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Eiliv Steinnes

Publications and source records attributed to Eiliv Steinnes.

At least 19 recordsLinked to original sources
PubMed2006

Dynamic aspects of DGT as demonstrated by experiments with lanthanide complexes of a multidentate ligand.

Sampling of metals with the technique of diffusive gradients in thin-films (DGT) depends on the rates of diffusion and on the kinetics of interconversion of the species present. In this study the discrimination between metal complexes with different dissociation kinetics is investigated. Samplers with differentthicknesses of diffusive and resin gels were deployed in solutions containing 10 microg/L of each metal in the lanthanide (Ln) series (except Pm) and 2.0 x 10(-6) M of the ligand quin2 at an ionic strength of 0.1 M (KNO3) and pH 7.0. Diffusion coefficients of Ln3+ ions and Ln-quin2 complexes were determined in a diffusion cell experiment. The equilibrium speciation of the metals was calculated from available stability constants. The sampling rate (mass/time) was highly dependent on the dissociation-rate constant of the complexes. For complexes with dissociation kinetics that appreciably limited the uptake, the sampling rate decreased significantly with increasing deployment times (12, 24, and 76 h) and was virtually independent of the thickness of the diffusive gel. Placing a layer of diffusive gel behind the resin did not influence the accumulation of Lns in the resin gel, but doubling the thickness of the layer containing resin increased the uptake, and more so for the Lns forming less labile complexes. The Lns forming more labile complexes were enriched in the outer layer of the resin, and there was a trend toward even distribution between the outer and deeper parts of the resin layer for the Lns forming less labile complexes. The measured DGT sampling rates (mass/ time) were reasonably well predicted by a dynamic model that used independently determined kinetic constants. This new knowledge of how metal complexes behave in the sampling process paves the way for using DGT to obtain in situ kinetic information in natural waters.

Biophysics↗
PubMed2006

Persistent organic pollutants in European background air: derivation of temporal and latitudinal trends.

Data are presented for polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyls ethers (PBDEs) and selected organochlorine compounds (OCs) in passive air samplers (PAS) along a rural/remote latitudinal transect from southern UK to northern Norway during 2002-2004. This study is part of an ongoing campaign, using semi-permeable membrane devices (SPMDs) as PAS over two year intervals since 1994. Data for PCBs, selected OCs and PBDEs are compared with that from previous campaigns. Absolute sequestered amounts of selected PCB congeners have decreased in a first order fashion between 1994-2004, with an average atmospheric clearance rate of 4.1 +/- 0.6 years and continue to fractionate with latitude. HCB has also declined between 1998-2004, with a clearance rate of 6 +/- 2.4 years. Data on DDT and its breakdown products indicate little fresh release in Europe. Comparison of PBDEs in 2000-02 and 2002-04 indicates site differences, generally with increases at UK sites and decreases in Norway. BDE-28, 47 and 49 decreased with increasing latitude (p < 0.04), while the other congeners did not show any significant latitudinal dependence. Transect data are presented for PAHs the first time. Three- and 4-ringed compounds dominated the mixture present in the SPMD. The PAH composition of the SPMDs at site 3 was compared to the average composition taken by active sampling at the same site. SPMD performance for sampling PAHs leaves many uncertainties, but they can be successfully used to semiquantitatively detect PAHs in the atmosphere. Fluorene and phenanthrene increased with latitude (p > 0.05), while 1-methylphenanthere, fluoranthene, benzo[b]fluoranthene and indeno[123-cd]pyrene decreased. Results are discussed in terms of sources, long-range atmospheric transport, global fractionation and clearance processes.

Air Pollutants↗
PubMed2006

Heavy metal pollution of surface soil in the Thrace region, Turkey.

