| 1. |
- de Boer, J., et al.
(författare)
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United Nations Environment Programme Capacity Building Pilot Project : training and interlaboratory study on persistent organic pollutant analysis under the Stockholm Convention
- 2008
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Ingår i: Analytica Chimica Acta. - : Elsevier BV. - 0003-2670 .- 1873-4324. ; 617:1-2, s. 208-215
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Tidskriftsartikel (refereegranskat)abstract
- Within the framework of a United Nations Environment Programme (UNEP) Capacity Building Project for training of laboratory staff in developing countries on persistent organic pollutant (POP) analysis, an interlaboratory study was organised following an initial evaluation of the performance of laboratories (reality check) and a series of training sessions. The target compounds were polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP). Seven laboratories from five countries (Ecuador, Uruguay, Kenya, Moldova, and Fiji) participated. Most of the laboratories had no experience in determining PCBs. Although chromatograms improved considerably after the training and installation of new gas chromatographic (GC) columns at participating laboratories, the level of performance in the interlaboratory study was essentially on par with the moderate performance level achieved by European POP laboratories in the 1980s. Only some individual results were within +/-20% of the target values. The relative standard deviations (R.S.D.s) in POP concentrations determined by laboratories in a sediment sample were >200% in a number of cases. The results for a certified herring sample were better with at least some R.S.D. values below 50% and most below 100%. Clean up was as one of the main sources of error. After inspection it was ascertained that training of laboratory staff and investments in simple consumables such as glassware and GC columns would help to improve the quality of the analysis more than major investments in expensive instrumentation. Creating an effective network of POP laboratories at different continents together with a series of interlaboratory studies and workshops is suggested to improve the measurements of POPs in these countries.
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| 2. |
- Hollert, Henner, et al.
(författare)
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Eine Weight-of-Evidence-Studie zur Bewertung der Sedimentbelastung und des Fischrückgangs in der Oberen Donau [Assessing sediments and fish health using a weight-of-evidence approach : in search for the causes of fish decline in the Danube river]
- 2009
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Ingår i: Umweltwissenschaften und Schadstoff-Forschung. - Berlin : Springer. - 0934-3504 .- 1865-5084. ; 21:3, s. 260-263
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Tidskriftsartikel (refereegranskat)abstract
- Background and aim Despite intensive and continuous stocking and improvement of water quality since the 1970s, fish populations, especially those of the grayling (Thymallus thymallus), have declined over the last two decades in the upper Danube River (Germany). In order to assess 1) possible links between molecular/biochemical responses and ecologically relevant effects, and 2) if ecotoxicological effects might be related to the decline in fish catches in the upper Danube river, sediment samples and fish were collected at different locations and analyzed using a weight-of-evidence (WOE) approach with several lines of evidence. The objective of the presentation is to introduce the conceptual framework and to review results of the ongoing study. As previously addressed by Chapman and Hollert (2006) a variety of lines of evidence can be used in WOE studies. Briefly, 1) a comprehensive battery of acute and mechanism-specific bioassays was used to characterize the ecotoxicological hazard potential. 2) Histopathological investigations and the micronucleus assay with erythrocytes were applied, analyzing in situ parameters. 3) Diversity and abundance of benthic macroinvertebrates and fish as well as 4) persistent organic pollutants, endocrine disrupting substances, limnochemical parameters and the concentration of heavy metals were recorded. To identify organic contaminants a spotential causes of sediment toxicity assays, 5) effect directed analysis was applied. © 2009 Springer-Verlag.
