Acute and chronic toxicity of rare earth elements-enriched sediments from a prospective mining area: Effects on life history traits, behavioural and physiological responses of Gammarus fossarum (Crustacea Amphipoda).

Rare earth elements (REE) have an essential role and growing importance in the world's economy. They are attracting interest from society, policymakers, and scientists. The rapidly growing global demand for REE in several strategic industrial and agricultural sectors led many countries to consider the (re)-opening of mining activities for REE extraction.

Photodegradation of disposable polypropylene face masks: Physicochemical properties of debris and implications for the toxicity of mask-carried river biofilms.

COVID-19 outbreak led to a massive dissemination of protective polypropylene (PP) face masks in the environment, posing a new environmental risk amplified by mask photodegradation and fragmentation. Masks are made up of a several kilometres long-network of fibres with diameter from a few microns to around 20 µm. After photodegradation, these fibres disintegrate, producing water dispersible debris.

Lessons from linking bio- and ecological traits to stoichiometric traits in stream macroinvertebrates.

Ecologists rely on various functional traits when investigating the functioning of ecological systems and its responses to global changes. Changing nutrient levels, for example, can affect taxa expressing different trait combinations in various ways, e.g.

Continental-scale patterns of hyper-cryptic diversity within the freshwater model taxon Gammarus fossarum (Crustacea, Amphipoda).

Traditional morphological diagnoses of taxonomic status remain widely used while an increasing number of studies show that one morphospecies might hide cryptic diversity, i.e. lineages with unexpectedly high molecular divergence.

Microplastics enhance Daphnia magna sensitivity to the pyrethroid insecticide deltamethrin: Effects on life history traits.

The aim of the study was to investigate the influence of microplastics (MPs) on the ecotoxicity of common contaminants of aquatic ecosystems. As a model contaminant, the hydrophobic pesticide deltamethrin (DM) was chosen, and its effects on life history traits of Daphnia magna were studied in the presence or absence of polyethylene MPs. Commercialized DM and MPs obtained as dry powder were used in the experiment.

High food quality increases infection of Gammarus pulex (Crustacea: Amphipoda) by the acanthocephalan parasite Pomphorhynchus laevis.

Parasitism is an important process in ecosystems, but has been largely neglected in ecosystem research. However, parasites are involved in most trophic links in food webs with, in turn, a major role in community structure and ecosystem processes. Several studies have shown that higher nutrient availability in ecosystems tends to increase the prevalence of parasites.

High stoichiometric food quality increases moulting organism vulnerability to pollutant impacts: An experimental test with Gammarus fossarum (Crustacea: Amphipoda).

Headwater organisms are most often simultaneously faced with multiple stressors such as low resource quality and pollutants. Higher food quality has been hypothesized to enhance the tolerance of organisms to pollutants, but the interactive effects of food quality and pollutants on species and ecosystems remain poorly studied. To better understand these interactive effects, we experimentally manipulated the phosphorus (P) content of two leaf litters with contrasted carbon quality (alder and maple).

Combined acute ecotoxicity of malathion and deltamethrin to Daphnia magna (Crustacea, Cladocera): comparison of different data analysis approaches.

We studied the combined acute effect (i.e., after 48 h) of deltamethrin (a pyrethroid insecticide) and malathion (an organophosphate insecticide) on Daphnia magna.

Metal release from contaminated leaf litter and leachate toxicity for the freshwater crustacean Gammarus fossarum.

Industrialization has left large surfaces of contaminated soils, which may act as a source of pollution for contiguous ecosystems, either terrestrial or aquatic. When polluted sites are recolonized by plants, dispersion of leaf litter might represent a non-negligible source of contaminants, especially metals. To evaluate the risks associated to contaminated leaf litter dispersion in aquatic ecosystems, we first measured the dynamics of metal loss from leaf litter during a 48-h experimental leaching.

Additive effect of calcium depletion and low resource quality on Gammarus fossarum (Crustacea, Amphipoda) life history traits.

Gammarus fossarum is an often-abundant crustacean detritivore that contributes importantly to leaf litter breakdown in oligotrophic, mainly heterotrophic, headwater streams. This species requires large amounts of Ca to moult, thus allowing growth and reproduction. Because resource quality is tightly coupled to the organism's growth and physiological status, we hypothesised that low Ca concentration [Ca] and low food resource quality (low phosphorus [P] and/or reduced highly unsaturated fatty acid [HUFA] contents) would interactively impair molecular responses (gene expression) and reproduction of G.

Gammarus fossarum (Crustacea, Amphipoda) as a model organism to study the effects of silver nanoparticles.

Amphipods are one of the most important components of freshwater ecosystems. Among them, gammarids are the most widespread group in Europe and are often used as bioindicators and model organisms in ecotoxicology. However, their use, especially of Gammarus fossarum for the study of the environmental impact of nanoparticles, has been rather limited so far.

Integrated assessment of ceria nanoparticle impacts on the freshwater bivalve Dreissena polymorpha.

Exposures in realistic environmental conditions are essential to properly assess the effects of emerging pollutants on ecosystems. While ceria nanoparticles (nCeO2) production and use are expanding quickly, ecotoxicity studies remain very scarce. In this study, we set up experimental systems reproducing a simplified ecosystem to assess the effects of a chronic exposure to citrate-coated nCeO2 (ci-CeO2) and bare nCeO2 (ba-CeO2) on the freshwater mussel Dreissena polymorpha using an integrated multibiomarker approach.

Silver nanoparticles impact the functional role of Gammarus roeseli (Crustacea Amphipoda).