Samples of surface soil were collected at 73 sites in the Thrace region, northwest part of Turkey. Two complementary analytical techniques, epithermal neutron activation analysis (ENAA) and atomic absorption spectrometry (AAS) with flame and graphite furnace atomization were used to determine 35 elements in the soil samples. Concentrations of As, Cd, Co, Cu, Mn, Ni, Pb and Zn were determined using AAS and GF AAS, and ENAA was used for the remaining 27 elements. Results for As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu Eu, Fe, Hf, I, In, K, La, Mn, Mo, Na, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, Ti, U, V and Zn are reported for the first time for soils from this region. The results show that concentrations of most elements were little affected by the industrial and other anthropogenic activities performed in region. Except for distinctly higher levels of Pb, Cu, Cd and Zn in Istanbul district than the median values for the Thrace region, the observed distributions seem to be mainly associated with lithogenic variations. Spatial distributions of As, Cd, Cr, Cu, Ni, Pb and Zn were plotted in relation to the concentration values in soil using Geographic Information System (GIS) technology.

Environmental Monitoring↗
PubMed2005

Atmospheric mercury in Norway: contributions from different sources.

The environmental loadings of national Norwegian mercury emissions compared to the loadings of atmospheric long range transported mercury have been estimated using national emission data and EMEP model data. The results indicate that atmospheric long-range transport to Norway is somewhat larger than the national Norwegian emissions of mercury. Atmospheric deposition of mercury has been studied using data from Norwegian monitoring programs on mercury in precipitation, mosses, natural surface soils, and lake sediments. Precipitation data show no significant time trend during 1990-2002, whereas moss samples show similar concentrations from 1985 to 1995, but a 30% decrease from 1995 to 2000. Concentrations of mercury in peat cores and reference sediments indicate that the current mercury levels measured in surface sediments, surface soils and mosses at background sites in Norway are substantially affected by long-range atmospheric transport.

Air Movements↗
PubMed2005

(90)Sr, (210)Po and (210)Pb in lichen and reindeer in Norway.

Concentrations of (90)Sr, (210)Po and (210)Pb in lichen and reindeer were studied in central (Østre Namdal) and southern Norway (Vågå) during 2000-2003. The study focussed on potential differences in concentrations of these nuclides in reindeer of different ages. Concentrations of (90)Sr in bones of approximately 10 year old adult females were about 40% higher than those in calves' antlers ((90)Sr concentrations in antlers and bones of calves are similar), while the available data from Vågå suggest that (90)Sr concentrations in reindeer calves decreased with an effective ecological half-time of 9.03+/-0.06 years during 1988-2002. Furthermore, (90)Sr concentrations were 50-80% higher in bone of reindeer of a similar age from Vågå compared to those from Østre Namdal. Concentrations of (210)Po and (210)Pb in muscle and liver tissues were comparable to those reported for reindeer in other Nordic areas, with no significant difference in (210)Po and (210)Pb concentrations between adults and calves or between reindeer from the two different study areas.

Age Factors↗
PubMed2005

PCDD/Fs in Norwegian and U.K. soils: implications for sources and environmental cycling.

This paper presents data on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in a set of well-characterized, undisturbed surface (0-5 cm) and subsurface background soils from the U.K. and Norway. The soils have been used previously to investigate the latitudinal distribution, fractionation, cold condensation, and "hopping" of other classes of persistent organic pollutants (POPs). The mono- to octa-CDD/F homologues were quantified. Woodland soils contained higher concentrations (on a dry and soil organic matter (SOM)-basis) than grassland soils, consistent with previous studies. The absolute concentrations of all the PCDDs and most of the PCDFs significantly decreased with latitude, generally supporting the idea of a "southern source region" and a "remote/ receiving northern region". There was little evidence of "fractionation" and minimal influence of PCDD/F "hopping" on PCDD/F distribution. The %SOM content had a rather minor influence on soil PCDD/F composition. These findings contrast with the trends seen in these soils for hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Possible reasons for these differences are discussed and may include influences of/proximity to diffusive combustion sources and/ or sources of variable homologue emissions, formation/ conversion processes for PCDD/Fs in soils, or strong soil-PCDD/F partitioning. These soils, from regionally remote/ background locations in Europe contained between 0.2 and 78 pg sigmaTEQ/g DW. Some therefore exceed recommended levels of contamination for certain land uses by some European countries. These recommendations seem unrealistic and prohibitively restrictive in light of the dataset presented here.

