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PubMed2004

Avoidance tests with Collembola and earthworms as early screening tools for site-specific assessment of polluted soils.

Avoidance tests with earthworms and collembolans were conducted to demonstrate their feasibility as early screening tools for assessing the toxic potential of metal-polluted soils. Four different soils, with different degrees of metal contamination, were obtained from an abandoned mining area. All possible paired combinations were assessed for an avoidance response by the organisms. Data revealed that both species were able to avoid the most contaminated soils at the center of the ore extraction and treatment areas compared to those collected further away from the mine. However, earthworms and springtails differed in sensitivity to metals, especially when testing the two most polluted soils that had different contamination profiles. Earthworms exhibited a more consistent, less variable response than springtails. Overall results showed that avoidance tests with collembolans and earthworms have the potential to be used as screening tools in ecological risk assessment schemes for contaminated land, to trigger other tests in case of concern. However, further method development is needed to reduce variability in the data, particularly in the Collembola assays, and to gain knowledge about the possible effects of soil properties on the outcome of the tests.

Animals↗

PubMed2005

Earthworm toxicity during chemical oxidation of diesel-contaminated sand.

An ecotoxicity test with Eisenia fetida was performed to monitor the removal of diesel and toxicity variation during the ozonation process. The three-dimensional (3-D) cell test was introduced for the monitoring of the ozonation process, and the removal rate based on total petroleum hydrocarbons (TPHs) mass was about 95% near the ozone inlet ports. This high removal rate might be caused by the low soil organic matter (SOM) content and low water content of sand. The use of a fiber-optic transflection dip probe (FOTDP) demonstrated that more than half of the injected ozone was consumed by reactions with diesel or natural ozone-consuming materials. The earthworm toxicity test using Eisenia fetida demonstrated that diesel concentrations in soil exceeding 10,000 mg/kg caused a dose-dependent weight loss in earthworms and increased mortality. Toxic effects were reduced greatly or eliminated after ozonation, and the degradation products of the ozonation were not toxic to the earthworms at the concentrations tested. One specific result was that the sublethal test on the earthworm might be more sensitive for the evaluation of the quality of contaminated soil, for some samples, which did not result in mortality and produced an adverse effect on weight.

Animals↗

PubMed2006

Effect of soil properties on lead bioavailability and toxicity to earthworms.

Soil properties are important factors modifying metal bioavailability to ecological receptors. Twenty-one soils with a wide range of soil properties (USA; http://soils.usda.gov/technical/classification/taxonomy/) were amended with a single concentration of Pb (2,000 mg/kg) to determine the effects of soil properties on Pb bioavailability and toxicity to earthworms. Earthworm mortality ranged from 0 to 100% acute mortality following exposure to the same total concentration of Pb (2,000 mg/kg) in amended field soils. Internal Pb concentrations in earthworms ranged from 28.7 to 782 mg/kg, with a mean of 271 mg/kg. Path analysis was used to partition correlations in an attempt to discern the relative contribution of each soil property. Results of path analysis indicated that pH was the most important soil property affecting earthworm mortality (p < 0.01) and internal Pb (p < 0.05). Soil pH was related inversely to mortality and internal Pb, soil solution Pb, and Pb bioavailability. The most important soil property modifying reproduction was amorphous iron and aluminum oxides (FEAL). Because FEAL is rich in pH-dependent cation-exchange sites, several soil properties, including pH, FEAL, and cation-exchange capacity, have a causal effect on Pb adsorption and soluble Pb. Path analysis is useful for assessing contaminated soils with a wide range of soil properties and can assist in ecological risk assessment and remediation decisions for contaminated sites. Soil properties are important factors modifying metal bioavailability and toxicity and should be considered during the ecological risk assessment of metals in contaminated soils.

Animals↗

PubMed2006

Effect of pH on metal speciation and resulting metal uptake and toxicity for earthworms.

