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Musters, C.J.M.; Hunting, E.R.; Schrama, M.J.J.; Cieraad, E.; Barmentlo, S.H.; Ieromina, O.; ... ; Bodegom, P.M. van 2019

Spatial and temporal homogenisation of freshwater macrofaunal communities in ditches

Article / Letter to editor

open access

There is a widespread concern that we are witnessing an ongoing homogenisation of ecological communities. However, in contrast to human impacts on spatial patterns in biodiversity, human impacts on...

There is a widespread concern that we are witnessing an ongoing homogenisation of ecological communities. However, in contrast to human impacts on spatial patterns in biodiversity, human impacts on the temporal aspects of β‐diversity have received little attention. Moreover, the interplay between spatial and temporal β‐diversity is poorly understood. To address this knowledge gap, we assessed dissimilarity within freshwater macrofaunal communities of drainage ditches to determine spatiotemporal β‐diversity as well as homogenisation in relation to different types of land use.
We considered four distinct changes in community composition: spatial turnover, temporal turnover, spatial variation over time, and temporal variation in space, as well as the combined effects of space and time on β‐diversity. As a metric of dissimilarity, we calculated the taxonomic Hellinger distance between samples from different locations and time points and correlated these with distance in space and in time, as well as with three spatial variables, including land‐use type, and two temporal variables. We studied the effect of interactions between spatial and temporal variables on dissimilarity by applying a permutational analysis of variance.
Our results illustrate the importance of changes in community composition in time with respect to temporal turnover, spatial variation over time, and temporal variation in space. While we did not find spatial turnover in community composition, both month and year had a considerable effect. Within a year, β‐diversity decreased over the months, yet these assembly patterns differed between years. This suggests major effects of seasonal and year‐to‐year dynamics on β‐diversity. Land use was also observed to be a main driver: ditches in nature conservation areas had higher β‐diversity and temporal heterogeneity was lowest in ditches adjacent to the most intensive agricultural land‐use category, indicating that agricultural practices can homogenise biodiversity in both space and time.
By analysing the spatial and temporal β‐diversity patterns in freshwater macrofaunal communities in concert, we have shown that β‐diversity is a sensitive and highly informative metric of both spatial and temporal changes in community composition.

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Zhai, Y.; Hunting, E.R.; Liu, G.; Baas, E.; Peijnenburg, W.J.G.M.; Vijver, M.G. 2019

Compositional alterations in soil bacterial communities exposed to TiO2 nanoparticles are not reflected in functional impacts

Article / Letter to editor

open access

Wassenaar, P.N.H.; Verbruggen, E.M.J.; Cieraad, E.; Peijnenburg, W.J.G.M.; Vijver, M.G. 2019

Variability in fish bioconcentration factors: Influences of study design and consequences for regulation

Article / Letter to editor

open access

The fish bioconcentration factor (BCF) is an important aspect within bioaccumulation assessments. Several factors have been suggested to influence BCF values – including species, developmental... Show moreThe fish bioconcentration factor (BCF) is an important aspect within bioaccumulation assessments. Several factors have been suggested to influence BCF values – including species, developmental stage, mixture exposure, and calculation method. However, their exact contribution to variance in BCF values is unknown. Within this study we assessed the relative impact of these test characteristics on BCF values and analyzed the reproducibility of aquatic exposure bioconcentration tests.Linear mixed effects analyses were performed on a newly develop database to investigate the relationship between the response variable (i.e. lipid normalized log BCF values) and several test characteristics as fixed effects.Lower BCF values were observed for substances that were simultaneously applied with high molecular weight polycyclic aromatic hydrocarbons compared to single substance exposure (with an average difference of −0.81 log BCF). Also, lower BCFs upon kinetic determination were observed compared to steady-state BCFs (log BCF -0.27), and lower BCFs for species from the Ostariophysi subcohort level (log BCF -0.17 to −0.15). In addition, data analysis showed high variation within BCF values for single substances (average SD = log BCF 0.21), which questions the robustness of the current bioaccumulation assessments. For example, the 95% confidence range of a BCF value of 2500 ranges from 953 (‘not-bioaccumulative’) to 6561 (‘very bioaccumulative’).Our results show that the use of one single BCF leads to a high uncertainty in bioaccumulation assessments. We strongly recommend that within future bioconcentration studies, the used experimental design and test conditions are described in detail and justified to support solid interpretation. Show less

