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Earthworms can resist high levels of soil copper (Cu) contamination and play an essential role in absorbing them effectively. However, the molecular mechanisms underlying Cu tolerance in earthworms are poorly understood. To address this research gap, we studied alterations of Eisenia fetida in antioxidant enzymes, gut microbiota, metabolites, and genes under varying levels of Cu exposure soils (0, 67.58, 168.96, 337.92 mg/kg). Our results revealed a reduction in antioxidant enzyme activities across all treatment groups, indicating an adaptive response to alleviate Cu-induced oxidative stress. Analysis of gut microbiota revealed a significant increase in the abundance of bacteria associated with nutrient uptake and Cu2+ excretion under Cu stress. Furthermore, metabolomic analysis discovered an increase in certain metabolites associated with energy metabolism, such as pyruvic acid, L-malic acid, and fumaric acid, as Cu concentration escalated. These results suggested that enhanced energy supply contributes to the elevated tolerance of E. fetida towards Cu. Additionally, transcriptome analysis not only identified crucial detoxification genes (Hsp70 , CTSL , GST , CHAC , and GCLC), but also confirmed the critical role of glutathione metabolism as a key pathway in E. fetida Cu detoxification processes. These findings provide a new perspective on the molecular mechanisms of Cu tolerance in earthworms. [Display omitted] • The multi-omics of E. fetida under Cu stress were determined. • Antioxidant enzyme system in E. fetida responded to Cu stress. • Increased energy supply helps improve tolerance of E. fetida towards Cu. • Glutathione metabolic pathway play important roles in Cu detoxification. [ABSTRACT FROM AUTHOR]

Farmland soil organisms frequently encounter pesticide mixtures presented in their living environment. However, the underlying toxic mechanisms employed by soil animals to cope with such combined pollution have yet to be explored. This investigation aimed to reveal the changes in cellular and mRNA levels under chlorpyrifos (CPF) and lambda -cyhalothrin (LCT) co-exposures in earthworms (Eisenia fetida). Results exhibited that the combination of CPF and LCT triggered an acute synergistic influence on the animals. Most exposures resulted in significant alterations in the activities of total superoxide dismutase (T-SOD), copper/zinc superoxide dismutase (Cu/Zn-SOD), caspase 3, and carboxylesterase (CarE) compared to the basal level. Moreover, when exposed to chemical mixtures, the transcription levels of four genes [heat shock protein 70 (hsp70), gst , sod , and calreticulin (crt)] also displayed more pronounced changes compared with their individual exposures. These changes in determined parameters indicated the occurrence of oxidative stress, cell death, detoxification dysfunction, and endoplasmic reticulum damage after co-exposure to CPF and LCT in E. fetida. The comprehensive examination of mixture toxicities of CPF and LCT at different endpoints would help to understand the overall toxicity they cause to soil invertebrates. The augmented deleterious effect of these pesticides in a mixture suggested that mixture toxicity assessment was necessary for the safety evaluation and application of pesticide mixtures. [Display omitted] • Lambda -cyhalothrin held a lower acute effect on the earthworms than chlorpyrifos. • Co-exposure of chlorpyrifos and lambda -cyhalothrin triggered synergistic toxicity. • Activity of caspase3 was significantly inhibited in the co-exposure of pesticides. • Hsp70 was a potential biomarker for chlorpyrifos mixed with lambda -cyhalothrin. [ABSTRACT FROM AUTHOR]

This study explored the uptake of lead in the epigeic earthworm Dendrobaena veneta exposed to 0, 1000, and 2500 μg Pb/g soil. The soil metal content was extracted using strong acid digestion and water leaching, and analysed by means of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to estimate absolute and bioavailable concentrations of metals in the soil. The guts and heads of lead-exposed earthworms were processed into formalin-fixed and paraffin embedded sections for high-resolution multi-element metallomic imaging via Laser Ablation ICP-MS (LA-ICP-MS). Metallomic maps of phosphorus, zinc, and lead were produced at 15-μm resolution in the head and gut of D. veneta. Additional 4-μm resolution metallomic maps of the earthworm brains were taken, revealing the detailed localisation of metals in the brain. The Pb bioaccumulated in the chloragogenous tissues of the earthworm in a dose-dependent manner, making it possible to track the extent of soil contamination. The bioaccumulation of P and Zn in earthworm tissues was independent of Pb exposure concentration. This approach demonstrates the utility of LA-ICP-MS as a powerful approach for ecotoxicology and environmental risk assessments. • Lead exposure of earthworms causes a dose-dependent accumulation of Pb in the chloragog. • The distribution of P and Zn in earthworm tissues is independent of Pb exposure dose. • Metallomic LA-ICP-MS imaging promises to be a valuable tool for unravelling the detoxification mechanisms in soil invertebrates. [ABSTRACT FROM AUTHOR]

Afidopyropen has high activity against pests. However, it poses potential risks to the soil ecology after entering the environment. The toxicity of afidopyropen to earthworms (Eisenia fetida) was studied for the first time in this study. The results showed that afidopyropen had low level of acute toxicity to E. fetida. Under the stimulation of chronic toxicity, the increase of reactive oxygen species (ROS) level activated the antioxidant and detoxification system, which led to the increase of superoxide dismutase (SOD) and glutathione S-transferase (GST) activities. Lipid peroxidation and DNA damage were characterized by the increase of malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) contents. Meanwhile, the functional genes SOD , CAT , GST , heat shock protein 70 (HSP70), transcriptionally controlled tumor protein (TCTP), and annetocin (ANN) played a synergistic role in antioxidant defense. However, the comprehensive toxicity of high concentration still increased on the 28th day. In addition, strong histopathological damage in the body wall and intestine was observed, accompanied by weight loss, which indicated that afidopyropen inhibited the growth of E. fetida. The molecular docking revealed that afidopyrene combined with the surface structure of SOD and GST proteins, which made SOD and GST become sensitive biomarkers reflecting the toxicity of afidopyropen to E. fetida. Summing up, afidopyropen destroys the homeostasis of E. fetida through chronic toxic. These results provide theoretical data for evaluating the environmental risk of afidopyropen to soil ecosystem. [Display omitted] • Afidopyropen showed low toxicity to earthworm. • Afidopyropen destroys the homeostasis of earthworm through chronic toxic. • Afidopyropen changes the structure of SOD and CAT proteins in earthworm. [ABSTRACT FROM AUTHOR]

The chiral pesticide hexythiazox was extensively employed in agricultural activities and has garnered growing concern for its harmful impact on the ecosystem. This study investigates the toxicodynamic earthworm at the enantiomeric level of hexythiazox. Earthworms exhibited notable enantioselectivity during the accumulation stage. Furthermore, the presence of earthworms can impact the rate of degradation and enantioselectivity of hexythiazox in soil. The accumulation of the two hexythiazox enantiomers in the earthworm adhered to the one-compartment model, whereas the elimination phase was governed by the first-order kinetics equation. Furthermore, it was discovered that there was no notable enantioselectivity observed during the elimination phase. [Display omitted] • Hexythiazox bioaccumulation in earthworms reached its highest point on day 7. • (+)-Hexythiazox was preferentially enriched in earthworms during the accumulation phase. • Earthworms accelerate the degradation and enhance degradation enantioselectivity of hexythiazox in soils. • No significant enantioselectivity was observed in earthworms during the elimination phase. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, an abundance of plastic face masks has been consumed and disposed of in the environment. In addition, substantial amounts of plastic mulch film have been used in intensive agriculture with low recovery. Butyl benzyl phthalate (BBP) and TiO 2 nanomaterials (nTiO 2) are widely applied in plastic products, leading to the inevitable release of BBP and nTiO 2 into the soil system. However, the impact of co-exposure of BBP and nTiO 2 at low concentrations on earthworms remains understudied. In the present study, transcriptomics was applied to reveal the effects of individual BBP and nTiO 2 exposures at a concentration of 1 mg kg−1, along with the combined exposure of BBP and nTiO 2 (1 mg kg−1 BBP + 1 mg kg−1 nTiO 2 (anatase)) on Metaphire guillelmi. The result showed that BBP and nTiO 2 exposures have the potential to induce neurodegeneration through glutamate accumulation, tau protein, and oxidative stress in the endoplasmic reticulum and mitochondria, as well as metabolism dysfunction. The present study contributes to our understanding of the toxic mechanisms of emerging contaminants at environmentally relevant levels and prompts consideration of the management of BBP and nTiO 2 within the soil ecosystems. [Display omitted] • Co-exposure to BBP and nTiO 2 caused neuronal damage in Metaphire guillelmi. • Co-exposure of BBP and nTiO 2 caused metabolic dysfunction in Metaphire guillelmi. • BBP and nTiO 2 affected Metaphire guillelmi at environmental-relevant concentrations. [ABSTRACT FROM AUTHOR]

