Search

The subcellular effects of pollution were evaluated using two lysosomal biomarkers in mussels, Mytilus galloprovincialis , deployed periodically over a period of 5 years in a harbour area in the Bay of Muggia (Gulf of Trieste, North Adriatic Sea) that is strongly influenced by anthropogenic activities. Mussels were collected from a clean marine farm and analysed (sample T0). A sub-sample was transplanted to the harbour site (sample M) and analysed after about 12 weeks. An additional sub-sample was relocated within the farm as a control and was also tested at the end of the 12-week period (sample T1). The transplantation procedures were repeated twice yearly for 5 consecutive years, starting in 2009. Two well-established lysosomal biomarkers, i.e. lysosomal membrane stability and lipofuscin accumulation, were evaluated in hepatopancreas cells. The body condition index and mortality rate were also assessed. Moreover, various pollutants were determined in both mussel flesh, for a better comprehension of the biological response, and sediments, for a general characterization of the study area. As a whole, the applied biomarkers were found to be appropriate for determining the responses of mussels to environmental pollutant loads over time. Variations in lysosomal membrane stability and lipofuscin content were mostly related to total PAHs and metals respectively. Our results confirm the usefulness of active biomonitoring in evaluating pollution trends in marine coastal areas and in particular the value of lysosomal biomarkers as a rapid screening tool for highlighting pollutant effects at least at organism level. [ABSTRACT FROM AUTHOR]

Detecting the anthropogenic impacts of offshore gas platforms requires reliable tools, because the traditional evaluation based only on chemical analyses is neither appropriate nor sufficiently sensitive. Thus, a 3-year monitoring project was carried out to evaluate the impact of a platform based on a chemical–biological approach. Benthic communities are investigated as they are widely used to monitor the effects of marine impacts because the organisms are mostly sessile and integrate the effects of pollutants over time. Changes in benthic infauna, sediments and water quality, as well as biota bioaccumulation, caused by drilling and platform operations were evaluated experimentally. Furthermore, mussels (Mytilus galloprovincialis) were collected seasonally from the platform legs, both close to and far from the sacrificial anodes and at a control site. Responses of biomarkers of exposure and effect were related to the average levels of polycyclic and aliphatic hydrocarbons, organic matter content and heavy metals in bivalve tissues. Our data suggested that a slight perturbation can be detected only by integrating the results of chemical analyses on water and sediments and those obtained from benthic biological surveys. [ABSTRACT FROM PUBLISHER]

Abstract: Despite a large number of gas platforms existing in the Adriatic Sea, which is a semi-enclosed basin characterized by a slow turnover rate and increasing industrial as well as other anthropogenic activities, the effects of these structures on the aquatic ecosystem require further investigation. Since 1998, multidisciplinary studies have been performed by CNR-ISMAR to comply with legislation and to support the development of protocols for the monitoring of offshore activities in the Adriatic Sea. The present study was developed to implement a biomonitoring plan to assess the ecotoxicological effects of the extraction activities of an off-shore gas platform. Biomarkers were evaluated in mussels collected from the platform in relation to physiological stress, DNA damage, cellular damage, oxidative stress and exposure effects. Organic contaminants and trace element bioaccumulation were also assessed in the soft body of the mussels to correlate bioaccumulation of pollutants with biomarker responses. The results indicate an absence of platform-related environmental stress. [Copyright &y& Elsevier]

This study is focused on evaluating biological effects on the target species Chamelea gallina as a result of repeated exploitation of clam beds by hydraulic dredging. A biomarker approach was adopted and two physiological indices were applied: adenylate energy charge (AEC) (biochemical level) and reburrowing behaviour (organism level). The aim was to investigate the biological response to various types of fishing, i.e., commercial systems using water at high pressures (HP), and experimental systems at lower pressures (LP) in the field, and to evaluate the response of clams to mechanical stress in the laboratory. Field results showed that HP-treated clams exhibited significantly lower levels of AEC compared with LP treatments. A similar trend was shown by reburrowing behaviour; HP-treated clams reburrowed less. Laboratory results were less clear: a very low level of AEC was measured in both control and treated clams. These poor conditions in foot muscle did not indicate worsening at organism level, as no dead or dying clams were recorded throughout the experiment. However, repeated mechanical stress reduced the percentage of reburrowing clams, which suggested that harvesting may affect reburrowing behaviour. [Copyright &y& Elsevier]