Spatio-temporal trends in microplastic presence in the sediments of the River Thames catchment (UK).

This study investigated the spatio-temporal variability of microplastics (MPs) in the sediments of the River Thames (UK) catchment over 30 months (July 2019 - Dec 2021). The average MP concentration was 61 items kg d.w.

Dilute concentrations of maritime fuel can modify sediment reworking activity of high-latitude marine invertebrates.

Multiple expressions of climate change, in particular warming-induced reductions in the type, extent and thickness of sea ice, are opening access and providing new viable development opportunities in high-latitude regions. Coastal margins are facing these challenges, but the vulnerability of species and ecosystems to the effects of fuel contamination associated with increased maritime traffic is largely unknown. Here, we show that low concentrations of the water-accommodated fraction of marine fuel oil, representative of a dilute fuel oil spill, can alter functionally important aspects of the behaviour of sediment-dwelling invertebrates.

Current and emerging technologies for the remediation of difficult-to-measure radionuclides at nuclear sites.

Difficult-to-measure radionuclides (DTMRs), defined by an absence of high energy gamma emissions during decay, are problematic in groundwaters at nuclear sites. DTMRs are common contaminants at many nuclear facilities, with (often) long half-lives and high radiotoxicities within the human body. Effective remediation is, therefore, essential if nuclear site end-state targets are to be met.

The distribution and enrichment of trace elements in surface and core sediments from the Changjiang River Estuary, China: Evidence for anthropogenic inputs and enhanced availability of rare earth elements (REE).

Huge amount of trace metals emitted through manmade activities are carried by the Changjiang River into the East China Sea. Most of them deposit in the Changjiang River Estuary and threaten the regional aquatic environment. In this study, major and trace elements of 34 archive surface sediments and two cores are examined.

The Searsville Lake Site (California, USA) as a candidate Global boundary Stratotype Section and Point for the Anthropocene series.

Unlabelled: Cores from Searsville Lake within Stanford University's Jasper Ridge Biological Preserve, California, USA, are examined to identify a potential GSSP for the Anthropocene: core JRBP2018-VC01B (944.5 cm-long) and tightly correlated JRBP2018-VC01A (852.5 cm-long).

Microplastic accumulation in Halophila ovalis beds in the Swan-Canning Estuary, Western Australia.

Small ephemeral seagrass (Halophila ovalis) beds in the Swan-Canning Estuary, Western Australia, were sampled to determine if microplastics attach to seagrass blades and accumulate in higher concentrations in seagrass sediment compared to bare sediment. Three microplastics were observed attached to sampled seagrass blades (n = 108). Microplastics had a mean concentration in seagrass sediments of 1000 ± 100.

Time-Integrated Bioavailability Proxy for Actinides in a Contaminated Estuary.

Actinides accumulate within aquatic biota in concentrations several orders of magnitude higher than in the seawater [the concentration factor (CF)], presenting an elevated radiological and biotoxicological risk to human consumers. CFs currently vary widely for the same radionuclide and species, which limits the accuracy of the modeled radiation dose to the public through seafood consumption. We propose that CFs will show less dispersion if calculated using a time-integrated measure of the labile (bioavailable) fraction instead of a specific spot sample of bulk water.

Role of saltmarsh systems in estuarine trapping of microplastics.

Saltmarshes are important natural ecosystems along many temperate (and other) coastlines. They stabilize sediments and act as biofilters for a range of industrial pollutants and, potentially, microplastics. Accumulation of microplastics along estuarine coastlines may be enhanced by the presence of saltmarsh species, as they offer better particle trapping efficiency than adjacent intertidal mudflats under prevailing flood and ebb tidal currents.

Bioavailable actinide fluxes to the Irish Sea from Sellafield-labelled sediments.

Nuclear discharges to the oceans have given rise to significant accumulations of radionuclides in sediments which can later remobilise back into the water column. A continuing supply of radionuclides to aquatic organisms and the human food chain can therefore exist, despite the absence of ongoing nuclear discharges. Radionuclide remobilisation from sediment is consequently a critical component of the modelled radiation dose to the public.

Environmental risk of trace metals and metalloids in estuarine sediments: An example from Southampton Water, U.K.