Here, the complete mitochondrial genome (mitogenome) of Drawida gisti was sequenced and compared with the mitogenomes of other Metagynophora species. The circular mitogenome was 14,648 bp in length and contained two ribosomal RNA genes (rRNAs), 13 protein-coding genes (PCGs), and 22 transfer RNA genes (tRNAs). The types of constitutive genes and the direction of the coding strand that appeared in Drawida mitogenome were identical to those observed in other Metagynophora species, except for a missing lengthy non-coding region. The conservative relationships between Drawida species were supported by the overall analyses of 13 PCGs, two rRNAs, and 22 tRNAs. A comparison of the Metagynophora mitogenomes revealed that the ATP8 gene possessed the highest polymorphism among the 13 PCGs and two rRNAs. Phylogenetic analysis suggested that the Moniligastridae contained Drawida , which is a primitive Metagynophora group. Our study provides a step forward toward elucidating the evolutionary linkages within Drawida and even Metagynophora. • Extremely small mitogenome size of Drawida gisti • Absence of lengthy non-coding regions in Drawida mitogenomes • Significant difference in codon usage of mitochondrial genes between Drawida and other earthworms • Conservative relationships of Metagynophora supported by mitogenomes [ABSTRACT FROM AUTHOR]

To investigate whether earthworm cellulases contribute to the innate immune system, the responsiveness of cellulase activity and mRNA expression to bacterial challenge was examined by zymography and RNA sequencing. A zymographic analysis revealed that the activity levels of earthworm cellulases were upregulated in response to either a bacterial (Bacillus subtilis or Escherichia coli) or LPS challenge. After the challenge, significant increases in cellulase 1 and cellulase 2 activity levels were observed within 8–16 and 16–24 h, respectively. In the coelomic fluid, both activities were significantly upregulated at 8 h post-injection with B. subtilis. Based on RNA sequencing, cellulase-related mRNAs encoding beta-1,4-endoglucanases were upregulated by 3-fold within 6 h after B. subtilis injection. Our results clearly demonstrated that earthworm cellulases are upregulated by bacterial challenge at the mRNA and protein levels. These results support the view that earthworm cellulases act as inducible humoral effectors of innate immunity against bacterial infection. • Cellulase activity levels were upregulated by a bacterial or LPS challenge. • RNA-seq discovered that cellulase-related mRNAs increased by B. subtilis injection. • Earthworm cellulases could act as immune effectors against bacterial infection. [ABSTRACT FROM AUTHOR]

Ivermectin (IVM) is a dewormer commonly utilized in animal farming. Nevertheless, there is a deficiency of research on the bioecotoxicity of IVM in soil. In this study, earthworms were utilized as test animals to investigate the ecotoxicological impacts of IVM. The experiment lasted 28 days and involved adding varied doses of IVM to a culture substrate of soil mixed with cow dung and feeding it to earthworms. The experiment entailed recording earthworm weight, number of earthworm cocoons, histological damage, oxidative stress indicators, and gene expression levels. The analysis results showed that earthworm growth and reproduction were hampered by IVM. Moreover, pathological damage to the earthworms increased with increasing IVM concentration, which caused increased oxidative damage to the earthworms. These findings offer a summary of the impact of IVM on earthworms and a reference point for future research examining the ecological implications of IVM. • IVM reduces the growth and reproduction of earthworms. • IVM caused pathological damage to earthworms. • IVM induced oxidative stress in earthworms. • This study provides a reference for the effects of antiparasitic drugs on earthworms. [ABSTRACT FROM AUTHOR]

With increasing urbanization and industrialization, the scarcity of freshwater is becoming rampant. To counteract this, authorities all over the world are forced to consider the treatment and reuse of the wastewater produced by either industries or domestic units. After an extensive literature survey, vermifiltration coupled with/without macrophyte has been identified as one of the best sustainable, natural and eco-friendly technology for the treatment and reuse of wastewater. Till date, it has been successfully applied for treating domestic wastewater. However, the results from very limited industrial applications are also encouraging and proving its worth for industrial wastewater remediation. The present review on vermifiltration deals with the mechanisms involved and its current status for the remediation and reutilisation of the effluents generated from domestic and industrial premises. The review successfully identifies and explicitly discusses the mechanisms involved in the vermifiltration. The review exhaustively discusses the performance of vermifiltration and identifies the factors contributing to the performance of vermifiltration, which could be of help in designing of the field scale vermifilter based treatment plant. The review identifies the limitations associated with the vermifiltration and suggests possible alternatives, aimed to improve its performance and applicability. The aim of this review is to bring the attention of prospective researchers to study each and every aspect related to the vermifiltration so that it may be adopted as a reliable and dependable technology for the remediation of several industrial effluents meeting the concept of "Zero discharge". • The review successfully elaborates the mechanisms involved in vermifiltration. • Application of vermifiltration in domestic and industrial context is discussed. • The review discusses the limitations associated with the vermifiltration. • The review suggests the ways to counter the limitations of vermifilters. • The review successfully gives a thrust to apply vermifiltration to the field scale. [ABSTRACT FROM AUTHOR]

This study investigated the effect of vermicomposting on the degradation of rice straw and kitchen waste. Different ratios of straw and kitchen waste mixtures were used as feedstocks. After vermicomposting the substrates for 45 days under 20–25 °C moisture 60%, the vermicomposting resulted in a significant increase in phosphorous (31.38–55.89%) and potassium (33.40–63.15%), whereas a decrease was seen in TOC (38.24–43.49%) as well as TN (9.01–32.52%). The growth rate of earthworm (Eisenia foetida) was obtained in all feedstocks, the optimal rice straw/kitchen waste ratio for the earthworm growth was 3/2, excessive kitchen waste as negative impacts on the growth of earthworms. The result indicated that vermicomposting rice straw and kitchen waste with Eisenia foetida promoted nutrition content in a short period of time. • Kitchen waste and rice straw were treated with the earthworm, Eisenia foetida. • Earthworm convert kitchen waste and rice straw into nutrient rich vermicompost. • Earthworm treated feedstock is more fragmented and mineralized than raw materials. [ABSTRACT FROM AUTHOR]

Abstract Pentachloronitrobenzene (PCNB) has been widely utilized as a fungicide to control diseases. However, toxic effect data of PCNB on terrestrial invertebrate are not available till now. Herein, the earthworms (Eisenia fetida) were exposed to soil containing different levels of PCNB. Mortality, weight, accumulation, and physiological indexes of earthworms were determined on certain days. PCNB inhibited the growth of earthworms and induced a significant increase in the activity of antioxidative enzymes. ROS, SOD, and MDA of earthworms in the highest treatment group were 6.8, 4.4, and 3.8 times higher than those in the control group, respectively. In addition, earthworm coelomocytes were successfully extracted, cultured, and innovatively employed in in-vitro toxicity test to evaluate the toxic effect of PCNB. The biomarkers utilized in in-vitro toxicity test, including cell viability, intracellular ROS and extracellular LDH showed significant correlations with the PCNB in the culture media, indicating that the in-vitro toxicity test may serve as a useful tool for toxic assessment of pollutants to earthworms and other organisms. Graphical abstract fx1 Highlights • Coelomocytes of earthworm extracted and utilized in in-vitro toxicity test. • Extracellular LDH was innovatively introduced as biomarker in earthworm experiment. • Biomarkers in in-vitro toxicity test showed significant correlation with PCNB. [ABSTRACT FROM AUTHOR]

Abstract Previous research on soil remediation focused on soil properties and not on its effects on soil ecosystems. The present study investigated the adverse effects of soil physicochemical changes due to remediation on the biological indicators Chlorococcum infusionum and Chlamydomonas reinhardtii (algae) and Eisenia andrei (earthworm). Soil physicochemical properties, concentrations of total, bioavailable, and water-soluble heavy metals in soil were measured before and after remediation. Changes in soil pH, electrical conductivity, total nitrogen, and total phosphorous immediately after soil remediation were the primary causes of the biomass and photosynthetic activity inhibition observed in C. infusionum and C. reinhardtii , and the survival, normality, and burrowing behavior decrease observed in E. andrei in remediated soils showing dramatic changes in those properties. These findings suggest that remediated soils need some time to recover before restoring their functions, although heavy metals are no longer contaminating the soil. Highlights • Soil remediation can change soil pH, electrical conductivity, TN, and TP. • As soon as remediation, soil are not proper soil algae and earthworm. • Soils may need time to "recover" from remediation. [ABSTRACT FROM AUTHOR]

