The establishment of water quality criteria (WQC) for oil pollutants is the basis for ecological risk assessment of marine oil pollution. Ecotoxicity data of oil pollutants to marine organisms in China were collected and toxicity test of oil to nine Chinese marine organisms were performed. Based on the WQC guidelines of the United States, the sea WQC of oil pollutants in China were studied. Then, the ecological risk of oil in 7 sea areas of China was assessed. Results showed that the long-term and short-term criteria of oil pollutants in China are 7.3 μg/L and 36 μg/L, respectively. Except for Qinhuangdao and Xiamen sea areas, the highest oil concentration in the other five sea areas exceeded the long-term WQC by >10 times, and the highest oil concentration in the Pearl River Estuary exceeded the long-term WQC by >100 times, indicating serious ecological risk.

Total mercury (THg) and δ¹⁵N were analysed in liver and muscle of juvenile green turtles (Chelonia mydas) from a foraging site in southeastern Brazil (~23°S) to evaluate contamination levels and make inferences about the timescale that animals were recruited from oceanic to coastal waters. The values for THg and δ¹⁵N in liver and muscle were 432.2 and 72.8 μg kg⁻¹ and 10.0‰ and 9.2‰, respectively. THg concentrations in tissues indirectly indicated that the main food resources for this consumer (i.e., macroalgae) had negligible levels of this element. Thus, this foraging site could be considered a pristine area in terms of Hg contamination. The THg and δ¹⁵N in liver were derived by more recent food ingestion than those in muscle. The juvenile green turtles that died because of incidental captures in fisheries practiced along this foraging site were individuals newly recruited from oceanic waters.

Effective site selection is a key component of maximising debris removal during coastal cleanup actions. We tested a GIS-based predictive model to identify marine litter hotspots in Lofoten, Norway based on shoreline gradient and shape. Litter density was recorded at 27 randomly selected locations with 5 transects sampled in each. Shoreline gradient was a limiting factor to litter accumulation when >35%. The curvature of the coastline correlated differently with litter density at different spatial scales. The greatest litter concentrations were in small coves located on larger headlands. A parsimonious model scoring sites on a scale of 1–5 based on shoreline slope and shape had the highest validation success. Sites unlikely to have high litter concentrations were successfully identified and could be avoided. The accuracy of hotspot identifications was more variable, and presumably more parameters influencing litter deposition, such as shoreline aspect relative to prevailing winds, should be incorporated.

In this article we compare the efficiency of different methods of rapid-response remediation of beach sand contaminated with microbiological and/or organic matter. Contaminated beach sands were treated in laboratory by different treatment methods (i.e., oxidation, UV-photoexposure, or thermal methods) and the efficiency of disinfection and breakdown of organic matter were evaluated. Contaminants in raw and treated beach sands were measured by membrane filtration method, and by chemical and biochemical oxygen demand, and chromatographic analysis. All the methods tested were efficient for disinfecting beach sand with microbiological contamination, except for the UV-photoexposure method, which showed only moderate disinfection potential. Chemical degradation efficiency of beach sand contaminated by crude petroleum was higher with Fenton and Photo-Fenton (associated with the use of surfactant and ultrasound) methods. Photo-Fenton method improvement can increase the efficiency of contaminated beach sand treatment, and can also help beach managers when selecting which method to adopt for remedial actions.

The vaquita (Phocoena sinus) is the world's smallest cetacean and most endangered marine mammal. The species is under threat from illegal fishing activities that take place in the upper Gulf of California (UGC). Artisanal use of gillnets to catch shrimp and poach the endangered totoaba are the primary drivers of vaquita population declines due to bycatch. About 80% of shrimp caught in the UGC is sold to the United States, meaning Americans who consume shrimp may have a direct connection to the plight of the critically endangered vaquita. However, this issue as part of the human dimensions of vaquita conservation has been largely unstudied. Additionally, the majority of Americans are unfamiliar with the vaquita which hinders conservation efforts. This article calls for further research into the human dimensions of vaquita conservation, increased collaboration with fishing communities in the UGC, and connecting seafood sellers and consumers with the vaquita crisis.

