We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Negligible effects of microplastics on animal fitness and HOC bioaccumulation in earthworm Eisenia fetida in soil
AI summary Read the abstract
Researchers exposed earthworms to polyethylene and polystyrene microplastics at concentrations up to 20 percent of soil dry weight and measured oxidative stress biomarkers. While the highest concentration caused some biochemical changes, no significant effects were observed at 10 percent or below, which covers most realistic environmental scenarios. The study also found that microplastics reduced the bioaccumulation of PAHs and PCBs in earthworm tissues, suggesting that the particles may actually limit the uptake of certain organic pollutants in soil organisms.
As one type of the most widespread and long-lasting anthropogenic contaminants, microplastics have become a global environmental concern. While numerous studies have demonstrated effects of microplastics on aquatic organisms, the potential influence on terrestrial faunas is relatively less known, even though soil is a primary recipient and sink of plastics. In this study, earthworm Eisenia fetida was exposed to different levels (0, 1, 5, 10, and 20% d.w.) of polyethylene (PE, ≤300 μm) and polystyrene (PS, ≤250 μm) particles in an agricultural soil to evaluate the oxidative stress. Fluorescence imaging, after dying with Nile Red, clearly indicated the ingestion of PE and PS particles by E. fetida. Exposure to PE or PS particles at the highest rate (20%) for 14 d significantly (p < 0.05) increased the activity of catalase and peroxidase and the level of lipid peroxidation, while inhibited the activity of superoxide dismutase and glutathione S-transferase in E. fetida. However, no discernible effect was detected at amendment rates ≤10% for the majority of biochemical endpoints, suggesting that microplastic-induced oxidative stress would not occur in E. fetida under most environmental conditions. The influence of microplastics on bioaccumulation of PAHs and PCBs was also evaluated in E. fetida exposed to different levels (0, 0.1, 1, 5, and 10% d.w.) of PE and PS particles. The tissue concentrations of PAHs and PCBs were reduced in the presence of microplastics at amendment rates ≥1%, suggesting that microplastics did not act as a carrier to enhance contaminant uptake. This was attributed to competitive sorption of microplastics for contaminants and the specific feeding behavior of earthworm. Biodynamic model analysis confirmed that ingestion of microplastics contributed negligibly to contaminant bioaccumulation. Findings of this study suggested that under environmentally relevant conditions, microplastics should not cause significant toxic effects to E. fetida, nor enhance its accumulation of hydrophobic contaminants.
More Papers Like This
Understanding the harmful effects of polyethylene microplastics on Eisenia fetida: A toxicological evaluation
AI summary Read the abstract
Earthworms (Eisenia fetida) exposed to increasing concentrations of polyethylene microplastics in soil showed lower body weight, reduced reproductive output, and disrupted antioxidant defenses — with oxidative stress markers climbing nearly 1.3-fold at the highest dose. These findings confirm that microplastic pollution degrades soil ecosystem health at concentrations that could plausibly occur in contaminated agricultural land.
Oxidative stress, energy metabolism and molecular responses of earthworms (Eisenia fetida) exposed to low-density polyethylene microplastics
AI summary Read the abstract
Researchers exposed earthworms to various concentrations of low-density polyethylene microplastics for 28 days and measured oxidative stress, energy metabolism, and molecular responses. The study found dose-dependent increases in oxidative damage markers and alterations in energy reserves, suggesting that microplastic contamination in soils can trigger measurable physiological stress in soil invertebrates.
Effects of polyethylene microplastics stress on soil physicochemical properties mediated by earthworm Eisenia fetida
AI summary Read the abstract
Researchers exposed earthworms to polyethylene microplastics of two sizes and found that smaller particles (13 micrometers) were more toxic than larger ones (130 micrometers), reducing survival and growth more severely. The microplastics caused oxidative stress in the worms and altered key soil properties including pH and organic carbon content. Since earthworms play a vital role in maintaining healthy soil for agriculture, this damage could affect soil quality and ultimately the food grown in microplastic-contaminated farmland.
Toxicological effects of polystyrene microplastics on earthworm (Eisenia fetida)
AI summary Read the abstract
Researchers exposed earthworms to two sizes of polystyrene microplastics in soil for 14 days and found evidence of intestinal cell damage, oxidative stress, and DNA damage. The larger particles accumulated more in earthworm intestines, while both sizes triggered changes in key antioxidant markers. The study demonstrates that microplastic contamination in soil can cause measurable biological harm to important soil organisms.
Effects of polystyrene microplastics on the fitness of earthworms in an agricultural soil
AI summary Read the abstract
Researchers exposed earthworms to polystyrene microplastics in agricultural soil at various concentrations. The study found that low concentrations had little effect, but high concentrations (1% and above) significantly inhibited growth and increased mortality, suggesting microplastic pollution poses ecological risks to soil organisms in terrestrial ecosystems.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.