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Radioactive 141 Ce in ionic (I-Ce), nano (N-Ce, 11 ± 9 nm mean primary particle size ± standard deviation) and micron-sized (M-Ce, 530 ± 440 µm) forms associated with natural and artificial diets in natural river water and synthetic freshwater were used to measure the real-time biokinetics of dietary 141 Ce assimilation in a freshwater food chain. The model food chain consisted of microalgae (Raphidocelis subcapitata), snails (Potamopyrgus antipodarum) and prawns (Macrobrachium australiense). Pulse-chase experiments showed that 91-100 % of all forms of cerium associated with all diets and water types were eliminated from the digestive system of the snail and prawn within 24 h, with no detectable cerium assimilation. The prawn and snail median elimination times (ET50) and elimination rates (Ke) for all cerium forms ranged from 0.05 to 1.7 d, and 30 to >100 % per d, respectively. The pulse-chase results were supported by the autoradiographic evidence for N-Ce and M-Ce that confirmed no detectable assimilation and translocation within the tissue of the prawn over time. In contrast, the more soluble I-Ce was found to be associated in low quantities with the hepatopancreas in the prawn confirming that the lack of dissolution by N-Ce and M-Ce in the digestive environment of these organisms makes these forms less bioavailable. In addition, hetero-agglomeration of N-Ce and M-Ce resulted in particles that did not dissociate in digestive fluids and were too large to be assimilated thereby making them non-bioavailable. Based on the results from this study and from the literature review, the risk of N-Ce biomagnification and chronic dietary toxicity in freshwater ecosystems is no greater than the risk associated with M-Ce or I-Ce., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lisa Golding reports financial support was provided by Australian Institute of Nuclear Science and Engineering. Co-authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Objectives: To report the injury epidemiology of the Great Britain's (GB) men's basketball team games and training over a 6-season period., Methods: Non-time loss (NTL) and time-loss (TL) injuries were recorded throughout 14 international windows (2018-2024). Exposure (player-hours) was recorded for team training and games. NTL and TL injury incidence is presented per 1000 player-hours (p/1000 h; 95% CI) for training, games and overall exposure. TL severity (days-lost) and burden (days-lost/1000 h; 95% CI) was calculated, with incidence rate ratios (IRR, 95% CI) comparing game and training incidence for each definition., Results: Throughout the study period, 113 injuries were recorded, of which 65 were GB related (43 NTL and 22 TL). Game injury incidence was significantly greater than training for TL (96/1000 h; 95% CI 33-159 versus 6/1000 h; 95% CI 2-9; IRR = 17; 95% CI 7-44) and NTL (75/1000 h; 95% CI 10-131 versus 7/1000 h; 95% CI 3-11; IRR = 11; 95% CI 4-28) injury definitions. Overall, most TL injuries occurred at the ankle (36%, 5/1000 h; 95% CI 2-9) and NTL injuries at the knee (19%, 5/1000 h; 95% CI 2-9). 31 overuse injuries were recorded, with 25% lower limb tendinopathies. TL injury severity ranged from 1 to 30 days, with injury burden for games (675/1000 h; 95% CI 234-1116) greater than training (48/1000 h; 95% CI 55-133)., Conclusion: The reported game injury incidence is high, with a large prevalence of NTL injuries. Lower limb injuries were most common, particularly overuse knee injuries. Preventative strategies need to be specific in the international basketball context, where camps are short but intense in duration.