Industrial and commercial port activities are widely recognized worldwide as an important source of pollution to proximal estuaries. In this study, we analysed geochemical and sedimentological parameters including major and trace elements, organic matter and sediment texture in surface sediments from the estuarine environment of Southampton Water, U.K.

Developing field-scale, gentle remediation options for nuclear sites contaminated with Cs and Sr: The role of Nature-Based Solutions.

The remediation of contaminated land using plants, bacteria and fungi has been widely examined, especially in laboratory or greenhouse systems where conditions are precisely controlled. However, in real systems at the field scale conditions are much more variable and often produce different outcomes, which must be fully examined if 'gentle remediation options', or GROs, are to be more widely implemented, and their associated benefits (beyond risk-management) realized. These secondary benefits can be significant if GROs are applied correctly, and can include significant biodiversity enhancements.

Battling the known unknowns: a synoptic review of aquatic plastics research from Australia, the United Kingdom and China.

Plastic pollution is a global environmental and human health issue, with plastics now ubiquitous in the environment and biota. Despite extensive international research, key knowledge gaps ("known unknowns") remain around ecosystem-scale and human health impacts of plastics in the environment, particularly in limnetic, coastal and marine systems. Here we review aquatic plastics research in three contrasting geographic and cultural settings, selected to present a gradient of heavily urbanised (and high population density) to less urbanised (and low population density) areas: China, the United Kingdom (UK), and Australia.

Novel DGT Configurations for the Assessment of Bioavailable Plutonium, Americium, and Uranium in Marine and Freshwater Environments.

Plutonium, americium, and uranium contribute to the radioactive contamination of the environment and are risk factors for elevated radiation exposure ingestion through food or water. Due to the significant environmental inventory of these radioelements, a sampling method to accurately monitor their bioavailable concentrations in natural waters is necessary, especially since physicochemical factors can cause significant temporal fluctuations in their waterborne concentrations. To this end, we engineered novel diffusive gradients in thin-film (DGT) configurations using resin gels, which are selective for UO, Pu(IV + V), and Am(III) among an excess of extraneous cations.

"Old" and "new" contaminants and their management: learning from the past, looking to the future.

Within the 50 year lifetime of the Society for Environmental Geochemistry and Health (SEGH), we have seen a number of contaminants transfer from being the wonder chemical of their day through to becoming current contaminants of concern. This is also true for a variety of emerging contaminants such as plastic microbeads, pharmaceutical residues, and fire retardant chemicals, amongst others. This thought piece discusses the risk associated with a range of these emerging contaminants, their global nature, how existing models and frameworks can be applied to deal with their impacts, and research and management gaps and challenges.

Systematic and bibliographic review of sustainability indicators for contaminated site remediation: Comparison between China and western nations.

Sustainable remediation, which promotes the use of more sustainable practices during environmental clean-up activities, is an area of intense international development. While numerous indicators related to sustainable remediation assessment have been utilized and published in related academic literature, they are difficult to unify and vary in emphasis between countries. Following literature retrieval from CNKI, Springer, ScienceDirect, and Wiley Online databases, we present a systematic and bibliometric analysis of relevant national and international literature to define the most frequently considered indicators of sustainability, which play important roles in selecting remediation technologies or site management methods from a sustainability perspective.

Towards the application of electrokinetic remediation for nuclear site decommissioning.

Contamination encountered on nuclear sites includes radionuclides as well as a range of non-radioactive co-contaminants, often in low-permeability substrates such as concretes or clays. However, many commercial remediation techniques are ineffective in these substrates. By contrast, electrokinetic remediation (EKR), where an electric current is applied to remove contaminants from the treated media, retains high removal efficiencies in low permeability substrates.

Assessing the role of the "estuarine filter" for emerging contaminants: pharmaceuticals, perfluoroalkyl compounds and plasticisers in sediment cores from two contrasting systems in the southern U.K.

The environmental occurrence, fate and ecotoxicity of emerging contaminants (ECs) has been the subject of increasing research, policy and public concern over the past two decades. While a wide range of publications have examined the environmental persistence and sediment/soil interactions of ECs following their discharge into aquatic environments, the extent to which ECs are sequestered in estuarine sediments, and the impact of this on their environmental persistence and supply to the ocean, in comparison remains unclear. This Article examines the environmental concentrations of seven, relatively water-soluble and environmentally mobile, ECs (including pharmaceuticals, perfluoroalkyl compounds, and plasticisers) in dated intertidal saltmarsh cores from two contrasting estuarine sites in the southern U.

