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Ming Hung Wong - One of the best experts on this subject based on the ideXlab platform.

  • toxicological effects of microcystin lr on earthworm Eisenia fetida in soil
    Biology and Fertility of Soils, 2017
    Co-Authors: Yanwen Li, Lei Xiang, Haiming Zhao, Lei Chen, Hui Li, Cehui Mo, Dongmei Zhou, Ming Hung Wong
    Abstract:

    Microcystin-LR (MC-LR) is a cyclic heptapeptide toxin produced by cyanobacteria in eutrophic water. It can be transferred into soil–crop systems via irrigation and cyanobacterial paste fertilization. No studies have examined the potential toxicity of MC-LR to soil animals. Therefore, in the present study, the toxicological effects of MC-LR on earthworm (Eisenia fetida), including survival, growth, reproduction, oxidative stress, and cell viability, were investigated. The LC50 of MC-LR was 0.149 μg cm−2 at 72 h based on a filter paper test and 0.460 mg kg−1 at 14 days based on an acute soil test. MC-LR seriously affected the reproduction of earthworms. Based on hatchability, the EC50 of MC-LR was 0.268 mg kg−1, similar to environmentally relevant concentrations of microcystins. The changes in activities of superoxide dismutase, guaiacol peroxidase, catalase, and glutathione peroxidase, together with the levels of glutathione and malondialdehyde, indicated that oxidative damage and lipid peroxidation played significant roles in MC-LR toxicity. In addition, the toxicity of MC-LR in earthworms increased despite degradation of MC-LR in soil over time, possibly due to the formation of toxic metabolites of MC-LR or the bioaccumulation of MC-LR in earthworms. A reduction in the neutral red retention time along with an increase in coelomocyte apoptosis with increasing MC-LR concentrations indicated a severe damage to viability. These results suggest that environmentally relevant MC-LR concentrations in agricultural soil may cause reproductive, biochemical, and cellular toxicity to Eisenia fetida. This information can be used in ecological risk assessments on MC-LR in soil.

Claus Svendsen - One of the best experts on this subject based on the ideXlab platform.

  • toxicity of cerium oxide nanoparticles to the earthworm Eisenia fetida subtle effects
    Environmental Chemistry, 2014
    Co-Authors: Elma Lahive, D. J. Spurgeon, Kerstin Jurkschat, Benjamin J Shaw, Richard D Handy, Claus Svendsen
    Abstract:

    Environmental context This study investigates the toxicity of cerium oxide nanoparticles to earthworms, key organisms in soil ecosystems. Cerium oxide did not affect survival or reproduction of the earthworms but did exert histological changes. We conclude that current soil guidelines, based simply on metal toxicity, appear to adequately protect against cerium exposure risk, at least for earthworms. Abstract The toxicity of cerium oxide (CeO2) nanoparticles (NPs) in soils is largely unknown. This study aimed to investigate the toxicity of three different CeO2 NPs to the earthworm, Eisenia fetida, for effects on survival (at day 28) and reproduction (at day 56), as well as bioaccumulation and histopathological effects. Eisenia fetida were exposed in standard Lufa 2.2 soil to three CeO2 NPs of different size ranges (5–80nm), one larger particle (300nm) and a cerium salt (ammonium cerium nitrate) over an exposure range from 41–10000mgCekg–1. Survival and reproduction were not affected by the four CeO2 particles, even at the highest exposure concentration tested. Alternatively, 10000mgCekg–1 cerium salt affected survival and reproduction; Median lethal concentration (LC50) and effective concentration (EC50) values were 317.8 and 294.6mgCekg–1. Despite a lack of toxic effect from the different forms of CeO2 particles, there was a dose-dependent increase in cerium in the organisms at all exposure concentrations, and for all material types. Earthworms exposed to CeO2 particles had higher concentrations of total cerium compared to those exposed to ionic cerium, but without exhibiting the same toxic effect. Histological observations in earthworms exposed to the particulate forms of CeO2 did, however, show cuticle loss from the body wall and some loss of gut epithelium integrity. The data suggest that that CeO2 NPs do not affect survival or reproduction in E. fetida over the standard test period. However, there were histological changes that could indicate possible deleterious effects over longer-term exposures.

D Oughton - One of the best experts on this subject based on the ideXlab platform.

  • bioavailability of cobalt and silver nanoparticles to the earthworm Eisenia fetida
    Nanotoxicology, 2012
    Co-Authors: Claire Coutris, Emmanuel Lapied, Erik J Joner, Turid Hertelaas, D Oughton
    Abstract:

    AbstractDue to difficulties in tracing engineered nanoparticles (ENPs) in complex media, there are few data on the exposure of soil biota to ENPs. This study used neutron activated cobalt (Co NPs) and silver (Ag NPs) nanoparticles, as well as soluble cobalt and silver salts, to assess the uptake, excretion and biodistribution in the earthworm Eisenia fetida. Concentrations of cobalt in worms after four weeks exposure reached 88% and 69% of the Co ions and Co NPs concentrations in food, respectively, while corresponding values for Ag ions and Ag NPs were 2.3% and 0.4%. Both Ag ions and Ag NPs in earthworms were excreted rapidly, while only 32% of the cobalt accumulated from Co ions and Co NPs were excreted within four months. High accumulation of cobalt was found in blood and in the digestive tract. Metal characterization in the exposure medium was assessed by sequential extraction and ultrafiltration. The Co NPs showed significant dissolution and release of ions, while Ag ions and particularly Ag NPs were...

Puttaganti Vijaya - One of the best experts on this subject based on the ideXlab platform.

  • Toxicological effect of Parthenium hysterophorus and milk processing industry sludge on earthworms, Eisenia fetida
    Environmental Science and Pollution Research, 2019
    Co-Authors: Harsimran Kaur, Suman Sharma, Puttaganti Vijaya
    Abstract:

    Production of large quantities of organic waste all over the world poses major environmental and disposal problems. The present study was conducted to explore the deleterious effects of Parthenium hysterophorus and milk processing industry sludge on the health of earthworm, Eisenia fetida. Earthworms were allowed to grow in the mixture of cow dung: Parthenium hysterophorus (75:25) and cow dung:milk processing industry sludge (60:40) for 60 days. The biochemical markers viz. superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels and histological changes in earthworm’s intestine were assessed after 15, 30, 45, and 60 days of exposure. The results revealed increased MDA level, while SOD, CAT, and GPx activities showed variation in both treatments. Furthermore, histopathological changes revealed damage in the intestinal tissue in both treatments during all intervals. More severe effects were registered in P. hysterophorus treatment. Obtained results may contribute to the understanding of P. hysterophorus and milk processing industry sludge induced toxic effects on earthworms and to identify defense mechanism of Eisenia fetida.

Paul M Bertsch - One of the best experts on this subject based on the ideXlab platform.