciscana nauplii of several PAHs at their respective solubility limits. Second, passive dosing was applied to recreate the seawater mixture composition of PAHs measured in a Spanish monitoring program, to test the toxicity of this mixture at different levels. HPLC analysis was used to confirm the reproducibility of the dissolved exposure concentrations for the individual PAHs and mixtures. This study shows that passive dosing has some important benefits in comparison with solvent spiking for testing HOCs in aquatic media. These include maintaining constant exposure concentrations, leading to higher reproducibility and a relative increase in toxicity. Passive dosing is also able to faithfully reproduce real mixtures of HOCs such as PAHs, in toxicity tests, reproducing both the levels and proportions of the different compounds. This provides a useful approach for studying the toxicity of environmental mixtures of HOCs, both with a view to investigating their toxicity but also for determining safety factors before such mixtures result in detrimental effects. PMID:22609739

Rojo-Nieto, E; Smith, K E C; Perales, J A; Mayer, P

2012-04-19

373

Application of leaching tests for toxicity evaluation of coal fly ash.  

PubMed

The toxic properties of coal fly ash samples obtained from various coal combustion power plants were evaluated in this work using physicochemical analyses and bioassays. Physicochemical analyses showed that heavy metals present in solid samples included Cr, Cu, Mn, Ni, Pb, and Zn. The results of the chemical analysis of eluates deduced by the application of standard leaching tests according to EN 12457-2 and Toxicity Characteristic Leaching Procedure (TCLP) methods indicated that the compounds contained in fly ashes could potentially be transferred to the liquid phase depending upon the leaching method used. Heavy metal concentrations were higher in TCLP eluates, indicating that the initial pH value of the leaching medium significantly affected the transfer of these elements to the liquid phase. Tests conducted with the photobacterium Vibrio fischeri (Microtox test), the crustacean Daphnia magna, and the rotifer Brachionus calyciflorus were used to assess toxicity of eluates obtained by both leaching tests. Daphnia magna was the most sensitive test organism. The EN 12457-2 method proved to be more reliable for toxicity evaluation of eluates. In contrast, the TCLP method showed some interference owing to acetic acid toxicity, and precipitation occurred after pH adjustment of eluates from acid to neutral range. The toxicity of both fly ashes and the corresponding solid leaching residues of EN 12457-2 and TCLP leaching tests was also measured using the Microtox Basic Solid phase Test. The results generated with this bioassay indicated that toxicity was greatly influenced by the pH status of the solid samples. PMID:16841327

Tsiridis, V; Samaras, P; Kungolos, A; Sakellaropoulos, G P

2006-08-01

374

Application of leaching tests for toxicity evaluation of coal fly ash  

SciTech Connect

The toxic properties of coal fly ash samples obtained from various coal combustion power plants were evaluated in this work using physicochemical analyses and bioassays. Physicochemical analyses showed that heavy metals present in solid samples included Cr, Cu, Mn, Ni, Pb, and Zn. The results of the chemical analysis of eluates deduced by the application of standard leaching tests according to EN 12457-2 and Toxicity Characteristic Leaching Procedure (TCLP) methods indicated that the compounds contained in fly ashes could potentially be transferred to the liquid phase depending upon the leaching method used. Heavy metal concentrations were higher in TCLP eluates, indicating that the initial pH value of the leaching medium significantly affected the transfer of these elements to the liquid phase. Tests conducted with the photobacterium Vibrio fischeri (Microtox test), the crustacean Daphnia magna, and the rotifer Brachionus calyciflorus were used to assess toxicity of eluates obtained by both leaching tests. Daphnia magna was the most sensitive test organism. The EN 12457-2 method proved to be more reliable for toxicity evaluation of eluates. In contrast, the TCLP method showed some interference owing to acetic acid toxicity, and precipitation occurred after pH adjustment of eluates from acid to neutral range. The toxicity of both fly ashes and the corresponding solid leaching residues of EN 12457-2 and TCLP leaching tests was also measured using the Microtox Basic Solid phase Test. The results generated with this bioassay indicated that toxicity was greatly influenced by the pH status of the solid samples.

Tsiridis, V.; Samaras, P.; Kungolos, A.; Sakellaropoullos, G.P. [Technological Educational Institute for West Macedonia, Kozani (Greece). Dept. for Pollution Control Technology

2006-08-15

375

Individual and combined developmental toxicity assessment of bisphenol A and genistein using the embryonic stem cell test in vitro.  

PubMed

The potential developmental toxicity of environmental estrogenic endocrine disruptors have become a great concern in recent years. In this study, two typical environmental oestrogen, namely, bisphenol A (BPA) and genistein (GEN) were investigated for potential embryotoxicity using the embryonic stem cell test model. Afterwards, a 4×4 full factorial design and the estimated marginal means plot were performed to assess the combined effects of these two compounds. According to the linear discriminant functions and classification criteria, bisphenol A and genistein were classified as weakly embryotoxic and strongly embryotoxic respectively. As for combined effects, the overall interaction between BPA and GEN on embryonic stem cells (ESCs) differentiation was synergistic at low dosages, however, on ESCs and 3T3 cell proliferation, the predominate action was additive. Considering the actual daily intake of these chemicals, it is concluded that BPA alone might not have adverse reproductive or developmental effects on human being. However, given that BPA and GEN do have synergistic effect at low concentration, they may disturb normal embryo development together, which could result in birth defect and behavioral alterations later in life. PMID:23948354

Kong, Dan; Xing, Lina; Liu, Ran; Jiang, Jianjun; Wang, Wanyi; Shang, Lanqin; Wei, Xuetao; Hao, Weidong

2013-08-12

376

An evaluation of nickel toxicity to Ceriodaphnia dubia and Daphnia magna in a contaminated stream and in laboratory tests  

