Contamination levels and state assessment in the lakes of the Oliveri-Tindari Lagoon (North-Eastern Sicily,Italy)

The Oliveri-Tindari Lagoon, located in North-Eastern Sicily (Italy) and composed of six lakes, is subject to continuous environmental changes. An integrated study focusing on sediment features and levels of contamination was carried out for three of the six lakes, which are of ancient origin: Verde, Mergolo della Tonnara and Marinello. A high primary production (26.89 μg l^?1) was detected at Lake Verde; texture classification showed a typical grain size in the sediments of all lakes; the study of macronutrients highlighted 17.08 of total carbon in sediments from Lake Mergolo della Tonnara; toxic elements were detected at higher concentrations in the sediments of Lake Marinello in comparison to the others, while arsenic was found in high concentrations in all the samples tested, especially in Lake Verde, with a mean value of 17.25 mg kg^?1 dry weight (d.w.). All the organic contaminants, except 4, 4′-dichlorodiphenyldichloroethylene, were below the detection limits in the sediments. Minimal microbiological contamination was found in both water and sediment samples. In the latter, we isolated several bacterial strains thriving in the presence of arsenic, which play a role in the biogeochemical cycle of arsenic. These preliminary results, obtained for the first time using a multidisciplinary approach, provide general information about the Oliveri-Tindari Lagoon area.     

Chemo-ecological studies on hexactinellid sponges from the Southern Ocean

Hexactinellids (glass sponges) are an understudied class with syncytial organization and poor procariotic associations, thought to lack defensive secondary metabolites. Poriferans, though, are outstanding sources of bioactive compounds; nonetheless, a growing suspicion suggests that many of these chemicals could be symbiont-derived. In Polar latitudes, sponges are readily invaded by diatoms, which could provide natural products. Hexactinellids are typical of deep waters; but in Antarctica, they dominate the upper shelf providing shelter and food supply to many opportunistic mesograzers and macroinvertebrates, which exert strong ecological pressures on them. Aiming to examine the incidence of defensive activities of hexactinellids against consumption, feeding experiments were conducted using their lipophilic fractions. Antarctic hexactinellid and demosponge extracts were tested against the asteroid Odontaster validus and the amphipod Cheirimedon femoratus as putative sympatric, omnivorous consumers. Hexactinellids yielded greater unpalatable activities towards the amphipod, while no apparent allocation of lipophilic defenses was noted. After chemical analyses on the lipophilic fractions from these Antarctic glass sponges, quite similar profiles were revealed, and no peculiar secondary metabolites, comparable to those characterizing other poriferans, were found. Instead, the lipidic compounds 5α(H)-cholestan-3-one and two glycoceramides were isolated for their particular outspread presence in our samples. The isolated compounds were further assessed in asteroid feeding assays, and their occurrence was evaluated for chemotaxonomical purposes in all the Antarctic samples as well as in glass sponges from other latitudes by NMR and MS. Characteristic sphingolipids are proposed as chemical markers in Hexactinellida, with possible contributions to the classification of this unsettled class.     

Hospital admissions in Iran for cardiovascular and respiratory diseases attributed to the Middle Eastern Dust storms

Environmental Science and Pollution Research - The main objective of this study was to assess the possible effects of airborne particulate matter less than 10 μm in diameter (PM10)...     

Lysosomal,genetic and chromosomal damage in haemocytes of the freshwater bivalve (Unio pictorum) exposed to polluted sediments from the River Cecina (Italy)

The response to chemical disturbance of an Italian river (Cecina River) characterised by high levels of trace metals was assessed in the sentinel species freshwater painter’s mussel (Unio pictorum). We exposed U. pictorum in the laboratory to metal, metalloid and other trace element polluted river sediments in order to evaluate genetic and cellular biomarkers. Bivalves exposed to sediments taken from all the impacted sites of the river basin exhibited a significant impairment at the DNA, chromosomal and lysosomal levels. The lysosomal membrane stability of circulating haemocytes, assessed by the Neutral Red Retention Time, was found to be higher in specimens from Lake Maggiore and Berignone, while exhibited a significant decrease in specimens exposed to Ponteginori sediments. An increase of DNA migration in specimens exposed to the two contaminated sites in comparison with controls was found. Moreover, higher micronucleated haemocytes frequencies were observed in bivalves exposed to sediments collected at Possera 1 site. This study suggested that biomarkers evaluating cellular impairment, genetic and chromosomal damages, are highly sensitive and suitably applied to laboratory experiments. The painter’s mussel was confirmed to be an appropriate sentinel species for quality assessment in metal-contaminated freshwater environments.     

Multilevel approach to organizational and group safety climate and safety performance: Co-workers as the missing link

The aim of this study is to test a model on the relationships between organizational and group safety climate and safety performance, that highlights the importance of co-workers as a safety climate agent side by side supervisors at group level. The idea is to consider the co-workers’ safety climate as a necessary part of a multilevel model of safety climates’ framework associated to safety performance. Firstly, the assessment of the safety climates’ framework which consider organizational safety climate and at group level supervisor’s and co-workers’ safety climate was performed. Then, the mediating role of co-workers’ safety climate between organizational and supervisor’s safety climate, and worker’s safety behaviours was explored. From the literature, the importance to study safety climate in a multilevel perspective by a theoretical and methodological point of view is known. For these reasons the proposed models were tested with multilevel structural equation modelling. We used a two-level design which considered the individual level and the work-group level. Data collection involved 991 blue-collars, belonging to 91 work groups, from five Italian manufacturing companies. The research highlighted the importance of considering at group level not only climate referred to supervisor, but also climate referred to co-workers. Furthermore, results confirmed the mediating role of co-workers’ safety climate and revealed that co-workers’ safety climate had a stronger influence on safety behaviours, and in particular on safety participation, than supervisor’s safety climate, at individual level as well at group level.     

Population structure of Brachidontes pharaonis (P. Fisher, 1870) (Bivalvia, Mytilidae) in the Mediterranean Sea, and evolution of a novel mtDNA polymorphism

Brachidontes pharaonis (Fisher P, 1870) is an Indo-Pacific mussel that has colonized the Mediterranean Sea via the Suez Canal. Mussels may have migrated by natural dispersal of pelagic larvae, or they may have been transported on the hulls of ships, or in ballast water, or by some combination of these. Mitochondrial COI sequences (618 bp) from 101 mussels from six localities in the central and eastern Mediterranean Sea and from one site in the Red Sea were used to describe population structure. Analysis of molecular variance indicated that frequencies differed among populations, and that 92% of the variation resided within populations. The majority of haplotypes were private alleles. No simple pattern of longitudinal variation was detected for haplotype frequencies, haplotype diversity, or nucleotide diversity. A variety of tree-building algorithms (NJ, MP, ME) gave consistent results, showing two sister groups. One clade had a leucine (L-form) and the other one a methionine (M-form) at the 30th amino acid. These sympatric forms were detected within all localities and they had similar frequencies in males and females. The M- and L-form were separated by a 7.3% sequence divergence, indicating that this is an ancient polymorphism. Closely related species of mussels had exclusively the L-form, so we infer that the M-form evolved from the L-form lineage of B. pharaonis, probably in the northern portion of the Red Sea. Neutrality tests detected an excess of rare mutations, a pattern of variation expected in expanding populations. Patterns of variation detected by Tajima’s D suggest that some form of balancing selection has maintained this polymorphism.