Typically, nanoplastics (NPs) are contaminated before entering soil, and the impact of NPs on the biotoxicity of Persistent Organic Pollutants (POPs) they carry remains unclear. This study simulated two environmentally relevant scenarios: singular exposure of benzo[a]pyrene (BaP) in soil and exposure via NPs loading (NP-BaP). Correlation analysis and machine learning revealed that injury in earthworms exposed for 28 days was significantly associated with NPs. Moreover, when the soil exposure concentration of BaP was 4 mg/kg, the NP-BaP group exhibited 10.67 % greater pigmentation than the BaP-only group. Despite the lower biota soil accumulation factor (BSAF) of earthworms in the NP-BaP group, the concentration of BaP in the soil remained at higher levels in the late stages of exposure. This led to NP-BaP inducing a stronger trend of oxidative damage compared to BaP alone. Furthermore, molecular-level studies indicated that the differential preferences of NPs and BaP for damaging antioxidant enzymes were linked to individual oxidative stress responses. This study confirmed that NPs, at non-toxic concentrations, could increase the persistence of BaP's biological toxicity after prolonged exposure, highlighting the potential safety risks of NPs as carriers of POPs to soil organisms.

As a class of emerging persistent organic pollutants (POPs), per- and polyfluoroalkyl substances (PFASs) are widely detected in the soil environment, posing a significant threat to the soil ecosystem and human health. Therefore, it is necessary to study the ecotoxicological effects of PFASs in soil. In this study, we conducted a comprehensive review of the toxic effects of PFASs on earthworms at the individual and sub-individual levels, including survival status, body weight, reproduction, oxidative damage, genes, metabolism, and so on. Results showed that earthworms exposed to certain concentrations of PFASs display various pathological symptoms on their body surfaces, a decrease in body weight and reproductive rate, and even death. The LC50 values of PFOS to earthworms (365-1404 mg/kg) are consistently lower than those of PFOA (544-1307 mg/kg) under the same exposure condition, indicating a higher toxicity of PFOS compared to PFOA. At the sub-individual level, PFASs may induce oxidative stress, DNA damage, aberrant gene expression, and metabolic disruption in earthworms. PFOS induced disruption of the nervous and metabolic system, PFHxS disrupted energy balance and elicited inflammation, and PFBS induced cell apoptosis in earthworms. Compared to PFOS, PFHxS may induce a greater degree of oxidative stress and damage, and 6:2 Cl-PFESA (F-53B) exhibited a greater propensity to disrupt the extracellular matrix and induce cellular ferroptosis and apoptosis in earthworms. At environmentally relevant concentration levels, PFOA induces significant dysregulation of pathways related to amino acid, energy, and sulfur metabolisms within earthworms. Bioavailability and bioaccumulation capacity of PFASs are important factors in determining their toxicological effects in soil, which is influenced by the molecular structure of PFASs and the combined effects of various environmental factors, such as soil organic matter composition and content, pH, PFAS concentrations and exposure duration. Finally, existing research deficiencies and future directions about the toxicological research of PFASs on earthworms are proposed, aiming to offer reference for ecological risk assessment of PFASs-contaminated soil.

Soil is an important sink for microplastics (MPs) and pesticides. MPs can act as carriers for pesticides, thus induce direct and indirect effects on soil organisms. Fluindapyr (FIP), a novel succinate dehydrogenase inhibitors fungicides (SDHIs), may pose a serious threat to earthworms. However, few studies have evaluated the effects of joint exposure to MPs and FIP. Here, earthworms (Eisenia fetida) were jointly exposed to PMMA (polymethylmethacrylate) and PS (polystyrene) MPs of different sizes (0.1, 1 and 10 mu m) along with FIP for 28-day to investigate the toxic effects of single and joint exposure of FIP and MPs on earthworms. The results showed that joint exposure to 0.1 and 1 mu m MP promoted the accumulation of FIP in earthworms at the beginning of the experiment compared to the sole group, but the elimination of FIP from earthworms accelerated after 14 d. In addition, the joint exposure caused more serious damages to the epidermis and intestine of earthworms and increased the severity of oxidative stress. The effects of joint exposure to FIP and MPs depended on the size of the MPs, and the strongest effects were observed in the treatment with the smallest size. The 16S rRNA sequencing results showed that the joint exposure to MPs and FIP didn't cause gut microbiota dysbiosis. However, the sole 0.1 mu m PS significantly altered the community diversity and richness of earthworm gut bacteria, and the relative abundance of Proteobacteria, Actinobacteria and Firmicutes was significantly changed. The obtained results inferred that MPs could influence environmental and toxicological behaviors of FIP and may provide data support for the risk assessments of MPs and FIP on soil ecosystems.

