Mineralization of paracetamol in aqueous medium by anodic oxidation with a boron-doped diamond electrode

The degradation of 100ml of solutions with paracetamol (N-(4-hydroxyphenyl)acetamide) up to 1 g l(-1) in the pH range 2.0-12.0 has been studied by anodic oxidation in a cell with a boron-doped diamond (BDD) anode and a graphite cathode, both of 3-cm2 area, by applying a current of 100, 300 and 450 mA between 25 and 45 degrees C. Complete mineralization is always achieved due to the great concentration of hydroxyl radical (*OH) generated at the BDD surface, with release of NH4+ and NO3- ions. The mineralization rate is pH-independent, increases with increasing applied current and temperature, but decreases when drug concentration raises from 315 mg l(-1). Reversed-phase chromatography revealed a similar complex paracetamol decay in acid and alkaline media. Ion-exclusion chromatography allowed the detection of oxalic and oxamic acids as ultimate carboxylic acids. When the same solutions have been comparatively treated with a Pt anode, a quite poor mineralization is found because of the production of much lower *OH concentration. Under these conditions, the degradation rate is enhanced in alkaline medium and polymerization of intermediates is favored in concentrated solutions. Paracetamol can be completely destroyed with Pt and its kinetics follows a pseudo-first-order reaction with a constant rate independent of pH.     

Achievements, difficulties and future challenges for the FARMING network

The EC FARMING network (Food and Agriculture Restoration Management Involving Networked Groups) was set up to bring together the many and diverse stakeholders who would be involved in intervention following wide scale radioactive contamination of the food chain, so that acceptable strategies can be developed for maintaining agricultural production and safe food supply. The network comprises stakeholder panels in the UK, Finland, Belgium, France and Greece that have met regularly since 2001 to debate, discuss and exchange opinion on the acceptability, constraints and impact of various countermeasure options and strategies. The objectives of this paper are to consolidate the main achievements of the FARMING project over the period 2000-2004, to highlight the various difficulties that were encountered and to discuss the challenges for engaging stakeholders in off-site emergency management and long-term rehabilitation in the future.     

Application of a Physical Input–Output Table to Evaluate the Development and Sustainability of Continental Water Resources in Spain

Continental waters are complex resources in terms of a measurable physical quantity, and measuring them requires a good knowledge of total water availability. In this research, an accounting physical input–output table (PIOT) was applied to evaluate total water resources and gross annual availabilities at each stage of the natural-artificial water cycle. These stages are considered subsystems of a continental water resource system describing water transfers for an average year within 13 administrative basins of Spain. Water transfers between various subsystems are characterized by internal flows decreasing the water resource availabilities. The PIOT analysis establishes these internal flows, and the origins and final uses of the total resources for each subsystem. The input-output balance registered an unsustainable negative net accumulation in eight water basins. The PIOT analysis also allowed the calculation of significant indicators such as water resource developments (RDI) and their sustainable use (SUI). RDI and SUI demonstrate that groundwater is a critical resource affecting the environment (e.g., wetlands in the upper Guadiana) and the water supply (e.g., irrigation in the Segura basin). The results of this model suggest that above-/below-ground hydrological links are important when decisions have to be made in order to provide a satisfactory supply of water in Spain. The model integrates the different water basins under territorial criteria, and therefore it may be useful for the Spanish National Hydrological Plan.     

Predicted growth of world urban food waste and methane production.

Landfill gas emissions are one of the largest anthropogenic sources of methane especially because of food waste (FW). To prevent these emissions growing with world population, future FW best management practices need to be evaluated. The objective of this paper was therefore to predict FW production for 2025 if present management practices are maintained, and then, to compare the impact of scenario 1: encouraging people to stay in rural areas and composting 75% of their FW, and; of scenario 2, where in addition to scenario 1, composting or anaerobically digesting 75% of urban FW (UFW). A relationship was established between per capita gross domestic product (GDP) and the population percentage living in urban areas (%UP), as well as production of municipal solid waste (MSW) and UFW. With estimated GDP and population growth per country, %UP and production of MSW and UFW could be predicted for 2025. A relatively accurate (R(2) > 0.85) correlation was found between GDP and %UP, and between GDP and mass of MSW and FW produced. On a global scale, MSW and UFW productions were predicted to increase by 51 and 44%, respectively, from 2005 to 2025. During the same period, and because of its expected economic development, Asia was predicted to experience the largest increase in UFW production, of 278 to 416 Gkg. If present MSW management trends are maintained, landfilled UFW was predicted to increase world CH4 emissions from 34 to 48 Gkg and the landfill share of global anthropogenic emissions from 8 to 10%. In comparison with maintaining present FW management practices, scenario 1 can lower UFW production by 30% and maintain the landfill share of the global anthropogenic emissions at 8%. With scenario 2, the landfill share of global anthropogenic emissions could be further reduced from 8 to 6% and leachate production could be reduced by 40%.     

