The environmental contamination by microplastics is a global challenge to ecosystem and human health, and the knowledge on the long-term effects of such particles is limited. Thus, the effects of ...microplastics and post-exposure recovery were investigated over 4 generations (F0, F1, F2, F3) using Daphnia magna as model. Effect criteria were parental mortality, growth, several reproductive parameters, and population growth rate. Microplastics exposure (0.1mg/l of pristine polymer microspheres 1–5μm diameter) caused parental mortality (10–100%), and significantly (p≤0.05) decreased growth, reproduction, and population growth rate leading to the extinction of the microplastics-exposed model population in the F1 generation. Females descending from those exposed to microplastics in F0 and exposed to clean medium presented some recovery but up to the F3 generation they still had significantly (p≤0.05) reduced growth, reproduction, and population growth rate. Overall, these results indicate that D. magna recovery from chronic exposure to microplastics may take several generations, and that the continuous exposure over generations to microplastics may cause population extinction. These findings have implications to aquatic ecosystem functioning and services, and raise concern on the long-term animal and human exposure to microplastics through diverse routes.
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•Transgerational effects and recovery from microplastics exposure were investigated in D. magna•Microplastics (0.1mg/l) decreased growth, reproduction and population growth rate•Microplastics caused the extinction of microplastics-exposed population in 2 generations•The recovery model population did not recover completely up to the F3 generation
As the accumulation of microplastics continues to rise in the marine environment, more knowledge on their potential toxic effects on marine organisms is needed to assess their risks to environmental ...and human health. Thus, the goal of the present study was to investigate the effects of fluorescent red polyethylene plastic micro-spheres 1–5 μm diameter (used as microplastic model and hereafter indicated as MP), alone and in mixture with copper, on the population growth of the marine microalgae Tetraselmis chuii. Two null hypotheses were tested: (H01) Exposure to MP concentrations in ppb range does not affect the average specific growth rate of T. chuii; (H02) MP do not interact with the toxicity of copper to T. chuii. In laboratory bioassays, T. chuii cultures were exposed for 96 h to MP concentrations ranging from 0.046 to 1.472 mg/l), concentrations of copper alone ranging from 0.02 to 0.64 mg/l, and the same concentrations of copper in the presence of 0.184 mg/l of MP in test media. No significant effects of MP on T. chuii population growth were found (p > 0.05), leading to the acceptance of H01. Copper alone significantly decreased the population growth of T. chuii with EC10, EC20 and EC50 of 0.009, 0.023 and 0.139 mg/l, respectively. The corresponding values in the presence of MP were 0.012, 0.029 and 0.145 mg/l, respectively. Moreover, the study found no significant differences between the toxicity curves of copper in the presence and absence of MP (p > 0.05), leading to the acceptance of H02. Despite these findings, because microplastics are known to adsorb and accumulate copper, aged pellets more than virgin ones, and the toxicity of smaller particles may be higher, further studies on the combined effects of copper and microplastics on microalgae should be performed, especially under long-term exposures to nano-sized aged microplastics.
•No significant effects of MP on the specific average of growth rate of T. chuii were found up to a concentration of 1.472 mg/l.•Significant differences between the toxicity curves of copper alone and when combined with microplastics were found.•MP decreased the copper-induced inhibition of T. chuii average growth rate.