The high global production combined with low recycling rates of polystyrene (PS) and low-density polyethylene (LDPE) contributes to the abundance of these commonly used plastics in soil, including as microplastics (MPs). However, the combined effects of MPs and heavy metals, such as arsenic (As) on earthworms are poorly understood. Here, we show that neither PS nor LDPE altered the effects of As on the survival, growth, and reproduction of the earthworm Eisenia fetida. As stress, both alone and in combination with the MPs, induced DNA damage in coelomocytes. In As-exposed earthworms, PS and LDPE increased the accumulation of reactive oxygen species while the activities of the antioxidant enzymes peroxidase, superoxide dismutase, and catalase were significantly lower under combined PS/LDPE + As exposure than under As exposure alone. As stress alone reduced cocoon production and the mRNA level of the reproduction-related gene ANN whereas As combined with PS/LDPE reduced the mRNA levels of CYP450, an enzyme involved in detoxification. Integrated biomarker response analysis revealed that PS/LDPE did not significantly impact the overall ecotoxicological effects of As exposure on earthworms. This study provides important insights into the potential ecological risks of MPs in heavy-metal-contaminated soil.

The present study aimed to i) assess the disintegration of a novel bio-packaging during aerobic composting (2 and 6 % tested concentrations) and evaluate the resulting compost ii) analyse the ecotoxicity of bioplastics residues on earthworms; iii) study the microbial communities during composting and in 'earthworms' gut after their exposure to bioplastic residues; iv) correlate gut microbiota with ecotoxicity analyses; v) evaluate the chemicophysical characterisation of bio-packaging after composting and earthworms' exposure. Both tested concentrations showed disintegration of bio-packaging close to 90 % from the first sampling time, and compost chemical analyses identified its maturity and stability at the end of the process. Ecotoxicological assessments were then conducted on Eisenia fetida regarding fertility, growth, genotoxic damage, and impacts on the gut microbiome. The bioplastic residues did not influence the earthworms' fertility, but DNA damages were measured at the highest bioplastic dose tested. Furthermore bioplastic residues did not significantly affect the bacterial community during composting, but compost treated with 2 % bio-packaging exhibited greater variability in the fungal communities, including Mortierella, , Mucor, , and Alternaria genera, which can use bioplastics as a carbon source. Moreover, bioplastic residues influenced gut bacterial communities, with Paenibacillus, , Bacillus, , Rhizobium, , Legionella, , and Saccharimonadales genera being particularly abundant at 2 % bioplastic concentration. Higher concentrations affected microbial composition by favouring different genera such as Pseudomonas, , Ureibacillus, , and Streptococcus. . For fungal communities, Pestalotiopsis sp. was found predominantly in earthworms exposed to 2 % bioplastic residues and is potentially linked to its role as a microplastics degrader. After composting, Attenuated Total Reflection analysis on bioplastic residues displayed evidence of ageing with the formation of hydroxyl groups and amidic groups after earthworm exposure.

Global water scarcity entailed the use of treated wastewater (TWW) in agriculture, however, this water can vehiculate numerous pollutants into soil and further crops such as microplastics (MPs). To date, few studies had quantified the accumulation of MPs in soils and earthworms after irrigation with TWW as well as their toxicological effects. Hence, the main objective of the present work is to evaluate the toxicity of MPs using Lumbricus sp. earthworms collected from TWW irrigated soils with an increasing gradient of time (5 years, 16 years and 24 years). MPs determination in soil, as well as in earthworms were performed. The intestinal mucus was quantified, and cytotoxicity (Lysosomal membrane stability (LMS), Catalase (CAT) and glutathione-S-Transferase (GST) activities), neurotoxicity (Acetylcholinesterase activity (AChE)) and genotoxicity (Micronuclei frequency (MNi)) biomarker were assessed. Our results revealed that the use of TWW rendered MPs accumulation in earthworms' tissues and induce alteration on the intestinal mucus. An important cytotoxicity time-depending was observed being associated with an increase on genotoxicity. Overall, the present investigation highlights the ecotoxicological risk associated with the use of TWWs as an important driver of MPs and consequently measures are necessary to reduce MPs in wastewater treatment plans to improve this non-conventional water quality.

