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The MONITOOL project (2017-2023) was carried out to describe the relationships between total dissolved and labile metal concentrations measured in spot water samples and in concurrently deployed Diffusive Gradients in Thin -films (DGTs) passive samplers, respectively. The ultimate aim was to adapt existing marine metal Environmental Quality Standards (EQS marine water ) for DGTs, enabling their use in the context of the European Directives (the Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD)). Time -integrated metal concentrations provided by DGTs, representing several days, are an advantage compared to conventional spot sampling, especially in highly dynamic systems, such as transitional waters. Hence, the MONITOOL project aimed to provide a robust database of dissolved and labile metal concentrations in transitional and coastal waters, based upon co -deployments of DGTs and collection of spot water samples at several sampling sites (England, France, Ireland, Italy, Northern Ireland, Portugal, Scotland and Spain), followed subsequently by DGT and water metal analysis. Samplings were carried out in 2018 and 2022, following agreed protocols developed in the framework of the project. The MONITOOL dataset includes metal concentrations from DGTs, measured with Inductively Coupled Plasma Mass Spectrometry (ICP-MS: Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) and in concurrently collected spot water samples by ICP-MS (Al, Cd, Co, Cu, Mn, Ni, Pb, Zn) and Anodic/Cathodic Stripping Voltammetry (ASV/CSV: Cd, Pb, Ni). Moreover, data on seawater physical -chemical parameters (salinity, temperature, dissolved oxygen, pH, turbidity, total suspended solids, dissolved organic carbon, and total organic carbon) is provided. This database presents the results obtained using, concurrently, different forms of sampling and analytical techniques, enabling the comparison of the results obtained by these strategies and allowing the adaptation of EQS in marine water (EQ

The quality of oyster spermatozoa has become an issue for modern aquaculture. However, reliable protocols used to assess gamete quality are lacking. The aim of this work is to define a standardised experimental fertilisation protocol for Pacific oyster oocytes. Six experiments have been carried out in this study. The optimal conditions for Pacific oyster experimental fertilisation have been defined: (1) oocytes can be conserved in seawater for at least 4 h before fertilisation. (2) oocyte concentration: 100-1000 ml(-1) seawater, (3) fertilisation volume: 10-100 nil, (4) spermatozoa: oocyte ratio: 400 to maintain discriminating conditions, (5) gamete contact time: longer than 10 mill and (6) fertilisation and incubation temperatures: both 19 degrees C. The effect of individual male significantly influenced the fertilisation success. The results of this study will be exploited for spermatozoal quality analysis in combination with other techniques. (C) 2008 Elsevier B.V. All rights reserved.

Standardized experimental protocols designed to study Pacific oyster (Crassostrea gigas) gamete quality have not been previously published. Gamete sampling variations and confounding effect of interacting factors result in large variations between replicates, decreasing the effects of the studied factors. This work aims at defining a standardized procedure for incubation of oyster embryos designed for experimental purposes. In a first phase, four experiments were developed to improve embryo sampling and handling. They showed that a minimum of 50 embryos must be counted to decrease the variation between counting replicates. For reliable results, sampling must be carried out from 0 to 7 min after a careful agitation of seawater containing embryos (salinity: 35.6 parts per thousand). Compared to control and a 30 cm one, the D-larval yield of embryos submitted to a 1 m fall was significantly reduced, showing the limited effect of mechanical disturbance on Pacific oyster oocytes survival. Then, maintaining 2.2 million embryos in 250 ml seawater for a two hours period resulted in a decrease of D-larval yield which could not be explained by a decrease of O-2 content and pH of seawater. The second phase of this work included a set of five experiments, defining experimental incubation conditions. A higher larval yield was observed using 1.8 1 beakers and 150 1 tanks compared to 0.3 ml microtiter plates and 1 1 fish egg incubators. Higher larval yields were recorded when embryo density ranged from 5 to 100 ml(-1), compared to values between 500 and 2000 ml(-1). Compared to controls (no antibiotic or no presence of light), no changes of D-larval yield were observed by adding 20 ppm chloramphenicol or by maintaining embryos in total darkness. Then, a significant decrease of pH and O-2 content was observed during the incubation period. However, these changes could not be considered as limiting for Pacific oyster embryo development. In conclusion, experimental incubation conditio