In recent years, plastic waste has become a universally significant environmental problem. Ingestion of food and water contaminated with microplastics is the main route of human exposure. Fishery products are an important source of microplastics in the human diet. Once ingested, microplastics reach the gastrointestinal tract and can be absorbed causing oxidative stress, cytotoxicity, and translocation to other tissues. Furthermore, microplastics can release chemical substances (organic and inorganic) present in their matrix or previously absorbed from the environment and act as carriers of microorganisms. Additives present in microplastics such as polybrominated diphenyl ethers (PBDE), bisphenol A (BPA), nonylphenol (NP), octylphenol (OP), and potentially toxic elements can be harmful for humans. However, to date, the data we have are not sufficient to perform a reliable assessment of the risks to human health. Further studies on the toxicokinetics and toxicity of microplastics in humans are needed.

In fresh fish products, excessive loads of Pseudomonas can lead to their rapid spoilage. It is wise for Food Business Operators (FBOs) to consider its presence both in whole and prepared fish products. With the current study, we aimed to quantify Pseudomonas spp. in fresh fillets of Salmo salar, Gadus morhua and Pleuronectes platessa. For all three fish species, we detected loads of presumptive Pseudomonas no lower than 10⁴–10⁵ cfu/g in more than 50% of the samples. We isolated 55 strains of presumptive Pseudomonas and carried out their biochemical identification; 67.27% of the isolates were actually Pseudomonas. These data confirm that fresh fish fillets are normally contaminated with Pseudomonas spp. and the FBOs should add it as a “process hygiene criterion” according to EC Regulation n.2073/2005. Furthermore, in food hygiene, it is worth evaluating the prevalence of antimicrobial resistance. A total of 37 Pseudomonas strains were tested against 15 antimicrobials, and they all were identified as being resistant to at least one antimicrobial, mainly penicillin G, ampicillin, amoxicillin, tetracycline, erythromycin, vancomycin, clindamycin and trimethoprim. As many as 76.47% of Pseudomonas fluorescens isolates were multi-drug resistant. Our results confirm that Pseudomonas is becoming increasingly resistant to antimicrobials and thus should be continuously monitored in foods.

Artisanal fisheries in southern Chile rely heavily on the Patagonian red octopus (Enteroctopus megalocyathus) as a valuable resource, contributing significantly to local economies. This octopus species accounts for 25–40% of Chilean octopus landings. It is a merobenthic species, characterized by a semelparous life cycle and a long brooding period, and it is distributed along the Pacific and Atlantic coasts of the southern tip of South America, inhabiting holes and crevices in rocky substrates. However, this fishery faces critical challenges to both its ecological sustainability and the food safety of octopus products. The primary fishing method, using hooks, poses a risk to reproductive capacity as it can capture brooding females. Food safety concerns arise from microbial contamination during pre- and post-harvest handling, bioaccumulation of toxins from algal blooms, and the presence of heavy metals in the marine environment. While evisceration effectively reduces the risk of consuming toxins and heavy metals, inadequate hygiene practices and insufficient ice usage throughout the production chain represent significant food safety risks. Chilean fishing Law No. 18892/1989 defines artisanal fishing and establishes territorial use rights in fisheries (TURFs) to promote sustainable extraction of benthic resources. Integrating training programs on post-harvest handling, hygiene practices, and food safety measures into the TURFs framework, along with targeted investments in infrastructure and technical assistance, is crucial to ensure the long-term sustainability of the E. megalocyathus fishery, protect consumer health, and maintain the economic viability and environmental sustainability of this vital resource for local communities.

Swordfish ( Xiphias gladius ) is a large, migratory apex predator with a carnivorous diet, occupying a top position in the marine food chain. Although it is a valuable teleost pelagic fish with a significant commercial value, its gut microbiota has never been studied. The gut microbiota of 100 individuals was characterised by sequencing the V3–V4 region of the bacterial 16S rRNA gene. Gut microbiota findings were classified with consideration to diversity, taking into account their weight (10–20; 21–30; over 31 kg) and the FAO fishing areas in which they were caught (FAO 27, 34, 37.1.1 areas). Significant differences in the alpha diversity were observed among the weight categories for all metrics examined (except for the evenness index) and only by Shannon's index among the FAO fishing areas. Beta‐diversity analysis revealed no significant differences. The phylum Pseudomonadota dominated the swordfish gut microbiota, followed by Fusobacteriota. Photobacterium was the most abundant genus across all weight categories and FAO fishing areas. Smaller fishes showed a less rich and diverse gut microbiota, dominated almost exclusively by Photobacterium. Conversely, Pseudoalteromonas, Psychrobacter, Psychrilyobacter , and Cetobacterium appeared to increase in abundance with fish weight. Although Photobacterium was dominant across the different FAO fishing areas, distinctive microbial community compositions were observed: Cetobacterium was more prevalent in FAO 27, while Pseudoalteromonas was more prevalent in the other areas. Unlike the gut microbiota of other marine fish species, Vibrio and Lactobacillus were largely absent. This study represents the first metataxonomic characterisation of the gut microbiota of swordfish using next‐generation sequencing.