Benzofurans↗
PubMed2005

Diffusive gradients in thin films sampler predicts stress in brown trout (Salmo trutta L.) exposed to aluminum in acid fresh waters.

Increased levels of aluminum ions released from nutrient-poor soils affected by acid rain have been the primary cause of fish deaths in the acidified watersheds of southern Norway. The complex aluminum chemistry in water requires speciation methods to measure the gill-reactive species imposing toxic effects toward fish. Previously, aluminum speciation has mainly followed the fractionation principles outlined by Barnes/Driscoll, and several analogues of these fractionation principles have been used both in situ and in the laboratory. Due to rapid transformation processes, aluminum speciation in water samples may change even during short storage times. Thus, results obtained by laboratory fractionation methods might be misleading for the assessment of potentially toxic aluminum species in the water. Until now, all in situ field fractionation methods have been time and labor consuming. The DGT technique (diffusive gradients in thin films) is a new in situ sampler collecting a fraction of dissolved metal weighted according to the rate of diffusion and dissociation kinetics. In a field experiment with acid surface water we studied the DGT sampler as a new prediction tool for the gill accumulation of aluminum in trout (Salmo trutta L.) and the induced physiological stress responses measured as changes in blood glucose and plasma chloride. Aluminum determined with DGT (DGT-AI) was higher than labile monomeric aluminum (Ali) determined with a laboratory aluminum fractionation procedure (PCV--a pyrocatechol violet analogue of Barnes/Driscoll), a difference due to collection of a fraction of organically complexed aluminum by DGT and a reduction of the Ali fraction during sample storage. DGT-AI predicted the gill uptake and the aluminum-induced physiological stress responses (increased blood glucose and decreased plasma chloride, r2 from 0.6 to 0.9). The results indicate that DGT-AI is a better predictor for the stress response than laboratory-determined Ali, because the DGT sampler collects a more correct fraction of the gill-reactive aluminum species that induces the stress.

Aluminum↗
PubMed2005

Order-of-magnitude increase of Hg in Norwegian peat profiles since the outset of industrial activity in Europe.

Peat cores from six ombrotrophic bogs at different latitudes in Norway (58 degrees N-69 degrees N) were analysed for Hg by atomic fluorescence spectrometry. In all cases a smooth decrease of Hg with depth was observed down to 15-20 cm. At greater depths Hg showed a relatively constant level of the order of 10% of that in the peat surface layer. In the surface peat Hg concentrations exhibit moderate variation with latitude. The pre-industrial levels of Hg in the peat correspond to a net annual Hg accumulation of 0.3-0.9 microgm(-2). The Hg accumulation over the last 100 years is about 15 times higher on average than the pre-industrial level. The present work supports the view that a major part of the present atmospheric Hg in the Northern Hemisphere is of anthropogenic origin. It is speculated that the comparatively high Hg contemporary accumulation rates observed at the Andøya bog on 69 degrees N may be related to the Arctic springtime depletion of Hg.

Agriculture↗
PubMed2005

Concentrations of 137Cs in lynx (Lynx lynx) in relation to prey choice.

Concentrations of (137)Cs were determined in 747 lynxes killed in Norway during the period 1986-2001. Highly variable (137)Cs concentrations and aggregated transfer coefficient values were observed, probably caused by variable (137)Cs concentrations in prey and the lynx's extensive home ranges and roaming distances. Adult lynxes had higher (137)Cs concentrations than sub-adults, and lynxes killed in regions with extensive reindeer grazing areas were more contaminated than others. A model with (137)Cs deposition density, the year lynxes were killed, age, and extent of reindeer grazing area accounted for 50% of the variability in observed (137)Cs concentrations. The analyses were equivocal regarding the influence of stomach content on (137)Cs concentrations in lynx muscle, i.e., on the lynx's specialization in prey species. Gender was not significant. Information on caesium retention in lynx and better estimates of deposition densities in lynxes' home ranges are important for further elucidation of factors influencing (137)Cs contamination in lynxes.

