1. |
- Peltola, Pasi, et al.
(författare)
-
Concentations and leachability of chemical elements in estuarine sulfur-rich sediments, W. Finland
- 2002
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 284:1-3, s. 109-122
-
Tidskriftsartikel (refereegranskat)abstract
- Concentrations, distributions and mobility of chemical elements were investigated in reduced sulfur-rich estuarine sediments located in western Finland. The main objective was to determine the possible extent of metal leaching when dredged masses of these sulfur-rich sediments are dumped on the land and thus exposed to air. When dredged, the reduced sulfur in the sediments oxidises resulting in a lowering of pH, which in turn is expected to leach metals. The study area is an artificial lake claimed from the Botnian sea in 1962. In this lake, several mass-kills of fish have occurred, believed partly to be due to dredging. Two sediment samples (0–50 and 50–100 cm) were taken from 39 sampling points in the lake. These samples were leached in aqua regia (2:2:2 HNO3/HCl/H2O) and analysed for Fe, Al, Mg, Ca, K, P, Na, Mn, Zn, Ba, V, Sr, Cr, Ni, Cu, Co, As, Pb, B, Mo and Cd with ICP-AES. Sulfur and organic carbon were analysed with Leco. In a controlled laboratory experiment, the sediments were allowed to oxidise for 1 year while moisturised with deionised water every month. The pH and conductivity were determined in the beginning of the experiment (reduced state) and in the end (oxidised state). In the supernatants in the oxidised states the amount of leached metals (Na, Al, Mn, Zn, Sr, Co, Ni, Cu, Cd, Cr, Pb, U, Li, Rb and As) were determined with ICP-MS. The sediments were found to contain low levels of toxic metals but, as expected, high concentrations of sulfur. In the experiment, pH was lowered (down to 3.0) and the conductivity increased in all samples due to oxidation and release of metal ions. The extent of leaching varied between 0.03% for As and 12.3% for Na. Critical pH values, at which high amounts of metals begin to leach, were obtained graphically. These values varied between 4.8 (Ni) and 3.3 (Cr). Not all elements were controlled by pH, e.g. Mn correlated well with its aqua regia leachable concentration. In a planned dredging operation in the area some 23 300 t (10 500 m3) (dry wt.) of sediments will be dredged. The amounts of metals likely to be leached, according to the results from this study, are as follows (kg): Al (1710), Mn (1230), Zn (59), Sr (39), Co (13), Ni (12), Cu (2) and less than 1 kg of Cd–Cr–As–Pb.
|
|
2. |
- Andren, P, et al.
(författare)
-
Environmental exposure to lead and arsenic among children living near a glassworks
- 1988
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 1879-1026 .- 0048-9697. ; 77:1, s. 25-34
-
Tidskriftsartikel (refereegranskat)abstract
- Concentrations of lead (Pb) in blood (B-Pb, geometric mean 34.6 micrograms l-1, n = 127) and inorganic arsenic (As) and its metabolites in urine (U-As, mean 5.1 micrograms/g creatinine, n = 35) did not differ between children living in a village close to a glassworks emitting both Pb and As and children living in a reference area. There was no significant effect on B-Pb and U-As related to parents working at the glassworks or consumption of domestically grown vegetables. Neither was there any significant effect upon B-Pb of sex, age, potentially lead-exposing hobbies, or consumption of canned foods. Boys had higher U-As than girls (5.8 vs 4.2 micrograms/g creatinine, p = 0.005), and there was a decrease with age (range 8.4-10.4 years, 27% per year, p = 0.01). Further, parental smoking habits had a significant effect on both B-Pb and U-As. In children of non-smoking parents the B-Pb was 30 micrograms l-1, in children with one parent who smoked 39 micrograms l-1 (smoking father 37, smoking mother 41 micrograms l-1) and in children with two parents who smoked 47 micrograms l-1 (p less than 0.001). The corresponding values for U-As were 4.2, 5.5, and 13 micrograms/g creatinine, respectively (p = 0.01).
|
|
3. |
- Barany, E, et al.
(författare)
-
Trace element levels in whole blood and serum from Swedish adolescents
- 2002
-
Ingår i: Science of the Total Environment. - 1879-1026 .- 0048-9697. ; 286:1-3, s. 129-141
-
Tidskriftsartikel (refereegranskat)abstract
- Blood and serum samples from 372 15-year-old adolescents were collected in two cities in Sweden and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The objective was to (1) determine the levels of 13 elements in blood and serum from the teenagers; and (2) for each element, investigate the correlation between the concentrations in blood and serum. The concentrations in blood and serum were generally in line with that usually reported for the essential elements Co, Cu, Zn and Se, and generally low for the 'non-essential' elements Cd, Hg, Pb. The median concentrations were in blood and serum, respectively: of Co 031 and 0.48 mug/l, Cu 0.92 and 1.0 mg/l, Zn 6.1 and 0.99 mg/l, Se 110 and 100 mug/l, Rb 2.8 and 0.24 mg/l, Hg 1.1 and 0.44 mug/l, Pb 16 and 0.33 mug/l. The median concentration of W in blood was < 0.2 mug/l (below the detection limit) and in serum 0.087 mug/l. The median concentrations of Cd, Rh, Pd, Pt and TI were below the detection limits. Statistically significant correlations were found between the concentrations in blood and serum for Co, Cu, Zn, Se, Rb, W, Hg and Pb. The levels presented in this study constitute baseline levels or levels generally not exceeded in adolescents for 13 elements, including essential, ubiquitous toxic, and rare elements.
|
|
4. |
- Eriksson, E., et al.
(författare)
-
Life cycle assessment of the road transport sector
- 1996
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 189-190, s. 69-76
-
Tidskriftsartikel (refereegranskat)abstract
- The road transport sector has been studied with a life-cycle perspective. Transport activities and products used for road transportation have been analysed in order to identify those with significant contribution to the total environmental impact. Detailed data on the environmental burdens caused by different transportation activities such as fuel production, fuel combustion at driving, maintenance of the vehicle and production and after use treatment of the vehicle have been collected and transformed into a form usable in life cycle assessment (LCA). A comprehensive and flexible system model for description of road transportation systems has been developed. A software program, KRABAT, has been developed from the system model. The program has been used for calculation of the environmental burdens of road transportation. The use of non-renewable energy is sometimes used as an indicator of the environmental impact of activities. In this study the consumption of non-renewable fuels, electricity and air emissions have been considered. The production, maintenance and after use treatment of the vehicle have shown to contribute significantly to the total environmental impact of road transportation, measured per vehicle kilometer. This is especially valid for passenger cars, for which the amount of fossile fuel used for production of the vehicle is about 10% of the total amount used during the whole life time of the car. This share is generally much smaller for trucks, since they are used more frequently than passenger cars. The treatment of the different materials of the car after use is of importance for the possibilities of minimization of the environmental impact from road transport. In a case study, the environmental burdens from all processes and transports in the life cycle of newspapers have been analysed. Two after use treatment scenarios were studied, one with 70% recycling and the other with 100% incineration with heat recovery. The total contribution of environmental burdens from transportation to the total of the whole life cycle were studied. It could not be concluded that transportation increased with a higher degree of recycling. This holds true for our assumptions. The result may however be different for other geographical conditions, population densities, etc.
|
|
5. |
- Österberg, Kai, et al.
