Oil spills at sea pose a serious threat to coastal environments. Identifying oil pollution sources could help to investigate unreported spills, and satellite imagery can be an effective tool for this purpose. We present a Bayesian approach to estimate the source parameters of a spill from contours of oil slicks detected by remotely sensed images. Five parameters of interest are estimated: the 2D coordinates of the source of release, the time and duration of the spill, and the quantity of oil released. Two synthetic experiments of a spill released from a fixed point source are investigated, where a contour is fully observed in the first case, while two contours are partially observed at two different times in the second. In both experiments, the proposed method is able to provide good estimates of the parameters along with a level of confidence reflected by the uncertainties within.

Constant evolution of omics-technologies has provided access to identification of various important gene families. Recently, genome assemblies on widely used ecotoxicological model species, including rotifers and copepods have been completed and representative detoxification-related gene families have been discovered for biomarker genes. However, despite ubiquitous presence of stress-response proteins, limited information on full genome-wide report on heat shock proteins (Hsps) is available. Various studies have demonstrated multiple cellular functions of Hsps in living organisms as an important biomarker in response to abiotic and biotic stressors, however, full genome-wide identification of Hsps, particularly in aquatic invertebrates, has not been reported. This is the first study to report the entire Hsps and basal gene expression levels in three regional-specific copepods: Tigriopus japonicus and kingsejongensis, Paracyclopina nana, and Eurytemora affnis, and how each Hsp family gene is regulated at a basal level.

There is a concern that the Fly River plume from Papua New Guinea (PNG) may be delivering mine-derived polluted mud along the southern PNG coast into the northern Torres Strait, which is the northernmost extent of the Great Barrier Reef. To quantify this threat, the mud transport dynamics along the southern PNG coast were studied using the SLIM model. The model was qualitatively verified using historical field data on sediment dynamics and compared with more recent satellite-derived turbidity data. During strong south east winds and spring tides, about 5.4% of the Fly River mud discharge enters the Torres Strait, in agreement with previous field-derived results. The annual net movement of mud is westward, thus polluted Fly River mud progressively intrudes into Torres Strait. This intrusion is slow and may take a century to reach in significant quantities at Saibai Island, the nearest Australian island to the Fly River. Field data are needed to fully validate the model and provide greater confidence in these results.

A forensic source evaluation of polycyclic aromatic hydrocarbons (PAHs) in nearshore sediments in San Francisco Bay examined total PAH greater than ambient concentrations in sediments, and potential pyrogenic source relationships with respect to PAH compounds typically associated with point and nonpoint pyrogenic source types, including PAHs potentially associated with historical manufactured gas plant (MGP) operations. Diagnostic source ratio analysis was employed for determination of potential PAH source relationships. A two-model approach indicated distinct potential source signatures, as identified from the distributions of higher PAH concentrations in some sediments. Source characterization was aided by Polytopic Vector Analysis (PVA) and data visualization with t-Distributed Stochastic Neighbor Embedding (t-SNE). Two signatures exhibited pyrogenic character likely consistent with historical MGP sources, and one signature was related to creosote. A distinct and significant source of PAHs to the investigation area sediment consisted of ubiquitous nonpoint and potential unidentified point sources is termed “urban influence”.

The contamination by antifouling biocide residues (booster biocides - diuron, Irgarol, chlorothalonil, dichlofluanid and DCOIT; butyltin compounds-BTs (TBT, DBT and MBT); and antifouling paint particles-APPs) was appraised in sediments of Vitoria Estuarine System (VES). Even at its historical lower (ΣBTs ≤113 ng Sn g⁻¹ dry wt), the current environmental levels of BTs in areas with a predominance of boatyards still pose a risk to the local biota and human population. DCOIT, among booster biocides, was the most frequently detected, especially in boatyards (≤40 ng g⁻¹ dry wt) and Vitoria Port (64 ng g⁻¹ dry wt), while APPs were also detected mainly in sediments of boatyards (≤5,969 μg g⁻¹ dry wt). Since levels of diuron and DCOIT in APPs were as high as 1,670,000 and 899,000 ng g⁻¹ dry wt, respectively, they are acting as secondary sources of these antifouling biocides. Therefore, VES is threatened by antifouling biocide residues due to the multiple diffuse sources of contamination, showing the need for more efforts on public policies (including temporal trend monitoring studies).

