Development of a simple extraction cell with bi-directional continuous flow coupled on-line to ICP-MS for assessment of elemental associations in solid samples

A continuous-flow system comprising a novel, custom-built extraction module and hyphenated with inductively coupled plasma-mass spectrometric (ICP-MS) detection is proposed for assessing metal mobilities and geochemical associations in soil compartments as based on using the three step BCR (now the Measurements and Testing Programme of the European Commission) sequential extraction scheme. Employing a peristaltic pump as liquid driver, alternate directional flows of the extractants are used to overcome compression of the solid particles within the extraction unit to ensure a steady partitioning flow rate and thus to maintain constant operationally defined extraction conditions. The proposed flow set-up is proven to allow for trouble-free handling of soil samples up to 1 g and flow rates < or =10 mL min(-1). The miniaturized extraction system was coupled to ICP-MS through a flow injection interface in order to discretely introduce appropriate extract volumes to the detector at a given time and with a given dilution factor. The proposed hyphenated method demonstrates excellent performance for on-line monitoring of major and trace elements (Ca, Mn, Fe, Ni, Pb, Zn and Cd) released when applying the various extracting reagents as addressed in the BCR scheme, that is, 0.11 M CH(3)COOH, 0.1 NH(2)OH.HCl and 30% H(2)O(2), even when a well recognized matrix-sensitive detector, such as ICP-MS, is used. As a result of the enhanced temporal resolution of the ongoing extraction, insights into the breaking down of phases and into the kinetics of the metal release are obtained. With the simultaneous multielement detection capability of ICP-MS, the dynamic fractionation system presents itself as an efficient front-end for evaluation of actual elemental association by interelement comparison of metals leached concurrently during the extraction time. Thus, the intimate elemental association between Cd and Zn in contaminated soils could be assessed.     

Air concentrations of PCDD/Fs, PCBs and PCNs using active and passive air samplers

The concentrations of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) were determined in air samples collected at four sampling sites located in two zones of Barcelona (Spain): near a municipal solid waste incinerator (MSWI) and a combined cycle power plant (3 sites), and at a background/control site. Samples were collected using high-volume active samplers. Moreover, 4 PUF passive samplers were deployed at the same sampling points during three months. For PCDD/Fs, total WHO-TEQ values were 27.3 and 10.9 fg WHO-TEQm(-3) at the urban/industrial and the background sites, respectively. The sum of 7 PCB congeners and the Sigma PCN levels were also higher at the industrial site than at the background site. In order to compare active and passive sampling, the accumulated amounts of PCDD/Fs, PCBs and PCNs in the four passive air samplers, as well as the total toxic equivalents in each sampling site were also determined. To assess the use of PUF passive samplers as a complementary tool for PCDD/F, PCB and PCN monitoring, sampling rates were calculated in accordance with the theory of passive air samplers. PUF disks allowed establishing differences among zones for the POP levels, showing that they can be a suitable method to determine POP concentrations in air in areas with various potential emission sources. Although both particle and gas phase were sorbed by the PUFs, data of gas phase congeners are more reproducible.     

Effect of sewage sludges contaminated with polybrominated diphenylethers on agricultural soils

The fate of polybrominated diphenyl ethers (PBDEs) in sewage sludge after agricultural application was analysed. This study was based on the analysis of sewage sludge and sludge amended soil samples collected during 2005. PBDE concentrations in sewage sludge ranged from 197 to 1185ng/g dry weight (dw), being deca-BDE-209 the predominant congener. PBDE levels in soils ranged between 21 and 690ng/g dw, being BDE-209 also the predominant congener in all soil samples. Sewage-sludge amendment at the research stations increased concentrations of all BDE congeners 1.2- to 45-fold, with the highest increases for BDE-209. Results obtained evidenced the cumulative effect of the sludge application rates. Moreover, high levels found at soils four years after the last sludge application indicate persistence of PBDEs in soils, including deca-BDE-209.     

Trace organic chemicals contamination in ground water recharge

Population growth and unpredictable climate changes will pose high demands on water resources in the future. Even at present, surface water is certainly not enough to cope with the water requirement for agricultural, industrial, recreational and drinking purposes. In this context, the usage of ground water has become essential, therefore, their quality and quantity has to be carefully managed. Regarding quantity, artificial recharge can guarantee a sustainable level of ground water, whilst the strict quality control of the waters intended for recharge will minimize contamination of both the ground water and aquifer area. However, all water resources in the planet are threatened by multiple sources of contamination coming from the extended use of chemicals worldwide. In this respect, the environmental occurrence of organic micropollutants such as pesticides, pharmaceuticals, industrial chemicals and their metabolites has experienced fast growing interest. In this paper an overview of the priority and emerging organic micropollutants in the different source waters used for artificial aquifer recharge purposes and in the recovered water is presented. Besides, some considerations regarding fate and removal of such compounds are also addressed.     