Microsoft Academic Search

Seven-day tests with Ceriodaphnia dubia were used to document ambient toxicity in two industrially contaminated streams in southeastern Tennessee. Low survival of Ceriodaphnia dubia was linked to concentrations of Ni below EPA water quality criteria. A toxicity identification evaluation consisting of Ceriodaphnia dubia, Daphnia magna, and Pimephales promelas toxicity tests with Ni, chemical analyses, and experiments with a Ni-selective resin

Lynn Adams Kszos; Arthur J. Stewart; Paul A. Taylor

1992-01-01

377

EPAâ??s ToxCast Program for Predicting Toxicity and Prioritizing Chemicals for Further Screening and Testing  

EPA Science Inventory

Testing of environmental and industrial chemicals for toxicity potential is a daunting task because of the wide range of possible toxicity mechanisms. Although animal testing is one means of achieving broad toxicity coverage, evaluation of large numbers of chemicals is challengin...

378

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...during testing. Any food utilized should support survival, growth and reproduction of the mysids. A recommended food is live Artemia spp. nauplii (approximately 48 hours old). (2) Facilities â(i) Apparatus. (A) Facilities which may be...

2010-07-01

379

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...during testing. Any food utilized should support survival, growth and reproduction of the mysids. A recommended food is live Artemia spp. nauplii (approximately 48 hours old). (2) Facilities â(i) Apparatus. (A) Facilities which may be...

2009-07-01

380

Marine microalgae toxicity test for linear alkylbenzene sulfonate (LAS) and alkylphenol ethoxylate (APEO)  

Microsoft Academic Search

Different microalgal species have been used in growth-inhibition tests to determine the toxic concentrations of anionic and non-ionic surfactants to phytoplankton. The species used were selected from different taxonomic groups, all of considerable ecological relevance to marine environments. The toxicity of the C13 LAS homologue to the microalgal species selected was usually one order of magnitude greater than that of

I. Moreno-Garrido; M. Hampel; L. M. Lubián; J. Blasco

2001-01-01

381

Tracheal epithelium in culture: A model for toxicity testing of inhaled molecules  

SciTech Connect

Rabbit trachea primary cultures have been developed as a model to evaluate the toxicity of noxious airborne pollutants. A mucociliary epithelium has been restored in vitro on collagen gel. Several general cytotoxicity assays (viability and growth inhibition) permit a first assessment for the acute toxicity of the tested molecules. More specific criteria such as measurement of the integrity of the epithelial barrier and inhibition of ciliary beat frequency allow to determine a specific impact of xenobiotics on the mucociliary epithelium in culture.

Romet-Haddad, S.; Marano, F.; Blanquart, C.; Baeza-Squiban, A. (Universite Paris (France))

1992-07-01

382

Comparative Toxicity of Chlordane, Chlorpyrifos, and Aldicarb to Four Aquatic Testing Organisms  

Microsoft Academic Search

.   Laboratory toxicity data contrasting responses of aquatic organisms to insecticides are important for focusing on sensitive\\u000a species (steepest exposure-response slope) exposed to aqueous concentrations of these insecticides in field studies. These\\u000a data also allow prediction of expected responses of aquatic species to a range of insecticide concentrations in situ. Aqueous 48-h toxicity tests were performed to contrast responses of

M. T. Moore; D. B. Huggett; C. M. Cooper

1998-01-01

383

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

SciTech Connect

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

Not Available

1993-01-01

384

Correlation of the five test methods to assess chemical toxicity and relation to physical properties  

SciTech Connect

Biological tests using Orizias latipes (LC50 and oxygen uptake test), Moina macrocopa (LC50), and Dugesia japonica (head regeneration test and LC50) were carried out in order to clarify the mutual relationship of these test methods. The oxygen uptake rate of O. latipes was not effective to assess chemical toxicity. Adding the results of the growth inhibition test of Tetrahymena pyriformis (Yoshioka, Y., Ose, Y., and Sato, T. (1985). Sci. Total Environ. 43, 149-157), the correlation coefficients between each two test methods were calculated. The test results except EC50 and LC50 of D. japonica showed a good relation to each other. We determined the solubility and the n-octanol/water partition coefficient (P) of some chemicals used in the test. Log P interpreted the toxicity in mol/liter unit but not in mg/liter. Solubility was not a useful descripter neither in mol/liter nor in mg/liter unit.

Yoshioka, Y.; Ose, Y.; Sato, T.

1986-08-01

385

Rapid toxicity screening tests for aquatic biota. 1. Methodology and experiments with Daphnia magna  

SciTech Connect

A promising new and rapid toxicity screening test was developed, the concept and principles of which are presented. The method consists of visual observation of in vivo inhibition of an enzymatic process, using a fluorescent substrate. Juvenile Daphnia magna was exposed to a toxicant dilution series for 1 h, after which the substrate was added and the enzymatic inhibition was observed visually, using a long-wave UV light. The 1-h EC50 results of 11 pure compounds are presented and compared to the conventional 24- and 48-h Daphnia magna EC50s. All 1-h fluorescence EC50s were of the same order of magnitude and correlated very well with the 24- and 48-h EC50s. The sensitivity and reproducibility of this cost-effective screening test were compared to those of the Microtox[reg sign] test. The scope for application and the potential of this new rapid toxicity screening test are evaluated.

