Modelling assessment of PM10 exposure control policies in Northern Italy

To assess the impact of three different emission reduction scenarios on PM10 concentrations in Northern Italy, the TCAM multiphase model has been applied in the framework of the CityDelta III-CAFE EU project. The considered domain, that is characterized by high urban and industrial emissions and a dense road traffic, due to frequently stagnating meteorological conditions is often affected by severe PM10 levels, far from the European standard regulations. The impact evaluation has been performed in terms of both yearly mean values and 50 g/m³ exceedance days for the 2004 Base Case simulation. The results show that the three selected emission reduction scenarios up to 2020 improve air quality all over the domain, in particular, in the area with higher emission density.     

A stochastic Lagrangian micromixing model for the dispersion of reactive scalars in turbulent flows: role of concentration fluctuations and improvements to the conserved scalar theory under non-homogeneous conditions

Several reaction schemes, based on the conserved scalar theory, are implemented within a stochastic Lagrangian micromixing model to simulate the dispersion of reactive scalars in turbulent flows. In particular, the formulation of the reaction-dominated limit (RDL) reaction scheme is here extended to improve the model performance under non-homogeneous conditions (NHRDL scheme). The validation of the stochastic model is obtained by comparison with the available measurements of reactive pollutant concentrations in a grid-generated turbulent flow. This test case describes the dispersion of two atmospheric reactant species (NO and O₃) and their reaction product (NO₂) in an unbounded turbulent flow. Model inter-comparisons are also assessed, by considering the results of state-of-the-art models for pollutant dispersion. The present validation shows that RDL reaction scheme provides a systematic overestimation (relative error of ca. 85% around the centreline) in computing the local reactant consumption/production rate, whereas the NHRDL scheme drastically reduces this gap (relative error lower than 5% around the centreline). In terms of NO₂ production (or reactant consumption), neglecting concentration fluctuations determines overestimations of the product mean of around 100% and a NO₂ local production of one order of magnitude higher than the reference simulation. In terms of standard deviations, the concentration fluctuations of both the passive and reactive scalars are generally of the same order of magnitude or up to 1 or 2 orders of magnitudes higher than the corresponding ensemble mean values, except for the background reactant close to the plume edges. The study highlights the importance of modelling pollutant reactions depending on the instantaneous instead of the mean concentrations of the reactants, thus quantifying the role of the turbulent fluctuations of concentration, in terms of scalar statistics (mean, standard deviation, intensity of fluctuations, skewness and kurtosis of concentration, segregation coefficient, simulated reaction rate). This stochastic particle method represents an efficient numerical technique to solve the convection–diffusion equation for reactive scalars and involves several application fields: micro-scale air quality (urban and street-canyon scales), accidental releases, impact of odours, water quality and fluid flow industrial processes (e.g. combustion).     

Triclocarban: UV photolysis,wastewater disinfection,and ecotoxicity assessment using molecular biomarkers

Triclocarban (TCC) is an antibacterial agent found in pharmaceuticals and personal care products (PPCP). It is potentially bioaccumulative and an endocrine disruptor, being classified as a contaminant of emerging concern (CEC). In normal uses, approximately 96% of the used TCC can be washed down the drain going into the sewer system and eventually enter in the aquatic environment. UV photolysis can be used to photodegrade TCC and ecotoxicity assays could indicate the photodegradation efficiency, since the enormous structural diversity of photoproducts and their low concentrations do not always allow to identify and quantify them. In this work, the TCC was efficiently degraded by UVC direct photolysis and the ecotoxicity of the UV-treated mixtures was investigated. Bioassays indicates that Daphnia similis (48 h EC₅₀ = 0.044 μM) was more sensitive to TCC than Pseudokirchneriella subcapitata (72 h IC₅₀ = 1.01 μM). TCC and its photoproducts caused significant effects on Eisenia andrei biochemical responses (catalase and glutathione-S-transferase); 48 h was a critical exposure time, since GST reached the highest activity values. UVC reduced the TCC toxic effect after 120 min. Furthermore, TCC was photodegraded in domestic wastewater which was simultaneously disinfected for total coliform bacterial (TCB) (360 min) and Escherichia coli (60 min).

