Fosthiazate, a soil-applied nematicide, induces oxidative stress, neurotoxicity and transcriptome aberrations in earthworm (Eisenia fetida)

Understanding phytotoxicity of fosthiazate on crop seedlings through uptake kinetics, ROS burst and chloroplast metabolism

As a crucial management strategy for crop diseases, pests and weeds, the use of pesticides can also have some adverse effects on plant health. Understanding the specific mechanisms is essential for developing effective mitigation measure. However, most studies on phytotoxicity mechanism have focused on ionic balance and biochemical responses, with little consideration given to pesticide distributions within plants. Herein, symptoms and the underlying mechanisms of fosthiazate phytotoxicity to crops represented by tomatoes were investigated. Necrotic leaf edge and the root inhibition of tomato seedlings was observed after fosthiazate soil applied at the maximum registered dose. Given its high hydrophilicity, fosthiazate dissolved in soil solution was readily absorbed by plant roots and efficiently translocated upward via the transpiration stream, leading to varying concentrations across different organs and thus differential phytotoxicity. As fosthiazate accumulates, it induced plasmolysis, triggered reactive oxygen species (ROS) bursts, and disrupted photosynthesis, resulting in leaf wilting and necrotic. The interference of sucrose synthesis, transport and metabolism further inhibited root growth. Fosthiazate-loaded microcapsules could alleviate its phytotoxicity by slowing down the release rate. Our findings provided an important basis for the improvement of pesticide application safety and guiding the development of chemicals targets at specific organisms.

Chlorantraniliprole-induced oxidative stress, DNA damage, and apoptosis in Caenorhabditis elegans: Mechanistic insights and ecological risk implications

Chlorantraniliprole (CAP) is one of the most widely used insecticides in the world. CAP is strictly restricted in foodstuff with maximum residual limits (MRLs) from 0.01 to 40 mg/kg set by Chinese national food safety standard. However, a detailed evaluation on its possible acute toxicity and the underlying mechanisms remains inconclusive. In this study, effects of CAP at environmentally relevant concentrations on growth, locomotion, lifespan, reproduction, and antioxidative defense systems were evaluated using the model organism Caenorhabditis elegans. Exposure to CAP notably reduced nematode development, head thrash, and pharyngeal pumping frequency compared with the control. Moreover, CAP at 0.1, 1, and 10 μg/L decreased lifespan of nematodes by 23.73 %, 28.71 %, and 36.23 %, respectively. CAP at 1 and 10 μg/L enhanced the ROS level, reduced the activity of antioxidative enzyme, including CAT and SOD. CAP also regulated mRNA expression levels of daf-16, skn-1, sod-3, gst-4, ced-3, ced-4, ced-9, egl-1, clk-2, and hus-1 in the nematodes, while no significant effect in the mutants was observed. Pearson correlation analysis revealed that significant correlation existed between tested parameters, indicating that CAP caused a series of negative effects in the nematodes. Meanwhile, molecular docking results revealed the potential of CAP to bind with oxidative stress, DNA damage and apoptosis proteins, providing molecular mechanisms for the observed detrimental effects. Therefore, our results suggested that acute exposure to CAP at environmental concentrations caused oxidative stress, DNA damage and apoptosis in the nematodes. Our results shed new light on risk assessment and management of CAP.

Meta-analysis of endocrine-disrupting chemical effects on earthworm functional traits

Endocrine-disrupting chemicals (EDCs) are ubiquitous emerging environmental contaminants. However, the comprehensive impact of EDCs on soil ecosystems, particularly on the model organism Eisenia fetida, remains inadequately understood due to disparate experimental and assessment methods. A meta-analysis was conducted to analyze the effects of EDCs on earthworm functional traits, including survival, behavior, growth, reproduction, and cellular responses. The analysis revealed that EDCs significantly impaired earthworm survival (-17.5%, p < 0.05), behavior (-62.2%, p < 0.001), growth (-11.5%, p < 0.001), and reproduction (-36.7%, p < 0.001). EDCs induced substantial oxidative stress, evidenced by a 36.5% (p < 0.001) increase in reactive oxygen species (ROS) production and elevated oxidative damage. The antioxidant defense system showed compensatory activation, with enhanced superoxide dismutase (10.0%) and catalase (8.90%) activities and glutathione levels (23.3%) (p < 0.001). The present study found chemical-specific toxicity patterns with heavy metals causing the most severe effects on behavior and reproduction. Toxicity profiles varied with exposure concentration and duration, revealing complex dose-response and temporal relationships. These findings provide crucial insights for the ecological risk assessment of EDCs and establish a foundation for developing targeted mitigation strategies. Furthermore, the findings highlight the importance of taking multiple endpoints into account when evaluating the toxicity of EDCs and suggest possible directions for future research.