Janssen, C.R.; Persoone, G. (State Univ. of Ghent (Belgium))

1993-04-01

386

Dispersed oil toxicity tests with biological species indigenous to the Gulf of Mexico. Final report  

SciTech Connect

Static and flowthrough aquatic acute toxicity testing protocols were utilized on eggs and larvae of seven commercially important invertebrates and fishes from the Gulf of Mexico. Test organisms were exposed to Central and Western Gulf oils, dispersed oil, and Corexit 9527. Species included brown shrimp (Penaeus aztecus), white shrimp (Penaeus setiferus), blue crab (Callinectes sapidus), eastern oyster (Crassostrea virginica), red drum (Sciaenops ocellatus), inland silverside (Menidia berylina), and spot (Leiosomus xanthurus). Atlantic menhaden (Brevoortia tyrannus) was also tested because gulf menhaden were not available. Mysids (Mysidopsis bahia) were evaluated as part of a chronic toxicity assessment.

Fucik, K.W.; Carr, K.A.; Balcom, B.J.

1994-08-01

387

Dredged-material-effects assessment: Single-species toxicity/bioaccumulation and macrobenthos colonization tests  

SciTech Connect

Toxicity tests and bioaccumulation tests conducted according to methods established by the U.S. Environmental Protection Agency/Corps of Engineers in 1977 were used to evaluate potential environmental impacts of ocean disposal of dredged materials. Assessments of potential impacts based on results of currently recommended single-species tests were compared with results from macrobenthos colonization tests of dredged material from three harbors in the Gulf of Mexico and two in the Atlantic Ocean.

Parrish, P.R.; Moore, J.C.; Clark, J.R.

1989-01-01

388

Benefits and costs to mussels from ejecting bitterling embryos: a test of the evolutionary equilibrium hypothesis  

Microsoft Academic Search

Two major hypotheses of host-parasite interactions have been proposed to explain cases where hosts do not defend themselves against parasites. The evolutionary lag hypothesis suggests that there has been insufficient time for a host response to evolve, whereas the evolutionary equilibrium hypothesis proposes that host defence does not evolve because it carries costs that outweigh the benefits. We tested potential

Suzanne C. Mills; Martin I. Taylor; John D. Reynolds

2005-01-01

389

Towards tailored assays for cell-based approaches to toxicity testing.  

PubMed

The call for a new toxicology is mainly a call for cellular approaches and their computational integration. This article reflects on cell models, which are necessary to facilitate the transition. A mechanistic perspective has prompted the characterization of toxicity pathways and toxicity networks in order to develop robust cell-based assays for toxicity testing. Differing use scenarios for cell systems require higher degrees of sophistication, e.g., human-on-a-chip approaches are based on complex organotypic cultures to approximate the repertoire of human physiological reactions and high-throughput tests require simplicity and robustness. The new paradigm emerging under the branding of Toxicology for the 21(st) Century needs complex models for pathway of toxicity identification and simpler assays for testing the perturbation of any given pathway. With increasing knowledge about underlying mechanisms, the needs for complexity and test specificity will change. Selective cell-based assays are desirable, especially for the detection of novel toxicants and biothreats. Examples from endocrine disruption, pyrogenicity, and especially shellfish toxin testing are used to illustrate such developments. PMID:23138507

Rossini, Gian Paolo; Hartung, Thomas

2012-01-01

390

Effects of Low Dissolved Oxygen on Organisms Used in Freshwater Sediment Toxicity Tests  

EPA Science Inventory

This manuscript describes the results of tests to determine the tolerance of three benthic organisms to reduced dissolved oxygen (DO). These three organisms are those recommended by EPA for use in toxicity testing of contaminated sediments. The results of the exposures indicate ...

391

SALINITY TOLERANCE OF DAPHNIA MAGNA AND POTENTIAL USE FOR ESTUARINE SEDIMENT TOXICITY TESTS  

EPA Science Inventory

Daphnia magna Straus, a common organism used for freshwater sediment toxicity tests, was evaluated to determine its tolerance to salinity and suitability for tests with estuarine water and sediments. Daphnids were exposed for 2 to 21 days to salinity in a variety of water-only te...

392

Toxicity Testing of Soil Samples from Joliet Army Ammunition Plant, Illinois.  

National Technical Information Service (NTIS)

Environmental toxicity testing and soil chemical analyses were performed as part of an ecological risk assessment of the Joliet Army Ammunition Plant (JAAP), Joliet, IL. Test soils were collected from six sites at the plant (a load and pack area, two open...

C. T. Phillips R. T. Checkai N. A. Chester R. S. Wentsel M. A. Major

1994-01-01

393

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

Microsoft Academic Search

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

Frenier

1997-01-01

394

APPROACH TO ENVIRONMENTAL RISK ASSESSMENT USING AVIAN TOXICITY TESTS (JOURNAL VERSION)  

EPA Science Inventory

Toxicity tests results are often condensed into a single endpoint (LC50) to facilitate their use in environmental management. The single number cannot distinguish between two tests with equal LC50s but dissimilar slopes at LC50 and it cannot describe the response at low and high ...

395

Perspectives on Validation of High-Throughput Assays Supporting 21st Century Toxicity Testing  

EPA Science Inventory

In vitro high-throughput screening (HTS) assays are seeing increasing use in toxicity testing. HTS assays can simultaneously test many chemicals but have seen limited use in the regulatory arena, in part because of the need to undergo rigorous, time-consuming formal validation. ...

396

Non-Animal Methodologies within Biomedical Research and Toxicity Testing  

Microsoft Academic Search

Summary Laboratory animal models are limited by scientific constraints on human applicability, and increasing regulatory restrictions, driven by social concerns. Reliance on laboratory animals also incurs marked - and in some cases, prohibitive - logistical challenges, within high-throughput chemical testing programmes, such as those currently underway within Europe and the US. However, a range of non-animal methodologies is available within

Andrew Knight

2008-01-01

397

40 CFR 797.1330 - Daphnid chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...species â(i) Selection. (A) The cladocerans, Daphnia magna or D. pulex, are the species to be used in this...A) During the test the daphnids shall be fed the same diet and with the same frequency as that used for...