Animals↗
PubMed2005

Chernobyl radioactivity persists in reindeer.

Transfer of 137Cs in the soil-plant/lichen-reindeer food chain was studied in central (Østre Namdal) and southern Norway (Vågå) during 2000-2003. Reindeer from these areas have been continuously subjected to countermeasure application since the 1986 Chernobyl accident. In both areas no decline in 137Cs concentrations was detectable in reindeer slaughtered in autumn since 1995, or in reindeer slaughtered in winter since 1998-1999. Seasonal differences in 137Cs concentrations in reindeer have been less pronounced in recent years, with 137Cs concentrations occasionally higher in autumn than in winter. Soil-to-plant 137Cs transfer was significantly higher in Østre Namdal than in Vågå. Climatic influences on lichen growth and abundance, and on soil properties that influence the availability of 137Cs for plant uptake, are hypothesized to have a larger impact on long-term transfer of radiocaesium in the soil-plant/lichen-reindeer food chain than has been previously observed.

Animals↗
PubMed2005

Damage to DNA and lipids in Boletus edulis exposed to heavy metals.

This study investigates the potential of emissions from a zinc smelter to induce oxidative damage to DNA and lipids in Boletus edulis, the king bolete. Concentrations of cadmium, zinc, copper, and mercury were determined in 16 fruit bodies collected near the smelter (exposed group), as well as in 15 reference samples. Frequency of apurinic/apyrimidinic (AP) sites in DNA (a pre-mutagenic DNA base modification) and concentration of lipid hydroperoxides were chosen as damage parameters. Concentrations of the four metals, as well as oxidative damage to DNA and lipids were significantly elevated in the exposed group (Mann-Whitney, P<0.001). Both damage parameters correlated positively with concentrations of cadmium, zinc or copper in fruiting bodies (Spearman's P<0.01). Frequency of AP sites correlated significantly with mercury in the fruit bodies (P<0.05), whereas the association between lipid hydroperoxides and mercury was insignificant. Frequency of AP sites correlated positively with concentration of lipid hydroperoxides (P<0.001). Negative trends for the associations between concentrations of metals and AP sites or lipid hydroperoxides in the reference group (significant only for mercury and lipid hydroperoxides; P<0.05) suggest that in B. edulis low concentrations of mercury, possibly also of other of the metals determined in the present study, may induce dose-response relationships of a hormetic ('J-shaped') nature.

Basidiomycota↗
PubMed2004

Seasonal concentrations of cadmium and zinc in native pasture plants: consequences for grazing animals.

Aboveground concentrations of Cd and Zn in various grazing plants at three stages of the growing season are reported. The plants were collected at a natural habitat exposed to extensive atmospheric deposition of heavy metals from other parts of Europe. Concentrations of both metals varied considerably among species, also among morphologically similar species growing in the same soil. The two metals correlated in the material as a whole, but the concentration variations were most pronounced for Cd. There were also seasonal variations (generally a concentration reduction during spring). Transfer of metals from twigs to leaves seemed to differ between 'high' and 'low' metal accumulators. The inter-species and seasonal variations in plant metal concentrations complicate assessments of metal exposure to grazing animals through diet. By using diet information from a study conducted in an area similar to the present one, we roughly estimated a daily intake of 1-2 mg Cd for moose (Alces alces) in the autumn. Among the plant species investigated, Populus and Salix species were by far the most important Cd contributors. In areas where high Cd accumulators grow more widely, the daily Cd intake by moose could be as high as 7 mg or more.

Animals↗
PubMed2004

Further studies on the latitudinal and temporal trends of persistent organic pollutants in Norwegian and U.K. background air.

