Lethal and Sublethal Toxicity of Nanosilver and Carbon Nanotube Composites to -A Toxicogenomic Approach.

The increasing use of nanocomposites has raised concerns about the potential environmental impacts, which are less understood than those observed with individual nanomaterials. The purpose of this study was to investigate the toxicity of nanosilver carbon-walled nanotube (AgNP-CWNT) composites in . The lethal and sublethal toxicity was determined based on the characteristic morphological changes (retraction/loss of tentacles and body disintegration) for this organism.

Nanoplastic Contamination in Freshwater Biofilms Using Gel Permeation Chromatography and Plasmonic Nanogold Sensor Approaches.

The worldwide contamination of aquatic ecosystems by plastics is raising concern, including their potential impacts on the base of the food chain, which has been poorly documented. This study sought to examine, for the first time, the presence of nanoplastics (NPs) in biofilms from freshwater streams/rivers. They were collected at selected polluted sites, such as the industrial sector for plastic recycling and production, miscellaneous industries, agriculture, municipal wastewaters/effluents and road runoffs.

Plastic Analysis with a Plasmonic Nano-Gold Sensor Coated with Plastic-Binding Peptides.

Contamination with plastics of small dimensions (<1 µm) represents a health concern for many terrestrial and aquatic organisms. This study examined the use of plastic-binding peptides as a coating probe to detect various types of plastic using a plasmon nano-gold sensor. Plastic-binding peptides were selected for polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS) based on the reported literature.

Toxicity of two heavy rare earth elements to freshwater mussels Dreissena polymorpha.

Rare earth elements (REE) are essential components of many electronic devices that could end-up in solid waste disposal sites and inadvertently released in the environment. The purpose of this study was to examine the toxicity of two heavy REEs, erbium (Er) and lutetium (Lu), in freshwater mussels Dreissena polymorpha. Mussels were exposed to 14 days to increasing concentration (10, 50, 250, and 1250 µg/L) of either Er and Lu at 15 °C and analyzed for gene expression in catalase (CAT), superoxide dismutase (SOD), metallothionein (MT), cytochrome c oxidase (CO1), and cyclin D for cell cycle.

A nanogold sensor test for tire wear chemicals based on the plasmon ruler approach.

The release of tire wear substances in the environment is raising concerns about potential impacts on aquatic ecosystems. The purpose of this study was to develop a quick and inexpensive screening test for the following tire wear substances: 6-phenylphenyldiamine quinone (6-PPD quinone), hexamethoxymethylmelamine (HMMM), 1-3-diphenylguanidine (1,3-DPG), and melamine. A dual strategy consisting of nanogold (nAu) signal intensity and the plasmonic ruler principle was used based on the spectral shift from the unaggregated free-form nAu from 525 nm to aggregated nAu at higher wavelengths.

Micro and Nanoplastic Contamination and Its Effects on Freshwater Mussels Caged in an Urban Area.

Plastic-based contamination has become a major cause of concern as it pervades many environments such as air, water, sediments, and soils. This study sought to examine the presence of microplastics (MPs) and nanoplastics (NPs) in freshwater mussels placed at rainfall/street runoff overflows, downstream (15 km) of the city centre of Montréal, and 8 km downstream of a municipal effluent dispersion plume. MPs and NPs were determined using flow cytometry and size exclusion chromatography using fluorescence detection.

The Comet Assay, a Sensitive Biomarker of Water Quality Improvement Following Adoption of Beneficial Agricultural Practices?

Numerous actions have been undertaken by farmers to attenuate the impact of agricultural activities on aquatic ecosystems. The identification of biomarkers that respond quickly to water quality improvement could facilitate the assessment of adopted alternative practices and help maintain mobilization among stakeholders. We evaluated the potential of the comet assay, a biomarker of genotoxic effects, using a freshwater mussel, Elliptio complanata, as a model animal.

Comparative toxicity of micro and nanopolystyrene particles in Mya arenaria clams.