(författare)
-
A neurobehavioural study of long-term occupational inorganic lead exposure
- 1997
-
Ingår i: Science of the Total Environment. - 0048-9697. ; 201:1, s. 39-51
-
Tidskriftsartikel (refereegranskat)abstract
- A group of 38 male workers at a secondary smelter (period of employment 2-35 years; median 10 years) was divided into two subgroups depending on bone-lead concentration, arranged as 19 matched pairs according to age, education and job level. The median concentrations for finger-bone lead (Bone-Pb) were 16 vs. 32 μg/g; for current blood-lead (B-Pb), 1.6 vs. 1.8 μmol/l; for retrospective peak blood-lead (Peak-Pb), 2.7 vs. 3.0 μmol/l; and for a retrospective cumulative blood lead index (CBLI), 143 vs. 233 μmol/l x months. Nineteen unexposed male workers from a nearby mechanical plant served as controls, using the same matching algorithm. The triplets were examined with a standardised neuropsychological test battery, and four questionnaires for self-rating of symptoms and activity/stress level related to work environment. No sign of behavioural deterioration was observed in the exposed groups, either in objective cognitive tests or in subjective symptom/mood self-rating scales. Despite the limited sample size, the statistical power was sufficient to conclude that a concealed lead-associated effect was unlikely. Covariations between behavioural measures and lead exposure indices were generally low and non-significant, as a whole not exceeding a random level. No confounding or effect-modifying factor was detected that could explain the results as a type II error. To conclude, a current B-Pb of 1.8 μmol/l was not associated with adverse behavioural effects, and a long-term lead exposure around 2.0 μmol/l for 13 years (mean values) was not associated with permanent brain dysfunction.
|
|
6. |
- Ahlborg, UG
(författare)
-
Methods of risk assessment
- 1996
-
Ingår i: The Science of the total environment. - : Elsevier BV. - 0048-9697. ; 188188 Suppl 1, s. S75-S77
-
Tidskriftsartikel (refereegranskat)
|
|
7. |
- Bhattacharya, Prosun, et al.
(författare)
-
Metal contamination at a wood preservation site : characterisation and experimental studies on remediation
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 290:03-jan, s. 165-180
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this investigation was to determine the occurrence of As, Cu, Cr and Zn in the soil at an abandoned wood preservation unit and to examine some possible extractants for the contaminants in the soil. The mean As content of the contaminated surface soils (0-10 cm) was 186 mg kg(-1), where as the mean concentrations of Cu, Cr and Zn in soils from the contaminated area were 26, 29 and 91 mg kg(-1), respectively. The elevated As content in the mineral soils is related to adsorption of inorganic As phases in the fine grained fractions, which are characterised by large surface area and high positive surface charge under the current acidic conditions. Cu and Cr were found to be rather mobile, which is reflected in their lower abundance in soils and significant accumulation in sediments in the drainage leaving the area. The fine fraction of the soil (<0.125 mm) has an average metal content increased by nearly 34% as compared to the <2-mm fraction conventionally used for the analysis and assessment of soil contamination. The <2-mm fraction constitutes approximately 65% of the total weight while the fine fraction (< 0.125 mm) constitutes approximately 10%. These facts, taken together, are essential for the choice of remediation measures. Oxalate solutions have been tested as extractants for soil remediation. Dark acid oxalate extraction dissolves the amorphous Al- and Fe-oxides and hydroxides and mobilises the adsorbed inorganic As species. Oxalate also acts as a ligand for the cationic heavy metals, releasing them from exchangeable sites. With a three-step sequential leaching, up to 98-99% of the metals could be removed. At lower concentrations and higher pH, the leaching decreased to approximately 70%.
|
|
8. |
- Bozkurt, S., et al.
(författare)
-
Long-term processes in waste deposits
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 250:03-jan, s. 101-121
-
Tidskriftsartikel (refereegranskat)abstract
- A conceptual model, which is a unitary and continuous description of the overall processes in waste deposits, has been developed. In the model the most important processes governing the long-term fate of organic matter in landfills and the transport and retention of toxic metals are included. With the model as a base, a number of scenarios with different levels of complexity have been defined and studied in order to carry out long-term assessments of the chemical evolution in waste deposits for industrial and municipal solid waste containing much organic matter and the leaching of toxic metals. The focus of the modelling has been to quantify the important processes occurring after the methane production phase has ceased, i.e. during the humic phase. The scenarios include the main mechanisms based on various transport processes as well as different landfill constructions, e.g. binding capacities of sulfides and humic substances. They also include transport mechanisms by which the reactant oxygen can intrude into a deposit, sorption capacities of hydrous ferric oxides, and pH-buffering reactions, etc. Scoping calculations have shown that the binding capacity of humic substances is sufficient to bind all toxic metals (Cd, Cr, Pb, Zn and Hg). In addition, the humics could also bind a smaller part of Ca, Fe and Al, provided much of the organic waste remain as humic substances. Sulfides on the other hand can bind approximately twice the amount of all toxic metals. The binding capacity of hydrous ferric oxides, which can be formed by oxidation reactions during the humic phase, is estimated to be three times the total content of metals that can sorb on hydrous ferric oxides. In the studied landfill the pi-I-buffering capacity, primarily represented by calcite, is estimated to be 1 mol/kg dry waste. Quantifications indicate that the alkalinity of the wastes is high enough to buffer the acidity produced by the oxidation of sulfides and by the degradation of organic matter, as well as that added by acid precipitation. Therefore, the main conclusion is that higher remobilisation rates of heavy metals due to lowering of pH are not expected for many thousands of years.
|
|
9. |
- Bozkurt, S., et al.
(författare)
-
The long-term evolution of and transport processes in a self-sustained final cover on waste deposits
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 271:03-jan, s. 145-168
-
Tidskriftsartikel (refereegranskat)abstract
- A new principle for confinement of waste based on a self-sustained seal is presented. The top cover is considered to consist of two main layers; an organic carbon rich surface layer that is able to support vegetation and an inorganic layer beneath it. The function of the cover is to mitigate oxidation and acidification of landfilled waste and hence the release of toxic metals. It is suggested that forest soil formation and soil development could prove to be valuable information sources for the study of the long-term behaviour of a final cover on waste deposits. Since the cover is expected to develop in northern temperate climate the focus is on Spodosol soil. A number of simulations of the long-term behaviour of the final self-sustained landfill cover are made, including the rates of influx of oxygen into the cover. A cover having a large portion of organic matter compared with a cover with no organics can considerably decrease the oxygen concentration and thus the influx of oxygen into a landfill. The calculated oxygen intrusion rate for the former case is of the order of 0.05 kg m(-2) year(-1). Degradation of the organics produces acids. Our simulations indicate that the pH-buffering capacity of the mineral layer, represented by calcite and primary rock minerals, will last for many thousands of years.
|
|
10. |
- Bratt, P, et al.
(författare)
-
Function of the rat salivary glands after exposure to inorganic mercury
- 1995
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 172:1, s. 47-55
-
Tidskriftsartikel (refereegranskat)abstract
- In spite of many studies on the toxicity of mercury, very little is known about the effects of mercury on the function of exocrine glands. In the present paper selected functions of Sprague-Dawley rat salivary glands were studied after the exposure of the animals to inorganic mercury at two different doses; 3.25 mg/kg body weight given during 25 days and 7.0 mg/kg body weight given during 27 days. The function of the salivary glands was estimated by saliva secretion rate, secretion of electrolytes, proteins and biosynthesis of glycoproteins. The function was compared between mercury exposed rats and age and sex matched control rats that were given injections with equal volumes of 0.154 mol/l NaCl on the same time schedule. In the present study we report that no significant effect on saliva secretion rate, concentrations of salivary constituents or biosynthesis of glycoproteins in the salivary glands could be observed in rats as a result of mercury exposure at two levels that gave 30 or 60 times higher serum mercury concentrations than in the majority of the Swedish population.
|
|
11. |
- Bucksch, S., et al.