In the present study, relationships between changes in the solubility and speciation of metals in contaminated soils under different pH regimes and their toxicity to earthworms were investigated. Earthworms (Lumbricus rubellus) were exposed in a laboratory bioassay to metalliferous soils under three pH regimes: Unamended pH, pH lowered by one unit (pH -1), and pH increased by one unit (pH +1). In each soil, total (hot nitric acid-extractable) and 0.01 M CaCl2-extractable metal concentrations were measured and soil pore-water chemistry analyzed to allow metal speciation to be modeled using the Windermere Humic Aqueous Model. Earthworm metal accumulation was determined and toxicity assessed by measuring survival and reproduction and at the molecular level by recording expression of the gene encoding metallothionein-2 (MT-2) using quantitative reverse transcriptase-polymerase chain reaction. Both metal solubility and speciation were found to be highly pH dependent. Metal accumulation in earthworms was influenced by soil concentration and, in some cases (e.g., Cd), by pH. Reproduction was affected (reduced up to 90%) by soil metal level, pH, and their interaction. Relationships between analyzed and calculated Zn concentrations and toxicity and between analyzed and calculated Cd concentrations and tissue accumulation and MT-2 expression were compared by fitting dose-response models and assessing the fit of the data. This analysis indicated that values based on a pH-adjusted free ion concentration best explained toxicity (r2 = 0.82) and accumulation (r2 = 0.54). Expression of MT-2 was, however, poorly correlated (p > 0.05) with all analyzed and modeled soil metal concentrations.

Animals↗

PubMed2006

Population growth and development of the earthworm Lumbricus rubellus in a polluted field soil: possible consequences for the godwit (Limosa limosa).

Many soils are polluted with mixtures of moderate levels of contaminants. In The Netherlands 175,000 sites in rural areas are classified as highly polluted. However, it remains unclear to what extent local ecosystems are endangered. In this paper, we report on the effect of contaminants on earthworms in a meadow system. We tested a polluted and a reference field soil with similar soil characteristics and agricultural use. In the polluted soil copper, mercury, and lead were elevated by more than 200% compared with the reference soil. Bioassays on growth and reproduction in the earthworm species Lumbricus rubellus were executed in both soils, and a population model was used to assess the population-level consequences of changes in growth and reproduction. No significant effects were seen on reproduction and survival in L. rubellus, but development was retarded in the polluted soil. This resulted in a 23% lower growth rate and a change in demography toward younger individuals. Field data on population composition of earthworms were used to support the laboratory results, and the relevance of the results for the godwit (Limosa limosa), which mainly feeds on earthworms during the breeding season, is discussed.

Animals↗

PubMed2001

Cadmium uptake by earthworms as related to the availability in the soil and the intestine.

The free metal concentration in the soil solution is often considered a key parameter for metal uptake by and toxicity to soft-bodied soil organisms. The equilibrium partitioning theory, which assumes a relationship between the contaminant concentration in pore water and the contaminant concentration in the body tissue, can be used to describe uptake by earthworms. This theory has proved useful for organic chemicals, but its applicability is less clear for metals. In this study, the Cd concentration in soil pore water (pw) was varied by increasing the soil pH by the addition of lime (Ca(OH)2) and by adding manganese oxide (MnO2), which has a high metal binding capacity. Both lime (0.135% w/w) and MnO2 (1% w/w) decreased [Cd2+]pw by a factor of 25, while Cdworm was reduced only by a factor of 1.3 in lime-treated soils and 2.5 in MnO2-treated soils. Cadmium uptake was weakly related to the free metal concentration (R2adj = 0.66). Adding pH as an explanatory variable increased R2adj to 0.89, indicating that Cd uptake from pore water is pH dependent, which might be attributed to competition of protons and Cd at the surface of the earthwororm body. However, previous earthworm experiments in reconstituted groundwater showed a conspicuously smaller pH dependency of Cd uptake. The differences in metal uptake between earthworms in lime- and MnO2-treated soils are therefore more likely to reflect the predominance of pH-independent intestinal uptake of Cd. Equilibrating the soil with a solution of 0.01 M CaCl2 and 0.1 M triethanolamine (buffered at pH 7.2), simulating the conditions prevailing in the worm intestine, yielded free Cd concentrations that were closely (R2adj = 0.83) and linearly related to the Cd concentration in the earthworm tissue.

