| 1. |
- Berglind, Rune, et al.
(författare)
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Interactions between pH, potassium, calcium, bromide, and phenol and their effects on the bioluminescence of Vibrio fischeri
- 2010
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Ingår i: Journal of Toxicology and Environmental Health. - : Informa UK Limited. - 1528-7394 .- 1087-2620. ; 73:16, s. 1102-1112
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Tidskriftsartikel (refereegranskat)abstract
- Little attention has been paid to how the light produced by the bacterium Vibrio fischeri in the Microtox assay is dependent on the concentration of essential ions such as sodium and potassium, and whether the concentrations of these ions affect the sensitivity of the test system to toxic chemicals. Five selected factors, pH, potassium (K(+)), calcium (Ca(2+)), bromide (Br(-)), and phenol (Phe), were simultaneously varied over a set of systematically planned experiments according to a D-optimal design that supported the estimation of a model with linear, quadratic, and two-factor interatcions of the studied factors. The bacterial light production represented by the gamma values in the Microtox assay for the 24 selected combinations of factors was measured at 5 and 15 min. The gamma values varied from negative to positive values greater than 1, indicating stimulation and inhibition of bacterial light production, respectively. The relationship between the gamma values and the factor settings was investigated with multiple linear regression. After 5 min of exposure, the light production was significantly affected by linear and quadratic terms for K(+), pH, and Phe and an interaction between pH and Phe. The situation was more complex after 15 min of exposure, since in addition significant interactions were found for K x Phe and Ca x pH. The tolerance of V. fischeri to Phe was enhanced by increasing the K and Ca concentrations. Data indicate that the ion composition and pH of the sample, as well as the diluents, need to be considered when the toxicity of salts, water samples, and extracts of sediments and soils are tested using commercially certified toxicity test kits.
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| 2. |
- Bos, Peter MJ, et al.
(författare)
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Human risk assessment of single exposure in chemical incidents : present situation and new and increasing chemical incident scenarios
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The release of chemicals from their containment, either accidentally or deliberately, is one of the most relevant risk scenarios in Europe. A human health risk assessment is a prerequisite for chemical incident prevention, preparedness and response. European guidance and harmonized Acute Exposure Reference Values (AERVs) are urgently needed for effective human health risk assessment in the context of chemical incidents.At present, no broad European consensus is available on guidance for risk assessment, risk management and risk communication purposes in case of chemical incidents. A review of legislation, existing or currently under revision, suggests that harmonized European guidance is not expected to be developed in the short term. An increasing number of European countries are developing their own procedures to assess the human health risk of chemical incident scenarios. The AERVs thus produced serve different purposes and are not interchangeable. Lack of international harmonization seriously obstructs a consistent response in chemical emergencies with transboundary effects within and beyond the EU, will hamper multinational companies attempting to make consistent risk assessments worldwide and will hinder consistent and transparent assessment, and management and communication of risks by different stakeholders.Emerging chemical incident risk scenarios and risk drivers have been identified. It is recommended to monitor more frequently at an early stage for new trends in chemicals, scenarios and risks from chemical incidents. A need for a specific approach to deal with single exposure to mixtures of chemicals is identified, as well as for specific guidance to adequately protect professional first responders.
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| 3. |
- Carlsson, Michael, et al.
(författare)
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Galectin-3 guides intracellular trafficking of some human serotransferrin glycoforms
- 2013
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 288:39, s. 28398-28408
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Tidskriftsartikel (refereegranskat)abstract
- Transferrin internalization via clathrin-mediated endocytosis and subsequent recycling after iron delivery has been extensively studied. Here we demonstrate a previously unrecognized parameter regulating this recycling -the binding of galectin-3 to particular glycoforms of transferrin. Two fractions of transferrin, separated by affinity chromatography based on their binding or not to galectin-3, are targeted to kinetically different endocytic pathways in HFL-1 cells expressing galectin-3 but not in SKBR3 cells lacking galectin-3; the SKBR3 cells, however can acquire the ability to target these transferrin glycoforms differently after preloading with exogenously added galectin-3. In all, this study provides the first evidence of a functional role for transferrin glycans, in intracellular trafficking after uptake. Moreover, the galectin-3 bound glycoform increased in cancer, suggesting a pathophysiological regulation. These are novel aspects of transferrin cell biology, which has previously considered only degree of iron loading, but not other forms of heterogeneity.
