Deep-sea fish from the Arabian Sea in the south western coast of India have been gaining attention as a new edible fish source. Mineral profile of ten selected deep-sea fish from the south west coast of India were assessed for heavy metal and macro mineral content for safety and nutritional quality assessment, respectively. Heavy metal levels were below permissible limits for most of the species studied. But in some species, the levels slightly exceeded the permissible limit of 0.3 mg/kg for Pb, a major heavy metal contaminant in fish, according to the European Union and FSSAI regulations for heavy metals in food. Interestingly, significant content of macro minerals was observed in all the species studied. In conclusion, deep-sea fish were observed to be good source of minerals and were found to be safe for human consumption; except for a couple of species which possess slightly higher Pb content, which may be because of its presence in their habitat.

Microplastic (MP) pollution is a matter of great concern attracting increasing attention due to its adverse effects on the environment. Different technologies and methodologies have been developed to remove these pollutants. Herein, we focus on a promising environmental solution that involves surface modification to change the wettability properties of MPs or solid materials by conferring superhydrophobicity and superoleophilicity to increase the selectivity for MP separation. Both processes can be used to selectively separate MPs because of the changes in the wettable properties of the MP or by changing the oil used in the case of superhydrophobic surfaces. We show two distinct methods based on changing the wettability properties of surfaces that could lead to innovative and environmental applications. We also discuss some of the challenges that need to be overcome.

The grain size and heavy metals (Cu, Pb, Zn, Cr, Cd, and Hg) in 42 seafloor and eight river sediments from the Kompong Som Bay of Cambodia were analyzed to identify sediment characteristics and environmental quality. The high-value areas for all the metals were mainly distributed in the northern and central parts of the bay, occupied by fine-grained sediments. There was slightly to moderately severe enrichment of Pb, Cd, and Hg in the southern and western coastal areas of Sihanoukville. Although the current ecological environment risk was relatively low, the coastal areas of Sihanoukville had low to moderate pollution of Pb, Cd, and Hg, which were closely related to pollutant emissions from the industrial production from power plants and oil refineries. It is recommended to establish a normalized monitoring mechanism and control the discharge of coastal pollutants to ensure the sustainable development of the coastal environment.

Stakeholders' understanding of water quality influences how they approach water policy problems and their support for potential solutions. This study explores how resource policy in the United States accounts for different water quality meanings held by recreational users. In-person surveys were conducted along the shoreline in Rhode Island (USA) to examine how recreational users make sense of coastal water quality. Findings indicate that recreational users' understanding of water quality is constructed from an array of environmental conditions (e.g., chl a, phosphates) and attitudinal factors (e.g., perceived problems associated with sewage, algae, or trash), and the meanings ascribed to water quality extend beyond the biophysical indicators typically employed by water resource managers. Potential management strategies based on these findings include expanding current definitions of water quality and monitoring a broader suite of factors, conducting research that captures nuanced meanings of water quality held by different users, and developing outreach programs that clarify the potential impacts of water quality components on human health and well-being.

The Quality Ratio (QR) index was applied in Sepetiba Bay to integrate geochemical and microbiological parameters of the in situ microbial community in order to classify the ecological risk of sediments. Total concentrations (C) of Hg, Cd, As, Pb, Cr, Cu and Zn (indicators of the mixture of contaminants) were determined at 26 stations and at a background area (C₀) to calculate the contamination factor (CF = C/C₀) and the degree of contamination (ΣCF). Enzymatic biomarkers of energy production into cell (dehydrogenase - DHA) and hydrolase of organic matter outside the cell (esterases - EST) were determined. The QR, a function of the microbial term (DHA/EST) and the geochemical term (TOC × ΣCF/fine-grained content), was able to segregate stations into the internal sector (east of the bay with the largest continental contributions) and the external sector (west of the bay), proving its accessibility (low-cost and fast) and efficiency for assessing ecological risk.

To evaluate the heavy metal contamination, ecological risk and possible sources at Saudi Yanbu coastline, 30 sediment samples were collected for Fe, Pb, Ni, As, Zn, Cu, Cr, Co, Al, Sb, Cd, and TOC analyses using ICP-MS. The potential ecological risk index (PERI), enrichment factor (EF), contamination factor (CF), potential contamination index (Cp), geoaccumulation index (Igeo), soil pollution index (SPI) were calculated and interpreted, and multivariate analyses were applied. The results indicated the following order for metal averages: Al (8573 μg/g) > Fe (5895 μg/g) > Mn (192 μg/g) > Zn (80.4 μg/g) > Cu (35.87 μg/g) > Cr (27.11 μg/g) > Ni (23.5 μg/g) > Co (8.29 μg/g) > Pb (7.72 μg/g) > As (6.83 μg/g) > Sb (0.50 μg/g) > Hg (0.33 μg/g) > Cd (0.30 μg/g). Average levels of As, Ni, Zn, Co, Cd, and Pb values were greater than those reported from many coastal sediments from the Red Sea, Gulf of Aqaba, Arabian Gulf and Mediterranean Sea, as well as the sediment quality guidelines. The results of potential ecological risk revealed very high risk for Cd, high risk for Hg, considerable risk for Cu, Sb, and As, moderate risk for Pb and Ni, and no to low risk for Zn and Cr. The moderately severe enriched HMs (Cd, Zn, Cu, Hg) and the moderate enriched ones (Pb, Co, As) were originated mostly from anthropogenic sources related to industrial, agricultural, urbanization and fishing activities. The no and minor enriched HMs (Fe, Al, Ni, Cr, Sb) were mostly related to lithogenic factors related to rock weathering and atmospheric inputs.

