Liquid discharges from patients undergoing 131I treatments

This work discusses the production and management of liquid radioactive wastes as excretas from patients undergoing therapy procedures with (131)I radiopharmaceuticals in Spain. The activity in the sewage has been estimated with and without waste radioactive decay tanks. Two common therapy procedures have been considered, the thyroid cancer (4.14GBq administered per treatment), and the hyperthyroidism (414MBq administered per treatment). The calculations were based on measurements of external exposure around the 244 hyperthyroidism patients and 23 thyroid cancer patients. The estimated direct activity discharged to the sewage for two thyroid carcinomas and three hyperthyroidisms was 14.57GBq and 1.27GBq, respectively, per week; the annual doses received by the most exposed individual (sewage worker) were 164muSv and 13muSv, respectively. General equations to calculate the activity as a function of the number of patient treated each week were also obtained.     

Using Mediterranean shrubs for the phytoremediation of a soil impacted by pyritic wastes in Southern Spain: a field experiment

Re-vegetation is the main aim of ecological restoration projects, and in Mediterranean environments native plants are desirable to achieve successful restoration. In 1998, the burst of a tailings dam flooded the Guadiamar river valley downstream from Aznalcóllar (Southern Spain) with sludges that contained elevated concentrations of metals and metalloids, polluting soils and waters. A phytoremediation experiment to assess the potential use of native shrub species for the restoration of soils affected by the spillage was performed from 2005 to 2007, with soils divided into two groups: pH < 5 and pH > 5. Four native shrubs (Myrtus communis, Retama sphaerocarpa, Rosmarinus officinalis and Tamarix gallica) were planted and left to grow without intervention. Trace element concentrations in soils and plants, their extractability in soils, transfer factors and plant survival were used to identify the most-interesting species for phytoremediation. Total As was higher in soils with pH < 5. Ammonium sulphate-extractable zinc, copper, cadmium and aluminium concentrations were higher in very-acid soils, but arsenic was extracted more efficiently when soil pH was >5. Unlike As, which was either fixed by Fe oxides or retained as sulphide, the extractable metals showed significant relationships with the corresponding total soil metal concentration and inverse relationships with soil pH. T. gallica, R. officinalis and R. sphaerocarpa survived better in soils with pH > 5, while M. communis had better survival at pH < 5. R. sphaerocarpa showed the highest survival (30%) in all soils. Trace element transfer from soil to harvestable parts was low for all species and elements, and some species may have been able to decrease trace element availability in the soil. Our results suggest that R. sphaerocarpa is an adequate plant species for phytostabilising these soils, although more research is needed to address the self-sustainability of this remediation technique and the associated environmental changes.     

Dioxin mass balance in a municipal waste incinerator

A dioxin mass balance in an Spanish municipal waste incinerator (MWI) is presented. Input and output inventories from two sampling collection episodes including the analysis of PCDD/PCDF in urban solid waste (USW), stack gas emissions, fly ash and slag are reported. In one collection the levels of USW were around 8 pg I-TEQ/g and non-thermal destruction was observed overall. In the other collection the levels of USW were higher (around 64 pg I-TEQ/g) and the dioxin balance revealed a thermal destruction. Analysis of the different waste materials (textile, organic, plastic, wood and paper) was performed separately and the textile samples presented the highest levels.     

The role of root organic acids in the tolerance of Festuca rubra to zinc,lead and cadmium

Abstract

Festuca rubra L. plants are pseudometallophytes colonizing abandoned Pb/Zn mine areas, successfully employed in phytostabilization. To study the contribution of low-molecular weight organic acids to metal tolerance, F. rubra plants were grown for three months in hydroponics with Cd (1.8, 18 and 36 µmol?L^?1), Pb (50, 250 and 500?µmol?L^?1) and Zn (0.3, 3 and 6?mmol?L^?1), separately, and in ternary combination (18?µmol?L^?1 Cd + 250?µmol?L^?1 Pb + 0.3?mmol?L^?1 Zn). The roots retained most of the metals but their distribution from shoot to root was altered when the plants were treated with the ternary combination. The main organic acids in roots were citrate and malate. At the lowest concentrations, the metals caused small reductions in biomass, had no effects on photosynthetic pigments nor on malondialdehyde, but led to increases in root organic acids. At higher concentrations, phytotoxic responses were observed, associated with a decline of citrate and malate in the roots.     

Community-based adaptation in low-lying islands in the Philippines: challenges and lessons learned

Community-based adaptation (CBA) seeks to address climate risks and socio-economic drivers of vulnerability simultaneously. However, as CBA activities appear very similar to standard development work, difficulties in identifying good practices arise. To clarify the role of CBA, this study elucidated how climate change can impact pre-existing development problems by investigating the experiences of four low-lying island communities in central Philippines. The islands currently suffer from frequent and extreme tidal flooding (following an earthquake-induced land subsidence in 2013, with a magnitude that is broadly similar to sea-level rise projections under a 1.5 to 2 °C global warming scenario), and endured a dry spell in 2016. The study also identified various publicly and privately initiated adaptation strategies, and evaluated their resilience against actual biophysical events. The study conducted focus group discussions with local leaders and in-depth interviews with government officials and residents in March 2016. Results show that tidal flooding impacted almost all aspects of daily life on the islands, while the dry spell completely depleted their limited water supplies. The strategies implemented by governments and NGOs (e.g., seawalls, rainwater collectors) were found to be inadequate in preventing tidal flooding and compensating for the dry spell. Also, communities used coral stones and plastic waste for raising the floors of their homes, which have an erosive effect on their capacity to adapt in the long term. Lack of community participation in publicly initiated projects and lack of adaptation funding for community-based strategies were the greatest obstacles to implementing climate-resilient solutions.     