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| 3. |
- Löthgren, Carl-Johan, 1968-
(författare)
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Mercury and dioxins in a MercOx-scrubber
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The removal of mercury and the absorption of dioxins in an acid wet scrubber have been studied in industrial scale. Hydrogen peroxide is added as an oxidizing agent to the scrubber liquid with the purpose to remove SO2 and enhance the removal of mercury. The scrubber is operating as the final flue gas cleaning stage at the SAKAB plant, a hazardous waste incinerator in Sweden. Mercury speciation was measured in flue gases upstream and downstream of the scrubber with three different techniques: Impingers, solid phase absorbents and a continuous emission monitor. During the flue gas sampling periods also the scrubber liquid was sampled. It was found that mercury entering the scrubber is efficiently oxidized at normal operating conditions. An increased fraction of elemental gaseous mercury was found in flue gases after the scrubber at redox potentials below 700 mV and pH below 1. The mercury emissions were more dependent on the scrubber liquid composition than on the inlet concentrations. Equilibrium calculations of the mercury speciation in the scrubber liquid and flue gases after the scrubber showed that mercury is normally emitted as HgBr2 or HgCl2. Elemental bromine and chlorine are formed in the scrubber. Both species probably take part in the mercury oxidation process. Results from 18 months of dioxin sampling, using a continuous long term sampling device (the AMESA system) were evaluated by multivariate data analyses. It was shown that the elevated emissions observed were caused by a memory effect in the scrubber due to high start-up concentrations. The memory effect was modelled in a diffusion model where the dioxins were considered to be physically absorbed in and desorbed from the polypropylene fillings of the scrubber. From the diffusion model, the diffusivities for tetra to hexa chlorinated dioxins in polypropylene were calculated. The diffusivity of tetra chlorinated dioxins was calculated to be 10-14 m2/s. The diffusivity decreases with increasing chlorination. For hexa chlorinated dioxins it was calculated to be 10-16 m2/s. Brominated dioxins were measured before and after a fabric filter. The fraction of brominated dioxins increased after the filter. Di brominated furans were the most abundant homologue.
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| 4. |
- van Leeuwen, Stefan P. J., et al.
(författare)
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Struggle for quality in determination of perfluorinated contaminants in environmental and human samples
- 2006
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 40:24, s. 7854-7860
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Tidskriftsartikel (refereegranskat)abstract
- The first worldwide interlaboratory study on the analyses of 13 perfluorinated compounds (PFCs) in three environmental and two human samples indicates a varying degree of accuracy in relation to the matrix or analyte determined. The ability of 38 participating laboratories from 13 countries to determine the analytes in the various matrices was evaluated by calculation of z-scores according to the Cofino model. The PFCs which were reported most frequently by the laboratories, and assessed with the most satisfactory agreement, were perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In general, the level of agreement between the participating laboratories decreased in the following order: PFC standard solution (76% satisfactory z-scores of <[2]1 for PFOS) < human blood (67%) < human plasma (63%) < fish liver extract (55%) < water (31%) < fish tissue (17%). This shows that relative good agreement between laboratories was obtained for the study of standard and human matrices. For the fish extract, most laboratories underestimated the actual PFOS concentration due to matrix effects. The results for the fish tissue and water are also poor, indicating that the extraction and cleanup steps require further improvement. It was concluded that the PFC determinations in various matrices are not yet fully mastered.
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| 5. |
- Wolkers, Hans, et al.
(författare)
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Accumulation and transfer of contaminants in killer whales (Orcinus orca) from Norway : indications for contaminant metabolism
- 2007
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Ingår i: Environmental Toxicology and Chemistry. - 0730-7268 .- 1552-8618. ; 26:8, s. 1582-1590
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Tidskriftsartikel (refereegranskat)abstract
- Blubber tissue of one subadult and eight male adult killer whales was sampled in Northern Norway in order to assess the degree and type of contaminant exposure and transfer in the herring-killer whale link of the marine food web. A comprehensive selection of contaminants was targeted, with special attention to toxaphenes and polybrominated diphenyl ethers (PBDEs). In addition to assessing exposure and food chain transfer, selective accumulation and metabolism issues also were addressed. Average total polychlorinated biphenyl (PCB) and pesticide levels were similar, approximately 25 microg/g lipid, and PBDEs were approximately 0.5 microg/g. This makes killer whales one of the most polluted arctic animals, with levels exceeding those in polar bears. Comparing the contamination of the killer whale's diet with the diet of high-arctic species such as white whales reveals six to more than 20 times higher levels in the killer whale diet. The difference in contaminant pattern between killer whales and their prey and the metabolic index calculated suggested that these cetaceans have a relatively high capacity to metabolize contaminants. Polychlorinated biphenyls, chlordanes, and dichlorodiphenyldichloro-ethylene (DDE) accumulate to some degree in killer whales, although toxaphenes and PBDEs might be partly broken down.
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| 6. |
- Covaci, Adrian, et al.