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| 4. |
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| 5. |
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| 6. |
- Gunnarsson, David, et al.
(författare)
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Mono-(2-ethylhexyl) phthalate stimulates basal steroidogenesis by a cAMP-independent mechanism in mouse gonadal cells of both sexes
- 2008
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Ingår i: Reproduction. - 1470-1626 .- 1476-3990. ; 135:5, s. 693-703
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Tidskriftsartikel (refereegranskat)abstract
- Phthalates are widely used as plasticizers in a number of daily-life products. In this study, we investigated the influence of mono-(2-ethylhexyl) phthalate (MEHP), the active metabolite of the frequently used plasticizer di-(2-ethylhexyl) phthalate (DEHP), on gonadal steroidogenesis in vitro. MEHP (25–100 µM) stimulated basal steroid synthesis in a concentration-dependent manner in immortalized mouse Leydig tumor cells (MLTC-1). The stimulatory effect was also detected in KK-1 granulosa tumor cells. MEHP exposure did not influence cAMP or StAR protein levels and induced a gene expression profile of key steroidogenic proteins different from the one induced by human chorionic gonadotropin (hCG). Simultaneous treatment with MEHP and a p450scc inhibitor (aminoglutethimide) indicated that MEHP exerts its main stimulatory effect prior to pregnenolone formation. MEHP (10–100 µM) up-regulated hormone-sensitive lipase and 3-hydroxy-3-methylglutaryl coenzyme A reductase, suggesting that MEHP increases the amount of cholesterol available for steroidogenesis. Our data suggest that MEHP, besides its known inhibitory effect on hCG action, can directly stimulate gonadal steroidogenesis in both sexes through a cAMP- and StAR-independent mechanism. The anti-steroidogenic effect of DEHP has been proposed to cause developmental disorders such as hypospadias and cryptorchidism, whereas a stimulation of steroid synthesis may prematurely initiate the onset of puberty and theoretically affect the hypothalamic–pituitary–gonadal axis.
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| 7. |
- Gunnarsson, David, 1975-
(författare)
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Reproductive toxicology of endocrine disruptors : effects of cadmium, phthalates and phytoestrogens on testicular steroidogenesis
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A number of investigations during the last two decades describe adverse trends in male reproductive health, which have been proposed to be caused by environmental factors with endocrine disrupting properties. In contrast to many other toxicants, endocrine disruptors often do not show linear dose-response relationships typical of those found in traditional toxicological studies. For many compounds, low-dose exposure causes effects opposite to the ones seen after high-dose exposure. In addition, the timing of exposure has been found to be critical. Hence, to correctly assess the impact of endocrine disruptors on reproductive health requires in-depth knowledge of their mechanisms of action. This thesis aimed at identifying the mechanisms underlying the effects of cadmium (Cd), phthalates and phytoestrogens on testicular steroidogenesis. For this purpose, in vitro as well as in vivo models were used. Cd was found to inhibit testosterone synthesis in vivo by down-regulating LH receptor gene expression and reducing the testicular levels of cAMP and StAR protein. In addition, Cd caused a pronounced increase in testicular prostaglandin F2ɑ (PGF2ɑ), suggesting that Cd exerts its suppressive effect on steroidogenesis also by inducing the inhibitory PKC pathway. Pre-treatment with zinc (Zn) protected completely against Cd-induced effects on testosterone and PGF2ɑ. Furthermore, we observed that Cd exposure increased glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA expression in the testis. GAPDH is a potent coactivator of androgen receptor-mediated transcription and the up-regulation found in our study is probably a compensatory response to reduced testosterone concentrations. This finding is interesting since GAPDH has been proposed to have an important role in the regulation