The Toxicity of Coated Silver Nanoparticles and Their Stabilizers towards Paracentrotus lividus Sea Urchin Embryos

Surface modification of nanoparticles with different stabilizers is one of the most widely used methods to improve their stability and applicability. Silver nanoparticle (AgNPs) dispersions with biologically active stabilizers have great potential as plant protection products with synergetic antimicrobial properties and sufficient stability in terms of field application. The obtained AgNPs dispersions have the ability to enhance growth, increase yield and give better protection to various crops. At the same time, it is important to determine the fate, stability, and ecotoxicity of the applied nanosized products. The toxic effects of AgNPs dispersions and their constituents, organic stabilizers and additives, were evaluated using a phenotypic sea urchin embryo assay. Certain AgNPs dispersions with organic stabilizers demonstrated sufficient stability, even in seawater. The toxicity of the AgNPs decreased with the increasing tendency to agglomerate in seawater. Furthermore, the applied stabilizers were hazardous towards sea urchin embryos. They caused pronounced embryo abnormalities at 0.25-2.6 mg/L concentrations. AgNPs exhibited a lethal effect at concentrations that were equal to the MLC or exceeded the MEC of their stabilizers. Silver ions were more toxic towards sea urchin embryos than AgNPs.

Short-Term Exposure to Nanoplastics Does Not Affect Bisphenol A Embryotoxicity to Marine Ascidian Ciona robusta

Plastic pollution is recognized as a global environmental threat and concern is increasing regarding the potential interactions of the smallest fragments, nanoplastics (1 µm), with either physical and chemical entities encountered in the natural environment, including toxic pollutants. The smallest size of nanoplastics (<100nm) rebounds to their safety associated with remarkable biological, chemical and physical reactivity that allow them to interact with cellular machinery by crossing biological barriers and causing damage to living beings. Recent findings on nanoplastic occurrence in marine coastal waters, including the Mediterranean Sea, leave open the question on their ability to act as a vector of other contaminants of emerging concerns (CECs) concomitantly released by wastewater treatment plants and reaching marine coastal waters. Here, we assess for the first time the role of non-functionalized polystyrene nanoparticles (PS NPs, 20 nm) as a proxy for nanoplastics (1 and 10 µg/mL) alone and in combination with bisphenol A (BPA) (4.5 and 10 µM) on Ciona robusta embryos (22 h post fertilization, hpf) by looking at embryotoxicity through phenotypic alterations. We confirmed the ability of BPA to impact ascidian C. robusta embryo development, by affecting sensory organs pigmentation, either alone and in combination with PS NPs. Our findings suggest that no interactions are taking place between PS NPs and BPA in filtered sea water (FSW) probably due to the high ionic strength of seawater able to trigger the sorption surface properties of PS NPs. Further studies are needed to elucidate such peculiarities and define the risk posed by combined exposure to BPA and PS NPs in marine coastal waters.

Influence of pH on the Kinetics and Products of Photocatalytic Degradation of Sulfonamides in Aqueous Solutions

The aims of the study were to determine the kinetics of the photocatalytic degradation of six sulfonamides in the presence of TiO₂-P25 in acidic, neutral, and alkaline solutions and to identify the structures of the stable products. It was stated that the pH of the solution significantly affected the photocatalytic degradation rate of sulfonamides in acidic and alkaline environments, and the effect likely depended on the susceptibility of sulfonamides to attack by hydroxyl radicals. In the post-reaction mixture, we identified the compounds resulting from the substitution of the aromatic rings with a hydroxyl group; the amide hydrolysis products; the hydroxylamine-, azo, and nitro derivatives; and the compounds formed via the elimination of the sulfone group. Moreover, previously unknown azo compounds were detected. Some degradation products of sulfonamides may exhibit marked bacteriostatic activity and high phytotoxicity. The azo and nitro compounds formed in an acidic environment may be potentially more toxic to aquatic ecosystems than the initial compounds.