(författare)
-
The Swedish program for investigations concerning biofuels
- 1999
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 235:1-3, s. 293-303
-
Tidskriftsartikel (refereegranskat)abstract
- As constituted today, the transport sector is not sustainable in the long-term. It is based almost entirely on non-replenishable natural resources which, when combusted, release emissions that can cause serious harm to human beings, animals and the natural environment. Therefore, in order to achieve a sustainable transport system, it is imperative to achieve a means of propulsion, which is based on renewable energy sources in every phase of production and distribution. The responsibility for developing such a sustainable transport system is an assignment, which must be approached as a common cause, involving both the official agencies of society and the business sector together with international cooperation. In 1991 the Swedish Government allocated 120 million Swedish crowns to the Swedish Transport and Communications Research Board (KFB) as funds for research, development and demonstration in the field of biofuels to be used in the transportation sector. In order to fulfil this obligation a program was presented and approved and this program for engine alcohols and biogas was carried out between the summer of 1991 and the end of 1997. The program has generated a broad spectrum of useful results showing that, in general terms, there are a number of technical problems connected to the use of biofuels. There is also a need to continue the development of both the fuels and the engines in order to take advantage of all that can be achieved concerning the use of biofuels in the transportation sector. The presentation at The Sixth International Highway and Urban Pollution Symposium will focus on a brief description of the program carried out and a presentation of the results of the field tests and the emission characterisation.
|
|
12. |
- Bäckström, Mattias, 1974-, et al.
(författare)
-
Effects of a fulvic acid on the adsorption of mercury and cadmium on goethite
- 2003
-
Ingår i: Science of the Total Environment. - Amsterdam, Netherlands : Elsevier. - 0048-9697 .- 1879-1026. ; 304:1-3, s. 257-268
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of an aquatic fulvic acid on the pH-dependent adsorption of Hg(II) and Cd(II) to particulate goethite (a-FeOOH) were studied in batch systems. The ionic medium consisted of 0.01 M HClO and the total concentrations 4 of mercury and cadmium were maintained at 10y8 M with 203Hg and 109Cd as tracers. pH In the systems was varied in the range 3–10 by addition of HClO and NaOH.All commercial chemicals were of analytical grade or better. An 4 aquatic fulvic acid (20 ppm), previously isolated and characterised in detail, was used as a model for humic substances and its adsorption to goethite is included in this study. The adsorption of the fulvic acid (20 ppm) onto goethite decreased slowly from 90% at pH 3–7.5 to 10% at pH 10. In systems without fulvic acid the adsorption of mercury increased in a linear fashion from 10% at pH 3 to 70% at pH 10.In the presence of fulvic acid (20 ppm), the adsorption was almost quantitative in the intermediate pH range (pH 5–7), and exceeded 92% over the entire pH range. Thus, association between mercury and the fulvic acid enhanced adsorption in general although the largest impact was found at low pH.Adsorption of cadmium increased from nearly 0 to almost 100% at approximately pH 6. In the presence of fulvic acid, the adsorption increased below pH 7 and decreased above pH 7. The adsorption isotherm for mercury when the concentration was increased from 10y8 to 1.8=10y4 M showed a corresponding increase of K (lyg) up to a total concentration at 10y6 M.At higher mercury concentrations K was lowered. In the presence of fulvic acid the corresponding relationship of K was bi-modal, i.e. high values at low and intermediate concentrations of mercury. This behaviour suggests that in the absence of fulvic acid the adsorption follow the expected behaviour, i.e. adsorption sites with similar affinity for mercury. In the presence of fulvic acid, additional adsorption sites are available by the organic molecule (possibly sulfur groups) when it is associated to the goethite. The adsorption isotherm for cadmium indicates a lowering of K at 10y4 M. Cadmium had no competitive effect on mercury and vice versa. Zinc, however, affected the adsorption of cadmium but not the adsorption of mercury.
|
|
13. |
- Carlsson, E., et al.
(författare)
-
Sequential extraction of sulfide-rich tailings remediated by the application of till cover, Kristineberg mine, northern Sweden
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 299:1-3, s. 207-226
-
Tidskriftsartikel (refereegranskat)abstract
- A sequential extraction has been carried out on sulfide-rich mine tailings. The purpose was to investigate how elements released by oxidation are secondarily retained in the tailings and the possible consequences of the remediation. After investigating the solid tailings, seven samples were chosen for sequential extractions. Two samples were oxidised, situated just above the oxidation front, two samples from just below the former oxidation front with increased concentrations of several elements, two unoxidised samples were from an intermediate depth, and the deepest sample was from the tailings-peat boundary at the bottom of the impoundment. Five phases were extracted: adsorbed/exchangeable/carbonate, labile organics, amorphous Fe-oxyhydroxides/Mn-oxides, crystalline Fe-oxides, and organics/sulfides. The addition from dried porewater to the extracted fractions has been calculated and considered as minor. In the oxidised tailings, the sulfide fraction still dominates for elements such as Fe, S, Cd, Co, Cu, Hg and Zn, although the concentrations are low compared to the unoxidised tailings. Generally, the second most important fraction is the adsorbed/exchangeable/carbonate fraction. Below the oxidation front, the sulfide content of the tailings sharply increases. In the secondary enrichment zone, the total element concentrations increase compared with the deeper unoxidised samples, mainly due to secondary retention. For some elements, secondary retention is greater than the total amount extracted for the deeper unoxidised samples. In the secondary enrichment zone the adsorbed/exchangeable/carbonate fraction represents approximately 20 wt.% or more for Cd, Co, Mn, Ni and Zn. The amorphous iron oxyhydroxide or the crystalline iron oxide fractions are less important at this level, although for As, Ba and Cu the amorphous iron oxyhydroxide fraction represents up to 20 wt.%. At the lower border of the enrichment zone, the total concentration for most metals is lower, but the importance of the adsorbed/exchangeable/carbonate fraction is further enhanced for Cd, Cu, Ni and Zn. These elements have 35-60 wt.% of the total amount from this fraction. For As, Cd, Cu, Ni and Pb, the secondary fractions extracted (extractions A-D) represent between 60 and 80 wt.% of the total content. At greater depth in the impoundment the relative importance of the adsorbed/exchangeable/carbonate fraction decreases, whilst the importance of amorphous iron oxyhydroxide and crystalline iron oxide fractions increases. The adsorbed/exchangeable/carbonate fraction is the most easily remobilised fraction. A raised groundwater table previously situated below the enrichment zone may result in the release of secondarily retained metals. © 2002 Elsevier Science B.V. All rights reserved.
|
|
14. |
|
|
15. |
- Danilov, Roman, et al.
(författare)
-
The use of epiphyton and epilithon data as a base for calculating ecological indices in monitoring of eutrophication in lakes in central Sweden
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 248, s. 63-70
-
Tidskriftsartikel (refereegranskat)abstract
- Eutrophication was monitored with the aid of one similarity and seven diversity indices in the lakes of different trophic levels (eutrophic, mesotrophic and oligotrophic) in central Sweden. The ecological indices were applied separately to epiphyton and epilithon communities. Epiphyton turned out to be inappropriate for assessing eutrophication in the lakes studied. On the other hand, Hurlbert's, Simpson's and the similarity indices turned out to be promising environmental tools when applied to the data of epilithon.
|
|
16. |
|
|
17. |
- Engwall, Magnus, 1965-, et al.
(författare)
-
Fate of Ah-receptor agonists in organic household waste during anaerobic degradation : estimation of levels using EROD induction in organ cultures of chick embryo livers
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 297:1-3, s. 105-108
-
Tidskriftsartikel (refereegranskat)abstract
- The fate of 7-ethoxyresorufin O-deethylase (EROD)-inducing compounds in source-separated organic household waste subject to anaerobic degradation (i.e. mesophilic/thermophilic anaerobic treatment) was investigated using organ cultures of embryonic chicken livers from fertilised hen eggs. This bioassay reflects the combined effect of all EROD-inducing, possibly dioxin-like compounds in a sample, including chemicals that are seldom or never analysed. All samples tested induced EROD in the bioassay, indicating the presence of dioxin-like compounds. In the anaerobic processes, the amounts of acid-resistant EROD-inducing compounds coming out of the reactors were considerably higher than the incoming amounts, especially for the low-temperature (mesophilic) process. This apparent production of EROD-inducing compounds may be due to de novo synthesis or to an increase in the EROD-inducing potency of the compounds in the material.
|
|
18. |
|
|
19. |
- Flink, P, et al.
