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51.
In this study, a spatial and temporal survey at three sites located in the "canals" of the Venice historic centre (Italy) and at a reference site was undertaken to evaluate stress effects on mussels sampled in the Venice urban area, where raw sewage is discharged without treatment directly into the water. A battery of biomarkers (metallothionein, micronuclei, condition index and survival in air) was used to evaluate the stress condition of the animals. At the same time the alkali-labile phosphate assay (ALP) was performed in mussel' hemolymph with the aim to find an estrogenic effect biomarker in this mussel species. Biomarker results showed an impairment of the general health condition in the mussels coming from the urban area, in agreement with the chemical analysis. Significantly higher level of the ALP was found in male mussels sampled in April in the urban area, in comparison with the ones from the reference site (P<0.001). Finally, the PCA proved an easy and useful tool to summarize the obtained results, also able to classify the data to indicate a pollution gradient in the Venice urban area.  相似文献   
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In this paper we describe the construction and use of a set of bioluminescent yeast strains for the detection of compounds that can affect androgen or estrogen receptor mediated hormonal signalling. The set includes Saccharomyces cerevisiae strains expressing human androgen receptor (AR), estrogen receptor alpha (ERalpha) or estrogen receptor beta (ERbeta), along with firefly luciferase controlled by a respective hormone responsive promoter. A constitutively luminescent strain was included in the set for determining the cytotoxicity of the sample. Yeast cells were incubated with pure chemicals or complex samples for 2.5 h, after which the signal could be detected from the cell-sample mixture after simply adding the D-luciferin substrate. The assays could be completed in one day and they required no cell lysis or centrifugation steps, which makes them suitable for high-throughput analysis of samples. Due to a short incubation time the assays are directly applicable to different sample matrices, requiring no pretreatment of the samples. The assays were used to assess the hormonal activity in moisturizing lotions as an example of a complex sample matrix known to contain endocrine disrupting chemicals. Six out of eight tested moisturisers showed high estrogenic activity, whereas no androgenic activity was observed in the samples.  相似文献   
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In 1997, the National Highway Traffic Safety Administration amended its requirements for frontal crash performance under Federal Motor Vehicle Safety Standard 208 to temporarily allow 30 mi/h (48 km/h) sled tests with unbelted dummies as an alternative to 30 mi/h head-on rigid-barrier vehicle tests. This change permitted automakers to reduce airbag inflation forces so that they would be less likely to injure occupants who are close to airbags when they first deploy. Most vehicle models were sled-certified starting in model year 1998. Airbag-related deaths have decreased since 1997; however, controversy persists about whether reduced inflation forces might be decreasing protection for some occupants in high-severity frontal crashes. To examine the effects of the regulatory changes, this study computed rate ratios (RR) and 95% confidence intervals (95% CI) for passenger vehicle driver deaths per vehicle registration during 2000-2002 at principal impact points of 12 o'clock for 1998-99 model year vehicles relative to 1997 models. Passenger vehicles included in the study had both driver and passenger front airbags, had the same essential designs during the 1997-1999 model years, and had been sled-certified for drivers throughout model years 1998 and 1999. An adjustment was made for the higher annual mileage of newer vehicles. Findings were that the effect of the regulatory change varied by vehicle type. For cars, sport utility vehicles, and minivans combined, there was an 11 percent decrease in fatality risk in frontal crashes after changing to sled certification (RR = 0.89; 95% CI = 0.82-0.96). Among pickups, however, estimated frontal fatality risk increased 35 percent (RR = 1.35; 95% CI = 1.12-1.62). For a broad range of frontal crashes (11, 12, and 1 o'clock combined), the results indicated a modest net benefit of the regulatory change across all vehicle types and driver characteristics. However, the contrary finding for pickups needs to be researched further.  相似文献   
