| 1. |
- Adelsköld, Göran
(författare)
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Basin characteristics and nutrient losses: the EUROHARP catchment network perspective
- 2009
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 11, s. 515-525
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Tidskriftsartikel (refereegranskat)abstract
- The EC-funded EUROHARP project studies the harmonisation of modelling tools to quantify nutrient losses from diffuse sources. This paper describes a set of study areas used in the project from geographical conditions, to land use and land management, geological and hydro-geological perspectives. The status of data availability throughout Europe in relation to the modelling requirements is presented. The relationships between the catchment characteristics and the nutrient export are investigated, using simple data available for all the catchments. In addition, this study also analyses the hydrological representativity of the time series utilised in the EUROHARP project.
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| 2. |
- Alakangas, Lena, et al.
(författare)
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Simulation of pyrite oxidation in fresh mine tailings under near-neutral conditions
- 2012
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Ingår i: Journal of Environmental Monitoring. - 1464-0325 .- 1464-0333. ; 14:8, s. 2245-2253
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Tidskriftsartikel (refereegranskat)abstract
- Sulphidic residual products from ore processing may produce acid rock drainage, when exposed to oxygen and water. Predictions of the magnitude of ARD and sulphide oxidation rates are of great importance in mine planning because they can be used to minimize or eliminate ARD and the associated economic and environmental costs. To address the lack of field data of sulphide oxidation rate in fresh sulphide-rich tailings under near-neutral conditions, determination and simulation of the rate was performed in pilot-scale at Kristineberg, northern Sweden. The quality of the drainage water was monitored, along with oxygen and carbon dioxide concentrations. The chemical composition of the solid tailings was also determined. The field data were compared to predictions from simulations of pyrite oxidation using a 1-D numerical model. The simulations' estimates of the amount of Fe and S released over a seven year period (52 kg and 178 kg, respectively) were in reasonably good agreement with those obtained by analysing the tailings (34 kg and 155 kg, respectively). The discrepancy is probably due to the formation of secondary precipitates such as iron hydroxides and gypsum; which are not accounted for in the model. The observed mass transport of Fe and S (0.05 and 1.0 kg per year, respectively) was much lower than expected on the basis of the simulations and the core data. Neutralization reactions involving carbonates in the tailings result in a near-neutral pH at all depths except at the oxidation front (pH < 5), indicating that the dissolution of carbonates was too slow for the acid to be neutralized, which instead neutralized deeper down in the tailings. This was also indicated by the reduced abundance of solid Ca at greater depths and the high levels of carbon dioxide both of which are consistent with the dissolution of carbonates. It could be concluded that the near-neutral pH in the tailings has no decreasing effect on the rate of sulphide oxidation, but does reduce the concentrations of dissolved elements in the drainage water due to the formation of secondary minerals. This means that sulphide oxidation rates may be underestimated if determined from drainage alone.
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| 3. |
- Amer, Ranya, et al.
(författare)
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Diversity of hepatotoxic cyanobacteria in the Nile Delta, Egypt
- 2009
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 11:1, s. 126-133
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Tidskriftsartikel (refereegranskat)abstract
- Optimized denaturing gradient gel electrophoresis (DGGE) fingerprinting and real-time PCR were performed to identify and quantify the potential hepatotoxic microcystin-and nodularin-producing cyanobacteria present in freshwater samples collected during different seasons at three different sites from the Nile River Delta. The combined use of molecular gene markers (targeting the aminotransferase domain of the hepatotoxin synthetase modules and the 16S rRNA gene) and light microscopy demonstrated the dominance of different freshwater Microcystis phylotypes, including the potential hepatotoxin producers M. wesenbergii and M. aeruginosa, several Synechococcus and Cyanobium phylotypes, as well as the presence of Nodularia spumigena and Cylindrospermopsis raciborskii in the samples ""collected during summer 2006 and winter 2007''. Certain seasonal changes (summer and winter) in Microcystis microdiversity were detected. Real-time PCR revealed no difference in the quantities of potential hepatotoxin-producing cyanobacterial communities between summer and winter, but did show differences between the three sampling sites investigated. The expression of the aminotransferase domain analyzed by DGGE fingerprinting demonstrated that all Microcystis phylotypes present in the samples might have been active at the time of the sampling. Statistical analysis showed a significant effect of TP, and not TN, on the relative abundance of the potentially hepatotoxic cyanobacterial community.
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| 4. |
- Andrén, Cecilia M, et al.
(författare)
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Which aluminium fractionation method will give true inorganic monomeric Al results in fresh waters (not including colloidal Al)?