The contamination of coastal marine environments by plastics of sizes ranging from mm down to the nanoscale (nm) could pose a threat to aquatic organisms. The purpose of this study was to examine the toxicity of polystyrene nanoparticles (PsNP) of various sizes (50, 100 and 1000 nm) to the marine clams Mya arenaria. Clams were exposed to concentrations of PsPP for 7 days at 15 °C and analyzed for uptake/transformation, changes in energy metabolism, oxidative stress, genotoxicity and circadian neural activity.

Form-Dependent Toxicity of Silver Nanomaterials in Rainbow Trout Gills.

The toxicity of the form of nanoparticles is presently not well understood. The purpose of this study consists in comparing the toxicity of various forms of silver nanoparticles (nAg) in juvenile rainbow trout . Juveniles were exposed to various forms of polyvinyl-coated nAg of similar size for 96 h at 15 °C.

In vitro assessment of the genotoxicity and immunotoxicity of treated and untreated municipal effluents and receiving waters in freshwater organisms.

Municipal wastewater effluent is one of the largest sources of pollution entering surface waters in the Laurentian Great Lakes. Exposure to wastewater effluent has been associated with impaired immune systems and induction of genotoxicity to aquatic animals. Due to habitat degradation and environmental pollution linked to industrial development and population growth, several regions of the Great Lakes have been designated Areas of Concern (AOCs).

Investigation on the Toxicity of Nanoparticle Mixture in Rainbow Trout Juveniles.

The environmental impacts of nanoparticle mixtures in the aquatic environment is not well understood. The purpose of this study examined the sub-lethal toxicity of low concentrations (ug/L range) of selected nanoparticles alone and in mixtures in juvenile trout. Fish were exposed to to individual and two environmentally relevant mixtures of silver (nAg), copper oxide (nCuO) and cerium oxide (nCeO) nanoparticles for 96 h at 15 °C.

Shape-Dependent Toxicity of Silver Nanoparticles on Freshwater Cnidarians.

Silver nanoparticles (AgNPs) are increasingly used in various consumer products, leading to their inadvertent release in aquatic ecosystems. The toxicity of AgNPs could be associated with the leaching of ionic Ag but also with the size, shape and surface properties. The purpose of this study was to test the null hypothesis that toxicity of AgNPs was independent of shape in the invertebrate Hydra vulgaris.

Assessment of the toxicity of a mixture of five rare earth elements found in aquatic ecosystems in Hydra vulgaris.

Rare earth elements (REEs) are considered critical elements for technology and their extraction through mining activities is expected to increase in the future. Due to their chemical similarities, they often co-occur in minerals and thus their ecotoxicity should be assessed as a group/family. However, the available ecotoxicological studies focused mainly on the evaluation of the potential toxicological impacts of individual REEs rather than their mixtures.

Isolation and Quantification of Polystyrene Nanoplastics in Tissues by Low Pressure Size Exclusion Chromatography.

Ecotoxicity investigations of plastic nanoparticles (NPs) should pay more attention to their ability to pass barriers, accumulate, and initiate toxicity in cells. The purpose of this study was to develop a simple size exclusion chromatography (SEC) methodology to measure plastic NPs in biological tissues. A SEC column was prepared using a high-resolution gel for large macromolecules to separate plastic NPs from the protein/lipid pools in tissues.

Lanthanides Release and Partitioning in Municipal Wastewater Effluents.

The use of lanthanides is increasing in our society, whether in communication technologies, transportation, electronics or medical imaging. Some lanthanides enter urban wastewater and flow through municipal wastewater treatment plants (WWTPs). However, little is known about the effectiveness of treatment processes to remove these elements and the concentrations released in effluents to receiving waters.

Evaluation of uptake of the cytostatic methotrexate in Elliptio complanata mussels by LC-MS/MS.

Aquatic organisms are continuously exposed to emerging contaminants coming from urban effluents of wastewater treatment plants. The contamination of surface water by those effluents poses a number of environmental risks, and pharmaceuticals are part of this class of effluent contaminants. Various classes of pharmaceuticals are not treated by wastewater treatment plants and anticancer drugs are part of them.

Occurrence and size distribution of silver nanoparticles in wastewater effluents from various treatment processes in Canada.

