toxicity study Articles
-
A molecular method for assessing the effects of potential contaminants on the rate of zebrafish (Danio rerio) development
Monitoring expression of the developmentally regulated genes shh, sox2, and tnnt1 by reverse transcriptase polymerase chain reaction (RT‐PCR) allows determination of the rate of embryogenesis in zebrafish (Danio rerio) embryos without direct visual observation. The utility of combining this approach and morphological methods during toxicity studies was demonstrated with embryos developing at ...
-
Cellular uptake of nanoparticles as determined by particle properties, experimental conditions, and cell type
The increased application of nanoparticles (NPs) is increasing the risk of NPs being released into the environment. Although many toxicity studies have been conducted, the environmental risk is difficult to estimate, because uptake mechanisms are often not determined in toxicity studies. Here we review the dominant uptake mechanisms of NPs in cells, as well as the effect of NP properties, ...
-
A practical approach to determine dose metrics for nanomaterials
Doses of conventional chemical substances in toxicity studies are traditionally described by administered mass. For deriving toxic doses of nanomaterials, mass and chemical composition alone may not be an adequate description of the dose as particles with the same chemical composition can have completely different toxic mass doses, depending on properties such as particle size. Other dose ...
-
The relationship between total cholinesterase activity and mortality in four butterfly species
The relationship between total cholinesterase activity (TChE) and mortality in four butterfly species (great southern white [Ascia monuste], common buckeye [Junonia coenia], painted lady [Vanessa cardui], and julia butterflies [Dryas julia]) was investigated. Acute contact toxicity studies were conducted to evaluate the response (median lethal dose and TChE) of the four species following exposure ...
-
Newport Bay sediment toxicity studies
Untitled Document Newport Bay is an important southern California lagoon, with its upper and lower portions serving different uses. The ecological reserve in the upper bay protects one of the few remaining estuarine habitats in southern California for coastal wetlands wildlife and estuarine marine life. The developed lower bay is the focus of recreational boating and ...
-
How toxic is coal ash? A laboratory toxicity case study
Under a consent agreement among EPA and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity since many standard test species are more sensitive than resident species, thus could provide information useful to the rule‐making. However, few laboratory ...
-
Acute toxicity of herbicide formulations and chronic toxicity of technical grade trifluralin to larval green frogs (Lithobates clamitans)
Fewer toxicity studies have been performed on herbicides than on insecticides despite heavier use of herbicides and evidence of herbicide formulation toxicity to amphibians. We conducted acute and chronic toxicity tests with the herbicide trifluralin (2,6‐dinitro‐N,N‐dipropyl‐4‐(trifluoromethyl)aniline) on tadpoles. Herbicide formulations had lower median lethal concentrations than an insecticide ...
-
Ecotoxicology
The term ecotoxicology was coined by René Truhaut in 1969 who defined it as "the branch of toxicology concerned with the study of toxic effects, caused by natural or synthetic pollutants, to the constituents of ecosystems, animal (including human), vegetable and microbial, in an ...
-
A toxicokinetic study of specifically acting and reactive organic chemicals for the prediction of internal effect concentrations in Scenedesmus vacuolatus
The toxic potency of chemicals is determined well by using the internal effect concentration accounting for differences in toxicokinetic processes and mechanisms of toxic action. This present study examines toxicokinetics of specifically acting and reactive chemicals in the green algae Scenedesmus vacuolatus by using an indirect method. Concentration depletion in the exposure medium was ...
-
Publication of the report about evaluation of substances dossiers
REACH: evaluation of substances The recently published annual report concerns the activity of the Agency about the evaluation of substances. In 2013 the evaluation activity focused on the control of compliance for the registration dossiers of substances: overall ECHA controlled 1130 dossiers, exceeding the target of 5% of the total number of dossiers presented for the registration deadline of ...
By Selerant srl
-
Phototoxicity of TiO2 nanoparticles to zebrafish (Danio rerio) is dependent on life stage
Zebrafish embryos have been used increasingly to evaluate nanomaterial toxicity. The present study compared phototoxicity of TiO2 nanoparticles with zebrafish at 4 life stages (embryos, yolk‐sac larvae, free‐swimming larvae, and juvenile) under simulated sunlight using the 96‐h standard toxicity assay. Yolk‐sac larvae were found to be the most sensitive to TiO2 phototoxicity, suggesting that ...