2009-07-01

398

40 CFR 797.1330 - Daphnid chronic toxicity test.  

Code of Federal Regulations, 2010 CFR

...species â(i) Selection. (A) The cladocerans, Daphnia magna or D. pulex, are the species to be used in this...A) During the test the daphnids shall be fed the same diet and with the same frequency as that used for...

2010-07-01

399

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2013 CFR

...oxygen concentration, pH, temperature, salinity, the concentration of test substance...dissolved oxygen concentration temperature, salinity, and pH shall be measured at the beginning...temperature shall not exceed 1 °C, while salinity changes shall not exceed 5...

2013-07-01

400

40 CFR 797.1950 - Mysid shrimp chronic toxicity test.  

Code of Federal Regulations, 2013 CFR

...oxygen concentration, pH, temperature, salinity, the concentration of test substance...oxygen concentration, temperature, salinity, and pH shall be measured weekly in...temperature should not exceed 1 °C, while salinity changes should not exceed 5...

2013-07-01

401

40 CFR 797.1330 - Daphnid chronic toxicity test.  

Code of Federal Regulations, 2013 CFR

...a suggested rate is 5 to 7 mg food (either solids or algal cells, dry weight) per liter dilution water or test solution...demonstrated to be adequate for daphnid culture. They include algae, yeasts and a variety of mixtures. (B) Organisms should be...

2013-07-01

402

Toxics testing performance evaluation for GB and GD  

SciTech Connect

Residues resulting from demilitarization, treatment, cleanup, and testing of military chemical agents at Dugway Proving Ground (DPG), Utah, are currently listed as hazardous wastes by the State of Utah Department of Environmental Quality. The US Army Test and Evaluation Command believes that certain categories of waste generated at DPG are not hazardous. To demonstrate this, analytical methods capable of quantitatively measuring the concentrations of chemical agents, including GB and GD, in the different waste media must be available. Argonne National Laboratory has developed methods to analyze metal substrate, spent hypochlorite decontamination fluid, and soil matrices for GB and GD. These methods involve the use of sorbent cartridge preconcentration and thermal desorption combined with gas chromatography using flame photometric detection to achieve the desired sensitivity and specificity. This report describes the methods and presents results for these three common waste matrices. The test results indicate that these methods can be used to quantitatively determine concentrations of GB and GD in the low parts-per-billion range in all sample media tested.

O`Neill, H.J.; Schneider, J.F.; Brubaker, K.L.; Kimmell, T.A.; Anderson, A.W.

1997-10-01

403

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...Deathâ means the lack of reaction of a test organism to gentle...over a specified period of time. (4) âLoading...old) mysids. For each age class (juvenile or...can be obtained in less time. The age class which is...

2009-07-01

404

40 CFR 797.1930 - Mysid shrimp acute toxicity test.  

Code of Federal Regulations, 2010 CFR

...Deathâ means the lack of reaction of a test organism to gentle...over a specified period of time. (4) âLoading...old) mysids. For each age class (juvenile or...can be obtained in less time. The age class which is...

2010-07-01

405

Simultaneous Multiple Species Testing: Acute Toxicity of 13 Chemicals to 12 Diverse Freshwater Amphibian, Fish, and Invertebrate Families.  

National Technical Information Service (NTIS)

The test series developed methods for testing a compliment of aquatic organisms in a single test that satisfies the freshwater acute toxicity requirements for setting water quality criteria. Species tested included fathead minnows Pimephales promelas, rai...

G. W. Holcombe G. L. Phipps A. H. Sulaiman A. D. Hoffman

1987-01-01

406

Humic substances and the water calcium content change the toxicity of malachite green  

Microsoft Academic Search

Summary Laboratory experiments were conducted to test interactive effects of calcium(Ca 2+) content and the presence of humic substance (HS) on malachite green (MAG)-induced toxicity in fish embryos and larvae by means of a semistatic 144-h- embryo-larval-test with zebrafish (Danio rerio). Two kinds of reconstituted water samples were used to produce the test media by mixing salts into deionized water

T. Meinelt; M. Pietrock; A. Wienke; F. Völker

2003-01-01

407

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

PubMed

A challenge-facing hazard identification and safety evaluation of engineered nanomaterials being introduced to market is the diversity and complexity of the types of materials with varying physicochemical properties, many of which can affect their toxicity by different mechanisms. In general, in vitro test systems have limited usefulness for hazard identification of nanoparticles due to various issues. Meanwhile, conducting chronic toxicity/carcinogenicity studies in rodents for every new nanomaterial introduced into the commerce is impractical if not impossible. New toxicity testing systems which rely on predictive, high-throughput technologies may be the ultimate goal of evaluating the potential hazard of nanomaterials. However, at present, this approach alone is unlikely to succeed in evaluating the toxicity of the wide array of nanomaterials and requires validation from in vivo studies. This article proposes a paradigm for toxicity testing and elucidation of the molecular mechanisms of reference materials for specific nanomaterial classes/subclasses using short-term in vivo animal studies in conjunction with high-throughput screenings and mechanism-based short-term in vitro assays. The hazard potential of a particular nanomaterial can be evaluated by conducting only in vitro high-throughput assays and mechanistic studies and comparing the data with those of the reference materials in the specific class/subclass-an approach in line with the vision for 'Toxicity Testing in the 21st Century' of chemicals. With well-designed experiments, testing nanomaterials of varying/selected physicochemical parameters may be able to identify the physicochemical parameters contributing to toxicity. The data so derived could be used for the development of computer model systems to predict the hazard potential of specific nanoparticles based on property-activity relationships. PMID:21965171

Lai, David Y

2011-09-30

408

Movement disorder and neuromuscular change in zebrafish embryos after exposure to caffeine  