Combined effects of microplastics and flupyradifurone on gut microbiota and oxidative status of honeybees (Apis mellifera L.)

The increasing accumulation of polystyrene microplastics (PS-MPs) and the widespread use of flupyradifurone (FPF) affect honeybee health adversely. However, the combined impact of PS-MPs and FPF toxicity on honeybees remains unknown. In this study, honeybee (Apis mellifera L.) was fed with sucrose solutions containing PS-MPs (0.5 or 5 μm, 50 mg/L), FPF (4 mg/L), or their combination for 21 days under laboratory conditions. The effects of PS-MPs and FPF on honeybee physiology, gut microbiota, and stress-related enzyme activities and genes were measured. The findings showed that concurrent exposure to PS-MPs and FPF significantly reduced honeybee survival, with additive effects, decreased sucrose consumption and body weight, and devastated midgut epithelial cells. FPF was the main stressor affecting survival, while PS-MPs exerted a greater influence on body weight. Co-exposure to PS-MPs (0.5 μm) and FPF disrupted gut microbiota, significantly decreasing Lactobacillus abundance. Supplementation with Lactobacillus helsingborgensis improved honeybee survival, highlighting the protective role of gut microbiota. PS-MPs exposure, alone or combined with FPF, increased oxidative stress and decreased detoxification and immune capabilities in honeybees. These findings suggested the combined toxicity of PS-MPs and FPF on honeybees, underscoring the potential ecology risk posed by multiple stressors.

Ecotoxicological effects of the neonicotinoid insecticide dinotefuran on springtails (Folsomia candida) at soil residual concentration

Dinotefuran, a third-generation neonicotinoid insecticide, is widely used in agriculture production due to its excellent insecticidal efficacy. Considering its persistence and high toxicity in soil, it is essential to evaluate its low-dose toxic effects on non-target soil organisms such as the springtail (Folsomia candida). The results revealed that the 7-day half lethal concentration (7d-LC50) of dinotefuran contact toxicity to springtails was 0.029 μg cm-2. Its chronic toxicity in 4 soil types was ranked as: red soil (0.021 mg kg-1) > fluvo-aquic soil (0.040 mg kg-1) > artificial soil (0.049 mg kg-1) > black soil (0.085 mg kg-1). Soil organic matter (SOC), pH, and total nitrogen (TN) were identified as critical factors affecting dinotefuran toxicity. Biochemical assay results showed that environmental concentrations (0.2-1.6 mg kg-1) of dinotefuran induced oxidative stress and oxidative damage in springtails. Oxidative stress-related enzymes (including superoxide dismutase (SOD) and catalase (CAT)) and detoxification enzymes were subjected to initial activation at low dinotefuran concentrations, inhibition and re-activation at high concentration. Target enzyme acetylcholinesterase (AChE), malondialdehyde (MDA) content, and total protein content were inhibited with prolonged exposure time and increasing concentrations of dinotefuran. Molecular docking analysis showed that dinotefuran bound to the active sites of related enzymes, thus disrupting their structure and functions, eventually resulting in damages to physiological functions of springtails. In summary, this study deciphers the dinotefuran toxicological mechanism on soil springtails at environmental concentrations. Our findings lay theoretical basis for further assessing its pollution risk and managing its application.

Comparison of the combined toxicity of PFOA and emerging alternatives: A comprehensive evaluation of oxidative damage, apoptosis and immunotoxicity in embryonic and adult zebrafish