of apoptosis as well as sperm motility. We discovered that mono-(2-ethylhexyl) phthalate (MEHP), the active metabolite of the frequently used phthalate di-(2-ethylhexyl) phthalate (DEHP), stimulates Leydig cell steroidogenesis in vitro, by a cAMP- and StAR-independent mechanism. MEHP exposure caused a similar effect in granulosa cells. Gene expression analysis revealed that MEHP is likely to stimulate steroidogenesis by increasing the amount of cholesterol available for steroid synthesis. In the last investigation, we examined the effects of low-dose phytoestrogen exposure on testosterone synthesis during puberty in male goats. Isoflavones present in clover increased plasma concentrations of testosterone and free as well as total triiodothyronine (T3). T3 has previously been shown to induce testosterone synthesis and it is possible that an elevated T3 secretion underlies the increased plasma testosterone levels. Reduced fertility and reproductive tract malformations affect both the individual and the society. Hence, a sound knowledge of reproductive toxicants is of crucial importance. The findings presented in this thesis provide new insights into the reproductive toxicology of endocrine disruptors and may be valuable for risk assessment purposes.
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| 8. |
- Gustavsson, Per, et al.
(författare)
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Galectin-3 inhibits Schwann cell proliferation in cultured sciatic nerve
- 2007
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Ingår i: NeuroReport. - 1473-558X. ; 18:7, s. 669-673
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Tidskriftsartikel (refereegranskat)abstract
- The production of galectin-3, a carbohydrate-binding mammalian lectin, is upregulated in Schwann cells after peripheral nerve injury in areas where Schwann cells proliferate. Here we tested if galectin-3 affected proliferation of Schwann cells in cultured sciatic nerve segments. Galectin-3 significantly decreased the number of bromodeoxyuridine-labelled Schwann cell nuclei. Neither lactose nor a synthetic inhibitor directed against the carbohydrate-binding region abolished the effects of galectin-3. In addition, a mutant galectin-3 unable to bind endogenous carbohydrates had similar effects as normal galectin-3. We conclude that galectin-3 reduces proliferation of Schwann cells in cultured sciatic nerve segments by a mechanism which is independent of its carbohydrate-binding moiety.
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| 9. |
- Hedlund, Maria, et al.
(författare)
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Galectin mediated tethering and arrest of neutrophils under shear flow conditions
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- According to the conventional wisdom leukocyte recruitment to an inflammatory site is initiated by selectin mediated capture and rolling along the activated endothelium. The galectins are members of another family oflectins with affinity for ß-galactosides. Expressed on endothelial cells, galectin-1 and galectin-3 have been proposed to mediate cell-cell interactions during inflammation and tumor cell metastasis, and hence act as an alternative to selectins/integrins under certain circumstances. To begin testing this hypothesis, we examined the interaction of neutrophils -with a galectin-1 or galectin-3 coated surface under shear flow conditions. Both galectins were found to trigger neutrophil arrest in a dose and carbohydrate dependent manner at coating concentrations of ≥ 200 nM, and 1 dynes/cm2 wall shear stress. While, galectin-3 mediated neutrophil arrest was immediate, galectin-1 triggered a brief period of tethering before arrest. Rapidly following arrest neutrophils spread onto the galectin-coated surface. Cell spreading was accompanied by a redistribution of actin filaments, from an initial even staining with FITC-phalloidin to a more peripheral distribution in spread cells. These data suggest that galectin-1 and galectin-3 may act as adhesion molecules capturing and arresting neutrophils at sites knovvn to be less dependent on selectins and ß2integrins. They behave in part like selectins in capturing the neutrophils, but also like the integrins in triggering firm adhesion and cell spreading.
