Search

In this study, we investigated metal concentrations in Anemonia sulcata specimens from various locations in the Atlantic Ocean and the Mediterranean Sea. A total of 84 individuals were sampled from specific zones, and their tissue samples were processed for metal analysis using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The results revealed notable differences in metal concentrations among the studied regions. The Atlantic Ocean and the Mediterranean Sea were found to have distinct patterns of marine pollution, influenced by a complex interplay of geographical, demographic, industrial, and environmental policy factors. Conversely, the semi-enclosed Mediterranean Sea has a lower natural dilution capacity, leading to the accumulation and prolonged presence of pollutants. Population density and industrial activities in coastal areas play a significant role in pollution disparities between the Mediterranean Sea and the Atlantic Ocean. The Mediterranean coasts, with higher population densities and intensive industrial operations, experience greater strain on marine ecosystems due to increased pollution sources. Additionally, environmental policies and management approaches differ between the two regions, contributing to variations in pollution response and regulation., Competing Interests: Declaration of competing interest All authors declare that the use of animals for this research complies with the requirements of European legislation on the use of animals for experimentation. All samples were collected by researchers in the Canary Islands. Therefore, we faithfully comply with the Code of Practice for Housing and Care of Animals Used in Scientific Procedures., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

One hundred and ninety-two samples from six species of mollusks classified into the following taxonomic classes: Gastropoda (Patella aspera, Patella candei crenata), Bivalvia (Mytilus galloprovincialis, Ensis directus), and Cephalopoda (Abraliposis morisii, Pyroteuthis margatifera) were investigated. Samples were collected in the Atlantic Ocean (Canary Islands and Galicia). The concentrations of Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, V, and Zn were determined by ICP-OES. Statistical analysis verified that the classes of benthic organisms had the highest concentration of elements. However, the Cephalopoda class had the highest Cd (1.685 ± 0.929 mg/kg) and Pb (0.826 ± 1.104 mg/kg) content. On the other hand, the values obtained in this study were compared with studies conducted in other parts of the world to verify the environmental state of the Atlantic Ocean using the organisms studied as bioindicators.

Decompression sickness (DCS) was first diagnosed in marine turtles in 2014. After capture in net fisheries, animals typically start showing clinical evidence of DCS hours after being hauled on-board, often dying if untreated. These turtles are normally immediately released without any understanding of subsequent clinical problems or outcome. The objectives of this study were to describe early occurrence and severity of gaseous embolism (GE) and DCS in marine turtles after incidental capture in trawl gear, and to provide estimates of on-board and post-release mortality. Twenty-eight marine turtles were examined on-board fishing vessels. All 20 turtles assessed by ultrasound and/or post-mortem examination developed GE, independent of season, depth and duration of trawl and ascent speed. Gas emboli were obvious by ultrasound within 15 minutes after surfacing and worsened over the course of 2 hours. Blood data were consistent with extreme lactic acidosis, reduced glomerular filtration, and stress. Twelve of 28 (43%) animals died on-board, and 3 of 15 (20%) active turtles released with satellite tags died within 6 days. This is the first empirically-based estimate of on-board and post-release mortality of bycaught marine turtles that has until now been unaccounted for in trawl fisheries not equipped with turtle excluder devices.

The precise number of Okenia taxa inhabiting the Mediterranean Sea, as well as their general taxonomy, varies according to different specialists. So far, eight valid species have been reported from the area: Okenia aspersa (Alder & Hancock, 1845), Okenia cupella (Vogel & Schultz, 1970), Okenia elegans (Leuckart, 1828), Okenia hispanica Valdés & Ortea, 1995, Okenia impexa Er. Marcus, 1957, Okenia leachii (Alder & Hancock, 1854), Okenia mediterranea (Ihering, 1886), and Okenia zoobotryon (Smallwood, 1910). Of these, only three (O. elegans, O. hispanica, and O. mediterranea) have their type localities in the Mediterranean Sea, whereas the others were described from different biogeographic areas and later included in the Mediterranean biota. We carried out a review on Mediterranean Okenia species through an integrative approach, based on a wide literature search and a morphological and molecular analysis of available type material and samples collected recently. The present study confirmed the presence of O. aspersa, O. elegans, O. hispanica, and O. mediterranea in the Mediterranean Sea, although leaving remaining questions about some of those taxa. The distribution of O. cupella, O. impexa, and O. zoobotryon is limited to the western Atlantic, and of O. leachii to the eastern Atlantic. All specimens previously identified as O. cupella, O. impexa, and O. zoobotryon by different authors in the Mediterranean Sea were repeatedly misidentified. Thus, we describe Okenia problematica sp. nov. and Okenia longiductis sp. nov., from the "Mediterranean" Okenia cupella/impexa and O. zoobotryon. We also consider here Okenia pusilla Sordi, 1974 a nomen dubium and include a redescription of the holotype of O. cupella. A molecular phylogeny, including all the sequenced Okenia species, was performed in order to evaluate the evolutionary relationships of the newly described species with the other congeneric taxa., Competing Interests: The authors have declared that no competing interest exist.

Seaweeds are being consumed more often worldwide and are a source of essential minerals, fiber, vitamins, amino acids, and various bioactive compounds that have many beneficial effects on human health. However, marine pollution and the high capacity of seaweed to absorb metals may mean this food can also be dangerous to human health. The concentrations of some trace elements (B, Ba, Fe, Ni, Li, and V) and toxic metals (Al, Cd, and Pb) were determined in various species of wild seaweeds in the Phaeophyta group of brown algae from the Atlantic Ocean. Inductively coupled plasma atomic emission spectrometry revealed high concentrations of Al (256 mg/kg dry weight), Pb (3.92 mg/kg dry weight), and Cd (0.20 mg/kg dry weight) in Padina pavonica. Pb contributed the most to the tolerable daily intake (TDI) of toxic metals in these samples; 57.2 and 45.3% of the TDI for Pb was found in 5 g of dehydrated P. pavonica and Halopteris scoparia, respectively. This percent contribution is half of the recommended TDI for this metal, which is 34.24 μg/day; therefore, high consumption of these species is discouraged. The maximum TDIs established by various institutions for the other metals were not exceeded from the daily consumption of 5 g of the other dehydrated seaweeds evaluated in this study.