Ecological pattern of microalgal communities and associated risks in coastal ecosystems.

Eukaryotic harmful and toxic microalgae, along with their derived toxins, pose significant threats to seafood safety, human health, and marine ecosystems. Here, we developed a novel full-length 18S rRNA database for harmful and toxic microalgae and combined metabarcoding with toxin analyses to investigate the ecological patterns of phytoplankton communities and the underlying mechanism of associated toxic microalgae risks. We identified 79 harmful and toxic species in Hong Kong's coastal waters, with dinoflagellates and diatoms representing the majority of toxic and harmful taxa, respectively.

Condition of coral communities in Victoria Harbour, Hong Kong as determined by mapping seascape metrics.

Victoria Harbour, located at the centre of densely populated Hong Kong, has historically suffered from significant marine pollution. In response, the Harbour Area Treatment Scheme was fully implemented by the end of 2015, effectively treating over 2 million tonnes of sewage daily from two sides of the harbour and substantially improving water quality. This study investigated coral communities in seven sites along the natural coastline and five sites along the artificial breakwater in Victoria Harbour.

The combined effects of aging polylactic acid microplastics and TCPP on the byssus genes of the mussel Mytilus coruscus.

Polylactic acid (PLA), despite its biodegradability, readily degrades into aging microplastics (MPs) in marine environments, while tris(1-chloro-2-propyl) phosphate (TCPP), a representative organophosphorus flame retardant (OPFR), emerges as a concerning marine pollutant. To evaluate their combined effects and ecological risks, mussels were exposed to PLA (both virgin and aging at 0.2 and 1 mg/L), TCPP (0.

Exploring the biodegradation of PET in mangrove soil and its intermediates by enriched bacterial consortia.

The biodegradation of Polyethylene terephthalate (PET) is important due to the environmental impact of plastic waste. This study investigates the degradation of PET films in soil microcosms, with and without mangrove plants, and with mangrove plants bioaugmented with a bacterial consortium ( sp.- GPB12 and sp.

Combined effects of polyamide microplastics and the pathogenic bacterium Vibrio parahaemolyticus on the immune parameters of Mytilus coruscus.

The thick-shelled mussel, Mytilus coruscus, plays a vital role in marine ecosystems but is vulnerable to pollutants. Polyamide microplastics (PA-MPs), such as nylon, can adsorb harmful bacteria like Vibrio parahaemolyticus, posing threats to bivalves and economic risks to aquaculture. In this study, M.

Revealing the effects of polystyrene microplastics and di(2-ethylhexyl) phthalate on mussels:An evidence chain of gill-intestine-hemolymph.

Polystyrene microplastics (PS-MPs) and di(2-ethylhexyl) phthalate (DEHP) are widespread contaminants in marine ecosystems, posing significant risks to marine life due to their toxicity and interactions with other pollutants. This study evaluates the combined effects of PS-MPs and DEHP on Mytilus coruscus, focusing on physiological and immune responses over a 30-day exposure. Results showed significant morphological changes in gill structures, including reduced lamella dimensions and thinner stromal tissue, impairing gas exchange.

Increased sulfate-reducing bacteria can drive microbial dysbiosis in bleached corals.

Aims: Coral bleaching occurs when coral colonies lose their Symbiodiniaceae partner and turn pale or white. Although this event is generally temperature-induced, there is also the possibility of holobiont microbial infection and dysbiosis. To address this issue, this study was conducted to investigate the diversity and composition of Symbiodiniaceae and bacteria in healthy and bleached colonies of Porites lutea collected from eastern Shenzhen.

Comparative analysis of biofilm bacterial communities developed on different artificial reef materials.

Aims: Artificial reefs play a vital role in restoring and creating new habitats for marine species by providing suitable substrates, especially in areas where natural substrates have been degraded or lost due to declining water quality, destructive fishing practices, and coral diseases. Artificial reef restoration aimed at coral larval settlement is gaining prominence and initially depends on the development of biofilms on reef surfaces. In this study, we hypothesized that different artificial reef materials selectively influence the composition of biofilm bacterial communities, which in turn affected coral larval settlement and the overall success of coral rehabilitation efforts.

Advanced nanobubble flotation for enhanced removal of sub-10 µm microplastics from wastewater.

Sub-10 µm microplastics (MPs) in aquatic environments pose significant ecological and health risks due to their mobility and potential to carry harmful microcontaminants. Our effluent analysis from a Hong Kong Sewage Treatment Works shows that traditional treatment often fails to effectively remove these MPs. These small-sized MPs are commonly neglected due to challenges in accurate quantification, analysis, and removal.

Typical Tire Additives in River Water: Leaching, Transformation, and Environmental Risk Assessment.

Tire wear particles (TWPs) released during vehicle driving can enter water bodies, leading to leaching of tire additives (TAs) in aquatic environments. However, the transformation behavior and related ecological impacts of TAs and their transformation products (TPs) remain unclear. In this study, laboratory-based simulation experiments and field investigations were conducted to explore the transformation mechanisms and ecological risks of TAs.

Characterization and ecological risks of microplastics in urban road runoff.