Barmentlo, S.H.; Schrama, M.J.J.; Bodegom, P.M. van; Snoo, G.R. de; Musters, C.J.M.; Vijver, M.G. 2019

Neonicotinoids and fertilizers jointly structure naturally assembled freshwater macroinvertebrate communities

Article / Letter to editor

open access

Although it is widely acknowledged that a decline of freshwater biodiversity jeopardizes the functioning of freshwater ecosystems, the large number of (human-induced) pressures jointly acting on... Show moreAlthough it is widely acknowledged that a decline of freshwater biodiversity jeopardizes the functioning of freshwater ecosystems, the large number of (human-induced) pressures jointly acting on these systems hampers managing its biodiversity. To disentangle the magnitude and the temporal effects of these single and interacting pressures, experiments are required that study how these pressures affect the structuring of natural communities. We performed experiments with naturally assembled invertebrate communities in 36 experimental ditches to assess the single and joint effects of environmentally relevant concentrations of two commonly co-occurring stressors: fertilizer inputs and neonicotinoid insecticides, in this case thiacloprid. Specifically, we explored whether these agrochemicals result in sustained changes in community structure by inspecting divergence, convergence and short- /long-lived dissimilarity of communities, when compared to a control treatment. Our results indicate strong impacts on the abundance of different taxa by exposure to the agrochemicals. However, we found no effect of any treatment on total abundance, taxon richness or convergence/divergence (measured as beta dispersion) of the communities. Moreover, we found contrasting responses when both joint stressors were present: when considering abundance of different taxa, we observed that fertilizer additions reduced some of the thiacloprid toxicity. But when assessing the community structure, we found that exposure to both stressors consistently resulted in a more dissimilar community compared to the control. This dissimilarity was persistent up to four months after applying the agrochemicals, even though there was a turnover in taxa explaining this dissimilarity. This turnover indicates that the persistent dissimilarity can potentially be attributed to a rippling effect in the community rather than continued toxicity. Such shifts in natural freshwater invertebrate communities, months after the actual exposure, suggests that stressors may have important long-term repercussions for which may subsequently lead to changes in ecosystem functioning. Show less

Barmentlo, S.H.; Vriend, L.M.; Grunsven, R.H.A. van; Vijver, M.G. 2019

Environmental levels of neonicotinoids reduce prey consumption, mobility and emergence of the damselfly Ischnura elegans

Article / Letter to editor

open access

Arenas Lago, D.; Abdolahpur Monikh, F.; Vijver, M.G.; Peijnenburg, W.J.G.M. 2019

Interaction of zero valent copper nanoparticles with algal cells under simulated natural conditions: Particle dissolution kinetics, uptake and heteroaggregation

Article / Letter to editor

open access

Some metal-based engineered nanoparticles (ENPs) undergo fast dissolution and/or aggregation when they are released in the environment. The underlying processes are controlled by psychochemical... Show moreSome metal-based engineered nanoparticles (ENPs) undergo fast dissolution and/or aggregation when they are released in the environment. The underlying processes are controlled by psychochemical/biological parameters of the environment and the properties of the particles. In this study, we investigated the interaction between algal cells and zero valent copper nanoparticles (Cu0-ENPs) to elucidate how the cells influence the dissolution and aggregation kinetics of the particles and how these kinetics influence the cellular uptake of Cu. Our finding showed that the concentration of dissolved Cu ([Cu]dissolved) in the supernatant of the culture media without algal cells was higher than the [Cu]dissolved in the media with algal cells. In the absence of the cells, dissolved organic matter (DOC) increased the dissolution of the particle due to increasing the stability of the particles against aggregation, thus increasing the available surface area. In the presence of algae, Cu0-ENPs heteroaggregated with the cells. Thus, the available surface area decreased over time and this resulted in a low dissolution rate of the particles. The DOC corona on the surface of the particles increased the heteroaggregation of the particles with the cells and decreases the uptake of the particles. Our findings showed that microorganisms influence the fate of ENPs in the environment, and they do so by modifying the dissolution and aggregation kinetics of the Cu0-ENPs. Show less

Vijver, M.G. 2019

Virus brengt pesticide in bodem

Event

open access

Bosker, T.; Olthof, G.; Vijver, M.G.; Baas, J.; Barmentlo, S.H. 2019

Significant decline of Daphnia magna population biomass due to microplastic exposure