Data are presented for PBDEs, PCBs, and selected organochlorine compounds, measured at background locations by passive air samplers (semipermeable membrane devices, SPMDs) along a latitudinal transect from the south of the U.K. to the north of Norway during 2000-2002. This work is part of an ongoing air sampling campaign in which PCB data were previously obtained in 1994-1996 and 1998-2000. Comparisons of the masses of chemicals sequestered by the SPMDs during these different time intervals are used to investigate spatial and temporal trends. The study yielded examples of compounds that increase, decrease, or remain uniform with latitude, suggestive of differences in the relative importance of deposition versus atmospheric reaction in controlling their long-range atmospheric transport potential. The main constituents of the penta-BDE product were detected at amounts equivalent to 2.0 (range 1.1-2.5) and 1.1 (0.8-1.6) pg m(-3) for the U.K. and Norway background sites, respectively. Fractionation of PBDEs was observed, because the amounts of lighter BDEs decreased with latitude, while the heavier molecular weight congeners were quite uniformly distributed. In contrast, the sequestered amounts of the lighter PCBs were uniformly distributed with latitude, with heavier PCBs decreasing. Sequestered amounts of hexachlorobenzene increased with latitude. Preliminary PCB atmospheric clearance rates were derived using the 1994-1996, 1998-2000, and 2000-2002 data. They averaged ca. 3.5 years for all congeners/locations. No systematic differences in congeners or locations were noted, supporting the hypothesis that the underlying trends in European background air are still controlled by primary, rather than secondary, sources.

Air Pollutants↗
PubMed2004

PBDEs in European background soils: levels and factors controlling their distribution.

Surface soils (0-5 cm) from remote/rural woodland (coniferous and deciduous) and grassland locations on a latitudinal transectthrough the United Kingdom and Norway were analyzed for polybrominated diphenyl ethers (PBDEs). Concentrations ranged between 65 and 12 000 sigma(ALL)PBDE ng kg(-1) dry weight. PBDE-47, -99, -100, -153, and -154-the major constituents of the penta-BDE technical product-dominated the average congener pattern of the soils. Indeed, the average congener composition and distribution measured in these European background soils closely matched that reported in the technical penta-BDE product. This is interpreted as evidence that transfer of the congeners present in penta-BDE-treated products from source-air-soil occurs with broadly similar efficiency, perhaps because there has been little weathering/degradation/alteration of the congener source pattern by processes operating during atmospheric transport or within the soil itself. BDE-183, a marker for the octa-BDE mix, was detected at concentrations ranging from <9 to 7000 (median approximately 50 ng kg(-1)). In most soils, it made a minor contribution to the sigma(ALL)PBDE concentration, but it was a major component in some samples from northern England. Forest soils tended to have higher concentrations than grasslands. Underlying the average soil composition, some differences in the congener pattern were observed. Notably, there was evidence of latitudinal fractionation, with the relative contribution of PBDE-47 and lighter congeners to the sigmaPBDE increasing northwards (with increasing distance from source areas), while the proportion of PBDE-99 and heavier congeners decreased. Plots of concentration against percentage soil organic matter had different slopes for different congeners. Higher slopes were generally seen for the lighter PBDEs (e.g., PBDE-47), indicating that they have undergone some air-surface exchange (hopping), while the slopes of heavier congeners (e.g., PBDE-153) were close to zero, indicating that they are retained more effectively by soils after deposition.

Air Pollutants↗
PubMed2004

Globus pallidus: a target brain region for divalent metal accumulation associated with dietary iron deficiency.

