Effects of Polystyrene Microplastics on Behavioural Response and Histopathology of Carassius auratus

Microplastics pollution and seawater temperature rise have been the major environmental issues, threatening the survival and biodiversity of marine organisms. This study evaluated the combined effect of temperature and polystyrene microplastics (MP) on Artemia, a filter-feeding crustacean that is widely used for environmental toxicology studies. Brine shrimp Artemia franciscana were exposed to three MP concentrations (0, 0.2, and 2.0 mg/L) and three temperatures (22, 26, and 30 °C) for 14 d. In general, higher MP concentration and temperature led to a decreased survival rate and growth. Two-way ANOVA analysis indicated that the survival rate of Artemia was significantly impacted by both MP concentration and temperature (P 0.05). Growth of Artemia was significantly impacted by temperature (P<0.05), and with a significant interaction between two factors (P<0.05). Furthermore, the enzymatic activity, intestinal histological analyses, and immune gene expression were determined for Artemia reared at 30 °C with three MP concentrations (0, 0.2, and 2.0 mg/L). The results showed that 2.0 mg/L MP resulted in reduced Artemia intestinal microvilli and exfoliated epithelia cells, significantly increased acid phosphatase (ACP) activity (P<0.05) and immune-related gene ADRA1B and CREB3 expression, revealing that higher MP concentration could induce oxidative and immunological stress on Artemia at 30 °C. Overall, our study suggests that MP and temperature have combined adverse effect on Artemia, especially at relatively high temperature and polystyrene MP concentration. These findings are important to understand the potential ecological risks posed by these two factors on the organisms in marine environment.

Both microplastics and antibiotics are commonly found contaminants in aquatic ecosystems. Microplastics have the ability to absorb antibiotic pollutants in water, but the specific adsorption behavior and mechanism are not fully understood, particularly in relation to the impact of microplastics on toxicity in aquatic environments. We review the interaction, mechanism, and transport of microplastics and antibiotics in water environments, with a focus on the main physical characteristics and environmental factors affecting adsorption behavior in water. We also analyze the effects of microplastic carriers on antibiotic transport and long-distance transport in the water environment. The toxic effects of microplastics combined with antibiotics on aquatic organisms are systematically explained, as well as the effect of the adsorption behavior of microplastics on the spread of antibiotic resistance genes. Finally, the scientific knowledge gap and future research directions related to the interactions between microplastics and antibiotics in the water environment are summarized to provide basic information for preventing and treating environmental risks. Environ Toxicol Chem 2024;43:1950-1961. © 2024 SETAC.

Microplastics (MPs) have received significant attention recently. However, their influence on soil heavy metal adsorption remains unclear. The effect of polystyrene (PS) MPs on the adsorption of Pb(II) onto a loessial soil (sierozem) was studied by batch experiments in single soil (S), soil with 1 mm PS (S-PS1), and soil with 100 μm PS (S-PS100) systems. The mechanisms of Pb(II) adsorption reduction were investigated. The adsorption of Pb(II) reached equilibrium within 12 h, and the pseudo-second-order model fitted the adsorption processes best. The Langmuir adsorption model provided a better fit to the isotherms, compared to the Freundlich one. The presence of PS decreased the level of adsorption of Pb(II). Larger PS particle size, dose, and fulvic acid (FA) concentration inhibited Pb(II) adsorption onto the soil. The solution pH value showed a positive correlation with the adsorption amount. The adsorption amounts (q e) of Pb(II) in binary metal systems (Cu-Pb and Cd-Pb) were lower than those in single Pb systems, indicating the competitive adsorption among the ions. The adsorption amount presented a trend of S > S-PS100 > S-PS1. The primary mechanism on which PS reduced the adsorption of Pb(II) was the "dilution effect" of MPs. Conclusively, the presence of MPs might elevate the availability of heavy metals by reducing the soil's adsorption capacity for them and then amplifying the risk of heavy metal contamination and migration.

Microplastics pollution presents a major ecological risk to globe. The present study investigates the histopathological effects of chronic exposure to 1 µm polystyrene microplastics (PS-MPs) at 1.53 mg/L in goldfish (Carassius auratus) over 28 days. Histopathological analysis showed the considerable alterations in the gills, kidneys, and lever of it. Gills showed the epithelial lifting, fusion of secondary lamellae and lamellar aneurysms. Liver tissues exhibited the hepatocellular vacuolation, sinusoidal congestion, necrosis, and nuclear degeneration. The kidneys displayed tubular degeneration, glomerular shrinkage, haemorrhage, and necrosis. These results highlight the potential risks that microplastics pose to freshwater species by clearly demonstrating PS-MP-induced organ-specific toxicity. In this way the present study highlights the urgent need for regulatory measures to mitigate the microplastic pollution in aquatic environments.

