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71.
The present study evaluates the relationship between Acid Volatile Sulfides (AVS) and metal accumulation in invertebrates with different feeding behavior and ecological preferences. Natural sediments, pore water and surface water, together with benthic and epibenthic invertebrates were sampled at 28 Flemish lowland rivers. Different metals as well as metal binding sediment characteristics including AVS were measured and multiple regression was used to study their relationship with accumulated metals in the invertebrates taxa.Bioaccumulation in the benthic taxa was primarily influenced by total metal concentrations in the sediment. Regarding the epibenthic taxa metal accumulation was mostly explained by the more bioavailable metal fractions in both the sediment and the water. AVS concentrations were generally better correlated with metal accumulation in the epibenthic invertebrates, rather than with the benthic taxa. Our results indicated that the relation between AVS and metal accumulation in aquatic invertebrates is highly dependent on feeding behavior and ecology.  相似文献   
72.
A review of ozone pollution in Italy shows levels largely above the thresholds established by EU regulation for vegetation and human health protection. The Italian air quality monitoring network appears quantitatively inadequate to cover all the territorial surface, because of scarcity and unequal distribution of monitoring sites. By applying the integrated assessment model RAINS-Italy to the year 2000, the whole of Italy exceeds the AOT40 critical level for forest, while Northern and central areas show strong potential of O3 impact on human health with ∼11% of territory >10 O3-induced premature deaths. Two scenarios for the year 2020, the Current Legislation and the Maximum Technical Feasible Reduction, show a reduction of AOT40Forest by 29% and 44%, SOMO35 by 31% and 47%, and O3-induced premature deaths by 32% and 48%, compared to 2000. RAINS-Italy can be used to improve the map quality and cover areas not reached by the national monitoring network.  相似文献   
73.
BackgroundPhthalates, reproductive toxicants in animals, are synthetic chemicals with ubiquitous human exposures because of their extensive use, with potential detrimental health effects. Infants are considered to represent a population at increased risk, as they are exposed early in life to several different sources of exposure to phthalates.Objectives and methodsLittle information exists on phthalate exposure through breast milk from different geographic areas. By means of a LC/LC–MS/MS method we tested the presence of several different phthalate metabolites in breast milk from 62 healthy mothers living in Southern Italy.ResultsThe simple monoesters mono-isobutyl phthalate (MiBP) (median 18.8 μg/l) and mono(2-ethylhexyl) phthalate (MEHP) (median 8.4 μg/l) were present in all milk samples, whereas mono-n-butyl phthalate (MnBP) (median 1.5 μg/l) and mono-benzyl phthalate (MBzP) (median < 0.3 μg/l) were found in 64.5% and 43.5% of the samples, respectively. Among the oxidative metabolites of DEHP and DiNP only mono(2-ethyl-5-carboxypentyl) phthalate (5cx-MEPP) and monoisononyl phthalate with one hydroxyl group (OH-MiNP) were detectable in one and 13 samples (21%), respectively.ConclusionsThese findings indicate that exposure to phthalates through breast milk in Southern Italian infants is comparable to that of other countries, thus confirming that human milk may represent an additional potential source of phthalate exposure in a population at increased risk. However, different milk concentrations of MiBP may suggest a different pattern of usage of di-iso-butyl phthalate in Europe, as compared to USA, whereas for the first time, we detected an oxidative DiNP metabolite, whose significance remains unclear.  相似文献   
74.
To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R= 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R= 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.  相似文献   
75.
Safety analysis like the HAZOP (HAZard OPerability) study can be much more efficient if a dynamic model of the system under consideration is available to evaluate the consequences of hazard deviations and the efficiency of the proposed safety barriers. In this paper, a dynamic model of a three-phase catalytic slurry intensified continuous chemical reactor is used within the context of its HAZOP (HAZard OPerability) study. This reactor, the RAPTOR®, is an intensified continuous mini-reactor designed by the French company AETGROUP SAS that can replace batch or fed-batch processes in the case of highly exothermic reactions involving hazardous substances. The highly hazardous hydrogenation of o-cresol under high pressure and temperature is taken as an example of application. Deviations as a temperature increase of the cooling medium or no cooling medium flow can produce an overheating of the reactor. Thus, three possible safety barriers are evaluated by simulation: shut off the gaseous reactant feed, shut off the liquid reactant feed or stop the agitation. The more efficient actions are the stopping of the agitation and/or of the gas reactant feed. The simulation results can efficiently help the reactor design and optimisation. Safety analysis can also be one of the criteria to compare batch and intensified continuous processes.  相似文献   
76.
In the last two decades, there has been a rich debate about the environmental degradation that results from exposure to solid urban waste. Growing public concern with environmental issues has led to the implementation of various strategic plans for waste management in several developed countries, especially in the European Union. In this paper, the relationships were assessed between economic growth, renewable energy extraction and greenhouse gas (GHG) emissions in the waste sector. The Environmental Kuznets Curve hypothesis was analysed for the member states of the European Union, in the presence of electricity generation, landfill and GHG emissions for the period 1995 to 2012. The results revealed that there is no inverted-U-shaped relationship between income and GHG emissions in European Union countries. The renewable fuel extracted from waste contributes to a reduction in GHG, and although the electricity produced also increases emissions somewhat, they would be far greater if the waste-based generation of renewable energy did not take place. The waste sector needs to strengthen its political, economic, institutional and social communication instruments to meet its aims for mitigating the levels of pollutants generated by European economies. To achieve the objectives of the Horizon 2020 programme, currently in force in the countries of the European Union, it will be necessary to increase the share of renewable energy in the energy mix.  相似文献   
77.
Scale-up of anodic oxidation system is critical to the practical application of electrochemical treatment in bio-refractory organic wastewater treatment. In this study, the scale-up of electrochemical flow system was investigated by treating petrochemical wastewater using platinized titanium (Ti/Pt) and boron-doped diamond (BDD) anodes. It was demonstrated that flow cell was successfully scaled-up because when it was compared with batch mode (Rocha et al. 2012b), higher performances on organic matter removal were achieved. Under the suitable operating conditions and better anode material, the chemical oxygen demand (COD) of petrochemical wastewater was reduced from 2,746 to 200 mg L?1 within 5 h with an energy consumption of only 56.2 kWh m?3 in the scaled-up BDD anode system. These results demonstrate that anode flow system is very promising in practical bio-refractory organic wastewater treatment.  相似文献   
78.
The majority of ecotoxicological enclosure experiments monitor species abundances at different chemical concentrations. Here, we present a new modelling approach that estimates changes in food web flows from such data and show that population- and food web level effects are revealed that are not apparent from abundance data alone. For the case of cypermethrin in freshwater enclosures, photosynthesis and excretion (d−1) of phytoplankton at 3.643 μg L−1 cypermethrin were 30% lower and 100% higher than in the control, respectively. The ingestion rate of mesozooplankton (d−1) was 6 times higher in the treated enclosures than in the control as food concentration increased with insecticide exposure. With increasing cypermethrin concentrations, nanoflagellates progressively relied on phytoplankton as their main food source, which rendered the food web less stable. We conclude that this tool has excellent potential to analyse the wealth of enclosure data as it only needs species abundance and general constraints.  相似文献   
79.
80.
The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way.  相似文献   
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