Microplastics (MPs) deposited on urban roads are often flushed into water bodies via drainage systems without treatment, and MP concentrations in the initial road runoff may be particularly high. Yet, there is only a limited understanding of the characteristics, dynamics, and impacts of MPs in urban road runoff. In this study, stormwater and rainwater samples were collected from seven different locations in Hong Kong across 11 rainfall events between February 2021 and September 2022.

Polyamide microplastics can mitigate the effects of pathogenic bacterium on the health of marine mussels.

Vibrio parahaemolyticus and microplastics are prevalent in the ocean. Bacteria attach onto plastic particles, forming harmful biofilms that collectively threaten bivalve health. This study investigates the interaction between polyamide microplastics (PA: particle size 38 ± 12 µm) and V.

Development of a multiple-biomarker approach using the green-lipped mussel Perna viridis for marine pollution monitoring: a case study in Victoria Harbour, Hong Kong.

Pollutants often exist as mixtures in environmental settings, creating a challenge in selecting the most effective combination of biomarkers for routine monitoring. This study was conducted seasonally in Victoria Harbour, Hong Kong, to compare the responses of nine biomarkers in the green-lipped mussel Perna viridis with respect to its tissue levels of persistent organic pollutants and heavy metals. Multivariate statistical techniques were utilised to determine the single best predictor and optimal subset of biomarkers in P.

Physiological responses of the microalga Isochrysis galbana exposed to polystyrene microplastics with different particle sizes.

Due to continuous increase in marine plastic waste, microplastics are ubiquitous in the marine environment. However, there are few studies on the harmful effects caused by microplastics with different particle sizes, and the interaction between particle size and concentration requires further investigation. This study explored the differences in physiological and biochemical responses, photosynthesis and oxidative stress damage of the microalga Isochrysis galbana exposed to three different particle size microplastics.

Distribution and risk assessment of microplastics in water, sediment and brine shrimps in a remote salt lake on the Tibetan Plateau, China.

Microplastics (MPs) are pervasive environmental contaminants that have infiltrated even the most remote ecosystems. Despite their widespread distribution, the transfer patterns and impacts of MPs in remote lakes remain poorly understood. This study aimed to address the knowledge gap regarding the pathways and consequences of MP pollution in these isolated environments.

Size-dependent deleterious effects of nano- and microplastics on sperm motility.

Introduction: Growing concerns regarding the reproductive toxicity associated with daily life exposure to micro-/nano-plastics (abbreviated as MNPs) have become increasingly prevalent. In reality, MNPs exposure involves a heterogeneous mixture of MNPs of different sizes rather than a single size.

Methods: In this study, an oral exposure mouse model was used to evaluate the effects of MNPs of four size ranges: 25-30 nm, 1-5 µm, 20-27 µm, and 125-150 µm.

Physiological response of mussel to rayon microfibers and PCB's exposure: Overlooked semi-synthetic micropollutant?

Rayon microfibers, micro-sized semi-synthetic polymers derived from cellulose, have been frequently detected and reported as "micropollutants" in marine environments. However, there has been limited research on their ecotoxicity and combined effects with persistent organic pollutants (POPs). To address these knowledge gaps, thick-shell mussels (Mytilus coruscus) were exposed to rayon microfibers at 1000 pieces/L, along with polychlorinated biphenyls (PCBs) at 100 and 1000 ng/L for 14 days, followed by a 7-day recovery period.

Impact of hypoxia on glucose metabolism and hypoxia signaling pathways in juvenile horseshoe crabs Tachypleus tridentatus.

Marine hypoxia poses a significant challenge in the contemporary marine environment. The horseshoe crab, an ancient benthic marine organism, is confronted with the potential threat of species extinction due to hypoxia, making it an ideal candidate for studying hypoxia tolerance mechanisms. In this experiment, juvenile Tachypleus tridentatus were subjected to a 21-day trial at DO:2 mg/L (hypoxia) and DO:6 mg/L conditions.

Pharmaceutical Residues in Edible Oysters along the Coasts of the East and South China Seas and Associated Health Risks to Humans and Wildlife.

The investigation of pharmaceuticals as emerging contaminants in marine biota has been insufficient. In this study, we examined the presence of 51 pharmaceuticals in edible oysters along the coasts of the East and South China Seas. Only nine pharmaceuticals were detected.

Bioaccumulation of pollutants in the green-lipped mussel Perna viridis: Assessing pollution abatement in Victoria Harbour and its adjacent aquaculture area, Hong Kong, and the minimal human health risks from mussel consumption.

The green-lipped mussel Perna viridis was utilised for pollution biomonitoring in Victoria Harbour and its adjacent aquaculture area in Hong Kong. P. viridis was collected from a reference site and redeployed at five study sites for five weeks during the dry and wet seasons of 2019.

Combined effects of norfloxacin and polystyrene nanoparticles on the oxidative stress and gut health of the juvenile horseshoe crab Tachypleus tridentatus.

Pollution with anthropogenic contaminants including antibiotics and nanoplastics leads to gradual deterioration of the marine environment, which threatens endangered species such as the horseshoe crab Tachypleus tridentatus. We assessed the potential toxic mechanisms of an antibiotic (norfloxacin, 0, 0.5, 5 μg/L) and polystyrene nanoparticles (10 particles/L) in T.