The widespread use of microplastics and nanomaterials resulting in environmental contamination is of high concern. Microplastics have been found to modulate the toxicity of other environmental ...contaminants. Thus, the hypothesis that microplastics increase the toxicity of gold nanoparticles to the marine microalgae Tetraselmis chuii was tested. In a laboratory bioassay, T. chuii cultures were exposed for 96 h to ∼5 nm diameter gold nanoparticles (AuNP) and to virgin 1–5 μm diameter microplastics (MP), alone and in mixture. The treatments were: control; citrate-control; AuNP alone (0.1, 0.3 and 3 mg/L); MP alone (0.3, 0.9 and 4 mg/L) and mixture of the two substances in three different concentrations (0.1 mg/L AuNP + 0.3 mg/L MP; 0.3 mg/L AuNP + 0.9 mg/L MP; 3 mg/l AuNP + 4 mg/L MP). The effect criterion was the inhibition of the average specific growth rate. AuNP alone and MP alone did not cause significant decrease of T. chui average specific growth rate up to 3 mg/L and 4 mg/L, respectively. The mixture containing 3 mg/L AuNP + 4 mg/L MP significantly reduced the average specific growth rate of the microalgae. Therefore, this mixture was more toxic to T. chuii than its components individually. Overall, the results of the present study indicated that the MP and AuNP tested have a relatively low toxicity to T. chuii, but the toxicity increases when they are in mixtures containing high concentrations of both substances. These proof-of-concept findings stress the need of more research on the toxicity of mixtures containing microplastics and nanomaterials.
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•AuNP (≤3 mg/L) did not reduce significantly T. chuii specific growth rate.•Microplastics (MP) did not reduce significantly T. chuii growth rate up to 4 mg/L.•A AuNP-MP mixture significantly decreased T. chuii growth rate.
The effects of emerging environmental contaminants on human and environmental health is of high concern, especially those potentially induced by mixtures. The main goal of the present study was to ...assess the chronic effects of mixtures of citrate stabilized ≈5 nm gold nanoparticles (AuNP) and 1–5μm microplastics (MP) on Daphnia magna. A 21-day bioassay was carried out. The effect criteria were parental mortality, somatic growth and several reproductive parameters. AuNP induced parental mortality, reduced the total offspring and caused immobile juveniles and aborted eggs. MP induced parental mortality, delayed the first brood release, decreased the number of broods released, the total offspring, and caused immobile juveniles. All the mixtures caused higher toxicity than AuNP and MP alone. Based on parental mortality, evidences of antagonism between AuNP and MP were observed at low concentrations of both mixture components, whereas evidences of synergism at high concentrations were found. Chronic (21-day) exposure of D. magna to AuNPs, MP, and their mixtures can impair development, reproduction, ultimately leading to death.
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•21-day D. magna exposure to 5nm AuNP caused mortality and reproduction impairment.•21-day D. magna exposure to 1–5μm MP caused mortality and reproduction impairment.•Mixtures of AuNP and MP caused higher effects than the components individually.•Based on mortality, synergism at high concentrations of mixture components was found.•Based on mortality, antagonism at low concentrations of mixture components was found.
•Cefalexin inhibits Pomatoschistus microps predatory performance (96h-EC50=8mg/l).•Toxicological interactions between microplastics and cefalexin were found.•Temperature rise (20–25°C) increased ...cefalexin toxicity (96h-EC50=3.5mg/l).•Predatory performance inhibition may lead to population fitness decrease.
The goal of this study was to investigate the toxicity of cefalexin to Pomatoschistus microps juveniles in relation to the presence of microplastics in the water and temperature rise. After acclimatization, groups of wild juveniles were exposed for 96h to artificial salt water (control), microplastics alone (0.184mg/l), cefalexin alone (1.3–10mg/l) and in mixture with microplastics (cefalexin: 1.3–10mg/l; microplastics: 0.184mg/l) at 20 and 25°C. Effect criteria were mortality, post-exposure predatory performance (PEPP), acetylcholinesterase activity (AChE) and lipid peroxidation levels (LPO). At 20°C, concentrations of cefalexin alone≥5mg/l significantly reduced PEPP (up to 56%; 96h-EC50=8.4mg/l), indicating toxicity of the antibiotic to juveniles after short-term exposure to water concentrations in the low ppm range. At 20°C, fish exposed to microplastics alone did not have significant differences in any of the parameters tested relative to the control group but tended to have an inhibition of the PEPP (23%) and AChE (21%); at 25°C, microplastics alone caused mortality (33%) and PEPP inhibition (28%). Thus, microplastics are toxic to P. microps juveniles. At 20°C, under simultaneous