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Summer outbreaks of the dinoflagellate Alexandrium taylorii Balech are recurrent events in nearshore waters of Sicily (Italy)—a central region in the Mediterranean Sea—producing dense yellowish–green patches. Beyond the local phenomenon, the problem covers a broader geographic scale, involving also other European localities, mostly in Spain. Biological, environmental, and molecular data are reported here from a semi-closed bay of Sicily (Vulcano Island, Tyrrhenian Sea, 2000–2003), showing in summer the recurrence of high-biomass blooms and events of water discolouration. Without underestimating the setbacks to the tourism industry, the ecological impact of A. Taylorii blooms may be important considering the high levels of biomass produced (West Bay, Vulcano: up to a magnitude order of 107 cells l−1, 50–180 μg-Chl a l−1, June 2002 and 2003) and coincident conditions of oxygen supersaturation of the waters (130–170%). Trophic trends in the Tyrrhenian site indicate high amounts of nutrients linked to the increased anthropogenic activity in summer, although recently there has been an apparent shift of the marked eutrophic conditions towards a slighter eutrophy. Genetic data on isolates of A. Taylorii from the Mediterranean Sea are also discussed. Molecular analyses implied the sequencing of target rDNA regions (5. 8S rDNA and ITS regions) of several isolates from different Mediterranean localities, as well as the application of species-specific PCR assays for rapid species identification in preserved field samples. The confirmation of the specific identity provided new insights into the biogeography of this species and further evidence of the occurrence of A. Taylorii in a number of Mediterranean localities, both in the western side (the Catalan coast of Spain) and the eastern area (Greece). Analyses of the molecular diversity of geographically distinct isolates of A. Taylorii from Italy, Spain, and Greece based on the 5. 8S rDNA-ITS region sequences showed a high level of similarity, indicating the existence of an unique Mediterranean population. [ABSTRACT FROM AUTHOR]

The heavy metals transfer from the soil, where they accumulate, to the edible parts of the plants, and then, their entrance in the food chain can represent a source of concern for human health. Among heavy metals, arsenic is one of the most widespread in the soil of Lazio (central region of Italy), where the phytoavailable geogenic arsenic enters the food chain, with a dangerous exposition of the local population. In the first part of this work, plants of radish (Raphanus sativus L.) and lettuce (Lactuca sativa L.) were grown in protected culture in the experimental farm of CREA-AA, where they were daily treated with different concentrations of sodium arsenate dibasic heptahydrate in order to investigate differences in their arsenic accumulation capacities. In order to confirm the results achieved, in the second part of this study, the arsenic concentration was determined in commercial products obtained from contaminated areas of Lazio, and the potential exposition risk for human health through consumption of these widely consumed vegetables was estimated. The highest arsenic concentrations were found in the samples of lettuce. To evaluate the potential health risk from consumption of L. sativa and R. sativus, the estimated daily intake (EDI) for adults, adolescents, and elderly was calculated, finding that HRI (health risk index) index value for arsenic was low (< 1) in the case of chronic consumptions for all samples of radishes, and for the lettuces grown in the area of Viterbo. On the contrary, the lettuces obtained from Tuscania and Tarquinia presented very high concentrations of arsenic and a worrying HRI value. In order to reduce the risk of As toxicity in the people through consumption of the vegetables, the irrigation water should contain less than 0.1 mg As L -1 . For this reason, the authors tested the application of red mud (RM) to remove As from groundwater before using it for the irrigation of radish and lettuce in greenhouse production.