Project description:Microplastics represent a growing environmental concern for the oceans due to their potential capability to adsorb different classes of pollutants, thus representing a still unexplored source of exposure for aquatic organisms. In this study polystyrene (PS) microplastics were characterized for their capability to adsorb pyrene (PYR) as model compound for polycyclic aromatic hydrocarbons, and transfer this chemical to filter feeding mussels Mytilus galloprovincialis. Gene expression analyses of Mytilus galloprovincialis exposed to polystyrene (PS) microplastics and to polystyrene contaminated with pyrene (PS-PYR) have been performed trough a DNA microarray platform.
Project description:We introduce FACIL (http://www.cmbi.ru.nl/FACIL), a fast, reliable tool to evaluate nucleic acid sequences for non-standard codes that detects alternative genetic codes even in species distantly related to known organisms. Results are visualized in a Genetic Code Logo. To illustrate the use of our method, we analysed several contigs derived from the mitochondrial genome of the foraminifer Globobulimina pseudospinescens. These are particularly challenging data, as the genome is highly fragmented and incomplete. Approximately 10,000 single-cell Globobulimina pseudospinescens organisms were isolated by hand from Gullmar Fjord Sweden sediment. After washing, total DNA was extracted and sequenced by Illumina sequencing. The reads were assembled using Edena. To illustrate the use of our method, we analysed several contigs derived from the mitochondrial genome of the foraminifer Globobulimina pseudospinescens, an organism without any sequenced relatives in the databases. These are particularly challenging data, as the genome is highly fragmented and incomplete. DNA isolated from approximately 10,000 single-cell Globobulimina pseudospinescens organisms
Project description:High emission of tire rubber particles to the surrounding environment is an inevitable consequence of the current habits of transportation. Although most of the emissions stay within a close range of the sources, it has been proven that the smallest particles can be transported to remote locations through the atmosphere, including inland water bodies. It has been estimated that a relevant portion of the global emissions of tire rubber particles reach surface waters, but effects on aquatic life in the receiving water bodies are not completely understood. In the present study, we used the freshwater sediment dwellers Lumbriculus variegatus and Chironomus riparius to examine the toxicity of tire rubber particles at environmentally relevant concentrations, using different types of sediment and two particle sizes of tire rubber. Overall, the experiments were unable to discern any effects on the growth, survival or reproduction of the two animals tested. Significant differences were found among the animals dwelling on different sediments, but the effects were not attributable to the presence of tire rubber particles. This study provides important information regarding the lack of effect of tire rubber particles in laboratory experiments with model sediment dwellers and opens more questions about the potential effects of tire rubber particles in the real environment with longer durations and varying environmental factors. The influence of other factors such as the leaching of additives in the overall toxicity of tire rubber particles should be also considered.
Project description:We introduce FACIL (http://www.cmbi.ru.nl/FACIL), a fast, reliable tool to evaluate nucleic acid sequences for non-standard codes that detects alternative genetic codes even in species distantly related to known organisms. Results are visualized in a Genetic Code Logo. To illustrate the use of our method, we analysed several contigs derived from the mitochondrial genome of the foraminifer Globobulimina pseudospinescens. These are particularly challenging data, as the genome is highly fragmented and incomplete. Approximately 10,000 single-cell Globobulimina pseudospinescens organisms were isolated by hand from Gullmar Fjord Sweden sediment. After washing, total DNA was extracted and sequenced by Illumina sequencing. The reads were assembled using Edena. To illustrate the use of our method, we analysed several contigs derived from the mitochondrial genome of the foraminifer Globobulimina pseudospinescens, an organism without any sequenced relatives in the databases. These are particularly challenging data, as the genome is highly fragmented and incomplete.
Project description:Abstract: Nanoparticles (NPs) are expected to make their way into the aquatic environment where sedimentation of particles will likely occur, putting benthic organisms at particular risk. Therefore, organisms such as Hyalella azteca, an epibenthic crustacean which forages at the sediment surface, is likely to have a high potential exposure. Here we show that Zinc Oxide (ZnO) NPs are more toxic to H. azteca compared with the corresponding metal ion, Zn2+. Dissolution of ZnO NPs contributes about 50% of the Zn measured in the ZnO NP suspensions, and cannot account for the toxicity of these particles to H. azteca. However, gene expression analysis is unable to distinguish between the ZnO NP exposures and Zinc Sulfate (ZnSO4) exposures at equitoxic concentrations. These results lead us to hypothesize that ZnO NPs provide and an enhanced exposure route for Zn2+ uptake into H. azteca, and possibly other sediment dwelling organisms. Our study supports the prediction that sediment dwelling organisms are highly susceptible to the effects of ZnO NPs and should be considered in the risk assessment of these nanomaterials.
