Metal concentrations were concurrently quantified in seawater, phytoplankton, and zooplankton from a heavily impacted coast of southern Taiwan. Combined size and density fractionation were used to accurately quantify metal concentrations in phytoplankton. Cr, Co, Ni, Cu, As, and Pb were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS). As expected, metals significantly increased with an order of seawater < phytoplankton < zooplankton (p < 0.05); but did not differ between estuarine, nearshore, and offshore sites (p > 0.05). Metals were higher along Kaohsiung Harbor and marine outfall diffusion sites, highlighting their major impacts on plankton metal contamination. Notably, phytoplankton (Cr BCF > 100; half of the sites) significantly accumulated more metals contrary to zooplankton (BAF < 10). Metal concentrations and bioaccumulation factors between phytoplankton and zooplankton showed significant negative correlations. This demonstrates a non-proportional distribution and bioaccumulation of metals in phytoplankton and zooplankton—corroborating laboratory findings on zooplankton ability to control metals, irrespective of significantly high bioaccumulation in phytoplankton.

This paper aims to determine the worldwide research trends on searching queries of “oil spill* and risk assessment*” and “net environmental benefit analysis” and its most productive authors and journals. A bibliometric approach was performed to analyze publications including highly cited papers and only papers that were published in the Dimensions database from 2000 to 2022, April was selected. The necessary data were extracted from the Dimensions database and processed using visualization and mapping software such as VOSviewer 1.6.17 and Tableau Public 2021.1. The findings identified significant study fields, co-cited authors, country contributions, productive journals, as well as the most cited authors' articles. This study contributes significantly to the relevant studies as one of the few that utilizes bibliometric analysis as a network visualization and mapping technique for the analysis of one of the primary oil spill response decision-making tools and risk assessment sciences. The findings of this study can assist the researcher perform their research more effectively by providing insight into journal selection, contributing authors, research trends, countries, and keywords. Further research is recommended in light of longer period data contained in oil spill response strategies, oil spill modeling, or oil spill risk subjects.

This is the first report about the presence of pesticide residues in water and sediments from Chacahua-Pastoria Lagoon System in the Oaxaca Coast, Mexico. Organochlorine and organophosphate pesticides were analyzed in water and sediment samples collected during rainy and dry seasons in 2018. The pesticides extraction was carried out by 525.2 EPA and QuEChERS methods for water and sediments samples, respectively. The quantification was done by gas chromatography coupled to electron microcapture (μECD) and flame photometric (FPD) detectors. Univariate and multivariate analysis were carried out to evaluate the distribution patterns, comparing between lagoons, seasons and matrices. The spatial distribution of malathion and organochlorines in water showed the highest values near to adjacent land with some patterns differences. DDT was the most frequent in water and sediments samples, showed the highest concentrations in the Pastoria Lagoon. These results indicate the need to establish a permanent monitoring programs to implement mitigation measures.

The present study aims to assess the effects of contamination of the Agadir bay coasts using bivalves as a biomonitoring sentinel species. Seasonal variations of biochemical composition in terms of total protein content and oxidative stress biomarkers including glutathione-S-transferase, malondialdehyde, catalase and acetylcholinesterase were evaluated in the soft tissues of Scrobicularia plana and Donax trunculus specimens. The latter were collected from two sites in Agadir bay during two-year span (2018–2020). The Integrated Biomarker Response Index (IBR) was performed to classify the stress response in both species and to assess the level of exposure to xenobiotics. The data showed maximum annual values of acetylcholinesterase and malondialdehyde for Donax trunculus in Agadir beach (AG) with 6.25 nmol/mn/mg and 3 nmol/mg of protein, respectively. Those of catalase and glutathione-S-transferase for Scrobicularia plana in Oued Souss estuary (OS) were of 4.41 μmol/mn/mg and 14.43 nmol/mn/mg of protein, respectively. The studied species are considered good indicators in aquatic ecosystems.

We determined concentrations of Hg, Pb, Cd, Cr, As, Ni, Ag, Se, Cu, and Zn in muscle tissue of six commonly consumed Long Island fish species (black seabass, bluefish, striped bass, summer flounder, tautog, and weakfish, total sample size = 1211) caught off Long Island, New York in 2018 and 2019. Long-term consumption of these coastal fish could pose health risks largely due to Hg exposure; concentrations of the other trace elements were well below levels considered toxic for humans. By combining the measured Hg concentrations in the fish (means ranging from 0.11 to 0.27 mg/kg among the fish species), the average seafood consumption rate, and the current US EPA Hg reference dose (0.0001 mg/kg/d), it was concluded that seafood consumption should be limited to four fish meals per month for adults for some fish (bluefish, tautog) and half that for young children. Molar ratios of Hg:Se exceeded 1 for some black seabass, bluefish, tautog, and weakfish.

