Polycyclic Aromatic Hydrocarbons and Polychlorinated Biphenyls in Seawater, Sediment and Biota of Neritic Ecosystems: Occurrence and Partition Study in Southern Ligurian Sea

Brominated flame retardants in Caretta caretta sea turtles from the Adriatic Sea

This study evaluated the levels of 10 polybrominated diphenyl ethers (PBDEs) and 3 hexabromocyclododecanes (HBCDDs) in liver and fat tissue of 45 Caretta caretta stranded along the Adriatic Sea. The analytical methodology was based on gas or liquid chromatography coupled with high-resolution mass spectrometry. The mean values of PBDEs and α-HBCDD were 0.83 ± 0.39 and 0.069 ± 0.10 ng g-1 w.w. in liver, while 2.54 ± 0.80 and 0.56 ± 0.47 ng g-1 w.w. in fat tissue, respectively. The levels were higher in fat tissue than in liver. The PBDE profile was similar to that found in aquatic species while for HBCCDs, only the α-isomer was detected. No correlation between the contamination levels and sex and size was found. This study adds information about contamination levels of some brominated compounds in C. caretta, providing a background level in liver and fat tissue of loggerhead sea turtles from the Adriatic Sea.

Biofilm formation and EPS production enhances the bioremediation potential of Pseudomonas species: a novel study from eutrophic waters of Dal lake, Kashmir, India

The present study was conducted with the aim of isolation and identification of the biofilm-forming denitrifying Pseudomonas bacterial strains from eutrophic waters of Dal lake, India, followed by the study of inter-relation of biofilm formation and denitrification potential of Pseudomonas strains. The bacterial strains were characterized by morphological observations and identified using 16S rDNA sequencing followed by the quantification of biofilm formation of these st by crystal violet (CV) assay using 96-well microtiter plate and extracellular polymeric substance (EPS) extraction. Lastly, the nitrate-reducing potential of all Pseudomonas species was studied. Our evaluation revealed that four different Pseudomonas species were observed to have the biofilm-forming potential and nitrate-reducing properties and the species which showed maximum biofilm-forming potential and maximum EPS production exhibited higher nitrate-removing capacity. Moreover, P. otitis was observed to have the highest denitrification capacity (89%) > P. cedrina (83%) > P. azotoform (79%) and the lowest for P. peli (70%). These results clearly signify a positive correlation of biofilm-forming capacity and nitrate-removing ability of Pseudomonas species. This study has for the first time successfully revealed the bioremediation potential of P. otitis, P. cedrina, P. azotoform, and P. peli species, thus contributing to the growing list of known nitrate-reducing Pseudomonas species. Based upon the results, these strains can be extrapolated to nitrate-polluted water systems for combating water pollution.

Effective microorganism water treatment method for rapid eutrophic reservoir restoration

Since reservoirs perform many important functions, they are exposed to various types of unfavorable phenomena, e.g., eutrophication which leads to a rapid growth of algae (blooms) that degrade water quality. One of the solutions to combat phytoplankton blooms are effective microorganisms (EM). The study aims to evaluate the potential of EM in improving the water quality of the Turawa reservoir on the Mała Panew River in Poland. It is one of the first studies providing insights into the effectiveness of using EM in the bioremediation of water in a eutrophic reservoir. Samples for the study were collected in 2019-2021. The analysis showed that EM could be one of the most effective methods for cleaning water from unfavorable microorganisms (HBN22, HBN36, CBN, FCBN, FEN) - after the application of EM, a reduction in their concentration was observed (from 46.44 to 58.38% on average). The duration of their effect ranged from 17.6 to 34.1 days. The application of EM improved the trophic status of the Turawa reservoir, expressed by the Carlson index, by 7.78%. As shown in the literature review, the use of other methods of water purification (e.g., constructed wetlands, floating beds, or intermittent aeration) leads to an increase in the effectiveness and a prolongation of the duration of the EM action. The findings of the study might serve as a guide for the restoration of eutrophic reservoirs by supporting sustainable management of water resources. Nevertheless, further research should be conducted on the effectiveness of EM and their application in the remediation of eutrophic water reservoirs.

Zooplankton as an indicator of the status of contamination of the Mediterranean Sea and temporal trends

Zooplankton has been intensively used as bioindicators of water pollution at global level, however, only few comprehensive studies have been conducted from the Mediterranean Sea and manly dated back to the 1970s. To redress the urgent need for updated data, this study provides information on the presence and levels of contaminants in zooplankton from the Tyrrhenian Sea. Although banned, both PCBs (46.9 ± 37.2 ng g-1) and DDT (8.9 ± 10.7 ng g-1) are still present and widespread, but their contamination appears to be a local problem and to be declining over the past 50 years. Zooplankton accumulates high levels of certain TEs, including Zn (400 ± 388 ppm) and Pb (35.3 ± 45.5 ppm), but shows intermediate concentrations of other TEs, including Cd (1.6 ± 0.9 ppm) and Hg (0.1 ± 0.1 ppm), comparing with both strongly polluted and more pristine marine habitats, which may reflect a general improvement.

Experimental Design and Multiple Response Optimization for the Extraction and Quantitation of Thirty-Four Priority Organic Micropollutants in Tomatoes through the QuEChERS Approach

The chemical contamination in fruit and vegetables represents a challenging analytical issue, with tomatoes deserving to be investigated as they are fundamental components of the Mediterranean diet. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs contamination is of serious concern, due to particulate deposition and to uptake from contaminated soils and water. However, time-consuming, non-simultaneous and/or non-eco-friendly extraction procedures are typically used to investigate organic contamination in tomatoes, with nitro-PAHs that have not yet been studied. Based on these premises, this work reports the development of a QuEChERS-based approach, coupled with gas chromatography/mass spectrometry, for the simultaneous determination of 16 PAHs, 14 PCBs and 4 nitro-PAHs in three tomato cultivars. The effect of dichloromethane, cyclohexane and acetone, as well as of four clean-up phases were studied through the advanced combination of full factorial experimental design and multiple response optimization approaches. The final protocol, based on cyclohexane extraction followed by a double purification step with primary secondary amine and octadecyl silica and a sulfuric acid oxidation, led to 60–120% recoveries (RSD% < 15%). Good repeatability (inter-day precision <15%) and negligible matrix effect (<16%) were confirmed and the protocol was applied to the analysis of real tomato samples purchased in a local market.

Transport, Persistence, and Toxicity of Pollutants in the Sea

Eight research articles and two reviews are included in this Special Issue focused on the transport, persistence, and toxicity of pollutants in different seas: the Western and Central Mediterranean Sea, the Adriatic Sea, the Tyrrhenian Sea, the Baltic Sea, and the South China Sea [...]