Microsoft Academic Search

Though caffeine is broadly distributed in many plants and foods, little is known about the teratogenic effects of caffeine during early embryonic development. Here, we used zebrafish as a model to test toxicity and teratogenicity since they have transparent eggs, making the organogenesis of zebrafish embryos easier to observe. When the exposure doses of caffeine were less than 150 ppm (17.5,

Yau-Hung Chen; Yi-Hui Huang; Chi-Chung Wen; Yun-Hsin Wang; Wei-Li Chen; Li-Chao Chen; Huey-Jen Tsay

2008-01-01

409

Improving the Value of Standard Toxicity Test Data in REACH  

Microsoft Academic Search

\\u000a Worldwide, environmental risk assessment strategies are based on the assumption that measuring direct effects of single substances,\\u000a using a few single species tests, in combination with safety factors correcting for extrapolation inconsistencies, can be\\u000a used to protect higher levels of biological organization, such as populations and even ecosystems. At the same time, we are\\u000a currently facing a range of pollution

Magnus Breitholtz; Elin Lundström; Ulrika Dahl; Valery Forbes

410

Relating results from earthworm toxicity tests to agricultural soil  

USGS Publications Warehouse

The artificial soil tests of the European Economic Community and of the Organization for Economic Cooperation produce data relating earthworm mortality to pesticide concentrations in soil under laboratory conditions. To apply these results to agricultural soils it is necessary to relate these concentrations to amounts of pesticide applied per area. This paper reviews the relevant published literature and suggests a simple relation for regulatory use. Hazards to earthworms from pesticides are suggested to be greatest soon after application, when the pesticides may be concentrated in a soil layer a few millimeters thick. For estimating exposure of earthworms, however, a thicker soil layer should be considered, to account for their movement through soil. During favorable weather conditions, earthworms belonging to species appropriate to the artificial soil test have been reported to confine their activity to a layer about 5 cm. If a 5-cm layer is accepted as relevant for regulatory purposes, then an application of 1 kg/ha would be equivalent to 1-67 ppm (dry) in the artificial soil test.

Beyer, W.N.

1992-01-01

411

Using biodynamic models to reconcile differences between laboratory toxicity tests and field biomonitoring with aquatic insects  

USGS Publications Warehouse

Aquatic insects often dominate lotic ecosystems, yet these organisms are under-represented in trace metal toxicity databases. Furthermore, toxicity data for aquatic insects do not appear to reflect their actual sensitivities to metals in nature, because the concentrations required to elicit toxicity in the laboratory are considerably higher than those found to impact insect communities in the field. New approaches are therefore needed to better understand how and why insects are differentially susceptible to metal exposures. Biodynamic modeling is a powerful tool for understanding interspecific differences in trace metal bioaccumulation. Because bioaccumulation alone does not necessarily correlate with toxicity, we combined biokinetic parameters associated with dissolved cadmium exposures with studies of the subcellular compartmentalization of accumulated Cd. This combination of physiological traits allowed us to make predictions of susceptibility differences to dissolved Cd in three aquatic insect taxa: Ephemerella excrucians, Rhithrogena morrisoni, and Rhyacophila sp. We compared these predictions with long-term field monitoring data and toxicity tests with closely related taxa: Ephemerella infrequens, Rhithrogena hageni, and Rhyacophila brunea. Kinetic parameters allowed us to estimate steady-state concentrations, the time required to reach steady state, and the concentrations of Cd projected to be in potentially toxic compartments for different species. Species-specific physiological traits identified using biodynamic models provided a means for better understanding why toxicity assays with insects have failed to provide meaningful estimates for metal concentrations that would be expected to be protective in nature. ?? 2007 American Chemical Society.

Buchwalter, D. B.; Cain, D. J.; Clements, W. H.; Luoma, S. N.

2007-01-01

412

An evaluation of the seven-day toxicity test with Americamysis bahia (formerly Mysidopsis bahia)  

SciTech Connect

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 and its derivatives are also used in toxicity identification evaluation (TIE), risk assessment, and other applications. To evaluate the relative sensitivity of three measurement endpoints (survival, growth, and fecundity), the authors analyzed results from 115 tests with effluents, organic or inorganic chemicals, and receiving waters suspected of being toxic. Controls for 78 of these achieved acceptable survival and growth. Fifty of these 78 tests also achieved acceptable control fecundity. In the 47 tests with significant effects, survival was the most sensitive response in 57%, fecundity in 30%, and growth in 30%. There was little duplication in responses. Improving pretest holding conditions by decreasing the maximum density from {approximately}20 to 10 animals/L and increasing the temperature from {approximately}26 C to a range of 26 to 27 C improved the growth and fecundity in controls. Although the percentage of tests achieving acceptable control survival and growth decreased from 93 to 86%, the percentage achieving acceptable fecundity in controls increased from 60 to 97%. Seasonal differences in fecundity were detected among control groups. Although variable, fecundity is often the most sensitive measure of response. The 7-d mysid test estimates the chronic toxicity of effluents most effectively when all three endpoints are used.

Lussier, S.M.; Kuhn, A.; Comeleo, R.

1999-12-01

413

A discussion of the impact of US chemical regulation legislation on the field of toxicity testing.  