Semilobar holoprosencephaly in a 46,XY female fetus

We report the prenatal echographic diagnosis of holoprosencephaly (HPE) at 11 weeks' gestation. Fetopathological examination revealed an unusual variant of semilobar HPE with middle interhemispheric fusion associated with sex-reversal: 46,XY normal male karyotype, normal external and internal female genitalia and streak gonads. Copyright © 2001 John Wiley & Sons, Ltd.     

Effects of aeration on water quality from septic system leachfields

We conducted a pilot-scale study at a research facility in southeastern Connecticut to assess the effects of leachfield aeration on removal of nutrients and pathogens from septic system effluent. Treatments consisted of lysimeters periodically aerated to maintain a headspace O(2) concentration of 0.209 mol mol(-1) (AIR) or vented to an adjacent leachfield trench (LEACH) and were replicated three times. All lysimeters were dosed with effluent from a septic tank for 24 mo at a rate of 12 cm d(-1) and subsequently for 2 mo at 4 cm d(-1). LEACH lysimeters had developed a clogging mat, or biomat, 20 mo before the beginning of our study. The level of aeration in the AIR treatment was held constant regardless of loading rate. No conventional biomat developed in the AIR treatment, whereas a biomat was present in the LEACH lysimeters. The headspace of LEACH lysimeters was considerably depleted in O(2) and enriched in CH(4), CO(2), and H(2)S relative to AIR lysimeters. Drainage water from AIR lysimeters was saturated with O(2) and had significantly lower pH, five-day biological oxygen demand (BOD(5)), and ammonium, and higher levels of nitrate and sulfate than LEACH lysimeters regardless of dosing rate. By contrast, significantly lower levels of total N and fecal coliform bacteria were observed in AIR than in LEACH lysimeters only at the higher dosing rate. No significant differences in total P removal were observed. Our results suggest that aeration may improve the removal of nitrogen, BOD(5), and fecal coliforms in leachfield soil, even in the absence of a biomat.     

Health risk assessment of emissions of dioxins and furans from a municipal waste incinerator: comparison with other emission sources

The aim of this study was to calculate the incremental lifetime-risk to dioxins and furans (PCDD/Fs) for the population living in the surroundings of a municipal solid waste incinerator (MSWI), as well as to establish the potential reduction on human health risks as a consequence of the adaptation to the EU legislation on pollutant emissions from the MSWI stack. Analytical and modelled results were obtained. PCDD/F concentrations in environmental media were determined by means of a simple-compartment-multimedia model (air-soil-vegetation model). Predicted and measured PCDD/F concentrations in soils and vegetation were compared, and the effects of MSWI emissions in the environmental media were determined. Human health risks due to PCDD/F emissions from the MSWI were also estimated based on I-TEQ measured and modelled in various environmental media. Cancer risks due to PCDD/F emissions of the plant were 1.07E-07 and 3.08E-09, before and after installation of the clean air system, respectively. On the other hand, cancer risks due to other PCDD/F emission sources in the area were 5.54E-06 and 1.86E-06. Total PCDD/F cancer risks (including those from diet) for the population living in the vicinity of the MSWI were 1.3E-04 and 4.25E-05, respectively (67.6% of reduction). Hazard ratio for total PCDD/F exposure (including diet) decreased during the last 5 years from 1.16 to 0.38. The above data show that other emission sources of PCDD/Fs also have a notable environmental impact on the area under direct influence of the MSWI.     

Assessment of application-rate dependent effects of a long-term fire retardant chemical (Fire Trol 934) on Typha domingensis germination

Although long-term fire retardants (LTR) gain increasingly acceptance as effective tools for wildfire management, recent studies indicate their potential harmfulness in the environment, especially in aquatic ecosystems. This study comprises a first laboratory impact assessment of LTR action in temporal Mediterranean wetlands, using seed germination of Typha domingensis as indicator of impact. Our aim was to identify application rates upon which seed germination could be significantly affected. We tested for low (1 l m(-2)) and high (3 l m(-2)) application rates of Fire Trol 934 which are recommended by the manufacturers as a function of fuel characteristics. In addition, we simulated the impact of a higher application rate of 5 l m(-2) because inhomogeneous dispersal of the LTR during fire control and prevention operations can result in locally elevated applications. Results of a microcosm experiment indicate that application rates of 1 or 3 l m(-2) can impact Typha germination rates in the short-term via indirect LTR-mediated effects on water quality, which suppressed necessary cues for germination. However, a subsequent experiment with Petri dishes, using seeds isolated from the LTR treated sediments did not show significantly different germination rates between the control and the treatments with application rates of 1 or 3 l m(-2). This suggests that retardant pre-application germination success could be recovered in nature once the retardant is eliminated. By contrast, seeds almost completely failed to germinate in the microcosm experiment and the subsequent Petri dish essay when an application rate of 5 l m(-2) was used. This suggests a critical level upon which Typha seed germination may be perpetually limited. Research should be extended to other plant species to provide fire managers with guidelines for environmentally safe use of LTR in the Mediterranean region.