(författare)
-
Statistical analysis of hyperspectral data from two Swedish lakes
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 268:1-3, s. 155-169
-
Tidskriftsartikel (refereegranskat)abstract
- CASI data has been collected from two lakes in Sweden. In this paper. some statistical properties of CASI spectral data have been discussed. Principal component analysis is used for assessing the dimensionality of the data and the principal components wer
|
|
20. |
|
|
21. |
|
|
22. |
- Funseth, Eva, et al.
(författare)
-
Effects of coxsackievirus B3 infection on the acute-phase protein metallothionein and on cytochrome P-4501A1 involved in the detoxification processes of TCDD in the mouse
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 284:1-3, s. 37-47
-
Tidskriftsartikel (refereegranskat)abstract
- During acute infections, the synthesis of acute-phase proteins and other proteins participating in the host defence are stimulated in the liver and kidney. In previous studies of coxsackievirus B3 (CB3) infection in mice, we found that cadmium (Cd) accumulates in the kidney, whereas 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) accumulates in the liver. To study if CB3 infection affects the synthesis of the Cd-binding protein metallothionein (MT) and the TCDD-binding/detoxifying cytochrome P-450 (CYP-450) isozyme CYP1A1, the basal and TCDD-induced levels of serum MT and liver CYP1A1 isozyme were determined in healthy and CB3-infected A/J mice. Furthermore, because interferons affect CYP450 activity, the serum levels of the interferons alpha (IFN-alpha) and -beta (IFN-beta) were measured in CB3-infected mice and in mice treated with the interferon-inducer polyinosinic/polycytidylic acid (poly I/C). Virus or poly I/C was administered intraperitoneally (i.p.) on day 0 and 500 ng TCDD/kg bodyweight on day 1. On day 4, CB3 infection had induced MT approximately 10-fold, regardless of TCDD treatment (P < 0.01 in infected mice and P < 0.001 in infected, TCDD-treated mice). TCDD alone induced a 10-fold increase in CYP1A1 activity (P < 0.001), whereas infection alone suppressed the normal CYP1A1 activity by 75% (P < 0.001). Infection also suppressed the TCDD-induced CYP1A1 activity by approximately 30% (n.s.). Poly I/C suppressed CYP1A1 by 20-25% (n.s.) at both basal and TCDD-induced levels. Serum IFN-alpha and IFN-beta levels were undetectable in controls, in TCDD-treated and in the poly I/C-treated groups on day 4, probably because the short IFN peak is detectable only hours after injection. Conversely, on day 4 of the infection, IFN-alpha and IFN-beta were consistently raised in the TCDD-treated infected mice, whereas increased IFNs as a result of infection alone could be detected in only one individual. These results suggest that the normal host responses during acute infections down-regulate detoxifying processes in favour of acute-phase protein synthesis. This may explain the observed changed pattern of accumulation, excretion and toxicity of the environmental pollutants cadmium and TCDD during this common virus infection.
|
|
23. |
- Färm, Carina
(författare)
-
Metal Sorption to Natural Filter Substrates for Storm Water Treatment - Column Studies
- 2002
-
Ingår i: The Science of the Total Environment. - 0048-9697. ; 298:1-3, s. 17-24
-
Tidskriftsartikel (refereegranskat)abstract
- Storm water generated from road runoff contains pollutants such as metals that are either dissolved in storm water or bound to particulates. Using detention ponds for the treatment of storm water from road runoff, where particles can settle, can reduce the level of particulate-bound metals in the water, while small particles and dissolved matter pass through the detention pond. Some of these metals can be removed by filtrating water through specially constructed filter systems. This investigation is a laboratory study where different filter substrates were tested in order to evaluate their efficiency in reducing heavy metals from water. Metal solutions were filtered through columns filled with various substrates consisting of combinations of calcium silicate rock (opoka), zeolite and peat. The metal-removal efficiency was correlated to hydraulic load, and for the metal species the reduction efficiency decreased with increased hydraulic load. Mixtures of opoka and zeolite were found to be superior to the other filter-substrate combinations tested with regard to both hydraulic aspects and removal efficiency. Peat mixed with the calcium silicate rock was not successful due to clogging which stopped the experiment. A manufactured product made from the calcium silicate rock (burned opoka) was found to be less useful because of its calcium oxide (CaO) content. Among the tested filter substrates, mixtures of opoka and zeolite seemed to be the most useful compositions with respect to reduction-efficiency and clogging aspects. The removal capacity of metals varied from 0.6 to 1.8 kg m(-3) depending on the metal and the filter substrate.
|
|
24. |
|
|
25. |
- Holmström, Henning, et al.
(författare)
-
Geochemical investigations of sulfide-bearing tailings at Kristineberg, northern Sweden, a few years after remediation
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 273:1-3, s. 111-113
-
Tidskriftsartikel (refereegranskat)abstract
- In the Kristineberg mining area in northern Sweden, massive, pyrite-rich Zn-Cu ores are intercalated in ca. 1.9 Ga volcano-sedimentary rocks. Investigations of a tailings impoundment remediated by means of both till coverage and raising the groundwater table have been undertaken. The aim of the study was to characterise the tailings with respect to mineralogy, the chemical composition of both the tailings and the pore water, and to try to identify the significant reactions that may have occurred before and after remediation. It was found that the oxidation front had reached down to depths of between approximately 0.1 and 1.15 m before remediation. The oxidation of sulfides has produced high concentrations of some metals in the pore water; up to 26, 16, 4.1, 2.7 and 82 mg/l have been measured for Al, Mn, Fe and Zn, respectively. Concentrations of metals such as Cd, Co, Cu, Ni and Pb are lower, with average concentrations of 18.4, 83.8, 45, 79.6 and 451 μg/l, respectively. Higher concentrations of major elements such as Ca, Fe, Mn, Mg and S have been measured at depth in pore water than at shallower levels. This is probably caused by flush out of elements after remediation and vertical transport from the upper parts before remediation. The pH is relatively high, approximately 5.5 at most depths in the tailings, except in and around the former oxidation zone where it is lower, and where the highest dissolved concentrations of elements such as As, Cd, Co, Cu, Pb and Zn occur. This is probably due to the release of metals secondarily retained below the oxidation front prior to the remediation. Since the groundwater table is raised, the groundwater reaches the retained metals, which leads to desorption of metals and dissolution of secondary minerals.
|
|
26. |
- Holmström, Henning, et al.
(författare)
-
The character of the suspended and dissolved phases in the water cover of the flooded mine tailings at Stekenjokk, northern Sweden
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 247:1, s. 15-31
-
Tidskriftsartikel (refereegranskat)abstract
- Studies of the suspended and dissolved phases of the pond water, material collected from sediment traps, and surficial sediments/tailings from the flooded tailings pond at Stekenjokk have been performed. The aim was to characterise the material, to study the seasonal variations and to quantify possible resuspension of the tailings in the pond. The element concentrations in the pond at Stekenjokk seem to be largely controlled by processes controlling the precipitation and dissolution of Mn- and Fe-oxyhydroxides in both the water column and in the surficial tailings. Physiochemical processes such as weathering of silicates on the surrounding mountain slopes or dykes contributes both dissolved elements and detrital particles. The suspended phase consists of detrital silicate material as well as Fe- and Mn-oxyhydroxides. The average heavy metal concentrations are high, e.g. 0.42% Cu, 0.15% Pb and 3.1% Zn, which is probably due to sorption onto Fe- and Mn-oxyhydroxides. The suspended phase is richer in Fe, and particularly Mn, during the winter. The suspended phase resembles the material collected in sediment traps and the material in the surficial sediments. The pond water is well mixed during the ice-free season. The dissolved heavy metal concentrations are generally rather low with, e.g. maximum concentrations of 2.03 μg/l Cu, 0.23 μg/l Pb and 268 μg/l Zn during the winter. Higher dissolved concentrations are found below the ice-cover above the sediment surface during the winter, caused by diffusion of elements from the sediment-water interface up into the pond water. Most of the metals occurring in the pond are dissolved and resuspension of tailings is negligible.
|
|
27. |
- Hynes, M.J., et al.