PubMed

Proposals for revising the principal United States law governing industrial chemicals, the Toxic Substances Control Act, have been under consideration in the US Congress for the past several years, and some version of such legislation may be passed in the near future. Concurrently, a desire to move away from current testing methods for ethical, scientific, and practical reasons has led to multi-million dollar investments in in vitro and computational toxicology methods and programs. Legislative language has the potential to endorse this transition and facilitate its fruition, or conversely enshrine in vivo testing methods for the foreseeable future. New legislation also has the potential to substantially increase the numbers of animals used in toxicity tests in the near term. However, there are a number of policies that, used effectively, can reduce the overall number of animals used in new toxicity tests. We present recent legislative proposals in the context of current testing programs and discuss their potential impacts on animal use, test method innovation, and achievement of desired legislative objectives. Discussions like these are essential to judiciously select policies that reduce the use of animals in toxicity testing and protect human health and the environment. PMID:21624455

Sullivan, Kristie; Beck, Nancy; Sandusky, Chad; Willett, Catherine

2011-05-23

414

Feasibility study of the zebrafish assay as an alternative method to screen for developmental toxicity and embryotoxicity using a training set of 27 compounds  

Microsoft Academic Search

To anticipate to increased testing needs for reproductive toxicity and 3R approaches, we studied zebrafish embryo\\/larva as an alternative for animal testing for developmental toxicity and embryotoxicity and evaluated a training set of 27 compounds with a standardized protocol. The classification of compounds in the zebrafish embryo\\/larva assay, based on a prediction model using a TI (teratogenic index) cut-off value

Ingrid W. T. Selderslaghs; Ronny Blust; Hilda E. Witters

415

A limitation of the Microtox{reg_sign} test for toxicity measurements of nonionic surfactants  

SciTech Connect

Qualitative and quantitative analysis of the components of wastewaters is a necessary step towards determining the nature of aqueous effluents. However, toxicity levels of the effluents and receiving waters should also be determined to obtain a more comprehensive understanding of the effects the discharges may have on aquatic environments. The Microtox{reg_sign} test was successfully used to measure EC50 values of nonionic polyethoxylate surfactants. However, toxicity measurements of real samples that contain surfactants above a particular concentration, termed the critical toxicity concentration (CTC) are not valid. These samples require dilution before the test is performed, and because the relationship between toxicity and concentration is not linear above the CTC, the EC50 cannot be extrapolated back to give the toxicity of the original concentrated sample and a true estimation of toxicity is therefore not possible. This phenomenon may be related to the minimum surface tension requirement of the bacteria or other physical properties of the surfactant such as the tendency to assemble at interfaces and surfaces and the tendency to form micelles.

Sherrard, K.B.; Marriott, P.J.; McCormick, M.J. [Royal Melbourne Inst. of Tech. (Australia). Dept. of Applied Chemistry; Millington, K. [CSIRO, Belmont (Australia). Div. of Wool Technology

1996-07-01

416

The influence of different artificial soil types on the acute toxicity of carbendazim to the earthworm Eisenia fetida in laboratory toxicity tests  

Microsoft Academic Search

Field populations of earthworms have shown a varied response in mortality to the fungicide carbendazim, the toxic reference substance used in agrochemical field trials. The aim of this study was to determine the influence of soil conditions as a potential cause of this variation. Laboratory acute toxicity tests were conducted using a range of artificial soils with varying soil components

Sian R. Ellis; Mark E. Hodson; Philip Wege

2007-01-01

417

Screening the Toxicity of Ni, Cd, Cu, Ivermectin, and Imidacloprid in a Short-Term Automated Behavioral Toxicity Test with Tubifex tubifex (Müller 1774) (Oligochaeta)  

Microsoft Academic Search

A new automated online toxicity test for screening of short-term effects of chemicals is presented using the freshwater oligochaete Tubifex tubifex in the Multispecies Freshwater Biomonitor™ (MFB). Survival and locomotory behavior of the worms were observed during 24 h of exposure to metals (Cd, Cu, Ni), pesticides (Imidacloprid), and pharmaceuticals (Ivermectin). The LC50 values revealed increasing toxicity in the following

Almut Gerhardt

2009-01-01

418

Marine microalgae toxicity test for linear alkylbenzene sulfonate (LAS) and alkylphenol ethoxylate (APEO).  

PubMed

Different microalgal species have been used in growth-inhibition tests to determine the toxic concentrations of anionic and non-ionic surfactants to phytoplankton. The species used were selected from different taxonomic groups, all of considerable ecological relevance to marine environments. The toxicity of the C13 LAS homologue to the microalgal species selected was usually one order of magnitude greater than that of the C11 homologue. The toxicity of a commercial LAS mixture to different microalgal species was also checked. For this material and C. gracilis, cellular counting by means of a Neubauer chamber and by use of a flow cytometer were compared; differences between the two methods were insignificant. The toxicity of decaethoxylated nonylphenol non-ionic surfactant to C. gracilis was also checked; the EC50 value for this compound was 1.0 mg L(-1). PMID:11760055

Moreno-Garrido, I; Hampel, M; Lubián, L M; Blasco, J

2001-10-01

419

The silicon microphysiometer for testing ocular toxicity in vitro.  

PubMed

The silicon microphysiometer has been used for in vitro evaluation of the ocular irritancy potential of water soluble ingredients and formulations. This light-addressable potentiometric sensor detects changes in cell physiology by monitoring the rate at which cultured cells excrete their acidic products of metabolism. We have mainly determined the metabolic effect of 53 products (21 surfactants and 32 surfactant-based formulations). The related maximal average Draize score (MAS) were available from historical data and varied from 1.7 to 54. All of the Draize categories were represented. Murine fibroblastic cells (L929 clone) were exposed to increasing concentrations of the product for approximately 400 sec per dose. The MRD(50) (dose of product that decreased the metabolic rate of the cells by 50%) was determined by interpolation from a plot of metabolic rate versus test material concentration. Decreases in metabolic rate, as assessed by the MRD(50), occurred over a wide range of concentrations (40 mug/ml-200 mg/ml). The linear (Pearson) and rank (Spearman) correlation between in vivo (MAS) and in vitro (log MRD(50)) data were 0.91 and 0.89, respectively. This study indicates that the silicon microphysiometer method exhibits a high correlation with the Draize test for water-soluble raw materials and formulations and thus can be used as an in vitro screen for ocular irritation. PMID:20732235

