Coastal zones, which are strategic points of considerable importance to the tourism industry, are among the environments most affected by anthropogenic debris. Thus, it is crucial to monitor and implement management programs to provide immediate solutions. Here, we aimed to evaluate anthropogenic litter along 21 macrotidal sandy beaches in the Amazon region. Indices and multivariate statistical analyses were used to identify spatial patterns of pollution, as well as sources and lifetime of the items. A total of 20,286 items were collected, with an average density of 0.19 items/m² and a predominance of plastics. Litter was associated with tourist and recreational activities. The lifetime of most items was <1 year. All beaches had intermediate levels of pollution. The analyses identified varying patterns of anthropogenic litter related to the cleaning frequency and waste item typologies. In conclusion, pollution of macrotidal beaches in the Amazon region is an emerging problem that requires measures to prevent and mitigate the impacts on this ecosystem and to reconsider the form of production and consumption of plastic waste.

Diverse litter studies on Colombia's Central Caribbean Coast have presented the Microplastic issues regarding typology, magnitudes, and distribution. No studies have examined MPs' presence and abundances in relation to sediment grain size and the sediments statistical parameters (mean, median, sorting, skewness, kurtosis). This work attempts to fill this information gap in a study of 15 sampling sites along Colombia's Central Caribbean Coast. Sediment samples were collected and analysed to determine sediment granulometric properties, in association with the presence, magnitudes, shapes, and impact of MPs, and their possible relationships. Within the study area, grain size distribution was similar between surveyed sites, with a dominance of three textural groups: sands, slightly gravelly sands, and slightly gravelly muddy sands. In terms of size-sorting categories, the percentages were moderately well sorted (60 %), moderately sorted (20 %), well sorted (13 %), and very well sorted (7 %). Microplastic abundances (densities) ranged from 160 to 1120 MPs/kg, similar to other global beaches. Microplastic fibers were the dominant typology at 86.8 % of the combined beaches total. Multiple linear regression analysis suggested that approximately 30 % of the MPs' presence could be related to changes in the five sediment statistics used in this work, being the most important statistical parameter sorting with 11 % (r² = 0.27 - F-Statistic = 0.67). To manage the MP issue, reducing the current elevated plastic inputs into the environment is necessary/mandatory. Approaches to reach this goal must be focused on the entire plastic life cycle (extraction, design, production, use, disposal, recovery, recycling).

Understanding the accumulation mechanism for beached plastics is important for marine debris research. Similar to the global accumulation pattern for beached plastics, we find that along the remote south coast of Western Australia (SCWA) white, hard, microplastics dominate the microplastic pollution accumulating on beaches. We estimate that along the SCWA, plastics are present at a density of 2.01 items·m⁻², but also find that the density of plastic pollution is higher at the eastern end of bays. Significantly fewer plastics were found after easterly winds (austral summer-prevailing winds), and regional physical ocean process, including the Leeuwin Current, and the Ekman transport effect may be relevant to the rate of plastic accumulation on SCWA beaches.

Deposition of tar balls on the Qinhuangdao beaches along the coasts of the Bohai Sea (China) could affect people's leisure activities and tourism, and even affect the marine ecosystem. In 2020, representative tar balls collected from Qinhuangdao beaches, fingerprint analysis based on diagnostic ratios suggested that these tar balls were all very similar and may belong to the same source. Source identification by cross plot and principal component analysis (PCA), showed that the tar balls were likely from Penglai 19–3 crude oil. The weathering characterizations based on polycyclic aromatic hydrocarbons (PAHs), alkanes parameters and unresolved complex mixture (UCM), indicated that the tar balls had been significantly influenced by natural weathering processes such as evaporation, biodegradation and photooxidation. The study of this leakage provides a powerful support for determining the leakage source, evaluating the potential weathering mechanism and determining the accident liability. This is the first time to use fingerprint technology to identify the source of tar balls in Qinhuangdao coastal zone in the Bohai Sea.

Establishing geochemical baselines and assessment of heavy metal pollution in lagoon sediments are critical for providing guidance to coastal zone environmental management. We analyzed heavy metals in high-resolution sediment cores from Pinqing Lagoon in South China, and defined the baselines of common pollution elements with a significant anthropogenic contribution. With these baselines, a spatiotemporal pollution assessment revealed Cu and Cd as the predominant pollution metals in both core and surface sediments, although the ecological risk level in the interior lagoon remained low during the past ~170 years. Surface sediment pollution status indicate a significant spatial difference. The findings from this typical coastal lagoon evidence a strong self-clean capacity attributable to the frequent water-mass-energy exchange between the lagoon and the sea. Furthermore, despite the significant impact by the sea, the geochemical baselines are close to the catchment soil backgrounds that can be defined using a paleolimnological approach.