(författare)
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Evaluation of total lipids using enzymatic methods for the normalization of persistent organic pollutant levels in serum
- 2006
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 366:1, s. 361-366
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Tidskriftsartikel (refereegranskat)abstract
- The human exposure to persistent organic pollutants (POPs) is conveniently assessed through analysis of blood serum or plasma and the POPs concentrations are traditionally expressed on a lipid weight basis. Enzymatic determinations of total lipid (TL) content in serum, which imply the measurement of individual lipid classes, such as triglycerides (TG), cholesterol (CHOL) and phospholipid (PL), use small amounts of serum/plasma (<100 microl). These have also become a more precise and less laborious alternative for the gravimetric lipid determinations which were preferred in the past. However, PL are not routinely measured in most clinical laboratories and therefore, TL values are often predicted from formulas based on measurements of only TG and CHOL. In the present study, a large data set (n=483) from Belgian, Swedish and Norwegian populations was used to compute a new formula for TL [TL=1.33*TG+1.12*CHOL+1.48 (g/l)] by means of multiple linear regression. A very good correlation (r=0.949, p<0.001) was found between TL values calculated with the proposed formula and TL values obtained by summation of TG, CHOL and PL. Statistically different values of TL were computed when different previously published formulas were compared, which can have a strong influence on the calculation of lipid-normalized concentrations of POPs. Nevertheless, TL values derived using a mathematical formula which includes only TG and CHOL will be less accurate than TL values obtained by summation of TG, CHOL and PL, which should be the calculation method of choice if PL measurements are available.
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| 7. |
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| 8. |
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| 9. |
- Ericson Jogsten, Ingrid, et al.
(författare)
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Human exposure to perfluorinated chemicals through the diet : intake of perfluorinated compounds in foods from the Catalan (Spain) market
- 2008
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 56:5, s. 1787-1794
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to determine the dietary intake of perfluorinated chemicals (PFCs) by the population of Tarragona County (Catalonia, Spain). PFC levels were determined in 36 composite samples of foodstuffs randomly purchased in various locations. Exposure to PFCs through the diet was estimated for various age/gender groups. Perfluorooctane sulfonate (PFOS), perfluorocarboxylate perfluorooctanoate (PFOA), and perfluoroheptanoic acid (PFHpA) were the only detected PFCs in foodstuffs. On average, for a standard adult man (70 kg of body weight), the dietary intake of PFOS was estimated to be 62.5 or 74.2 ng/day (assuming ND=0 or ND=1/2 LOD, respectively). Fish, followed by dairy products and meats, were the main contributors to PFOS intake. For an adult man, the intake of PFOS (1.07 ng/kg/day) and those of PFOA and PFHpA were lower than that recently reported for Canada (4.0 ng/kg/day), and considerably lower than that previously found in the United Kingdom, the only two countries where, to date, results concerning this issue have been reported. A correlation between dietary intake and blood levels of PFOS is suggested. However, the current results do not justify dietary intake as the main route of exposure governing blood concentrations of other PFCs.
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| 10. |
- Ericson Jogsten, Ingrid, et al.
(författare)
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Levels of perfluorinated chemicals in municipal drinking water from Catalonia, Spain : public health implications
- 2009
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 57:4, s. 631-638
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the concentrations of 13 perfluorinated compounds (PFCs) (PFBuS, PFHxS, PFOS, THPFOS, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFTDA, and PFOSA) were analyzed in municipal drinking water samples collected at 40 different locations from 5 different zones of Catalonia, Spain. Detection limits ranged between 0.02 (PFHxS) and 0.85 ng/L (PFOA). The most frequent compounds were PFOS and PFHxS, which were detected in 35 and 31 samples, with maximum concentrations of 58.1 and 5.30 ng/L, respectively. PFBuS, PFHxA, and PFOA were also frequently detected (29, 27, and 26 samples, respectively), with maximum levels of 69.4, 8.55, and 57.4 ng/L. In contrast, PFDoDA and PFTDA could not be detected in any sample. The most contaminated water samples were found in the Barcelona Province, whereas none of the analyzed PFCs could be detected in two samples (Banyoles and Lleida), and only one PFC could be detected in four of the samples. Assuming a human water consumption of 2 L/day, the maximum daily intake of PFOS and PFOA from municipal drinking water would be, for a subject of 70 kg of body weight, 1.7 and 1.6 ng/kg/day. This is clearly lower than the respective Tolerable Daily Intake set by the European Food Safety Authority. In all samples, PFOS and PFOA also showed lower levels than the short-term provisional health advisory limit for drinking water (200 ng PFOS/L and 400 ng PFOA/L) set by the US Environmental Protection Agency. Although PFOS and PFOA concentrations found in drinking water in Catalonia are not expected to pose human health risks, safety limits for exposure to the remaining PFCs are clearly necessary, as health-based drinking water concentration protective for lifetime exposure is set to 40 ng/L for PFOA.
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