Leptocephalus energetics: assembly of the energetics equation

The principles of energetics were used to examine the energetic requirements of leptocephali. Respiration and excretion rates and daily growth rates combined with proximate composition were used to examine the allocation of energy into each of the three main components of energetics: metabolism, excretion and growth. The daily energetic requirements for leptocephali, referred to as type 2 larvae based upon their unique developmental strategy, were compared to the requirements of non-leptocephalus larvae, known as type 1. Leptocephalus daily energetic requirements were also compared to the energy available from the leptocephalus' proposed food sources. The four species of eel larvae selected were all from the order Anguilliformes: Paraconger caudilimbatus (Poey), Ariosoma balearicum (Delaroche), Gymnothorax saxicola Jordan and Davis, and Ophichthus gomesii (Castelnau). The allocation of energy to each of the components of energetics as well as the total energetic requirements for the leptocephali proved to be very different from those of type 1 larvae. Metabolism received the majority, 60-92%, of the energy required per day. Growth and excretion were allocated 4-39% and <1-21%, respectively, of the total energy needed per day. Leptocephali required <50% of the energy needed by type 1 larvae of equal dry mass. The unique growth strategy used by leptocephali allows them to increase rapidly in size while allocating the majority of their energy, not to growth as in most larval fish, but to metabolism.     

Environmental sustainability and the integration of different methods for its assessment

The aim of this paper is to propose a research framework, based on the joint use of three widely used methods: EMergy Evaluation (EME), Ecological Footprint Analysis (EFA) and Greenhouse Gas Inventory (GHGI), that are applied to assess the environmental sustainability of a region. The results of application of these methods to several Italian Provinces enabled us to compare their sustainability, and to test the methods with respect to sustainability requirements at local and global level. The outcomes suggest that the proposed framework provides an organic evaluation of regional systems based on key aspects, such as resources depletion, consumption patterns, waste production and absorption.     

Evaluation of a portable nephelometer against the Tapered Element Oscillating Microbalance method for monitoring PM(2.5)

Monitoring personal exposure to particle matter (PM(2.5)) in ambient air requires performing measurements using portable monitors. In this work, the portable nephelometer SidePak? AM510 Personal Aerosol Monitor manufactured by TSI Inc. was evaluated against a Tapered Element Oscillating Microbalance (TEOM) equipped with a Filter Dynamics Measurements System (FDMS). Conventionally, the SidePak is calibrated with respect to the Arizona Road Test Dust and then multiplied by an environmental calibration factor to yield mass concentration. To adapt this calibration to specific field conditions, we present an implementation of this calibration by introducing a growing factor correction which takes into account relative humidity and the dry and wet portions of the refractive index estimated from TEOM-FDMS measurements. PM(2.5) sampling with several SidePaks AM510 was carried out in background and rural sites in the Po Valley (Italy). Modeled SidePak data were plotted vs. reference TEOM-FDMS data which show a good agreement.     

Detection of hormones in surface and drinking water in Brazil by LC-ESI-MS/MS and ecotoxicological assessment with <Emphasis Type="Italic">Daphnia magna</Emphasis>

The growing use of pharmaceutical drug is mainly due to several diseases in human and in animal husbandry. As these drugs are discharged into waterways via wastewater, they cause a major impact on the environment. Many of these drugs are hormones; in which even at low concentrations can alter metabolic and physiological functions in many organisms. Hormones were found in surface water, groundwater, soil, and sediment at concentrations from nanograms to milligrams per liter of volume—quantities known to cause changes in the endocrine system of aquatic organisms. This study aimed to develop a methodology for hormone detection (estriol, estrone, 17β-estradiol, 17α-ethinylestradiol, progesterone, and testosterone) on surface and treated water samples. Sample toxicity was assessed by ecotoxicology tests using Daphnia magna. A liquid chromatograph coupled to a mass spectrometer with an electrospray ionization source (LC-ESI-MS/MS) was used for the analysis. The results showed that samples were contaminated by the hormones estriol, estrone, progesterone, 17β-estradiol, and 17α-ethinylestradiol during the sampling period, and the highest concentrations measured were 90, 28, 26, 137, and 194 ng·L^?1, respectively. This indicates the inflow of sewage containing these hormones at some points in the Piracicaba River in the State of Sao Paulo—Brazil. Results indicated little toxicity of the hormone estriol in D. magna, indicating that chronic studies with this microcrustacean are necessary.     