The distribution characteristics of lipophilic marine biotoxins (LMTs), such as yessotoxins (YTXs) and pectenotoxins (PTXs) in phytoplankton, mussels, and commercial seafood were determined for the southern coast of South Korea. Gonyaulax spinifera and Dinophysis acuminata, which are the causative microalgae of YTXs and PTXs, were recorded during summer. Homo-YTX and PTX-2 were predominantly detected in phytoplankton (max: 5.7 μg g⁻¹ ww), whereas only YTXs were detected in mussels (max: 1.1 μg g⁻¹ ww). LMT concentrations in mussels were positively correlated with those in phytoplankton. However, there was a 1-month time gap in maximum LMT concentrations between mussels and phytoplankton. Homo-YTX was detected in commercial seafood, including red scallop and comb pen shell. However, homo-YTX concentrations in shellfish were below the recommended value of the European Food Safety Authority (3.75 mg YTX equivalents kg⁻¹); thus, the consumption of this seafood was not considered to be a significant risk for human health.

With several observable responses and sensitivity of protozoans to nitrofurazone (NFZ), the toxic effects of NFZ on protozoans can be an early warning signal of NFZ contamination in the aquatic environment. To evaluate the toxic dynamics induced by NFZ, protozoan samples were collected using microscopy glass slides and exposed to the five concentrations of NFZ: 0, 1, 2, 4, and 8 mg ml⁻¹. Substantial differences in the species composition and toxic-dynamics patterns were observed among all concentrations. Briefly, periphytic euplotids and pleurostomatids were the most prevalent at each concentration level, while dysteriids were less dominant among all treatments. Multivariate analysis revealed significant (P < 0.05) differences in the taxonomic patterns of the test organisms among the five treatments. Furthermore, significant deviation of protozoan communities from the expected taxonomic breadth was observed to occur in a dose-dependent manner. Based on these findings, it is suggested that protozoan periphytons could be used as bioindicators to assess the ecotoxicity of NFZ in the marine environment.

Studies integrating trophic ecology, physiological condition and accumulation of heavy metals in top predators, such as swordfish, are needed to better understand the links between them and the risk to humans associated with consumption of these fish. This research focuses on the swordfish of the Catalan Sea and follows a multi method approach that considers their diet, their liver lipid content, and mercury accumulation in their bodies as well as in their prey. The aim is to highlight the links between trophic ecology, physiology (fish condition), and eco-toxicology. Results indicate that poor condition of swordfish based on size and the levels of lipid in the liver, and the high Hg levels accumulated to the trophic web (particularly from cephalopods) may indicate potential unfavourable feeding and reproduction conditions for swordfish in the NW Mediterranean and this warrants further investigation.

The last decades have shown that human activities damaged environmental quality and biodiversity. As accepted the need of sustainable development, there should be balance between economic, social and environmental issues in the long term. Ecological footprint is an important indicator that shows how human activities reduce environmental quality among a specific region or country. In addition, human capital is mostly used indicator to estimate economic and environmental development level. In this study, it is aimed to explore the effect of human capital on fishing footprint for 10 Mediterranean Countries during the period 1995–2018. According to empirical evidences, it is concluded that for relatively low human capital level, human capital has negative effect on sustainability and in the relatively high level, it has positive effect on sustainability.

Rare earth elements (REEs) are increasingly used in various industries worldwide, resulting in their release into aquatic ecosystems. We evaluated the distribution and bioaccumulation of 14 REEs in marine sediments and biotas along the Chinese coasts. The total concentration of REEs (ΣREEs) in sediments was 41.65–170.94 mg/kg. The concentrations of ΣREEs were 1.97–4.77 and 0.62–4.96 mg/kg dry mass (DM) for oysters and mussels. The concentration of total light REEs (ΣLREEs) was higher than the concentration of total heavy REEs (ΣHREEs) at all samples. The bioaccumulation factor (BAF) of ΣLREEs was higher than ΣHREEs and BAF of ΣREE was 0.34–1.49 and 0.25–1.10 for oysters and mussels. The positive correlation between sediments and biotas was higher in mussels than oysters, showing a good potential for being environmental indicators for REEs. The risk of REEs to humans via oysters and mussels consumption could be negligible based on the estimated daily intake.