Treated wastewater is reclaimed to irrigate crops in a growing number of arid and semi-arid areas. In order to study the impacts of metallic nanoparticles (NPs) present in treated wastewater on soil ecosystems, a soil micro-ecosystem containing Arabidopsis thaliana plants, soil microorganisms, and Eisenia fetida earthworms was developed. The soil was irrigated with deionized water containing environmentally relevant concentrations of 70 µg/L of TiO 2 NPs; or 20 µg/L of an Ag mixture, which included 90% (w/w) Ag 2 S NPs, 7.5% (w/w) Ag0 NPs, and 2.5% (w/w) Ag+ to represent speciation of aged Ag NPs in treated wastewater; or a combination of the TiO 2 NPs and the Ag mixture to reflect the frequent presence of both types of materials in treated wastewater. It was found that TiO 2 NPs alone were not toxic to the soil micro-ecosystem. Irrigation water containing 20 µg/L of the Ag mixture significantly reduced the soil microbial biomass, and inhibited the growth of plants and earthworms; however, a combination of 70 µg/L of TiO 2 and 20 µg/L of Ag did not show toxic impact on organism growth compared to the Control of deionized water irrigation. Taken together, these results indicate the importance of investigating the effects of different nanomaterials in combination as they are introduced to the environment—with environmentally relevant concentrations and speciation—instead of only selecting a single NP type or residual ion. Moreover, the results of this study support the safe application of reclaimed water from wastewater treatment plants for use in agricultural lands in regard to limited concentrations of aged NPs (i.e., TiO 2 and Ag) if present in combination. • TiO 2 NPs at low concentration were not toxic to the soil micro-ecosystem. • The Ag mixture at low concentration brought toxicity to the soil micro-ecosystem. • TiO 2 appeared to mitigate the harmful impact of Ag at the studied concentrations. • Importance of investigating impact of combinations of aged NPs in irrigation water. [ABSTRACT FROM AUTHOR]

Abstract Preservation of the soil resources stability is of high importance for ecosystems, particularly in the current era of environmental change, which presents a severe pollution burden (e.g. by heavy metals) to soil fauna. Gut microbiomes are becoming recognized as important players in organism health, with comprehension of their perturbations in the polluted environment offering new insights into the nature and extent of heavy metal effects on the health of soil biota. Our aim was to investigate the effect of environmentally relevant heavy metal concentrations of cadmium (Cd) on the earthworm (Lumbricus terrestris) gut microbiota. Our results revealed that Cd exposure led to perturbations of earthworm gut microbiota with an increase in bacteria previously described as heavy metal resistant or able to bind heavy metals, revealing the potential of the earthworm-gut microbiota system in overcoming human-caused heavy metal pollution. Furthermore, an 'indicator species analysis' linked the bacterial genera Paenibacillus , Flavobacterium and Pseudomonas , with Cd treatment, suggesting these bacterial taxa as biomarkers of exposure in earthworms inhabiting Cd-stressed soils. The results of this study help to understand the impact of anthropogenic disturbance on soil fauna health and will have implications for environmental monitoring and protection of soil resources. Highlights • Environmentally relevant concentrations of Cd alter earthworm gut microbiota. • Heavy metal resistant bacterial taxa increased in the gut as a result of Cd intake. • Several bacterial indicators were defined as potential biomarkers of exposure to Cd. • Many indicators belong to genera Paenibacillus , Flavobacterium and Pseudomonas. [ABSTRACT FROM AUTHOR]

Abstract Managing municipal green waste is a challenge to municipalities, partly because of the slow rate of decomposition of green waste during composting due to its high lignin and cellulose contents. Hence, this study evaluated the effect of alkyl polyglycoside (APG), a biosurfactant, and the earthworm Eisenia fetida on the composting process. Addition of APG and E. fetida significantly increased total bacteria, cellulolytic fungi, phosphate solubilizing bacteria and nitrogen fixing bacteria populations, and the activities of cellulase, urease and alkaline phosphatase in composts as compared with the control. The APG and earthworm treatments also increased surface roughness and porosity of the green waste; Compared with control, APG and earthworm addition increased the degradation rate of TOC, lignin and cellulose by 5.9–17.9, 10.3–32.0 and 10.8–18.8%, respectively, and resulted in better compost quality, as was reflected in the neutral pH, higher cation exchange capacity (CEC) and nutrient concentrations (N, P, K, Ca, Mg, Fe, Cu, Zn, Mn). Final germination percentage and growth rate of tomato, eggplant and pepper seedlings were higher (P < 0.05) or similar in all composts produced with the addition of APG and earthworm, while plant growth was lower (P < 0.05) in the compost produced with the control than in peat substrate. The combination of APG+ E. fetida enhanced the decomposition of green waste and improved final compost quality the most. Further research is needed to determine the best level of APG addition and optimum earthworm density for composting green waste. Highlights • Alkyl polyglycoside (APG) and/or E. fetida addition enhanced lignin degradation. • APG and/or E. fetida addition increased disaggregation of green waste. • APG and/or fetida addition improved nutrient availability in compost. • The compost supports the growth of tomato, eggplant and pepper seedlings. [ABSTRACT FROM AUTHOR]

Abstract Samples of soil, earthworms, and tree roots from the forest ecosystem in the Dexing Pb/Zn mining area of Jiangxi Province were collected and the status of trace metal pollution analyzed to assess potential ecological risks. Chemometric and geographic information system methods were used to identify and describe the spatial distributions and the main contamination sources of trace metals. The order of potential ecological risks of trace metals in this area are as follows: cadmium (Cd) > arsenic (As) > copper (Cu) > nickel (Ni) > lead (Pb) > chromium (Cr) > zinc (Zn). Elemental spatial distribution maps showed the existence of zones heavily polluted by trace metals around the mining area. Earthworms and roots of three tree species were also heavily contaminated, with concentrations of trace metals in earthworms much higher than in previous studies. The potential ecological risk index and other soil quality indices indicated that soil had moderate to severe contamination and there were high ecological risks, with Cd making the greatest contribution. Multivariate statistical analyses showed that Cd, As, Cu, Pb, and Zn in soil came from a mining activity source, whereas Ni and Cr primarily originated from a natural source. Graphical abstract fx1 Highlights • Quality indicators, multivariate analysis and GIS mapping used to assess the pollution and ecological risk of trace elements. • Forest soils were polluted by trace metals with moderate risk. • Trace metals in the soil of the mining area are potentially harmful to organism. [ABSTRACT FROM AUTHOR]

Abstract The effect of gamma radiation delivered over 24 h on the induction of bystander signals of three earthworm species exposed in vivo was investigated: A. chlorotica , A. caliginosa , and E. tetraedra. Worms were exposed to external gamma irradiation (Co-60 source) for 24 h and samples of head, body, and clitellum were dissected from exposed and control worms and placed in culture medium for 24 h at 19 C. The harvested medium was filtered and assayed for expression of bystander signals using both clonogenic and mitochondrial reporter assays. Different responses were observed in the different species and in the different tissues. A. chlorotica worm-treated reporters show insignificant mitochondrial response for all sections, yet a significant clonogenic reduction in survival for body sections. A. caliginosa worm-treated reporters show a significant mitochondrial response for some sections and insignificant mitochondrial response and insignificant reduction in clonogenic survival for the rest. E. tetraedra worms from a control site show significant evidence of bystander signalling, measured by mitochondrial response in reporter cells, for all sections while those harvested from a contaminated site show insignificant changes in baseline signalling when exposed to the challenge dose. In vivo exposure of earthworm species shows evidence of bystander signalling using two different reporter assays. This effect varied between the different species and tissues. There is also evidence of attenuated bystander signalling in worms harvested from a site contaminated with radiation. Highlights • Three earthworm species were irradiated using a gamma source in vivo and assayed for bystander signalling. • Two species show evidence of bystander signalling determined by both survival and mitochondrial reporter assays. • Another also shows evidence of bystander signalling and an adaptive response to the signal after chronic exposure. • There is evidence that the nature of radiation acting on living organisms must be appreciated on a system-level. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six new earthworm toll-like receptor genes (Ean-TLR1 / 2 / 3 / 4 / 5 / 6) were characterized. • Essential signaling elements are conserved in the Toll/IL-1 receptor domain. • All but Ean-TLR3 gene was upregulated by Gram-positive but not Gram-negative bacteria. • Pathogenic ligand recognition by earthworm TLRs is likely to be specific and diverse. Toll-like receptors (TLRs), an ancient and well-conserved group of pattern recognition receptors (PRRs), recognize conserved pathogen-associated molecular patterns. TLRs consist of three domains: the extracellular N -terminal domain, containing one or more leucine-rich repeats (LRRs), responsible for the recognizing and binding of antigens; the type-I transmembrane domain; and the intracellular domain known as the Toll/Interleukin-1 receptor (TIR) domain required for the downstream signaling pathway. We identified six new full-length complementary DNA (cDNA) sequences, Ean-TLR1 / 2 / 3 / 4 / 5 / 6. The deduced amino acid sequences indicate that Ean-TLRs consist of one signal peptide, one LRR N -terminal domain (Ean-TLR4/5), varying numbers of LRRs, one (Ean-TLR1/2/3/4/5) or two (Ean-TLR6) LRR C-terminal domains, one type-I transmembrane domain, and a TIR domain. In addition, a TIR domain alignment revealed that three conserved motifs, designated as Box 1, Box 2, and Box 3, contain essential amino acid residues for downstream signaling activity. Phylogenetic analysis of earthworm TLRs generated two separate evolutionary branches representing single (sccTLR) and multiple (mccTLR) cysteine cluster TLRs. Ean-TLR1/2/3/4 (sccTLR type) and Ean-TLR6 (mccTLR type) were clustered with corresponding types of previously reported earthworm TLRs as well as TLRs from Clitellata and Polychaete. As PRRs, earthworm TLRs should be capable of sensing a diverse range of pathogens. Except for Ean-TLR3 , which was not responsive to any bacteria, earthworm TLR expression was significantly induced by Gram-positive but not Gram-negative bacteria. Moreover, it is likely that earthworms can differentiate between different species of Gram-positive bacteria via their TLR responses. The ligand specificity of earthworm TLRs suggests that their pathogenic ligand recognition is likely to be as specific and diverse as the mammalian TLR pathogen-sensing system. [ABSTRACT FROM AUTHOR]