Estimate of the uncertainty in measurement for the determination of mercury in seafood by TDA AAS

An approach for the estimate of the uncertainty in measurement considering the individual sources related to the different steps of the method under evaluation as well as the uncertainties estimated from the validation data for the determination of mercury in seafood by using thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) is proposed. The considered method has been fully optimized and validated in an official laboratory of the Ministry of Agriculture, Livestock and Food Supply of Brazil, in order to comply with national and international food regulations and quality assurance. The referred method has been accredited under the ISO/IEC 17025 norm since 2010. The approach of the present work in order to reach the aim of estimating of the uncertainty in measurement was based on six sources of uncertainty for mercury determination in seafood by TDA AAS, following the validation process, which were: Linear least square regression, Repeatability, Intermediate precision, Correction factor of the analytical curve, Sample mass, and Standard reference solution. Those that most influenced the uncertainty in measurement were sample weight, repeatability, intermediate precision and calibration curve. The obtained result for the estimate of uncertainty in measurement in the present work reached a value of 13.39%, which complies with the European Regulation EC 836/2011. This figure represents a very realistic estimate of the routine conditions, since it fairly encompasses the dispersion obtained from the value attributed to the sample and the value measured by the laboratory analysts. From this outcome, it is possible to infer that the validation data (based on calibration curve, recovery and precision), together with the variation on sample mass, can offer a proper estimate of uncertainty in measurement.     

Integrating methods for the environmental sustainability: the SPIn-Eco Project in the Province of Siena (Italy)

This paper shows how different methods can be integrated in order to provide an organic evaluation of the environmental sustainability at the territorial level. A territory is a complex, dynamic and open system where a population develops, uses resources, produces goods and services, consumes, depletes and finally obtains economic results. All these elements characterise human behaviour, which can be monitored, measured and compared to the capacity of the environment to sustain it in the long run. The SPIn-Eco Project for the Province of Siena (Italy) is described as an example of an environmental sustainability assessment of an area, and its methods (Ecological Footprint, Greenhouse Gas Inventory, Extended Exergy Analysis, Emergy Evaluation, Life Cycle Assessment (LCA) and Remote Sensing) are briefly introduced. This Project has been proposed and funded by the most important provincial administrative and financial institutions in the territory (the Administration of the Province of Siena and the Monte dei Paschi Foundation, respectively), and was designed and realised in 4 years (2001-2004) by a research team coordinated by the University of Siena.     

Can Pickering emulsion formation aid the removal of creosote DNAPL from porous media?

The purpose of this investigation was to examine the proposition that creosote, emplaced in an initially water saturated porous system, can be removed from the system through Pickering emulsion formation. Pickering emulsions are dispersions of two immiscible fluids in which coalescence of the dispersed phase droplets is hindered by the presence of colloidal particles adsorbed at the interface between the two immiscible fluid phases. Particle trapping is strongly favoured when the wetting properties of the particles are intermediate between strong water wetting and strong oil wetting. In this investigation the necessary chemical conditions for the formation of physically stable creosote-in-water emulsions protected against coalescence by bentonite particles were examined. It was established that physically stable emulsions could be formed through the judicious addition of small amounts of sodium chloride and the surfactant cetyl-trimethylammonium bromide. The stability of the emulsions was initially established by visual inspection. However, experimental determinations of emulsion stability were also undertaken by use of oscillatory rheology. Measurements of the elastic and viscous responses to shear indicated that physically stable emulsions were obtained when the viscoelastic systems showed a predominantly elastic response to shearing. Once the conditions were established for the formation of physically stable emulsions a "proof-of-concept" chromatographic experiment was carried out which showed that creosote could be successfully removed from a saturated model porous system.     