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This paper reports, for the first time, the concentrations of selected phthalates in drinking water consumed in Portugal. The use of bottled water in Portugal has increased in recent years. The main material for bottles is polyethylene terephthalate (PET). Its plasticizer components can contaminate water by leaching, and several scientific studies have evidenced potential health risks of phthalates to humans of all ages. With water being one of the most essential elements to human health and because it is consumed by ingestion, the evaluation of drinking water quality, with respect to phthalate contents, is important. This study tested seven commercial brands of bottled water consumed in Portugal, six PET and one glass (the most consumed) bottled water. Furthermore, tap water from Lisbon and three small neighbor cities was analyzed. Phthalates (di-n-butyl phthalate ester (DnBP), bis(2-ethylhexyl) phthalate ester (DEHP), and di-i-butyl phthalate ester (DIBP)) in water samples were quantified (PET and glass) by means of direct immersion solid-phase microextraction and ionic liquid gas chromatography associated with flame ionization detection or mass spectrometry due to their high boiling points and water solubility. The method utilized in this study showed a linear range for target phthalates between 0.02 and 6.5 μg L?1, good precision and low limits of detection that were between 0.01 and 0.06 μg L?1, and quantitation between 0.04 and 0.19 μg L?1. Only three phthalates were detected in Portuguese drinking waters: dibutyl (DnBP), diisobutyl (DIBP), and di(ethylhexyl) phthalate (DEHP). Concentrations ranged between 0.06 and 6.5 μg L?1 for DnBP, between 0.02 and 0.16 μg L?1 for DEHP, and between 0.1 and 1.89 μg L?1 for DIBP. The concentration of DEHP was found to be up to five times higher in PET than in glass bottled water. Surprisingly, all the three phthalates were detected in glass bottled water with the amount of DnBP being higher (6.5 μg L?1) than in PET bottled water. These concentrations do not represent direct risk to human health. Regarding potable tap water, only DIBP and DEHP were detected. Two of the cities showed concentration of all three phthalates in their water below the limits of detection of the method. All the samples showed phthalate concentrations below 6 μg L?1, the maximum admissible concentration in water established by the US Environmental Protection Agency. The concentrations measured in Portuguese bottled waters do not represent any risk for adult's health.  相似文献   
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Most of the current knowledge on Mediterranean gorgonians is restricted to investigations of those populations found within shallow sublittoral waters, and only limited data are available for populations located below scuba depth. To overcome this lack of information, the occurrence and abundance of the gorgonians Eunicella singularis, Paramuricea clavata, and Leptogorgia sarmentosa were investigated in northwestern Mediterranean benthic communities over a wide geographical (60 km of coastline) and bathymetrical (0–70 m deep) extent using a remotely operated vehicle (ROV). The greatest occurrence and abundances of E. singularis and P. clavata were concentrated in areas that are directly exposed to strong near-bottom currents. E. singularis was the most common and abundant species and displayed great plasticity and amplitude in its environmental preferences. Conversely, P. clavata showed a very patchy distribution that was associated with vertical rocky walls. Only isolated colonies of L. sarmentosa were observed in the study area. Hot spots of abundance of E. singularis and P. clavata were identified below a depth of 40 m, which demonstrates the importance of studying the distribution of benthic species over a wide geographical and bathymetrical extent.  相似文献   
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In recent years, the unregulated increase of the population in coastal areas of developing countries has become source of concern for both water supply and quality control. In the region of Dakar (Senegal), approximately 80% of water resources come from groundwater reservoirs, which are increasingly affected by anthropogenic pressures. The identification of the main sources of pollution, and thus the aquifer vulnerability, is essential to provide a sound basis for the implementation of long-term geochemically based water management plans in this sub-Saharan area. With this aim, a hydrochemical and isotopic survey on 26 wells was performed in the so-called Peninsula of Cap-Vert. Results show that seawater intrusion represents the main process affecting groundwater chemical characteristics. Nitrates often exceed the World Health Organization drinking water limits: stable isotopes of dissolved nitrate ( $\updelta ^{15}$ N and $\updelta ^{18}$ O) indicate urban sewage and fertilizers as a major source of contamination. Results depict a complex situation in which groundwater is affected by direct and indirect infiltration of effluents, mixing with seawater and freshening processes from below. Besides the relevance of the investigation at a regional level, it represents a basis for decision-making processes in an integrated water resources management and in the planning of similar monitoring strategies for other urban coastal regions.  相似文献   
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