The occurrence of silver (Ag) in urban effluents is partly associated with the increasing use of silver nanoparticles (Ag NPs) as an antiseptic agent in various consumer products. Distinction among Ag forms must be taken into account in the assessment of exposure and toxicological effects to aquatic organisms. Wastewater treatment processes effectively remove Ag particles and colloids (mostly > 95%), but this still leaves notable concentrations (in order of ng/L) escaping to effluent-receiving waters.

Occurrence and ecotoxicity of cytostatic drugs 5-fluorouracil and methotrexate in the freshwater unionid Elliptio complanata.

Municipal effluents continuously release cytostatic drugs with unknown consequences in aquatic organisms. The purpose of the study was to examine the sublethal toxicity of 2 commonly-found cytostatic drugs 5-fluouracile (5-FLU) and methotrexate (MTX) to endemic Elliptio complanata freshwater mussels. The mussels were exposed of each drugs at 0, 4, 20 and 100 μg/L for 96 h t 15 °C.

Toxicity of representative mixture of five rare earth elements in juvenile rainbow trout (Oncorhynchus mykiss) juveniles.

Rare earth elements (REEs) are contaminants of increasing interest due to intense mining activities for commercial purposes and ultimately released in the environment. We exposed juvenile rainbow trout (Oncorhynchus mykiss) to a representative mixture of the five most abundant REEs for 96 h at concentrations similar found in lakes contaminated by mining activities at 0.1, 1, 10, and 100X whereas the 1x mixture contained cerium (Ce, 280 μg/L), lanthanum (La, 140 μg/L), neodymium (Nd, 120 μg/L), praseodymium (Pr, 28 μg/L), and samarium (Sm, 23 μg/L).

Evaluation of general stress, detoxification pathways, and genotoxicity in rainbow trout exposed to rare earth elements dysprosium and lutetium.

Rare earth elements (REEs) have been recently identified as emergent contaminants because of their numerous and increasing applications in technology. The impact of REEs on downstream ecosystems, notably aquatic organisms, is of particular concern, but has to date been largely overlooked. The purpose of this study was thus to evaluate the toxicity of lanthanide metals, lutetium (Lu) and dysprosium (Dy) in rainbow trout after 96 h of exposure.

Crowding Effects of Polystyrene Nanoparticles on Lactate Dehydrogenase Activity in Hydra Attenuata.

Plastics pervade our environment and potentially release important quantities of plastic nanoparticles (NPs) from degradation in the environment. The purpose of this study was to examine the crowding effects of polystyrene NPs on lactate dehydrogenase (LDH) in vitro and following exposure to . First, LDH activity was measured in vitro in the presence of filamentous (F-)actin and NPs (50 and 100 nm diameter) to determine changes in viscosity and the fractal kinetics of LDH.

Biophysical effects of polystyrene nanoparticles on Elliptio complanata mussels.

The presence of nanoplastics (NPs) in various  products and from the weathering of released plastic materials are of concern for the environment's safety. The purpose of this study was to examine the biophysical effects of polystyrene NPs on freshwater mussels. Mussels were exposed to a range of concentrations of NPs (0.

Detection, biophysical effects, and toxicity of polystyrene nanoparticles to the cnidarian Hydra attenuata.

The occurrence of nanoplastic particles (NPs) in the environment has raised concerns about the ecotoxicological risk to aquatic ecosystems. The purpose of this study was to examine the bioavailability and toxicity of 50- and 100-nm transparent polystyrene NPs to the cnidarian Hydra attenuata. The hydras were exposed to increasing concentrations of 50- and 100-nm NPs (1.

Detection of polystyrene nanoplastics in biological samples based on the solvatochromic properties of Nile red: application in Hydra attenuata exposed to nanoplastics.

The release of nanoplastics (NP) from the weathering of microplastics is a major concern for the environment. Methods for the detection of NP in biological tissues are urgently needed because of their ability to penetrate not only in tissues but also in cells. A simple fluorescence-based methodology for the detection of polystyrene NP in biological tissues is proposed using the solvatochromic properties of Nile red.