- 2009
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 11:9, s. 1639-1646
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Tidskriftsartikel (refereegranskat)abstract
- Aluminium solubility and toxicity increase with acidification. There is no standardized analytical method for the determination of inorganic monomeric Al (Alim), which is the form that causes toxicity to fish. Separation by cation exchange is commonly combined with other analytical methods, such as complexation with pyrochatechol violet (PCV) or 8-hydroxyquinoline (HQ) and total quantification using graphite furnace or inductively-coupled plasma emission. Data from 14 laboratories were obtained for a dilution series of Alim samples; the results of the Alim analysis were statistically evaluated. The Alim levels were altered through pH, which was controlled by the addition of calcium hydroxide. Confounding parameters such as total organic carbon (TOC) or fluoride (F) were controlled. The total determination and HQ methods yielded significantly higher Alim concentrations than the PCV method. Pretreatment by passage through a 0.45 µm filter and pH-adjustment of the ion exchange column had no apparent effect on the Alim yield. However, ultra filtration (<10 kDa) caused a significant reduction in the Alim concentration using the HQ method. The ultra filtrated Alim fraction was similar to the PCV results in the interlaboratory comparison. Retention of colloidal bound Al in the cation exchange column may result in overestimation of Alim when the total and HQ methods are used. Estimated Alim concentrations derived from two equilibrium models were similar to PCV-derived Alim concentrations, as well as the HQ method using ultra filtrated water. The fact that the PCV method does not detect colloidal Al, neither before nor after ion exchange, makes this a preferred technique for Alim analysis. Because of the variability in the reported Alim concentrations that can arise when different analytical procedures are used, the adoption of a single, reliable technique will facilitate inter-study comparisons and provide consistency in the detection of trends in environmental monitoring programs.
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| 5. |
- Appelblad, Petra K., et al.
(författare)
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Determination of metal-humic complexes, free metal ions and total concentrations in natural waters
- 1999
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Ingår i: Journal of Environmental Monitoring. - 1464-0325 .- 1464-0333. ; 1:3, s. 211-217
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Tidskriftsartikel (refereegranskat)abstract
- A comparison of two systems for the quantitation of metal-humic complexes and free metal ions, consisting of the separation by coupled ion exchange columns followed by detection by inductively coupled plasma mass spectrometry or cold vapour atomic fluorescence spectrometry, is presented. The systems evaluated comprised the serially coupled anion and cation exchangers, Sephadex A-25/Chelex 100 and Dowex 1X8/Chelamine Metalfix. Separation and preconcentration of the species studied were accomplished with both systems, elution being carried out using 2 M HNO3. Total concentrations, metal-humic complex fractions and free metal ion fractions of Al, Ba, Cd, Co, Cu, Fe, Hg, Mn, Pb, Sr, U and Zn in nine natural waters were determined. Statistical evaluation of the data from the two cation exchange materials, including results for additional elements, showed better precision (for Al, Ba, Cr, Cu and Mo) and higher recoveries (Al, Ba, Cd, Fe, Sr and Zn) for Chelex 100 than Chelamine Metalfix for free metal ions. On the other hand, Chelamine Metalfix recovered a significantly greater amount of Ni. The amounts of metal-humic complexes were compared with modelled distributions of these species, and one advantage of the preferred Sephadex A-25/Chelex 100 system is that the elements studied are all correctly classified with respect to their binding strengths to humic substances, which is not the case with the Dowex 1X8/Chelamine Metalfix pair. With the preferred system, metal-humic complexes can be reliably determined, as indicated by the results of equilibrium speciation modelling. However, comparison with the total concentrations showed statistically significant, non-quantitative recoveries of Al, Cu, Hg, Mn, U and Zn from some samples. Thus a combination of speciation and total concentration measurements is required to obtain a complete representation of the distribution of trace elements in natural waters.
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| 6. |
- Arp, Hans Peter H, et al.
(författare)
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Presence and partitioning properties of the flame retardants pentabromotoluene, pentabromoethylbenzene and hexabromobenzene near suspected source zones in Norway
- 2011
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Ingår i: Journal of Environmental Monitoring. - : RSC Publishing. - 1464-0325 .- 1464-0333. ; 13:3, s. 505-513
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Tidskriftsartikel (refereegranskat)abstract
- The brominated flame retardants (BFRs), pentabromotoluene (PBT), pentabromoethylbenzene (PBEB) and hexabromobenzene (HBB), exhibit physical-chemical properties similar to other persistent organic pollutants, and have been in use as flame retardants for several decades. Data on these BFRs in diverse environmental samples can be found in studies from the 1970s and 1980s, as well as in recent years, though very little in the years in between. Due to a lack of data, the cause for the apparent re-emergence of these BFRs in recent studies is unclear, and could reflect changes in production volumes, accumulation of transformation products from BFR precursors, improved analytical techniques or simply a re-emergence in concern. Very little data are available on their environmentally relevant partitioning properties, which could help to explain the occurrence and fate of these BFRs. In this study we analysed for the presence of HBB, PBT, and PBEB in diverse environmental samples from potential Norwegian BFR source zones. Additionally, environmental partitioning properties of these BFRs as well as brominated benzenes were estimated and validated using experimental data for brominated benzenes. Of the three BFRs, HBB was identified in detectable quantities at most source zones, PBEB only near a metal recycling factory, and PBT only in a few additional locations from where PBEB was detected. Data from this study show that HBB is likely widely distributed, as verified both by chemical analysis and estimated properties. Measured HBB levels in wastewater treatment plants indicate that the treatment practices used in the study locations are not effective at lowering HBB levels, perhaps due to association with low density suspended solids (e.g. microplastics).
