Effects of extremely high concentrations of polystyrene microplastics on asexual reproduction and nematocyst discharge in the jellyfish Sanderia malayensis

Unraveling the threat: Microplastics and nano-plastics' impact on reproductive viability across ecosystems

Plastic pollution pervades both marine and terrestrial ecosystems, fragmenting over time into microplastics (MPs) and nano-plastics (NPs). These particles infiltrate organisms via ingestion, inhalation, and dermal absorption, predominantly through the trophic interactions. This review elucidated the impacts of MPs/NPs on the reproductive viability of various species. MPs/NPs lead to reduced reproduction rates, abnormal larval development and increased mortality in aquatic invertebrates. Microplastics cause hormone secretion disorders and gonadal tissue damage in fish. In addition, the fertilization rate of eggs is reduced, and the larval deformity rate and mortality rate are increased. Male mammals exposed to MPs/NPs exhibit testicular anomalies, compromised sperm health, endocrine disturbances, oxidative stress, inflammation, and granulocyte apoptosis. In female mammals, including humans, exposure culminates in ovarian and uterine deformities, endocrine imbalances, oxidative stress, inflammation, granulosa cell apoptosis, and tissue fibrogenesis. Rodent offspring exposed to MPs experience increased mortality rates, while survivors display metabolic perturbations, reproductive anomalies, and weakened immunity. These challenges are intrinsically linked to the transgenerational conveyance of MPs. The ubiquity of MPs/NPs threatens biodiversity and, crucially, jeopardizes human reproductive health. The current findings underscore the exigency for comprehensive research and proactive interventions to ameliorate the implications of these pollutants.

Multi-dimensional visualization of ingestion, biological effects and interactions of microplastics and a representative POP in edible jellyfish

Due to their ubiquity and potential risks, microplastics (MPs) and nanoplastics (NPs) are concerning environmental issues. Yet there are still significant knowledge gaps in understanding the tissue-specific accumulation and dynamic change of MPs and NPs in the aquatic organism and how these micro/nano-scale emerging contaminants interact with other environmental pollutants such as persistent organic pollutants (POPs). Here, in vivo imaging systems (IVIS), radioisotope tracing, and histological staining were innovatively used to reveal the fate and toxicity of fluorescently-labeled MPs/NPs and 14C-labeled 2,4,4'-trichlorobiphenyl (PCB28) in edible jellyfish Rhopilema esculentum. These contaminants' ingestion, biological effects, and interactions were visualized at cellular, tissue, and whole-body multidimensional levels. Both MPs and NPs were shown to be preferentially accumulated in the mouthlets of oral arms, and most ingested MPs/NPs were present in the extracellular environment instead of being internalized into the mesoglea. Moreover, the presence of MPs or NPs in the seawater significantly inhibited the bioaccumulation of PCB28 in the jellyfish tissue, thus alleviating physiological alteration, gastric damage, and apoptosis caused by PCB28. This study provides a multi-dimensional visualization strategy to display the distribution and biological effects of typical pollutants in marine organisms and offers new insights for understanding the impacts of MPs/NPs and POPs on marine ecosystems.

Nanoplastic uptake temporarily affects the pulsing behavior in ephyrae of the moon jellyfish Aurelia sp

The aim of this study is to investigate for the first time the uptake and ecotoxicological effects of nanoplastics (NPs) in a marine cnidarian. Ephyrae of the moon jellyfish Aurelia sp. of different ages (0 and 7 days old) were exposed to negatively charged polystyrene NPs for 24 h; then, the uptake was assessed through traditional and novel techniques, namely microscopy and three-dimensional (3D) holotomography. Immobility and behavioral responses (frequency of pulsations) of ephyrae were also investigated to clarify if NP toxicity differed along the first life stages. NP uptake was observed in ephyrae thanks to the 3D technique. Such internalization did not affect survival, but it temporarily impaired the pulsation mode only in 0 day old ephyrae. This may be ascribed to the negative charged NPs, contributing to jellyfish behavioral alteration. These findings promote 3D holotomography as a suitable tool to detect NPs in marine organisms. Moreover, this study recommends the use of cnidarians of different ages to better assess NP ecotoxicological effects in these organisms, key components of the marine food web.