The cultivable fungal diversity from PAH-contaminated sediments was examined for the tolerance to polycyclic aromatic hydrocarbon (PAH). The 85 fungal strains, isolated in non-selective media, revealed a large diversity by ribosomal internal transcribed spacer (ITS) sequencing, even including possible new species. Most strains (64%) exhibited PAH-tolerance, indicating that sediments retain diverse cultivable PAH-tolerant fungi. The PAH-tolerance was linked neither to a specific taxon nor to the peroxidase genes (LiP, MnP and Lac). Examining the PAH-removal (degradation and/or sorption), Alternaria destruens F10.81 showed the best capacity with above 80% removal for phenanthrene, pyrene and fluoranthene, and around 65% for benzo[a]pyrene. A. destruens F10.81 internalized pyrene homogenously into the hyphae that contrasted with Fusarium pseudoygamai F5.76 in which PAH-vacuoles were observed but PAH removal was below 20%. Thus, our study paves the way for the exploitation of fungi in remediation strategies to mitigate the effect of PAH in coastal marine sediments.

PURPOSE OF REVIEW: During the nineteenth and twentieth century, production and usage of plastic material have increased and led to a serious problem for their non-degradable property, persistence in the environment. Natural factors act on plastic material fragmented into microplastics. Entering of microplastics causes threats to all ecosystems and their organisms. In this urgent need, this review summarizes (1) sources and transport of microplastics into aquatic ecosystems, (2) ecological impacts of microplastics in aquatic biota and their environment, (3) bacterial remediation of environmental microplastics and (4) mechanism involved bacterial remediation. RECENT FINDINGS: The terrestrial biosphere serves as a major hub for microplastic wastes and it has been settled in the aquatic ecosystem through the improper disposal methods of human beings. The aquatic biota attains severe effects such as reduced food consumption, fecundity and triggered inflammation; moreover, microplastics ingestion leads to changes in physical, chemical, and gene levels of aquatic organisms. Hence, it is an urgent need to prevent further entry of microplastics (from origin) and eliminate the persisted microplastics in the environment. Recently, researchers are trying to use bacterial strains for microplastics degradation as an eco-friendly and more safe method because during degradation the daughter metabolites carbon dioxide, methane, and water will be produced. Microplastics are a major concern pollutant in earth. Unfortunately, ingestion of microplastics in each trophic organisms via the food chain. In this situation, eradicating the environmental microplastics through an eco-friendly approach using bacteria is a effective remediation technique. Furthermore, research needed using different formulations including bacteria and their based components, consortium of bacteria have enhanced the efficacy of degradation.

In the current study, 16 congeners of PAHs were measured in 32 surface sediment samples to determine their pollution status in the Jiangsu coastal zone, East China. The total concentrations of the 16 PAHs ranged from 2.2 to 46.6 ng g⁻¹ with an average of 8.36 ng g⁻¹ in surface sediments and were significantly lower than those of PAHs in other coastal areas of China. The spatial distribution of PAHs revealed an increasing trend from nearshore to offshore, controlled by the regional sedimentary dynamic environment. Diagnostic ratios and positive matrix factorization demonstrated that petroleum, industries, biomass and coal combustion, and marine and vehicular traffic sources contributed to 28.9%, 25.5%, 24.7%, and 20.9% of the total PAHs, respectively. Risk assessment suggested that the carcinogenic risks were <1 × 10⁻⁴ for all age groups in the area, indicating that long-term seafood consumption does not pose a significant cancer risk in this area.

The acute toxicity of nitrofurazone on community functioning was studied using an acute toxicity test. Consequently, 14-day protozoan periphyton assemblages were used as test organism communities, under a range of nitrofurazone concentrations including 0 (control), 0.5, 3, 6, and 12 mg ml⁻¹ within 0, 2, 4, 6, 8, 10, and 12 h time duration. Fuzzy coding system of functional traits classified the test protozoan periphyton community into six major traits and 15 categories. Briefly, community-weighted means (CWM) were used to identify the community functioning of test protozoan assemblage. Inferences demonstrate a drastic/significant variation in the functional patterns of the test organisms at a high concentration (12 mg ml⁻¹) after an exposure time of 12 h, but the functional diversity indices leveled off at the exposure time of 10 h and then dropped sharply. These results suggested that nitrofurazone may significantly influence the community functioning in marine ecosystems.