Animals↗

PubMed2001

A comparison of biomarker responses in the earthworm Aporrectodea caliginosa to the organophosphorus insecticides diazinon and chlorpyrifos.

Three biomarkers in Aporrectodea caliginosa Savigny were evaluated for their ability to detect exposure to organophosphorus insecticides, and these physiological responses were related to effects on growth and life-table parameters. Adult and juvenile earthworms were exposed to a laboratory-simulated field rate (low concentration) and a higher sublethal concentration of diazinon and chlorpyrifos. After a four-week exposure, juveniles were evaluated for cholinesterase activity, glutathione S-transferase activity, and growth, and adults were evaluated for the lysosomal neutral red retention assay (NRRA) and growth. Cholinesterase activity and the NRRA were more sensitive than growth in each age group for detecting exposure to the pesticides. Life-table parameters were evaluated in earthworms exposed as juveniles and as adults. Maturation was less sensitive to pesticides than was cocoon production. Growth and cocoon production in earthworms exposed as juveniles appeared to be more sensitive to organophosphorus insecticides than earthworms exposed as adults. Life-table responses in juveniles may, therefore, be more predictive of long-term impacts of organophosphorus insecticide applications on populations than responses in adults. Biomarker responses occurred at similar or lower concentrations than those causing an adverse effect on cocoon production and cocoon viability, indicating their usefulness in risk assessment for predicting ecologically relevant assessment end points.

Age Factors↗

PubMedDate not supplied

[Environmental activity of earthworms (Lumbricus terrestris L.) and the spatial organization of soil communities].

The effect of feeding and burrowing activities of anecic earthworms (Lumbricus terrestris) on abiotic characteristics of the soil, biomass and activity of soil microorganisms, and the spatial distribution of Collembola and Lumbricidae species was studied in a Iinden forest near Moscow. The results showed that organic carbon content, nitrogen content, pH, and microbial biomass and basal respiration are considerably higher around L. terrestris burrows than in the surrounding soil. The total density of springtails near the burrows was 1.6-1.7 as high as at the control sites. The most pronounced preference for earthworm burrows was observed in the species dominating in the soils of undisturbed deciduous forests (Isotomiella minor and Isotoma notabilis). The number and biomass of epigeic and endogeic earthworms also increased significantly in the zone of L. terrestris burrows. However, some springtail (Isotoma viridis, Protaphorura cf. nemorata, Lepidocyrtus lignorum) and earthworm species (Aporrectodea rosea) did not accumulate near L. terrestris burrows and even avoided them. Thus, L. terrestris activities create a mosaic of soil microhabitats, which provides for the coexistence of different microcommunities of soil organisms.

Animals↗

PubMed2001

[Relationship between production input and secondary succession of earthworm population in salinity transforming region of north China--a case study in Quzhou County].

The analysis on earthworm diversity in the farmland ecosystem of salinity transforming region in Quzhou County, Hebei Province, showed that the secondary succession of earthworm population had a close relationship with the input of fertilizer and manure. An optimum input, especially manure input, could accelerate the secondary succession. The general trend of earthworm distribution was in the order of second experimental district > first experimental district > third experimental district > original area. The distribution, biomass and amount of earthworm varied in different types of land-use, and the relationship was in the order of vegetable field > crop field > orchard and margin land.

Animals↗

PubMed2002

Changes in toxicity and bioavailability of lead in contaminated soils to the earthworm Eisenia fetida (Savigny 1826) after bone meal amendments to the soil.