As a novel neonicotinoids insecticide, acetamiprid has been widely used worldwide. In this study, a laboratory test was conducted to expose earthworms ( Eisenia fetida ) to artificial soil spiked with various concentrations of acetamiprid (0, 0.05, 0.10, 0.25 and 0.50 mg/kg of soil) respectively after 7, 14, 21 and 28 d. Reactive oxygen species (ROS) generation, antioxidant enzymes activity including superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferases (GST), malondialdehyde (MDA) content, and DNA damage were determined in earthworms. The ROS level increased in varying degrees at most exposure concentrations. The SOD activity was not significantly affected. The CAT activity was increased in the beginning, then gradually suppressed and resumed to the control level at the end, with the maximum change (171%) occurred at 14 d for 0.05 mg/kg. The GST activity was induced at 7 d, and then inhibited, with the maximum change (67.6%) occurred at 14 d for 0.50 mg/kg. The MDA content had a tendency that increasing at the first and decreasing at the end. The olive tail moment (OTM) in comet assay reflected a dose-dependent relationship, and DNA damage initially increased and then decreased over time. The results suggest that the sub-chronic exposure of acetamiprid can cause oxidative stress and DNA damage of earthworm and change the activity of the anti-oxidant enzyme. In addition, ROS content and DNA damage can be good indicators for assessing environmental risks of acetamiprid in earthworms. [ABSTRACT FROM AUTHOR]

Because the extensive use of Cu-based fungicides, the accumulation of Cu in agricultural soil has been widely reported. However, little information is known about the bioavailability of Cu deriving from different fungicides in soil. This paper investigated both the distribution behaviors of Cu from two commonly used fungicides (Bordeaux mixture and copper oxychloride) during the aging process and the toxicological effects of Cu on earthworms. Copper nitrate was selected as a comparison during the aging process. The distribution process of exogenous Cu into different soil fractions involved an initial rapid retention (the first 8 weeks) and a following slow continuous retention. Moreover, Cu mainly moved from exchangeable and carbonate fractions to Fe-Mn oxides-combined fraction during the aging process. The Elovich model fit well with the available Cu aging process, and the transformation rate was in the order of Cu(NO 3 ) 2 > Bordeaux mixture > copper oxychloride. On the other hand, the biological responses of earthworms showed that catalase activities and malondialdehyde contents of the copper oxychloride treated earthworms were significantly higher than those of Bordeaux mixture treated earthworms. Also, body Cu loads of earthworms from different Cu compounds spiked soils were in the following order: copper oxychloride > Bordeaux mixture. Thus, the bioavailability of Cu from copper oxychloride in soil was significantly higher than that of Bordeaux mixture, and different Cu compounds should be taken into consideration when studying the bioavailability of Cu-based fungicides in the soil. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo- p -dioxins/dibenzofurans (PCDD/Fs), together with polycyclic aromatic hydrocarbons (PAHs), represent highly toxic and persistent organic environmental pollutants, especially due to their capability for bioaccumulation in fatty tissues. To observe the environmentally relevant effect of these compounds on earthworms, two soils naturally contaminated with PCDD/Fs and PAHs were used in our experiments. We focused on the role of CuZn- and Mn-superoxide dismutases. We assembled a full-length sequences of these molecules from Eisenia andrei earthworm and confirmed their activity. We demonstrated the significant reduction of CuZn-SOD on both mRNA and enzyme activity levels and increased levels of reactive oxygen species in earthworms kept in PCDD/F-polluted soil, which corresponds to the observed histopathologies of the earthworm intestinal wall and adjacent chloragogenous tissue. The results show an important role of CuZn-SOD in earthworm tissue damage caused by PCDD/Fs present in soil. We did not detect any significant changes in the mRNA expression or activity of Mn-SOD in these earthworms. In earthworms maintained in PAH-polluted soil the activity of both CuZn-SOD and Mn-SOD significantly increased. No histopathological changes were detected in these worms, however significant decrease of coelomocyte viability was observed. This reduced viability was most likely independent of oxidative stress. [ABSTRACT FROM AUTHOR]

The fate of hydrophobic organic contaminants (HOCs) in soil-earthworm systems is an important foundation for soil pollution risk assessment and pollution control. Equilibrium partitioning is considered to be the main mechanism by which HOCs enter earthworms and, as such, a mechanistic model has been developed to estimate the earthworm-water partition coefficients ( K w-w ). In the present study, the adsorption of phenanthrene (PHE) by earthworm tissue was investigated to evaluate the validity of the mechanistic models. Results revealed that K w-w derived from the mechanistic model (346.90) was lower than that derived from the sorption experiments (410.76), indicating that apart from lipid fractions, other components in earthworms, such as protein fractions, might also play an important role in the adsorption of HOCs by earthworm. Besides, the difference between the mechanistic model for earthworm and partition-limited model used for plants are few, indicating that uptake and accumulation mechanisms of HOCs by earthworms and plants are highly consistent internally and are, essentially actually identical. It is also suggested that environmental fate of HOCs in soil-soil biota systems is dominated by their high hydrophobicity. Based on these conclusions, an improved mechanistic model for predicting the uptake of organic contaminants by earthworms has been proposed, which needs to be further evaluated. Furthermore, the feasibility of using vermiaccumulation in vermiremediation of soil contaminated by HOCs was discussed. The adsorption of PHE by earthworm sub-organism fractions (pre-clitellum, clitellum and post-clitellum) and tissue fractions (body wall and gut) were also investigated to interpret the distribution pattern of HOCs in earthworms. At the sub-organism level, the adsorption capacity of PHE by different regions of the earthworm followed the order: post-clitellum > clitellum > pre-clitellum, meaning the distribution of PHE along the earthworm contributes not only to their chemical composition but also to the life activity of earthworms such as circular system. At the tissue level, the gut showed greater affinity with PHE than that of the body wall indicating that the distribution of PHE is mainly due to chemical components at the tissue levels. These results might provide additional understanding of the fate of HOCs in soil-earthworm systems. [ABSTRACT FROM AUTHOR]

Cytochrome P450 (CYP450) enzymes are a family of hemoproteins primarily responsible for detoxification functions. Earthworms have been used as a bioindicator of soil pollution in numerous studies, but no CYP450 gene has so far been cloned. RT-PCR and RACE-PCR were employed to construct and sequence the CYP450 gene DNA from the extracted mRNA in the earthworm Eisenia fetida . The cloned gene (EW1) has an open reading frame of 477 bp. The 3′-terminal region contained both the consensus and the signature sequences characteristic of CYP450. It was closely related to the CYP450 gene from the flatworm genus Opisthorchis felineus with 87% homology. The predicted structure of the putative protein was 97% homologous to human CYP450 family 27. This gene has been deposited in GenBank (accession no. KM881474 ). Earthworms ( E. fetida ) were then exposed to 1, 10, 100, and 500 mg kg −1 enrofloxacin in soils to explore the mRNA expression by real time qPCR. The effect of enrofloxacin on mRNA expression levels of EW1 exhibited a marked hormesis pattern across the enrofloxacin dose range tested. This is believed to be the first reported CYP450 gene in earthworms, with reference value for molecular studies on detoxification processes in earthworms. [ABSTRACT FROM AUTHOR]

Pesticides and heavy metals commonly coexist in soil. In this study, the influence of Cd and Cu on the toxicity of rac -dinotefuran and the enantioselective behavior of dinotefuran enantiomers in soil-earthworm microcosms were investigated. The acute toxic tests showed that S -dinotefuran has higher toxic than that of R -dinotefuran. The rac -dinotefuran and Cd has an antagonistic effect on earthworms, and the Cu and rac -dinotefuran has a synergistic effect. Earthworms maybe promoted the enantioselective behavior of dinotefuran in soil. Co-exposure to Cd or Cu inhibited the dissipation of dinotefuran enantiomers (S -dinotefuran and R -enantiomers), and slightly reduced the enantioselectivity in soil. The earthworms were found to be preferentially enriched with S -dinotefuran. However, Cd or Cu attenuated the accumulation of dinotefuran enantiomers in earthworms and decreased the enantioselectivity. The effect of Cd and Cu on the environmental behaviors of dinotefuran enantiomers were correlated positively with the dose of Cd/Cu. These results showed that Cd and Cu alter the environmental behaviors and the toxicity of dinotefuran enantiomers in soil-earthworm microcosms. Thus, the influence of coexistent heavy metals on the ecological risk assessment of chiral pesticides should be considered. [Display omitted] • Toxicity of rac -dinotefuran with Cd is antagonistic, while that with Cu is synergistic. • Cu/Cd decelerates dinotefuran degradation in soil. • Earthworms in soil lead to EF increase of dinotefuran enantiomers. • Cd/Cu reduces the accumulation of dinotefuran enantiomers in earthworm. • Cd/Cu decreases the enantioselectivity of dinotefuran enantiomers in earthworm. [ABSTRACT FROM AUTHOR]