Silver nanoparticles (nAg) are widely used in consumer products and the risk associated with their potential release into freshwater ecosystems needs to be addressed using environmentally realistic exposure concentrations. Here, the effects of low concentrations (0.5-5 μg L(-1)) of two different sized nAg (10 and 60 nm) and a silver nitrate positive control were evaluated in Gammarus roeseli following exposure for 72 h.

Litter chemistry prevails over litter consumers in mediating effects of past steel industry activities on leaf litter decomposition.

Soil pollution has adverse effects on the performance and life history traits of microorganisms, plants, and animals, yet evidence indicates that even the most polluted sites can support structurally-complex and dynamic ecosystems. The present study aims at determining whether and how litter decomposition, one of the most important soil ecological processes leaf, is affected in a highly trace-metal polluted site. We postulated that past steel mill activities resulting in soil pollution and associated changes in soil characteristics would influence the rate of litter decomposition through two non-exclusive pathways: altered litter chemistry and responses of decomposers to lethal and sub-lethal toxic stress.

Multibiomarker assessment of cerium dioxide nanoparticle (nCeO2) sublethal effects on two freshwater invertebrates, Dreissena polymorpha and Gammarus roeseli.

Cerium nanoparticles (nCeO2) are widely used in everyday products, as fuel and paint additives. Meanwhile, very few studies on nCeO2 sublethal effects on aquatic organisms are available. We tried to fill this knowledge gap by investigating short-term effects of nCeO2 at environmentally realistic concentrations on two freshwater invertebrates; the amphipod Gammarus roeseli and the bivalve Dreissena polymorpha, using an integrated multibiomarker approach to detect early adverse effects of nCeO2 on organism biology.

Community structure and nutrient level control the tolerance of autotrophic biofilm to silver contamination.

Autotrophic biofilms are complex and fundamental biological compartments of many aquatic ecosystems. Since microbial species differ in their sensitivity to stressors, biofilms have long been proposed for assessing the quality of aquatic ecosystems. Among the many stressors impacting aquatic ecosystems, eutrophication and metal pollution are certainly the most common.

Investigation of differences in sensitivity between 3 strains of Daphnia magna (crustacean Cladocera) exposed to malathion (organophosphorous pesticide).

Acute and chronic ecotoxic effects of organophosphorous insecticide malathion (Fyfanon 50 EC 500 g L(-1)) were investigated on three strains of Daphnia magna. The nominal effective concentrations immobilizing 50% (EC50) of Daphnia after 24 and 48 h were 0.53 and 0.

Is acetylcholinesterase a biomarker of susceptibility in Daphnia magna (Crustacea, Cladocera) after deltamethrin exposure?

In the present study, we explored the possibility of using the acetylcholinesterase (AChE) as a biomarker after deltamethrin (pyrethroid insecticide) exposure with three strains of the cladoceran Daphnia magna. Four calculated time-weighted deltamethrin concentrations (20.1, 40.

Effect of deltamethrin (pyrethroid insecticide) on two clones of Daphnia magna (Crustacea, Cladocera): a proteomic investigation.

Deltamethrin is a class II pyrethroid insecticide commonly used in agriculture. It is hazardous to freshwater ecosystems, especially for the cladoceran Daphnia magna (Straus 1820). The results of our previous studies based on acute and chronic ecotoxicity experiments revealed differences in the sensitivity between two different clones.

Interactive effects of aluminium and phosphorus on microbial leaf litter processing in acidified streams: a microcosm approach.

Decline in pH, elevated aluminium (Al) concentrations, and base cations depletion often covary in acidified headwater streams. These parameters are considered as the main factors reducing microbial activities involved in detritus processing, but their individual and interactive effects are still unclear. In addition to its direct toxicity, Al can also reduce the bioavailability of phosphorus (P) in ecosystems through the formation of stable chemical complexes.

The contribution of a niche-based approach to ecological risk assessment: using macroinvertebrate species under multiple stressors.

We propose that a niche-based experimental approach at population level could be used to solve some uncertainties in traditional approaches in ecotoxicology. We tested this approach in the context of multiple stressors (i.e.

Phosphorus availability modulates the toxic effect of silver on aquatic fungi and leaf litter decomposition.

The functioning of forested headwater streams is intimately linked to the decomposition of leaf litter by decomposers, mainly aquatic hyphomycetes, which enables the transfer of allochthonous carbon to higher trophic levels. Evaluation of this process is being increasingly used as an indicator of ecosystem health and ecological integrity. Yet, even though the individual impacts of contaminants and nutrient availability on decomposition have been well studied, the understanding of their combined effects remains limited.

Behavioural and physiological responses of Gammarus fossarum (Crustacea Amphipoda) exposed to silver.

The study aims at investigating the effects of silver (Ag), a re-emerging contaminant, on physiological and behavioural responses in Gammarus fossarum. In a first experiment, G. fossarum Ag LC50s were evaluated during 96 h under semi-static mode of exposure.

Single and combined effects of cadmium and arsenate in Gammarus pulex (Crustacea, Amphipoda): understanding the links between physiological and behavioural responses.

This study aimed at investigating the individual and interactive effects of cadmium (Cd) and arsenate (AsV) in Gammarus pulex (Crustacea, Amphipoda) through the use of several biomarkers. Individuals were exposed for 240 h to two concentrations of AsV or Cd alone, and all the possible binary mixtures of these concentrations of AsV and Cd in a complete factorial design. The pattern of the biomarkers' responses to Cd and AsV alone or in mixture was similar in Gammarus pulex, even if the response intensity varied depending on the tested conditions.