Article / Letter to editor

open access

Even though microplastics are intensively studied, the focus of the research is mainly on relatively short term effects at high doses. Therefore there is a need to shift the focus toward more... Show moreEven though microplastics are intensively studied, the focus of the research is mainly on relatively short term effects at high doses. Therefore there is a need to shift the focus toward more realistic, longer-term endpoints. Studies with a range of chemicals have shown that the response of populations often differs from studies in which a single organism is exposed in an individual container (as often described within standard ecotox screening assays). Here we investigate the impact of primary microplastics (1–5 μm in size) on a population of Daphnia magna. We first allowed a stable population of D. magna to develop over 29 d, after which the populations were exposed to microplastics for three weeks (concentrations ranging from 102 to 105 particles mL−1 and a control). We found a significant impact of microplastics on the total population of D. magna, with a reduction in the amount of adult daphnids. Importantly, when expressed as total biomass, exposure to 105 microplastics mL−1 resulted in a 21% reduction in total biomass compared to control. These results indicate that exposure to microplastics can result in significant adverse effects on the population of D. magna, including a reduction in the number of individuals as well as total biomass. Given the importance of D. magna in freshwater food webs, both as a grazer as well as a food source, this can potentially impact the functioning of the ecosystem. Show less

Vijver, M.G. 2019

The choreography of chemicals in nature; beyond ecotoxicological limits

Article / Letter to editor

open access

Arenas Lago, D.; Abdolahpur Monikh, F.; Vijver, M.G.; Peijnenburg, W.J.G.M. 2019

Dissolution and aggregation kinetics of zero valent copper nanoparticles in (simulated) natural surface waters: Simultaneous effects of pH, NOM and ionic strength

Article / Letter to editor

open access

The combined effects of pH, dissolved organic carbon (DOC) and Ca2+/Mg2+ on the dissolution and aggregation kinetics of zero valent copper engineered nanoparticles (Cu0 ENPs) were investigated. The... Show moreThe combined effects of pH, dissolved organic carbon (DOC) and Ca2+/Mg2+ on the dissolution and aggregation kinetics of zero valent copper engineered nanoparticles (Cu0 ENPs) were investigated. The dissolution and aggregation of the particles were studied in (a) synthetic aqueous media, similar in chemistry to natural surface waters, and (b) natural surface waters samples, for up to 32 or 24 h. The DOC stabilized the particles and prevented aggregation, and thus increased the available surface area. The higher available surface area in turn accelerated the dissolution of the particles. The presence of Ca2+/Mg2+, however, changed the aggregation and the dissolution of the DOC-stabilized particles. The influence of Ca2+/Mg2+ on DOC-stabilized particles was different at different pH's. In the absence of DOC, 10 mM of Ca2+/Mg2+ induced charge reversal on the particles and caused particle stability against aggregation. This subsequently increased particles dissolution. The results obtained with regard to dissolution and aggregation of the particles in natural surface waters were compared with those determined for the synthetic waters. This comparison showed that the behavior of the particles in the natural surface waters was mostly similar to the behavior determined for media at pH 9. Overall, the current study provides some novel insights into the simultaneous effects of physicochemical parameters of water on particle stability against aggregation and dissolution, and provides data about how the processes of aggregation and dissolution of Cu0 ENPs interact and jointly determine the overall particle fate. Show less

Pallas, G.; Vijver, M.G.; Peijnenburg, W.J.G.M.; Guinee, J.B. 2019

Life cycle assessment of emerging technologies at the lab scale: The case of nanowire-based solar cells

Article / Letter to editor

open access

Nanomaterials are expected to play an important role in the development of sustainable products. The use of nanomaterials in solar cells has the potential to increase their conversion efficiency.... Show moreNanomaterials are expected to play an important role in the development of sustainable products. The use of nanomaterials in solar cells has the potential to increase their conversion efficiency. In this study, we performed a life cycle assessment (LCA) for an emerging nanowire‐based solar technology. Two lab‐scale manufacturing routes for the production of nanowire‐based solar cells have been compared—the direct growth of GaInP nanowires on silicon substrate and the growth of InP nanowires on native substrate, peel off, and transfer to silicon substrate. The analysis revealed critical raw materials and processes of the current lab‐scale manufacturing routes such as the use of trifluoromethane (CHF3), gold, and an InP wafer and a stamp, which are used and discarded. The environmental performance of the two production routes under different scenarios has been assessed. The scenarios include the use of an alternative process to reduce the gold requirements—electroplating instead of metallization, recovery of gold, and reuse of the InP wafer and the stamp. A number of suggestions, based on the LCA results—including minimization of the use of gold and further exploration for upscaling of the electroplating process, the increase in the lifetimes of the wafer and the stamp, and the use of fluorine‐free etching materials—have been communicated to the researchers in order to improve the environmental performance of the technology. Finally, the usefulness and limitations of lab‐scale LCA as a tool to guide the sustainable development of emerging technologies are discussed. Show less