Perfluorohexanoic acid (PFHxA) and perfluorobutanoic acid (PFBA) are widely used substitutes to perfluorooctanoic acid (PFOA). Whether these substitutes are less toxic than PFOA remains unclear owing to differences in the experimental methods, test organisms, and other experimental conditions in previous studies. The present study selected 0.5 and 5 μg L-1 as the test concentrations and simultaneously compared the combined toxicity of the substitutes and PFOA in terms of oxidative damage, neurotoxicity, apoptosis, and immunotoxicity in two developmental stages of zebrafish (adult and embryos) under the same test conditions. The results indicated that in both adult and embryonic zebrafish, PFHxA, PFBA, and PFOA disrupt redox homeostasis, stimulate cell proliferation, and lead to carcinogenesis. The mechanisms by which PFHxA and PFOA induce neurotoxicity and immunotoxicity were similar. Molecular docking analysis showed that the substitutes and PFOA stably attached to proteins and changed their structure and function. The obtained integrated biomarker response index values indicated that the toxicity of PFHxA, PFBA, and PFOA in zebrafish increased with increasing concentrations; PFHxA was more toxic than PFOA. The present study clarified the ecotoxicity of PFHxA and PFBA in zebrafish and simultaneously compared the differences in toxicity between the substitutes and PFOA to zebrafish, providing a robust scientific basis for the clarification and selection of safe substitutes to PFOA.

Evaluating point source pesticide contamination via sprayer washing water dispersal: A northern Italian vineyard area case study

Wastewater contaminated by plant protection products (PPP) from sprayer cleaning operations must be properly managed and disposed of, as it could represent a point source of environmental PPP pollution and pose risks to non-target organisms. Three conventionally and two organically managed farms in hilly vineyards of North-West Italy engaged in a participatory activity for sampling sprayer washing and resultant water. In total 52 samples of wash water (internal and external) were collected during two agricultural seasons and analyzed for six organic pesticides and metallic Cu. PPP concentrations in water collected after internal washing were up to 37.9 times higher than in water collected after external washing. Concentrations in water after external washing were surprisingly high. This may be explained by the characteristics of the sprayers, but also by farmers failing to comply with good practices during PPP use. To evaluate the possible impact on the aquatic environment of dispersal of wash water into a water body, the FOCUS "Stream" approach was followed. The concentrations thus estimated were almost always higher than the environmental quality standard for surface waters but below the toxicological endpoints for fish and Daphnia magna. With reference to the Italian guidelines for waste classification, only one sample would be classified as ecotoxicological hazardous waste and need to be properly managed. In conclusion, due to the nature of contamination, which is point source but diffuse in the territory, analytical data confirms the need for additional joint efforts to improve awareness in managing wastewater containing PPP and to decrease the impact of the agricultural sector.

Naturally-occurring nematicides of plant origin: two decades of novel chemistries

Plant-parasitic nematodes are among the most destructive plant pathogens, resulting in a global annual economic loss of about 358 billion dollars. Using synthetic nematicides to control plant-parasitic nematodes has resulted in broad-spectrum toxicity to the environment. Plant-derived secondary metabolites have recently emerged as viable options that provide effective, greener, and renewable routes for managing plant-parasitic nematodes in various cropping systems. However, limited comprehensive information on plant-derived secondary metabolites sources, chemical structures, and nematicidal activities is available. This study aims to compile and analyze data on plant-based secondary metabolites with nematicidal properties collected over the last two decades. In this review, we identified 262 plant-based metabolites with nematicidal activities that were isolated from 35 plant families and 65 plant species. Alkaloids, terpenoids, saponins, flavonoids, coumarins, thiophenes, and annonaceous acetogenins were among the most studied compounds. In addition to the structure-activity relation for specific metabolites with nematicidal potency, various techniques for their extraction and isolation from plant material are discussed. Our findings demonstrate the potential of plants as a feedstock for sourcing nematicidal compounds and discovering new chemistries that could potentially be used for developing the next generation of nematicides. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Nano-biochar reduces sustainable remediation of cadmium-contaminated soil more than micro-biochar: Evidence from cadmium removal and Eisenia foetida toxicity

Micro- (M-BC) and nano-biochar (N-BC) particles are ready to be disintegrated from biochar (BC), which is extensively applied to remediate heavy metal-contaminated soil. Still, its effects on the remediation efficiency remain poorly understood. This study investigated the interactions between the BC particles (M-BC and N-BC) and Eisenia foetida (E. foetida) in cadmium (Cd)-contaminated soils. Results indicated that M-BC has weak negative effect on E. foetida with survival rates of ≥85% as it is failed to be internalized. The interactive effects between M-BC/N-BC and Cd reduced the mobility of Cd, leading to low avoidance behavior of E. foetida. The synergistic effect of 0.1% M-BC and E. foetida caused pH regulation, BC diffusion and alternation of soil microbial community in the soil. This favored the remediation of Cd-contaminated soils with 56.2% Cd fixation efficiency identified. Conversely, internalization of Cd-loaded N-BC by E. foetida was recorded when 0.1% N-BC was amended in the soil. This triggered DNA damage, antioxidant suppression, antiapoptotic inhibition, digestion impairment, reproductive decline, and survival rates reduction (55%) in E. foetida, indicating the essential role of E. foetida in the soil is likely to be depressed. These findings are helpful to understand the potential negative effects of BC application in soil remediation.

