The quest for eco-social efficiency in biofuels production in Brazil

Equating eco-efficiency with the business link to sustainable development is clearly limited, especially with the new paradigms brought up by Corporate Social Responsibility, which has shown that the private sector’s contribution to sustainable development can go far beyond the sphere of pollution control. It is necessary to give eco-efficiency a broader meaning so that it can support the quest for sustainable development. This requires the inclusion of social aspects, leading to a kind of eco-social efficiency. The present paper illustrates this idea by comparing Brazilian production and use of ethanol from sugarcane, in the context of the National Alcohol Program (Proalcool), with biodiesel production and use, in the context of the Biodiesel National Program (PNPB). Despite the problems presented, PNPB was designed to encourage companies to align productivity concerns with social ones, what could be the beginning of the here called eco-social efficiency.     

Enhancement of source traceability of atmospheric PM by elemental chemical fractionation

During a 1-year study (“Fine dust” Project) funded by the Lazio regional government (Italy), about 1000 daily PM₁₀ and PM_2.5 samples collected from six sites in the region were subjected to chemical fractionation based on differences in elemental solubility. In this way, it was possible to achieve meaningful characterization of the elemental composition of individual samples. For most of the investigated elements, we found significant differences between the extracted and the mineralized residual fraction. In general, fine particulate was best characterized by the composition of the extracted fraction, while coarse particles from traffic-related sources were best characterized using residues. For several metals (Cd, Pb, Sn, Sb and V) having a critical environmental impact, this result was particularly clear.The application of Principal Component Analysis (PCA) and receptor modelling (PCR) to the data set allowed us to evidence the enhancement of selectivity towards different emission sources that is obtained when chemical fractionated data are considered instead of total element content. Chemical fractionation seems to generate very selective markers for specific emission sources and in particular for re-suspended road dusts, one of the main factors responsible for the increase of elemental concentrations in urban areas.     

Urban regeneration and democratization of information access: CitiStat experience in Baltimore

This article explores the potential of a GIS-based approach to city management - Baltimore's CitiStat e-government program - for meeting the goals of sustainable urban regeneration. The argument advocated here builds on the widely held recognition that the application of ICTs in general can lead to both new forms of inclusion and exclusion of citizens. Therefore attending to the 'digital divide' is a relevant issue because cities are complex environments where outcomes of interventions are uncertain and widening participative arenas to different actors can increase the possibilities to regenerate declining urban areas in a more democratic way.     

Occurrence of sulfonamide residues along the Ebro River basin: removal in wastewater treatment plants and environmental impact assessment

Sulfonamides (SAs) have become one of the antibiotic families most frequently found in all kind of environmental waters. In the present work, the presence of 16 SAs and one of their acetylated metabolites in different water matrices of the Ebro River basin has been evaluated during two different sampling campaigns carried out in 2007 and 2008. Influent and effluent samples from seven wastewater treatment plants (WWTPs), together with a total of 28 river water samples were analyzed by on-line solid phase extraction-liquid chromathography-tandem mass spectrometry (on-line SPE-LC-MS/MS). Sulfamethoxazole and sulfapyridine were the SAs most frequently detected in WWTPs (96-100%), showing also the highest concentrations, ranging from 27.2 ng L(-1) to 596 ng L(-1) for sulfamethoxazole and from 3.7 ng L(-1) to 227 ng L(-1) for sulfapyridine. Sulfamethoxazole was also the SA most frequently detected in surface waters (85% of the samples) at concentrations between 11 ng L(-1) and 112 ng L(-1). In order to assess the effectiveness of the wastewater treatment in degrading SAs, removal efficiencies in the seven WWTPs were calculated for each individual SA (ranging from 4% to 100%) and correlated to the corresponding hydraulic retention times or residence times of the SAs in the plants. SAs half-lives were also estimated, ranging from to 2.5 hours (sulfadimethoxine) to 128 h (sulfamethazine). The contribution of the WWTPs to the presence of SAs depends on both the load of SAs discharging on the surface water from the WWTP effluent but also on the flow of the receiving waters in the discharge sites and the dilution exerted; WWTP4 exerts the highest pressure on the receiving water course. Finally, the potential environmental risk posed by SAs was evaluated calculating the hazard quotients (HQ) to different non-target organisms in effluent and river water. The degree of susceptibility resulted in algae>daphnia>fish. Sulfamethoxazole was the only SA posing a risk to algae in effluent water, with an HQ>7.     

AMEG: the new SETAC advisory group on aquatic macrophyte ecotoxicology

Introduction and background

Primary producers play critical structural and functional roles in aquatic ecosystems; therefore, it is imperative that the potential risks of toxicants to aquatic plants are adequately assessed in the risk assessment of chemicals. The standard required macrophyte test species is the floating (non-sediment-rooted) duckweed Lemna spp. This macrophyte species might not be representative of all floating, rooted, emergent, and submerged macrophyte species because of differences in the duration and mode of exposure; sensitivity to the specific toxic mode of action of the chemical; and species-specific traits (e.g., duckweed's very short generation time).

