scholarly journals Toxicity assessment of mining effluents using up-stream or reference site waters and test organism acclimation techniques

1997 ◽  
Author(s):  
Keyword(s):  
Reference Site ◽  
Test Organism ◽  
Toxicity Assessment

Oxidative stress and response of antioxidant system in Nostoc muscorum exposed to different forms of Zinc

2018 ◽  
Vol 43 (4) ◽  
pp. 352-361
Author(s):  
Sadaf Mahfooz ◽  
Sadaf Jahan ◽  
Adeeba Shamim ◽  
Arbab Husain ◽  
Alvina Farooqui
Keyword(s):  
Oxidative Stress ◽  
Assessment Tool ◽  
Test Organism ◽  
Toxicity Assessment ◽  
Nostoc Muscorum ◽  
Enzymatic Antioxidants ◽  
Stress Biomarkers ◽  
Low Concentrations ◽  
Toxicity Mechanisms ◽  
First Time

Abstract Objective Present study aims to evaluate oxidative stress-mediated toxicity mechanisms of nano-ZnO (N-ZnO) compared to ZnCl2 and bulk-ZnO (M-ZnO), using cyanobacterium as a toxicity assessment tool. Methods Nostoc muscorum was used as a test organism and the experiments were performed in parallels after treated with 2–128 μM of N-ZnO, M-ZnO, and ZnCl2. Results Low concentrations of ZnCl2 (2–8 μM) and N-ZnO (16–32 μM) led to a significant increase in the carotenoids, which could be ascribed to its role as an antioxidant, whereas higher concentrations were inhibitory to the photosynthetic pigments. Enhanced activities of superoxide dismutase (SOD), peroxidase (POD) and accelerated lipid peroxidation depicted significant accumulation of superoxide and peroxide radicals in N. muscorum exposed to N-ZnO and ZnCl2. The non-enzymatic antioxidants such as proline and total phenols also showed enhanced accumulations up to 16 and 64 μM of ZnCl2 and N-ZnO treatment, respectively. Conclusion Our results for the very first time depicted the significant accumulation of stress biomarkers in N. muscorum in response to deleterious effects of oxidative stress caused by N-ZnO, ZnCl2, and M-ZnO. Present results revealed varying levels of toxicity of various forms of zinc, which decreased in an order of ZnCl2>N-ZnO>M-ZnO.

TOXICITY ASSESSMENT OF ENGINEERED NANOPARTICLES USING ALGAE CHLORELLA VULGARIS

2017 ◽  
pp. 50-54
Author(s):  
A. A. Asanova ◽  
V. I. Polonskiy ◽  
Y. S. Grigoriev
Keyword(s):  
Chlorella Vulgaris ◽  
Photosynthetic Activity ◽  
Photosynthetic Apparatus ◽  
Test Organism ◽  
Toxicity Assessment ◽  
Delayed Fluorescence ◽  
Engineered Nanoparticles ◽  
Environmental Objects ◽  
Test Culture ◽  
Potential Risks

The use of nanoparticles covers new spheres of production every year. Their release into the environment is possible at any stage of their lifespan: from the manufacturing process to the utilization in the final product; therefore potential risks they pose for various environmental objects should be evaluated. The purpose of this work was to assess the effect of technogenic nanoparticles on Chlorella vulgaris growth and photosynthetic activity. Toxic properties of three types of nanoparticles TiO2 with a size of 100 to 190 nm, SiO2 with dimensions of 10-15 nm and 100-120 nm have been studied. Chlorella vulgaris Beijer alga was used as test organism. The evaluation of nanoparticles toxicity was based on changes in the relative delayed fluorescence index (RDFI), which characterizes the photosynthetic activity of microalgae. The effect on the growth of the test culture was determined from the optical density (OD) of the algal suspension. It was found that the TiO2 nanoparticles slightly reduced the growth and activity of the cell photosynthetic apparatus. Large particles of SiO2 proved to be more toxic than smaller ones. For nanoparticles of 100-120 nm size , the EC50 value according to the OD index was 8 mg/dm3, while the particles measuring 10-15 nm did not show a significant effect on the growth of the culture. Large SiO2 particles also appeared more toxic than small particles, judging by RDFI parameter.

Using Saccharomyces Cerevisiae for Toxicity Assessment including Interacting Effects and DNA Damage

1992 ◽  
Vol 25 (11) ◽  
pp. 309-316 ◽  
Author(s):  
A. Kungolos ◽  
I. Aoyama
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
Dna Damage ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Test Organism ◽  
Toxicity Assessment ◽  
Toxicity Screening ◽  
Suitable Index ◽  
Type Strains

Saccharomyces cerevisiae is used in this study not only as a test organism for routine quick toxicity screening but also as a potential indicator of DNA damage by chemicals. Several indices were investigated for evaluating the inhibition rates caused by some heavy metals. Specific growth rate proved to be the most suitable index. Of the chemicals used in this study CH3HgCl was the most toxic with an EC60of 3.5×10−4 mmol/l. The EC60's for HgCl2. CdCl2 and NiCl2 were 0.192, 0.0345 and 2.30 mmol/l respectively, using specific growth rate as an index. The interacting effect between Cd and Ni was generally additive. In order to detect DNA damage the growth of wild type strains was compared with the growth of strains deficient in one or all the DNA repairing systems. A known mutagen, 4-nitroquinoneline 1-oxide, and a non-mutagen, kanamycin, were used. The experimental results confirmed that 4-nitroquinoneline 1-oxide damaged the DNA of Saccharomyces cerevisiae, while kanamycin did not damage it. The importance of this confirmation lies in the fact that this test uses Saccharomyces cerevisiae, which is a eucaryotic organism and closer to human being than the procaryotic organisms that are usually used in other mutagenicity tests such as Ames test and Rec-assay.