Ecotoxicological risk of co-exposure to fosthiazate and microplastics on earthworms (Eisenia fetida): Integrating biochemical and transcriptomic analyses

Fosthiazate (FOS) is a widely used organophosphorus insecticide effective against soil root-knot nematodes. However, its ecotoxicity to non-target soil organisms, particularly in combination with microplastics (MPs), is unclear. This study explores the toxic-effects and molecular mechanisms of co-exposure to FOS and MPs on earthworms (Eisenia fetida) using multilevel toxicity endpoints and transcriptomics. Results showed that both FOS and MPs elevated the intracellular levels of reactive oxygen species (ROS), malondialdehyde (MDA), and 8-hydroxy-2-deoxyguanosine (8-OHdG) in earthworms' cells. The superoxide dismutase (SOD) and catalase (CAT) activities followed a similar trend in all treatments, with changes observed at 14 and 28 days, indicating that co-exposure to FOS and MPs increased DNA oxidative damage. Notably, the co-exposure more significantly inhibited Ca2+-ATPase activity and exacerbated neurotoxicity compared to individual treatments, closely associated with changes in intracellular ROS levels that mediate neuroinhibition and lead to neurotoxicity. KEGG enrichment analysis revealed that MPs and FOS disrupted pathways related to metabolism, immunity, and apoptosis, while co-exposure primarily impaired endocrine and receptor pathways, showing higher toxicity. Our study offers novel insights into the ecotoxicological effects and mechanisms of pesticides and microplastics on earthworms, providing valuable data for evaluating the soil environmental health risks associated with compound pollution.

Butyl benzyl phthalate induces neurotoxicity in Eisenia fetida: Mechanisms revealed by biochemical and metabolomic analyses

Phthalates, particularly butyl benzyl phthalate (BBP), are ubiquitous environmental contaminants with potential neurotoxic effects. However, their impact on soil organisms, especially earthworms (Eisenia fetida), remains poorly understood. The current study investigated the neurotoxic effects of BBP on Eisenia fetida in artificial and red soils using an integrated approach combining biochemical assays, metabolomics, and molecular docking. Earthworms were exposed to 0, 1, and 10 mg kg-1 BBP for 14 and 28 days. Biochemical assays revealed significant increases in oxidative stress markers and disruptions in neurotransmission-related enzyme activities. Metabolomic analysis of the cerebral ganglia identified alterations in energy metabolism, lipid metabolism, and neuroactive ligand-receptor interaction signaling pathways. Molecular docking studies corroborated these findings, showing strong interactions between BBP and essential neuronal proteins, particularly the sodium pump. The integration of these data suggests that BBP-induced neurotoxicity in Eisenia fetida is primarily mediated by calcium signaling pathway dysfunction and calcium homeostasis imbalance. Notably, neurotoxic effects were more pronounced in red soil than in artificial soil, highlighting the importance of considering soil type in ecotoxicological assessments. The current study provides novel insights into the mechanisms of BBP-induced neurotoxicity in soil invertebrates and underscores the potential ecological risks associated with phthalate contamination in agricultural environments.

Fluxapyroxad induced toxicity of earthworms: Insights from multi-level experiments and molecular simulation studies

Fluxapyroxad, an emerging succinate dehydrogenase inhibitor fungicide, is widely used due to its excellent properties. Given its persistence in soil with a 50 % disappearance time of 183-1000 days, it is crucial to evaluate the long-term effects of low-dose fluxapyroxad on non-target soil organisms such as earthworms (Eisenia fetida). The present study investigated the impacts of fluxapyroxad (0.01, 0.1, and 1 mg kg-1) on Eisenia fetida over 56 days, focusing on oxidative stress, digestive and nervous system functions, and histopathological changes. We also explored the mechanisms of fluxapyroxad-enzyme interactions through molecular docking and dynamics simulations. Results demonstrated a significant dose-response relationship in the integrated biomarker response of 12 biochemical indices. Fluxapyroxad altered expression levels of functional genes and induced histopathological damage in earthworm epidermis and intestines. Molecular simulations revealed that fluxapyroxad is directly bound to active sites of critical enzymes, potentially disrupting their structure and function. Even at low doses, long-term fluxapyroxad exposure significantly impacted earthworm physiology, with effects becoming more pronounced over time. Our findings provide crucial insights into the chronic toxicity of fluxapyroxad and emphasize the importance of long-term, low-dose studies in pesticide risk assessment in soil. This research offers valuable guidance for the responsible management and application of fungicides.