Discussion and perspectives

These topics were addressed during the workshop entitled “Aquatic Macrophyte Risk Assessment for Pesticides” (AMRAP) where a risk assessment scheme for aquatic macrophytes was proposed. Four working groups evolved from this workshop and were charged with the task of developing Tier 1 and higher-tier aquatic macrophyte risk assessment procedures. Subsequently, a SETAC Advisory Group, the Macrophyte Ecotoxicology Group (AMEG) was formed as an umbrella organization for various macrophyte working groups. The purpose of AMEG is to provide scientifically based guidance in all aspects of aquatic macrophyte testing in the laboratory and field, including prospective as well as retrospective risk assessments for chemicals. As AMEG expands, it will begin to address new topics including bioremediation and sustainable management of aquatic macrophytes in the context of ecosystem services.     

Degradation of atrazine using solar driven fenton-like advanced oxidation processes

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) was degraded using cobalt-peroximonosulfate (Co/PMS) advanced oxidation process (AOP). Three Co concentrations (0.00, 0.25 and 0.50 mM) and five peroximonosulfate (PMS) concentrations (0, 5, 8, 16 and 32 mM) were tested. Maximum degradation reached was 88% using dark Co/PMS in 126 minutes when 0.25 mM of cobalt and 32 mM of PMS were used. Complete atrazine degradation was achieved when the samples were irradiated by the sun under the same experimental conditions described. Tests for identification of intermediate products allowed identification and quantification of deethylatrazine in both dark and radiated conditions. Kinetic data for both processes was calculated fitting a pseudo-first order reaction rate approach to the experimental data. Having kinetic parameters enabled comparison between both conditions. It was found that the kinetic approach describes data behavior appropriately (R2 > or = 0.95). Pseudo-kinetic constants determined for both Co/PMS processes, show k value of 10(-4) for Co/PMS and a k value of 10(-3) for Co/PMS/ultraviolet (UV). This means, that, with the same Co/PMS concentrations, UV light increases the reaction rate by around one order of magnitude than performing the reaction under dark conditions.     

Evaluation of a simultaneous sampling method of PAHs, PCDD/Fs and dl-PCBs in ambient air

The Stockholm Convention on Persistent Organic Pollutants (POPs) was signed in May 2001 by 127 countries. Currently, 12 substances are regulated by the convention, and the work on finding new candidate chemicals to the convention has started. Among these 12 substances, dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are the objects of this study. There are no European standard methods for the simultaneous determination of these microorganic compounds, together with polycyclic aromatic hydrocarbons (PAHs) in ambient air--they must be referred to three different methods developed by the U.S. Environmental Protection Agency (EPA). The quali-quantitative analysis of these microorganic pollutants is an important challenge due to the low concentrations at which they may be present. In this study, the development of a simplified, alternative, fast and affordable sampling method for the determination of PAHs, PCDDs, PCDFs and PCBs in ambient air was performed. The sampling time was extended from 24 h to 7 d in order to enrich the sample, to fall within the instrumental limits of detection and to reduce the number of samples to be processed and, therefore, errors that may arise. First of all, experiments with labelled standards were conducted in the research area of Montelibretti (rural station, which is sited about 20 km northeast of Rome), with the purpose of optimizing sampling efficiency. Finally, the method was applied to the analysis of these compounds in the air of a suburban area with small industrial plants in order to evaluate the feasibility of the proposed sampling method system, by comparing concentrations of native compounds acquired during simultaneous daily and weekly sampling.     

Environmental study of two significant solid samples: gravitation dust sediment and soil

In this work are presented results of the complex study of two significant solid environmental samples: gravitation dust sediments (industrial pollutants, potential source of risk elements input to soils) and soils (component of the environment, potential source of risk elements input to food web). The first phase of this study was focused on the study of the significant chemical properties (phase composition, content of organic and inorganic carbon) of the dust and soil samples. In the second phase, the fractionation analysis was used on the evaluation of the mobility of chosen risk elements (Cu, Ni, Pb, Zn) in the studied samples. The single-step extractions were applied in the order of the isolation of the element forms (fractions), with different mobilities during defined ecological conditions by utilization of the following reagents: 1 mol dm^− 3 NH₄NO₃ for isolation of the “mobile” fraction, 0.05 mol dm^− 3 ethylenediaminetetraacetic acid and 0.43 mol dm^− 3 CH₃COOH for isolation of the “mobilizable” fraction, and 2 mol dm^− 3 HNO₃ for isolation of all releasable forms. On the basis of the results obtained in this study, it is possible to state that different origins and positions of solid environmental samples in the environment reflect in different chemical properties of their matrix. The different properties of the sample matrix result in different mobilities of risk elements in these kinds of samples. The fractionation analysis with single-step extraction for isolation element fractions is the method most suitable for easy checking of environmental pollution and for evaluation of risk elements cycle in the environment.     

Identification of heavy metal sources by multivariable analysis in a typical Mediterranean city (SE Spain)

Problems associated with heavy metal characterization in the majority of sites are often due to multiple sources of pollution. This work presents the results through the use of advanced statistical techniques to identify sources of soil heavy metals in a typical Mediterranean city. The multivariable analysis performed on seven metals identified four sources controlling their variability. Cr, Mn, and Ni contents were associated to soil parent materials; Cd and Pb contents were related to anthropogenic activities, specifically industrial activities and traffic; Cu content is controlled by long-term application of inorganic fertilizers in agricultural areas. Finally, zinc concentration is associated to commercial and outdoor activities in the area. These results were supported by the fact that metals associated to parent material (Cr, Mn, and Ni) were better correlated with soil lithogenic properties, while anthropogenic metals were correlated with more variable soil constituents.