Our knowledge of the phylogeny of the earthworm genus Amynthas under the family Megascolecidae, which is comprised of a huge number of species, is very limited compared to the better-known and much smaller family Lumbricidae. In order to investigate the phylogenetic relationships among the species within the genus Amynthas , which is the largest genus of the Megascolecidae family, nuclear and mitochondrial DNA sequences of 77 species, including 76 in-group Amynthas species collected from South China and 1 out-group species, were analyzed. A 5402 bp segments composed of whole nuclear 18 S rDNA and the mitochondrial genes COI, COII, ND1, 12 S, and 16 S was assembled from 77 species. Maximum Likelihood and Bayesian analyses of the concatenated sequences were performed. The results revealed evolution of two geographically independent lineages, both showing the ancestral state of two pairs of spermatheca (Sp.p 7/8/9). We found the species groups described by Sims and Easton (1972) to be non-monophyletic, and the origin of the parthenogenetic species group to likely be a quadthecal ancestor. These results provide modest evidence in support of an Indochinese peninsula origin of the Chinese Amynthas species and divergence of the genus once it had spread to mainland China. The findings of this study are consistent with a divergence scenario that resulted in at least one branch spreading to the Southeast of China and another branch spreading to the Southwest of China, but further research is required to confirm this interpretation of the Amynthas phylogeny. [ABSTRACT FROM AUTHOR]

The Indigo carmine (IC) dye has been widely used in textile industries, even though it has been considered toxic for rats, pigs and humans. Owing to its toxicity, wastes containing this compound should be treated to minimize or eliminate their toxic effects on the biota. As an alternative to wastewater treatment, advanced oxidative processes (AOPs) have been highlighted due to their high capacity to destruct organic molecules. In this context, this study aimed to evaluate Indigo Carmine toxicity to soil organisms using the earthworm Eisenia andrei as a model-organism and also verify the efficiency of AOP in reducing its toxicity to these organisms. To this end, lethal (mortality) and sub-lethal (loss or gain of biomass, reproduction, behavior, morphological changes and immune system cells) effects caused by this substance and its degradation products in these annelids were evaluated. Morphological changes were observed even in organisms exposed to low concentrations, while mortality was the major effect observed in individuals exposed to high levels of indigo carmine dye. The organisms exposed to the IC during the contact test showed mortality after 72 h of exposure (LC 50 = 75.79 mg cm - 2 ), while those exposed to photoproducts showed mortality after 48 h (LC 50 = 243 min). In the chronic study, the organisms displayed a mortality rate of 14%, while those exposed to the photoproduct reached up to 32.7%. A negative influence of the dye on the reproduction rate was observed, while by-products affected juvenile survival. A loss of viability and alterations in the cellular proportion was verified during the chronic test. However, the compounds did not alter the behavior of the annelids in the leak test (RL ranged from 20% to 30%). Although photocatalysis has been presented as an alternative technology for the treatment of waste containing the indigo carmine dye, this process produced byproducts even more toxic than the original compounds to E. andrei. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate the bioavailability of polycyclic aromatic hydrocarbons (PAHs) in industrial and agricultural soils using chemical methods and a bioassay, and to study the relationships between the methods. This was conducted by comparing the quantities of PAHs extracted from two manufactured gas plant (MGP) soils and an agricultural soil with low level contamination by solid-phase micro-extraction (SPME) and Tenax-TA extraction with the quantities taken up by the earthworm ( Eisenia fetida ). In addition, a biodegradation experiment was conducted on one MGP soil (MGP-A) to clarify the relationship between PAH removal by biodegradation and the variation in PAH concentrations in soil pore water. Results demonstrated that the earthworm bioassay could not be used to examine PAH bioavailability in the tested MGP soils; which was the case even in the diluted MGP-A soils after biodegradation. However, the bioassay was successfully applied to the agricultural soil. These results suggest that earthworms can only be used for bioassays in soils with low toxicity. In general, rapidly desorbing concentrations extracted by Tenax-TA could predict PAH concentrations accumulated in earthworms (R 2 =0.66), while SPME underestimated earthworm concentrations by a factor of 2.5. Both SPME and Tenax extraction can provide a useful tool to predict PAH bioavailability for earthworms, but Tenax-TA extraction was proven to be a more sensitive and precise method than SPME for the prediction of earthworm exposure in the agricultural soil. [ABSTRACT FROM AUTHOR]

Use of avoidance tests is a quick and cost-effective method of assessing contaminants in soils. One option for assessing earthworm avoidance behavior is a two-section test, which consists of earthworms being given the choice to move between a test soil and a control substrate. For ecological relevance, tested soils should be field-contaminated soils. For practical reasons, artificial soils are commonly used as the control substrate. Interpretation of the test results compromised when the test soil and the artificial substrate differ in their physico-chemical properties other than just contaminants. In this study we identified the physico-chemical properties that influence avoidance response and evaluated the usefulness of adjusting these in the control substrate in order to isolate metal-driven avoidance of field soils by earthworms. A standardized two-section avoidance test with Eisenia fetida was performed on 52 uncontaminated and contaminated (Cu >155 mg kg −1 , As >19 mg kg −1 ) agricultural soils from the Aconcagua River basin and the Puchuncaví Valley in Chile. Regression analysis indicated that the avoidance response was determined by soil organic matter (OM), electrical conductivity (EC) and total soil Cu. Organic matter content of the artificial substrate was altered by peat additions and EC by NaCl so that these properties matched those of the field soils. The resultant EC 80 for avoidance (indicative of soils of “limited habitat”) was 433 mg Cu kg −1 (339 – 528 mg kg −1 95% confidence intervals). The earthworm avoidance test can be used to assess metal toxicity in field-contaminated soils by adjusting physico-chemical properties (OM and EC) of the artificial control substrate in order to mimic those of the field-collected soil. [ABSTRACT FROM AUTHOR]

In this study, earthworms Eisenia fetida ( E. fetida ) were exposed to a soil artificially contaminated with individual hexabromocyclododecane (HBCD) diastereoisomers (α-, β- and γ-HBCDs) to investigate the distribution, isomerization and enantiomer selectivity of HBCDs at tissue and subcellular levels. At the tissue level, the concentrations of HBCDs all followed the order of gut>bodyfluid>body wall, which suggested that earthworms accumulated HBCDs mainly via ingesting soil particles. At the subcellular level, the concentrations of HBCDs in an extracellular fraction consisting of granules, tissue fragment, cell membrane and intact cells (fraction A) were higher than those in an intracellular fractions consisting of the microsomal and cytosol (fraction B+C). This confirmed the passive diffusion during the distribution of HBCDs into the intracellular compartment. The distribution proportions of HBCDs varied among different tissue and subcellular fractions, and all changed over time within 14 days. The variable distributions of HBCDs in different fractions were a result of the comprehensive effects of dynamics and thermodynamics processes. The β- and γ-HBCDs were isomerized to α-HBCD in all tissue and subcellular fractions except for fraction C, and the isomerization ratios varied a lot, which seemed to be related to HBCDs residence time. The selective enrichment of (−) α-, (−) β and (−) γ-HBCDs was found in all fractions and this is consistent with that in the whole earthworm. Besides, the extents of enantio-selectivity did not change significantly among different tissue and subcellular fractions. [ABSTRACT FROM AUTHOR]

The bioaccumulation behavior of perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) was examined in three horticultural crops and earthworms. Two species, spinach ( Spinacia oleracea ) and tomato ( Solanum lycopersicum L.), were grown in field soil amended with a single application of biosolids (at agronomic rate for nitrogen), to represent the scenario using commercial biosolids as fertilizer, and the third crop, corn ( Zea mays ) was grown in spiked soil (~50 mg PFOS/kg soil, ~5 mg Deca-BDE/kg soil and a mixture of both, ~50 mg PFOS and ~5 mg Deca-BDE/kg soil) to represent a worst-case scenario. To examine the bioaccumulation in soil invertebrates, earthworms ( Eisenia andrei ) were exposed to the spiked soil where corn had been grown. PFASs and HFRs were detected in the three crops and earthworms. To evaluate the distribution of the compounds in the different plant tissues, transfer factors (TFs) were calculated, with TF values higher for PFASs than PBDEs in all crop plants: from 2 to 9-fold in spinach, 2 to 34-fold in tomato and 11 to 309-fold in corn. Bioaccumulation factor (BAF) values in earthworms were also higher for PFASs (4.06±2.23) than PBDEs (0.02±0.02). [ABSTRACT FROM AUTHOR]

