Fungal spores and pollen in particulate matter collected during agricultural activities in the Po Valley (Italy)

Airborne particulate matter (PM) containing fungal spores and pollen grains was sampled within a monitoring campaign of wheat threshing, plowing and sowing agricultural operations. Fungal spores and pollen grains were detected and identified on morphological basis. No studies were previously available about fungal spore and pollen content in agricultural PM in the Po Valley. Sampling was conducted in a Po Valley farmland in Mezzano (Ferrara, Italy). The organic particles collected were examined by scanning electron microscopy with energy dispersive X-ray spectrometer. Fungal spores and pollen grains were identified when possible at the level of species. The most frequent components of the organic particles sampled were spores of Aspergillus sp., which could represent a risk of developing allergies and aspergillosis for crop farmers.     

Immediate biomarker responses to benzo[a]pyrene in polluted and unpolluted populations of the blue mussel (Mytilus edulis L.) at high-latitudes

Immediate biomarker responses of two high-latitude populations of the blue mussel Mytilus edulis to benzo[a]pyrene (B[a]P) were evaluated. Mussels collected from a clean and a polluted site in southwest Iceland were exposed to the nominal dose of 100 microg B[a]P L(-l) for 3 h, after 4 days of acclimatization in clean seawater. To test the sensitivity to the toxicant and immediate biological responses, the following biomarkers were used: DNA single strand breaks, heart rate and feeding rate. All the biomarkers revealed differences between the study sites. Irrespective of the origin of the organisms, the short time exposure to the high B[a]P concentration did not induce DNA single strand breaks or significantly affect the feeding rate. However, the heart rate results showed significantly different responses. The mussels from the polluted site (Reykjavík harbour) increased their heart rate when exposed to B[a]P, while no difference was observed between the heart rate values of the individuals from the clean site (Hvassahraun). The mussels seem to sense the pollutant they have been previously exposed to, and their acute response indicates physiological adaptation to the polluted environment. The results indicate limited sensitivity and temporal predictivity, i.e. transient measurable changes of these biomarkers, as well as showing that the background of the organisms should be considered when evaluating short-term biomarker responses to contaminants.     

The influence of seawater temperature on zooid size and growth rate in Pentapora fascialis (Bryozoa: Cheilostomata)

Zooid size variation and growth banding in the bryozoan Pentapora fascialis, collected from the South of Great Britain to the South of Italy, were investigated in order to test their relationship with the variation of seawater temperature. Zooid length appeared to be more sensitive than zooid area and width to temperature variation. The longest zooids were budded in localities that typically experience low seasonal variation in temperature (3.2–7.5°C) and low mean annual temperature (about 11°C). Zooid length demonstrated the strongest relationship with the range of seasonal variation in temperature rather than the mean annual temperature. Growth bands produced during colder months were less high than those produced during warmer months. Measurements of these alternating bands were used to calculate growth rate of the laminae, ranging from 20.7 at Plymouth to 29.3 mm year⁻¹ at Tino Island. Significant differences in zooid length were found between the two bands, with longer zooids within the band developed in colder months and shorter zooids in bands produced in the warmer period. We conclude that zooid size can be used as an environmental proxy of the seasonal temperature regimes experienced by the species.     

Essential and toxic elements in meat of wild and bred animals

Essential and toxic elements were determined by Energy Dispersive Polarized X-Rays Fluorescence Spectrometry (EDPXRF) in the meat of 145 wild and bred animals to provide the baseline data regarding meat of wild and bred animals consumed in central Italy. As far as K, Fe, Ni, Zn, and Cu are concerned, no significant differences resulted between young and adults and between males and females for farmed and wild animals. No marked differences were found between hunted and non-hunted animals groups. In all samples analyzed, Mn, Cr, and Mo were below the detection limit. As far as the non-essential or toxic elements are concerned, As, Cd, V, and Hg concentrations in muscle from wild and bred animals were low and always below the detection limits. Among the wild animals killed with lead (Pb) bullets, elevated Pb concentrations in tissues were detected. This finding may result in elevated Pb levels in meat ingested by humans.     

Effects of nano carbon black and single-layer graphene oxide on settlement,survival and swimming behaviour of Amphibalanus amphitrite larvae

The effects of two carbon-based nanomaterials, nano-sized carbon black (nCB), and single-layer graphene oxide (GO) on settlement of Amphibalanus amphitrite (Cirripedia, Crustacea) cypris larvae (cyprids) were assessed after 24, 48, and 72 h of exposure. Additionally, the effects of these nanomaterials on the mortality and swimming behaviour of the nauplius larvae (nauplii) of the same organism were determined after 24 and 48 h. The data indicate that nCB is more effective as a potential antisettlement agent than single-layer GO; moreover, nCB did not show any adverse effects on the larvae. The swimming behaviour of II stage nauplii of A. amphitrite exposed to a suspension of nCB was inhibited only at very high nCB concentrations (≥0.5 mg/mL). Single-layer GO, on the contrary, showed lower antisettlement effects and was more active in altering the survival and inhibiting the swimming behaviour of the nauplii. An indication of the toxic or non-toxic mechanisms of the antisettlement properties of both of these nanomaterials is provided by the reversibility of the antisettlement activity. In conclusion, we propose nCB as an innovative antifouling nanomaterial that shows low toxicity towards the model organism (crustaceans) used in this study.     