Assessment of the Chronic Toxicity and Interactions between Arsenic and Riverbed Biofilms

The toxic effect of exposure to arsenic, As(V), at concentrations of 0 to 30 mg L^-1, for 49 days, on epipsammic biofilms, was evaluated in a microcosm experiment. The growth and composition of biofilms developed on sediments containing As concentrations of 31 mg kg^-1 and 85 mg kg^-1 were compared, using photosynthetic parameters and Live/Dead stains as end points. A toxic effect of arsenic could not be demonstrated; however, biofilm growth was higher over the sediment with higher arsenic concentrations, suggesting the development of pollution-induced community induced tolerance (PICT). Nevertheless, PICT was not observed after exposure to high arsenic concentration in the laboratory, as there were no differences in algal growth between the previous 0 and 30 mg L^-1 systems exposed to new 30 mg As L^-1 dissolution over 29 days. The algal composition was affected by the added arsenic, and brown algae were the most tolerant compared to green algae and cyanophyceae, as their percentage increased from 25 and 33% in the control samples to 57 and 47% in the samples with the highest added As concentration. In turn, the biofilm development influenced arsenic redistribution and speciation. Arsenic concentration in water decreased with time during the incubation experiment, retained by the sediment particles and the biofilm. In the biofilm, extracellular As was significantly higher (up to 11 times) than intracellular arsenic. As(V) was the predominant species in water and in the biofilm, but products of biotic transformation, namely As(III), DMA(V) and MMA(V), were also found in the solution and in the biofilm in some systems, demonstrating reduction and methylation by the organisms. As a conclusion, a toxic effect was not detected for the concentrations evaluated. Biofilms naturally exposed in the river system to high As concentrations acquire pollution-induced tolerance; however, tolerance was not acquired by exposure to 30 mg L^-1 for 29 days in the laboratory.

Assessment of the Effects of Triticonazole on Soil and Human Health

Triticonazole is a fungicide used to control diseases in numerous plants. The commercial product is a racemate containing (R)- and (S)-triticonazole and its residues have been found in vegetables, fruits, and drinking water. This study considered the effects of triticonazole on soil microorganisms and enzymes and human health by taking into account the enantiomeric structure when applicable. An experimental method was applied for assessing the effects of triticonazole on soil microorganisms and enzymes, and the effects of the stereoisomers on soil enzymes and human health were assessed using a computational approach. There were decreases in dehydrogenase and phosphatase activities and an increase in urease activity when barley and wheat seeds treated with various doses of triticonazole were sown in chernozem soil. At least 21 days were necessary for the enzymes to recover the activities. This was consistent with the diminution of the total number of soil microorganisms in the 14 days after sowing. Both stereoisomers were able to bind to human plasma proteins and were potentially inhibitors of human cytochromes, revealing cardiotoxicity and low endocrine disruption potential. As distinct effects, (R)-TTZ caused skin sensitization, carcinogenicity, and respiratory toxicity. There were no significant differences in the interaction energies of the stereoisomers and soil enzymes, but (S)-TTZ exposed higher interaction energies with plasma proteins and human cytochromes.

Self-Assembled Nanoparticles of a Prodrug Conjugate Based on Pyrimethanil for Efficient Plant Disease Management

Self-assembled nanotechnology is a promising strategy for improving the effective utilization of pesticides due to its distinct advantages. Herein, an amide-bonded prodrug conjugate based on pyrimethanil (PYR) and butyric acid (BA) was successfully synthesized by the nucleophilic substitution reaction and subsequently self-assembled into spherical nanoparticles (PB NPs) with an average size of 85 nm through the solvent exchange method without using any toxic adjuvant. The results showed that PB NPs based on PYR and BA had a synergistic antimicrobial activity against S. sclerotiorum on plant leaves due to good photostability, low volatilization, good surface activity, and improved retention. Additionally, PB NPs could be used by plant cells as nutrients to promote the growth of plants and thus reduced the toxicity of PYR to plant. Therefore, this prodrug conjugate self-assembly nanotechnology would provide a promising strategy for improving the effective utilization rates of pesticides and reducing their toxicities to plants.