Iodine is an essential micronutrient for human nutrition, though it is found in relatively low concentrations in many important crop species. Wheat (Triticum aestivum L.) is a common staple crop worldwide, and as such could be an important source of dietary iodine due to its widespread consumption. However, little is known about iodine concentrations in wheat grain grown under rainfed field conditions, nor the impact of growing region or environment on these concentrations. Therefore, this paper had three objectives; (1) quantify the iodine concentration in a popular variety of wheat cultivated across the wheat belt of three Australian States (Western Australia, South Australia and Victoria) over two winter seasons (2) determine the influence of distance from the coast, rainfall, elevation, soil type and pH and grain yield on wheat grain iodine concentrations and (3) identify geographical areas where iodine concentrations of wheat grains are low enough that biofortification with iodine would be advantageous for human health outcomes. We sampled iodine concentrations of a single cv. Scepter at 125 sites from the winter season 2020 (65 sites) and 2021(60 sites), to investigate environmental and geographical effects on wheat grain iodine concentrations. Iodine concentrations were measured using triple quadrupole inductively coupled plasma mass spectrometer (ICP MS/MS). We found that the elevation and the region (State) of growing sites were the most significant predictors of iodine concentration, along with the interaction between rainfall and topsoil texture. However, very low concentrations of iodine (5-24 μg/kg) were detected in all samples tested, indicating that even wheat grown under advantageous environmental and geographic conditions in southern Australia would be unlikely to represent an important source of dietary iodine. This emphasises the need to consider biofortification strategies to improve iodine concentrations in Australian grown wheat to improve the dietary uptake of this essential micronutrient by human consumers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Scoping review has identified a lack of evidence guiding long-term follow-up of elbow arthroplasty. We report the effectiveness of primary linked total elbow arthroplasty surveillance in identifying failing implants requiring revision., Methods: A prospective database recording consecutive primary linked total elbow arthroplasty and subsequent surveillance in an elbow unit was analysed. Arthroplasties performed between 01.10.2013 and 31.07.2022 were included, with a minimum 1-year follow-up. Surveillance involves specialist physiotherapist review 1, 2, 3, 5, 8 and 10 years postoperatively. Patient-initiated review could occur between time points. Outcome measures include a number of surveillance reviews offered and attended; and the proportion that identified a failing implant requiring revision., Results: Ninety-seven primary linked total elbow arthroplasties with minimum 1-year follow-up were performed (76 Discovery, 14 Nexel, 7 Coonrad/Morrey). Sixteen patients died prior to 31.07.2023, and three implants required revision <1 year postoperatively. 290 of 328 offered surveillance appointments were attended (88.4%). Five implants required revision ≥1 year post-operatively, with revision requirements identified by surveillance in all cases. Three failures occurred at 5 years postoperatively, and two failures occurred at 8 years postoperatively. Overall, 1.7% attended surveillance appointments identified a failing implant requiring revision., Discussion: This is the first series reporting the effectiveness of primary linked total elbow arthroplasty surveillance in identifying implants requiring revision., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Cadmium pollution poses a significant threat to aquatic ecosystems due to its propensity to bioaccumulate and cause toxicity. This study assessed the complex dynamics of cadmium uptake, accumulation and distribution across anuran development to provide new insights into the fate of cadmium burdens during metamorphosis and compare the susceptibility of different life stages to cadmium accumulation. Tadpoles of various developmental stages were exposed to dissolved 109-cadmium and depurated in clean water in a series of experiments. Temporal changes in whole-body and tissue concentrations were analysed using gamma spectroscopy, and anatomical distributions were visualised using autoradiography. Results showed that animals exposed at the onset of metamorphic climax (forelimb emergence) retained significantly less cadmium than animals exposed through larval stages. After exposure, cadmium partitioned predominantly in the skin, gills and remains of metamorphs, whereas larvae accumulated cadmium predominately through their gut. This shows a shift in the primary route of uptake at the onset of climax, which relates to the structural and functional changes of uptake sites through metamorphosis. During climax, some cadmium was redistributed in tissues developing de novo, such as the forelimbs, and concentrated in the regressing tail. Our findings highlight the need for stage-specific considerations in assessing exposure risks., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Chantal Lanctot reports equipment, supplies and travel were provided by Australian Nuclear Science and Technology Organisation. Chantal Lanctot reports financial support was provided by Australian Research Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