Persistent organic pollutants in atmospheric deposition and biomonitoring with Tillandsia Usneoides (L.) in an industrialized area in Rio de Janeiro state, south east Brazil--Part I: PCDD and PCDF

Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic Bromeliad species as biomonitor and measuring total deposition rates on funnels covered with polyurethane foams. Samples were collected during 78 days in V.R. and 95 days in PNI in winter (dry season, June-August 2003) and during 114 days in both areas in summer (rainy season, December 2003-February 2004). The PCDD/PCDF deposition rates ranged from 0.10 to 1.9 pg WHO-TEQ/(m2 day) in winter and from 0.11 to 2.2 pg WHO-TEQ/(m2 day) in summer. Deposition rates found in V.R. in summer were four- to ninefold higher than those measured in PNI, while in winter deposition rates in both regions were in the same range. Deposition rates in V.R. in summer were about five fold lower than those measured in 1996. PCDD/PCDF levels in biomonitor samples were between 0.95 and 14.6 ng WHO-TEQ/kg d.m. in winter and between 2.2 and 5.2 ng WHO-TEQ/kg d.m. in summer. In winter, concentrations found in V.R. were up to 11 times higher than those found in PNI, while in summer the levels measured in both areas were comparable. The homologue and isomer profiles found in the deposition as well as in the biomonitor samples from V.R. indicate that steel production is the main source of contamination in the region, whereas in PNI, the long range transport of these pollutants is the predominant contamination pathway.     

Sub-soil contamination due to oil spills in six oil-pipeline pumping stations in northern Mexico

Mexico has a very important oil industry, comprehending the exploration, production, transformation, storage and distribution of crude oil and its fractions. Petroleos Mexicanos (PEMEX) is a state-owned monopoly in charge of these activities. Oil and oil-products transport is an extremely crucial operation for the cycle production-transformation-distribution. Pipeline system transport crude oil and sub-products along the country (including liquids, gases and mixtures). It has been reported that more than 30% of the oil ducts in Mexico have been operating for over 30 years, although their lifetime has been calculated in 25-30 years. This work is aimed at characterizing a zone around six oil-pipeline pumping stations located at northern Mexico. The specific places to evaluate soil contamination were (1) the distribution head of the Gomez Palacio (GOPA) pumping station; (2) the north side of the old ditch, the API oil separator and the wastewater zones of the Jimenez (JIM) pumping station; (3) the pumping stations of Ceballos (CE), Peronal (PER), Simon Bolivar (SIBO), and Mayran (MAY). The study comprehended sampling of the areas, delimitation of contamination in the vertical and horizontal extension, analysis of the sampled soils, regarding TPH and, in some cases, the 16 PAHs considered as a priority by USEPA, calculation of areas and volumes contaminated (according to the Mexican legislation, specifically NOM-EM-138-ECOL-2002) and, finally, a proposal for the best remediation techniques suitable for the encountered contamination levels and the localization of contaminants. In general, TPHs were found in all the pumping stations analyzed in this study. Regarding maximal TPHs concentrations at the stations, their order of contamination was as follows: SIBO>CE>PER>MAY>JIM>GOPA. PAHs were found only in a few points at concentrations above the detection limit. At the Jimenez, Gomez Palacio, Peronal, and Ceballos stations, only one point, with PAHs values over the detection limit was found, whereas two points were found at Mayran, and finally at the Simon Bolivar station there were four points with measurable amounts of PAHs. Given the areas and volumes that need to be treated (32835 m3), as well as the physical position of contaminants, it is considered that excavation of the contaminated soil is feasible and the cleaning process could be soil washing assisted with surfactants, though bioremediation should not been discharged as a possible remediation technique.     

Radionuclide and chemical concentrations in mineral waters at Saratoga Springs, New York

A project to characterize the radionuclide and chemical components in natural spring waters in the vicinity of Saratoga Springs, New York (USA) has been completed. As a result of the measured radionuclide and chemical content, eight springs were labeled as mineral waters, whereas three springs contained very low concentrations of these components. The mineral waters were highly enriched in alkaline and alkaline-earth elements, as well as chloride ions. Three isotopes of radium ((224)Ra, (226)Ra, (228)Ra) were detected in the mineral waters and reached concentrations of 1, 20, and 2 Bq/L, respectively. Overall, the (226)Ra isotope constituted about 80% of the total radioactivity measured in the water samples. Dissolved uranium concentrations in the mineral waters were very low (mean approximately 50 mBq/L).