The coastal pollution has been evaluated using indexes like Clean Coast Index (CCI) in many countries. In this study, several coasts and urban areas in northern of Iran along the Caspian Sea, were assessed in terms of number and composition of litters. Furthermore, Clean Environment Index (CEI) was used for the first time to interpret the results. The results indicated that 60% of the coasts and 50% of the urban areas were in a dirty status and only 22% of the total surveyed areas were found to be in a clean status. The highest number of litters observed in the study areas was cigarette butt. Due to the impact of risk factor of different types of littered waste, it was obviously clear that CEI offers a more realistic and rigorous interpretation than CCI. Therefore, this new index can be considered to evaluate litters pollution in various areas.

This study aimed to investigate the toxicity of innovative antifouling nanostructured biocides DCOIT and silver associated to silica nanocapsules (SiNC) on the tropical microcrustacean Mysidopsis juniae. The toxicity of the tested compounds can be summarized as follows (acute tests): DCOIT > SiNC-Ag > SiNC-DCOIT > SiNC-DCOIT-Ag > SiNC > Ag; (chronic tests): SiNC-Ag > SiNC-DCOIT-Ag > DCOIT > Ag > SiNC, although it was not possible to determine the chronic toxicity of SiNC-DCOIT. In general, our data demonstrated that mysids were more sensitive than most temperate species, and it was possible to conclude that the combination SiNC-DCOIT-Ag showed less acute toxicity in comparison to the isolated active compounds, reinforcing data obtained for species from temperate environments on the potential use of nanomaterial to reduce toxicity to non-target species. However, despite representing less risk to the environment, the compound SiNC-DCOIT-Ag is still very toxic to the non-target tropical mysid.

PURPOSE OF REVIEW: This review is focused on the removal of chlorinated hydrocarbons (as representative of persistent pollutants) from soil by soil-washing techniques, paying special attention to the application of electrochemically assisted technologies for the treatment of the liquids and gases produced during this treatment. It considers the degree of maturity of the technologies and suggests challenges for future research. RECENT FINDINGS: Electrochemical technologies can help to improve the overall efficiency of soil washing processes in the removal of chlorinated hydrocarbons, contributing to the depletion of these hazardous species from the soil washing liquid and gaseous effluents generated during the treatment of the soil. Chlorinated hydrocarbons are a good example of persistent organic pollutants which can be found in very high concentrations in polluted soil, especially in industrial sites. Because of its fast action, soil washing can be efficient for preventing the spread of chlorinated hydrocarbons after accidental spills. Recent progress about fundamentals of this process and key parameters involved is discussed at the light of competing technologies, paying special attention to the liquid and gaseous wastes produced during this treatment, in the search of holistic approaches. Among the different alternatives proposed, electrochemical technologies are the focus of attention of many researchers and, because of that, recent progress in electrochemical technologies capable to deplete the pollutants is also discussed, within a comparison context with other competing technologies, indicating the technology readiness level of each electrochemical process and the challenges that must be overcome in order to reach full-scale applicability.

Macrocystis pyrifera reaches distant areas after detachment, accumulate heavy metals, and serve as trophic subsidy. In this context, effects on both adults and larvae of Tetrapygus niger fed with polluted kelps were determined by assessing growth, fertility, and early larval development. Results revealed that sea urchins fed with polluted kelps from highly impacted zone (HIZ) showed a lower growth (3.6% gained weight) and gamete release (358 cells mL⁻¹) than those fed with non-impacted kelps (NIZ) (19.3% and 945 cells mL⁻¹). The HIZ treatment showed a developmental delay in comparison to NIZ, accounted mainly by the abundance of malformed 2-arm pluteus larvae (10–15%) during most of the culture. Malformed 4-arm pluteus larvae showed a constant increase, reaching 37% at the end of the culture. Thus, the pollutants ingested by sea urchins can be transferred to their offspring and cause negative effects in their early development, categorizing M. pyrifera as a pollutant carrier.

Controversy remains on the use of Sub-Sea Dispersant Injection (SSDI) during the Deepwater Horizon (DWH) spill to minimize the exposure of responders on surface vessels to volatile organic compounds (VOC). Here, we use extensive evidence (>90,000 VOC measurements) collected near the oil well MC252 site during the DWH spill and demonstrate at a high level of statistical confidence that SSDI enhanced the safety and health conditions of the responders at the water surface through the reduction of airborne VOC concentrations in a dose-dependent manner. VOC levels on ships' decks were clearly diminished (p < 0.001) during subsea dispersant use, and incidents of peak concentrations (>50 ppm VOC) that could have been an immediate concern to worker health were reduced by a factor of ~6 to 19 when dispersants were delivered at the intended rate. SSDI thus played an important role in minimizing potential exposure to VOC, and should be embedded in guidelines and regulations for dispersant use.