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| 7. |
- Axelsson, Sara, et al.
(författare)
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Determination of resin acids during production of wood pellets-a comparison of HPLC/ESI-MS with the GC/FID MDHS 83/2 method
- 2011
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Ingår i: Journal of Environmental Monitoring. - Cambridge : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 13:10, s. 2940-2945
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Tidskriftsartikel (refereegranskat)abstract
- Resin acids are constituents of natural and technical products of widespread use. Exposure is known to cause health effects in the airways and on the skin. Liquid chromatography/positive ion electrospray-mass spectrometry (HPLC/pos ESI-MS) was investigated for determination of 7-oxodehydroabietic (7-OXO), dehydroabietic (DHAA) and abietic acid (AA) in wood dust-containing air samples as a derivatisation-free alternative to the GC/FID HSE method 83/2, developed by the Health and Safety Executive UK. The resin acid 7-OXO was measured as a marker for oxidised resin acids, which are known to be the main contact allergens in colophonium. The found detection limits were 0.42 ng m(-3) for 7-OXO, 5.2 ng m(-3) for DHAA and 9.4 ng m(-3) for AA, respectively, which are considerably lower than with the GC/FID method (24, 115 and 89 ng m(-3)). The two methods correlated well, although consistently and significantly lower concentrations of 7-OXO were detected with LC/MS. The higher concentration of this compound with MDHS 83/2 is suggested to be an artefact from the derivatisation step in the presence of soluble wood dust remains.
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| 8. |
- Bergemalm-Rynell, kerstin, 1949, et al.
(författare)
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Laboratory and field evaluation of a diffusive sampler for measuring halogenated anesthetic compounds
- 2008
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Ingår i: J Environ Monit. - : Royal Society of Chemistry (RSC). - 1464-0325. ; 10, s. 1172-78
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Tidskriftsartikel (refereegranskat)abstract
- Anesthetic gases such as desflurane, sevoflurane, isoflurane, enflurane, and halothane are used on a daily basis in operating theaters. Active sampling has historically been used to control the level of exposure to personnel. SKC 575-002 is a diffusive passive sampler filled with Anasorb 747. We validated this sampler in both laboratory and field experiments. Parameters tested were desorption efficiency, concentration, sampling time, relative humidity, and reverse diffusion, as well as storage stability for up to 8 weeks. Uptake rates were achieved by comparison with active sampling for each passive sampling trial of 1, 4, or 8 h. Analysis and detection were performed using gas chromatography with flame ionization detection (GC/FID). Multiple regression analysis was used to evaluate the influence of time, concentration, dose, and relative humidity. In the field evaluation experiments, intraclass correlation coefficients (ICC) were estimated. In the laboratory experiments, no problems were found with storage stability or reverse diffusion. The sampling rates for the five anesthetics vary, however, with exposure time and exposure level, with generally higher uptake rates at low concentrations and short sampling times. In the field experiments there was high agreement between the active and passive samplers for halothane, sevoflurane, and isoflurane (ICC > 0.83). When performing whole-day workplace measurements (TWA measurements) the SKC 575-002 can be recommended, and at levels around 1 ppm the following uptake rates should be used: enflurane and halothane, 12.3 mL min−1; desflurane, 13.6 mL min−1; isoflurane, 12.0 mL min−1; and sevoflurane, 11.9 mL min−1.
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| 9. |
- Bergh, Caroline, et al.
(författare)
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Organophosphate and phthalate esters in indoor air : a comparison between multi-storey buildings with high and low prevalence of sick building symptoms
- 2011
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 13:7, s. 2001-2009
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Tidskriftsartikel (refereegranskat)abstract
- An extensive study has been conducted of the prevalence of organophosphorous flame retardants/plasticizers and phthalate ester plasticizers in indoor air. The targeted substances were measured in 45 multi-storey apartment buildings in Stockholm, Sweden. The apartment buildings were classified as high or low risk with regard to the reporting of sick building symptoms (SBS) within the project Healthy Sustainable Houses in Stockholm (3H). Air samples were taken from two to four apartments per building (in total 169 apartments) to facilitate comparison within and between buildings. Association with building characteristics have been examined as well as association with specific sources by combining chemical analysis and exploratory uni- and multivariate data analysis. The study contributes to the overall perspective of levels of organophosphate and phthalate ester in indoor air enabling comparison with other studies. The results indicated little or no difference in the concentrations of the target substances between the two risk classifications of the buildings. The differences between the apartments sampled within (inter) buildings were greater than the differences between (intra) buildings. The concentrations measured in air ranged up to 1,200 ng/m3 for organophosphate esters and up to 11,000 ng/m3 for phthalate esters. Results in terms of sources were discerned e.g. PVC flooring is a major source of benzylbutyl phthalate in indoor air.
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| 10. |
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