Towards Sustainable Wastewater Treatment: Bioindication as a Technique for Supporting Treatment Efficiency Assessment

Constructed wetlands (CWs) are a promising alternative for conventional methods of wastewater treatment. However, the biggest challenge in wastewater treatment is the improvement of the technology used so that it is possible to remove micropollutants without additional costs. The impact of wastewater treatment in CWs on toxicity towards Aliivibrio fischeri, Daphnia magna and Lemna minor was investigated. The effects of feeding regime (wastewater fed in five batches per week at a batch volume of 1 L, or twice per week at a batch volume of 2.5 L) and the presence of pharmaceuticals (diclofenac and sulfamethoxazole), as well as the presence of Miscantus giganteus plants in CW columns (twelve of the 24 columns that were planted) were analyzed. A reduction in toxicity was observed in all experimental setups. The effluents from constructed wetlands were classified as moderately toxic (average TU for A. fischeri, D. magna and L. minor was 0.9, 2.5 and 5.5, respectively). The feeding regime of 5 days of feeding/2 days of resting resulted in a positive impact on the ecotoxicological and chemical parameters of wastewater (removal of TOC, N-NH₄ and pharmaceuticals). Extended exposure of Miscantus giganteus to the wastewater containing pharmaceuticals resulted in elevated activity of antioxidant enzymes (catalase and superoxide dismutase) in leaf material.

Assessment of the Effects of Chitosan, Chitooligosaccharides and Their Derivatives on Lemna minor

Chitosan, chitooligosaccharides and their derivatives’ production and use in many fields may result in their release to the environment, possibly affecting aquatic organisms. Both an experimental and a computational approach were considered for evaluating the effects of these compounds on Lemna minor. Based on the determined EC50 values against L. minor, only D-glucosamine hydrochloride (EC50 = 11.55 mg/L) was considered as “slightly toxic” for aquatic environments, while all the other investigated compounds, having EC50 > 100 mg/L, were considered as “practically non-toxic”. The results obtained in the experimental approach were in good agreement with the predictions obtained using the admetSAR2.0 computational tool, revealing that the investigated compounds were not considered toxic for crustacean, fish and Tetrahymena pyriformis aquatic microorganisms. The ADMETLab2.0 computational tool predicted the values of IGC50 for Tetrahymena pyriformis and the LC50 for fathead minnow and Daphnia magna, with the lowest values of these parameters being revealed by totally acetylated chitooligosaccharides in correlation with their lowest solubility. The effects of the chitooligosaccharides and chitosan on L. minor decreased with increased molecular weight, increased with the degree of deacetylation and were reliant on acetylation patterns. Furthermore, the solubility mainly influenced the effects on the aqueous environment, with a higher solubility conducted to lower toxicity.

Aminocatalysts are More Environmentally Friendly than Hydrogen-Bonding Catalysts

The importance of asymmetric organocatalysis in contemporary organic synthesis is widely acknowledged. However, there are practically no data on the environmental safety of organocatalysts, although this aspect is crucial for the sustainability of all new materials, chemicals, and technologies. To start to fill this data-gap, a library of 26 organocatalysts containing hydrogen-bonding catalysts [(thio)ureas and squaramides] and aminocatalysts (primary or secondary amines) was evaluated for their toxicity using the naturally luminescent Vibrio fischeri bacteria (ISO assay; one of the most widely used ecotoxicity tests). Thioureas and squaramides were shown to be relatively toxic: none of them was ranked as "not harmful" (i. e., half maximal effective concentration EC₅₀ >100 mg L^-1 ), whereas the presence of the trifluoromethyl moiety increased their toxic effect. Importantly, the aminocatalysts, whose EC₅₀ values ranged from 25 to >300 mg L^-1 , could be considered remarkably more environmentally safe or green alternatives.

Life Cycle Assessment of Microplastics Reveals Their Greater Environmental Hazards than Mismanaged Polymer Waste Losses

Concern about microplastic pollution sourced from mismanaged plastic waste losses to drainage basins is growing but lacks relevant environmental impact analyses. Here, we reveal and compare the environmental hazards of aquatic macro- and microplastic debris through a holistic life cycle assessment approach. Compared to polymeric debris, microplastics, especially smaller than 10 μm, exhibit higher freshwater ecotoxicity enhanced by watersheds' high average depth and low water temperature. High microplastic concentration within drainage basins can also cause air pollution regarding particulate matter formation and photochemical ozone formation. The environmental drawbacks of plastic mismanagement are then demonstrated by showing that the microplastic formulation and removal in drinking water treatment plants can pose more than 7.44% of the total ecotoxicity effect from plastic wastes' (microplastics') whole life cycle. Specifically, these two life cycle stages can also cause more than 50% of the plastic wastes' life cycle ecotoxicity effect related to organic chemical emissions. Therefore, reducing environmentally harmful plastic losses through advanced plastic waste recycling, collection, and effective microplastic removal technologies needs future investigation.