(författare)
-
Element migration from glass compositions containing no added lead
- 2004
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 319:1, s. 39-52
-
Tidskriftsartikel (refereegranskat)abstract
- Six crystal glass compositions without added lead were used to prepare standard beakers having a volume of ca. 240 ml. The experimentally determined concentrations of the elements in the glass beakers were in satisfactory agreement with the theoretically predicted values. The degree of leaching of selected elements from these beakers was determined using 4% acetic acid as described in the ISO 7086-1:2000 standard test. In addition, to the degree of leaching by 4% acetic acid, migration into cola, red wine, 40% ethanol and 0.3% citric acid was also determined. Elements tested included antimony, barium, bismuth and zinc as these were considered to be of most interest. The results show that it is possible to produce durable glass containing no added lead. The overall quality of the glasses was good and the concentrations of the various elements migrating (leaching) into the various test solutions used was very small and it is clear that they would not present a hazard to consumers in the event that they were to use glasses of any of these compositions for consumption of either alcoholic or non-alcoholic beverages. The original ISO7086-1:2000 test using a 4% acetic acid leaching solution was developed to test for lead migration from crystal containing added lead and ceramic ware containing lead glazes or colouring. This work also shows that it is an excellent leaching agent for assessing the safety of crystal containing no added lead as it gave the highest degree of migration for all the glass compositions and all the elements tested. In the case of glasses containing ZnO, it was shown that the degree of zinc migration was linearly related to the mole-% of ZnO in the glass. With respect to the durability of glasses, it was shown that the degree of attack increases when the degree of silica depolymerisation increases. © 2003 Elsevier B.V. All rights reserved.
|
|
28. |
- Johansson, H., et al.
(författare)
-
Retention of conservative and sorptive solutes in streams - simultaneous tracer experiments
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 266:03-jan, s. 229-238
-
Tidskriftsartikel (refereegranskat)abstract
- The effective transport velocity of solutes in rivers and streams is governed by transient storage in hyporheic zones in which the longitudinal advection velocity is small relative to the main stream flow velocity. Results from a simultaneous tracer experiment using a non-reactive (tritium, (H2O)-H-3) and a sorptive tracer [chromium, Cr-51(III)] have formed the basis of a more accurate interpretation of the retention characteristics of solutes in streams than previously has been possible. By using a simultaneous injection of these two tracers, it was possible to distinguish between their different behaviours. Based on estimations of fluxes, the retained mass of chromium in the storage zones along the 30-km-long study-reach was 76% after 150 h. Independent observations in the bed sediment indicated that the loss of chromium observed in the water was mainly a result of uptake into the bed sediment. To describe the transport in the stream, a model concept including solute sorption kinetics in the bed sediment was proposed. Evaluation of parameters in the model, indicated that the uptake of chromium in the bed sediment is controlled by sorption kinetics.
|
|
29. |
- Johansson, Inger, et al.
(författare)
-
Levels and patterns of polycyclic aromatic hydrocarbons in incineration ashes
- 2003
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 311:1-3, s. 221-231
-
Tidskriftsartikel (refereegranskat)abstract
- Polycyclic aromatic hydrocarbons were analysed in weathered bottom ash from municipal solid waste incineration, fly ash from a mixed heating plant and an ash mixture from different kinds of biofuels. Although of different origin and age, all three ashes are evaluated in different small-scale fill applications. The ultimate goal is the usage of these ashes on a larger scale. The samples were Soxhlet extracted and analysed using GC/MS in the full scan mode. The sum of the 16 US EPA PAHs was found to vary from 140 mug/kg up to more than 77 000 mug/kg. Total amounts of PAHs were similar in bottom ash and in fly ash. The concentration in the mixed biofuel ash was more than 10 times higher, and exceeded the generic guidelines for PAHs in soil set by the Swedish Environmental Protection Agency. The patterns of the individual PAHs normalised to the total concentration of PAHs were found to be very similar for all the three ashes. Naphthalene and phenanthrene were the dominating PAHs for all ash samples, but the mixed biofuel ash also contained high levels of fluoranthene and pyrene. (C) 2003 Elsevier Science B.V. All rights reserved.
|
|
30. |
- Johansson, Lena, 1967-
(författare)
-
Blast furnace slag as phosphorus sorbents - column studies
- 1999
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 229:1-2, s. 89-97
-
Tidskriftsartikel (refereegranskat)abstract
- Filter substrates that efficiently remove phosphorus (P) from wastewater can be used to optimise the nutrient removal by on-site wastewater treatment systems. A number of filter substrates have been investigated and the industrial by-product blast furnace slag has attracted attention as a promising substrate. To further evaluate the sorption and attenuation of PO(4)(3-), a column experiment was carried out under conditions of intermittent P loading. Two types of slag were used; crystalline slag (CS) and amorphous slag (AS). The slags were available in two particle sizes; 0-0.125 mm and 0.25-4 mm, respectively. The slags were mixed with inert sand to improve the hydraulic conductivity. In addition to the column experiment, a P fractionation experiment was conducted. The sorption experiment indicated that the removal of P by the CS (0.25-4 mm), the AS (0.25-4 mm) and the AS (0-0.125 mm) columns at the end of the experiment exceeded 95%. In the other columns, the P sorption had decreased remarkably indicating a beginning saturation of the substrates. The P fractionation experiment showed that the P sorption was largest in the uppermost layers. Clear gradients of the P sorption in the downward direction could also be observed. It was concluded that the P sorption by the coarser slags was high at the end of the experiment indicating that saturation had not been achieved.
|
|
31. |
- Johansson Thunqvist, Eva-Lotta, et al.
(författare)
-
Airborne spreading and deposition of de-icing salt : A case study
- 1999
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 235:1-3, s. 161-168
-
Tidskriftsartikel (refereegranskat)abstract
- In this study it was concluded that between 20 and 63% of the de-icing salt applied on the road was transported by air and deposited on the ground 2-40 m from the road. The reason for the higher percentages is suggested to be intense snowfall, which leads to more splash generation and ploughing. Ninety percent or more of the total deposition occurs within 20 m at all transects. For all periods and both localities the deposition was greater on the east side of the road, which reflects the prevailing westerly winds in relation to the de-icing action occasions.
|
|
32. |
- Jonsson, Arne, et al.
(författare)
-
Phasing out cadmium and lead : Emissions and sediment loads in an urban area
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 292:1-2, s. 91-100
-
Tidskriftsartikel (refereegranskat)abstract
- This paper examines how fluxes in the aquatic environment reflect the reduced use of cadmium (Cd) and lead (Pb) in Stockholm, Sweden, between 1975 and 1995. The sediment deposition of Cd and Pb in the waters around Stockholm was investigated using laminated sediment cores, which facilitated reconstructions of historical annual metal deposition to the sediments. The resulting reconstructions were compared to independent estimations of the emissions to the aquatic environment during the phase-out period. The loads of Cd and Pb from sewage treatment plants, storm water and in atmospheric deposition were studied using literature data. The data set indicates a reduced load of Cd and Pb on the aquatic surroundings of Stockholm. The reduction is, however, not as pronounced in the sediment deposition as in the calculated emissions. This indicates that emissions may be delayed on their way to the sediments or that there are other sources, e.g. resuspension of older sediments. It is therefore argued that sediment investigations are an essential component in environmental monitoring, in order to get a complete picture of the metal fluxes to and in the environment in urban areas. © 2002 Elsevier Science B.V. All rights reserved.
|
|
33. |
- Jonsson, K., et al.