There is a growing need to understand the potential ecological impacts of contaminants in offshore oil and gas infrastructure, especially if that infrastructure is to be left in situ as a decommissioning option. Naturally occurring radioactive material (NORM) is one type of contaminant found in solid deposits on internal surfaces of infrastructure that poses potential ecological harm if released into the marine environment. Microbes are important components of marine sediment ecosystems because they provide ecosystem services, yet the impacts of NORM contamination to these communities are not well understood. The present study aimed to investigate the response of benthic microbial communities to NORM-contaminated scale, collected from an offshore oil and gas system, via controlled laboratory microcosm studies. Changes to microbial communities in natural sediment and sediments spiked with NORM at radium-226 activity concentrations ranging from 9.5 to 59.8 Bq/kg (in partial equilibria with progeny) over 7 and 28 days were investigated using high-throughput sequencing of environmental DNA extracted from experimental sediments. There were no significant differences in microbial community composition between control and scale-spiked sediments over 7 and 28 days. However, we observed a greater presence of Firmicutes in the scale-mixed treatment and Chloroflexi in the scale-surface treatments after 28 days. This could suggest selection for species with contaminant tolerance or potential resilience to radiation and metal toxicity. Further research is needed to explore microbial tolerance mechanisms and their potential as indicators of effects of radionuclide-contaminated sediments. The present study demonstrated that microcosm studies can provide valuable insights about the potential impacts of contamination from oil and gas infrastructure to sediment microbial communities. Environ Toxicol Chem 2024;43:1648-1661. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)

Contaminants, including naturally occurring radioactive material (NORM) of the 238-uranium and 232-thorium decay series, have been recognized as a global research priority to inform offshore petroleum infrastructure decommissioning decisions. This study aimed to characterize pipeline scale retrieved from a decommissioned subsea well tubular pipe through high-resolution elemental mapping and isotopic analysis. This was achieved by utilizing transmission electron microscopy, Synchrotron x-ray fluorescence, photostimulated luminescence autoradiography and Isotope Ratio Mass Spectrometry. The scale was identified as baryte (BaSO 4 ) forming a dense crystalline matrix, with heterogenous texture and elongated crystals. The changing chemical and physical microenvironment within the pipe influenced the gradual growth rate of baryte over the production life of this infrastructure. A distinct compositional banding of baryte and celestine (SrSO 4 ) bands was observed. Radioactivity attributed by the presence of radionuclides ( 226 Ra, 228 Ra) throughout the scale was strongly correlated with baryte. From the detailed scale characterization, we can infer the baryte scale gradually formed within the internals of the tubular well pipe along the duration of production (i.e., 17 years). This new knowledge and insight into the characteristics and formation of petroleum waste products will assist with decommissioning planning to mitigate potential radiological risks to marine ecosystems., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tom Cresswell reports financial support was provided by Undisclosed oil and gas industry partner. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: The Discovery Elbow System (DES) utilizes a polyethylene bearing within the ulnar component. An exchange bearing requires preoperative freezing and implantation within 2 minutes of freezer removal to allow insertion. We report our outcomes and experience using this technique., Methods: This was an analysis of a two-surgeon consecutive series of DES bearing exchange. Inclusion criteria included patients in which exchange was attempted with a minimum 1-year follow-up. Clinical and radiographic review was performed 1, 2, 3, 5, 8 and 10 years postoperative. Outcome measures included range of movement, Oxford Elbow Score (OES), Mayo Elbow Performance Score (MEPS), complications and requirement for revision surgery., Results: Eleven DESs in 10 patients were included. Indications were bearing wear encountered during humeral component revision (n=5); bearing failure (n=4); and infection treated with debridement, antibiotics and implant retention (DAIR; n=2). Bearing exchange was conducted on the first attempt in 10 cases. One case required a second attempt. One patient developed infection postoperatively managed with two-stage revision. Mean follow-up of the bearing exchange DES was 3 years. No further surgery was required, with no infection recurrence in DAIR cases. Mean elbow flexion-extension and pronosupination arcs were 107° (±22°) and 140° (±26°). Mean OES was 36/48 (±12) and MEPS was 83/100 (±19)., Conclusions: Our results support the use of DES bearing exchange in cases of bearing wear with well-fixed stems or acute infection. This series provides surgeons managing DES arthroplasty with management principles, successful and reproducible surgical techniques and expected clinical outcomes in performing DES polyethylene bearing exchange. Level of evidence: IV.

