Knowledge Hub on the Integrated Assessment of Chemical Contaminants and their Effects on the Marine Environment

In a time of environmental awareness, spurred on by the possibility that our world is threatened by climate change, it is important to remember that there are other anthropogenic pressures, which are also essential for addressing the protection of the marine and coastal environment. Pollution is a global, complex issue that contributes to biodiversity loss and poor environmental health and comes from the production and release of many of the synthetic chemicals that we use in our daily lives. Chemical contaminants are often underrepresented as a major contributor of environmental deterioration. The Joint Programming Initiative Healthy and Productive Seas and Oceans (JPI Oceans) established in 2018 the JPI Oceans Knowledge Hub on the integrated assessment of chemical contaminants and their effects on the marine environment. The purpose of the Knowledge Hub was to provide recommendations on how to improve the methodological basis for marine chemical status assessment. The work has resulted in the following policy paper which focuses on improving the efficiency and implementation of integrated assessment methodology of effects of chemicals of emerging concern. Substantial additional knowledge of biological effects is needed to achieve Good Environmental Status (GES) of our oceans and coastal areas. The Knowledge Hub is represented by highly skilled scientists and policy makers, appointed by the JPI Oceans Management Board, to ensure that the recommendations provided are useful for policy making

Report of the Working Group of Biological Effects

The Working Group on Biological Effects of Contaminants (WGBEC) investigates the biological effects of contaminants in the marine environment. The group provides research and increases the understanding of contaminant interactions and effects, including the development of inte-grated biological effects monitoring strategies, which are used to support international research and monitoring. The WGBEC has contributed significantly to the implementation and harmonization of tech-niques that can be used to evaluate the biological effects of pollutants in national monitoring programmes. An overview of national effect-based monitoring programmes of Member States is provided with the aim to support European countries and Regional Seas Conventions on their implementation. A summary of the national effects-based monitoring programmes has been pro-vided by twelve European countries represented at the WGBEC meetings. The adoption of bio-logical effects monitoring can differ widely and comparisons between approaches and the choice of biological effects methods used acts as an important tool. A summary of the main findings is presented. Furthermore, OSPAR's Hazardous Substances and Eutrophication Committee (HASEC) has en-couraged contracting parties to perform targeted biological effects monitoring to enhance the assessment of contaminants in sediment and biota towards the OSPAR QSR2023. WGBEC mem-bers contributed to the integrated biological effects approach assessment by providing data from their national monitoring activities to produce maps and figures to enable interpretations. Revision of the biological effects methods, including new techniques and developments, and the quality assurance of existing methods are core activities for the WGBEC, which require continu-ous discussion and evaluation by the group. Activities include the production of new ICES TIMES documents as well as intercalibration exercises to ensure Member States are providing comparable data for national monitoring. To this end, intercalibration exercises were performed under the BEQUALM programme for two of the more commonly used biological effects meth-ods, including micronucleus formation in mussel haemocytes and PAH metabolites in fish bile. These intercalibrations were successful despite identifying some variation in reported values be-tween laboratories. Further intercalibration exercises are planned and the WGBEC strongly sup-port the need for such quality assurance. In addition to the national monitoring activities and the different methods and approaches for determining the effects of contaminants on biological systems, the WGBEC was interested in discussing some key questions related to the potential impacts of contaminants to marine life. These questions included: the direct and indirect effects of natural and synthetic particles; how climate change and acidification parameters can interact with contaminants and influence bioa-vailability and effect; whether the structure of marine communities can be used to indicate con-taminant exposure; to provide guidance on performing risk assessments for contaminants of emerging concern; and to evaluate the effects of contaminants in marine sediments and whether current sediment toxicity tests are adequate. In addition, and as a wider concept, the linkages between contaminants in the marine environment and human health were also described.S

L'éthoxyrésorufine-o-déethylase, les adduits à l'ADN et les mocronuclei dans les organismes marins. Application à la surveillance des effets biologiques sur les côtes françaises

Three biomarkers [ethoxyresorufm-o-deethylase (EROD), DNA adducts and micronuclei (MN) were studied for biomonitoring applications along French coasts. EROD was developed at an experirnental stage in two pilot sites, Seine Bay and Fos sur Mer, using the dab (Limanda limanda), dragon et (Callionymus lyra), red mullet (Mullus barbatus) and comber (Serranus hepatus) as target species. Higbest EROD activity was observed in the subestuarial part of Seine Bay and at the stations closest to sources of pollution from Cortiou and Fos sur Mer. The suitable number of fish for detection of a significant difference between two EROD activities was deterrnined as a function of sampling variance and a preselected statistical power. A preliminary study on hepatocytes in a primary dragonet culture enabled us to evaluate the toxic cffect of PCB in the marine environment. DNA PAH adducts were measured at the same time as EROD in the liver ofred mullet trawled in the Mediterranean, and PAH was analyzed in sediments. Specific DNA PAH adducts were detected in highly polluted areas. The genotoxic effects of MN were measured in vitro and in vivo in the mussel (Mytilus galloprovincialis) and oyster (Crassostrea gigas). Poor sensitivity was found for oysters along a pollution gradient in the Gironde estuary, but greater sensitivity was obtained when heart cells in primary culture were contaminated with benzo[a)pyrene, cupric sulfate and paper mill effluent. Variations in MN frequency were measured in mussels during four months of monitoring at highly contaminated sites. The major drawback of the MN test for monitoring purposes is that it entails laborious and sometimes subjective microscopie observation.Trois bioindicateurs, L'éthoxyrésorufme-o-déethylase (EROD), les adduits à l'ADN et les micronuclei (MN) ont été étudiés pour une application en biosurveillance des côtes françaises. L'EROD  a été développé à titre expérimental sur les sites pilotes de la baie de Seine et de Fos SN mer-Marseille. Quatre espèces sentinelles, la limande Limanda limanda et le callionyme Callionymus lyra, le rouget barbet de vase Mullus barbatus ainsi que le Serran Serranus hepatus ont été sélectionnées. Les plus fortes activités EROD mesurées dans le foie de poisson, ont été observées dans la zone subestuarienne de la baie de Seine et sur les stations les plus proches des sources de polluants à Cortiou et Fos sur mer. La détermination du nombre de poissons nécessaire pour détecter une différence significative entre deux activités EROD en fonction de la variance d'échantillonnage et pour une puissance donnée ont été réalisé. Une étude préliminaire sur la culture d'hépatocytes de callionyme a permis d'évaluer l'effet toxique des PCB présents dans le milieu marin. Des mesures d'adduits d'HAP à l'ADN ont été réalisés en complémentarité des mesures d'activités EROD de foies de Mullus barbatus pêchés en Méditerranée et de dosages chimiques d'HAP sur le  sédiment. La mesure d'adduits HAP à l'ADN constitue un outil intéressant en surveillance des zones très polluées. La mesure d'effets génotoxiques par les micronuclei a été testée in vitro et in vivo chez la moule et l'huître. Un manque de sensibilité du test MN a été démontré pour des Crassosrrea gigas collectées sur un gradient de pollution en Gironde. Les résultats obtenus par contamination des celIules de coeur en  culture primaire par du Bap, du sulfate de cuivre et un effluent de pâte à papier semblent plus prometeurs. Des variations de la fréquence des MN ont été mesurées chez Mytilus galloprovincialis pendant un suivi de quatre mois sur les sites les plus contaminés. L'obstacle majeur de l'application du test MN en surveillance est une observation microscopique laborieuse et parfois subjective