Effect of Bauhinia monandra Kurz Leaf Preparations on Embryonic Stages and Adult Snails of Biomphalaria glabrata (Say, 1818), Schistosoma mansoni Cercariae and Toxicity in Artemia salina

Biomphalaria glabrata snails constitute the main vector of schistosomiasis in Brazil, and Bauhinia monandra Kurz, the leaves of which contain BmoLL lectin with biocidal action, is a plant widely found on continents in which the disease is endemic. This work describes the composition of B. monandra preparations and the effect on embryos and adult snails, their reproduction parameters and hemocytes. We also describe the results of a comet assay after B. glabrata exposure to sublethal concentrations of the preparations. Additionally, the effects of the preparations on S. mansoni cercariae and environmental monitoring with Artemia salina are described. In the chemical evaluation, cinnamic, flavonoid and saponin derivatives were detected in the two preparations assessed, namely the saline extract and the fraction. Both preparations were toxic to embryos in the blastula, gastrula, trochophore, veliger and hippo stages (LC₅₀ of 0.042 and 0.0478; 0.0417 and 0.0419; 0.0897 and 0.1582; 0.3734 and 0.0974; 0.397 and 0.0970 mg/mL, respectively) and to adult snails (LC₅₀ of 6.6 and 0.87 mg/mL, respectively), which were reproductively affected with decreased egg deposition. In blood cell analysis, characteristic cells for apoptosis, micronucleus and binucleation were detected, while for comet analysis, different degrees of nuclear damage were detected. The fraction was able to cause total mortality of the cercariae and did not present environmental toxicity. Therefore, B. monandra preparations are promising in combating schistosomiasis since they can control both the intermediate host and eliminate the infectious agent, besides being safe to the environment.

A Study on Safety Management Plan for Recycling of Medium-Contact Wastes via Ecotoxicity Assessment

In South Korea, hazardous characteristics of wastes to be recycled are managed through the "Environmental Impact Assessment of Recycling" system. The ecotoxicity of medium-contact recyclable wastes, that is, those in contact with soil, groundwater, surface water, etc., is managed according to this system and is determined based on whether or not they exceed an ecotoxicity value (TU) of 2.0. The ecotoxicity of wastes is tested and determined by using pretreated eluate samples according to the Official Wastes Test Standard and applying the Official Water Pollution Process Test Standard. However, no ecotoxicity management limits are stipulated for medium-contact recycling using wastes in numerous other countries. This study aims to evaluate applicability and safety of the ecotoxicity test for wastes used in medium-contact recycling and establish an efficient management plan for hazardous characteristic wastes. Target wastes for the survey were selected based on the Wastes Control Act in South Korea. Nine types of waste were selected, which are representative types of wastes to which ecotoxicity is applied. In order to secure the representativeness of the target samples, a total of 45 samples were collected by selecting 5 cases each of the 9 waste types in consideration of the type of industry and amount of waste generated. Limit exceedance was calculated for each category of hazardous substances (leaching, total content), pH, and ecotoxicity of a total of 45 samples, and was found to increase in the order of leaching 2.22% < pH 9.09% < content 31.11% < ecotoxicity 37.21%. This indicates that the limit exceedance was maximum in the ecotoxicity category. Therefore, the application of ecotoxicity limit is efficient for identifying and comprehensively managing the environmental impacts of various types of hazardous substances contained in wastes from the perspective of comprehensive toxicity.