(författare)
-
Effect of sorption kinetics on the transport of solutes in streams
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 266:03-jan, s. 239-247
-
Tidskriftsartikel (refereegranskat)abstract
- To provide an appropriate description of the transport of a reactive substance in a stream, it is important to include a kinetic description of sorption in a transport model. In this study, first-order sorption kinetics was taken into account in both the transient storage zone and the stream water, and analytical expressions for relative error in statistical moments of the residence time PDF, resulting from disregarding sorption kinetics, were derived. The sorption rate coefficient in the water was found to influence the error in the expected value, and the error was found to approach infinity as the travel distance or sorption rate coefficient approaches zero. The sorption rate coefficient in the storage zone influences only higher-order moments. For sufficiently long distances, the error in the variance was found to be more pronounced when sorption kinetics in the storage zone was disregarded, than when sorption kinetics in the stream water was disregarded. Parameter values from a tracer experiment with Cr-51 revealed that the relative error in the variance could be more than 100%, if sorption kinetics in the storage zone is disregarded.
|
|
34. |
- Karlén, Camilla, et al.
(författare)
-
Runoff rates and ecotoxicity of zinc induced by atmospheric corrosion
- 2001
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 277:1-3, s. 169-180
-
Tidskriftsartikel (refereegranskat)abstract
- Initiated by regulatory restrictions on the use of zinc for various building and construction applications, together with a lack of knowledge related to the release of zinc induced by atmospheric corrosion, a major interdisciplinary research project was implemented to generate data to be used in future risk assessment. Runoff rates from a large number of commercially available zinc-based materials have been determined on panels inclined 45 degrees from the horizon, facing south, during a 1-year atmospheric exposure in an urban environment in Sweden. Possible environmental effects of runoff water immediately after leaving the surface of the various materials have been evaluated during two different sampling periods of varying season and zinc concentration, using the standard growth inhibition test with algae, Raphidocelis subcapitata (formerly Selenastnim capricornutum), Zinc-specific biosensors with the bacterial strain of Alcaligenes cutrophus. and computer modeling using the water-ligand model MINTEQA2 and the humic aquatic model WHAM, have been used to assess the bioavailability and chemical speciation of zinc in the runoff water. An excellent consistency between the different methods was observed. The results show considerably lower runoff rates of zinc (0.07-3.5 gm(-2) year(-1)) than previously being used for regulatory restrictions, and the concentration of zinc to be predominantly responsible for the observed toxicity of the runoff water towards the green algae. The majority of the released zinc quantity was found to be present as free hydrated zinc ions and, hence, bioavailable. The data do not consider changes in bioavailability and chemical speciation or dilution effects during entry into the environment. and should therefore only be used as an initial assessment of the potential environmental effect of zinc runoff from building applications. This interdisciplinary approach has the potential for studies on the environmental fate of zinc in soil or aquatic systems.
|
|
35. |
- Lindgren, Åsa
(författare)
-
Asphalt wear and pollution transport
- 1996
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 189-190, s. 281-286
-
Tidskriftsartikel (refereegranskat)abstract
- Studded tires cause extensive wear of road surfaces during winter producing small particles. Besides transporting different adsorbed pollutants these particles also discharge metal ions by their own natural content. The major part (95%) of the asphalt is composed of stone fractions. The rest consists mainly of bitumen, which contains trace quantities of metals. Laboratory studies in this study have demonstrated different adsorbing properties of metal ions, as well as differences in adsorption when comparing stone materials. Two stone materials, a gabbro and a porphyry, have been tested for their adsorption properties concerning Pb, Cu, Zn and Cd. The gabbro showed better adsorption capacity than the porphyry. Gabbro has coarser grains, it is softer, and also has a higher content of most metals compared to the porphyry. In all tests lead and copper are more adsorbed than zinc and cadmium. All metal ions are released at about the same pH ({approx}4)
|
|
36. |
- Müller, Barbara, et al.
(författare)
-
Adsorption of trace elements on pyrite surfaces in sulfidic mine tailings from Kristineberg (Sweden) : a few years after remediation
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 298:1-3, s. 1-16
-
Tidskriftsartikel (refereegranskat)abstract
- Laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) has been used to determine the elemental composition of the surface and interior layers of pyrite grains from the mine tailings from Kristineberg (northern Sweden) in order to determine concentration gradients between these two layers. The pyrite grains were collected from oxidized and unoxidized zones within the tailings. The aim of this study was to assess the role of pyrite surfaces as sites for the attenuation of solutes from the mine-tailings porewater. The normalized intensities of Cu, Zn, Ag, Sb, Ce, Pb and Bi are highest at the surface of each grain (within the surface layer drilled by the LA) and decrease towards the interior. The surface adsorption of Cu, Zn and Pb is more pronounced within the unoxidized than within the oxidized zone of the tailings. Copper exhibits a distinct concentration peak at the surface of the pyrite grains below the pre-remediation oxidation front. Silver, Sb, Bi, As and Au are preferably adsorbed within the uppermost layer of the oxidized zone in the tailings, where the pH is as high as 6.2. The conversion of intensity signals of the elements to concentration values in ppm was accomplished using an external calibration against an in-house pyrite standard.
|
|
37. |
- Rodushkin, Ilia, et al.
(författare)
-
Application of double focusing sector field ICP-MS for multielemental characterization of human hair and nails : Part I: Analytical methodology
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 250:1-3, s. 83-100
-
Tidskriftsartikel (refereegranskat)abstract
- The capabilities of double focusing sector field inductively coupled plasma mass spectrometry (ICP-SMS) for the determination of 71 elements in hair and nails were studied. A microwave-assisted digestion procedure with nitric acid and hydrogen peroxide as well as direct sampling of the nails by laser ablation (LA) have been tested. Examples of spectral interferences are given and different correction procedures are discussed. Method detection limits below ng g-1 were obtained for 39 elements investigated by using high-purity reagents and by taking special care to prevent contamination during preparation. However, these detection limits were insufficient for detection of some platinum group elements in the majority of the samples. The accuracy of the analytical procedure was estimated by analysis of the GBW07601 certified reference material as well as by participation in an interlaboratory comparison program. The reproducibility was assessed from replicate analysis (including sample preparation) and was found to be, as average values for all elements, 9-10% R.S.D. and 18-19% R.S.D. for hair and nails, respectively. Contribution from exogenous deposition was evaluated by analyzing samples before and after washing, as well as by studying spatial element distribution along hair and nails. It was found that even after sample washing, many elements are enriched in the surface of the nail.
|
|
38. |
- Rodushkin, Ilia, et al.
(författare)
-
Application of double focusing sector field ICP-MS for multielemental characterization of human hair and nails : Part II: A study of the inhabitants of northern Sweden
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 262:1-2, s. 21-36
-
Tidskriftsartikel (refereegranskat)abstract
- Double-focusing sector-field, inductively coupled plasma-mass spectrometry was used for the determination of 71 elements in scalp hair and fingernail samples from an urban population group living in the north-east of Sweden. Samples (n=114 for hair and n=96 for nails) were taken from subjects without known occupational exposure to metals. From these results, concentration ranges were calculated and compared with published intervals. Statistical analysis was used to elucidate differences according to sex, age and smoking habit. It was found that significant correlations exist between different elements in hair and nails, as well as between hair and nail concentrations for several elements. Strong positive correlation for Hg, Cd, Pb, Sb and Bi levels between these media confirms that both can be used for exposure assessment for these elements. Several examples on the use of distribution patterns for the rare-earth elements (REE) and of Pb isotope ratios for assessment of exposure are given.
|
|
39. |
- Rodushkin, Ilia, et al.
