Field derived accumulation and release kinetics of DDTs in plants

Vegetation plays an important role in influencing the air/surface exchange of semivolatile organic compounds (SOCs). In order to predict the capability of different plant species to capture chemicals from the air, plant-air partition coefficients and kinetic accumulation parameters must be defined. In this study, potted plants of three different species were transferred to the vicinity of a source point for DDT, namely a contaminated area around a former production plant in Italy. Leaves were constantly sampled in order to follow the uptake from air over time. Later, the potted plants were transported to a location characterized by background diffuse air concentrations for the release phase. Coupling the experimental results with a two-compartment accumulation model it was possible to derive the kinetics parameters and the plant-air partition coefficient K(PA) for p,p'-DDT. The logK(PA) (on a mass/volume basis) ranged between 1.7 and 2.2 for the different species. The uncertainties related to the different phenomena involved in a field uptake/release experiment are discussed.     

Intrinsic vulnerability assessment of Sette Comuni Plateau aquifer (Veneto Region, Italy)

Maps illustrating the different degrees of vulnerability within a given area are integral to environmental protection and management policies. The assessment of the intrinsic vulnerability of karst areas is difficult since the type and stage of karst development and the related underground discharge behavior are difficult to determine and quantify. Geographic Information Systems techniques are applied to the evaluation of the vulnerability of an aquifer in the alpine karst area of the Sette Comuni Plateau, in the Veneto Region of northern Italy. The water resources of the studied aquifer are of particular importance to the local communities. This aquifer must therefore be protected from both inappropriate use as well as possible pollution. The SINTACS and SINTACS P(RO) K(ARST) vulnerability assessment methods have been utilized here to create the vulnerability map. SINTACS P(RO) K(ARST) is an adaptation of the parametric managerial model (SINTACS) to karst hydrostructures. The vulnerability map reveals vast zones (81% of the analyzed areas) with a high degree of vulnerability. The presence of well-developed karst structures in these highly vulnerable areas facilitate water percolation, thereby enhancing the groundwater vulnerability risk. Only 1.5 of the studied aquifer have extremely high-vulnerability levels, however these areas include all of the major springs utilized for human consumption. This vulnerability map of the Sette Comuni Plateau aquifer is an indispensable tool for both the effective management of water resources and as support to environmental planning in the Sette Comuni Plateau area.     

Populus alba dioctyl phthalate uptake from contaminated water

Environmental Science and Pollution Research - Phthalates are micro-pollutants of great concern due to their negative effects on ecosystem functioning and human health. Thanks to its capability in...     

Air pollution impact assessment on agroecosystem and human health characterisation in the area surrounding the industrial settlement of Milazzo (Italy): a multidisciplinary approach

In order to evaluate the impact of atmospheric pollutants emitted by the industrial settlement of Milazzo (Italy) on agriculture, sulphur dioxide and ozone levels in air were monitored and the data were used to estimate yield losses of the most widespread cultures. Trace element concentrations in crops and soils were also detected and metabolic profiles of soil microbial communities were considered. Vibrio fischeri test was used to appraise airborne pollutant ecotoxicity and epidemiological studies on causes of death distribution were carried out to characterize health state of people living in the area. All the sampling points were selected in farms on the basis of a theoretical meteo-diffusive model of industrial air pollutants. Experimental SO₂ and O₃ values mainly exceeded the threshold established by Italian and EU regulations to protect vegetation and they correspond to estimated significant crop losses. Conversely toxic element residues in soils and in agroalimentary products were generally lower than the fixed values. SO₂ and O₃ concentrations, toxic element contents and ecotoxicity levels of airborne pollutants were not related only to industrial site emissions, while the fluctuations on metabolic profiles of soil microbial communities seem to agree with the predicted deposition of xenobiotic compounds from the industrial plants. The epidemiological study evidenced a better health state of populations living in the investigated area than in the Messina province and the Sicily region but, inside the area, males living in the municipalities closest to the industrial settlement exhibited a worst health state than those in the very far ones.     

