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Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL⁻¹) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL⁻¹ (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot.

Sustainable remediation is a new way of thinking and acting in the management of contaminated sites. This research aims to identify and structure the state-of-the-art of sustainable remediation from the risk management and stakeholder involvement perspective. A systematic and bibliometric study of scientific production was performed on scientific papers indexed in the Scopus and Web of Science databases with the objectives: 1) to select a bibliographic portfolio that is aligned with the perception of the researchers in regard to theme, 2) to perform a bibliometric analysis of the selected bibliographic portfolio, and 3) to conduct a thematic synthesis and identify the integration of sustainable remediation from the risk management and stakeholder involvement perspective. The results indicated that although sustainable remediation is a recent theme it presents a promising field for development worldwide, verified by the growing number of publications in recent years. A change is observed in the way risk management is considered with the rise of sustainable remediation, demonstrated by different approaches in publications. Likewise, the involvement of stakeholders is widely discussed, and the importance of their participation in decision-making processes in the field of sustainable remediation is identified. This research brings several and new contributions as it provides with a detailed overview and guidance about the main characteristics and peculiarities as well as what already exists, the form to approach, the advances and what still needs to be improved so that the perception of stakeholders and risk management are better understood within the context of sustainable remediation.

The impacts of iron oxide nanoparticles (γ-Fe2O3 NPs) and ferric ions (Fe³⁺) on plant growth and molecular responses associated with the transformation and transport of Fe²⁺ were poorly understood. This study comprehensively compared and evaluated the physiological and molecular changes of Citrus maxima plants as affected by different levels of γ-Fe2O3 NPs and Fe³⁺. We found that γ-Fe2O3 NPs could enter plant roots but no translocation from roots to shoots was observed. 20 mg/L γ-Fe2O3 NPs had no impact on plant growth. 50 mg/L γ-Fe2O3 NPs significantly enhanced chlorophyll content by 23.2% and root activity by 23.8% as compared with control. However, 100 mg/L γ-Fe2O3 NPs notably increased MDA formation, decreased chlorophyll content and root activity. Although Fe³⁺ ions could be used by plants and promoted the synthesis of chlorophyll, they appeared to be more toxic than γ-Fe2O3 NPs, especially for 100 mg/L Fe³⁺. The impacts caused by γ-Fe2O3 NPs and Fe³⁺ were concentration-dependent. Physiological results showed that γ-Fe2O3 NPs at proper concentrations had the potential to be an effective iron nanofertilizer for plant growth. RT-PCR analysis showed that γ-Fe2O3 NPs had no impact on AHA gene expression. 50 mg/L γ-Fe2O3 NPs and Fe³⁺ significantly increased expression levels of FRO2 gene and correspondingly had a higher ferric reductase activity compared to both control and Fe(II)-EDTA exposure, thus promoting the iron transformation and enhancing the tolerance of plants to iron deficiency. Relative levels of Nramp3 gene expression exposed to γ-Fe2O3 NPs and Fe³⁺ were significantly lower than control, indicating that all γ-Fe2O3 NPs and Fe³⁺ treatments could supply iron to C. maxima seedlings. Overall, plants can modify the speciation and transport of γ-Fe2O3 NPs or Fe³⁺ for self-protection and development by activating many physiological and molecular processes.

Coastal environments, essential for about half of the world's population living near coastlines, face severe threats from human-induced activities such as intensified urbanization, aggressive development, and particularly, coastal sewage pollution. This type of pollution, comprising untreated sewage discharging nutrients, pathogens, heavy metals, microplastics, and organic compounds, significantly endangers these ecosystems. The issue of sewage in coastal areas is complex, influenced by factors like inadequate sewage systems, septic tanks, industrial and agricultural runoff, and natural processes like coastal erosion, further complicated by oceanic dynamics like tides and currents. A global statistic reveals that over 80 % of sewage enters the environment without treatment, contributing significantly to nitrogen pollution in coastal ecosystems. This pollution not only harms marine life and ecosystems through chemical contaminants and eutrophication, leading to hypoxic zones and biodiversity loss, but also affects human health through waterborne diseases and seafood contamination. Additionally, it has substantial economic repercussions, impacting tourism, recreation, and fisheries, and causing revenue and employment losses. Addressing this issue globally involves international agreements and national legislations, but their effectiveness is hindered by infrastructural disparities, particularly in developing countries. Thus, effective management requires a comprehensive approach including advanced treatment technologies, stringent regulations, regular monitoring, and international cooperation. The international scientific community plays a crucial role in fostering a collaborative and equitable response to this pressing environmental challenge.

Marine debris is a global issue with adverse impacts on marine organisms, ecological processes, aesthetics, and economies of nations. Several studies have been conducted to quantify the plastic debris along Indian beaches. This baseline study describes the results of a survey conducted on the types of plastic litters and their quantification during January to March 2020 along Mandvi beach in Gujarat. A quadrate having 10 × 10 m size was used for sampling the plastic litter on the shoreline. A total of 10 quadrates along the shore was considered for quantification of the plastic materials based on their density, color, and weight. The plastic material observed includes gutkha pouches, food wrappers, and fragments, along with plastic straws, cutleries, and fragments of various dimensions and thickness. The major contributing factors for the debris abundance in Mandvi beach are land-based sources and recreational activities. The results suggest that similar long-term projects covering extensive areas should be undertaken for accurate quantification of available debris and their impacts on coastal habitats of Gujarat.

Mangrove tidal wetland habitats are recognised as highly vulnerable to large and chronic oil spills. This review of current literature and public databases covers the last 6 decades, summarising global data on oil spill incidents affecting, or likely to have affected, mangrove habitat. Over this period, there have been at least 238 notable oil spills along mangrove shorelines worldwide. In total, at least 5.5milliontonnes of oil has been released into mangrove-lined, coastal waters, oiling possibly up to around 1.94millionha of mangrove habitat, and killing at least 126,000ha of mangrove vegetation since 1958. However, there were assessment limitations with incomplete and unavailable data, as well as unequal coverage across world regions. To redress the gaps described here in reporting on oil spill impacts on mangroves and their recovery worldwide, a number of recommendations and suggestions are made for refreshing and updating standard operational procedures for responders, managers and researchers alike.

Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712±780gDWm−2 and 1511±555gDWm−2, respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31±4.45, 402.82±130.25, and 28.12±2.08, respectively. The δ15N values (11.09±0.91‰ for C. linum; 9.27±2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms.

Benthic octopuses have been widely documented in artificial shelters for decades, and this use is apparently increasing. Despite any possible positive effects, the use of litter as shelter could have negative implications. In this work, we aimed to elucidate the interactions of octopuses with marine litter, identifying types of interactions and affected species and regions. To achieve this, we obtained 261 underwater images from ‘citizen science’ records, and identified 8 genera and 24 species of benthic octopuses interacting with litter. Glass objects were present in 41.6% of interactions, and plastic in 24.7%. Asia presented the highest number of images, and most records were from 2018 to 2021. Citizen science provided important evidence on octopus/marine litter interactions, highlighting its value and the need for more investigations on the subject. This information is fundamental to help prevent and mitigate the impacts of litter on octopuses, and identify knowledge gaps that require attention.