(författare)
-
Application of double focusing sector field ICP-MS for multielemental characterization of human hair and nails : Part III: Direct analysis by laser ablation
- 2003
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 305:1-3, s. 23-39
-
Tidskriftsartikel (refereegranskat)abstract
- The capabilities of laser ablation double focusing sector field inductively coupled plasma mass spectrometry for the determination of 55 elements in nails and hair were studied. Quantification was performed by external calibration using in-house matrix-matched standards in tablet form following correction for variations in ablation efficiency by internal standardization using a matrix element (S). For nails, intra-individual long- and short-term chronological variations as well as depth distribution patterns were studied. For the majority of elements tested, significant enrichment was found in the surface of the nail. Element distributions along a hair strand were investigated with a spatial resolution of 2.5 mm.
|
|
40. |
- Rodushkin, Ilia, et al.
(författare)
-
Multi-element analysis of wild berries from northern Sweden by ICP techniques
- 1999
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 231:1, s. 53-65
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, the abundances of 60 chemical elements were determined in berries of blueberry (Vaccinium myrtillus) and lingonberry (Vaccinium vitis-idaea) by a combination of inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma double focusing sector field mass spectrometry (ICP-SMS). Samples of both species were collected at 35 sites in northern Sweden. The sites are related to four zones representing areas affected by different types of human activity as well as an adjacent reference area. Special care was taken to keep sample contamination during sampling and sample preparation as low as possible. Different approaches such as use of an internal quality control sample, spike recovery tests and comparison between different analytical techniques, were used to ensure the quality of the results. Variations in element concentrations within individual sampling sites were estimated, based upon in-site duplicate sampling and analysis. The contribution from surface contamination to total berry concentrations was assessed by analysis of samples before and after rinsing with water. A comparison of the two species showed that, in spite of very similar concentrations for the majority of the elements, the highest Tl, Sr and Ba values were found in lingonberry while the highest Cl and Re concentrations were found in blueberry. The highest total concentrations of Ag, As, Be, Bi, Br, Cd, Hg, I, Ni, Pb, Sb and Tl were found in berries from mining areas, whereas those of Li, V, Hf, W, Ta and REE were found in the vicinity of high-traffic roads.
|
|
41. |
- Sjoblom, A., et al.
(författare)
-
The influence of humic substances on the speciation and bioavailability of dissolved mercury and methylmercury, measured as uptake by Chaoborus larvae and loss by volatilization
- 2000
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 261:1-3, s. 115-124
-
Tidskriftsartikel (refereegranskat)abstract
- The influence of dissolved humic substances (HS) on the bioavailability of dissolved inorganic and methyl mercury (Hg) was quantified by measuring the direct uptake of 203Hg in Chaoborus larvae using laboratory microcosms containing artificial freshwater. The animals were exposed individually in triplicate aquaria at 10 different concentrations of HS covering the whole range found in natural freshwaters (0-110 mg C l-1). Mercury-203 concentrations were monitored repeatedly in the same individuals and in their ambient water during up to 10 days. Near-steady state Hg concentrations in Chaoborus were usually reached within 5 days. The bioconcentration factor (BCF, direct uptake only) for the larvae in the absence of HS was 0.55 ± 0.09 (S.E.) ml individual-1 for inorganic Hg and 5.3 ± 0.7 ml individual-1 for methyl Hg, thus showing a 10-fold difference. Normalizing to the organic carbon content of the larvae yields a BCF(OC) in the absence of HS of 2.8 ± 0.4 x 103 ml (gC)-1 for inorganic Hg and 2.7 ± 0.3 x 104 ml (gC)-1 for methyl Hg. The uptake of both inorganic and methyl Hg decreased markedly with increasing concentration of HS. For inorganic Hg, the decrease in uptake was most pronounced at HS concentrations below 0.2 mg C l-1. For methyl Hg, the relationship between uptake and log([HS]) was sigmoid, showing a reduction by >90% when increasing HS concentrations from 1 to 50 mg C l-1. Similar patterns were observed for losses of Hg from the water phase, mainly through volatilization. These results have implications for both the biouptake and the abiotic cycling of Hg in natural ecosystems and suggest that most dissolved inorganic Hg is bound to dissolved organic matter in most natural freshwaters, whereas dissolved methyl Hg is bound only in humic waters. Assuming that only free aqueous Hg is taken up by the organisms, the rather simple methodology employed here can be used for estimating distribution coefficients (K(OC)) for Hg between HS and water. In this study, the K(OC) values were 2.5 ± 0.7 (S.E.) x 107 ml (gC)-1 for inorganic Hg and 1.5 ± 0.6 x 105 ml (gC)-1 for methyl Hg. Values of similar magnitude were derived from observed losses of Hg from the water phase, supporting the assumption of an immobilization of both inorganic and methyl Hg by HS. The strong negative influence of dissolved HS on the bioavailability of both inorganic and methyl Hg in freshwater suggests that the high Hg levels often found in fish from humic lakes in the boreal forest zone cannot be explained alone by direct uptake of methyl Hg from the water phase into biota at low trophic levels. (C) 2000 Elsevier Science B.V.
|
|
42. |
- Sörme, Louise, et al.
(författare)
-
Sources of heavy metals in urban wastewater in Stockholm
- 2002
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 298:1-3, s. 131-145
-
Tidskriftsartikel (refereegranskat)abstract
- The sources of heavy metals to a wastewater treatment plant was investigated. Sources can be actual goods, e.g. runoff from roofs, wear of tires, food, or activities, e.g. large enterprises, car washes. The sources were identified by knowing the metals content in various goods and the emissions from goods to sewage or stormwater. The sources of sewage water and stormwater were categorized to enable comparison with other research and measurements. The categories were households, drainage water, businesses, pipe sediment (all transported in sewage water), atmospheric deposition, traffic, building materials and pipe sediment (transported in stormwater). Results show that it was possible to track the sources of heavy metals for some metals such as Cu and Zn (110 and 100% found, respectively) as well as Ni and Hg (70% found). Other metals sources are still poorly understood or underestimated (Cd 60%, Pb 50%, Cr 20% known). The largest sources of Cu were tap water and roofs. For Zn the largest sources were galvanized material and car washes. In the case of Ni, the largest sources were chemicals used in the WTP and drinking water itself. And finally, for Hg the most dominant emission source was the amalgam in teeth. For Pb, Cr and Cd, where sources were more poorly understood, the largest contributors for all were car washes. Estimated results of sources from this study were compared with previously done measurements. The comparison shows that measured contribution from households is higher than that estimated (except Hg), leading to the conclusion that the sources of sewage water from households are still poorly understood or that known sources are underestimated. In the case of stormwater, the estimated contributions are rather well in agreement with measured contributions, although uncertainties are large for both estimations and measurements. Existing pipe sediments in the plumbing system, which release Hg and Pb, could be one explanation for the missing amount of these metals. Large enterprises were found to make a very small contribution, 4% or less for all metals studied. Smaller enterprises (with the exception of car washes) have been shown to make a small contribution in another city, the contribution in this case study is still unknown. © 2002 Elsevier Science B.V. All rights reserved.
|
|
43. |
- Tossavainen, Mia, et al.