Leaching potential of some phenylureas and their main metabolites through laboratory studies

BACKGROUND, AIMS AND SCOPE: Laboratory studies were conducted with the aim of defining the leaching potential of some phenylureas and their metabolites. A first study was performed for calculating their leaching index (as GUS) on the base of intrinsic properties: persistence (as DT50) and mobility (as Koc) in soil. Another study consisted of aged column leaching experiments whose meaning was to semi-quantify the occurrence of the tested compounds in the leachates, so simulating in field conditions. METHODS: The tested compounds were: diuron, linuron and monolinuron (parents); 3,4-dichloroaniline (DCA), 4-chloroaniline (CLA), 1-(3,4-dichlorophenyl)-3-methylurea (DCPMU), 1-(3,4-dichlorophenyl)urea (DCPU), 1-(4-chlorophenyl)urea (CPU) and monuron, this latter considered both as a metabolite and parent compound. The Koc values of the examined substances were determined by the HPLC screening methods, according to the OECD TG 121. DT50 determinations and aged column leaching experiments were carried out according to SETAC procedures. RESULTS AND DISCUSSION: The examined compounds showed a rather wide range of persistence in soil, with DT50 values less than 2 days for DCA and CLA, close to 8 days for DCPU and CPU and from 16 (diuron) up to 24.8 (DCPMU) days for the others. Their mobility was generally high, based on their Koc values, which ranged from 33 (CPU) to 406 (linuron). The GUS indices indicated that monuron has a clear potential to contaminate groundwater (> 2.8); DCPMU, monolinuron, CPU and diuron are intermediate contaminants (1.8-2.8). Linuron, DCPU, CLA and DCA exhibited a non-leaching behaviour (< 1.8). The aged leaching column experiments showed that parents were found in the leachates at very high percentages respect to the doses applied. The metabolites reached much less percentages, the highest values were observed for monuron from diuron (5.7), CPU (7.2) and DCPMU (8.2%). CONCLUSION: Diuron, Monuron, CPU and DCPMU on the basis of their intrinsic properties, formation from their parents and occurrence in leachates from aged column leaching studies, seem to possess the characteristics of groundwater contaminants. The methodological approach of this study is relatively easy and rapid, hence it can represent a tool for a first screening of compounds such as pesticide metabolites (generally available only in small quantities and for which a field study is not conceivable) or other compounds for which not adequate environmental data are available.     

Blends of Poly (Butylene Adipate-Co-Terephthalate) and Thermoplastic Whey Protein Isolate: A Compatibilization Study

Journal of Polymers and the Environment - This work assesses the influence of the plasticizer polyethylene glycol (PEG) on the compatibilization of poly (butylene adipate-co-terephthalate) (PBAT)...     

Climate-induced reaction norms for life-history traits in pythons

Climate change modelers predict increasingly frequent "extreme events," so it is critical to quantify whether organismal responses (such as reproductive output) measured over the range of usual climatic conditions can predict responses under more extreme conditions. In a 20-year field study on water pythons (Liasis fuscus), we quantified the effects of climatically driven annual variation in food supply on demographic traits of female pythons (feeding rate, body size, body mass, and reproductive output). Reaction norms linking food supply to feeding rates and residual body mass were broadly linear, whereas norms linking food supply to female body size became curvilinear when a dramatic (flooding-induced) famine reduced the mean body size at sexual maturity. Thus, the reaction norms recorded over 16 years of mal" (albeit highly variable) climatic conditions gave little insight into the population's response to a more extreme nutritional crisis.     

Saharan dust contribution to PM₁₀, PM₂.₅ and PM₁ in urban and suburban areas of Rome: a comparison between single-particle SEM-EDS analysis and whole-sample PIXE analysis

From February 15th to April 15th 2009, a period characterised by two episodes of Saharan dust outbreaks in Italy, particulate matter (PM) samples were collected at two stations (urban and suburban) in Rome. Some samples were selected and analysed using the SEM-EDS technique to characterise PM, focussing especially on the mineral contribution. Samples were representative both of days affected by Saharan dust episodes and days without this contribution. Cluster analysis allowed the attribution of each of about 67,000 analysed particles to one of the seven main statistical groups based on their composition. Characteristics of the particulate components identified using SEM-EDS analysis were verified by PIXE analysis carried out on filters collected in a suburban area. Ultimately, the contribution of crustal particles was revealed to be consistently high, highlighting the importance of local and regional mineral contributions, as well as those of Saharan origin. Therefore, quantifying all mineral contributions to resuspended particulate could lead to significant reductions of the PM level also on days not influenced by Saharan dust, thus limiting conditions when PM?? daily limit value (DLV) established by European legislation is exceeded.