Acaricidal Potential and Ecotoxicity of Metallic Nano-Pesticides Used against the Major Life Stages of Hyalomma Ticks

Ticks (Acari: Ixodidae) are blood-feeding parasites capable of transmitting diseases to animals (Piroplasmosis) and humans (Congo fever, Lyme disease). The non-judicious use of chemical acaricides has led to the development of acaricide-resistant ticks, making the control of ticks and tick-borne diseases difficult. This study reports the efficacy of magnesium oxide (MgO), iron oxide (Fe₂O₃), and zinc oxide (ZnO) nanoparticles (NPs) as alternatives to traditional acaricides/pesticides using in vitro tests against major representative stages of Hyalomma ticks. Nanopesticides were chemically synthesized as rods (Fe₂O₃), stars (ZnO), and spheres (MgO) and were characterized by XRD and SEM analysis. The in vitro bioassays included adult immersion, larval immersion, and larval packet tests. Non-target effects of the nanopesticides were evaluated using snails. The LC₉₀ values of Fe₂O₃ NPs (4.21, 2.83, 0.89 mg/L) were lowest followed by MgO (4.27, 2.91, 0.93 mg/L) and ZnO (4.49, 3.05, 0.69 mg/L), for the tick adult, larval and egg stages, respectively. Fe₂O₃ NPs were capable of arresting oviposition and larval hatching in the study ticks in vitro. The snail toxicity experiments revealed minimum to mild off-target effects for all nanopesticides tested. This study is the first to report the comparative efficacy of magnesium, iron, and zinc nanomaterials for toxicity in egg, adult and larval stages of Hyalomma ticks. Further studies of NPs on establishing the efficacy against ticks and safety at host-human-environment interface could lead to promising nanopesticde applications.

Grass Shrimp (Palaemonetes pugio) as a Trophic Link for Methylmercury Accumulation in Urban Salt Marshes

Grass shrimp (Palaemonetes pugio) represent a potential link in the transfer of methylmercury (MeHg) from salt marsh sediments to transient young-of-the-year (YOY) fish. Across six salt marshes subject to varying degrees of Hg contamination, MeHg concentration in grass shrimp was significantly correlated with MeHg in sediment (p < 0.05, R² = 0.81). Bioenergetic models show that grass shrimp alone account for 12-90% of MeHg observed in YOY striped bass and 6-22% of MeHg in YOY summer flounder. Direct accumulation of MeHg from grass shrimp to YOY fish increased with MeHg levels in grass shrimp and sediment. However, in the most contaminated salt marshes with the highest levels of MeHg in grass shrimp and sediment, indirect accumulation of MeHg from grass shrimp by YOY summer flounder, whose diet is dominated by benthic forage fish (mummichog), is predicted to plateau because higher concentrations of MeHg in grass shrimp are offset by a lower proportion of grass shrimp in the mummichog diet. Our results demonstrate that grass shrimp are an important trophic link in the bioaccumulation of MeHg in salt marsh food webs and that MeHg accumulation in YOY fish varies with both the concentration of MeHg in salt marsh sediments and benthic food web structure.

Nanosafety Analysis of Graphene-Based Polyester Resin Composites on a Life Cycle Perspective

The use, production, and disposal of engineering nanomaterials (ENMs), including graphene-related materials (GRMs), raise concerns and questions about possible adverse effects on human health and the environment, considering the lack of harmonized toxicological data on ENMs and the ability of these materials to be released into the air, soil, or water during common industrial processes and/or accidental events. Within this context, the potential release of graphene particles, their agglomerates, and aggregates (NOAA) as a result of sanding of a battery of graphene-based polyester resin composite samples intended to be used in a building was examined. The analyzed samples were exposed to different weathering conditions to evaluate the influence of the weathering process on the morphology and size distribution of the particles released. Sanding studies were conducted in a tailored designed sanding bench connected to time and size resolving measurement devices. Particle size distributions and particle number concentration were assessed using an optical particle counter (OPC) and a condensation particle counter (CPC), respectively, during the sanding operation. A scanning electron microscope/energy dispersive X-ray (SEM/EDX) analysis was performed to adequately characterize the morphology, size, and chemical composition of the released particles. A toxicity screening study of pristine and graphene-based nanocomposites released using the aquatic macroinvertebrate Daphnia magna and relevant human cell lines was conducted to support risk assessment and decision making. The results show a significant release of nanoscale materials during machining operations, including differences attributed to the % of graphene and weathering conditions. The cell line tests demonstrated a higher effect in the human colon carcinoma cell line Caco2 than in the human fibroblasts (A549 cell line), which means that composites released to the environment could have an impact on human health and biota.