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Graphical abstract TCC degradation and ecotoxicological assessment

     

Occurrence and distribution of six selected endocrine disrupting compounds in surface- and groundwaters of the Romagna area (North Italy)

Environmental Science and Pollution Research - Endocrine disrupting compounds (EDCs) are a wide group of contaminants of emerging concern known to be harmful for organisms. The aim of the study was...     

A Cost-Effectiveness Analysis of Seminatural Wetlands and Activated Sludge Wastewater-Treatment Systems

A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation was established to solve the problem of the different levels of dilution that characterize the inflow water of the different systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services, and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of 2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed. In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered.

Photodegradation of pentachlorophenol catalyzed by semiconductor particles

The heterogeneous photocatalytic degradation of pentachlorophenol (PCP) in aqueous solutions containing a suspension of TiO₂ leads to the quantitative formation of CO₂ and HC1. The photodegradation has also been studied in other semiconductor dispersions such as ZnO, CdS, WO₃, and SnO₂. TiO₂ appears the most efficient. Oxygen and water are essential ingredients in the complete mineralization of this pollutant found near pulp and paper industries. Experiments with sunlight show a promising route for the water treatment processes; the half life of PCP (initial concentration 4.5 × 10^?5M) is about 8 minutes, in the presence of 2 g/l of TiO₂.     

First age and growth estimates in the deep water shark, <Emphasis Type="Italic">Etmopterus Spinax</Emphasis> (Linnaeus, 1758), by deep coned vertebral analysis

The velvet belly Etmopterus spinax (Linnaeus, 1758) is a deep water bottom-dwelling species very common in the western Mediterranean sea. This species is a portion of the by-catch of the red shrimps and Norway lobsters otter trawl fisheries on the meso and ipo-bathyal grounds. A new, simple, rapid, and inexpensive vertebral preparation method was used on a total of 241 specimens, sampled throughout 2000. Post-cranial portions of vertebral column were removed and vertebrae were prepared for ageing readings. Band pair counts ranged from 0 to 9 in females, and from 0 to 7 in males. Von Bertalanffy growth equations estimated for both sexes suggested a higher longevity for females (males: L _∞ = 394.3 mm k = 0.19 t ₀ = −1.41 L ₀ = 92.7 mm A ₉₉ = 18.24 years; females: L _∞ = 450 mm k = 0.16 t ₀ = −1.09 L ₀ = 72 mm A ₉₉ = 21.66 years). Age estimations are discussed in the context of deep water shark species. This is the first successful attempt at delineating faint growth bands in the poorly calcified deep coned vertebrae of E. spinax. This technique may be used in other difficult poorly calcified species.     

Humerus and femur length in fetuses with down syndrome

The aim of the study was to assess the value of sonographic measurement of fetal humerus and femur lengths in the second trimester as a screening tool for Down syndrome (DS). We reviewed retrospectively fetal sonographic biometry made at the time of amniocentesis between 15 and 19 weeks. The study group consisted of 27 DS fetuses. The control group comprised 500 normal fetuses chosen randomly. The expected humeral and femoral lengths for a given biparietal diameter were estimated by linear regression equations from the 500 normal fetuses. Receiver operating characteristic curve analysis was performed to evaluate both the detection rate and the false-positive rate of different cut-off values of measured to expected lengths ratios. The median femur and humeral lengths in DS fetuses were 0·91 times the expected values. No significant differences in the detection rate and false-positive rate were found between the humerus and femur lengths. When the humeral and femoral lengths were combined, we observed a remarkable reduction in the false-positive rate. A measured to expected length ratio of 0·91 detected 44·4 per cent of DS fetuses with 7·6 per cent false positives. These results suggest that the combination of femoral and humeral lengths may permit a more efficient use of ultrasound in screening for Down syndrome than the use of either alone.     

Modeling Pareto efficient PM10 control policies in Northern Italy to reduce health effects

High PM10 concentrations can cause human health problems, both related to short-term and long-term exposure to particles. In this work the impact of efficient PM10 control problems in Northern Italy is assessed by means of a two-stage methodology. In the first stage a multi-objective optimization approach is applied. The multi-objective problem defines two control objectives (the emission reduction costs and the air quality index) to be minimized varying the decision variables (precursor emission reductions). The solution of the multi-objective problem is the Pareto efficient PM10 control policies. In the second stage, the ExternE methodology is applied to estimate health impacts and external costs for the efficient emission reduction scenarios computed in the first stage. The methodology has been applied over Lombardia region, one of the most polluted areas in Europe.