Naturally occurring radioactive materials (NORMs) can be found in decommissioned oil and gas infrastructure (e.g. pipelines), including scales. The effects of NORM contaminants from offshore infrastructure on benthic macroorganisms remain poorly understood. To test the potential ecological effects of NORM-contaminated scale, we exposed a marine amphipod, a clam and a polychaete to marine sediments spiked with low level concentrations of barium sulfate scale retrieved from a decommissioned subsea pipe. Only amphipods were included in further analysis due to treatment mortalities of the clam and polychaete. Barium (Ba) and copper (Cu) were elevated in the seawater overlying the spiked sediments, although no sediment metals exceeded guidelines. 210 Po was the only NORM detected in the overlying waters while both 210 Po and 226 Ra were significantly elevated in the scale-contaminated sediments when compared with the control sediments. The whole-body burden of Ba and 226 Ra were significantly higher in the scale-exposed amphipods. Using experiment- and scale-specific parameters in biota dose assessments suggested potential dose rates may elicit individual and population level effects. Future work is needed to assess the biological impacts and effects of NORM scale at elevated levels above background concentrations and the accumulation of NORM-associated contaminants by marine organisms., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Tom Cresswell reports financial support was provided by Undisclosed industry partner., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Agronomic biofortification of crops is a promising approach that can improve the nutritional value of staple foods by alleviating dietary micronutrient deficiencies. Iodine deficiency is prevalent in many countries, including Australia, but it is not clear what foliar application strategies will be effective for iodine fortification of grain. This study hypothesised that combining adjuvants with iodine in foliar sprays would improve iodine penetration in wheat, leading to more efficient biofortification of grains. The glasshouse experiment included a total of nine treatments, including three reference controls: 1) Water; 2) potassium iodate (KIO 3 ) and 3) potassium chloride (KCl); and a series of six different non-ionic surfactant or oil-based adjuvants: 4) KIO 3 + BS1000; 5) KIO 3 + Pulse ® Penetrant; 6) KIO 3 + Uptake ® ; 7) KIO 3 + Hot-Up ® ; 8) KIO 3 + Hasten ® and 9) KIO 3 + Synerterol ® Horti Oil. Wheat was treated at heading, and again during the early milk growth stage. Adding the organosilicon-based adjuvant (Pulse ® ) to the spray formulation resulted in a significant increase in grain loading of iodine to 1269 µg/kg compared to the non-adjuvant KIO 3 control at 231µg/kg, and the water and KCl controls (both 51µg/kg). The second most effective adjuvant was Synerterol ® Horti Oil, which increased grain iodine significantly to 450µg/kg. The Uptake ® , BS1000, Hasten ® , and Hot-Up ® adjuvants did not affect grain iodine concentrations relative to the KIO 3 control. Importantly, iodine application and the subsequent increase in grain iodine had no significant effects on biomass production and grain yield relative to the controls. These results indicate that adjuvants can play an important role in agronomic biofortification practices, and organosilicon-based products have a great potential to enhance foliar penetration resulting in a higher translocation rate of foliar-applied iodine to grains, which is required to increase the iodine density of staple grains effectively., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Magor, Wilson, Wong, Cresswell, Sánchez-Palacios, Bell and Penrose.)

As oil and gas infrastructure comes to the end of its working life, a decommissioning decision must be made: should the infrastructure be abandoned in situ, repurposed, partially removed, or fully removed? Environmental contaminants around oil and gas infrastructure could influence these decisions because contaminants in sediments could degrade the value of the infrastructure as habitat, enter the seafood supply if the area is re-opened for commercial and/or recreational fishing, or be made biologically available as sediment is resuspended when the structures are moved. An initial risk hypothesis, however, may postulate that these concerns are only relevant if contaminant concentrations are above screening values that predict the possibility of environmental harm or contaminant bioaccumulation. To determine whether a substantive contaminants-based risk assessment is needed for infrastructure in the Gippsland Basin (South-eastern Australia), we measured the concentration of metals and polycyclic aromatic hydrocarbons (PAHs) in benthic sediments collected around eight platforms earmarked for decommissioning. The measurements were compared to preset screening values and to background contaminant concentrations in reference sites. Lead (Pb), zinc (Zn), PAHs and other contaminants were occasionally measured at concentrations that exceeded reference values, most often within 150 m of the platforms. The exceedance of a few screening values by contaminants at some platforms indicates that these platforms require further analysis to determine the contaminant risks associated with any decommissioning option., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Thousands of oil and gas structures have been installed in the world's oceans over the past 70 years to meet the population's reliance on hydrocarbons. Over the last decade, there has been increased concern over how to handle decommissioning of this infrastructure when it reaches the end of its operational life. Complete or partial removal may or may not present the best option when considering potential impacts on the environment, society, technical feasibility, economy, and future asset liability. Re-purposing of offshore structures may also be a valid legal option under international maritime law where robust evidence exists to support this option. Given the complex nature of decommissioning offshore infrastructure, a global horizon scan was undertaken, eliciting input from an interdisciplinary cohort of 35 global experts to develop the top ten priority research needs to further inform decommissioning decisions and advance our understanding of their potential impacts. The highest research priorities included: (1) an assessment of impacts of contaminants and their acceptable environmental limits to reduce potential for ecological harm; (2) defining risk and acceptability thresholds in policy/governance; (3) characterising liability issues of ongoing costs and responsibility; and (4) quantification of impacts to ecosystem services. The remaining top ten priorities included: (5) quantifying ecological connectivity; (6) assessing marine life productivity; (7) determining feasibility of infrastructure re-use; (8) identification of stakeholder views and values; (9) quantification of greenhouse gas emissions; and (10) developing a transdisciplinary decommissioning decision-making process. Addressing these priorities will help inform policy development and governance frameworks to provide industry and stakeholders with a clearer path forward for offshore decommissioning. The principles and framework developed in this paper are equally applicable for informing responsible decommissioning of offshore renewable energy infrastructure, in particular wind turbines, a field that is accelerating rapidly., Competing Interests: Declaration of competing interest Watson (first author) – received funding from the National Environmental Science Program (NESP) Marnane (co-author) – is an employee of Chevron Technology Energy Fokkema (co-author) – is an employee of Shell Global Solutions International, (Crown Copyright © 2023. Published by Elsevier B.V. All rights reserved.)