Anatomical and ultrastructural studies of chemical defence in the sponge Dysidea fragilis

The marine sponge Dysidea fragilis from El Mar Menor, a hypersaline coastal lagoon (Murcia, Spain), contains the furanosesquiterpenoid ent-furodysinin as the major secondary metabolite. D. fragilis emits a defensive white fluid when it is disturbed. Electron micrographs of this fluid revealed intact vesiculated cells together with other amorphous material. Dissociated cells are more rounded in shape but maintain the same ultrastructural features as cells observed in ultra-thin sections of the whole sponge. The defensive secretion is composed mainly of sponge cells with abundant light vesicles. Sometimes these light vesicles appear to open into the intercellular space; this correlates with surface blebs on these cells observed under scanning electron microscopy. The intracellular location of ent-furodysinin was confirmed by Erlich staining. In laboratory assays, we examined the role of ent-furodysinin as a feeding deterrent to generalist fish predators. It was isolated from D. fragilis and incorporated into a carrageenan-based artificial diet. The addition of ent-furodysinin to the artificial diet reduced feeding by the fish Thalassoma pavo. Similarly, fish did not feed on artificial diet above which defensive secretion of D. fragilis had been ejected with a small syringe. Received: 4 June 1997 / Accepted: 28 January 1998     

Surveillance programme on dioxin levels in soils in the Campo de Gibraltar (southwest Spain)

The results of an epidemiologic study undertaken by the Spanish Council for Scientific Research (CSIC) after commission by the Spanish Parliament indicated that Huelva and Cádiz were the zones in Andalusia with elevated risk of cancer. A 6% (women) and 10% (men) cancer mortality excess was observed with respect to the other six Andalusian provinces. Huelva and Cádiz are located in the south-western region of Spain, and are characterized by a strong industrial activity concentrated in several industrial sites. This situation led to two environmental surveys in these areas, in which the presence of dioxins was studied among other parameters. A PCDD/F assessment in soils of the Campo de Gibraltar (Cádiz) was carried out from June 2003 to June 2004. A total of 20 samples were collected in this study divided in two sampling campaigns. The first 10 samples were taken in locations affected by high industrial activity zones as well as in landfills (hotspots). The rest of the samples were collected in areas that were not expected to be contaminated, such as agricultural zones and forests. I-TEQ values of the samples ranged from 0.26 to 15.08 ng/kg dm. In all, 85% of the samples were below the limit of 5 ng I-TEQ/kg I-TEQ concentrations of three samples only surpassed this limit. These zones corresponded to a landfill, a quarry used for dumping chemical product containers and a sample from the sewage system of the industrial site. These sites were used neither for agricultural nor for public purposes.     

Dioxin like compounds from municipal waste incinerator emissions: assessment of the presence of polychlorinated naphthalenes

Polychloronaphthalenes (PCN) were identified and quantified in emission samples collected from five different municipal waste incinerators (MWI). Polychlorodibenzo-p-dioxins (PCDD) and polychlorodibenzofurans (PCDF) were also determined to find a possible relationship between these classes of organochlorinated compounds. The analyses of PCDD/PCDF and PCN were carried out by high resolution gas chromatography coupled with high resolution mass spectrometry using a positive electron ionization source and operating in the selected ion monitoring analyzer mode (HRGC-HRMS/EI(+)-SIM). The total levels of PCN varied from 1.08 up to 21.36 ng/Nm3 (mono- to octachlorinated) and 0.33 to 5.72 ng/Nm3 (tetra- to octachlorinated), whereas the levels of PCDD/PCDF ranged between 1.14 and 276.26 ng/Nm3 (0.01 and 5 ng I-TEQ/Nm3), depending on the type of the MWI. These findings do not corroborate a PCN and PCDD/PCDF correlation.     

Ostracoda and foraminifera as short-term tracers of environmental changes in very polluted areas: the Odiel Estuary (SW Spain)

The analysis of 17 cores collected in the Odiel Estuary (SW Spain) permits delimiting the recent evolution of this zone during the past decades and the influence of natural and anthropogenic factors on the distribution of Ostracoda and Foraminifera. In the upper estuary, the coincidence of acid waters, prolonged subaerial exposure, and coarse sediments may explain the absence or the disappearance of these microorganisms during the industrial period (1966-1985) in the major part of this area. In the lower estuary, sedimentary evolution and industrial wastes are the main factors influencing both the distribution and trends of the populations of these two groups. Finally, the main changes observed in the marine estuary are due to the sedimentary effects of the construction of two banks and the dredging of the main estuarine channel.     

Removal of atrazine and four organophosphorus pesticides from environmental waters by diatomaceous earth-remediation method

A new viable remediation technique based on the use of diatomaceous earth is proposed to improve the ecological system. Its ability to remove atrazine and the four organophosphorus pesticides parathion-methyl, chlorpyriphos, fenamiphos and methidathion from river and waste waters has been proven. A series of experiments including variable conditions, such as temperature, pH, contact time, pesticide concentration and adsorbent quantity, were performed to demonstrate the efficiency of pesticide removal from three different water samples. The batch experiments showed that diatomaceous earth was able to remove 95% of chlorpyriphos, 75% of methidathion and parathion-methyl and 55% of atrazine and fenamiphos from all types of waters tested. The individual adsorption of each pesticide on diatomaceous earth could be described by the Freundlich isotherm and a tentative adsorption mechanism was proposed. The Freundlich coefficient (Kf) and Freundlich constant (1/n) appeared to be closely related to the physicochemical properties (Kow, solubility) of the compounds. The actual results support the conclusion that diatomaceous earth has the potential to serve as an extractant in remediation techniques.