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The metal Gadolinium (Gd) is a member of the lanthanide (Ln) group and is recognized as an emerging pollutant due to its widespread application in modern technology. Its acute toxicity depends on its free ion concentrations (Gd3 +), which is directly related to chemical speciation. The Biotic Ligand Model (BLM) is a valuable tool for risk assessment which predicts the metal bioavailability and toxicity to specific organisms. However, studies developing BLM for any Ln species are rare. Consequently, this study aimed to develop a kinetic BLM to predict the acute toxicity of Gd to the freshwater crustacean Daphnia magna. A series of 48-hour toxicity tests were conducted using different major cation concentrations, in order to estimate their affinity constants for the biotic ligand (BL). The model was then validated, first in the presence of dissolved organic matter (DOM), and then with water samples collected from lakes, rivers, and estuaries in France and Germany. The outcome revealed that three major cations (potassium, magnesium, and calcium) act as strong competitors. The model was successfully validated in the presence of organic matter and in the majority of surface freshwater samples (9 out of 13 samples). In this case, the predicted survival had a strong fit with the observed data. However, this was reduced when applying the model to samples of elevated electroconductivity and a pH below 6.8, when survival was consistently overestimated, potentially a multistressor effect. The kinetic BLM predicted 48 h measured EC50 ranging from 4 to 30 mg L−1 which agreed with the data from the literature. The model could also predict chronic effect of Gd by estimating the no-effect concentration (NEC) under prolonged exposure time ranging from 0.1 to 1 mg L−1.

Background This paper examines the suitability of extant governance frameworks at an international level for addressing antimicrobial resistance (AMR), which is a creeping crisis for global health security. Methods Our study begins by evaluating the place of antimicrobial resistance (AMR) within United Nations (UN) Sustainable Development Goals (SDG) targets and indicators. This is followed by a discussion of the global health security agenda (GHSA). We examine how AMR needs to be taken more seriously within global policy frameworks based on adopting a One Health approach. The research is supported by a systematic analysis of the national action plans for addressing AMR published by the World Health Organisation (WHO). Results We determine that political leaders need to do more to promote the problem of AMR and that global health institutions need to invest more energy in thinking about how AMR is governed as part of an already busy global health security agenda. This includes building capacities within health systems, embedding evaluation processes, and enhancing public service leadership within this area. Conclusions Our review of global policy frameworks and the national plans for AMR highlight the patchy coverage of AMR strategies globally and nationally. This article represents a springboard for future research including whether and to what extent a One Health approach to AMR in the environment has been implemented in practice within national health and environmental systems.

Waste electrical and electronic equipment (WEEE) are a source of both hazardous and valuable materials that must be segregated for treatment. Previous studies addressing the use of handheld X-Ray fluorescence (h-XRF) as a sorting tool for WEEE plastics through the identification of hazardous components include plastics from mixed WEEE streams, processed material (shredded or treated plastics) and low number of samples not allowing to consider their findings for application on an industrial scale. Thus, further research is needed to establish scalable robust methods for sorting this material. We describe a study carried out on whole flat panel display equipment (FPD) plastic casings using h-XRF for the detection of total bromine (Br) and antimony (Sb) as tracers for Brominated Flame Retardants (BFRs) and Sb2O3 additives. The aim being to characterize the targeted material and to define the optimal analysis conditions to meet large scale throughputs. A ring trial exercise comprising 100 samples was conducted to evaluate the validity of the measurements. Results indicate that: 1) the use of h-XRF under the conditions determined in this study offers a valid technique to screen total Br and Sb in whole FPD casings at industrial scale with low uncertainty, 2) Br and Sb are found to be homogeneously distributed within the casing, 3) an optimal h-XRF analysis time of 10 seconds is suitable from both accuracy and practical implementation for LOD

The Miocene Zhujiang Formation is the key horizon for oil and gas exploration in the Pearl River Mouth basin of northern South China Sea. With the help of core observation, seismic attributes and various analytical data, the sedimentary facies marks, distribution of sedimentary facies and depositional model of forced regression in the Miocene Zhujiang Formation of the Pearl River Mouth basin, northern South China Sea, have been studied. Forced regressive deposits were formed during the period when relative sea level ranged from highstand to lowstand and the sediments were forced to undergo progradation so that five sets of foreset delta deposits are developed in turn. In the early stage of forced regression, the normal delta where the delta plain, delta front and prodelta are not absent mainly developed. In the later stage of forced regression, the shelf edge delta with only the delta front and the prodelta, the longshore bar along the shelf break and the turbidite fan in the deep water of the slope area were developed. The favorable reservoir of forced regressive deposits are located near the upper boundary of the falling stage systems tract and the basal surface of forced regression, and they are the sand bodies of shelf edge delta, longshore bar and turbidite fan. The research results may provide guidance for reservoir prediction.