Validation of a method to quantify microfibres present in aquatic surface microlayers.

Many of the methods for microplastics quantification in the environment are criticised creating problems with data validity. Quantification of microplastics in the surface microlayer of aquatic environments using glass plate dipping holds promise as a simple field method, but its efficiency has yet to be validated. We tested a standard glass plate dipping method to assess recovery of four common polymer microfibres and two common natural fibres, under three different salinities (freshwater, brackish water, saltwater).

Identification of tidal trapping of microplastics in a temperate salt marsh system using sea surface microlayer sampling.

Microplastics are contaminants of increasing global environmental concern. Estuaries are a major transport pathway for land-derived plastics to the open ocean but are relatively understudied compared to coastal and open marine environments. The role of the "estuarine filter", by which the supply of sediments and contaminants to the sea is moderated by processes including vegetative trapping and particle flocculation, remains poorly defined for microplastics land to sea transfer.

Novel nanostructured iron oxide cryogels for arsenic (As(III)) removal.

Novel macroporous iron oxide nanocomposite cryogels were synthesized and assessed as arsenite (As(III)) adsorbents. The two-step synthesis method, by which a porous nanonetwork of iron oxide is firstly formed, allowed a homogeneous dispersion of the iron oxide in the cryogel reaction mixture, regardless of the nature of the co-polymer forming the cryogel structure. The cryogels showed excellent mechanical properties, especially the acrylamide-based cryogel.

Driving forces and barriers in the removal of phosphorus from water using crop residue, wood and sewage sludge derived biochars.

The removal of phosphorus (P) from sewage effluents is necessary to control eutrophication in receiving waters. Biochar has been proposed and is investigated for the capture and reuse of P, however the forces driving and limiting P adsorption are still largely unclear. To identify the forces governing P uptake by biochar, biochars with markedly different physicochemical characteristics derived from a variety of biomass (oilseed rape straw, wheat straw, miscanthus straw, rice husk, soft wood and sewage sludge residue), pyrolysed at various temperatures, were investigated.

Sediment structure and physicochemical changes following tidal inundation at a large open coast managed realignment site.

Managed realignment (MR) schemes are being implemented to compensate for the loss of intertidal saltmarsh habitats by breaching flood defences and inundating the formerly defended coastal hinterland. However, studies have shown that MR sites have lower biodiversity than anticipated, which has been linked with anoxia and poor drainage resulting from compaction and the collapse of sediment pore space caused by the site's former terrestrial land use. Despite this proposed link between biodiversity and soil structure, the evolution of the sediment sub-surface following site inundation has rarely been examined, particularly over the early stages of the terrestrial to marine or estuarine transition.

A cryogel-based bioreactor for water treatment applications.

The aim of this study was to develop and test a non-diffusion limited, high cell density bioreactor for biodegradation of various phenol derivatives. The bioreactor was obtained using a straightforward one-step preparation method using cryostructuration and direct cross-linking of bacteria into a 3D structured (sponge-like) macroporous cryogel composite material consisting of 11.6% (by mass) cells and 1.

Agricultural wastes from wheat, barley, flax and grape for the efficient removal of Cd from contaminated water.

Agricultural production results in wastes that can be re-used to improve the quality of the environment. This work has investigated for the first time the use of abundant, un-modified agricultural wastes and by-products (AWBs) from grape, wheat, barley and flax production, to reduce the concentration of Cd, a highly toxic and mobile heavy metal, in contaminated water. At concentrations of 1.

Using a conceptual site model for assessing the sustainability of brownfield regeneration for a soft reuse: A case study of Port Sunlight River Park (U.K.).

Brownfield regeneration to soft reuse such as recreation and amenity has become increasingly common due to the demand for the potential environmental, social and economic benefits that it can deliver. This has led in turn to an increased demand for improved tools to support decision-making for this style of regeneration: tools which are simple to use, based on robust scientific principles and preferably which can ultimately link to quantitative or semi-quantitative cost-benefit analyses. This work presents an approach to assessing and comparing different scenarios for brownfield regeneration to soft reuse and other end-points.