Effect of carbofuran on quantitative and qualitative alterations in haemolymph of larva of Oryctes rhinoceros L. (Coleoptera: Scarabaeidae)

ENTOMON ◽  
2020 ◽  
Vol 44 (4) ◽  
pp. 293-300
Author(s):  
V.S. Salini
Keyword(s):  
Oral Route ◽  
Toxicity Assessment ◽  
Haematological Parameters ◽  
Oryctes Rhinoceros ◽  
Total Haemocyte Count ◽  
Differential Haemocyte Count ◽  
Third Instar Larvae

Investigation to evaluate the toxicity of carbofuran pesticides on haematological parameters of third instar larvae of Oryctes rhinoceros L. Indicated alterations in total haemocyte count and differential haemocyte count for toxicity assessment. Various doses of carbofuran (0.05g, 0.010g and 0.015 g) applied on insect through oral route and its impact after 24 hours of its application revealed that various doses of carbofuran exert specific alterations in both total and differential haemocytes of insect haemolymph.

Decolorization, Degradation and Subsequent Toxicity Assessment of Reactive Red 35 by Enterococcus gallinarum

2016 ◽  
Vol 5 (4) ◽  
pp. 325-336 ◽  
Author(s):  
Rakesh Soni ◽  
N.S. Bhatt ◽  
H.A. Modi ◽  
P.B. Acharya
Keyword(s):  
Toxicity Assessment ◽  
Enterococcus Gallinarum

Acute and Sub-acute Oral Toxicity Assessment of a Standardized Polyherbal Preparation POL-6 in Rats

2019 ◽  
Vol 9 (3) ◽  
pp. 207-216
Author(s):  
Lalit Sharma ◽  
Aditi Sharma ◽  
Girdhari L. Gupta ◽  
Gopal Singh Bisht
Keyword(s):  
Histopathological Examination ◽  
Safety Evaluation ◽  
Centella Asiatica ◽  
Toxicity Assessment ◽  
Ocimum Sanctum ◽  
Oral Toxicity ◽  
Significant Treatment ◽  
Body Weights ◽  
Total Body ◽  
Hematobiochemical Parameters

Background: A standardized polyherbal preparation (POL-6) containing six plant extracts Hypericum perforatum, Bacopa monnieri, Centella asiatica, Withania somnifera, Ocimum sanctum and Camellia sinesis have good antioxidant, anti-inflammatory, and immunomodulatory activities. The present study was carried out to evaluate the safety profile of POL-6 through acute and subacute oral toxicity models in Wistar rats. Methods: In acute safety evaluation, a single dose of 2000mg/kg of POL-6 was given orally to five rats and was observed for 14 days. In subacute safety evaluation POL-6 at the doses of 250, 500 and 1000 mg/kg was given orally to the rats once a day for 28 days. The animals were observed for the signs of toxicity and mortality during the study period. Results: In acute toxicity evaluation, POL-6 treatment did not show any toxic signs and mortality in animals during the observation period. In subacute toxicity studies, no changes were seen in any of the dose levels of POL-6 treatment during the total body weights, organ weights and hematobiochemical parameters examination of the rats. No lesions were seen during the gross/histopathological examination. Conclusion: The study revealed that administration of POL-6 for 28 days showed no significant treatment generated toxic effects in the animals, hence it can be considered as non-toxic if it is ingested in a time not greater than a month.

Real-life Field Studies of the NOx Removing Properties of Photocatalytic Surfaces in Roskilde and Copenhagen Airport, Denmark

2020 ◽  
Vol 01 ◽  
Author(s):  
Henrik Jensen ◽  
Pernille D. Pedersen
Keyword(s):  
Air Quality ◽  
High Stability ◽  
Reference Site ◽  
Real Life ◽  
Field Studies ◽  
The Real ◽  
Before And After ◽  
Parking Lot ◽  
Photocatalytic Concrete

Aims: To evaluate the real-life effect of photocatalytic surfaces on the air quality at two test-sites in Denmark. Background: Poor air quality is today one of the largest environmental issues, due to the adverse effects on human health associated with high levels of air pollution, including respiratory issues, cardiovascular disease (CVD), and lung cancer. NOx removal by TiO2 based photocatalysis is a tool to improve air quality locally in areas where people are exposed. Methods: Two test sites were constructed in Roskilde and Copenhage airport. In Roskilde, the existing asphalt at two parking lots was treated with TiO2 containing liquid and an in-situ ISO 22197-1 test setup was developed to enable in-situ evaluation of the activity of the asphalt. In CPH airport, photocatalytic concrete tiles were installed at the "kiss and fly" parking lot, and NOx levels were continuously monitored in 0.5 m by CLD at the active site and a comparable reference site before and after installation for a period of 2 years. Results: The Roskilde showed high stability of the photocatalytic coating with the activity being largely unchanged over a period of 2 years. The CPH airport study showed that the average NOx levels were decreased by 12 % comparing the before and after NOx concentrations at the active and reference site. Conclusion: The joined results of the two Danish demonstration projects illustrate a high stability of the photocatalytic coating as well as a high potential for improvements of the real-life air quality in polluted areas.

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