In parallel with the growing use of nanoparticle-containing products, their release into the environment over the coming years is expected to increase significantly. With many large population centers located in near-coastal areas, and increasing evidence that various nanoparticles may be toxic to a range of organisms, biota in estuarine and coastal waters may be particularly vulnerable. While size effects may be important in cases, silver nanoparticles have been found to be toxic in large part due to their release of silver ions. However, there is relatively little data available on how nanoparticle coatings can affect silver ion release in estuarine or marine waters. We have found that albumin, as a model for biocorona-forming macromolecules which nanoparticles may encounter in wastewater streams, stabilizes silver colloids from agglomeration in high salinity marine waters by electrosteric repulsion for long time periods. A minimum mass ratio of about 130 for albumin:silver nanoparticles (40 nm) was required for stable dispersion in seawater. Increasing albumin concentration was also found to reduce dissolution of nanoparticles in seawater with up to 3.3 times lower concentrations of silver ions noted. Persistent colloids and slow sustained ion release may have important consequences for biota in these environmental compartments.

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Commercially important bivalve Noah's Ark shell (Arca noae Linnaeus, 1758) represents a high-quality seafood product, but the data on levels of metal contaminants that could pose a human health risk and also on some essential elements that are important for health protection are lacking. This study examineds the concentrations of Cd, Pb, Cr, Ni, Cu, Co, and Zn in the mg/kg wet weight. These levels were lower than the permissible limits for safe consummation of seafood, and only for Cd, some precautions should be taken into account if older shellfish were consumed. Increase of Cd, Cr, and Cu in shell tissue was observed during the tourist season at the site closest to the marine traffic routes, indicating that metal levels in shellfish tissue should be monitored especially carefully monitored during the peak tourist season, to prevent eventual toxic effects due to increased intake of metals, specifically of Cd.

AimTo identify gross deletions in the NF2 gene in a panel of schwannomas from Croatian patients in order to establish their frequencies in Croatian population.MethodsChanges of the NF2 gene were tested by polymerase chain reaction/loss of heterozygosity (LOH) using two microsatellite markers, D22S444 and D22S929.ResultsThe analysis with both markers demonstrated that 43.75% of schwannomas exhibited LOH of the NF2 gene. The D22S444 region exhibited 45.5% of LOHs and the D22S929 region exhibited 14.3% of LOHs. Four LOHs were found in Antoni B, 2 in Antoni A, and 1 in Antoni A and B type tumors.ConclusionThe frequency of changes observed in Croatian patients is broadly similar to that reported in other populations and thus confirms the existing hypothesis regarding the tumorigenesis of schwannomas and contributes to schwannoma genetic profile helping us to better understand its etiology and treatment.

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The distribution of six common metal contaminants (Cd, Cr, Cu, Ni, Pb, Zn) in the bulk (<2 mm) and fine fractions (<63 µm) of freshwater sediments was compared to conclude on the long-existing dilemma which fraction should be used in the investigation of the metal contamination. The environments included in the study (24 rivers, 8 lakes) were very different with respect to sediments origin and composition and they provided a good review of the possible scenarios. For the river sediments, particularly those having >40% of sand fraction, metal concentrations were up to seven times higher in the fine fraction, implying the necessity for considering sand dilution effect in compositional data analysis. The same samples were also characterized with higher organic matter content (OM) in the fine fraction. Lake environments were characterized by fine-grained sedimentation and the difference between metal concentrations in the bulk and fine fraction was not so expressed. The preparation of samples for the geochemical and compositional data mining should be carried out in accordance with the sedimentological characteristics of the investigated environment. It implies that the insight into geological setting and determination of sedimentological characteristics should be an obligatory part of monitoring/investigating metal contamination in freshwater sediments. For river sediments, the analysis of the fine sediment fraction or correction for sediment lithology are advisable.