Vermicomposting is the bio-oxidation and stabilization of organic matter involving relationships between the action of earthworms and microorganisms and the activation and dynamics of several enzyme activities. Semi-arid farmers to make (extra) money and organic production, produce their vermicompost using plant residues and animal manure, but there is no information about the final product generated. Thus, this study aimed to analyze the potential of vermicomposting with mixtures of animal manure and vegetable leaves in the development of Eisenia foetida , microbial biomass, and enzymatic activity in the semi-arid region, Brazil. The experimental design applied was randomized block in a 6 × 4 factorial scheme with four replicates, with six treatments (mixtures of cattle manure, goat manure, cashew leaves, and catanduva leaves) and evaluated at four-time intervals (30, 60, 90, and 120 days of vermicomposting). The treatments were placed in polyethylene pots in the same site, environmental conditions, and residues proportions as used by farmers. The characteristics analyzed were the number of earthworms (NE), total earthworm biomass (TEB) and earthworm multiplication index (MI), microbial biomass carbon (MBC), and activities of enzymes β-glucosidase, dehydrogenase, alkaline and acid phosphatases. The cattle manure vermicomposted shows the highest average values observed for NE, MI, TEB, MBC, and enzymatic activity, regardless of the plant leaves mix. In general, the enzymes activities were found in the descending order of β-glucosidase > alkaline phosphatase > dehydrogenase > acid phosphatase. The maturation dynamics of vermicompost were characterized by a decline in the microbial population and number and biomass of earthworms in the substrate and consequently a decrease in new enzyme synthesis and degradation of the remaining enzyme pool. Microbial biomass and enzymatic activity were indicators for changes in the quality of vermicompost. [Display omitted] • Mixtures of cattle manure, goat, and vegetable leaves were vermicomposted for 120 days. • Cattle manure was up to 2-times higher on multiplication and total biomass of Eisenia foetida than the goat. • Cattle manure shows higher activities of β-glucosidase, dehydrogenases, and phosphatases. • The maturation of vermicompost declined the microbial and earthworm populations, and enzymes. [ABSTRACT FROM AUTHOR]

Soil microbial nutrient limitations significantly affect microbial processes and thus ecosystem functionality, whereas the response of soil microbial nutrient limitations to earthworms has rarely been addressed but is urgently needed due to the important role of earthworms in terrestrial ecosystems. By examining how earthworms regulate plants' effects on microbial nutrient limitations under contrasting soil types and moisture conditions, we showed that plant presence reduced microbial carbon (C) limitation and such reduction was enhanced by earthworm. Plant presence increased soil microbial phosphorus (P) limitation in soils with earthworms in most cases. Additionally, the effects of plants on microbial nutrient limitations and their responses to earthworms were dependent on soil type (or soil nutrients) and moisture. These results suggested that earthworms have the potential to reduce soil microbial C limitation but enhance P limitation and highlighted the importance of nutrients and moisture in influencing the effects of earthworms and plants on microbial nutrient limitations. • Earthworms promoted plant growth greatly, especially under nutrient-limited soils. • Earthworms regulated the competition between plants and microbes on nutrients. • Earthworms reduced soil microbial carbon limitation but enhanced phosphorus limitation. [ABSTRACT FROM AUTHOR]

To overcome the scarcity of fresh water, concerned authorities worldwide are bound to think about remediation and reuse of domestic and industrial effluents. The present review study on integrated vermifiltrationwith hydroponic system explains mechanism followed in system and presently the reutilization and remediation of domestic and industrial effluents. It explains the result of integrated vermifiltration and recognizes factors such as clogging, hydraulic loading rate or rain on bed, salinity, and sunlight affect the efficiency of system. The study also focuses on limitations associated with vermifiltration and also suggestions have been made for enhancing the sustainability and performance of existing practices. After literature review, integrated vermifiltration with hydroponic system considered as a natural and eco-friendly method for treating polluted water. Active zone of vermifilter remove organics, nitrate from nitrogen, total and dissolved phosphorus from wastewater. The vermifiltration and integrated vermifiltration with macrophyte able remove chemical oxygen demand (COD) in the range (53.7%–64.4%) and (75.5%–82.8%) respectively. The integrated system reduces land consumption and wastewater can be reutilized in cultivation. • Mechanism behind integrated vermifiltration has been discussed. • Limitation and benefit of the system is identified. • Future research prospective has been identified and explained. • Integrated vermifiltation with hydroponic plants are able to degrade waste. • Reutilization of treated wastewater has also been identified. [ABSTRACT FROM AUTHOR]

Prothioconazole (PTC) is a widely used agricultural fungicide. In recent years, studies have confirmed that it exerts adverse effects on various species, including aquatic organisms, mammals, and reptiles. However, the toxicological effects of PTC on soil organisms are poorly understood. Here, we investigated the toxic effects, via oxidative stress and metabolic responses, of PTC on earthworms (Eisenia fetida). PTC exposure can induce significant changes in oxidative stress indicators, including the activities of superoxide dismutase (SOD) and catalase (CAT) and the content of glutathione (GSH), which in turn affect the oxidative defense system of earthworms. In addition, metabolomics revealed that PTC exposure caused significant changes in the metabolic profiles of earthworms. The relative abundances of 16 and 21 metabolites involved in amino acids, intermediates of the tricarboxylic acid (TCA) cycle and energy metabolism were significantly altered after 7 and 14 days of PTC exposure, respectively. Particularly, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that multiple different metabolic pathways could be disturbed after 7 and 14 days of PTC exposure. Importantly, these alterations in oxidative stress and metabolic responses in earthworms reveal that the effects of PTC on earthworms were time dependent, and vary with exposure time. In conclusion, this study highlights that the effects of PTC on soil organisms are of serious concern. [Display omitted] • PTC could affect the oxidative defense system of earthworms. • PTC could induce disturbance of metabolic profiles in earthworms. • Toxic effects of PTC on earthworms were time-dependent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Literature on essential oils (EOs) as effective insecticides and acaricides is steadily growing. • The non-target impact of EOs include lethal and sublethal effects. • We analyzed literature on EO toxicity towards biocontrol agents, pollinators, and soil invertebrates. • The modes of action leading to EO toxicity on non-target species are scarcely studied. • In the final section, a research agenda outlining major challenges in the field is proposed. The control of arthropod pests of agricultural importance is increasingly difficult due to the quick development of resistance in the targeted pest populations coupled to their massive non-target lethal and sublethal effects. This fostered the progressive banning of active ingredients at international and national levels, making pest management challenging. Reliable and environmentally sustainable pest control tools are required. Botanicals, with special reference to plant essential oils (EOs), can represent a broad source of active ingredients to develop effective insecticides and acaricides for agricultural purposes. In this context, our review analyzed the literature currently available about the lethal and sublethal activity of EOs on non-target terrestrial invertebrates in agricultural settings, including biological control agents (predators and parasitoids), pollinators and soil non-target species. Even if EO-based insecticides and acaricides are generally considered safer from a non-target point of view, a number of detrimental effects have been noted on biological control agents, including negative effects on respiration rate, reduced predatory ability and reduced parasitization rates, among others. Examples of sublethal effects experienced by pollinators exposed to EO-based pesticides are the reduction in the movement speed and distance travelled, while the toxicity of EO-based products on soil invertebrates is limited. Of note, the modes of action leading to EO toxicity on non-target species are scarcely studied. Further research on long-term non-target effects of EO-based pesticides in the field is still needed. [ABSTRACT FROM AUTHOR]

Botanical insecticides may provide alternatives to synthetic insecticides for controlling Spodoptera litura (F.) and they are target specific, biodegradable, and harmless to mammals. Eight natural chemical compounds with larvicidal activity were identified from fraction F 6 of C. guianensis flower extract. Probit analysis of 95% confidence level exposed an LC 50 of 223 ppm against S. litura third instar larvae. The growth and development of S. litura was affected in sub-lethal concentrations of fraction F 6 (50, 100, 150 and 200 ppm) compared to controls. Similarly nutritional indices values decreased significantly compared to controls. Fraction F 6 also damaged the gut epithelial layer and brush border membrane (BBM). This study also resolved the effects of toxicity to non-target earthworm treated with fraction F 6 and chemical pesticides (monotrophos and cypermethrin) and the results showed that fraction F 6 had no harmful effect on E. fetida . Further, fraction F 6 was eluted and sub fractions F 6c (50 ppm) showed high mortality against S. litura third instar larvae. Octacosane from fraction F 6c was established and confirmed using IR spectrum and HPLC. The time of retention of fraction F 6c was confirmed with the octacosane standard. Fraction F 6 of C. guianensis extract caused dose-dependent mortality towards S. litura . Octacosane in fraction F 6c was establish to be the prominent chemical compound associated with causing mortality but other compounds present in the fraction F 6 were shown to be associated with changes in development of S. litura at low dosages. S. litura at low dosage. Therefore, these findings suggest that octacosane may be one of the major insecticidal compounds affecting S. litura survival. [ABSTRACT FROM AUTHOR]