Project description:The pollution of the environment with microplastics has been recognized as an emerging threat worldwide. Due to an exponential increase in production of plastic over the last eight decades and its longevity in the environment, accumulating amounts of microplastic are polluting rivers, lakes and the ocean. Their entry pathways are diverse and still only incompletely understood. Since microplastics are usually defined smaller than 5 mm, it can be ingested by a wide range of aquatic organisms including teleost fish. There are different approaches to study the detrimental effects of pollutants on aquatic organisms. On the one hand, generic baseline parameters such as growth and mortality are regularly considered, often accompanied by established stress parameters such as cortisol, heat shock proteins or lipid oxidation. The conflicting findings to date suggest that these parameters might not be sensitive enough to indicate the physiological effects of environmentally relevant microplastic concentrations. For this reason, more sophisticated biological approaches could provide new insights into whether and how microplastics harm fish. To date, proteomic approaches have been used only sporadically when investigating the effects of microplastic exposure on aquatic organisms. So far, this approach has not been used to address potential microplastic impacts in fish. In the present study, a proteomic approach was trialed alongside established methods in an investigation of fish experiencing long-term exposure to environmentally relevant concentrations of microplastics. Two groups of rainbow trout (Oncorhynchus mykiss were exposed to microplastic concentrations and sizes currently encountered in wild fish and an increased concentration, expected to occur in the near future. These groups where compared to a control group maintained in MP free conditions. Five fish of each treatment were sampled at three time points (week 1, week 4, week 17). The experiments were performed in triplicates, resulting in 45 samples used in the proteomic analysis.
Project description:The contamination of marine ecosystems with microplastics, such as the polymer polyethylene, a commonly used component of single-use packaging, is of global concern. Although it has been suggested that biodegradable polymers, such as polylactic acid, may be used to replace some polyethylene packaging, little is known about their effects on marine organisms. Blue mussels, Mytilus edulis, have become a “model organism” for investigating the effects of microplastics in marine ecosystems. We show here that repeated exposure, over a period of 52 days in an outdoor mesocosm setting, of M. edulis to polyethylene microplastics reduced the number of byssal threads produced and the attachment strength (tenacity) by ~50%. Exposure to either type of microplastic altered the haemolymph proteome and, although a conserved response to microplastic exposure was observed, overall polyethylene resulted in more changes to protein abundances than polylactic acid. Many of the proteins affected are involved in vital biological processes, such as immune- and stress- regulation, metabolism and cellular and structural development. Our study highlights the utility of mass spectrometry-based proteomics to assess the health of key marine organisms and identifies the potential mechanisms by which microplastics, both conventional and biodegradable, could affect their ability to form and maintain reefs.
Project description:Abstract: Nanoparticles (NPs) are expected to make their way into the aquatic environment where sedimentation of particles will likely occur, putting benthic organisms at particular risk. Therefore, organisms such as Hyalella azteca, an epibenthic crustacean which forages at the sediment surface, is likely to have a high potential exposure. Here we show that Zinc Oxide (ZnO) NPs are more toxic to H. azteca compared with the corresponding metal ion, Zn2+. Dissolution of ZnO NPs contributes about 50% of the Zn measured in the ZnO NP suspensions, and cannot account for the toxicity of these particles to H. azteca. However, gene expression analysis is unable to distinguish between the ZnO NP exposures and Zinc Sulfate (ZnSO4) exposures at equitoxic concentrations. These results lead us to hypothesize that ZnO NPs provide and an enhanced exposure route for Zn2+ uptake into H. azteca, and possibly other sediment dwelling organisms. Our study supports the prediction that sediment dwelling organisms are highly susceptible to the effects of ZnO NPs and should be considered in the risk assessment of these nanomaterials. This experiment included four different treatments and an untreated control. Each treatment or control, consisted of ten independent replicates of twenty Hyalella azteca. Of these, six were randomly chosen to be used for the microarray analysis.