Research of nickel nanoparticles toxicity with use of Aquatic Organisms

The effect of nanoparticles with the particle size Δ50=5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Сhlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)С20 is determined for all the organisms used in bioassays. L(E)С50 is estimated for Paramecium caudatum (L(E)С50 = 0.0049 mg/l), for Сhlorella vulgaris Beijer (L(E)С50 = 0.529 mg/l), for Daphnia m. S (L(E)С50 > 100 mg/l) and for fish Danio rerio (L(E)С50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances

Embryotoxicity of poorly soluble nanoparticles at various stages of Zebrafish development

The biological effects of the poorly soluble nanoparticles (NPs) of different chemical nature and structural characteristics were evaluated. It was established that the Zebrafish test response to contamination of aqueous medium with nickel NPs (nNi), platinum (nPt), zinc oxide (nZnO) and cerium oxide (nCeO2) depends on the physicochemical properties of the NPs and embryo development stage. The concentrations of NPs not causing disruptions in embryonic development of Zebrafish were determined. The smallest impact on embryogenesis was exerted by nCeO2: coagulation of a small number of embryos was observed only at C = 20.0 mg/L. The same effect was observed when exposed to lower concentrations of nPt (C = 5.0 mg/L) and nNi (C = 0.1 mg/L). The greatest number of coagulated embryos was observed when grown in the DS nZnO: 37.5% of embryos died at the DS concentration of C = 0.1 mg/L. Zebrafish cultivation in the DS with low concentrations (C ≤ LC10) of nNi and nZnO caused distortions in the development of embryos: development of scoliosis, malformation of somites, inhibited mobility

Effect of AL2O3 and TiO2 nanoparticles on aquatic organisms

Environmental toxicity of aqueous disperse systems of nanoparticles of binary compounds of titanium dioxides (with particle size Δ50=5 nm, Δ50=50 nm, Δ50=90 nm), aluminum oxide alpha-forms (Δ50=7 nm and Δ50=70 nm) and macro forms (TiO2 Δ50=350 nm, Al2O3 Δ50=4000 nm) were studied using biological testing methods. The bioassay was performed using a set of test organisms representing the major trophic levels. We found the dependence of the toxic effect concentration degree of nTiO2 and nAl2O3 on the fluorescence of the bacterial biosensor "Ekolyum", the chemotactic response of ciliates Paramecium caudatum, the growth of unicellular algae Chlorella vulgaris Beijer and mortality of entomostracans Daphnia magna Straus. We revealed the selective dependence of nTiO2 and nAl2O3 toxicity on the size, concentration and chemical nature of nanoparticles. The minimal concentration causing an organism’s response on nTiO2 and nAl2O3 effect depends on the type of the test-organism and the test reaction under study. We specified L(E)С50 and acute toxicity categories for all the studied nanoparticles. We determined that nTiO2 (Δ50=5 nm) belong to the category «Acute toxicity 1», nTiO2 (Δ50=90 nm) and nAl2O3 (Δ50=70 nm) – to the category «Acute toxicity 2», nAl2O3 (Δ50=7 nm) - to the category «Acute toxicity 3». No acute toxicity was registered for nTiO2 (Δ50=50 nm) and macro form TiO2

Evaluation of the toxicity of superfine materials to change the physiological functions of aquatic organisms of different trophic levels

We assessed ecological and biological effects caused by the physical and chemical properties of nanomaterials on the basis of the laboratory researches into water test-organisms of different trophic levels. We studied the physiological functions of water organisms on adding into the environment superfine materials of various chemical nature and structural characteristics: metallic nanoparticles of nikel (nNi), argentum (nAg), platinum (nPt), aurum (nAu), binary NPs (powder of titanium dioxide - nТiO2, aluminum oxide - nAl2O3, zink oxide - nZnO, silicon nitride - nSi3N4, silicon carbide (nSiC) and carbon nanotubes (ВТ-50, MCD-material). We observed the dependence of developing the complex of unfavourable biological effects in water plants and entomostracans’ organisms on the physical and chemical properties of superfine materials. We determined the values of NOEC, L(E)С20 and L(E)С50 for aquatic organisms of various regular groups. We found out the most vulnerable elements of the communities’ trophic structure and the possibility of a breakdown in the water ecosystem food pyramid