Leaching behavior of microplastics during sludge mechanical dewatering and its effect on activated sludge

Dewatering is an indispensable link in sludge treatment, but its effect on the microplastics (MPs) remains inadequately understood. This study investigated the physicochemical changes and leaching behavior of MPs during the mechanical dewatering of sludge, as well as the impact of MP leachates on activated sludge (AS). After sludge dewatering, MPs exhibit rougher surfaces, decreased sizes and altered functional groups due to the addition of dewatering agents and the application of mechanical force. Meanwhile, plastic additives, depolymerization products, and derivatives of their interactions are leached from MPs during sludge dewatering process. The concentration of MP-based leachates in sludge is 2-25 times higher than that in water. The enhancement of pH and ionic strength caused by dewatering agents induces the release of MP leachates enriched with protein-like, fulvic acid-like, and soluble microbial by-product-like substances. The reflux of MP leachates in sludge dewatering liquor to the wastewater treatment system negatively impacts AS, leading to a decrease in COD removal rate and inhibition of the extracellular polymeric substances secretion. More importantly, MP leachates cause oxidative stress to microbial cells and alter the microbial community structure of AS at the phylum and genus levels. These findings confirm that MPs undergo aging and leaching during sludge dewatering process, and MP leachates may negatively affect the wastewater treatment system.

Pseudomonas putida HE alleviates glyphosate-induced toxicity in earthworm: Insights from the neurological, reproductive and immunological status

The proceeding study aimed to isolate glyphosate-degrading bacteria from soil and determine optimal degradation conditions through single-factor experiments and response surface methodology. The detoxifying efficacy of the isolate on glyphosate was assessed using earthworm model. The results indicate that Pseudomonas putida HE exhibited the highest glyphosate degradation rate. Optimal conditions for glyphosate degradation were observed at an inoculation percentage of approximately 5%, a pH of 7, and a temperature of 30 °C. Glyphosate induced notable neurotoxicity and reproductive toxicity in earthworms, evidenced by reduced activity of the neurotoxicity-associated enzyme AChE. Additionally, an increase in the activities of catalase, superoxide dismutase, and lactate dehydrogenase was observed. H&E staining revealed structural disruptions in the earthworm clitellum, with notable atrophy in the structure of spermathecae. Furthermore, glyphosate activation of earthworm immune systems led to increased expression of immune-related genes, specifically coelomic cytolytic factor and lysozyme. Notably, the introduction of strain HE mitigated the glyphosate toxicity to the earthworms mentioned above. P. putida HE was able to increase soil enzyme activities that were reduced due to glyphosate. The isolate P. putida HE, emerged as an effective and cost-efficient remedy for glyphosate degradation and toxicity reduction in natural settings, showcasing potential applications in real ecological settings.

Ecological risk assessment of castor oil based waterborne polyurethane: Mechanism of anionic/cationic state selective toxicity to Eisenia fetida

Cationic and anionic castor oil-based waterborne polyurethanes (C-WPU/A and C-WPU/C) have great potential for development in agriculture. However, it is still unclear whether these polyurethanes are harmful or toxic to soil fauna. Based on multilevel toxicity endpoints and transcriptomics, we investigated the effects of C-WPU/A and C-WPU/C on earthworms (Eisenia fetida). The acute toxicity results showed that C-WPU/A was highly toxic to the earthworms, whereas C-WPU/C was nearly nontoxic. C-WPU/A significantly affected the body weight, burrowing ability and cocoon production rate of earthworms compared to C-WPU/C. After exposure to C-WPU/A, the results showed accumulation of reactive oxygen species (ROS), abnormal peroxidase activity, and increased malondialdehyde levels. Additionally, more serious histopathological damage was observed in earthworms, such as epidermal damage, vacuolization, longitudinal muscle disorganization, and shedding of intestinal epidermal cells. At the cellular level, C-WPU/A induced more severe lysosomal damage, DNA damage and apoptosis than C-WPU/A. C-WPU/A made more differentially expressed genes and considerably more enriched pathways at the transcriptional level than C-WPU/C. These pathways are largely involved in cell membrane signaling, detoxification, and apoptosis. These results provide an important reference for elucidating the selective toxicity mechanisms of C-WPU/A and C-WPU/C in earthworms.