This modelling study uses the ERICA Tool and Bateman's equation to derive sediment threshold values for radiation protection of the marine environment relevant to NORM-contaminated products (radium-contaminated scales, 210 Pb films and 210 Po films) found in subsea oil and gas infrastructure. Threshold values are calculated as the activity concentration of the NORM-contaminated products' head of chain radionuclide (i.e., 226 Ra + 228 Ra, 210 Pb, or 210 Po) that will increase radiation dose rates in sediments by 10 μGy/h to the most exposed organism at a given release time. The minimum threshold value (corresponding to peak radiation dose rates from the ingrowth of progeny) were for radium-contaminated scales, 0.009 Bq/g of 226 Ra, 0.029 Bq/g of 228 Ra (in the absence of 226 Ra) or 0.14 Bq/g of 228 Ra (in the presence of 226 Ra), followed by 0.015 Bq/g for 210 Pb films, and 1.6 Bq/g for 210 Po films. These may be used as default threshold values. Added activity concentrations of the NORM-contaminated products to marine sediments below these threshold values implies a low radiological risk to organisms while exceedances imply that further investigation is necessary. Using contaminated product specific parameterisations, such as K d values derived for Ra from a BaSO 4 matrix in seawater, could greatly affect threshold values. Strong consideration should be given to deriving such data as part of specific radiological risk assessments for these products., Competing Interests: Declaration of competing interest NERA, an independent scientific advisory board, and industry partners provided insights to the authors from their respective experience and provided comments to a report from which this manuscript was drafted. The NDRI project was funded by eight industry partners including Shell Australia, Esso Australia, Chevron Australia, BHP Petroleum, Woodside Energy, Santos Limited, ConocoPhillips Pipeline Australia, and Vermilion Oil and Gas Australia. This funding source has not influenced any of the authors objectivity. All views expressed within the paper are those of the authors., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aims: Multiple studies have shown excellent clinical results in primary rotator cuff repairs; however, not much evidence is available in the literature on the outcomes of arthroscopic revision rotator cuff repairs. The purpose of this study was to report a cohort of patients who underwent revision arthroscopic rotator cuff repair and identify factors that may influence its outcomes., Methods: We examined a cohort of 62 patients which underwent revision arthroscopic rotator cuff repair in a single UK institution with a minimum of 24 months follow-up. Active shoulder movements including forward flexion, abduction and external rotation were evaluated, as well as Oxford Shoulder Score (OSS). Further subgroup analysis was performed looking of the effects of age, size of tear, obesity and diabetes mellitus had on clinical outcomes., Results: 59 patients were available for final review. 39 male and 23 were female. The mean age was 64 years. Overall, significant improvements were seen in terms of OSS ( p  < 0.05), active forward flexion ( p  < 0.05), active abduction ( p  < 0.05) and active external rotation ( p  < 0.05). Our study showed that a significant proportion of patients undergoing arthroscopic revision rotator cuff repair achieve good outcomes. Repairing small- and medium-size tears was successful, diabetics had no post-operative improvements, obese patients achieved significant improvement in range of movement and age was not a predictor of surgical success., Conclusion: Overall, arthroscopic revision surgery is a successful option; however, appropriate patient selection and counselling is paramount., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Indian Orthopaedics Association 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Scale residues can accumulate on the interior surfaces of subsea petroleum pipes and may incorporate naturally occurring radioactive materials (NORM). The persistent nature of 'NORM scale' may result in a radiological dose to the organisms living on or near intact pipelines. Following a scenario of in-situ decommissioning of a subsea pipeline, marine organisms occupying the exteriors or interiors of petroleum structures may have close contact with the scale or other NORM-associated contaminated substances and suffer subsequent radiological effects. This case study used radiological dose modelling software, including the ERICA Tool (v2.0), MicroShield® Pro and mathematical equations, to estimate the likely radiological doses and risks of effects from NORM-contaminated scale to marine biota from