exposure to cefalexin and microplastics, the PEPP was significantly reduced (at cefalexin concentrations≥1.25mg/l). Moreover, at 25°C, the toxicity curves of cefalexin (PEPP based), alone and in mixture with microplastics, were significantly different (p<0.05; 96h-EC50 of 3.8 and 5.2mg/l, respectively), and the integrated data analysis indicated significant interactions between the two substances for all biomarkers. Thus, the presence of microplastics in the water influenced the toxicity of cefalexin. The rise of water temperature (from 20°C to 25°C), increased the microplastics-induced mortality (from 8 to 33%), and the inhibitory effects of cefalexin on the PEPP (up to 70%). Significant differences (p<0.05) between the toxicity curves of cefalexin alone at distinct temperatures were found, with a lower 96h-EC50 at 25°C (3.8mg/l) than at 20°C (8.4mg/l). Moreover, at 25°C, increases of AChE activity (14%) and LPO (72%) in fish exposed to the mixture treatment containing the highest cefalexin concentration were found, and the integrated analysis of data indicated significant interactions between cefalexin and temperature for PEPP, and among all stressors for LPO. Thus, the temperature rise increased the toxicity of microplastics and of cefalexin, alone and in mixture with microplastics, to P. microps juveniles. These findings raise concern on the long-term exposure of wild populations to complex mixtures of pollutants, likely decreasing their fitness, and highlight the need of more research on the combined effects of widely used pharmaceuticals, microplastics and temperature increase on wild species to improve environmental and human risk assessments of chemicals and their safe use under a global warming scenario.
Recent studies have demonstrated the negative impacts of microplastics on wildlife. Therefore, the presence of microplastics in marine species for human consumption and the high intake of seafood ...(fish and shellfish) in some countries cause concern about the potential effects of microplastics on human health. In this brief review, the evidence of seafood contamination by microplastics is reviewed, and the potential consequences of the presence of microplastics in the marine environment for human food security, food safety and health are discussed. Furthermore, challenges and gaps in knowledge are identified. The knowledge on the adverse effects on human health due to the consumption of marine organisms containing microplastics is very limited, difficult to assess and still controversial. Thus, assessment of the risk posed to humans is challenging. Research is urgently needed, especially regarding the potential exposure and associated health risk to micro- and nano-sized plastics.
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•Marine microplastic debris may compromise human food security, food safety and health.•Microplastics have been detected in commercial sea food and other food items and drinking water.•Research on analytical methods, toxicity and toxicokinetics in humans of micro- and nano-sized plastics is needed.•Our knowledge in this field is still far from complete.
Microplastics (MPs) are plastic particles with less than 5 mm in size that are considered global environmental pollutants. The MPs present in the environment result from the successive breakdown of ...larger plastic pieces or from the direct input of micro- and nano-sized particles used in various industries and products available to consumers. Such MPs have been found in several wild species and other natural resources, including some consumed as food by humans, with possible adverse effects on ecosystem and human health. The central aim of this work was to review the published literature regarding the contamination of sea commercial salts (sea and terrestrial origins) and its possible impacts on human health. Moreover, to lead to a comprehensive understanding of the paradigm, a short introduction and revision of the environmental contamination by MPs and its effects are included. MPs have been found in commercial salts from 128 brands, from 38 different countries spanning over five continents. The concentration of MPs found in the samples analysed is lower than the concentrations of MPs reported in other resources, such as blue mussels. However, as commercial salts are used every day and by all humans, they constitute a long-term exposure route for the general population in addition to others (e.g., animals consumed as food by humans, water, air). Therefore, commercial salts contaminated with MPs may contribute to the potential long-term adverse effects resulting from human exposure to these particles.
•Plastics as marine debris are the new addition to the list of global threats.•Marine pollution will undoubtedly lead to the contamination of sea products.•Microplastics in salts might pose a threat to human food safety and health.•Microplastics sorb contaminants and transfer them to salt and other products.