Sensitive Coatings Based on Molecular-Imprinted Polymers for Triazine Pesticides' Detection

Triazine pesticide (atrazine and its derivatives) detection sensors have been developed to thoroughly check for the presence of these chemicals and ultimately prevent their exposure to humans. Sensitive coatings were designed by utilizing molecular imprinting technology, which aims to create artificial receptors for the detection of chlorotriazine pesticides with gravimetric transducers. Initially, imprinted polymers were developed, using acrylate and methacrylate monomers containing hydrophilic and hydrophobic side chains, specifically for atrazine, which shares a basic heterocyclic triazine structure with its structural analogs. By adjusting the ratio of the acid to the cross-linker and introducing acrylate ester as a copolymer, optimal non-covalent interactions were achieved with the hydrophobic core of triazine molecules and their amino groups. A maximum sensor response of 546 Hz (frequency shift/layer height equal to 87.36) was observed for a sensitive coating composed of 46% methacrylic acid and 54% ethylene glycol dimethacrylate, with a demonstrated layer height of 250 nm (6.25 kHz). The molecularly imprinted copolymer demonstrated fully reversible sensor responses, not only for atrazine but also for its metabolites, like des-ethyl atrazine, and structural analogs, such as propazine and terbuthylazine. The efficiency of modified molecularly imprinted polymers for targeted analytes was tested by combining them with a universally applicable quartz crystal microbalance transducer. The stable selectivity pattern of the developed sensor provides an excellent basis for a pattern recognition procedure.

Novel Insights into Stereoselective Reproductive Toxicity Induced by Mefentrifluconazole in Earthworms (Eisenia fetida): First Report of Estrogenic Effects

Widespread use of the new chiral triazole fungicide mefentrifluconazole (MFZ) poses a threat to soil organisms. Although triazole fungicides have been reported to induce reproductive disorders in vertebrates, significant research gaps remain regarding their impact on the reproductive health of soil invertebrates. Here, reproduction-related toxicity end points were explored in earthworms (Eisenia fetida) after exposure for 28 d to soil containing 4 mg/kg racemic MFZ, R-(-)-MFZ, and S-(+)-MFZ. The S-(+)-MFZ treatment resulted in a more pronounced reduction in the number of cocoons and juveniles compared to R-(-)-MFZ treatment, and the expression of annetocin gene was significantly downregulated following exposure to both enantiomers. This reproductive toxicity has been attributed to the disruption of ovarian steroidogenesis at the transcriptional level. Further studies revealed that MFZ enantiomers were able to activate the estrogen receptor (ER). Indirect evidence for this estrogenic effect is provided by the introduction of 17β-estradiol, which also induces reproductive disorders through ER activation.

Assessment of toxic effects of thallium on the earthworm Eisenia fetida using the biomarker response index

Thallium (Tl), though not essential for biological systems, is widely used in industrial activities, resulting in soil pollution and adverse effects on soil biota. Systematic toxicological studies on Tl, especially concerning soil organisms, are relatively rare. This research evaluates the toxic effects of Tl on earthworms by measuring oxidative stress biomarkers, such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG), and by assessing the expression of functional genes, such as heat shock protein 70 (Hsp70), metallothionein (MT), and annetocin (ANN). Additionally, this study employs the Biomarker Response Index (BRI) and two-way ANOVA to comprehensively assess the cumulative toxicity of Tl in earthworms. The findings indicate that Tl exposure significantly exacerbates oxidative stress and cellular damage in earthworms, particularly under conditions of high concentration and prolonged exposure. BRI results demonstrate a continuous decline in the physiological state of earthworms with increasing Tl concentration and exposure duration. Two-way ANOVA reveals significant dose-responsive increases in SOD and CAT activities, as well as in ANN gene expression. Apart from GST activity, other biomarkers significantly increased over time, and the changes in biomarkers such as SOD, CAT, MDA, and 8-OHdG were significantly influenced by dose and time. LSD post hoc tests show significant effects of dose, time, and their interactions on all biomarkers except for GST. These findings are valuable for gaining a deeper understanding of the ecological risks of Tl in soil environments and its potential threats to soil biota, aiding in the management of ecological risks associated with Tl-contaminated soils.

