Species-specific benefits in bioremediation of oil refinery sludge via large-scale vermicomposting process: a detailed comparison between Eisenia fetida and Eudrilus eugeniae.

Co-exposure to decabromodiphenyl ethane and cadmium disrupts gut homeostasis in earthworms (Eisenia fetida): Insights from microbiome-metabolome analysis

The expanding insect farming industry generates up to 67,000 tons of frass per year. Its potential use as fertilizer is promising, but has not yet been widely studied. This study aimed to characterize the chemical composition, organic matter structure, ecotoxicity, and phytotoxicity of frass from four insect species in order to evaluate its potential as a fertilizer. We compared four types of insect frass (IF) (Tenebrio molitor, Galleria mellonella, Hermetia illucens, and Acheta domesticus) to Eisenia fetida vermicompost (EFV). We used physicochemical analyses (pH, electrical conductivity (EC), macro-micronutrients and dissolved organic carbon (DOC), spectroscopy (solid-state 13C nuclear magnetic resonance (NMR), and Fourier-transform infrared spectroscopy (FTIR)) and thermogravimetry/differential scanning calorimetry (TGA/DSC: R1, R2, Tmax), together with phytotoxicity (germination index, %GI) and ecotoxicity (toxicity units, TU) bioassays. Composition was species-dependent: A. domesticus showed the highest levels of nitrogen (N), phosphorus (P), and potassium (K); the concentration of DOC was higher in insect frass (IF) than in EFV, with the highest concentration found in IF of T. molitor. 13C NMR/FTIR profiles distinguished between frass (carbohydrates/proteins and chitin signals) and EFV (humified, oxidized matrix). Thermal stability followed: G. mellonella (R1 ≈ 0.88) ≥ A. domesticus (0.79) > H. illucens (0.73) > EFV (0.67) > T. molitor (0.50). In bioassays, T. molitor and A. domesticus exhibited phytotoxicity (%GI < 30), whereas G. mellonella and H. illucens did not. EFV exhibited the highest %GI. Dilution increased %GI in all materials, especially in T. molitor and A. domesticus, and reduced acute risk (TU). Frass is not a uniform input: its agronomic performance emerges from the interaction between EC (ionic stress), the availability of labile C (DOC, C/N and low-temperature exotherms), and structural stability (R1/R2 and aromaticity). In terms of formulation, IF can provide nutrients that mineralize rapidly, whereas EFV contributes stability. Controlling the inclusion and dilution of materials (e.g., limiting the amount of T. molitor in blends) and considering the mixing matrix helps to manage phytotoxicity and ecotoxicity, and realize the fertilizer value of the product.

Ecotoxicological effects of soil microplastic types and concentrations on earthworms.

Pretilachlor (PR), a pre-emergence herbicide crucial for rice weed management, is prone to rapid degradation and poses significant environmental risks, necessitating frequent applications. This study aims to develop an environmentally friendly carboxymethyl chitosan (CMCS)/Cu2+ hydrogel delivery system that provides controlled release, enhances application efficacy, and mitigates ecological impacts while utilizing biowaste-derived materials. CMCS hydrogel particles crosslinked via Cu2+ coordination achieved a PR loading capacity (LC) of 13.70 ± 0.32%. The system displayed pH-responsive behavior with maximum swelling (429%) at pH 8, enabling sustained PR release (51.2% over 80 h) and rapid biodegradation (83.9% mass loss within 7 days). At an agronomically relevant dosage of 500 g a.i. (active ingredient) ha-1, the hydrogel formulation provided effective Echinochloa crus-galli control comparable to commercial standards while eliminating rice phytotoxicity. Ecotoxicity assessments revealed significantly reduced environmental risks, with LC50 values of 0.60 mg L-1 for Danio rerio (1.7-fold safer than emulsifiable concentrate (EC)) and >1600 mg kg-1 for Eisenia fetida. This study demonstrates the feasibility of utilizing CMCS/Cu2+ hydrogel particles as a controlled-release delivery system for PR in rice cultivation. The developed formulation provides sustained herbicide release aligned with early weed growth stages, reduced non-target toxicity, and enhanced biodegradability compared to conventional formulations. While further field validation is needed, this approach offers a promising foundation for developing more environmentally compatible pesticide delivery systems that could potentially reduce application frequency and environmental loading in rice production. © 2026 Society of Chemical Industry.

Assessing the toxicity of environmentally-relevant pesticide mixtures on earthworms, Eisenia fetida and Lumbricus rubellus in European and Argentine cropping systems.