The effect of bone meal (Ca5(PO4)3OH) amendments on lead (Pb) bioavailability to Eisenia fetida (Savigny 1826) was investigated. A standard uncontaminated soil was amended with Pb(NO3)2 solution to give Pb concentrations of 7,000 microg/g of soil. After one week, bone meal was added to one half of the soil in the ratio 1:20 bone meal:soil. Immediately after addition of the bone meal, survival times of E. fetida were 23 and 41 h in the bone meal-free and bone meal-amended soil, respectively. Twenty-eight days after addition of the bone meal, survival times of Eisenia fetida were 67 h in the bone meal-free soil and more than 168 h in the bone meal-amended soil. In a second experiment, a standard Organisation for Economic Co-operation and Development reproduction toxicity test was carried out, but in addition to Pb(NO3)2 solution, bone meal was added to the soil in the ratio 1:20 bone meal:soil. The bone meal-free soil was left for five weeks before addition of E. fetida. In the bone meal-amended soil, bone meal was added to the soil one week after addition of the Pb. The soil was left for a further four weeks before addition of Eisenia fetida. Calculated toxicities were significantly lower for the bone meal-amended soil than those calculated for the bone meal-free soil. Twenty-eight-day median lethal concentrations (LC50s; concentration that is statistically likely to kill 50% of the exposed test organism within a given time period +/- 95% confidence intervals) of Pb were 4,379 +/- 356 microg/g of soil for bone meal-free soil and 5,203 +/- 401 microg/g of soil for bone meal-amended soil. Twenty-eight-day median effect concentrations (EC50s; concentration causing a reduction by 50% of a stated parameter) of Pb for weight change were 1,408 +/- 198 microg/g of soil for bone meal-free soil and 3,334 +/- 731 microg/g of soil for bone meal-amended soil and EC50s for cocoon production were 971 +/- 633 microg/g of soil for bone meal-free soil and 1,814 +/- 613 microg/g of soil for bone meal-amended soil. Significant mortalities occurred at Pb concentrations of 2,000 microg/g of soil in the bone meal-free soil and 5,000 microg/g of soil in the bone meal-amended soil. Earthworm Pb body load was lower in the bone meal-treated soil than in the bone meal-free soil up to a Pb concentration of 5,000 microg/g of soil. Earthworm Pb body load was approximately 100 microg/g of worm in surviving earthworms in both experiments when significant mortality occurred. Water and diethylenetriamine pentaacetic acid-extractable soil Pb showed good correlations with earthworm Pb body load. These extractions could be used as estimates for Pb bioavailability.

Animals↗

PubMed2003

Availability of polycyclic aromatic hydrocarbons to earthworms (Eisenia andrei, Oligochaeta) in field-polluted soils and soil-sediment mixtures.

The bioavailability of polycyclic aromatic hydrocarbons (PAHs) for earthworms (Eisenia andrei) was experimentally determined in seven field-polluted soils and 15 soil-sediment mixtures. The pore-water concentration of most PAHs was higher than predicted. However, most of the compound was associated with dissolved organic carbon (DOC) and not directly available for uptake by earthworms. The apparent sorption could be reasonably predicted on the basis of interactions with DOC; however, the biota-soil accumulation factors (BSAFs) for earthworms were up to two orders of magnitude lower than predicted by equilibrium partitioning. The large variability between sites was not fully explained by differences in sorption. Experimental results indicate that the pool of freely dissolved PAHs in the pore water became partially depleted because of uptake by the earthworms and that bioaccumulation is thus also influenced by the kinetics of PAH desorption and mass transport. A pilot study with Lumbricus rubellus showed that steady-state body residues were well correlated to E. andrei. Current results show that depositing dredge spoil on land may lead to increased bioavailability of the lower-molecular-weight PAHs. However, risk assessment can conservatively rely on equilibrium partitioning, but accurate prediction requires quantification of the kinetics of bioavailability.