Catroux, P; Rougier, A; Dossou, K G; Cottin, M

1993-07-01

420

Comparative marine toxicity testing: A cold-water species and standard warm-water test species exposed to crude oil and dispersant  

Microsoft Academic Search

There are many methods in current use for testing the toxicity of discharges to marine waters. For practical purposes, standard tests and species are commonly used. None of these standard test procedures or species are done with the cold seawater and species typical of northern latitudes. This paper reports the toxicity testing of oil and dispersed oil to a cold-water

Robert A. Perkins; Sara Rhoton; Christina Behr-Andres

2005-01-01

421

[Toxicity of BPA and TBBPA to Daphnia magna and zebrafish Brachydanio rerio].  

PubMed

Acute toxicity of BPA and TBBPA to Daphnia magna, zebrafish (Brachydanio rerio) and development effects of zebrafish embryo and zebrafish. The tested chemicals remarkably restrained the were studied, and safety assessment was also made to Daphnia magna mobilization of Daphnia magna, which may cause them death. 48 h EC50 values for D. magna were 8.91 and 0.69 mg x L(-1) respectively. In addition, the chemicals showed the toxicity effects on zebrafish, and 96 h LC50 values were 9.06 and 1.78 mg x L(-1) respectively. BPA and TBBPA remarkably retarded the development of zebrafish embryos, which may cause embryo abnormality and death. And the most sensitive toxicological endpoints to BPA and TBBPA were found, 72 h EC50 (malformation and embryo do not hatch) values were 2.90 and 0.14 mg x L(-1) respectively. The results showed that zebrafish embryo should be the most sensitive to the tested chemicals. The results indicated that BPA and TBBPA were the pollutants with high toxicity, in which TBBPA had the higher toxicity. BPA is a potential teratogen to zebrafish embryos, while TBBPA restrains embryo from hatch. PMID:17926411

Liu, Hong-Ling; Liu, Xiao-Hua; Wang, Xiao-Yi; Wang, Xiao-Rong; Yu, Hong-Xia

2007-08-01

422

Ecotoxicity of aged uranium in soil using plant, earthworm and microarthropod toxicity tests.  

PubMed

Discrepancies about probable no effect concentrations (PNEC) for uranium in soils may be because toxicity tests used freshly contaminated soils. This study used 3 soils amended with a range of uranium concentrations 10 years previously. The toxicity tests with northern wheatgrass (Elymus lanceolatus); earthworm (Eisenia andrei) were not affected below ~1,000 mg U kg(-1), and the soil arthropod Folsomia candida was not affected below ~350 mg U kg(-1). Survival of Orthonychiurus folsomi was diminished 20% (EC(20)) by ~85-130 mg U kg(-1), supporting a PNEC in the range of 100-250 mg U kg(-1) as derived previously. PMID:22033655

Sheppard, S C; Stephenson, G L

2011-10-28

423

Differential toxicity of Disperse Red 1 and Disperse Red 13 in the Ames test, HepG2 cytotoxicity assay, and Daphnia acute toxicity test.  

PubMed

Azo dyes are of environmental concern due to their degradation products, widespread use, and low-removal rate during conventional treatment. Their toxic properties are related to the nature and position of the substituents with respect to the aromatic rings and amino nitrogen atom. The dyes Disperse Red 1 and Disperse Red 13 were tested for Salmonella mutagenicity, cell viability by annexin V, and propidium iodide in HepG2 and by aquatic toxicity assays using daphnids. Both dyes tested positive in the Salmonella assay, and the suggestion was made that these compounds induce mainly frame-shift mutations and that the enzymes nitroreductase and O-acetyltransferase play an important role in the observed effect. In addition, it was shown that the presence of the chlorine substituent in Disperse Red 13 decreased the mutagenicity about 14 times when compared with Disperse Red 1, which shows the same structure as Disperse Red 13, but without the chlorine substituent. The presence of this substituent did not cause cytotoxicity in HepG2 cells, but toxicity to the water flea Daphnia similis increased in the presence of the chlorine substituent. These data suggest that the insertion of a chlorine substituent could be an alternative in the design of dyes with low-mutagenic potency, although the ecotoxicity should be carefully evaluated. PMID:20549607

Ferraz, E R A; Umbuzeiro, G A; de-Almeida, G; Caloto-Oliveira, A; Chequer, F M D; Zanoni, M V B; Dorta, D J; Oliveira, D P

2010-04-12

424

The applicability of acetylcholinesterase and glutathione S-transferase in Daphnia magna toxicity test  

Microsoft Academic Search

The most commonly used toxicity test worldwide is the acute Daphnia magna test. The relevance of acetylcholinesterase (AChE) and glutathione S-transferase (GST) activity in D. magna exposed to chromium, cadmium, and diazinon was evaluated in connection with this standard test. We found no link between enzyme activities and immobility. Concentrations of Cr6+ up to 280 ?g\\/L had no effect on

Anita Jemec; Damjana Drobne; Tatjana Tišler a; Biotechnical Faculty

425

Harmonization of Animal Clinical Pathology Testing in Toxicity and Safety Studies  

Microsoft Academic Search

Ten scientific organizations formed a joint international committee to provide expert recommendations for clinical pathology testing of laboratory animal species used in regulated toxicity and safety studies. For repeated-dose studies in rodent species, clinical pathology testing is necessary at study termination. Interim study testing may not be necessary in long-duration studies provided that it has been done in short-duration studies