Although donated blood is the preferred material for transfusion, its limited availability and stringent storage requirements have motivated the development of blood substitutes. The giant extracellular hemoglobin (aka erythrocruorin) of the earthworm Lumbricus terrestris (LtEc) has shown promise as a blood substitute, but an efficient purification method for LtEc must be developed to meet the potential large demand for blood substitutes. In this work, an optimized purification process that uses divalent and trivalent metal salts to selectively precipitate human, earthworm, and bloodworm hemoglobin (HbA, LtEc, and GdHb, respectively) from crude solutions was developed. Although several metal ions were able to selectively precipitate LtEc, Zn 2+ and Ni 2+ provided the lowest heme oxidation and highest overall yield of LtEc. In contrast, Zn 2+ was the only metal ion that completely precipitated HbA and GdHb. Polyacrylamide gel electrophoresis (PAGE) analysis shows that metal precipitation removes several impurities to provide highly pure hemoglobin samples. Heme oxidation levels were relatively low for Zn 2+ -purified HbA and LtEc (2.4 ± 1.3% and 5.3 ± 2.1%, respectively), but slightly higher for Ni 2+ -purified LtEc (8.4 ± 1.2%). The oxygen affinity and cooperativity of the precipitated samples are also identical to samples purified with tangential flow filtration (TFF) alone, indicating the metal precipitation does not significantly affect the function of the hemoglobins. Overall, these results show that hemoglobins from several different species can be highly purified using a combination of metal (Zn 2+ ) precipitation and tangential flow filtration. [ABSTRACT FROM AUTHOR]

In the present work, the bioaccumulation behavior of 49 target emerging organic compounds (20 perfluoroalkyl substances, PFASs, and 29 halogenated flame retardants, HFRs) was studied in soil invertebrates ( Eisenia andrei ). Multi species soil systems (MS·3) were used to assess the fate and the effects associated with the application of four biosolids in agricultural soil on terrestrial soil organisms. Biosolid amendment increased concentrations 1.5–14-fold for PFASs, 1.1–2.4-fold for polybrominated diphenyl ethers, PBDEs, and 1.1–3.6-fold for chlorinated flame retardants, CFRs. Perfluorooctanesulfonate, PFOS, (25%) and BDE-209 (60%) were the predominant PFAS and HFR compounds, respectively, in biosolids-amended soils. Total concentrations (ng/g dry weight) in earthworms from biosolid-amended soils ranged from 9.9 to 101 for PFASs, from 45 to 76 for PBDEs and 0.3–32 for CFRs. Bioaccumulation factors (BAFs) were calculated to evaluate the degree of exposure of pollutants in earthworms. The mean BAF ranged from 2.2 to 198 for PFASs, 0.6–17 for PBDEs and 0.5–20 for CFRs. The relationship of PFAS and PBDE BAFs in earthworms and their log K ow were compared: PFAS BAFs increased while PBDE BAFs declined with increasing log K ow values. The effect of the aging (21 days) on the bioavailability of the pollutants in amended soils was also assessed: the residence time affected differently to the compounds studied. [ABSTRACT FROM AUTHOR]

The leaf litters of tree species, Acacia pycnantha (Ap) and Eucalyptus camaldulensis (Ec), predominantly growing at an abandoned copper (Cu) mine and mine soils including controls, were assessed for determining the metal toxicity and bioavailability using earthworm species Eisenia fetida , in a microcosm. Significant reduction in body weight as well as mortality were observed when the worms were introduced into mine soil or its combination with mine Ap litter. Virtually, there were no juveniles when the worms were fed on substratum that contained mine soil or mine leaf litter. The extent of bioaccumulation was dependent on water-soluble fraction of a metal in soil. The accumulation of cadmium, lead and copper in worm tissue was significantly more in treatments that received mine soil with or without mine leaf litter. However, the tissue concentration of zinc did not differ much in earthworms irrespective of its exposure to control or contaminated samples. Mine leaf litter from Ec, a known Cu hyperaccumulator, was more hospitable to earthworm survival and juvenile than that of Ap litter. Validation of the data on bioaccumulation of metals indicated that the mine leaf litter significantly contributed to metal bioavailability. However, it was primarily the metal concentration in mine soil that was responsible for earthworm toxicity and bioavailability. Our data also indicate that detrivores like earthworm is greatly responsible for heavy metal transfer from mines into the ecosystem. [ABSTRACT FROM AUTHOR]

Serious concerns have been expressed about potential risks of manufactured TiO 2 NPs. In this research, toxicity of nanoparticulate and bulk TiO 2 were examined to the earthworm Pheretima hawayana. The 24-h median lethal concentration (LC 50 ) and sublethal endpoints were assessed. Both NPs and their bulk counterparts were toxic. The 24-h LC 50 for TiO 2 NPs (145.36 mg kg −1 ) was highly toxic than that of bulk TiO 2 (357.77 mg kg −1 ). The aim of the present work is to evaluate the suitability of P. hawayana and its biochemical responses to be used as a bioindicator organism and biomarkers of TiO 2 toxicity. Earthworms were exposed to three sublethal concentrations of TiO 2 NPs (1, 10 and 100 µg kg −1 ) for 28 days to test acetylcholinesterase (AChE), antioxidant enzymes (superoxide dismutase: SOD and catalase: CAT) activities and MDA content. The response of the antioxidant enzymes combined with AChE inhibition and MDA accumulation indicated that TiO 2 NPs could induce significant impairments to the earthworms at the actual environment tested concentrations. The results pointed out the high sensitivity of the antioxidant and oxidative stress related responses to TiO 2 NPs exposure, demonstrating their usefulness in environmental monitoring and risk assessment. The study highlights also the usefulness of earthworm P. hawayana as potential bioindicator species for assessing the risk of nanoparticles environmental contamination. [ABSTRACT FROM AUTHOR]

Several previous studies highlighted the importance of using field-collected soils—and not artificially-contaminated soils—for ecotoxicity tests. However, the use of field-collected soils presents several difficulties for interpretation of results, due to the presence of various contaminants and unavoidable differences in the physicochemical properties of the tested soils. The objective of this study was to estimate thresholds of metal toxicity in topsoils of 24 agricultural areas historically contaminated by mining activities in Chile. We performed standardized earthworm reproduction tests (OECD 222 and ISO 11268-2) with Eisenia fetida . Total soil concentrations of Cu, As, Zn, and Pb were in the ranges of 82–1295 mg kg −1 , 7–41 mg kg −1 , 86–345 mg kg −1 , and 25–97 mg kg −1 , respectively. In order to differentiate between the effects of different metals, we used regression analysis between soil metal concentrations and earthworm responses, as well as between metal concentrations in earthworm tissues and earthworm responses. Based on regression analysis, we concluded that As was a metal of prime concern for Eisenia fetida in soils affected by Cu mining activities, while Cu exhibited a secondary effect. In contrast, the effects of Zn and Pb were not significant. Soil electrical conductivity was another significant contributor to reproduction toxicity in the studied soils, forcing its integration in the interpretation of the results. By using soils with electrical conductivity ≤0.29 dS m −1 (which corresponds to EC 50 of salt toxicity to Eisenia fetida ), it was possible to isolate the effect of soil salinity on earthworm reproduction. Despite the confounding effects of Cu, it was possible to determine EC 10 , EC 25 and EC 50 values for total soil As at 8 mg kg −1 , 14 mg kg −1 and 22 mg kg −1 , respectively, for the response of the cocoon production. However, it was not possible to determine these threshold values for juvenile production. Likewise, we were able to determine EC 10 , EC 25 and EC 50 of earthworm tissue As of 38 mg kg −1 , 47 mg kg −1 , and 57 mg kg −1 , respectively, for the response of the cocoon production. Finally, we determined the no-observed effect concentration of tissue As in E. fetida of 24 mg kg −1 . Thus, earthworm reproduction test is applicable for assessment of metal toxicity in field-collected soils with low electrical conductivity, while it might have a limited applicability in soils with high electrical conductivity because the salinity-induced toxicity will hinder the interpretation of the results. [ABSTRACT FROM AUTHOR]