Animals↗

PubMedDate not supplied

Multivariate metabolic profiling using 1H nuclear magnetic resonance spectroscopy of freeze-tolerant and freeze-intolerant earthworms exposed to frost.

Individuals of the freeze-tolerant earthworm, Dendrobaena octaedra, and four freeze-intolerant earthworm species (Dendrodrilus rubidus, Aporrectodea icterica, A. caliginosa, and A. longa) were frozen at -2 degree C. Control earthworms were exposed to +2 degree C. 1H nuclear magnetic resonance spectroscopy-based metabolic profiling in combination with multivariate pattern recognition methods (metabonomics) was used to produce a cross-species comparison. Several biochemical changes were detected as a result of freezing in all worm species, including an increase in relative free alanine concentrations, and an apparent conversion of adenosine to inosine. It was also possible to determine a number of biochemical changes that were unique to the freeze-tolerant species, D. octaedra. The most obvious difference was that, although all species showed an increase in glucose concentrations, the increase was largest in D. octaedra, and was coupled with a concomitant decrease in glycogen. This confirms that--like previously studied freeze-tolerant earthworm species--tolerance is effected by rapid glucose production from glycogen reserves. An additional difference noted was that succinate increased in all species on freezing, but the increase was least in D. octaedra. Furthermore there was no lactate accumulation in D. octaedra, whereas three of the other four species accumulated lactate. This indicates that anoxic metabolism was lowest in the freeze-tolerant species.

Animals↗

PubMed2005

Bioaccumulation of organic chemicals in contaminated soils: evaluation of bioassays with earthworms.

Earthworms live in close contact with the soil and can thus be considered representative for the bioavailability of chemicals at contaminated sites. Bioavailability can either be assessed by analyzing earthworms from contaminated locations or by exposing laboratory-reared specimens to soil samples from the field (bioassays). In this study, we investigate the relevance of bioassays by using an extended experimental design (to identify signs of depletion of the bioavailable phase by the earthworms) and by using two species of earthworm (the standard test species Eisenia andrei and the field-relevant Aporrectodea caliginosa). Furthermore, bioassay results are compared to body residues of worms collected from the field site: a heavily polluted polder, amended with dredge spoil. We focused on telodrin, dieldrin, hexachlorobenzene, and eight PCBs. With our bioassay design, it was shown that depletion was unlikely, although more subtle effects could have occurred (e.g., changes in sorption during the experiments). E. andrei is a good choice for bioassays because its body residues correlate well to those in A. caliginosa, as well as to those in the field-collected worms. Nevertheless, E. andrei accumulated slightly more than the other species and appeared to be more sensitive to the conditions in soil from one of our sites.

Animals↗

PubMed1991

[The pavement lining of the vessels in the earthworm (Lumbricus terrestris)].

Effect of some preparatory methods to make ready earthworm tissues for electron microscopical investigation has been studied in order to reveal structural components of the vascular wall. The method for an immediate fixation of the earthworm tissues in liquid nitrogen with a subsequent additional fixation in cooled 2.5% glutar aldehyde, applied in combination with OsO4-thiocarbohydroside-OsO4 method is optimal. This method of samples preparation gives a reliable information concerning existence of an internal--endothelial--lining in the earthworm vessels. A conclusion is made on a qualitatively new level of cell differentiation of the internal vascular lining in the earthworm, which is called phase of blast transformation of endotheliocytes.

Animals↗

PubMed2006

[Effects of methamidophos and copper on ecological detoxification of acetochlor by earthworm in phaeozem].