Co-exposure of decabromodiphenyl ethane and cadmium increases toxicity to earthworms: Enrichment, oxidative stress, damage and molecular binding mechanisms

The increase of electronic waste worldwide has resulted in the exacerbation of combined decabromodiphenyl ethane (DBDPE) and cadmium (Cd) pollution in soil, posing a serious threat to the safety of soil organisms. However, whether combined exposure increases toxicity remains unclear. Therefore, this study primarily investigated the toxic effects of DBDPE and Cd on earthworms at the individual, tissue, and cellular levels under single and combined exposure. The results showed that the combined exposure significantly increased the enrichment of Cd in earthworms by 50.32-90.42 %. The toxicity to earthworms increased with co-exposure, primarily resulting in enhanced oxidative stress, inhibition of growth and reproduction, intensified intestinal and epidermal damage, and amplified coelomocyte apoptosis. PLS-PM analysis revealed a significant and direct relationship between the accumulation of target pollutants in earthworms and oxidative stress, damage, as well as growth and reproduction of earthworms. Furthermore, IBR analysis indicated that SOD and POD were sensitive biomarkers in earthworms. Molecular docking elucidated that DBDPE and Cd induced oxidative stress responses in earthworms through the alteration of the conformation of the two enzymes. This study enhances understanding of the mechanisms behind the toxicity of combined pollution and provides important insights for assessing e-waste contaminated soils.

Pesticides impacts on human health and the environment with their mechanisms of action and possible countermeasures

Pesticides are chemical constituents used to prevent or control pests, including insects, rodents, fungi, weeds, and other unwanted organisms. Despite their advantages in crop production and disease management, the use of pesticides poses significant hazards to the environment and public health. Pesticide elements have now perpetually entered our atmosphere and subsequently contaminated water, food, and soil, leading to health threats ranging from acute to chronic toxicities. Pesticides can cause acute toxicity if a high dose is inhaled, ingested, or comes into contact with the skin or eyes, while prolonged or recurrent exposure to pesticides leads to chronic toxicity. Pesticides produce different types of toxicity, for instance, neurotoxicity, mutagenicity, carcinogenicity, teratogenicity, and endocrine disruption. The toxicity of a pesticide formulation may depend on the specific active ingredient and the presence of synergistic or inert compounds that can enhance or modify its toxicity. Safety concerns are the need of the hour to control contemporary pesticide-induced health hazards. The effectiveness and implementation of the current legislature in providing ample protection for human health and the environment are key concerns. This review explored a comprehensive summary of pesticides regarding their updated impacts on human health and advanced safety concerns with legislation. Implementing regulations, proper training, and education can help mitigate the negative impacts of pesticide use and promote safer and more sustainable agricultural practices.

Soil health hazards of di(2-ethylhexyl) phthalate: New perspectives on earthworms from different ecological niches DNA damage, gut microbial disruption and soil enzyme changes

Di(2-ethylhexyl) phthalate (DEHP) is perceived an emerging threat to terrestrial ecosystem, however, clear and accurate studies to fully understander ecotoxicity and underlying mechanisms of DEHP on the soil fauna remain poorly understood. Therefore, this study conducted a microcosm experiment of two earthworm ecotypes to investigate the ecological hazards of DHEP from multiple perspectives. The results showed that DEHP significantly increased the 8-hydroxy-deoxyguanosine (8-OHdG) content both in Eisenia foetida (13.76-133.0%) and Metaphire guillelmi (11.01-49.12%), leading to intracellular DNA damage. Meanwhile, DEHP negatively affected the expression of functional genes (ATP-6, NADH1, COX), which may be detrimental to mitochondrial respiration and oxidative stress at the gene level. The two earthworm guts shared analogous dominant bacteria however, the incorporation of DEHP drastically suppressed the homogeneity and diversity of the gut microbes, which further disrupted the homeostasis of the gut microbial ecological network. The keystone species in the gut of E. foetida decreased under DEHP stress but increased in the gut of M. guillelmi. Moreover, DEHP presented detrimental effects on soil enzyme activity, which is mainly associated with pollutant levels and earthworm activity. Collectively, the findings expand the understanding of soil ecological health and reveal the underlying mechanisms of the potential exposure risk to DEHP.