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31.
Summary. Two Ceratosoma species, C. trilobatum and C. gracillimum (Mollusca: Gastropoda: Opistobranchia), collected along the South China Sea coast, have been studied in order to investigate their defensive strategies. Both species contain four typical sponge furanosesquiterpenoids, probably with a dietary origin. The tissue distribution of these compounds has been studied by 1H-NMR analysis and preliminary bioassays have been carried out in order to evaluate the ecological role of the isolated metabolites. The main sesquiterpene component in both species was (–)-furodysinin (2), which showed significant feeding-deterrent and ichthyotoxic properties in bioassays with freshwater organisms. The work has been performed studying a very limited number of molluscs that prevented the realization of ecologically relevant experiments. However, the almost exclusive presence of compound 2 in the crude extract of the mantle glands concentrated in the dorsal horn of C. gracillimum strongly supports the defensive role of that dorsal protuberance, which probably acts as a defensive lure attracting potential predators to the part of the animal that contains the distasteful chemicals.  相似文献   
32.
The present investigation was carried out on the bluefin tuna (Thunnus thynnus) collected during the month of April 2003 from the Straits of Messina. The aim of this study is to determine heavy metal levels (Cd, Cu, Hg, Mn, Pb and Zn) in liver and muscle tissues of 14 Thunnus thynnus of different age and sex and to investigate the relationships between fish sex and size (length and weight and metal concentrations in the tissues. The concentrations of the various metals were determined by a Varian atomic absorption spectroscopy instrument. The results showsignificant variations (p < 0.01) for Hg and Zn concentrations in muscle than in liver samples. Concentrations of Cd and Pb are below the instrumental detection limits in almost all muscle samples. Levels of Hg (3.03 + 0.55 μg/g) are above the MRLs only in muscle (1μg/g) establishing toxicological risks for the consumer. Regression analysis shows a negative correlation between mercury level and weight and length in samples from both female and male. No significant difference between mean heavy metals concentrations and male or female tuna is seen. For greater food safety, it would be advisable to reduce the mercury intake by selecting safer fish, species and size and by the avoidance of tuna fish consumption by pregnant women, young children and old people, who are more sensitive to mercury exposure.  相似文献   
33.
The toxicity of leachates from two municipal solid waste (MSW) landfills in Southern Italy was characterized using a toxicity identification evaluation procedure. The chemical and physical fractionation techniques were: pH adjustment, pH adjustment/filtration, pH adjustment/C(18) solid phase extraction, graduated pH and EDTA chelation. All the samples exhibited acute toxicity towards the bacterium Vibrio fischeri, the freshwater rotifer Brachionus calyciflorus and the freshwater crustaceans Thamnocephalus platyurus and Daphnia magna. Statistical techniques were used to determine the discriminatory power and the toxicity detection capacity of the different assays and to choose a minimal battery of tests for the toxicity identification of leachates. Toxicity was closely associated with pH, generally increasing at higher pH levels and decliming at lower ones. Furthermore, results showed that toxicants could be characterized as cations, basic chemicals, suspended solids and apolar compounds.  相似文献   
34.
This study was designed to assess toxic and genotoxic compounds in the urban air of Caserta, South Italy using cuttings from the plant Tradescantia #4430. In situ monitoring of gaseous pollutans was made at 17 sampling points in two seasons of the year. Genotoxicity was evaluated by recording the micronuclei in meiotic pollen mother cells (Trad-MCN assay). In addition, the passive sampler semipermeable membrane devices (SPMDs) were deployed at the sampling points with a significant increase in micronuclei frequency. SPMDs concentrated priority organic pollutants were identified by high performance liquid chromatography and gas chromatography, while toxicity and mutagenesis were assessed on the bacterium Vibrio fischeri using the Microtox and Mutatox systems respectively. Significant toxic and mutagenic effects were observed at different points on the town grid and SPMDs effectively concentrated trace contaminants. The relationship between what was present in the air sampled by SPMDs and the micronuclei frequency was also explored.  相似文献   
35.