The presence of microplastics and several other pollutants in the marine environment is of growing concern. However, the knowledge on the toxicity of mixtures containing microplastics and other ...contaminants to marine species is still scarce. The main goals of this study were to investigate the oxidative stress and lipid oxidative damage potentially induced by 96 h of exposure to mercury (0.010 and 0.016 mg/L), microplastics (0.26 and 0.69 mg/L), and mixtures of the two substances (same concentrations, full factorial) in the gills and liver of D. labrax juveniles, and the possible influence of microplastics on mercury bioconcentration (gills) and bioaccumulation (liver). The results indicate that the presence of microplastics in the water increased the concentration of mercury in gills and liver of D. labrax juveniles. Microplastics and mercury, alone and in mixtures, caused oxidative stress in both organs. Based on the total induction of antioxidant enzymatic activity, the type of toxicological interaction in fish exposed to the mixture containing the lowest concentration of the two substances was addition in gills, and addition or synergism in the liver. These results stress the need to further address the role of microplastics in the bioconcentration, bioaccumulation, and toxicity of other environmental contaminants in different species.
Microplastics and mercury are environmental pollutants of great concern. The main goal of the present study was to investigate the effects of these pollutants, both individually and in binary ...mixtures, on the swimming performance of juvenile European seabass, Dicentrarchus labrax. Microplastics alone, mercury alone and all the mixtures caused significant reduction of the swimming velocity and resistance time of fish. Moreover, changes in behavioural responses including lethargic and erratic swimming behaviour were observed. These results highlight that fish behavioural responses can be used as sensitive endpoint to establish the effects of contamination by microplastics and also emphasizes the need to assess the combined effects of microplastics and other environmental contaminants, with special attention to the effects on behavioural responses in fish and other aquatic species.
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•Microplastics (MPs) and mercury had negative effects on swimming performance of Dicentrarchus labrax.•MPs per see may cause reduction of the swimming velocity and resistance time of fish when swimming against the water flow.•Fish behavioural responses can be use as a sensitive endpoints to establish effects from contamination by microplastics•These findings have implications to aquatic organisms.
•Fish exposed to Au-NP had gold in their body and a decreased predatory performance.•Thus, exposure to Au-NP may negatively affect the health and fitness of P. microps.•Temperature rise increased ...gold body burden and interacted with chemicals’ effects.•The presence of MP did not change the toxic effects of Au-NP to P. microps.
Knowledge on multi-stressors effects required for environmental and human risk assessments is still limited. This study investigated the combined effects of gold nanoparticles (Au-NP), microplastics (MP) and temperature increase on Pomatoschistus microps, an important prey for several higher level predators, including some species edible to humans. Four null hypotheses were tested: H01: P. microps juveniles do not take up Au-NP through the water; H02: Au-NP (ppb range) are not toxic to juveniles; H03: the presence of MP do not influence the effects of Au-NP on juveniles; H04: temperature increase (20–25°C) does not change the effects of the tested chemicals on juveniles. Wild juveniles were acclimated to laboratory conditions. Then, they were exposed to Au-NP (≈5nm diameter) and MP (polyethylene spheres, 1–5μm diameter), alone and in mixture, at 20°C and 25°C, in semi-static conditions. After 96h of exposure to Au-NP, fish had gold in their body (0.129–0.546μg/g w.w.) leading to H01 refusal. Exposure to Au-NP alone caused a predatory performance decrease (≈−39%, p<0.05) leading to H02 refusal. MP did not change the Au-NP toxicity leading to H03 acceptance. Temperature rise significantly increased the concentration of gold in fish exposed to Au-NP (≈2.3 fold), and interacted with chemical effects (e.g. glutathione S-transferases activity) leading to H04 refusal. Thus, the results of this study highlight the importance of further investigating the effects of multi-stressors on marine fish, particularly the effects of temperature on the uptake, biotransformation, elimination and effects of nanoparticles and microplastics, either alone or in mixture. This knowledge is most important to improve the basis for environmental and human risk assessments of these environmental contaminants of high concern.
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