Sources and behaviour of polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in Spanish sewage sludge

Presence, sources and behaviour of polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were evaluated in Spanish sewage sludge. A total of 120 samples were seasonally collected from October 2005 to September 2006 at 31 urban wastewater treatment plants (WWTPs). Concentrations of PBDEs (ranging between 57.5 and 2606 ng/g dry weight) were two to three orders of magnitude higher than those obtained for PCDDs (0.17-5.03 ng/g d.w.) and PCDFs (0.05-3.07 ng/g d.w.). All the samples presented International Toxicity Equivalents (I-TEQ) levels (ranging between 2.06 and 44.4 ng/kg d.w.) below the limit values proposed by European Union for land application. Congener patterns evaluation revealed that the use of Deca-BDE commercial mixture seems to be the major source of PBDEs in the sludge. Nevertheless, origin of PCDD/Fs should be related to atmospheric deposition, faeces and presence of PCDD/Fs precursors such as pentachlorophenol in the sludge. No correlations (p > 0.05) were found between pollutant concentrations (PBDEs and PCDD/Fs) and wastewater treatment plant (WWTP) characteristics (capacity nor sludge rate). Lower levels of PBDEs and PCDFs were found in WWTPs using biological nitrogen and phosphorous elimination, suggesting that these compounds are susceptible of microbial elimination. According to our knowledge, this is the first work comparing together both PBDEs and PCDD/Fs sludge patterns.     

Measurement of machinery safety level: European framework for product control: Particular case: Spanish framework for market surveillance

Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced.     

Applying Fuzzy Logic to Assess Human Perception in Relation to Conservation Plan Efficiency Measures Within a Biosphere Reserve

The objective of this study is to present an efficiency-perception impact assessment based upon the integration of fuzzy logic (FL) of the "Productive Reconversion" conservation program (PRP) instituted by the Mexican government, in the upper Gulf of California and the Colorado Delta Biosphere Reserve. This approach enables environmental analysts to deal with the intrinsic imprecision and ambiguity associated with people's judgments and conclusions. The application of FL to the assessment of program efficiency is illustrated in this work, demonstrating how subjective perceptions can be converted into quantitative values easy to evaluate during the decision-making process.     

Poly(lactic acid)-Based Composites Containing Natural Fillers: Thermal,Mechanical and Barrier Properties

Natural filler/poly(lactic acid)-Based composites have been prepared by melt blending in order to investigate the resulting thermal, mechanical, and oxygen permeability properties. To this aim, several wastes or by-products (namely, cellulose fibers, wood sawdust, hazelnut shells, flax fibers, corn cob and starch) have been used, ranging from 10 to 30 wt%. The presence of these fillers is responsible of a slight reduction of the polymer degradation temperature in nitrogen as well as of a significant increase of the storage modulus as a function of the filler content. The experimental data obtained by dynamic mechanical analysis have been mathematically fitted, employing three micromechanical models (namely, Voigt, Reuss and Halpin–Tsai). Furthermore, the presence of cellulose or starch has turned out to significantly reduce the polymer oxygen permeability. Finally, in order to fully assess the feasibility of such materials, an economic analysis has been carried out and discussed.     

Diurnal and seasonal variations of carbonyls and their effect on ozone concentrations in the atmosphere of Monterrey,Mexico

Few studies have been made regarding carbonyl concentrations in Monterrey, México. The Monterrey Metropolitan Area (MMA) has the third largest population in the country and has increasing pollution issues. The concentrations of 10 aldehydes and two ketones were measured in the MMA, in the spring and fall of 2011 and 2012. Formaldehyde (16–42 ppbv) was the most abundant carbonyl, followed by acetaldehyde (5–15 ppbv) and acetone (7–15 ppbv). The concentrations showed marked diurnal trends with maximum values between 10:00 a.m. and 2:00 p.m., when photochemical activity is intense. Thus, secondary production of carbonyls is statistically significant in the city. Biogenic production of several carbonyls, such as 2-butanone, was supported by their mid correlation with solar radiation and low correlation with propionaldehyde, which is mainly emitted by anthropogenic sources. The seasonal variability of the concentrations was observed in the first three samplings, with the highest levels reached in the fall. The rainy conditions during the fourth sampling did not allow comparison. Carbonyl–NOx–O₃ analysis was made. Results indicated a carbonyl-sensitive atmosphere, especially during the midday samplings of 10:00 a. m. to 2:00 p.m. and 2:00 p.m. and 6:00 p.m. because of the intense solar radiation during these periods.

Implications:?Monitoring of carbonyls in Monterrey, Mexico, was performed to quantify the pollutant concentration in the city’s atmosphere. Although primary emission is significantly important, the secondary production of the pollutants, along with ozone production being carbonyl sensitive, indicates that air pollution controls must address the direct sources and the precursors of the pollutants to achieve air quality.     