a decommissioned offshore oil and gas pipeline. Using activity concentrations of NORM ( 226 Ra, 210 Po, 210 Pb, 228 Ra, 228 Th) from a subsea pipeline from Australia, environmental realistic exposure scenarios including radiological exposures from both an intact pipe (external only; accounting for radiation shielding by a cylindrical carbon steel pipe) and a decommissioned pipeline with corrosive breakthrough (resulting in both internal and external radiological exposure) were simulated to estimate doses to model marine organisms. Predicted dose rates for both the external only exposure (ranging from 26 μGy/h to 33 μGy/h) and a corroded pipeline (ranging from 300 μGy/h to 16,000 μGy/h) exceeded screening levels for radiological doses to environmental receptors. The study highlighted the importance of using scale-specific solubility data (i.e., K d ) values for individual NORM radionuclides for ERICA assessments. This study provides an approach for conducting marine organism dose assessments for NORM-contaminated subsea pipelines and highlights scientific gaps required to undertake risk assessments necessary to inform infrastructure decommissioning planning., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Many oil and gas fields are nearing production cessation and will require decommissioning, with the preferred method being complete infrastructure removal in most jurisdictions. However, decommissioning in situ, leaving some disused components in place, is an option that may be agreed to by the regulators and reservoir titleholders in some circumstances. To understand this option's viability, the environmental impacts and risks of any residual contaminants assessed. Mercury, a contaminant of concern, is naturally present in hydrocarbon reservoirs, may contaminate offshore processing and transmission infrastructure, and can biomagnify in marine ecosystems. Mercury's impact is dependent on its speciation, concentration, and the exposure duration. However, research characterising and quantifying the amount of mercury in offshore infrastructure and the efficacy of decontamination is limited. This review describes the formation of mercury-contaminated products within oil and gas infrastructure, expected exposure pathways after environmental release, possible impacts, and key research gaps regarding the ecological risk of in situ decommissioned contaminated infrastructure. Suggestions are made to overcome these gaps, improving the in situ mercury quantification in infrastructure, understanding environmental controls on, and forecasting of, mercury methylation and bioaccumulation, and the cumulative impacts of multiple stressors within decommissioned infrastructures., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Per- and polyfluoroalkyl substances (PFAS) are a challenging class of environmental pollutants due to a lack of available destructive remediation technologies. Understanding the fundamental mechanisms for degradation of PFAS is key for the development of field scalable and in-situ destructive based remediation technologies. This study aimed to elucidate and refine the current understanding of PFAS degradation mechanisms in water through a series of controlled gamma irradiation studies. Gamma irradiation of PFAS was performed using a cobalt-60 source in a batch irradiation up to 80 kGy at the Australian Nuclear Science and Technology Organisation. Perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), 6:2 fluorotelomer sulfonate (6:2 FTS), and a suite of thirteen different PFAS (including C4-C12 PFCAs, C4, C6, C8 PFSAs, and FOSA) were irradiated to investigate degradation, influence of pH, chain length, and transformation. High resolution mass spectrometry was used to identify more than 80 fluorinated transformation products throughout the degradation experiments. These included the -F/+H, -F/+OH, -F/CH 2 OH exchanged PFAS and n - 1 PFCA, amongst others. Given the reactive species present (hydroxyl radicals (·OH), hydrogen radicals (·H) and aqueous electrons (e - aq )), and the degradation products formed it was shown that aqueous electrons were the key reactive species responsible for initial PFAS degradation. Most importantly, based on degradation product formation, we found that the initial -F/+H does not have to occur at the α-fluoride (nearest the functional head group), rather occurring throughout the chain length leading to more complex degradation pathways than previously postulated. While our results support some of the reaction steps postulated in the literature, we have developed a unified 16 step and 3 pathway schematic of degradation supported by experimental observations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)