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| 10. |
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| 11. |
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| 12. |
- Heinälä, M, et al.
(författare)
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Survey on European methodologies in the risk assessment of chemical exposures in emergency response situations
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Survey on European methodologies in the risk assessment of chemical exposures in emergency response situations. Prevention or mitigation of human health effects is often the major determinant underlying chemical incident prevention policy and emergency response decisions. The ability to perform a human health risk assessment is a prerequisite for effective chemical incident prevention, preparedness and response. To identify knowledge gaps, needs and concerns relating to health risks from chemical incidents, a web-based survey was sent to various groups of stakeholders. The release of acutely toxic substances and irritating/corrosive substances appeared to be the most important risk scenario. Almost 40% of the respondents also expected a future increase of chemical terrorism or sabotage. Developments in nanotechnology were perceived as potential future risk drivers although more information is needed on the health hazards of nanoparticles. A high number of respondents also expressed concern for the consequences of globalization, international trade and higher industry efficiency demands on health risks through chemical incidents. Acute Exposure Reference Values (AERVs) were considered important cornerstones but a need was expressed for recommendations on their use for the management of chemical emergencies. Based on this survey, it is advised to develop European consensus on an authoritative methodology to derive AERVs, to design a process for their implementation and to provide guidance and training on their practical application. Attention should be paid to the widely used acutely toxic and irritating/corrosive substances, to specific endpoints such as carcinogenicity and reproductive toxicity and new and emerging chemicals. Research should focus on developing plausible scenarios for emerging human health risks from chemical incidents to allow better prioritisation of future risk assessments.
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| 13. |
- Heinälä, Milla, et al.
(författare)
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Survey on methodologies in the risk assessment of chemical exposures in emergency response situations in Europe
- 2013
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 244, s. 545-554
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Tidskriftsartikel (refereegranskat)abstract
- A scientifically sound assessment of the risk to human health resulting from acute chemical releases is the cornerstone for chemical incident prevention, preparedness and response. Although the general methodology to identify acute toxicity of chemicals has not substantially changed in the last decades, there is ongoing debate on the current approaches for human health risk assessment in scenarios involving acute chemical releases.A survey was conducted to identify 1) the most important present and potential future chemical incident scenarios and anticipated changes in chemical incidents or their management; 2) information, tools and guidance used in different countries to assess health risks from acute chemical releases; and 3) needs for new information, tools, guidance and expertise to enable the valid and rapid health risk assessment of acute chemical exposures.According to the results, there is an obvious variability in risk assessment practices within Europe. The multiplicity of acute exposure reference values appears to result in variable practices. There is a need for training especially on the practical application of acute exposure reference values. Although acutely toxic and irritating/corrosive chemicals will remain serious risks also in future the development of plausible scenarios for potential emerging risks is also needed. This includes risks from new mixtures and chemicals (e.g. nanoparticles).
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| 14. |
- Kumpiene, Jurate, et al.
(författare)
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Impact of water saturation level on arsenic and metal mobility in the Fe-amended soil
- 2009
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 74:2, s. 206-215
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Tidskriftsartikel (refereegranskat)abstract
- The impact of water saturation level (oxidizing-reducing environment) on As and metal solubility in chromium, copper, arsenic (CCA)-contaminated soil amended with Fe-containing materials was studied. The soil was mixed with 0.1 and 1 wt% of iron grit (Fe(0)) and 1, 7 and 15 wt% of oxygen scarfing granulate (OSG, a by-product of steel processing). Solubility of As and metals was evaluated by a batch leaching test and analysis of soil pore water. Soil saturation with water greatly increased As solubility in the untreated as well as in the Fe-amended soil. This was related to the reductive dissolution of Fe oxides and increased concentration of As(III) species. Fe amendments showed As reducing capacity under both oxic and anoxic conditions. The cytotoxicity of the soil pore water correlated with the concentration of As(III). The Fe-treatments as well as water saturation of soil were less significant for the solubility of Cu, Cr and Zn than for As. The batch leaching test used for waste characterization substantially underestimated As solubility that could occur under water-saturated (anaerobic) conditions. In the case of soil landfilling, other techniques than Fe-stabilization of As containing soil should be considered.