Dispersion Stability of 14 Manufactured Nanomaterials for Ecotoxicity Tests Using Raphidocelis subcapitata

The development of nanotechnology has increased concerns about the exposure of ecosystems to manufactured nanomaterials, the toxicities of which are now being researched. However, when manufactured nanomaterials are mixed with algae in a culture medium for ecotoxicity tests, the results are vulnerable to distortion by an agglomeration phenomenon. Here, we describe a dispersion method commonly applicable to ecotoxicity tests for the 14 types of manufactured nanomaterials specified by the Organisation of Economic Co-operation and Development’s Sponsorship Programme, namely aluminum oxide (Al₂O₃), carbon black, single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), cerium oxide (CeO₂), dendrimers, fullerene, gold (Au), iron (Fe), nanoclays, silver (Ag), silicon dioxide (SiO₂), titanium dioxide (TiO₂), and zinc oxide (ZnO). The type of dispersant, sonication time, and stirring speed were carefully considered. Consequently, 1500 mg/L of gum arabic was selected as a dispersant; for sonication time, 1 h was selected for dendrimers, 2 h for SiO₂, 24 h for SWCNTs and Au, and 4 h for the other nanomaterials. Dispersion stability was achieved for all materials at a stirring speed of 200 rpm. To verify the effect of this dispersion method on ecotoxicity tests, toxicity was measured through cell counts for SWCNTs and TiO₂ using Raphidocelis subcapitata. The half-maximal effective concentrations (EC₅₀) were 18.0 ± 4.6 mg/L for SWCNTs and 316.6 ± 64.7 mg/L for TiO₂.

Evaluation of the Toxicity and Sublethal Effects of Acetamiprid and Dinotefuran on the Predator Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae)

Neonicotinoid insecticides affect the physiology or behavior of insects, posing risks to non-target organisms. In this study, the effects of sublethal doses of two neonicotinoid insecticides, acetamiprid and dinotefuran, against Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae) were determined and compared. The results showed that acetamiprid and dinotefuran at LD₁₀ (8.18 ng a.i. per insect and 9.36 ng a.i. per insect, respectively) and LD₃₀ (16.84 ng a.i. per insect and 15.01 ng a.i. per insect, respectively) significantly prolonged the larval stages and pupal stages (except acetamiprid LD₁₀), compared to control. In addition, acetamiprid and dinotefuran at LD₃₀ significantly prolonged the adult preoviposition period (APOP) and total preoviposition period (TPOP). In contrast, the two insecticides at LD₁₀ and LD₃₀ had no significant effect on the longevity, fecundity, reproductive days, preadult survival rate (%), intrinsic rate of increase (r), net reproductive rate (R₀), and finite rate of increase (λ). These results provide a theoretical basis for the rational use of these two insecticides and the utilization and protection of C. pallens.

Ecotoxicity and Biodegradation of Sustainable Environment-Friendly Bone-Glue-Based Adhesive Suitable for Insulation Materials

Bone glue with sodium lignosulfonate is a protein-based adhesive. Their combination leads to strong binding necessary for the achievement of adhesive properties. However, biodegradation and ecotoxicity of materials composed of bone glue and sodium lignosulfonate has never been studied before. In this paper, the biodegradation potential of the mixture of bone glue, lignosulfonate and rape straw modified by water or NaOH on an agar test with aerial molds and in acute aquatic tests with mustard, yeasts, algae and crustaceans was analyzed. Epoxy resin as an ecologically unfriendly binder was used as a negative control and pure rape straw as a background. The results indicated that all samples were covered by molds, but the samples containing straw treated by NaOH showed lower biodegradability. The ecotoxicological effects varied among the applied model organisms. Artemia salina was not able to survive and S. alba could not prolong roots in the eluates of all samples (100% inhibition). Freshwater algae (D. subspicatus) were not significantly affected by the samples (max. 12% inhibition, max. 16% stimulation). The biomass of yeasts (S. cerevisae) was strongly stimulated in the presence of eluates in a comparison to control (max. 38% stimulation).