Danger due to the translocation of nanoparticles in soil: mathematical modeling

A necessary step was taken towards the formation of a migration model of nanoparticles (NPs) from the surface deep into the soil, taking into account the frequency of precipitation and the processes of adsorption and desorption which occur in the soils. An equation for migration of nanoparticles in soil is proposed. A method of obtaining the averaged equations for long-term migration of NPs in the soil profile has been developed. Similarly, partial differential equations may be obtained which describe more complex models, for example, including capillary phenomena, etc. The obtained equations allow the use of integral transformations in order to find solutions. The model can be used to plan natural experiments in different types of soils

Effect of zink oxyde nanoparticles on the test function of water organisms of different trophic levels

The toxicity of zinc oxide nanoparticles (nZnO) with particle size Δ50 = 20 nm was evaluated according to the degree of toxicity of the aqueous disperse system (DS) with biological testing methods using a set of test organisms representing the major trophic levels.We observed the influence of the concentration degree of nZnO on toxic effects level on the fluorescence of the bacterial biosensor "Ekolyum-13", the chemotactic response of ciliates Paramecium caudatum, the rate of growth of unicellular algae Chlorella vulgaris Bayer, mortality of entomostracans Daphnia magna Straus and fish Danio rerio. The detected values of L(E)C50 are: for biosensor "Ekolyum-13" – 0.30 mg/L, for ciliates Paramecium caudatum – 0.14 mg/L, for Chlorella vulgaris Bayer – 0.17 mg/L and for Daphnia magna Straus – 0.52 mg/L. No toxicity of nZnO was detected in relation to fish Danio rerio, L(E)C50 > 100 mg/L. In assessing the maximum effect of nZnO according to GHS and EU Directive 93/67/ EEC, it is assigned to dangerous substances with a high degree of toxicity "Acute toxicity 1"

Phototropic response features for different systematic groups of mesoplankton under adverse environmental conditions

Current trends in the application of bioindication methods are related to the use of submersible tools that perform real- time measurements directly in the studied aquatic environment. The methods based on the registration of changes in the be- havioral responses of zooplankton, in particular Crustaceans, which make up the vast majority of the biomass in water areas, seem quite promising. However, the multispe- cies composition of natural planktonic biocenoses poses the need to consider the potential difference in the sensitivity of organisms to pollutants. This paper describes laboratory studies of the phototropic response of plankton to attracting light. The studies were carried out on a model natural community that in equal amounts includes Daphnia magna, Daphnia pulex, and Cyclops vicinus, as well as on the monoculture groups of these species. The phototropic response was initiated by the attracting light with a wavelength of 532 nm close to the local maximum of the reflection spectrum of chlorella microalgae. Standard potassium bichromate was used as the model pollutant

Effect of platinum nanoparticles on morphological parameters of spring wheat seedlings in a substrate-plant system

When wheat is cultivated in the media contaminated with platinum nanoparticles, the change in the morphological and physiological indexes of wheat seedlings depends on the physico-chemical parameters of the germination substrate. The changes become less pronounced with the decreasing bioaccessability of the nanomaterial in the following order: water suspension – luvisols – phaeozems. Contamination with nanoparticles affects the height parameters and activates the mechanisms protecting the plant from stress. When using wheat seedlings as test organisms for biotesting the environmental safety of NPs, it is advisable to use the following parameters: weight of roots, weight of aerial part, leaf area, and flavonoid content

Transfer of Pt marker nanoparticles in a three-link trophic chain chlorella Beijer-Daphnia magna Straus-Cyprinus carpio

The entrance of Pt marker nanoparticles (NPs) into the hydrosphere leads to association with unicellular algae Chlorella (the bioaccumulation factor reaches 10 000). There is a significant elimination time (t(1/2) = 7 days) even with single contamination of the hydrosphere. Pt NPs, entering the hydrosphere, accumulate in the organism Daphnia magna Straus in large numbers (bioaccumulation factor of 1000-2000), starting from the first day, which can be dangerous for consumers of a higher trophic level. The accumulation of NPs occurs both in the digestive tract and on the surface of the body (t(1/2) = 3 h). The accumulation of NPs during transmission through the food chain with chlorella contaminated with nanoparticles exceeds accumulation from the environment by 4 times, which is associated with the preliminary accumulation of NPs by food (chlorella) and absorption by Daphnia of NPs in a concentrated form. NPs accumulate in fish from the environment (bioaccumulation factor of up to 2500) and along the food chain (bioaccumulation factor of up to 350). Purification from NPs during accumulation along the food chain occurs much more slowly than in the series with the accumulation of NPs from the environment. When using fish products contaminated with NPs, such organs and tissues as skin, muscles and skeleton are of greatest risk