Levels of trace elements in the blood of chick gulls from the English Channel: Spatial and trophic implications.

Anthropogenic activity has disturbed the natural distribution and circulation of trace elements in the environment. This has led to increased background levels of numerous elements, causing global pollution. In this context, seabirds are relevant bioindicators of environmental contamination.

Mercury Accumulation and Transfer in Hydrothermal Coastal Environment: The Case of the Geothermal Plant of Bouillante.

Geothermal vents can constitute local significant sources of mercury (Hg) in the environment. The geothermal power plant of Bouillante (Guadeloupe, Lesser Antilles) artificially enhances the release of hydrothermal water in shallow areas of the bay. To assess the impact of this release on the Hg transfer in the environment, Hg concentrations were assessed in sediments, sulphur-oxidising bacteria and six animal species (urchin, sponges and fish) with various diets and trophic levels from the Bouillante Bay and a distant Control Site.

Assessing the impacts of trace element contamination on the physiology and health of seabirds breeding along the western and southern coasts of Portugal.

Coastal seabirds serve as sentinels of ecosystem health due to their vulnerability to contamination from human activities. However, our understanding on how contaminant burdens affect the physiological and health condition of seabirds is still scarce, raising the uncertainty on the species' vulnerability vs tolerance to environmental contamination. Here, we quantified 15 Trace Elements (TE) in the blood of gull (yellow-legged gull Larus michahellis and Audouin's gull Ichthyaetus audouinii) and shearwater (Cory's shearwater Calonectris borealis) adults, breeding in five colonies along the Portuguese coastline.

Spatial distribution of selenium-mercury in Arctic seabirds.

Mercury (Hg) is a metallic trace element toxic for humans and wildlife that can originate from natural and anthropic sources. Hg spatial gradients have been found in seabirds from the Arctic and other oceans, suggesting contrasting toxicity risks across regions. Selenium (Se) plays a protective role against Hg toxicity, but its spatial distribution has been much less investigated than that of Hg.

Preliminary inter-port study of the quality of environments using physiological responses of invertebrates exposed to chronic trace element and organic contamination in Corsica (Mediterranean Sea).

Port areas are socio-ecosystems impacted by chronic mixture pollution. Some marine species benefit from living there and may be studied to define the ecological state of such environments. In this study, the risks of chronic chemical contamination and its consequences on three marine molluscs were evaluated in North Corsica (France) port areas.

Active and passive biomonitoring of trace elements, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls in small Mediterranean harbours.

Pollution particularly affects coastal ecosystems due to their proximity to anthropic sources. Among those environments, harbours are subjected to marine traffic but also to accidental and chronic pollution. These areas are thus exposed to complex mixtures of contaminants such as trace elements and organic contaminants which can impact marine species, habitats, and ecosystem services.

Trace elements and δN values in micronekton of the south-western Indian Ocean.

Trace elements and δN values were analysed in micronekton (crustaceans, fishes and squids) sampled in the south-western Indian Ocean. Myctophids were associated with high concentrations of arsenic at La Pérouse and MAD-Ridge seamounts, and with lead and manganese at MAD-Ridge and in the Mozambique Channel. The difference in cadmium, copper and zinc concentrations between micronekton broad categories reflected differing metabolic and storage processes.

The role of tropical small-scale fisheries in trace element delivery for a Small Island Developing State community, the Seychelles.

The concentrations of 13 trace elements were determined in 1032 muscles of 54 small-scale fisheries species collected from the Seychelles waters between 2013 and 2019. Overall, profiles were dominated by zinc (Zn) > arsenic (As) > iron (Fe) > copper (Cu) > selenium (Se), with the spiny lobsters, spanner crab and octopus exhibiting the highest levels of As, Cu and Zn while fish had higher Fe concentrations. Both taxonomy-dependent processes and ecological factors explained the interspecific differences of trace element profiles observed.

Relationships between stable isotopes and trace element concentrations in the crocodilian community of French Guiana.