Concentrations of PCDD/PCDFs in plasma of subjects living in the vicinity of a hazardous waste incinerator: follow-up and modeling validation

In 2007, the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) were determined in plasma of non-occupationally exposed subjects living near the only hazardous waste incinerator (HWI) in Spain (Constantí, Tarragona County, Catalonia). These data were compared with the levels found in two previous surveys performed in 1998 (baseline) and 2002. The current mean PCDD/PCDF concentration in plasma was 9.36pg I-TEQg(-1) of lipid (range: 1.76-23.44pg I-TEQg(-1) of lipid). It means a significant reduction of the mean PCDD/PCDFs levels in plasma in comparison to the concentrations found in 1998 and 2002 (27.01 and 15.70pg I-TEQg(-1) of lipid, respectively). This important decrease agrees well with the notable reduction in the dietary intake of PCDD/PCDFs recently noted for the population of the same area (210.1pg I-TEQd(-1), 63.8pgWHO-TEQd(-1), and 27.8pgWHO-TEQd(-1), in 1998, 2002 and 2007, respectively). The current data were also used to predict theoretical PCDD/PCDF concentrations in plasma by executing a single-compartment empirically-based pharmacokinetic model on the basis of the daily intake of these pollutants by the local population.     

Congener distribution of polybrominated diphenyl ethers in feral carp (Cyprinus carpio) from the Llobregat River, Spain

Feral carp were collected at two Spanish rivers, Anoia and Cardener, showing PBDE levels from 29 to 638 ng/g lipid weight (lw) and from 54 to 744 ng/g lw, respectively. Sediments were also collected, showing PBDE contamination between 2 and 10 ng/g dry weight (dw). Differences in PBDE profiles between sediments and fish were noticed. Contribution of BDE-47 in sediment was up to 11%, whereas it contributed 37-90% of PBDEs in fish. Similar results were observed for BDE-154, which was only detected in one sediment sample, but presented high contribution in carp. In contrast, BDE-99 contributed up to 32% in sediments, but it was not detected in fish. Similar results were observed for BDE-153, BDE-183 and BDE-209. The main reason for their concentration decrease or absence in biota may be due to low bioavailability potential or due to biotransformation processes.     

PM sources in a highly industrialised area in the process of implementing PM abatement technology. Quantification and evolution

Principal component analysis (PCA) coupled with a multilinear regression analysis (MLRA) was applied to PM(10) speciation data series (2002-2005) from four sampling sites in a highly industrialised area (ceramic production) in the process of implementing emission abatement technology. Five common factors with similar chemical profiles were identified at all the sites: mineral, regional background (influenced by the industrial estate located on the coast: an oil refinery and a power plant), sea spray, industrial 1 (manufacture and use of glaze components, including frit fusion) and road traffic. The contribution of the regional background differs slightly from site to site. The mineral factor, attributed to the sum of several sources (mainly the ceramic industry, but also with minor contributions from soil resuspension and African dust outbreaks) contributes between 9 and 11 microg m(-3) at all the sites. Source industrial 1 entails an increase in PM(10) levels between 4 and 5 microg m(-3) at the urban sites and 2 microg m(-3) at the suburban background site. However, after 2004, this source contributed less than 2 microg m(-3) at most sites, whereas the remaining sources did not show an upward or downward trend along the study period. This gradual decrease in the contribution of source industrial 1 coincides with the implementation of PM abatement technology in the frit fusion kilns of the area. This relationship enables us to assess the efficiency of the implementation of environmental technologies in terms of their impact on air quality.     

Distribution of polycyclic aromatic hydrocarbons (PAHs) and tributyltin (TBT) in Barcelona harbour sediments and their impact on benthic communities

Sediments have long been recognised as a sink for many contaminants like polycyclic aromatic hydrocarbons (PAHs) and tributyltin (TBT), which by virtue of their nature can strongly adsorb onto sediments affecting the benthic community inhabiting them. Using geographical information systems, this study reports and combines the results of several already existing studies along Barcelona harbour in order to assess the potential ecological impacts of these contaminants on the benthos of the harbour ecosystem. Chemical analysis indicated low to moderate contents of PAHs and high contents of TBT in sediments in Barcelona harbour. Comparison against existing sediment quality guidelines (SQGs) indicated that acutely toxic effects would not be expected for PAHs but for TBT, which represents a serious environmental threat for the benthic community. Benthos surveys revealed a deterioration of the benthic community throughout the harbour, especially in the inner port.     

Comparison of bioassays by testing whole soil and their water extract from contaminated sites

The harmful effects of contaminants on the ecosystems and humans are characterised by their environmental toxicity. The aim of this study was to assess applicability and reliability of several environmental toxicity tests, comparing the result of the whole soils and their water extracts. In the study real contaminated soils were applied from three different inherited contaminated sites of organic and inorganic pollutants. The measured endpoints were the bioluminescence inhibition of Vibrio fischeri (bacterium), the dehydrogenase activity inhibition of Azomonas agilis (bacterium), the reproduction inhibition of Tetrahymena pyriformis (protozoon), and Panagrellus redivivus (nematode), the mortality of Folsomia candida (springtail), the root and shoot elongation inhibition of Sinapis alba (plant: white mustard) and the nitrification activity inhibition of an uncontaminated garden soil used as "test organism". Besides the standardised or widely used methods some new, direct contact ecotoxicity tests have been developed and introduced, which are useful for characterisation of the risk of contaminated soils due to their interactive nature. Soil no. 1 derived from a site polluted with transformer oil (PCB-free); Soil no. 2 originated from a site contaminated with mazout; Soil no. 3 was contaminated with toxic metals (Zn, Cd, Cu, Pb, As). In most cases, the interactive ecotoxicity tests indicated more harmful effect of the contaminated soil than the tests using soil extracts. The direct contact environmental toxicity tests are able to meet the requirements of environmental toxicology: reliability, sensibility, reproducibility, rapidity and low cost.