Effects of polystyrene microplastics on the composition of the microbiome and metabolism in larval zebrafish

Effect of polystyrene microplastics on tetracycline photoconversion under simulated sunlight: Vital role of aged polystyrene

Micro plastic pollution in oceans is a growing global issue. These small plastic particles, less than 5 millimeters in size, come from broken-down larger plastics, micro beads in personal care products, and synthetic fibers from textiles. Once in marine environments, micro plastics are consumed by aquatic organisms, endangering marine ecosystems. Furthermore, micro plastics carry harmful chemicals, contributing to further contamination of marine habitats. Tackling this issue requires international cooperation, stronger regulations, and creative approaches to minimize plastic waste and promote environmental sustainability. Researching micro plastic pollution in marine environments is essential to understanding its widespread effects on ecosystems, marine organisms, and human health. Micro plastics are ubiquitous, impacting even the most isolated ocean areas. When ingested by marine life, they can cause physical damage, reproductive challenges, and disrupt food webs. Furthermore, micro plastics absorb and carry toxic chemicals, worsening environmental contamination. Studying these effects is vital for shaping effective regulations and creating solutions to reduce pollution. This research is key to protecting marine biodiversity and maintaining the long-term health and sustainability of ocean ecosystems for future generations. The study of micro plastic pollution in marine environments follows a structured approach. Researchers collect water, sediment, and biological samples from various marine zones, including coastal and deep-sea areas. These samples undergo processes like filtration, density separation, or chemical digestion to extract micro plastics. Microscopic analysis, often paired with spectroscopic techniques like Fourier Transform Infrared (FTIR) or Raman spectroscopy, is used to identify and examine micro plastic particles. Researchers also investigate how marine organisms ingest micro plastics and explore the potential bioaccumulation within food chains. The gathered data is crucial for understanding the scale, sources, and impacts of micro plastic pollution on marine ecosystems. Alternative taken as Polyethylene Terephthalate (PET), Polyvinyl Chloride (PVC), Polypropylene (PP), Polystyrene (PS), Nylon (Polyamide), Polyethylene (PE), Acrylic (PMMA), Cellulose Acetate, Biodegradable Plastics (PLA), Micro beads (Polyethylene). Evaluation preference taken as Biodegradability, Toxicity, Environmental Impact, Cost, Availability, Regulatory Compliance. In this context, Biodegradable Plastics (PLA) occupy the top position on the table, while Polystyrene (PS) is ranked at the bottom.

Aquatic ecosystems around the world are contaminated with a wide range of anthropogenic chemicals, including metals and organic pollutants, that originate from point and nonpoint sources. Many of these chemical contaminants have complex environmental cycles, are persistent and bioavailable, can be incorporated into aquatic food webs, and pose a threat to the health of wildlife and humans. Identifying appropriate sentinels that reflect bioavailability is critical to assessing and managing aquatic ecosystems impacted by contaminants. The objective of the present study is to review research on riparian spiders as sentinels of persistent and bioavailable chemical contaminants in aquatic ecosystems. Our review of the literature on riparian spiders as sentinels suggests that significant progress has been made during the last two decades of research. We identified 55 published studies conducted around the world in which riparian spiders (primarily of the families Tetragnathidae, Araneidae, Lycosidae, and Pisauridae) were used as sentinels of chemical contamination of lotic, lentic, and estuarine systems. For several contaminants, such as polychlorinated biphenyls (PCBs), Hg, and Se, it is now clear that riparian spiders are appropriate sentinels. However, many contaminants and factors that could impact chemical concentrations in riparian spiders have not been well characterized. Further study of riparian spiders and their potential role as sentinels is critical because it would allow for development of national-scale programs that utilize riparian spiders as sentinels to monitor chemical contaminants in aquatic ecosystems. A riparian spider sentinel program in the United States would be complementary to existing national sentinel programs, including those for fish and immature dragonflies. Environ Toxicol Chem 2022;41:499-514. © 2021 SETAC.

Effects of long-term alachlor exposure on hepatic antioxidant defense and detoxifying enzyme activities in crucian carp (Carassius auratus)

The effects of polystyrene microplastics on feeding, growth, and trophic upgrading of protozoan grazers

Heavy metal cations are a typical type of inorganic pollutant that has persistent distribution characteristics in aquatic environments and are easily adsorbed on carriers, posing serious threats to ecological safety and human health. Some studies have shown that the coexistence of dissolved organic matter (DOM) and microplastics (MPs) promotes the adsorption of heavy metal cations, but the mechanism of promoting the adsorption process has not been thoroughly studied. In this study, the effect of polystyrene microplastics (PSMPs) on the binding properties of Pb2+ onto humic acid (HA) in aquatic environments was investigated by spectral analysis and two-dimensional correlation (2D-COS) analysis. When PSMPs co-existed with HA, the adsorption capacity of Pb2+ increased. On the one hand, Pb2+ is directly adsorbed on HA through the mechanism of complexation reaction, ion exchange and electrostatic interaction. On the other hand, Pb2+ is first adsorbed on PSMPs by electrostatic action and indirectly adsorbed on HA in the form of PSMPs-Pb2+ owing to the interaction between HA and PSMPs, which increases the adsorption amount of Pb2+ on HA. This study is significant for studying the migration and regression of heavy metal cation contaminants when PSMPs co-exist with DOM in an aqueous environment.