In vivo effects of metaldehyde on Pacific oyster, Crassostrea gigas: comparing hemocyte parameters in two oyster families.

Pollutants via run-off into the ocean represent a potential threat to marine organisms, especially bivalves such as oysters living in coastal environments. These organisms filter large volumes of seawater and may accumulate contaminants within their tissues. Pesticide contamination in water could have a direct or indirect toxic action on tissues or cells and could induce alteration of immune system. Bivalve immunity is mainly supported by hemocytes and participates directly by phagocytosis to eliminate pathogens. Some studies have shown that pesticides can reduce immune defences and/or modify genomes in vertebrates and invertebrates. Metaldehyde is used to kill slugs, snails and other terrestrial gastropods. Although metaldehyde has been detected in surface waters, its effects on marine bivalves including the Pacific oyster, Crassostrea gigas, have never been studied. Given the mode of action of this molecule and its targets (molluscs), it could be potentially more toxic to oysters than other pesticides (herbicides, fungicides, insecticides, etc.). Effects of metaldehyde on oyster hemocyte parameters were thus monitored through in vivo experiments based on a short-term exposure. In this work, metaldehyde at 0.1 μg/L, which corresponds to an average concentration detected in the environment, modulated hemocyte activities of Pacific oysters after an in vivo short-term contact. Individuals belonging to two families showed different behaviours for some hemocyte activities after contamination by metaldehyde. These results suggested that effects of pollutants on oysters may differ from an individual to another in relation to genetic diversity. Finally, it appears essential to take an interest in the effects of metaldehyde on a wide variety of aquatic invertebrates including those that have a significant economic impact

Pacific oyster (Crassostrea gigas) hemocyte are not affected by a mixture of pesticides in short-term in vitro assays

Pesticides are frequently detected in estuaries among the pollutants found in estuarine and coastal areas and may have major ecological consequences. They could endanger organism growth, reproduction or survival. In the context of high mortality outbreaks affecting Pacific oysters, Crassostrea gigas, in France since 2008, it appears of importance to determine the putative effects of pesticides on oyster susceptibility to infectious agents. Massive mortality outbreaks reported in this species, mainly in spring and summer, may suggest an important role played by the seasonal use of pesticides and freshwater input in estuarine areas where oyster farms are frequently located. To understand the impact of some pesticides detected in French waters, their effects on Pacific oyster hemocytes were studied through short-term in vitro experiments. Bivalve immunity is mainly supported by hemocytes eliminating pathogens by phagocytosis and producing compounds including lysosomal enzymes and antimicrobial molecules. In this study, oyster hemocytes were incubated with a mixture of 14 pesticides and metaldehyde alone, a molecule used to eliminate land mollusks. Hemocyte parameters including dead/alive cells, nonspecific esterase activities, intracytoplasmic calcium, lysosome number and activity and phagocytosis were monitored by flow cytometry. No significant effect of pesticides tested at different concentrations was reported on oyster hemocytes maintained in vitro for short-term periods in the present study. It could be assumed that these oyster cells were resistant to pesticide exposure in tested conditions and developing in vivo assays appears as necessary to better understand the effects of polluants on immune system in mollucks

A novel "Integrated Biomarker Response" calculation based on reference deviation concept

Multi-biomarker approaches are used to assess ecosystem health and identify impacts of environmental stress on organisms. However, exploration of large datasets by environmental managers represents a major challenge for regulatory application of this tool. Several integrative tools were developed to summarize biomarker responses. The aim of the present paper is to update calculation of the "Integrated Biological Response" (IBR) described by Beliaeff and Burgeot (Environ Toxicol Chem 21:1316-1322, 2002) to avoid weaknesses of this integrative tool. In the present paper, a novel index named "Integrated Biological Responses version 2" based on the reference deviation concept is presented. It allows a clear discrimination of sampling sites as for the IBR, but several differences are observed for contaminated sites according to up- and downregulation of biomarker responses. This novel tool could be used to integrate multi-biomarker responses not only in large-scale monitoring but also in upstream/downstream investigations