Marine debris is an environmental issue of increasing importance worldwide, with 80% of marine plastics estimated to originate from land-based sources. While much work has been conducted to quantify plastics in coastal environments, many of these approaches are site-specific and not amenable to rapid surveys. We surveyed beaches around Nova Scotia, Canada for plastic and other anthropogenic debris to: 1) quantify debris density on the high tide line; and 2) test a rapid survey technique using digital photos, with applications for community science and remote regions. Most (72%) beaches in Nova Scotia contained debris, but plastic densities along the daily high tide line were relatively low (mean 0.2 debris/m²) with little interannual variation. Despite small differences in plastic densities between observers, this rapid assessment technique appears viable for relative quantification and monitoring of plastic debris on beaches across large geographic scales to assess trends and sources.

Motorized vessels are a major source of anthropogenic noise and can have adverse effects on species relying on sound for communication and feeding. Monitoring noise levels received by endangered southern resident killer whales (SRKWs) requires knowing the number, distance, and speed of surrounding vessels, including small boats that do not have Automatic Identification Systems (AIS). A method for estimating their speed is required to predict received noise levels and compliance with vessel regulations. We compared theodolite and photogrammetry methods to estimate the number, distance, and speed of vessels in SRKW Salish Sea summertime critical habitat. By treating AIS as “truth”, we found photogrammetry-derived ranges and speeds were more variable than theodolite estimates. Error in photogrammetry-derived speeds increased with range. Overall, we found time saved in the field using photogrammetry was more than offset by long analysis time. Theodolite data were relatively easy to collect, and produced accurate and precise results.

Off-flavours in fish products generated from recirculating aquaculture systems (RAS) are a major problem in the fish farming industry affecting the market demand and prices. A particular concern is the muddy or musty odour and taste in fish due to the presence of secondary metabolites geosmin and 2-methylisoborneol (2-MIB), produced by actinobacteria (mainly Streptomyces), myxobacteria and cyanobacteria. Off-flavours have deteriorated the quality of fish, rendering their products unfit for human consumption. The process of odour removal requires purification for several days to weeks in clean water; thus this leads to additional production costs. Geosmin and 2-MIB, detected at extremely low odour thresholds, are the most widespread off-flavour metabolites in aquaculture, entering through fish gills and accumulating in the fish adipose tissues. In this review, we aimed to determine the diversity and identity of geosmin- and 2-MIB-producing bacteria in aquaculture and provide possible strategies for their elimination.

The rise in the use of single-use plastics and personal protective equipment (PPE) has increased plastic waste in the marine environment. In this study, we surveyed the presence of PPE (face masks and gloves) discharged in 6 beaches along the coast of India. A total of 496 PPE were counted with an average density of 1.08 × 10⁻³ PPE m⁻². The PPE density found was comparable to previous studies. Face masks were the most recorded type of PPE (98.39%), with gloves accounting for only 1.61% of the total. However, a significant reduction in the appearance of PPE was recorded on all six beaches, likely due to the increase in vaccination rates. The most contaminated places were the beaches with recreational activities + fishing. It has been noticed that the lack of awareness of environmental pollution and the negligence of the population and the mismanagement of municipal waste are the main causes of beach pollution by PPE. This study confirms the potential threat of PPE to terrestrial and aquatic organisms of multiple taxa in India, but further studies are needed to quantify the impact of this type of waste on marine animals.

The presence of microplastics in the world's oceans and their effects on marine habitats are highly concerning. As suspension-feeders, corals are very exposed to microplastics, compromising the health of coral reef ecosystems. In this study we surveyed for the first time the presence of microplastics in Maldivian reef-building corals. Aiming to determine the influence of exposure and depth on microplastic distribution, analyses were carried out on 38 individuals belonging to three different species. 58% of the investigated colonies resulted contaminated with particles within the 25–150 μm size range. The maximum concentration was encountered in a Pocillopora verrucosa colony sampled from a shallow inner reef (8.9 particles/g of coral). No significant differences in microplastic concentration were observed between different depths, exposures, sites and species. Overall, this study confirmed microplastic presence in coral reefs of the Maldivian archipelago including foundation species.