Bosker, T.; Bouwman, L.J.; Brun, N.R.; Behrens, P.; Vijver, M.G. 2019

Microplastics accumulate on pores in seed capsule and delay germination and root growth of the terrestrial vascular plant Lepidium sativum

Article / Letter to editor

open access

Jaikumar, G.; Brun, N.R.; Vijver, M.G.; Bosker, T. 2019

Reproductive toxicity of primary and secondary microplastics to three cladocerans during chronic exposure

Article / Letter to editor

open access

Microplastics (<5 mm) are distributed ubiquitously in natural environments. The majority of microplastics in aquatic environments are shown to have rough surfaces due to various weathering... Show moreMicroplastics (<5 mm) are distributed ubiquitously in natural environments. The majority of microplastics in aquatic environments are shown to have rough surfaces due to various weathering processes (secondary microplastics; SMP), while laboratory studies predominantly utilise pristine microplastics (primary microplastics; PMP). Here we present the results from a study comparing the chronic effects of pristine PMP and artificially weathered SMP to three different Cladoceran species (Daphnia magna, Daphnia pulex, Ceriodaphnia dubia). We assessed the impact of PMP and SMP on reproductive output using various measured parameters, including time of first brood, size of first brood, size of first three broods, cumulative number of neonates, total number of broods and terminal length of test animals. Our results show that reproductive output of all species declined in a dose-dependent manner. The No Observed Effect Concentration (NOEC) was less than the lowest tested concentration (102 p/mL) for at least one measured endpoint for all species and both PMP and SMP. Further, it was inferred that species sensitivity varied inversely with body size for most endpoints, resulting in C. dubia being the most sensitive species; and D. magna being the least sensitive species under study. In addition, PMP appeared to have greater toxic potential as compared to SMP. This study is the first to directly compare the chronic toxicity of both pristine and weathered microplastic particles on three freshwater toxicological model organisms. Our results indicate that sensitivity in reproduction and growth to microplastics may differ between species and type of microplastic exposed; highlighting the importance of using multiple species and structural types of particles. Show less

Ohajinwa, C.M.; Bodegom, P.M. van; Osibanjo, O.; Xie, Q.; Chen, .J.; Vijver, M.G.; Peijnenburg, W.J.G.M. 2019

Health Risks of Polybrominated Diphenyl Ethers (PBDEs) and Metals at Informal Electronic Waste Recycling Sites

Article / Letter to editor

open access

-waste workers cannot be over emphasised.

Ohajinwa, C.; Bodegom, P. van; Xie, Q.; Chen, J.; Vijver, M.G.; Osibanjo, O.; Peijnenburg, W.J.G.M. 2019

Hydrophobic Organic Pollutants in Soils and Dusts at Electronic Waste Recycling Sites: Occurrence and Possible Impacts of Polybrominated Diphenyl Ethers

Article / Letter to editor

open access

Doak, S.; Vijver, M.G.; Clift, M. 2019

Nanomaterialen veranderen de wereld, maar wat doen ze met onze gezondheid?

Event

open access

Abdolahpur Monikh, F.; Chupani, L.; Vijver, M.G.; Vancová, M.; Peijnenburg, W.J.G.M. 2019

Analytical approaches for characterizing and quantifying engineered nanoparticles in biological matrices from an (eco)toxicological perspective: old challenges, new methods and techniques