Recently, iron deficiency has been connected with a heterogeneous accumulation of manganese in the rat brain. The striatum is particularly vulnerable, for there is a significant negative correlation between accumulated manganese and gamma-aminobutyric acid levels. The effect of dietary iron deficiency on the distribution of zinc and copper, two other divalent metals with essential neurobiological roles, is relatively unexplored. Thus, the primary goal of this study was to examine the effect of manipulating dietary iron and manganese levels on the concentrations of copper, iron, manganese and zinc in five rat brain regions as determined with inductively coupled plasma mass spectrometry analysis. Because divalent metal transporter has been implicated as a transporter of brain iron, manganese, and to a lesser extent zinc and copper, another goal of the study was to measure brain regional changes in transporter levels using Western blot analysis. As expected, there was a significant effect of iron deficiency (P < 0.05) on decreasing iron concentrations in the cerebellum and caudate putamen; and increasing manganese concentrations in caudate putamen, globus pallidus and substantia nigra. Furthermore, there was a significant effect of iron deficiency (P < 0.05) on increasing zinc concentration and a statistical trend (P = 0.08) toward iron deficiency-induced copper accumulation in the globus pallidus. Transporter protein in all five regions increased due to iron deficiency compared to control levels (P < 0.05); however, the globus pallidus and substantia nigra revealed the greatest increase. Therefore, the globus pallidus appears to be a target for divalent metal accumulation that is associated with dietary iron deficiency, potentially caused by increased transporter protein levels.

Animals↗
PubMed2003

Performance study of diffusive gradients in thin films for 55 elements.

The technique of diffusive gradients in thin films (DGT) is a fairly new and useful tool for in situ measurements of labile metal ions in water. The applicability of DGTs was investigated by comparing independently determined or estimated diffusion coefficients with DGT effective diffusion coefficients (D(DGT)) for 55 elements. The DGTs were exposed at a controlled fluid velocity of 0.1 m s(-1) and a concentration of 1 ng mL(-1) at four pH levels between 4.7 and 6.0, and the D(DGT) values were determined from the uptake by the sampler. The measured D(DGT) values for the elements Co, Ni, Cu, Zn, Cd, Pb, Al, Mn, and Ga were close to previously published values with some deviations for Pb and Zn. The uptake of V, Cr, Fe, U, Mo, Ti, Ba, and Sr varied with pH, and there were some experimental problems that require further investigations. A novel set of D(DGT) values for the lanthanides (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb, Yb, Lu, Y) was established. The D(DGT) values for these were about 10-15% lower than for free ions in water and indicate that diffusion coefficients of metal ions in the agarose polyacrylamide diffusive hydrogel are 10-15% lower than in water. The high consistency of the data for the lanthanides establishes these elements as new performance test metals for the DGT sampler. The accumulation of the elements Li, Na, K, Rb, Mg, Ca, B, Tl, P, S, As, Bi, Se, Si, Sn, Sb, Te, Zr, Nb, Hf, Ta, W, Th, and Ag was low (D(DGT) lower than 10% of theoretical values). A more efficient elution procedure using concentrated nitric acid for the absorbent gel was established, with elution efficiencies between 95 and 100% for most metals. For deployment times of 24 h, detection limits from 0.001 to 1 ng mL(-1) were achieved with moderate precautions to prevent contamination.

Journal Article↗
PubMed2003

Springtime depletion of mercury in the European Arctic as observed at Svalbard.

This study was carried out to see whether the geographical extent of the mercury depletion events (MDEs), first seen at Alert in the Canadian High Arctic, is also covering Svalbard. Another goal was to determine the main reaction products from the MDE and their fate. Gaseous elemental mercury (GEM), total particulate mercury (TPM), reactive gaseous mercury (RGM) and total mercury in surface snow have been measured at the Zeppelin mountain during 2000. GEM has been measured with a high time resolution automatic monitor (Tekran 2537A) based on CV-AFS, TPM was sampled/measured using high volume samplers/CV-AFS and RGM was sampled with annular denuders and measured by CV-AFS (Gardis Hg-monitor). During spring of 2000, in the three-month period following polar sunrise, there were several episodic depletions in GEM concentration correlating well with the depletion of surface ozone. Measurements of RGM and TPM showed higher concentrations of these mercury species during the depletion period than during the rest of the year. Total mercury in surface snow showed a distinct increase from the polar night to the Arctic spring. MDEs are caused by the specific chemical and physical conditions observed in the Arctic during spring. GEM is oxidised and converted to more reactive forms (RGM and/or TPM), which have considerably higher deposition velocities than elemental mercury, leading to an overall enhanced deposition flux of mercury.

Air Movements↗