Many studies have reported the toxic effects of microplastics (MPs) on organisms, especially on how conventional plastics affect organisms after short-term exposure. The effects of biodegradable plastics on organisms are, however, largely unexplored, especially concerning their impact after long-term exposure. We perform a series of experiments to examine the effects of conventional (polyethylene (PE)) and biodegradable (polylactic acid (PLA)) microplastics on earthworms at three concentrations (0.5 %, 2 %, and 5 % (w/w)) and particle sizes (149, 28, and 13 mu m) over short- (14 d) and long-term (28 d) periods of exposure. Negative effects on earthworms are more pronounced following exposure to PE than PLA, particularly over the shorter term. After longerterm exposure, earthworms may adapt to PE and PLA environments. A close relationship exists between the effects of MPs on earthworms and activities of superoxide dismutase, catalase, and malondialdehyde enzymes, which we use to evaluate the degree of antioxidant damage. We report both PE and PLA to negatively affect earthworms, but for the effects of PLA to be less severe after longer-term exposure. Further investigation is required to more fully assess the potential negative effects of PLA use on soil organisms in agriculture.

The escalating utilization of carbon dots (CDs) in agriculture raises ecological concerns. However, their combined toxicity with arsenic remains poorly understood. Herein, we investigated the combined mitochondrial genotoxicity of CDs and arsenate at environmentally relevant concentrations across successive earthworm generations. Iron-doped CDs (CDs(-Fe)) strongly bound to arsenate and arsenite, while nitrogen-doped CDs (CDs(-N)) exhibited weaker binding. Both CDs enhanced arsenate bioaccumulation without affecting its biotransformation, with most arsenate being reduced to arsenite. CDs(-Fe) generated significantly more reactive oxygen species than did CDs-N, causing stronger mitochondrial DNA (mtDNA) damage. Arsenate further exacerbated the oxidative mtDNA damage induced by CDs(-N), as evidenced by increased reactive oxygen species, elevated 8-oxo-7,8-dihydro-2 '-deoxyguanosine (8-OHdG) levels, and a higher correlation between 8-OHdG and mtDNA damage. This was due to arsenic inhibiting the antioxidant enzyme catalase. This exacerbation was negligible with CDs(-Fe) because their strong binding with arsenic prevented catalase inhibition. Maternal mitochondrial DNA damage was inherited by filial earthworms, which experienced significant weight loss in coexposure groups coupled with mtDNA toxicity. This study reveals the synergistic genotoxicity of CDs and arsenate, suggesting that CDs could disrupt the arsenic biogeochemical cycle, increase arsenate risk to terrestrial animals, and influence ecosystem stability and health through multigenerational impacts.

To assess the ecological risk of microplastics (MPs) in agricultural systems, it is critical to simultaneously focus on MP-mediated single-organism response and different trophic-level organism interaction. Herein, we placed earthworms in soils contaminated with different concentrations (0.02% and 0.2% w/w) of polyethylene (PE) and polypropylene (PP) MPs to investigate the effect of earthworms on tomato against Helicoverpa armigera (H. armigera) under MPs stress. We found that earthworms alleviated the inhibitory effects of MPs stress on tomato growth and disrupted H. armigera growth. Compared to individual MPs exposure, earthworm incorporation significantly increased the silicon and lignin content in herbivore-damaged tomato leaves by 19.1% and 57.6%, respectively. Metabolites involved in chemical defense (chlorogenic acid) and phytohormones (jasmonic acid) were also activated by earthworm incorporation. Furthermore, earthworms effectively reduced oxidative damage induced by H. armigera via promoting antioxidant metabolism. Overall, our results suggest that utilizing earthworms to regulate above- and below-ground interactions could be a promising strategy for promoting green agriculture.

The chiral fungicide prothioconazole (PTZ) is extensively employed in agricultural practices, prompting serious concern due to its environmental impact. PTZ is prone to undergo metabolism, leading to the formation of chiral prothioconazole-desthio (dPTZ) in the environment. However, limited knowledge exists regarding its enantioselective behavior and toxicity towards invertebrate organisms in soil ecosystems. In this study, R -(-)- and S -(+)- PTZ enantiomers were individually synthesized, and their stereoselective toxicity effects on earthworms ( E. foetida ) were studied in artificial soil under environmentally relevant concentration exposures. The results showed a significant accumulation of dPTZ in earthworms, surpassing the levels of PTZ. Moreover, the concentration of S -(-)- dPTZ in earthworms was notably higher than that of R -(+)- dPTZ after exposure, reaching peak levels on day 14. Concurrently, oxidative stress induced by S -(+)- PTZ enantiomers in earthworms exhibited a substantial increase compared to R -(-)- enantiomers on day 14, indicating a higher ecological risk associated with the former in non -target organisms. Transcriptome analysis unveiled distinct impacts on earthworm physiology. S -(+)-PTZ exposure significantly affected energy metabolism, immune responses and digestive systems. In contrast, R -(-)-PTZ exposure influenced the synthesis of carbohydrates, proteins, and lipids. These insights contribute to understanding the complex interactions between PTZ enantiomers and soil -dwelling organisms, providing a scientific foundation for advancing the application of high efficiency, low toxicity PTZ monomer pesticides.