Despite exponential growth of anthropogenic marine debris in recent decades, plastic ingestion by marine turtles in the Gulf of Mexico is not well understood. Gastrointestinal tracts were examined from 464 green turtles that stranded in Texas between 1987 and 2019, and 226 turtles ingested plastic (48.7%). This number doubled from 32.5% in 1987–1999 to 65.5% in 2019, but mass of ingested items was lowest in 2019. No turtles showed evidence of death directly related to plastic ingestion. Compared to other regions, plastic ingestion was low. Small turtles (<25 cm straight carapace length) ingested plastic more frequently and in greater amounts than larger turtles. Small turtles also ingested more hard plastic while larger turtles ingested more sheet-like and thread-like plastics, which may correspond to size-based habitat shifts. This is among the largest marine turtle ingestion studies to date and demonstrates an increasing prevalence of plastic ingestion.

Ecological concrete (eco-concrete) can reduce excess nutrients (nitrogen and phosphorus) in water, but its effectiveness in removing nutrients in marine coastal sediments and the response of sediment microbial communities to its use are largely unknown. In this study, eco-concrete planted with Bruguiera gymnorrhiza was used to remove nutrients in marine coastal sediment. We found that the mean removal efficiencies of sediment total nitrogen and total phosphorus by using planted eco-concrete were 11.50% and 30.31% on day 60, and were higher than those obtained by only using B. gymnorrhiza (7.14% and 7.36%). the Diatoms and bacterial genera Fusibacter and Anoxynatronum (which belong to Firmicutes) increased and became the abundant microbes by day 60 when using planted eco-concrete, indicating their potential roles in nutrient removal. Moreover, the eco-concrete did not endanger the core microbes in sediment suggesting its environment-friendly character. Our results suggest a potential method to control marine coastal eutrophication.

The Japanese government approved a plan to discharge Fukushima Daiichi Nuclear Power Plant Accident contaminated water (FDNPPACW) into the Pacific Ocean. It immediately caused a new wave of global concern and anxiety. To assess this matter, this work briefly reviewed the dispersion of FDNPPA-derived radionuclides in the Pacific Ocean in the past and the resulting impacts on marine biota. Combining the drafted plan of discharging FDNPPACW and the public's concerns, 5 points, including (1) the detailed plan of discharging FDNPPACW, (2) the isotopes left in the advanced liquid processing system (ALPS)-treated water and their amounts, (3) the stability of the Kuroshio Extension, (4) the fates and transports of the main radionuclides (left in the ALPS-treated water) in North Pacific seawater, (5) and bioaccumulations and the ecological half-lives of the main radionuclides (left in the ALPS-treated water) in marine biota in the North Pacific, remain to be known to understand the impacts of discharging FDNPPACW into the Pacific Ocean.

The principal objective of this study is to assess the saltwater intrusion and hydrogeochemical processes that affect groundwater geochemistry in the coastal aquifers of southwestern India. Groundwater samples were collected seasonally and the physico-chemical parameters determined on-site. Major ions were determined in the laboratory. Hydrochemical diagrams, ionic ratios, and multivariate statistical analysis were adopted for understanding the groundwater chemistry. Gibbs plot identified that rock-water interaction and evaporation were the mechanisms regulating hydrogeochemistry. Ionic ratios have shown that coastal wells were contaminated with saltwater intrusion during the pre-monsoon season. Hierarchical cluster analysis classified the samples based on their quality; sample clusters with high NO₃⁻ were in densely populated areas, whereas sample clusters with moderate salt content in the coastal areas. Another cluster showed high concentrations of salts, typically the zones of saltwater intrusion. The study concludes that influence of seasons, geogenic and anthropogenic factors contribute to the heterogeneous chemistry of groundwater.

While the Mediterranean coastal region of the Nile Delta is critical socioeconomically, it is under significant environmental stress due to the growing load from diverse land-based activities. This study examines the fluctuations in the concentrations of several minerals in sediments from depths ranging from 10 to 50 m. This study is considering the first work that carries the identification of different minerals by using two different techniques: Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction technique (XRD), in this area. At the same time, the particle size was also assessed. The particle size analyzer (PSA) results showed that the grain size analyses in the sediments varied between slightly gravelly sand, slightly gravelly mud, and silty sand. Mineral identification using FTIR and XRD analysis proved that some minerals such as aragonite, calcite, quartz, kaolinite, montmorillonite, albite, muscovite, and microcline have been presented in most of the studied locations.