Silver nanoparticles (AgNPs) are increasingly applied in agriculture and related technologies due to their antimicrobial properties, yet their interactions with soil-associated organisms and microbial communities remain insufficiently characterized. This study examined the effects of AgNP exposure (10.85 mg/L) on trace element accumulation and gut bacterial communities of the earthworm Eisenia fetida under two substrate conditions (horticultural substrate and compost). High-throughput 16S rRNA gene sequencing revealed substrate-dependent shifts in microbial community structure following AgNP exposure. Several bacterial taxa, including Proteobacteria, Gammaproteobacteria, Bacilli, Streptococcus sp., and Staphylococcus sp., exhibited pronounced numerical declines, indicating sensitivity to AgNPs, whereas Actinobacteria and Bacteroidetes showed comparatively higher relative abundances, suggesting greater tolerance. Compost partially mitigated the inhibitory effects of AgNPs on gut microbiota. Concurrently, AgNP exposure altered trace element accumulation patterns in earthworm tissues, highlighting interactions between silver uptake and elemental homeostasis. Collectively, these findings demonstrate that AgNPs can induce taxon- and substrate-specific responses in earthworm-associated microbial communities and metal accumulation, providing insight into potential ecological consequences of nanoparticle use in agricultural systems.

Microplastic pollution in annelids: A systematic review of species-specific impacts, toxicity pathways, and ecological risks.

Soil health is supported by diverse communities of organisms, including springtails and earthworms, facilitating essential processes such as nutrient cycling, organic matter decomposition, and soil structure maintenance. Cultural control methods promoted through Integrated Pest Management (IPM) are often assumed to be environmentally friendly, and their potential effects on soil health have received limited attention. Biofumigation, a cultural tactic, utilizes cruciferous plants like Brassica juncea (Brassicales: Brassicaceae), or their byproducts, to control soil-borne pests, yet their impacts on non-target organisms remain understudied. In this greenhouse study, we evaluated the impact of soil biofumigation with brown mustard seed meal (BMSM) on the springtail Folsomia candida (Entomobryomorpha: Isotomidae) and the earthworm Eisenia fetida (Opisthopora: Lumbricidae). An 85% reduction in springtail populations was recorded within 1 h of BMSM application. However, the springtail population recovered and surpassed the number of springtails in untreated media after 26 days. Earthworms preferred untreated media over BMSM-treated media immediately after incorporation. However, earthworms reared in the biofumigated media had higher body weight and produced more viable cocoons compared to those reared in untreated media. The negative effects of biofumigation on springtails and the deterrence of earthworms appeared to be short-lived and may later contribute to their reproductive fitness.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-33634-y.

Assessing metal bioconcentration in terrestrial organisms is essential for understanding the ecotoxicological risks associated with soil contamination. This study investigates the potential of portable x-ray fluorescence spectrometry (pXRF) as a rapid, non-destructive method for quantifying metal and metalloid bioconcentration in the compost worm Eisenia fetida following exposure to contaminated soils. Initial calibration was performed using spiked worms to establish the relationship between internal concentrations and pXRF signal response. Subsequently, E. fetida individuals were exposed to 48 contaminated soils with varying contamination profiles. After a controlled exposure period, metal and metalloid concentrations in the worms' tissues were measured using a pXRF spectrometer and inductively coupled plasma spectrometer. The results obtained by pXRF were original and demonstrate some significant relationships by comparison with internal concentrations measured with conventional elemental analysis methods. By incorporating a modeling step, the predictive capabilities of pXRF data were further validated. The findings highlight the applicability of pXRF for monitoring of metal bioconcentration in soil invertebrates, aligning with the principles of green analytical chemistry by minimizing sample destruction, analysis time, and cost. This approach offers a promising alternative to traditional laboratory methods and could significantly enhance environmental risk assessment and biomonitoring strategies for contaminated sites.

Ecotoxicological Assessment of Thiamethoxam on the Behavior and Population Dynamics of Eisenia fetida

Metabolomics insights into the combined effects of boscalid and polystyrene microplastics on earthworms (Eisenia fetida): The critical role of pesticide dose and microplastics size.

UV-aged nanoplastics induced stronger biotoxicity to earthworms: Differential effects and the underlying mechanisms of pristine and aged polystyrene nanoplastics.

Transgenerational effects of silver nanoparticles in soil to earthworms (Eisenia fetida)

Ecotoxicological effects of fluensulfone on non-target soil organisms: Phenotypic and molecular toxicity responses in Eisenia fetida.

Therapeutic effects of G90'-ES2 protein complex from regenerated Eisenia fetida on radiation-induced skin injury.

Diclofenac (DCF), a broad-spectrum anti-inflammatory drug, has serious ecological implications, particularly in driving South Asian vulture population declines. We isolate Serratia sp. strain EWG9 from the gut of the compost worm Eisenia fetida as a fast degrader of DCF. Strain EWG9 mineralized 0.125 g/l diclofenac completely in 24 h, by far outcompeting earlier reported degraders. Whole-genome sequencing identified protocatechuate 3,4-dioxygenase and enzymes of the β-ketoadipate pathway genes. Protein–Protein Interaction (PPI) analysis also emphasized major regulatory and metabolic nodes coordinating diclofenac catabolism. These results situate strain EWG9 as a potential candidate for pharmaceutical bioremediation and represent the first description of a worm-gut bacterium with complete diclofenac degradation activity.