Unraveling the mechanism of brain damage in Carassius auratus by polypropylene microplastics and oxytetracycline via the brain-gut-microbiota axis.

Can crayfish serve as bioindicator of environmental impact after exposure to Bisphenol A?

This study investigated the effects of dicamba (DIC), a widely used auxinic pesticide in agriculture, on carp fish as an experimental model, especially examining serum adrenocorticotropic hormone (ACTH), cortisol (CORT), growth hormone (GH), and insulin-like growth factor-1 (IGF-1) levels. Additionally, it analyzed serum tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) levels, as well as histopathological changes in gill and liver tissues. Fish were exposed to varying doses (1.35 and 13.5ppm) and durations (4 and 30days). Sixty fish were randomly assigned to six groups (10 fish/group) and exposed to the specified DIC concentrations and durations. Following exposure, stress, growth, and immune parameters were assessed, along with pathological changes. Analyses revealed dose-dependent increases in ACTH, CORT, and TNF-α levels in both exposure periods compared to controls. Conversely, decreases in GH, IGF-1, IL-1β, and IL-6 levels were observed. A significant difference (p < 0.05) was noted in the changes of ACTH, CORT, TNF-α, GH, IGF-1, IL-1β, and IL-6 levels between the exposure periods in the subchronic phase for both dose groups. Histopathological examination identified significant alterations in gill and liver tissues across all dose groups. Gill pathology included epithelial separation (aneurysm), shortening and fusion of secondary lamellae, clubbing, reduced interlamellar space, and cartilage tissue damage. Liver histopathology showed hepatocellular degeneration, passive hyperemia, mononuclear cell infiltration, and hepatocyte vacuolization. In conclusion, dicamba exposure induced significant stress, growth, immune, and histopathological changes in carp, highlighting its potential harmful effects on aquatic organisms, especially at higher concentrations and prolonged exposure durations.

Background: The pesticides are known to adversely affect the quality of water and create hazards for aquatic life that results in severe damage to non-target freshwater organisms including fish. Among them, the organophosphorus pesticide, chlorpyrifos (CPF) is one of the most commonly used pesticides for controlling various kinds of pests in agriculture. Pesticides after entering in to the body of fish bring about histopathological and biochemical changes in different target and non-target organs. Hence, the present study aimed to investigate the toxicity effects of Chlorpyrifos (CPF) and associated histopathological changes in the gill, liver and kidney of the Mozambique Tilapia, Oreochromis mossambicus under the acute toxicity concentrations. Methods: Static bioassay was carried out for Chlorpyrifos with Oreochromis mossambicus as test animal for a period of 96 hrs as per standard methods and LC50 values were calculated through Probit analysis. The fishes were exposed to five acute concentrations (0.033, 0.066, 0.132, 0.264 and 0.528 ppb). The gill, liver and kidney tissues were collected from the fishes exposed to the pesticide and standard histology protocol was followed to investigate the histopathological changes. Result: The histological changes observed in the gill included lamellar aneurysm, curling of secondary lamellae, shortening of the secondary lamellae, hypertrophy of epithelial cell, fusion of secondary lamellae, deformation of the cartilage core, blood congestion, collapsed secondary lamellae, excessive mucus secretion, disorganization of the secondary lamellae, haemorrhage at primary lamellae, necrosis, haemorrhage at secondary lamellae. The most common histopathological changes in the liver were characterized by cellular necrosis, degeneration of hepatocytes, nuclear degeneration, fat deposition, rupture of nucleus, hypertrophied hepatocytes, blood congestion, blood sinusoids, cellular hypertrophy, increased pycnotic nucleus, cirrhosis and hemosiderosis. Further, histological changes like appearance of dilated lumen, hypertrophied epithelial cells, severe haemorrhage, blood congestion, melanomacrophage aggregation, narrowing of lumen, degenerated tubule, degenerated glomerulus, shrunken glomerulus and distended glomerulus were observed in the kidney. Thus, it is evident from the present study that Chlorpyrifos can be a potential toxicant affecting the fishes at tissue level on dose and time dependent manner which are expected to affect the other physiological processes in the long run.