Trace elements in the blood of crocodilians and the factors that influence their concentrations are overall poorly documented. However, determination of influencing factors is crucial to assess the relevance of caimans as bioindicators of environmental contamination, and potential toxicological impact of trace elements on these reptiles. In the present study, we determined the concentrations of 14 trace elements (Ag, As, Cd, Cr, Co, Cu, Fe, Hg, Pb, Mn, Ni, Se, V, and Zn) in the blood of four French Guiana caiman species (the Spectacled Caiman Caiman crocodilus [n = 34], the Black Caiman Melanosuchus niger [n = 25], the Dwarf Caiman Paleosuchus palpebrosus [n = 5] and the Smooth-fronted Caiman Paleosuchus trigonatus [n = 20]) from 8 different sites, and further investigated the influence of individual body size and stable isotopes as proxies of foraging habitat and trophic position on trace element concentrations.

High inter-species variability in elemental composition of the twilight zone fauna varies implications for predators and exploitation by humans.

While the importance of oceanic micronektonic species in biogeochemical cycles and in the transfer of matter in food webs is globally recognized, specific knowledge on elemental concentrations and their variability within this community is still poorly documented. Here, we report for the first time in the Bay of Biscay, North-East Atlantic, the body composition in various biological parameters and chemical elements of a meso-to bathypelagic micronektonic community. Stable carbon and nitrogen isotope compositions (δC, δN), C:N ratios, energy density, as well as the concentrations in 6 macro-minerals and 13 trace elements including essential (micro-nutrients) and non-essential elements (undesirables, with no know biological function) were measured in whole organisms of 4 crustacean and 11 fish species caught simultaneously around 800 m depth.

Risk and benefit assessment of seafood consumption harvested from the Pertuis Charentais region of France.

Seafood is well recognized as a major source of Long Chain n-3 Polyunsaturated Fatty Acids (LC n-3 PUFA, especially ecosapentaenoic acid, i.e. EPA and docosaheaxaenoic acid, i.

Lead, mercury, and selenium alter physiological functions in wild caimans (Caiman crocodilus).

Environmental contaminants affect ecosystems worldwide and have deleterious effects on biota. Non-essential mercury (Hg) and lead (Pb) concentrations are well documented in some taxa and are described to cause multiple detrimental effects on human and wildlife. Additionally, essential selenium (Se) is known to be toxic at high concentrations but, at lower concentrations, Se can protect organisms against Hg toxicity.

Mercury in the tissues of five cephalopods species: First data on the nervous system.

Mercury (Hg), one of the elements most toxic to biota, accumulates within organisms throughout their lifespan and biomagnifies along trophic chain. Due to their key role in marine systems, cephalopods constitute a major vector of Hg in predators. Further, they grow rapidly and display complex behaviours, which can be altered by neurotoxic Hg.

Is metallothionein in Mimachlamys varia a suitable biomarker of trace elements in the waters of the French Atlantic coast?

The development of human activities along the Atlantic coast is responsible for the chronic pollution of the environment with organic and inorganic contaminants. In recent years, environmental regulations such as the MSFD (2008/56/EC) and the OSPAR commission have been developed to preserve coastal environments, giving rise to studies in aquatic biomonitoring. One of them is to use biomarkers to observe the pollutants impact on coastal species such as the bivalve Mimachlamys varia.

High density polyethylene (HDPE) microplastics impair development and swimming activity of Pacific oyster D-larvae, Crassostrea gigas, depending on particle size.

Understanding the effects of plastic debris on marine ecosystems is essential in encouraging decision-makers to take action. The present study investigates the effect of a 24 h experimental exposure to high density polyethylene (HDPE) microplastics (MPs) of different sizes (4-6, 11-13 and 20-25 μm) and at three concentrations (0.1, 1 and 10 mg MP.

Biomonitoring of Mimachlamys varia transplanted to areas impacted by human activities (La Rochelle Marina, France).

The development of human activities on French Atlantic coastlines (La Rochelle) lead to chronic pollution of the environment by organic (pesticides, hydrocarbons, agrochemicals) and inorganic (heavy metals) contaminants. These past years, several regulations have been implemented to preserve coastal environments. The purpose of this study was to perform biomonitoring of bivalve species using an outdoor caging technique.

Trace Element Concentrations in European Pond Turtles (Emys orbicularis) from Brenne Natural Park, France.

