An integrated approach using bioaccumulation and biomarker measurements in female shore crab, Carcinus maenas

The shore crab Carcinus maenas, was used as a biomonitoring organism to measure the potential impact that the mining spill in the Guadalquivir Estuary (SW, Spain), in 1998 may have exerted on local biota. Female intermoult C. maenas were exposed to dissolved cadmium, copper and zinc at concentrations found in local waters following the spill (3 microgl-1 Cd, 15 microgl-1 Cu, 700 microgl-1 Zn). Groups of shore crabs were exposed for 21 days to these metals, both singularly and in combination. Residues of metals were measured in gill, midgut gland and muscle tissues, together with metallothioneins in the midgut gland, at the end of the exposure period. Haemolymph samples were taken every seven days, and vitellogenin/vitellin analysed to determine the flux of these compounds. Biomarker results suggested that they would be good indicators of the effects of heavy metal environmental contamination, particularly in the case of Cd and Zn. Variation in results was obtained between responses measured in crabs exposed to single metals and those exposed to combinations of metals.     

Chlorinated herbicide (triallate) dehalogenation by iron powder

The reductive degradation of a chlorinated herbicide by iron powder was investigated at lab scale. The studied substrate was triallate (S-2,3,3-trichloroallyl di-isopropyl thiocarbamate) which contains a trichloroethylene moiety potentially reducible by zero-valent iron. Degradation reactions were carried out in batch, at 25 degrees C, in the absence of oxygen, by contacting electrolytic iron powder (size range: 20-50 microm) with a triallate aqueous solution (2.5 mgl(-1)). Herbicide decay, corresponding evolutions of TOC, TOX and chloride ion release were regularly monitored throughout the reactions. Furthermore, the main degradation by-products were identified by HPLC/MS. The results showed that, after 5 days, herbicide degradation extent was about 97% and that the reaction proceeded through the formation of a dechlorinated alkyne by-product (S-2-propinyl di-isopropyl thiocarbamate) resulting from the complete dechlorination of triallate. The subsequent reduction of such an alkyne intermediate gave S-allyl di-isopropyl thiocarbamate as main end by-product. The identified by-products suggested that dechlorination took place mainly via reductive beta-elimination. However, as traces of dichloroallyl di-isopropyl thiocarbamate were also detected, a role, although minor, was assigned even to hydrogenolysis in the overall dechlorination process.     

Effect of lanthanum loading on nanosized CeO2-ZnO solid catalysts supported on cordierite for diesel soot oxidation

We report the application of a solid lanthanum–ceria–zinc catalyst in the catalytic regeneration of diesel particulate filters(DPF) in diesel engines.We synthesized a CeO_2–ZnO–La_2O_3(Ce–Zn–La) mixed oxide by a lactic acid-mediated sol–gel method,which efficiently coated cordierite substrates for soot capture and combustion.We studied the effects of La loading on the physicochemical and catalytic properties of Ce–Zn mixed oxide during lowtemperature soot combustion processes.We characterized the synthesized catalysts by X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),N2 adsorption,Raman spectroscopy,oxygen storage capacity(OSC),and scanning and transmission electron microscopy(SEM and TEM).Thermogravimetric and differential thermal analysis(TGA/DTA)confirmed that the catalysts effectively reduced the soot oxidation temperature.The ternary Ce–Zn–La mixed oxide catalyst with Ce/Zn/La atomic ratio of 2:1:0.5 had the highest catalytic activity and promoted soot oxidation at temperatures below 390°C.This indicated that the large number of oxygen vacancies in the catalyst structure generated oxygen species at low temperatures.Raman spectroscopy measurements revealed the presence of oxygen vacancies and lattice defects in Ce–Zn–La samples,which were key parameters concerning the stability and redox properties of the prepared catalysts.     

Large-Scale Survey of Human Enteroviruses in Wastewater Treatment Plants of a Metropolitan Area of Southern Italy

Human enteroviruses (HEVs) occur in high concentrations in wastewater and can contaminate receiving environmental waters, constituting a major cause of acute waterborne disease worldwide. In this study, we investigated the relative abundance, occurrence, and seasonal distribution of polio and other enteroviruses at three wastewater treatment plants (WWTPs) in Naples, Southern Italy, from January 2010 to December 2014. Influent and effluent samples from the three WWTPs were collected monthly. One hundred and sixty-one of the 731 wastewater samples collected (22.0%) before and after water treatment were CPE positive on RD cells; while no samples were positive on L20B cells from any WWTPs. Among the 140 non-polio enterovirus isolated from inlet sewage, 69.3% were Coxsackieviruses type B and 30.7% were Echoviruses. Among these, CVB3 and CVB5 were most prevalent, followed by CVB4 and Echo6. The twenty-one samples tested after treatment contained 6 CVB4, 5 CVB3, 3 Echo11, and 2 Echo6; while other serotypes were isolated less frequently. Data on viral detection in treated effluents of WWTPs confirmed the potential environmental contamination by HEVs and could be useful to establish standards for policies on wastewater management.     