Comparative Study of Algae-Based Measurements of the Toxicity of 14 Manufactured Nanomaterials

With the increasing use of nanomaterials in recent years, determining their comparative toxicities has become a subject of intense research interest. However, the variety of test methods available for each material makes it difficult to compare toxicities. Here, an accurate and reliable method is developed to evaluate the toxicity of manufactured nanomaterials, such as Al₂O₃, carbon black, single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), CeO₂, dendrimers, fullerene, gold, iron, nanoclays, silver, SiO₂, TiO₂, and ZnO. A series of 72 h chronic and 8 h acute toxicity tests was performed using cell counting, chlorophyll, and delayed fluorescence methods. Comparable toxicities using the chlorophyll and delayed fluorescence methods were impossible to determine because the EC₅₀ of some of the nanomaterials could not be measured. All three test methods were successfully applied to the chronic toxicity tests of manufactured nanomaterials, and cell counting was the only method applicable to acute toxicity tests. The toxicity data and the proposal of measurement method for manufactured nanomaterials obtained in this study can be helpful for preparing exposure standards and investigating the toxicities of other nanomaterials in the future.

Toward Assessing Absolute Environmental Sustainability of Chemical Pollution

Chemicals are widely used in modern society, which can lead to negative impacts on ecosystems. Despite the urgent relevance for global policy setting, there are no established methods to assess the absolute sustainability of chemical pressure at relevant spatiotemporal scales. We propose an absolute environmental sustainability framework (AESA) for chemical pollution where (1) the chemical pressure on ecosystems is quantified, (2) the ability for ecosystems to withstand chemical pressure (i.e., their carrying capacity) is determined, and (3) the "safe space" is derived, wherein chemical pressure is within the carrying capacity and hence does not lead to irreversible adverse ecological effects. This space is then allocated to entities contributing to the chemical pressure. We discuss examples involving pesticide use in Europe to explore the associated challenges in implementing this framework (e.g., identifying relevant chemicals, conducting analyses at appropriate spatiotemporal scales) and ways forward (e.g., chemical prioritization approaches, data integration). The proposed framework is the first step toward understanding where and how much chemical pressure exceeds related ecological limits and which sources and actors are contributing to the chemical pressure. This can inform sustainable levels of chemical use and help policy makers establish relevant and science-based protection goals from regional to global scale.

Co-Exposure of Nanopolystyrene and Other Environmental Contaminants-Their Toxic Effects on the Survival and Reproduction of Enchytraeus crypticus

Plastics in all shapes and sizes have become widespread across ecosystems due to intense anthropogenic use. As such, they can interact with other contaminants that accumulate in the terrestrial environment, such as pharmaceuticals, metals or nanomaterials (NMs). These interactions can potentiate combined toxic effects in the exposed soil organisms, with hazardous long-term consequences to the full ecosystem. In the present study, a terrestrial model species, Enchytraeus crypticus (oligochaeta), was exposed through contaminated soil with nanopolystyrene (representative of nanoplastics (NPls)), alone and in combination with diphenhydramine (DPH, representative of pharmaceuticals), silver nitrate (AgNO₃, representative of metals) and vanadium nanoparticles (VNPs, representative of NMs). AgNO₃ and VNPs decreased E. crypticus reproduction at 50 mg/kg, regardless of the presence of NPls. Moreover, at the same concentration, both single and combined VNP exposures decreased the E. crypticus survival. On the other hand, DPH and NPls individually caused no effect on organisms' survival and reproduction. However, the combination of DPH (10 and 50 mg/kg) with 300 mg NPls/kg induced a decrease in reproduction, showing a relevant interaction between the two contaminants (synergism). Our findings indicate that the NPls can play a role as vectors for other contaminants and can potentiate the effects of pharmaceuticals, such as DPH, even at low and sub-lethal concentrations, highlighting the negative impact of mixtures of contaminants (including NPls) on soil systems.

