Qualitative toxicity assessment of silver nanoparticles on the fresh water bacterial isolates and consortium at low level of exposure concentration.

Silver nanoparticles (AgNPs) pose a high risk of exposure to the natural environment owing to their extensive usage in various consumer products. In the present study we attempted to understand the harmful effect of AgNPs at environmentally relevant low concentration levels (≤1ppm) towards two different freshwater bacterial isolates and their consortium. The standard plate count assay suggested that the AgNPs were toxic towards the fresh water bacterial isolates as well as the consortium, though toxicity was significantly reduced for the cells in the consortium.

Different modes of TiO2 uptake by Ceriodaphnia dubia: relevance to toxicity and bioaccumulation.

The extensive environmental exposure of engineered metal oxide nanoparticles (NPs) may result in their bioaccumulation in aquatic organisms leading to their biotransfer in a food chain through various routes in a freshwater ecosystem. The present study focuses on the possible modes of TiO2 NP trophic transfer to Ceriodaphnia dubia, in presence and/absence of its diet, Scenedesmus obliquus (primary producer). The acute exposure studies (48h) were designed to have daphnids exposed to (i) the free NPs, (ii) both the free and the algae-borne NPs; and (iii) only the algae-borne NPs in separate tests to understand the possible routes of NP transfer.

Trophic transfer potential of aluminium oxide nanoparticles using representative primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia).

The transfer of nanoparticles through the food chain can lead to bioaccumulation and biomagnification resulting in a long term negative impact on the ecosystem functions. The primary objective of this study was evaluation of aluminium oxide nanoparticles transfer from primary producers to primary consumers. A simple set up consisting of a primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia) was used.

In vivo genotoxicity assessment of titanium dioxide nanoparticles by Allium cepa root tip assay at high exposure concentrations.

The industrial production and commercial applications of titanium dioxide nanoparticles have increased considerably in recent times, which has increased the probability of environmental contamination with these agents and their adverse effects on living systems. This study was designed to assess the genotoxicity potential of TiO2 NPs at high exposure concentrations, its bio-uptake, and the oxidative stress it generated, a recognised cause of genotoxicity. Allium cepa root tips were treated with TiO2 NP dispersions at four different concentrations (12.

Toxic effect of Cr(VI) in presence of n-TiO2 and n-Al2O3 particles towards freshwater microalgae.

The reactivity and toxicity of the soluble toxicants in the presence of the engineered nanomaterials is not well explored. In this study, the probable effects of TiO2 and Al2O3 nanoparticles (n-TiO2, n-Al2O3) on the toxicity of Cr(VI) were assessed with the dominant freshwater algae, Scenedesmus obliquus, in a low range of exposure concentrations (0.05, 0.

Ceriodaphnia dubia as a potential bio-indicator for assessing acute aluminum oxide nanoparticle toxicity in fresh water environment.

Growing nanomaterials based consumer applications have raised concerns about their potential release into the aquatic ecosystems and the consequent toxicological impacts. So environmental monitoring of the nanomaterials in aqueous systems becomes imperative. The current study reveals the potential of Ceriodaphnia dubia (C.

Cytotoxicity of TiO₂ nanoparticles and their detoxification in a freshwater system.

In the current study, two aspects concerning (i) the cytotoxicity potential of TiO₂ nanoparticles (NPs) toward freshwater algal isolate Scenedesmus obliquus and (ii) the potential detoxification of NPs by the microalgae were assessed under light (UV-illumination) and dark conditions at low exposure levels (≤1 μg/mL), using sterile freshwater as the test medium. The statistically significant reduction in cell viability, increase in reactive oxygen species production and membrane permeability (light vs. dark) suggested photo-induced toxicity of TiO₂ NPs.

Acute toxicity of TiO2 nanoparticles to Ceriodaphnia dubia under visible light and dark conditions in a freshwater system.

The ever increasing industrial and consumer applications of titanium dioxide nanoparticles (TiO2 NPs) raise concern over the possible risk associated with their environmental exposure. Still, the knowledge regarding nanoparticle behavior in a freshwater ecosystem is lacking. The current study focuses on the toxicity of TiO2 NPs towards Ceriodaphnia dubia (a dominant daphnid isolated from the freshwater) under two different conditions; (1) light and dark photoperiod (16:8 h) and (2) continuous dark conditions, for a period of 48 h.

Cytotoxicity of aluminium oxide nanoparticles towards fresh water algal isolate at low exposure concentrations.

The growing commercial applications had brought aluminium oxide nanoparticles under toxicologists' purview. In the present study, the cytotoxicity of two different sized aluminium oxide nanoparticles (ANP(1), mean hydrodynamic diameter 82.6±22nm and ANP(2), mean hydrodynamic diameter 246.

A temporal study on fate of Al2O3 nanoparticles in a fresh water microcosm at environmentally relevant low concentrations.

This study on a microcosm, brings out the temporal changes in physico-chemical behavior of aluminum oxide nanoparticles (for a period of 210 days), at environmentally relevant concentrations (1000 μg/L and below). The dynamics of particle behavior in terms of mean hydrodynamic diameter, specific surface area and dissolution of soluble aluminum and, their possible ecological implications have been presented in this study. A thorough statistical analysis brings out nanoparticle behavior, where a rapid aggregation of particles (79±13 nm at 0 h to 1464±80 nm at 48 h), with a decrease in specific surface area (32 m2/g at 0 h to 1.

Cytotoxicity of Al2O3 nanoparticles at low exposure levels to a freshwater bacterial isolate.

The cytotoxicity of Al(2)O(3) nanoparticles (NP) at very low exposure levels (1 μg/mL and less) to a dominant bacterial isolate from freshwater (lake water), Bacillus licheniformis, was examined. Sterile lake water was directly used as a test medium or matrix to simulate the freshwater environment. Exposure to 1 μg/mL Al(2)O(3) NP for 2 h caused a 17% decrease in cell viability (as determined by plate count and MTT assay).

Ecotoxicity study of titania (TiO₂) NPs on two microalgae species: Scenedesmus sp. and Chlorella sp.

In view of their increasing commercial applications metal oxide NPs like titania have elevated chances of entry to the environment. The ecotoxicity analyses are required to assess their environmental risks. The present work aims to demonstrate the effect of titania NPs on microalgae isolated from freshwater environment (Scenedesmus sp.