Locally available materials could be used to address soil fertility constraints. Vermicomposting is a promising technology where various organic materials are converted into processed compost by earthworms. This study was conducted at the Haro sabu Agricultural Research Center on-station during the consecutive two years (2021 - 2022 years) with the aim to evaluate the quality of vermicompost made from different locally available waste materials to explore the possibility of using organic fertilizers for sustainable agriculture and minimize the use of chemical fertilizers in the crop production and reduce soil pollution. The experiment consisted of ten different treatments in the ratio of 1:1 cattle manure to crop residues on a weight basis viz., T1: Cow manure + maize straw, T2: Cow manure + haricot bean straw, T3: Cow manure + coffee husk/pulp, T4: Cow manure + green leaf, T5: Cow manure + haricot bean straw + maize straw, T6: Cow manure + coffee husk/pulp + maize straw, T7: Cow manure + green leaf + maize straw, T8: Cow manure + haricot bean straw + coffee husk/pulp, T9: Cow manure + haricot bean straw + green leaf, and T10: Cow manure + maize straw + haricot bean straw + coffee husk/pulp + green leaf. Water was sprayed to maintain optimum moisture for worms as it needed. The substrates were chopped and added to the worm bin. A red worm (Eisenia fetida) was used for the preparation of vermicompost. Matured composite vermicompost samples were prepared and collected for laboratory analysis. The laboratory result showed that the pH values of all feeding substrates are found in a suitable range for the survival of earthworms and also for plant growth. The OC, TN, available P, C:N ratio, and CEC of vermicompost made from all material were excellent and promise improvement of soil properties. The highest value of available P and K was also registered from vermicompost prepared from all materials. Even if the values of recorded nutrients were different, the vermicompost obtained from all substrates was rich in selected micronutrients. Therefore, the nutrient content of vermicompost prepared from all substrates showed the highest values for all selected micro plant nutrients. Thus, the vermicompost made from all materials could correct the plant nutrient imbalance and could be used for vermicompost preparation based on the accessibility of materials. Also utilizing the vermicompost for crop production and enhancing soil fertility.

Vermicomposting is a sustainable bioconversion process in which earthworms transform organic residues into nutrient-rich bio fertilizers under mesophilic conditions, with pH and moisture critically influencing decomposition efficiency. While microbial activity initiates substrate breakdown, Eisenia fetida plays a central role in stabilizing organic matter and enhancing nutrient content. This study investigated the performance of E. fetida in the 60-day vermicomposting of three locally available biodegradable wastes coffee husk, paper waste, and vegetable residues in Dambi Dollo town,at Dambi Dollo University Research center, Ethiopia. Coffee husk and paper waste were mixed with cow dung (3:1 ratio), whereas vegetable residues were composted without cow dung. Thirty mature worms were introduced per treatment, and samples were analyzed at Days 0, 30, and 60 for physicochemical and biological parameters. The results revealed significant transformations in substrate quality, including pH (7.51-7.03), EC (1.91-1.24 mS/cm), organic matter (47.06-29.21%), organic carbon (27.3-16.93%), total nitrogen (1.38-2.19%), C: N ratio (21.39-8.63), available phosphorus (11.17-20.85ppm), and exchangeable potassium (2.26-4.43mg/kg). The final vermicompost was well-stabilized, nutritionally enriched, and compliant with WHO and ISIRI standards. This study demonstrates the potential of vermicomposting as a cost-effective, environmentally sustainable, and locally adaptable solution for managing biodegradable waste, providing high-quality organic fertilizers for agricultural use. These findings offer insights applicable to similar tropical and subtropical African regions, emphasizing the role of vermiculture in promoting circular economy and sustainable agriculture.

Chemical fertilizers have increased agricultural yields and fed thousands of people for over 60 years. Synthetic additives (Urea and diammonium phosphate) increase yield but also increase soil contamination, residual chemical bioaccumulation, and impacts on soil fauna. Additionally, earthworms and other soil-dwelling microorganisms are at risk due to the use of chemical fertilizers. Urea and diammonium phosphate are commonly used fertilizers for cash crops (wheat, rice, maize, and soyabean) in managed agro-ecosystems. The present experiment aimed to study the impact of using chemical fertilizers in agricultural practices on soil-inhabiting earthworms, Eisenia fetida and the imposition of significant risks to farmers' friends. The present study was designed to raise earthworms, E. fetida, in laboratory conditions according to OECD guidelines (1984) number 207, using artificial soil treated with a binary combination mixture of urea and DAP (LC10Urea+LC10DAP) for 60 days. Results showed that the presence of chemical fertilizers (LC10Urea+LC10DAP-a binary mixture) in the treatment exerted a sublethal toxicological effect on earthworms' E. fetida capacity for biomass accumulation. On days 15 and 60, histological observation were also noted in the body wall of the earthworm, E. fetida. The number of galandular cells in the epithelial layer increases on day 15 to 60. On day 60 of E. fetida treatment group, a slight rupture in the epithelial layer is observed. The present study demonstrated that the detrimental effects of nitrogenous fertilizers on earthworms can have significant ecological repercussions for the entire terrestrial ecosystem, in addition to harming important soil fauna.