By using microcosm culture method, this paper studied the dynamic changes of acetochlor degradation by earthworm in phaeozem with methamidophos or copper addition, aimed to approach the feasibility of using earthworm to intensify the detoxification of acetochlor. The results showed that the dynamics of acetochlor degradation accorded with the first-order reaction kinetics, whether earthworm existed or not. The activities of earthworm accelerated the detoxification of acetochlor, and the coexistence of methamidophos or copper with acetochlor evidently inhibited the degradation of acetochlor. The coexistence of methamidophos and acetochlor or of copper and higher concentration acetochlor altered the dynamics of acetochlor degradation, while the coexistence of copper and lower concentration acetochlor didn't have any obvious effect on the detoxification of acetochlor.

Animals↗

PubMed1987

Field experiment on the ability of earthworms (Lumbricidae) to reduce the transmission of infective larvae of Cooperia oncophora (Trichostrongylidae) from cow pats to grass.

In Denmark earthworms play an important role in the disappearance of cow pats on pastures. Field investigations were designed to study the influence of earthworms on the transmission of infective Cooperia oncophora larvae from experimental cow pats to grass. Results from the present experiment showed that cow pats, protected from attack by earthworms, disappeared at a much lower rate than unprotected cow pats. Development in faeces and transmission to grass of C. oncophora larvae were disturbed by the disintegration of cow pats. The rapid disintegration of unprotected cow pats resulted in an approximately 50% reduction of infective C. oncophora larvae on grass in the vicinity of these cow pats, as compared with larval contamination of grass around protected cow pats. How earthworms may cause a reduction in the transmission of infective C. oncophora larvae to grass by creating adverse conditions for the survival of parasite larvae in the cow pats, by eating and killing the parasite larvae, and by depositing parasite larvae in the soil is discussed.

Animals↗

PubMed1982

Agglutinins and proteins in the earthworm, Lumbricus terrestris, before and after injection of erythrocytes, carbohydrates, and other materials.

Agglutinin activity and total protein concentration in earthworm coelomic fluid were determined 24 hours after injecting different erythrocyte types and carbohydrates. Agglutinin titers increased from 14 to 1216 after a single injection of erythrocytes. At the same time, protein concentrations increased by variable amounts, suggesting an indirect correlation between increased agglutinin titer and protein concentration. To understand the nature of erythrocyte determinants responsible for inducing agglutinins and other proteins, separate groups of earthworms were injected with different carbohydrates. At 24 hours, coelomic fluid was assayed for agglutinin titer and protein concentration. The injection of different carbohydrates, amino acids, nucleotides and protein (BSA), like erythrocytes, also increased protein concentration and agglutinin titers. Changes in the protein concentration and composition of coelomic fluid were studied by standard and bidimensional immunoelectrophoresis. Different patterns and numbers of components were found before and after injection. At least two different components were present after injecting carbohydrates or erythrocytes, which may be related specifically to the agglutinins. Clearly, earthworms can synthesize and shed these molecules at rapid rates into the coelomic fluid. These molecules may be involved in earthworm defense.

Agglutinins↗

PubMed1996

Earthworm coelomocytes in vitro: cellular features and "granuloma" formation during cytotoxic activity against the mammalian tumor cell target K562.

Earthworms possess specific, adaptive, cellular immunodefense as well as non-specific responses found in other complex metazoans. Here we characterized coelomocytes from the earthworm Eisenia foetida by electron microscopy and cytofluorimetric analyses, and investigated structural changes that occur when effector coelomocytes and target K562 erythromyeloid human tumor cells interact during cytotoxic activity. In in vitro cultures 1) the two earthworm cell types (i.e. small and large coelomocytes) retained their morphological features; 2) their DNA content was significantly less than that of human lymphocytes and the erythromyeloid human tumor cell line K562; 3) significant percentages of coelomocytes were found to be in S or G2/M phases of the cell cycle. When cultivated alone for up to 3 h, coelomocytes formed no aggregates. However, when mixed with K562, coelomocytes spontaneously killed tumor cells, and cytotoxic reactivity was accompanied by the formation of multiple aggregates similar to granulomas. These results are the first to describe this type of earthworm non-specific "inflammatory" response in vitro against tumor cells.

Animals↗