Flupyradifurone (FLU) has great application potential in agricultural production as a new generation of neonicotinoid insecticide after imidacloprid. Nevertheless, the toxic effects of FLU on non-target soil organisms remain unclear, resulting in considerable environmental risks. We evaluated the acute and subchronic toxicities of FLU to earthworms. The results of acute toxicity show that the median lethal concentration (LC 50) values (14 d) of FLU were 186.9773 mg kg−1 for adult earthworms and 157.6502 mg kg−1 for juveniles, respectively. The subchronic toxicity of FLU that focused on the activities of antioxidant and detoxication enzymes showed the superoxide dismutase (SOD), catalase (CAT), and glutathione-S transferase (GST) activities in earthworms increased while the peroxidase (POD) and acetylcholinesterase (AChE) activities decreased after exposure to FLU. Oxidative damage analyses revealed that the reactive oxygen species (ROS) level and malonaldehyde (MDA) content in earthworms were increased by FLU, resulting in DNA damage. Transcriptomics and RT-qPCR confirmed that FLU influenced the expression of genes related to antioxidant response and detoxification of earthworms. Ultimately detoxification metabolism, environmental information processing, cell processes, and immune system pathways are significantly enriched to respond jointly to FLU. Our study fills the gaps in the toxicity of FLU to earthworms, providing a basis for its risk assessment of soil ecosystems and non-target biological toxicity. [Display omitted] • Flupyradifurone (FLU) was low toxic to adult and juvenile earthworms from LC 50. • FLU led to oxidative stress, lipid and DNA damage to adult earthworms. • Transcriptomics revealed oxidative stress and detoxification mechanisms in earthworms. • Integrated biomarker response indicated FLU toxicity had dose and time effects. [ABSTRACT FROM AUTHOR]

In recent years, enormous amounts of spent mushroom substrate (SMS) have been generated because of the rapid development of mushroom production. Since the conventional disposal methods of these residues can cause serious environmental problems, alternative waste management techniques are required to ensure sustainable agriculture. However, SMS might be not suitable for vermicomposting when used alone. Therefore, the primary purpose of this study was to investigate the effect of Azolla microphylla (Azolla) biomass, eggshells, fruit peels, and cassava pulp on the biodegradation process of SMS. The results showed the treatments supplemented with cassava pulp and fruit peel waste improved the growth of earthworms, while the carbon-to-nitrogen ratio of these vermicomposts decreased significantly (p < 0.05) due to the improved total nitrogen contents (7.64 g kg−1 and 6.71 g kg−1). Concerning the degradation process and the vermicompost quality, the addition of these agro-residues facilitated the enzyme activities (cellulase, urease, and alkaline phosphatase) and increased the total macronutrient (P, K, Mg, and Ca) and phytohormone (fruit peel waste: AA, GA3, and cytokinin; cassava pulp: cytokinin) contents of the final products compared to the control treatment. On the other hand, Azolla had no additional effect on the fecundity and growth of Eudrilus eugenia. Meanwhile, the treatment supplemented with eggshells was high in Mg (7.15 g kg−1) and Ca (305.6 g kg−1). Overall, the combined decomposition of SMS-based bedding material with Azolla , eggshells, fruit peel waste, and cassava pulp resulted in mature organic fertilizers with improved chemical properties. [ABSTRACT FROM AUTHOR]

The enhanced production and environmental release of Buckminsterfullerene (C 60 ) nanoparticles will likely increase the exposure and risk to soil dwelling organisms. We used 1 H NMR-based metabolomics to investigate the response of Eisenia fetida earthworms to sub-lethal C 60 nanoparticle exposure in both contact and soil tests. Principal component analysis of 1 H NMR data showed clear separation between controls and exposed earthworms after just 2 days of exposure, however as exposure time increased the separation decreased in soil but increased in contact tests suggesting potential adaptation during soil exposure. The amino acids leucine, valine, isoleucine and phenylalanine, the nucleoside inosine, and the sugars glucose and maltose emerged as potential bioindicators of exposure to C 60 nanoparticles. The significant responses observed in earthworms using NMR-based metabolomics after exposure to very low concentrations of C 60 nanoparticles suggests the need for further investigations to better understand and predict their sub-lethal toxicity. [ABSTRACT FROM AUTHOR]

In order to cope with changing environmental conditions, organisms require highly responsive stress mechanisms. Heavy metal stress is handled by metallothioneins (MTs), the regulation of which is evolutionary conserved in insects and vertebrates and involves the binding of metal transcription factor 1 (MTF-1) to metal responsive elements (MREs) positioned in the promoter of MT genes. However, in most invertebrate phyla, the transcriptional activation of MTs is different and the exact mechanism is still unknown. Interestingly, although MREs are typically present also in invertebrate MT gene promoters, MTF-1 is notably absent. Here we use Lumbricus rubellus , the red earthworm, to study the elusive mechanism of wMT-2 activation in control and Cd-exposed conditions. EMSA and DNase I footprinting approaches were used to pinpoint functional binding sites within the wMT-2 promoter region, which revealed that the cAMP responsive element (CRE) is a promising candidate which may act as a transcriptional activator of invertebrate MTs. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are new class of pesticides and it is very meaningful to evaluate the toxicity of guadipyr to earthworm ( Eisenia fetida ). In the present study, effects of guadipyr on reproduction, growth, catalase(CAT), superoxide dismutase (SOD), acetylcholinesterase (AChE) and DNA damage in earthworm were assessed using an artificial soil medium. Guadipyr showed low toxicity to earthworms and did not elicit an effect on earthworm reproduction or growth in artificial soils at concentrations <100 mg/kg. However, after exposure to guadipyr, the activity of SOD and CAT in earthworm increased and then decreased to control level. AChE activity decreased at day 3 at 50 and 100 mg/kg and then increased to control level. Our data indicate that guadipyr did not induce DNA damage in earthworms at concentration of <100 mg/kg. [ABSTRACT FROM AUTHOR]

Lead (Pb) and BDE209 (decabromodiphenyl ether) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impact on earthworms of exposure to the two chemicals remains almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the uptake and toxicity of Pb in the presence of BDE209 to the earthworm Eisenia fetida. The results have demonstrated that the presence of BDE209 facilitated the release of Pb into soil porewater. Compared with exposure to Pb alone, simultaneous exposure to BDE209 significantly enhanced the Pb uptake rate at the level of p <0.05, while decreased the depuration rate, ultimately resulting in a larger bioaccumulation factor (BAF) value. Additionally, BDE209 addition reduced the antioxidant enzymatic activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione-s-transferase (GST)] and total antioxidant capacity (T-AOC). The decline trend in antioxidant enzymatic activities and T-AOC might explain an increase in lipid peroxidation reflected by the observed augment in malondialdehyde (MDA) level. Moreover, a biomarker of the lysosomal membrane stability, measured by neutral red retention time (NRRT), was also investigated. The NRRT obviously declined in the joint presence of BDE209, indicating a distinct time–response relationship. The results of these observations have provided a basic understanding of the potential eco-toxicological effects of joint heavy metal and BDE209 exposure on terrestrial invertebrates in a multi-contamination context of ecosystems. [ABSTRACT FROM AUTHOR]

PFOS is a toxic, persistent environmental pollutant which is widespread worldwide. PFOS contamination has entered the food chain and is interfering with normal development in man and is neurotoxic, hepatotoxic and tumorigenic. The earthworm, Eisenia fetida is one of the organisms which can help to diagnose soil health and contamination at lower levels in the food chain. Studying the chronic effects of sub-lethal PFOS exposure in such an organism is therefore appropriate. As PFOS bioaccumulates and is not easily biodegraded, it is biomagnified up the food chain. Gene expression studies will give us information to develop biomarkers for early diagnosis of soil contamination, well before this contaminant passes up the food chain. We have carried out mRNA sequencing of control and chronically PFOS exposed E. fetida and reconstructed the transcripts in silico and identified the differentially expressed genes. Our findings suggest that PFOS up/down regulates neurodegenerative-related human homologues and can cause neuronal damage in E. fetida . This information will help to understand the links between neurodegenerative disorders and environmental pollutants such as PFOS. Furthermore, these up/down regulated genes can be used as biomarkers to detect a sub-lethal presence of PFOS in soil. Neuronal calcium sensor-2, nucleoside diphosphate kinase, polyadenylate-binding protein-1 and mitochondrial Pyruvate dehydrogenase protein-X component, could be potential biomarkers for sub lethal concentrations of PFOS. [ABSTRACT FROM AUTHOR]

This work presents the results of removing heavy metals from paper mill wastewater (PMS) sludge spiked with cow dung (CD) employing Eisenia fetida. A total of seven set-ups were prepared: CD (100 percent), PMS: CD (1:3), PMS:CD (1:2), PMS:CD (1:1), PMS (100 percent), PMS:CD (3:1) and PMS:CD (2:1) and changes in chemical parameters were observed for 60 days. Vermistabilization caused the significant decrease in the level of Cd (32–37 percent), Cr (47.3–80.9 percent), Cu (68.8–88.4 percent), and Pb (95.3–97.5 percent) and substantial increase in EC, total-N, available P and K at the end. At the end, the tissues of inoculated worms showed the high load (mg kg−1, dry biomass) of Pb (8.81–9.69), Cd (2.31–2.71), Cr (20.7–35.9) and Cu (9.94–11.6), respectively which indicated bioaccumulation of metals by worms. The PMS:CD (2:1 and/or 3:1) appeared to be suitable waste mixture in terms of high metal removal and earthworm growth rates. Bioaccumulation, as quantified using BCF, was in the order: Cd>Cr>Pb>Cu. Results suggested vermiremediation as appropriate technology for bioremediation of heavy metals from PMS. [ABSTRACT FROM AUTHOR]