Environmental monitoring within the Slovak Republic

In the Slovak Republic (SR) there has not been a complete and coordinated monitoring system for environment until now. The object of environmental monitoring in the SR has been to evaluate certain areas, e.g. components of the environment and the influences affecting it: atmosphere, water, soil, biota (fauna and flora), geological factors, physical fields, forest, wastes, settlement, landuse, contaminants of the food chain and human stress caused by environmental factors. Individual monitoring systems are being built on the basis of these projects.The Monitoring System for the Environment in the SR has been formed by linkage to the Information System on the Environment in the SR which is a basic source of the data on the state of the environment in the SR and the factors affecting it.The guarantor of both these systems is the Ministry of the Environment of the Slovak Republic.     

Distribution of Heavy Metals in Surface Sediments from an Antarctic Marine Ecosystem

The concentrations of lead, cadmium, copper,chromium, iron, manganese and zinc in surfacesediments collected from Potter Cove, in the 25de Mayo Island (King George Island), Antarctica, andits drainage basin, were measured by atomic absorptionspectroscopy. The obtained results were use todetermine the areal and vertical distribution of themetals of in the Cove and potential sources of thesemetals to this environment. The geochemical datasuggest that most of the metals found in Potter Coveconstitute a redistribution of autochthonous materialswithin the ecosystem. Therefore, the metalconcentrations can be considered to be present atnatural background levels in surface sediments.     

Distribution and speciation of metals in annual rings of black willow

Information on the spatial distribution and speciation of metals in nonhyperaccumulator plants is lacking. This study used synchrotron X-ray fluorescence (SXRF) compositional imaging to investigate the spatial distribution of Ni, Mn, Cu, Zn, and Fe in annual rings of black willow (Salix nigra L.) collected from a metal-contaminated area, and used X-ray absorption spectroscopy (XAS) to investigate Ni and Mn speciation in regions of the annual rings with elevated Ni concentrations. Annual rings were recollected in early 2003 from an individual known to be enriched with Ni from previous studies. Compositional imaging showed Ni and associated co-contaminants conservatively located in an annual ring. When compared with a corresponding photomicrograph, SXRF compositional images showed that metals were sharply constrained by the boundaries of the annual ring, indicating a sudden onset and cessation of uptake, and a lack of post-growth mobility of the metals. There was a particularly strong correlation between Ni and Mn in the metal-enriched annual ring (r = 0.8822), which suggested similar transport and binding behavior of these elements. X-ray absorption spectroscopy showed Ni and Mn to be present in the 2+ oxidation state. X-ray absorption near edge structure spectroscopy (XANES) fingerprinting of localized, highly Ni-enriched regions within the lumen of willow xylem vessels found similarities with Ni-pectic acid complexes, Ni-histidine, and NiSO4.     

MODELING THE PERFORMANCE OF DEEP WASTE STABILIZATION PONDS1

ABSTRACT: The performance characteristics of a deep waste stabilization pond operating in Southeast Spain were studied for one year; the results show a high reduction in organic load and nutrients, as well as disinfection of the effluent, after a retention time that varies as a function of climatic conditions. Mathematical models describing its hydraulic, thermal, and biochemical bahavior are presented and compared with a set of measured data.     

Transplacental amniocentesis: Is it really a higher-risk procedure?

The aim of this study was to compare transplacental with non-transplacental amniocentesis in terms of related complications. Between January 1991 and December 1992, 4564 genetic amniocenteses were performed in 4527 patients (4491 singleton, 35 twin, and one triplet pregnancy) at 15–16 weeks of gestation. All the procedures were ultrasound-guided and performed by the same operator. In 1487 cases, an anterior placenta was traversed with the needle, whereas in 3077 cases, the needle was inserted directly into the amniotic cavity without traversing the placenta. After the exclusion of patients in whom amniotic cell culture failed or in whom an abnormal karyotype was obtained, and of patients lost to follow-up, a total of 4454 patients (98 per cent) were followed for 30 days after amniocentesis. Two spontaneous abortions occurred after a transplacental procedure, and five after a non-transplacental procedure (P = not significant). There were no episodes of amniotic fluid leakage in the first group, whereas 16 ruptures of the membranes that resolved spontaneously occurred in the second group (P<0·01). Our data suggest that transplacental amniocentesis carries a similar abortive risk to and a lower risk of transient rupture of the membranes than non-transplacental amniocentesis and may therefore be preferred at the gestational period examined (15–16 weeks). However, the risk of feto-maternal haemorrhage, which is reported to be higher for a transplacental procedure, must be considered in the case of an anterior placenta.     

Umbilical artery velocity waveforms before and after chorionic villus sampling

Because a vascular aetiology has been suggested for the limb and oromandibular defects described after chorionic villus sampling (CVS), to determine whether transabdominal (TA) CVS causes noticeable changes in umbilical artery velocity waveforms in first-trimester pregnancies, the pulsatility index (PI) of the umbilical artery was evaluated before and after TA-CVS in 175 pregnancies sampled between 10·0 and 13·0 weeks' gestation. In 139 uncomplicated pregnancies, the mean PI values (with 95 per cent confidence interval) were before TA-CVS 2·751 (2·692–2·809), after 10 min 2·723 (2·697–2·809), and after 1 h 2·781 (2·722–2·840). There were no significant changes in PI relative to the CVS procedure either in pregnancies with an abnormal result or in those ending in spontaneous abortion. Our data do not support any statistically significant change in umbilical artery PI relative to TA-CVS in first-trimester pregnancies. This procedure, despite its invasive character, does not appear to affect the feto-placental circulation.