Activities of Microplastics (MPs) in Agricultural Soil: A Review of MPs Pollution from the Perspective of Agricultural Ecosystems

Microplastics are emerging persistent pollutants which have attracted increasing attention worldwide. Although microplastics have been widely detected in aquatic environments, their presence in soil ecosystems remains largely unexplored. Plastic debris accumulates in farmland, causing serious environmental problems, which may directly affect food substances or indirectly affect the members in each trophic level of the food chain. This review summarizes the origins, migration, and fate of microplastics in agricultural soils and discusses the interaction between microplastics and the components in farmland from the perspectives of toxicology and accumulation and deduces impacts on ecosystems by linking the organismal response to an ecological role. The effects on farmland ecosystem function are also discussed, emphasizing the supply of agricultural products, food chain pathways, carbon deposition, and nitrogen cycling and soil and water conservation, as microplastic pollution will affect agricultural ecosystems for a long period, posing an ecological risk. Finally, several directions for future research are proposed, which is important for reducing the effect of microplastics in agricultural systems.

The Road to Achieving the European Commission's Chemicals Strategy for Nanomaterial Sustainability-A PATROLS Perspective on New Approach Methodologies

The European Green Deal outlines ambitions to build a more sustainable, climate neutral, and circular economy by 2050. To achieve this, the European Commission has published the Chemicals Strategy for Sustainability: Towards a Toxic-Free Environment, which provides targets for innovation to better protect human and environmental health, including challenges posed by hazardous chemicals and animal testing. The European project PATROLS (Physiologically Anchored Tools for Realistic nanOmateriaL hazard aSsessment) has addressed multiple aspects of the Chemicals Strategy for Sustainability by establishing a battery of new approach methodologies, including physiologically anchored human and environmental hazard assessment tools to evaluate the safety of engineered nanomaterials. PATROLS has delivered and improved innovative tools to support regulatory decision-making processes. These tools also support the need for reducing regulated vertebrate animal testing; when used at an early stage of the innovation pipeline, the PATROLS tools facilitate the safe and sustainable development of new nano-enabled products before they reach the market.

Environmental Consequences of Rubber Crumb Application: Soil and Water Pollution

End-of-life tires are utilized for various purposes, including sports pitches and playground surfaces. However, several substances used at the manufacture of tires can be a source of concerns related to human health or environment’s adverse effects. In this context, it is necessary to map whether this approach has the desired effect in a broader relation. While the negative effects on human health were investigated thoroughly and legislation is currently being revisited, the impact on aquatic or soil organisms has not been sufficiently studied. The present study deals with the exposure of freshwater and soil organisms to rubber crumb using the analysis of heavy metal and polycyclic aromatic hydrocarbon concentrations. The obtained results refer to substantial concerns related to freshwater contamination specifically, since the increased concentrations of zinc (7 mg·L⁻¹) and polycyclic aromatic hydrocarbons (58 mg·kg⁻¹) inhibit the growth of freshwater organisms, Desmodesmus subspicatus, and Lemna minor in particular. The performed test with soil organisms points to substantial concerns associated with the mortality of earthworms as well. The acquired knowledge can be perceived as a roadmap to a consistent approach in the implementation of the circular economy, which brings with it a number of so far insufficiently described problems.

Biodegradation of PBSA Films by Elite Aspergillus Isolates and Farmland Soil

Plastic films are widely used in current agricultural practices; however, most mulch films used are discarded and buried in the land after harvest, having adverse environmental impacts. To solve this environmental problem, the demand for biodegradable mulch has been increasing in recent years. Polybutylene succinate-co-adipate (PBSA) is a biodegradable polymer with good ductility and can be used for packaging and mulching. In this study, we isolated two elite fungal strains for PBSA degradation from farmlands, i.e., Aspergillus fumigatus L30 and Aspergillus terreus HC, and the latter showed better degradation ability than the former. It is noteworthy that biodegradation of PBSA by A. terreus is reported for the first time, which revealed unique characteristics. In the soil burial test, even the soil with relatively poor degradation ability could be improved by the addition of elite fungal mycelia. In substrate specificity analyses of soil samples, PBSA could induce the synthesis of lipolytic enzymes of indigenous microbes to degrade substrates with medium and long carbon chains in soil. Furthermore, PBSA residues or fungal mycelia supplementation in soils had no adverse effect on the seed germination rate, seedling growth, or mature plant weight of the test green leafy vegetable. Taken together, the results of this study not only advance our understanding of the biodegradation of PBSA films by filamentous fungi but also provide insight into improving the efficiency of biodegradation in soil environments.