Isolation and identification of fungi tolerant to polycyclic aromatic hydrocarbons and coal tar from different habitats in Lithuania

A group of 36 fungal strains, belonging to the Lithuanian mycobiota, was collected and isolated from different locations, habitats, and matrices, including creosote-treated wood in storage yards for crosstie wastes. The eight most perspective strains selected according to preliminary assessment of tolerance to coal tar were subsequently identified combining taxonomical evaluation and molecular techniques. The tolerance of the eight identified fungal species (five basidiomycetes and three ascomycetes) to the presence of various concentrations of coal tar, and for the four most perspective fungal strains (Pleurotus sp., Schizophyllum sp., Irpex lacteus, Bjerkandera adusta) to polycyclic aromatic hydrocarbons was evaluated. The ligninolytic enzymatic activity assay of the isolated strains resulted in a good correspondence between the tolerance to pollutants and the capability to produce ligninolytic enzymes indicating that this group of white-rot fungi is perspective for further investigation and eventual usage for mycoremediation of polycyclic aromatic hydrocarbons polluted substrates.     

Prediction and assessment of ecogenotoxicity of antineoplastic drugs in binary mixtures

The combined genotoxic effects of four anticancer drugs (5-fluorouracil [5-FU], cisplatin [CDDP], etoposide [ET], and imatinib mesylate [IM]) were studied testing their binary mixtures in two crustaceans that are part of the freshwater food chain, namely Daphnia magna and Ceriodaphnia dubia. Genotoxicity was assessed using the in vivo comet assay. Assessment was based on two distinct effect sizes determined from dose-response experiments. Doses for single and combined exposures expected to result in these effect sizes were computed based on Bliss independence as reference model. Statistical comparison by analysis of variance of single and combined toxicities allowed accepting or rejecting the independency hypothesis. The results obtained for D. magna showed independent action for all mixtures except for IM+5-FU that showed an antagonistic interaction. In C. dubia, most mixtures had antagonist interactions except IM+5-FU and IM+CDDP that showed Bliss independence. Despite the antagonistic interactions, our results demonstrated that combinations of anticancer drugs could be of environmental concern because effects occur at very low concentrations that are in the range of concentrations encountered in aquatic systems.     

Bioherbicidal activity of a germacranolide sesquiterpene dilactone from Ambrosia artemisiifolia L.

Ambrosia artemisiifolia L. (common ragweed) is an invasive plant whose allelopathic properties have been suggested by its field behaviour and demonstrated through phytotoxicity bioassays. However, the nature of the molecules responsible for the allelopathic activity of common ragweed has not been explored. The main objective of this study was to identify the phytotoxic molecules produced by A. artemisiifolia. A preliminary investigation has indicated that a methanol extract of A. artemisiifolia completely inhibited the germination of cress and radish. Semi-preparative fractionation of the methanol extract allowed separating of phytotoxic fraction which contained a single compound. The structure of this compound was elucidated by liquid chromatography–mass spectrometry (LC-MS)/MS, high-resolution mass spectral, nuclear magnetic resonance, and Fourier transform infrared spectra as sesquiterpene lactone isabelin (C₁₅H₁₆O₄). The effect of pure isabelin was tested on four different weed species, confirming the inhibitory activity of molecule. The results indicate directions for the future studies about herbicidal specific activity of isabelin, as pure molecule or in the crude extract, as a potential candidate for biological weed control.     

Porewater as a matrix in toxicity bioassays with sea urchins and bivalves: evaluation of applicability to the Venice lagoon (Italy)

Porewater plays an important role in sediment toxicity assessment using bioassays, but the most reliable extracting method and the potential contribution of confounding factors to the real toxicity need to be studied. The applicability of bioassays with the early life stages of Paracentrotus lividus, Mytilus galloprovincialis and Crassostrea gigas on porewaters extracted by centrifugation from the Venice Lagoon (Italy) is evaluated and demonstrated: toxicity tests can discriminate the toxicity of porewaters from sites with different kinds and levels of pollution and, using toxicity scores, data are classified in five toxicity classes. Sulphides do not represent a confounding factor in porewater toxicity; in contrast ammonia exhibited some concentrations above the toxicity threshold for sea urchin embryos.