A webcam was installed on the shore of the South-Eastern Baltic (Kaliningrad Oblast, Russia) to monitor the beach dynamics and beach-cast (BC) daily from November 1, 2019, to October 31, 2020. The beach was formed not the whole year (77%). The most frequent BC residence time was one day (1–21, 4.1 on average, and 1–19, 4.3 on average days to the west and east of the groin, respectively). The BC consisted primarily of algae. Fresh BC occupied smaller area, and its layer was thicker than that of long-discarded and trampled BC. The specific amount of material (per m²) in a fresh BC was 3.7 times higher in volume and 2.6 times higher in weight than in long-discarded and trampled BC. For fresh and old BC, the specific volumes were 63 and 17 l per m², respectively, and the specific masses were 48 and 18 kg per m², respectively.

Sampling was conducted in Port Valdez, the site of the Valdez marine oil terminal where crude oil is loaded onto tankers for ocean shipment, to characterize sediment polycyclic aromatic hydrocarbons (PAH) concentrations arising from discharge of treated ballast-water from 1989 to 2019. Sediment PAH concentrations have declined since 1991 due to technological improvements in ballast water treatment processes and reductions in the volume of water treated. Spatial variations are associated with water depth reflecting geological and oceanographic characteristics. Comparisons between uncorrected hydrocarbon (compatible with data from 1989 to 2002) and surrogate-corrected concentrations for 2003–2019 suggest minor influence by corrections on inferences. It appears that if reliable measurements are made, the number of analytes and surrogate corrections have minimal influence for characterizing the directions and strengths of spatial and temporal change like that observed in Port Valdez. At present, PAH concentrations in the study area represent low risk for ecological effects.

Accurate source identification is the first step of pollution control in environmental emergency management, especially in marine pollution events. Dissolved organic matter (DOM) absorption and fluorescence (excitation-emission matrices, EEMs) analyses were applied to trace contaminant sources for a pollution event that occurred along the coast of Laizhou Bay, Bohai Sea. Parallel factor analysis (PARAFAC) of the EEMs identified four fluorescent components: terrestrial humic-like (C1), tryptophan-like (C2), and a mixture of terrestrial and marine humic-like (C3) and tyrosine-like (C4) components. The relationships among C1 to C4 and quality indices indicated that the DOM originated from terrestrial input and biological activity. The EEMs-PARAFAC results accompanied by the optical characteristics of DOM and fingerprinting demonstrated that the marine pollution event occurred was from enterprise emissions. The numerical simulation confirmed the reliability of EEMs-PARAFAC modeling for DOM fingerprinting of pollution sources in polluted regions. This study provided a feasible method for source recognition in marine pollution events.

This study aimed to develop a first diagnostic of marine litter presence over four sandy beaches located on the southern coast of Sergipe, a Brazilian state, by means of four samplings, from December 2017 to September 2018. There was no distinction between village, semi-rural, and rural areas regarding litter presence. Plastic was the most abundant litter (> 70%), mainly represented by the items such as food packaging, cups, straws, cigarette butts, lids/seals, as well as fragments and monofilaments. The abundance of items collected ranged from 0.1 and 9.2 items.m⁻¹, and the beaches were characterized from very clean to dirty. The main sources were from tourism/recreation (42.7 ± 4.8%), followed by Unidentified (34.1 ± 6.7%), and Fishing/Marine activities (16.1 ± 6.3%). In addition, we highlight the importance of the correct litter management, environmental education activities, and marine litter monitoring program in order to reduce marine litter contamination.