Bioaccumulation of trace metals in the plastisphere: Awareness of environmental risk from a European perspective.

The term "Plastisphere" refers to the biofilm layer naturally formed by microorganisms attaching to plastic surfaces. This layer possesses the capability to adsorb persistent organic and inorganic pollutants, particularly trace metals, which are the focus of this research study. Immersion experiments were concurrently conducted in five locations spanning four European countries (France, Ireland, Spain, and Italy) utilising eight distinct polymers. These immersions, repeated every three months over a one-year period, aimed to evaluate the baseline bioaccumulation of 12 trace metals. The study underscores the intricate nature of metal bioaccumulation, influenced by both micro-scale factors (such as polymer composition) and macro-scale factors (including geographical site and seasonal variations). Villefranche Bay in France exhibited the lowest metals bioaccumulation, whereas Naples in Italy emerged as the site where bioaccumulation was often the highest for the considered metals. Environmental risk assessment was also conducted in the study. The lightweight nature of certain plastics allows them to be transported across significant distances in the ocean. Consequently, evaluating trace metal concentrations in the plastisphere is imperative for assessing potential environmental repercussions that plastics, along with their associated biota, may exert even in locations distant from their point of emission.

Spatial monitoring of microplastics in environmental matrices from Galway Bay, Ireland.

Microplastic concentrations have been reported in a variety of environmental matrices and organisms across the world. Assessments of environmental concentrations are essential to understand trends and ensure decision-making processes that reduce environmental pressure. In this study, a combined sampling approach to surface waters, benthic sediments and biota in Galway Bay, Ireland, was carried out. Average concentrations of microplastics in surface waters were 1.42 ± 0.33 MPs m-3, in biota were 4.46 ± 0.36 MPs ind-1 and in benthic sediments were 5.60 ± 1.54 MPs kg-1. The diversity of polymers, microplastic types and colours were more abundant in surface waters and biota, when compared to benthic sediments. Integrated assessments of microplastics that follow existing monitoring programmes are essential to understand environmental trends. This work contributes to provide valuable information to descriptor 10 of the Marine Strategy Framework Directive in Ireland.

Deep Sea Microplastic Pollution Extends Out to Sediments in the Northeast Atlantic Ocean Margins.

Microplastics are ubiquitous emerging contaminants found in every habitat surveyed, building upon international databases globally. Costs and accessibility often correlate to few deep sea sediment surveys, restricting the number of stations within a given sampling area. An extensive survey of the Porcupine Seabight, Porcupine Bank, the Goban Spur, and south-western canyons resulted in identifying microplastics in deep sea sediment surface layers from 33 of the 44 stations sampled (75%), with a total of 83 particles (74 synthetic and 9 natural) recorded. No microplastic hotspots were identified, and abundances (kg d.w.-1) were not correlated with distance from land, depth, or the presence of macrolitter on the seafloor. Understanding the sources of deep sea microplastics, such as marine traffic, is crucial to developing effective mitigation strategies as well as further monitoring campaigns targeting microplastic pollution in areas with significant deep sea biodiversity such as the Porcupine Seabright.

Size dependent egestion of polyester fibres in the Dublin Bay Prawn (Nephrops norvegicus).

Microplastics (MPs) are an extensive global contaminant in the marine environment, known to be ingested by marine organisms. The presence of MPs in the commercially important marine decapod crustacean Nephrops norvegicus (Dublin Bay Prawn) has been documented for the North-East Atlantic and the Mediterranean, however, uncertainties remain about retention times of MPs in the gastrointestinal tract (GIT) of this species. This study aims to investigate the retention times of polyester MP fibres of three sizes (3, 5, and 10 mm in length) and to determine whether the egestion of MP fibres is size and time dependent. Results suggest that MP fibres of different lengths are retained for different periods of time, with larger MP fibres being retained for longer periods (e.g., minimum 96 h for 10 mm fibres). The present study also assesses for the first time, the size dependent relationship of MP fibres under controlled conditions for N. norvegicus.

Plastics, prawns, and patterns: Microplastic loadings in Nephrops norvegicus and surrounding habitat in the North East Atlantic.

The presence of microplastics (MPs), a contaminant of emerging concern, has attracted increasing attention in commercially important seafood species such as Nephrops norvegicus. This species lend themselves well as bioindicators of environmental contamination owing to their availability, spatial and depth distribution, interactions with seafloor sediment and position in the ecosystem and food chain. This study assesses the abundance of MPs in N. norvegicus and in benthic sediments across six functional units in the North East Atlantic. Assessment of the relationship between MP abundance in N. norvegicus, their biological parameters and their surrounding environment was examined. Despite the lack of statistical significance, MP abundances, size, shape, and polymer type recorded in N. norvegicus mirrored those found in the surrounding environment samples. The three main polymers identified in both organisms and sediment were polystyrene, polyamide (nylons), and polypropylene. The level of MP contamination in N. norvegicus could be related to local sources, with relatively low abundances recorded in this study for the North East Atlantic in comparison to other regional studies. Furthermore, larger organisms contained a lower abundance of MPs, demonstrating no accumulation of MPs in N. norvegicus. Based on the results of this study, data on MP ingestion could be used to study trends in the amount and composition of litter ingested by marine animals towards fulfilling requirements of descriptor 10 of the Marine Strategy Framework Directive.

Floating microplastics in a coastal embayment: A multifaceted issue.

Floating microplastic debris at the ocean's surface represents about 1% of all plastics found in the environment, with the remainder thought to be either deposited along the coast or sinks to the bottom of the ocean. This exploratory research on a coastal embayment in the Northeast Atlantic Ocean assesses floating microplastic densities and the potential influence of wind. A total of 1182 floating microplastic particles were retrieved from a total surface seawater volume of 2039.86 m3. The average microplastic density (0.56 ± 0.33 MP m-3) is based on a sample of 20 manta trawls. This study reports primary microplastics (microbeads) floating in Irish coastal waters for the first-time. Compared to similar bays in Europe, Galway Bay has a similar microplastic density range. Microplastics in surface waters are a multifaceted issue therefore, multiple types of sample collection along with associated environmental variables are recommended for coastal monitoring purposes.