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This study aimed to investigate the relationships between levels of organochlorine compounds (PCBs and DDTs), polycyclic aromatic hydrocarbons (PAHs), metals and biomarkers of exposure (EROD and GST) and oxidative stress biomarkers, in wild and cultured European seabass (Dicentrarchus labrax). Additionally, the fatty acid profile was determined in muscle to assess differences between cultivated and wild specimens of marketable size. Although results pointed to relatively low concentration of contaminants, wild specimens presented enhanced accumulation of metals and cultivated specimens higher levels of organic compounds. Biomarkers were correlated with contaminants in tissues, showing that higher levels can cause effects at the biochemical level. Wild specimens have presented higher content on omega-3 fatty acids in muscle. Besides the useful application of biomarkers in wild species, this study has shown that they can also be applied to monitor biological effects in the fish farming process. [Copyright &y& Elsevier]

Abstract: Endosulfan is a worldwide used insecticide suspected to be highly toxic to aquatic organisms, including fish. Most of the available studies have focused in water exposures, although this pollutant can be transferred through food chain. Therefore, in the present study, the effects of Endosulfan on tilapia (Oreochromis niloticus), when administered through the diet. Fish were fed 21 days with diets containing 1 and 0.5μgg−1 of Endosulfan, after which qualitative histological liver analysis showed that Endosulfan induced hepatocyte destruction, vessel endothelium rupture and increased melanomacrophages aggregates. To test lower environmentally relevant doses of Endosulfan could induce hepatic damage, as well as other negative effects, such as altered phase I metabolism and plasma thyroid hormone levels. Hence, tilapia were orally exposed to 0.1 and 0.001μgg−1 for 35 days. Low environmentally realistic doses of Endosulfan were still able to induce liver histopathological damage such as increased hepatocyte vacuolization and increased eosinophil granular cell aggregates. Liver cytochrome P450 1A activity, evaluated through ethoxyresorufin-o-deethylase (EROD), was enhanced in tilapia exposed to 0.001μgg−1, whereas the highest dose had no measurable effects in this enzyme activity. Fish exposed to 0.1μgg−1 of Endosulfan had depressed T4 plasma levels. Overall, the results of the present study further demonstrate the toxic effects of Endosulfan in tilapia when administered in the diet at environmentally relevant concentrations, which indicates that in the field food chain transfer may also be an importance source of this pollutant. [Copyright &y& Elsevier]

Different risk evaluation approaches have been used to face oil and hazardous and noxious substances (HNS) spills all over the world. To minimize health risks and mitigate economic losses due to a long term ban on the sale of sea products after a spill, it is essential to preemptively set risk evaluation criteria and standard methodologies based on previous experience and appropriate scientifically sound criteria. Standard methodologies are analyzed and proposed in order to improve the definition of criteria for reintegrating previously contaminated marine marketable resources into the commercialization chain in Europe. The criteria used in former spills for the closing of and lifting of bans on fisheries and harvesting are analyzed. European legislation was identified regarding food sampling, food chemical analysis and maximum levels of contaminants allowed in seafood, which ought to be incorporated in the standard methodologies for the evaluation of the decision criteria defined for oil and HNS spills in Europe. A decision flowchart is proposed that opens the current decision criteria to new material that may be incorporated in the decision process. Decision criteria are discussed and compared among countries and incidents. An a priori definition of risk criteria and an elaboration of action plans are proposed to speed up actions that will lead to prompt final decisions. These decisions, based on the best available scientific data and conducing to lift or ban economic activity, will tend to be better understood and respected by citizens. [Copyright &y& Elsevier]

Abstract: The present study evaluated the effects of cyclic variations of hydrostatic pressure (HP) on neurotransmitters in the whole brain of flounder. The concentrations of the biogenic amines L-3,4-dihydroxyphenylalanine (L-DOPA), dopamine (DA), norepinephrine (NE), epinephrine (E), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3-MT), 5-hydroxytryptamine (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) were measured. Fish were subjected to HP cyclic variations which mimic naturally occurring conditions for a period of 14 days. DA, NE and 5-HT concentrations were significantly smaller by 21, 24 and 36%, respectively, compared to control fish. The concentrations of monoamine metabolites HVA, 3-MT and 5-HIAA were also smaller than those in control fish. These results suggest that central monoaminergic systems were influenced during long exposure to cyclic HP. The decreases of central neurotransmitters content might be involved in the physiological and behavioral responses to intermittent HP in fish. [Copyright &y& Elsevier]