Dichloroacetic acid degradation employing hydrogen peroxide and UV radiation

The degradation reaction of dichloroacetic acid employing H(2)O(2) and UVC radiation (253.7nm) has been studied in a well mixed reactor operating inside a recycling system. It has been shown that in an aqueous solution no stable reaction intermediates are formed and, at every time during the reaction, two mols of hydrochloric acid are formed for every mol of dichloroacetic acid that is decomposed and, in the same way, there is a paired agreement between the calculated TOC concentration corresponding to the unaltered dichloroacetic acid and the experimental values measured in the solution. On this basis and classical references from the scientific literature for the H(2)O(2) photolysis, a complete reaction scheme, apt for reaction kinetics mathematical modeling and ulterior scale-up is proposed.     

Probability density function of non-reactive solute concentration in heterogeneous porous formations

Available models of solute transport in heterogeneous formations lack in providing complete characterization of the predicted concentration. This is a serious drawback especially in risk analysis where confidence intervals and probability of exceeding threshold values are required. Our contribution to fill this gap of knowledge is a probability distribution model for the local concentration of conservative tracers migrating in heterogeneous aquifers. Our model accounts for dilution, mechanical mixing within the sampling volume and spreading due to formation heterogeneity. It is developed by modeling local concentration dynamics with an Ito Stochastic Differential Equation (SDE) that under the hypothesis of statistical stationarity leads to the Beta probability distribution function (pdf) for the solute concentration. This model shows large flexibility in capturing the smoothing effect of the sampling volume and the associated reduction of the probability of exceeding large concentrations. Furthermore, it is fully characterized by the first two moments of the solute concentration, and these are the same pieces of information required for standard geostatistical techniques employing Normal or Log-Normal distributions. Additionally, we show that in the absence of pore-scale dispersion and for point concentrations the pdf model converges to the binary distribution of [Dagan, G., 1982. Stochastic modeling of groundwater flow by unconditional and conditional probabilities, 2, The solute transport. Water Resour. Res. 18 (4), 835-848.], while it approaches the Normal distribution for sampling volumes much larger than the characteristic scale of the aquifer heterogeneity. Furthermore, we demonstrate that the same model with the spatial moments replacing the statistical moments can be applied to estimate the proportion of the plume volume where solute concentrations are above or below critical thresholds. Application of this model to point and vertically averaged bromide concentrations from the first Cape Cod tracer test and to a set of numerical simulations confirms the above findings and for the first time it shows the superiority of the Beta model to both Normal and Log-Normal models in interpreting field data. Furthermore, we show that assuming a-priori that local concentrations are normally or log-normally distributed may result in a severe underestimate of the probability of exceeding large concentrations.     

Removal of famoxadone, fluquinconazole and trifloxystrobin residues in red wines: effects of clarification and filtration processes

The effects of six clarification agents [egg albumin, blood albumin, bentonite + gelatine, charcoal, polyvinylpolypyrrolidine (PVPP) and silica gel] on the removal of residues of three fungicides (famoxadone, fluquinconazole and trifloxystrobin) applied directly to a racked red wine, elaborated from Monastrell variety grapes from the D.O. Region of Jumilla (Murcia, Spain) were studied. The clarified wines were filtered with 0.45 microm nylon filters to determine the influence of this winemaking process in the disappearance of fungicide residues. Analytical determination of fluquinconazole and trifloxystrobin was performed by gas chromatography with electron captor detector (ECD), while that of famoxadone using an HPLC equipped with a diode array detector (DAD). Generally, trifloxystrobin is the fungicide that is the lowest persistent one in wines, except in the egg albumin study whereas, the most persistent one is fluquinconazole. The elimination depends on the nature of the active ingredient, though the water stability in the presence of light within it has more influence than the solubility and polarity of the product itself. The most effective clarifying agents were the charcoal and PVPP. The silica gel and bentonite plus gelatine were not enough to reduce considerably the residual contents in the wine clarified with them. In general terms, filtration is not an effective step in the elimination of wine residues. The greatest removal after filtration is obtained in wines clarified with egg albumine and bentonite plus gelatine, and the lowest in those clarified with PVPP.     

Impact of psychological risk factors on disaster rescue operations: the case of Italian volunteers

This paper reports on research into the characteristics of emergency rescue workers, with a focus on psychological distress. We present the results of a study of volunteers from the Italian national civil protection programme. A questionnaire was administered to 2,576 subjects from all over Italy. Most respondents were men, mostly unemployed, whose average level of education was higher than that among most Italian volunteers. Many were poorly endowed with basic skills, with large differences according to geography. Many expected to convert their volunteer activities into permanent jobs. Using this data, we employed a logistical regression model to analyse the risk of low, moderate and severe psychological distress symptoms, including anxiety and panic attacks, during rescue operations. The results indicate that some rescuers are particularly vulnerable to distress. The highest risk factors pertained to volunteers from southern Italy whose training is inadequate, who have little experience of emergency work and who play subordinate roles in small teams that lack psychological support services.