Assessing phytotoxicity of microplastics on aquatic plants using fluorescent microplastics

Although studies on microplastics are increasing every year, still very little is known about their toxicity. Especially for plant species, even studies of uptake of microplastics are only few, not to mention phytotoxicity of microplastics. Therefore, we conducted a pilot study on the phytotoxicity of 1-μm-sized fluorescent microplastics (FMPs) on the free-floating aquatic plants Spirodela polyrhiza and Salvinia natans and the emergent aquatic plant Phragmites australis using 0.1% and 0.01% FMP treatment. Furthermore, uptake of FMPs by plants was verified by detecting fluorescence of FMPs by laser. A free-floating aquatic plant S. polyrhiza and emergent aquatic plant P. australis showed significantly decreased harvested biomass after 3 weeks indicating phytotoxicity of FMPs, but S. natans did not show any differences of harvested biomass or chlorophyll contents among treatments. Detection of fluorescence from plant leaves provided evidence of active FMPs uptake by plants. The emission spectra of plant leaves in 0.1% FMP treatment showed similar peaks to those of free fluorescent microplastics, providing a firm evidence of FMPs uptake by plants. This study is one of the pioneering studies to explore fluorescent microplastic uptake and toxicity in aquatic plants and therefore provides a baseline for further studies.

Selective feeding protects moon jellyfish (Aurelia aurita s.l.) from overloading with microplastics

Jellyfish blooms may be important bioindicators for marine ecosystem degradation, including the accumulation of microplastics in pelagic food webs. Here we show growth, respiration and filtration rates of the moon jellyfish (Aurelia aurita s.l.) when fed high concentrations (350 L^-1) of zooplankton prey (Artemia salina nauplii) and polystyrene (PS) or reference particles (charcoal; size range 50-500 μm). Our controlled feeding experiments reveal that inedible particles are ingested less efficiently compared to prey (retention efficiency ~60 % for PS) and actively removed from the gastrovascular system of ephyrae and medusae. Increased metabolic demands for excretion of inedible material (up to 76.7 ± 3.1 % of ingested prey biomass) suggest that overloading with microplastics can decelerate growth (observed maxima 26.1 % d^-1 and 12.6 % d^-1, respectively) and reproductive rates when food is limited. Possible consequences of this selective feeding strategy in response to proceeding microplastic pollution in the world's future oceans are discussed.

A review on enhanced microplastics derived from biomedical waste during the COVID-19 pandemic with its toxicity, health risks, and biomarkers

The COVID-19 pandemic led to the explosion of biomedical waste, a global challenge to public health and the environment. Biomedical waste comprising plastic can convert into microplastics (MPs, < 5 mm) by sunlight, wave, oxidative and thermal processes, and biodegradation. MPs with additives and contaminants such as metals are also hazardous to many aquatic and terrestrial organisms, including humans. Bioaccumulation of MPs in organisms often transfers across the trophic level in the global food web. Thus, this article aims to provide a literature review on the source, quantity, and fate of biomedical waste, along with the recent surge of MPs and their adverse impact on aquatic and terrestrial organisms. MPs intake (ingestion, inhalation, and dermal contact) in humans causing various chronic diseases involving multiple organs in digestive, respiratory, and reproductive systems are surveyed, which have been reviewed barely. There is an urgent need to control and manage biomedical waste to shrink MPs pollution for reducing environmental and human health risks.

Towards robust and repeatable methods for studying interactions between jellyfish and microplastics

Studies of microplastics are increasing exponentially and standard protocols are only beginning to be established. Jellyfish are considered susceptible to ingesting microplastics because they feed on small, suspended particles. Inconsistent approaches used to study interactions between jellyfish and microplastics, however, make comparisons among studies difficult. Here we review aspects of the methods used to sample jellyfish in the field and experimental approaches used in the laboratory to study interactions between jellyfish and microplastics, recommend some standard protocols and identify areas for further research. We highlight the need for experiments to be environmentally relevant, to study a greater diversity of species and to study different life history stages.