We assessed trace elements concentration in European pond turtle (Emys orbicularis) from Brenne Natural Park (France). We sampled road-killed turtles (N = 46) to measure the concentrations of 4 non-essential (Ag, Cd, Hg, and Pb) and 10 essential (As, Co, Cr, Cu, Fe, Mn, Ni, Se, V, and Zn) elements in muscle, skin, liver and claws. Body size or sex did not influence the concentrations of most elements; except for Hg (liver, skin and claws) and Zn (muscle) which increased with body size.

Assessment of the biological quality of port areas: A case study on the three harbours of La Rochelle: The marina, the fishing harbour and the seaport.

This work was designed to investigate biological impacts at 3 dates (day 0, day 7 and day 21) on black scallops (Mimachlamys varia) in the three ports areas of La Rochelle town in winter 2017. In order to assess the biological effects on the wild population of black scallops, bivalves were place in four different locations: in the three ports (semi-closed areas), and in a marshland uncontaminated site (closed area). Biomarkers of effects (heavy metals) and exposure (oxidative stress and immunological effects) were assessed in the digestive glands of specimens in order to compare two techniques of sampling: "pool" technique and "inter-subject" technique.

What is the relationship between the bioaccumulation of chemical contaminants in the variegated scallop Mimachlamys varia and its health status? A study carried out on the French Atlantic coast using the Path ComDim model.

Increasing activity along the French Atlantic coast has led to chronic pollution with, in particular, mixtures of contaminants such as hydrocarbons, phytosanitary products, PCBs and heavy metals. Based on previous research, pollution biomarkers were used in this study as they can indicate health status when monitoring the impact of pollutants on coastal species such as the marine bivalve Mimachlamys varia. Mollusc bivalves were sampled in March 2016, in open and semi-open areas (a harbour zone), from thirteen sites which differed in terms of their level of pollution, and were located along the Atlantic coast from Brittany down to the Nouvelle-Aquitaine region.

Tracking trace elements into complex coral reef trophic networks.

The integration, accumulation and transfer of trace elements across the main tropic levels of many food webs are poorly documented. This is notably the case for the complex trophic webs of coral reef ecosystems. Our results show that in the south-west lagoon of New Caledonia both abiotic (i.

From Antarctica to the subtropics: Contrasted geographical concentrations of selenium, mercury, and persistent organic pollutants in skua chicks (Catharacta spp.).

Seabirds integrate bioaccumulative contaminants via food intake and have revealed geographical trends of contamination in a variety of ecosystems. Pre-fledging seabird chicks are particularly interesting as bioindicators of chemical contamination, because concentrations in their tissues reflect primarily dietary sources from the local environment. Here we measured 14 trace elements and 18 persistent organic pollutants (POPs) in blood of chicks of skuas that breed in four sites encompassing a large latitudinal range within the southern Indian Ocean, from Antarctica (Adélie Land, south polar skua Catharacta maccormicki), through subantarctic areas (Crozet and Kerguelen Islands, brown skua C.

Trophic ecology drives contaminant concentrations within a tropical seabird community.

To support environmental management programs, there is an urgent need to know about the presence and understand the dynamics of major contaminants in seabird communities of key marine ecosystems. In this study, we investigated the concentrations and trophodynamics of trace elements in six seabird species and persistent organic pollutants (POPs) in three seabird species breeding on Grand Connétable Island (French Guiana), an area where the increase in human population and mining activities has raised concerns in recent years. Red blood cell Hg concentrations in adults were the highest in Magnificent frigatebirds Fregata magnificens (median: 5.

First data on three bivalve species exposed to an intra-harbour polymetallic contamination (La Rochelle, France).

Evaluating diffuse sediment contamination in the environment is a major concern with the aim of reaching a good chemical and ecological state of the littoral zone. In this study the risks of chronic chemical contamination and consequences in the bivalves Crassostrea gigas, Mytilus sp. and Mimachlamys varia were evaluated in coastal environments.

Trace elements in oceanic pelagic communities in the western Indian Ocean.

The mineral composition of target and non-target pelagic fish caught by purse-seiners and longliners in the western-central Indian Ocean was determined. From the 10 essential elements analysed, selenium and zinc showed the highest concentrations in swordfish and blue marlin while Indian mackerel appeared as a good source of copper, iron and chrome. All catch had levels of lead and cadmium, two toxic elements, below the maximum sanitary limits.