Environmental conditions and xenobiotic exposure can be sources of stress to living organisms. Biological markers are measurable indicator of changes which may happen at any biological level and which can be considered an early warning signal of some biological or environmental state or condition. A structured field study was undertaken to investigate the relationship between three biomarker assays and the spatial and temporal variation of each biomarker in samples of Mytilus edulis. The three biomarkers were the neutral red retention assay, micronucleus assay and comet assay, which indicate damage at different cellular/molecular levels. Three sites in Poole Harbour, an area on the South coast of the UK were sampled on six separate occasions at least three weeks apart. The results for the comet assay showed a significant difference between sites and between sampling dates whereas the results for the other two assays did not show a significant difference for either factor. There was no significant correlation between the results of any pair of the three biomarkers. The results of the micronucleus assay showed a significant correlation with water temperature. This temperature effect, as well as induced repair, may contribute to explain the lack of a strict correspondence between pollution gradients and biomarkers responses.

Environmental concentrations of Pb have been increased due to anthropogenic activities, which have provoked the released of this element to the environment in large amounts. To understand how Pb behaves in remote southern marine ecosystems, we measured Pb concentrations and isotope ratios in biota from coastal marine ecosystems of the Chilean Patagonia and the Antarctic Peninsula area. Lead concentrations in the aquatic organisms ranged from 0.02 to 1.19 mg kg−1 d.w. In Patagonia, higher Pb levels were found in fish than in invertebrates (crab, shrimp, porifera, limpet and shellfish). In comparison with the baseline reference values from other parts of the world, fishes exhibited lower Pb levels. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in marine organisms come from different anthropogenic sources. These Pb levels might be useful for further studies that allow a deeper evaluation of sources for Pb contamination in these remote ecosystems.

Vessels, specifically ballast water and hull fouling, are a major vector for the introduction of non-indigenous species (NIS) in European seas. The Mediterranean is one of the world's marine regions where their invasion is heaviest. The shallow Adriatic basin is a highly sensitive area that is already experiencing its consequences. The secondary spread of NIS over a wider area through natural dispersion is a complex process that depends on a wide range of oceanographic factors. This work analysed the dataset of the BALMAS project, in whose framework twelve ports in the Adriatic Sea were subjected to a Port Baseline Survey (PBS), to estimate the natural spread of NIS organisms from their port of arrival to the wider Adriatic basin. Its findings indicate that the prevailing water circulation patterns facilitate the natural dispersal of harmful aquatic organisms and pathogens (HAOP).

The bioaccumulation and the main source of total Hg (THg) and methylmercury (MMHg) in the deposit-feeding polychaete Neanthes japonica collected in Jinzhou Bay, China, were investigated. Compared with the historical data, THg bioaccumulation in polychaetes collected in sediment of Jinzhou Bay was distinctly higher due to higher sediment THg concentration, but MMHg bioaccumulation was significantly lower. THg accumulation in polychaetes mainly derived from its accumulation in sediment. However, MMHg bioaccumulation in polychaetes did not correlate with Hg concentration in sediment. Besides sediment ingestion, MMHg accumulation in polychaetes may partially source from the process of in vivo transformation. The in vivo Hg methylation may take place in polychaetes, according to the excellent correlation between MMHg concentration and THg and inorganic Hg concentration in polychaetes. The biochemical characters in polychaete body, the oxidation-reduction environment and the microbial activity in polychaete gut may be beneficial to in vivo Hg methylation.

The aim of this research was to assess the impact of hydrotechnical works within the riverbed and riparian zone on the mobility of mercury in soil and its outflow to the river and the sea. Deepening and reconstruction of the riverbed or the cutting of reeds, influenced the fate of mercury in the river system. However, only activitis that disturbed the riperian zone increased mobilization of Hg in soils. Hg transformations in these places were controled by inflow of fresh organic matter in soil and sediments as well as by oxidation-reduction potential. In areas where reducing conditions occurred, mercury released from the soil was incorporated into the sediment. However, in areas where oxidizing conditions prevailed in the sediment, mercury flowing out of the soil occurred mainly in dissolved form and most of it was transported downstream from where it could reach the sea.