-
Growth and reproductive effects from dietary exposure to Aroclor 1268 in mink (Neovison vison), a surrogate model for marine mammals
Polychlorinated biphenyls (PCBs) from the commercial mixture Aroclor 1268 were historically released into the Turtle‐Brunswick River Estuary (TBRE, southeastern Georgia, USA) from industrial operations. Sum PCBs (ΣPCBs) in blubber samples from TBRE bottlenose dolphins (Tursiops truncatus) have been reported at concentrations more than 10‐fold higher than those observed in dolphins from ...
-
EPA Announces Start of Voluntary Pilot Program to Reduce Animal Testing
On December 20, 2016, the U.S. Environmental Protection Agency (EPA) announced the start of a pilot program to evaluate the usefulness and acceptability of a mathematical tool (the GHS Mixtures Equation), which is used in the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). EPA states that the goal of the pilot program is to “evaluate the utility and ...
-
A NEW MEDIUM FOR CAENORHABDITIS ELEGANS TOXICOLOGY AND NANOTOXICOLOGY STUDIES, DESIGNED TO BETTER REFLECT NATURAL SOIL SOLUTION CONDITIONS
A new toxicity test medium for C. elegans is presented. The test solution is designed so that it provides a better representation of natural soil pore water conditions than currently available test media. The medium has a composition that can readily be modified to allow for studies of the influences of a range of environmentally relevant parameters on nematode biology and toxicology. Tests ...
-
A toxicokinetic and toxicodynamic model approach of Myriophyllum spicatum to predict effects caused by short‐term exposure to a sulfonylurea
Toxicokinetic and toxicodynamic models are a promising tool to address the effects of time‐variable chemical exposure. While standard toxicity tests rely, in most cases, on static concentrations, these chemical exposure patterns are unlikely to appear in the field, where time‐variable exposure of chemicals is typical. In this study, we integrated toxicodynamic processes into an existing model ...
-
REACHing Asia: Recent trends in chemical regulations of China, Japan and Korea
Will EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemical substances) influence and change the chemical regulatory systems of Asia, as EU RoHS has done in China, Japan and Korea? The answer is YES. China, Japan and Korea are (or will be) filling the regulatory gap they see between REACH and their chemical regulatory systems. With its advanced chemical regulatory system ...
-
Insights into the nature of uranium target proteins within zebrafish gills after chronic and acute waterborne exposures
New data on the nature of the protein targets of U within the zebrafish gills were collected after waterborne exposure to better understand uranium (U) toxicity mechanisms. This study evidenced some common characteristics of the U protein target binding properties such as their role in other essential metals regulation and their phosphorus content. In total 21 potential protein targets, ...
-
Nanodrug potential in cancer therapy: efficacy/toxicity studies in cancer cells
The interest of nanotechnology to find a more effective approach for drug delivery is growing fast. Nanoparticles as drug vehicles potentially improve the pharmacokinetic and pharmacodynamic properties of various types of drugs, and provide a tool to visualise molecules and tumour target cells that otherwise cannot be detected through conventional imaging. However, there are many aspects of ...
-
Stepwise information‐filtering Tool (SIFT): A method for using risk assessment metadata in a nontraditional way
Tools exist to evaluate large ecotoxicity databases for risk assessment purposes, but are less useful for alternative analytical purposes. This study 1) developed the Strategic Information‐Filtering Tool (SIFT), a stepwise method to select relevant, reliable data from a large ecotoxicity database; 2) demonstrated utility in a case study of chronic toxicity data for statistical endpoint ...
-
Small concerns: Nanoscale materials as CECs
Products are being designed, tested and sold today tluit make use of nanoscale materials and nanoscale properties. The more commonly discussed applications include nanoscale electronics, more efficient water and wastewater membranes, and other materials with tailor-made physical properties (such as weight, strength, etc.) unavailable by their 'macro' counterparts. Due to the explosive growth of ...
Need help finding the right suppliers? Try XPRT Sourcing. Let the XPRTs do the work for you