Increased awareness of the importance of environmental protection and the introduction of international standards like ISO 14001 stimulated development of environmental sustainability indicators as a means to measure systems environmental performance. Here, a thermodynamic approach, emergy analysis (Odum, 1988) was used to obtain sustainability indicators able to analyse and quantify the productive and ecological performance of four famous Italian wine productions: Chianti, Brunello di Montalcino, Nobile di Montepulciano, and Barbera d'hti. The application to agricultural production was motivated by the growing need for productive and environmentally sound development in modern agriculture, in which the resource base, the environment, is preserved. The choice of wines, more precisely, grape production, is due to their importance for Italian agriculture and the economy. All the wines demonstrated a good long-term environmental sustainability, especially in view of their high quality and in comparison with the average Italian wine production. Emergy analysis proved a powerful tool for assessing environmental performance of these systems, and its use could easily be extended to other wine productions to obtain a form of environmental performance classification of this product. Systematic use of emergy analysis to assess environmental performance of different processes and products, not necessarily in agriculture, could be useful for environmental certification.  相似文献   
36.
A simple and sensitive validated analytical method based on liquid chromatography coupled to tandem fluorescence (FD) and ultraviolet (UV) spectrophotometry was applied to monitor the presence of bisphenol A and bisphenol S in plastic baby bottles marketed in Italy. The limits of detection (LOD) were 3.75 ng mL?1 and 80.00 ng mL?1, and those of quantification (LOQ) were 12.51 ng mL?1 and 260.00 ng mL?1 for BPA (FD detection) and for BPS (UV detection), respectively. BPA was found in only four samples, two samples undergone to microwave heating and two samples undergone to bottle warmer heating either at 40°C or at 80°C. Although the quantities of leached BPA were well below the reference dose for daily intake established by the European Food Safety Authority (EFSA) (4.0 µg kg?1 bw/day), the release of BPA and BPS from these plastic materials should be carefully considered by the government authorities to increase people's awareness on this issue and to protect the most vulnerable population group.  相似文献   
37.
Shifts in government priorities in response to the 2007 global recession have affected wildfire management and natural disaster funding arrangements, leading to a reduced effectiveness of fire suppression actions and increasing fire vulnerability. Our study investigates the role of local socioeconomic contexts on fire suppression effectiveness under economic expansion and recession in a Mediterranean region (Attica, Greece) strongly affected by 2007 crisis and displaying a persistently high density of peri-urban wildfires. Basic characteristics of wildfires (spatial distribution, intensity, and land use preferences) were investigated in the study area over two consecutive 8-year time intervals characterized by economic expansion (2000–2007) and recession (2008–2015). An integrated approach based on multivariate statistics and artificial neural networks was implemented to evaluate latent relationships between fire suppression time, wildfire characteristics, and socioeconomic dynamics. Controlling for wildfires’ characteristics over the two time intervals, fire time length increased under crisis—mainly for small and medium-sized fires—possibly as an indirect response to reduced effectiveness of forest land management. Local contexts and political decisions influenced by economic downturns are relevant factors shaping wildfires’ severity in the Mediterranean region. With recession, local contexts vulnerable to wildfires require more effective fire prevention measures, sustainable forest management, and regional planning.  相似文献   
38.
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.  相似文献   
39.
40.
The Mar Piccolo of Taranto (Ionian Sea, Southern Italy) is a semi-enclosed and strongly polluted basin. For decades, it has been subjected to different anthropogenic impacts. These stressors caused severe sediments contamination with high concentration of different pollutants (PAHs, PCB, heavy metals). In order to assess the current status of sediments contamination, an ecotoxicological investigation combined with chemical analysis (heavy metals, PAH, and PCB) has been performed. In order to derive ecologically relevant conclusions, a multiorganisms and multiend-points approach has been applied, exposing organisms from different trophic levels to elutriate and whole sediment. The battery of bioassays consists of a microalgal growth inhibition test (Dunaliella tertiolecta), acute and sublethal assays (end-points: mortality, immobilization and swimming speed alteration) on crustaceans larvae and juveniles, and rotifers (Amphibalanus amphitrite, Artemia salina, Corophium insidiosum and Brachionus plicatilis), and embryotoxicity test on echinoderms (Paracentrotus lividus). Considering the high levels of sediment contamination highlighted from chemical analysis, an unexpected very low toxic effect was observed, even considering the sublethal end-point (larval swimming speed alteration). The results of this study suggest a very complex contaminants dynamic in the Mar Piccolo sediments that, despite a strong level of contamination, seems to not affect in a proportional manner the biological compartment.  相似文献   
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