Kurt Weingand; Geoff Brown; Robert Hall; Dai Davies; Kent Gossett; Doug Neptun; Trevor Waner; Toshiaki Matsuzawa; Paul Salemink; Wilhelm Froelke; Jean-Pierre Provost; Gianni Dal Negro; John Batchelor; Mamoru Nomura; Horst Groetsch; Alphons Boink; Jon Kimball; David Woodman; Malcolm York; Eva Fabianson-Johnson; Michel Lupart; Elsa Melloni

1996-01-01

426

Assessing the toxicity of contaminated soils using the nematode Caenorhabditis elegans as test organism  

Microsoft Academic Search

In this study, nine uncontaminated reference soils and 22 contaminated soils with different physico-chemical properties and contamination patterns were tested with a standardized toxicity test, using the nematode, Caenorhabditis elegans, as test organism. Fertility, growth and reproduction of C. elegans in the soils were compared with the exposure in standard soil Lufa St.2.2. C. elegans showed 100% fertility and a

S. Höss; S. Jänsch; T. Moser; T. Junker; J. Römbke

2009-01-01

427

Toxicity test of landfill leachate using Sarotherodon mossambicus (freshwater fish)  

SciTech Connect

Landfill leachate was collected in March and July, 1984, at the Gin Drinkers' Bay Landfill Site, and the properties of the two leachates were examined. The leachate collected in March contained higher contents of total solids, ammonia, and metals than that collected in July. The leachates were treated with EDTA (10(-3) M) and Al/sub 2/(SO/sub 4/)/sub 3/ (2 and 4 g/liter), alone and in combination. Addition of alum (2 g/liter) removed more than 60% of the phosphate content of the two leachates, and about 20 and 68% of total solids from leachates collected in March and July, respectively. Different concentrations of the leachates (untreated and alum-treated) were used to test the survival of tilapia, Sarotherodon mossambicus. The 96-hr LC50 for untreated leachates of March and July were 1.4 and 12%, respectively. The alum-treated leachates raised the 96-hr LC50 to 2.2 and 31.4%, accordingly.

Wong, M.H.

1989-04-01

428

Static renewal tests using Anodonta imbecillus (freshwater mussels). Anodonta imbecillis copper sulfate reference toxicant test, Clinch River-Environmental Restoration Program (CR-ERP)  

SciTech Connect

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

Simbeck, D.J.

1993-12-31

429

Chip-based liver equivalents for toxicity testing - organotypicalness versus cost-efficient high throughput.  

PubMed

Drug-induced liver toxicity dominates the reasons for pharmaceutical product ban, withdrawal or non-approval since the thalidomide disaster in the late-1950s. Hopes to finally solve the liver toxicity test dilemma have recently risen to a historic level based on the latest progress in human microfluidic tissue culture devices. Chip-based human liver equivalents are envisaged to identify liver toxic agents regularly undiscovered by current test procedures at industrial throughput. In this review, we focus on advanced microfluidic microscale liver equivalents, appraising them against the level of architectural and, consequently, functional identity with their human counterpart in vivo. We emphasise the inherent relationship between human liver architecture and its drug-induced injury. Furthermore, we plot the current socio-economic drug development environment against the possible value such systems may add. Finally, we try to sketch a forecast for translational innovations in the field. PMID:23722971

Materne, Eva-Maria; Tonevitsky, Alexander G; Marx, Uwe

2013-08-13

430

Development of a chronic sediment toxicity test for marine benthic amphipods  

SciTech Connect

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

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

1992-12-01

431

Method for toxicity test of titanium dioxide nanoparticles in ciliate protozoan Tetrahymena.  

PubMed

Titanium dioxide (TiO2) nanoparticles have a high surface-to-mass ratio and rapidly aggregate in water causing great difficulties for toxicity test exposed to aquatic organisms or other cell lines. This study uses a cell viability kit for routine toxicity test of TiO2 as well as other nanoparticles which accumulate in the aquatic environment. Tetrahymena immediately endocytoses TiO2 nanoparticles and stores them in food vacuoles until the particles undergo exocytosis as larger aggregates. However, during the process of endocytosis and exocytosis, TiO2 particles interfere with cell growth and consequently induce acute toxicity. It exerted high cell growth inhibition at 20 h incubation and induces significant cytotoxic effects. Surprisingly, the effect of TiO2 decreases at 40 h incubation, due to the recovery of cell growth and reduction of the cytotoxicity of the particles. PMID:23705610

Ud-Daula, Asad; Pfister, Gerd; Schramm, Karl-Werner

2013-01-01

432

Toxicity of copper salts is dependent on solubility profile and cell type tested.  

PubMed

Copper (Cu) is considered an essential metal for living organisms. However, disruption of Cu homeostasis is toxic and can lead to disorders such as Menkes and Wilson's diseases. The brain appears to be a vulnerable target organ. This study investigated the toxicity of Cu based on its solubility profile and cell type tested. Human A-172 (glioblastoma), SK-N-SH (neuroblastoma) and CCF-STTG1 (astrocytoma) cells were assessed after exposure to different concentrations (0.5-500?M) of copper sulfate (CuSO4) or copper (II) oxide (CuO). Since Cu is a redox active transition metal, we hypothesized that oxidative stress would be the main mechanism underlying cell toxicity. Therefore, cell viability was correlated with the extent of reactive oxygen species (ROS) formation. Cell viability decreased at the higher concentrations of the Cu salts and CuO was more toxic compared to CuSO4. The astrocytoma and glioblastoma cells were more vulnerable compared to the neuronal cells. Furthermore, it appears that oxidative stress only partially accounts for Cu-induced cell toxicity. Further studies are needed to better understand the unique susceptibility of glial cells and determine the physicochemical properties of insoluble Cu which accounts for its enhanced toxicity. PMID:23287045

Shaligram, Sonali; Campbell, Arezoo

2012-12-31