(författare)
-
Potential leachability from natural road construction materials
- 1999
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 239:1-3, s. 31-47
-
Tidskriftsartikel (refereegranskat)abstract
- Leaching characteristics are used for the evaluation of waste materials in road construction. Few leaching tests have been performed on natural rock materials which implies that there is a lack of data to be used in comparison with waste materials. In order to form a basis for comparison of the leachability, nine natural road construction materials in Sweden were investigated using the availability test NT ENVIR 003. The results show that the leachable amounts of heavy metals and sulphur generally are very small, but under oxidizing conditions the solubility of sulphide bound elements increases notably. Vanadium and chromium are probably present as ionic substitutes for other elements in mineral lattices and show very low leachability. The leachable amounts of some heavy elements, e.g. zinc, nickel and copper are higher in the rock materials and gravels than in the blast furnace slags.
|
|
44. |
- van Hees, Patrick, et al.
(författare)
-
Aluminium speciation in forest soil solution- modelling the contribution of low molecular weight organic acids
- 2001
-
Ingår i: Science Of The Total Environment. - 0048-9697. ; 278:1-3, s. 215-229
-
Tidskriftsartikel (refereegranskat)abstract
- The concentrations of Al bound to identified low molecular weight organic acids (LMWOAs), phosphate and humic compounds in soil solutions (O1, O2, E, B1 and B2 horizons) from Fennoscandinavian coniferous forest soils were calculated. Two models were evaluated: WHAM (Winderemere Humic Aqueous Model) and a model treating the natural organic acids as monoprotic. The WHAM model was calibrated to find an average charge balance of unity, and then used for Al speciation. This was achieved considering approximately 80% of the natural fulvic acid to be 'active'. For the monoprotic model, constants obtained from previous fitting of soil solution data were used and the model was calibrated using acid/base titrations. The modelling confirms that the low molecular weight acids are important complex formers, binding on average 11-42% (O), 19-20% (E), and 0-30% (B) of the total Al in solution depending on the model used. The monoprotic model yielded higher concentrations than WHAM. Both models predicted that the major part of Al in solution was organically complexed to humic substances and LMWOAs, which was consistent with analytical values of 'quickly reacting' Al (monomenc inorganic forms; 12-14% of Altot on average in the E and B1 solutions). Both models could predict the magnitude of the analytical values (RMSD=4-5 μM). On average the WHAM model showed a better fit for the E horizon solutions and the monoprotic model for the upper B horizon. The pH dependence of the low molecular weight fraction of Al was modelled in the pH range 3-5.5 for a 'typical' O1 and E solution assuming no other changes in soil solution composition. The extrapolation showed that the models had a different pH dependence. The concentration of Al bound to LMWOAs in WHAM decreased with higher pH while the opposite was seen for the monoprotic model. Also the influence of the concentration of total Al in solution was modelled. The models showed similar trends but for the 'typical' O1 horizon sample the monoprotic model yielded higher concentrations of Al bound to LMWOAs than WHAM.
|
|
45. |
- Viklander, Maria
(författare)
-
Snow quality in the city of Lulea, Sweden : time-variation of lead, zinc, copper and phosphorus
- 1998
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 216:1-2, s. 103-112
-
Tidskriftsartikel (refereegranskat)abstract
- The quality of urban snow was studied with regard to how the concentrations of selected metals and phosphorus vary over time. The area studied is situated in northern Sweden (65°36 prime N; 22°13 prime E). Snow samples were taken at three different locations in the city centre, approximately every second week, throughout winter. This study has clearly shown the importance of local conditions and snow clearance operations on snow quality. The study also shows that it is difficult to interpret and predict the concentrations of lead, zinc, copper and phosphorus in the snow. However, it should be possible to predict the mass loads of these substances from the deposition velocities, if the snow handling methods and routines, as well as the local circumstances are known.
|
|
46. |
- Viklander, Maria
(författare)
-
Urban snow deposits : pathways of pollutants
- 1996
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 189-190, s. 379-384
-
Tidskriftsartikel (refereegranskat)abstract
- The pathways of pollutants in urban snow deposits have been studied in the laboratory, in a pilot study and at an actual deposit. The fractions of dissolved and particle-bound substances in the snow and melt water were studied. The results showed that almost all substances in the snow were attached to particles, while in the melt water more than 50% of most substances were dissolved. A large part of the substances which were attached to particles stayed in the sediment below the deposit, while the dissolved substances were mainly removed with the melt water.
|
|
47. |
|
|
48. |
|
|
49. |
- Adem Esmail, Blal, Dr, 1982-, et al.
(författare)
-
Boundary work for implementing adaptive management : A water sector application
- 2017
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 593-594, s. 274-285
-
Tidskriftsartikel (refereegranskat)abstract
- Boundary work, defined as effort to mediate between knowledge and action, is a promising approach for facilitating knowledge co-production for sustainable development. Here, we investigate a case study of knowledge co-production, to assess the applicability of boundary work as a conceptual framework to support implementing adaptive management in the water sector. We refer to a boundary work classification recently proposed by Clark et al., (2016), based on three types of knowledge uses, i.e. enlightenment, decision-, and negotiation-support, and three types of sources, i.e. personal expertise, single, and multiple communities of expertise. Our empirical results confirm boundary work has been crucial for the three types of knowledge use. For enlightenment and decision support, effective interaction among knowledge producers and users was achieved through diverse boundary work practices, including joint agenda setting, and sharing of data and expertise. This initial boundary work eased subsequent knowledge co-production for decision-support and negotiations, in combination with stepping up of cooperation between relevant actors, suitable legislation and pressure for problem solving. Our analysis highlighted the temporal dimension matters-building trust around enlightenment first, and then using this as a basis for managing knowledge co-production for decision-, and negotiation support. We reconfirmed that boundary work is not a single time achievement, rather is a dynamic process, and we emphasized the importance of key actors driving the process, such as water utilities. Our results provide a rich case study of how strategic boundary work can facilitate knowledge co-production for adaptive management in the water sector. The boundary work practices employed here could also be transferred to other cases. Water utilities, as intermediaries between providers and beneficiaries of the important water-related ecosystem service of clean water provision, can indeed serve as key actors for initiating such boundary work practices. (C) 2017 Elsevier B.V. All rights reserved
|
|
50. |
- Adyari, Bob, et al.
(författare)
-
Strong impact of micropollutants on prokaryotic communities at the horizontal but not vertical scales in a subtropical reservoir, China
- 2020
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 721
-
Tidskriftsartikel (refereegranskat)abstract
- Micropollutants have become of great concern, because of their disrupting effects on the structure and function of microbial communities. However, little is known about the relative importance of trace micropollutants on the aquatic prokaryotic communities as compared to the traditional physico-chemical characteristics, especially at different spatial dimensions. Here, we investigated free-living (FL) and particle-associated (PA) prokaryotic communities in a subtropical water reservoir, China, across seasons at horizontal (surface water) and vertical (depth-profile) scales by using 16S rRNA gene amplicon sequencing. Our results showed that the shared variances of physico-chemicals and micropollutants explained majority of the spatial variations in prokaryotic communities, suggesting a strong joint effect of the two abiotic categories on reservoir prokaryotic communities. Micropollutants appeared to exert strong independent influence on the core sub-communities (i.e., abundant and wide-spread taxa) than on the satellite (i.e., less abundant and narrow-range taxa) counterparts. The pure effect of micropollutants on both core and satellite sub-communities from FL and PA fractions was similar to 1.5 folds greater than that of physico-chemical factors at the horizontal scale, whereas an opposite effect was observed at the vertical scale. Moreover, eight micropollutants including anti-fungal agents, antibiotics, bisphenol analogues, stimulant and UV-filter were identified as the major disrupting compounds with strong associations with core taxa of typical freshwater prokaryotes. Altogether, we concluded that the ecological disrupting effects of micropollutants on prokaryotic communities may vary along horizontal and vertical dimensions in freshwater ecosystems.
|
|