Article / Letter to editor

open access

To promote the safer by design strategy and assess environmental risks of engineered nanoparticles (ENPs), it is essential to understand the fate of ENPs within organisms. This understanding in... Show moreTo promote the safer by design strategy and assess environmental risks of engineered nanoparticles (ENPs), it is essential to understand the fate of ENPs within organisms. This understanding in living organisms is limited by challenges in characterizing and quantifying ENPs in biological media. Relevant literature in this area is scattered across research from the past decade or so, and it consists mostly of medically oriented studies. This review first introduces those modern techniques and methods that can be used to extract, characterize, and quantify ENPs in biological matrices for (eco)toxicological purposes. It then summarizes recent research developments within those areas most relevant to the context and field that are the subject of this review paper. These comprise numerous in-situ techniques and some ex-situ techniques. The former group includes techniques allowing to observe specimens in their natural hydrated state (e.g., scanning electron microscopy working in cryo mode and high-pressure freezing) and microscopy equipped with elemental microanalysis (e.g., energy-dispersive X-ray spectroscopy); two-photon laser and coherent anti-Stokes Raman scattering microscopy; absorption-edge synchrotron X-ray computed microtomography; and laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS). The latter group includes asymmetric flow field flow fractionation coupled with ICP-MS and single particle-ICP-MS. Our review found that most of the evidence gathered for ENPs actually focused on a few metal-based ENPs and carbon nanotube and points to total mass concentration but no other particles properties, such as size and number. Based on the obtained knowledge, we developed and presented a decision scheme and analytical toolbox to help orient scientists toward selecting appropriate ways for investigating the (eco)toxicity of ENPs that are consistent with their properties. Show less

Verschoor, A.J.; Harper, S.; Delmaar, C.J.E.; Park, M.V.D.Z.; Sips, A.J.A.M.; Vijver, M.G.; Peijnenburg, W.J.G.M. 2019

Systematic selection of a dose metric for metal-based nanoparticles

Article / Letter to editor

open access

Mass is traditionally the unique measure of the administered dose in toxicity studies with conventional chemical substances. Because of the variety of specific physical properties of nanoparticles,... Show moreMass is traditionally the unique measure of the administered dose in toxicity studies with conventional chemical substances. Because of the variety of specific physical properties of nanoparticles, other dose metrics such as the number of particles, their size, shape, surface area or volume may be more appropriate. Here we applied a systematic, unbiased approach to derive the most appropriate dose metric for nanoparticles from experimental data. The approach was exemplified for copper, zinc oxide, and silver nanoparticles with different diameters, coatings and shapes, combining experiments with six aquatic organisms, two mammalian and two piscine liver cell lines from different research groups. The nanoparticle diameter appeared to be a powerful estimator of metal oxide nanoparticle effects. Since effect concentrations were related to size to the power 3, it is indicated that volume (mass) is the appropriate dose metric for all tested species and toxicological endpoints and all tested metal oxide nanoparticles within the tested size range (25–500 nm). The new method enables extrapolation of test results from one type of metal oxide nanomaterial to another, thereby offering a powerful tool to improved efficiency in risk research and risk assessment of nanomaterials. Show less

Barmentlo, S.H.; Schrama, M.J.J.; Bodegom, P.M. van; Snoo, G.R. de; Musters, C.J.M.; Vijver, M.G. 2019

Neonicotinoids and fertilizers jointly structure naturally assembled freshwater macroinvertebrate communities

Article / Letter to editor

open access

Brun, N.R.; Hage, P. van; Hunting, E.R.; Haramis, A.-P.G.; Vink, S.C.; Vijver, M.G.; ... ; Tudorache, C. 2019

Polystyrene nanoplastics disrupt glucose metabolism and cortisol levels with a possible link to behavioural changes in larval zebrafish

Article / Letter to editor

open access

Plastic nanoparticles originating from weathering plastic waste are emerging contaminants in aquatic environments, with unknown modes of action in aquatic organisms. Recent studies suggest that... Show morePlastic nanoparticles originating from weathering plastic waste are emerging contaminants in aquatic environments, with unknown modes of action in aquatic organisms. Recent studies suggest that internalised nanoplastics may disrupt processes related to energy metabolism. Such disruption can be crucial for organisms during development and may ultimately lead to changes in behaviour. Here, we investigated the link between polystyrene nanoplastic (PSNP)-induced signalling events and behavioural changes. Larval zebrafish exhibited PSNP accumulation in the pancreas, which coincided with a decreased glucose level. By using hyperglycemic and glucocorticoid receptor (Gr) mutant larvae, we demonstrate that the PSNP-induced disruption in glucose homoeostasis coincided with increased cortisol secretion and hyperactivity in challenge phases. Our work sheds new light on a potential mechanism underlying nanoplastics toxicity in fish, suggesting that the adverse effect of PSNPs are at least in part mediated by Gr activation in response to disrupted glucose homeostasis, ultimately leading to aberrant locomotor activity. Show less

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