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| 15. |
- Larsson, Per-Olof, 1948, et al.
(författare)
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Ett skandalöst frikännande
- 2011
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Ingår i: Debattartikel i Göteborgs-Posten den 25 februari 2011.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 16. |
- Leffler, Ann-Sofie, et al.
(författare)
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Somatosensory perception and function of diffuse noxious inhibitory controls (DNIC) in patients suffering from rheumatoid arthritis.
- 2002
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Ingår i: European Journal of Pain. - : Wiley. - 1090-3801 .- 1532-2149. ; 6:2, s. 161-76
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Tidskriftsartikel (refereegranskat)abstract
- The purpose was to investigate the influence of ongoing pain from an inflammatory nociceptive pain with two different disease durations on somatosensory functions and the effect of heterotopic noxious conditioning stimulation (HNCS) on 'diffuse noxious inhibitory controls' (DNIC) related mechanisms. Eleven patients with rheumatoid arthritis of a short duration (<1 year) (RA1), and 10 patients with rheumatoid arthritis of longer duration (>5 years) (RA5) as well as 21 age- and sex-matched healthy controls participated. Pressure pain sensitivity, low threshold mechanoreceptive function and thermal sensitivity, including thermal pain, were assessed over a painful and inflamed joint as well as in a pain-free area, i.e. the right thigh before HNCS (cold-pressor test) and repeated at the thigh only during and following HNCS. In RA1 and RA5 allodynia to pressure was seen over the joint (p<0.02 and p<0.001 respectively) in conjunction with hypoaesthesia to light touch (p<0.02) and hyperaesthesia to innocuous cold (p<0.05) in RA5. At the thigh, allodynia to pressure was found in RA5 (p<0.002). During HNCS, the sensitivity to pressure pain decreased in patients and controls alike (p<0.001). In conclusion, over an inflamed joint allodynia to pressure was found in both RA groups, with additional sensory abnormalities in RA5. In a non-painful area, allodynia to pressure was found in RA5, suggesting altered central processing of somatosensory functions in RA5 patients. The response to HNCS was similar in both RA groups and controls, indicating preserved function of DNIC-related mechanisms.
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| 17. |
- Leffler, Ann-Sofie, et al.
(författare)
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Somatosensory perception in a remote pain-free area and function of diffuse noxious inhibitory controls (DNIC) in patients suffering from long-term trapezius myalgia.
- 2002
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Ingår i: European Journal of Pain. - : Wiley. - 1090-3801 .- 1532-2149. ; 6:2, s. 149-59
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Tidskriftsartikel (refereegranskat)abstract
- In patients with localized musculoskeletal pain, spread of pain and tenderness outside the primarily painful area and sometimes even generalization of pain have been reported, the latter possibly indicating a dysfunction of endogenous pain modulatory systems. The purpose of the study was to use patients with long-term trapezius myalgia as a model to investigate the possible influence of a localized muscle pain on somatosensory processing in a remote pain-free area and the effect of heterotopic noxious conditioning stimulation (HNCS) on 'diffuse noxious inhibitory controls' (DNIC) related mechanisms. Altered somatosensory processing may indicate subclinical derangement of endogenous modulatory systems. Ten patients with long-term (> or = 1 year) trapezius myalgia and 10 age- and sex-matched healthy controls participated. Pressure pain sensitivity, low threshold mechanoreceptive function and thermal sensitivity, including thermal pain, were assessed at the right thigh before, during and following HNCS. Pain was induced in the forearm by the tourniquet test. At rest allodynia to pressure was found at the thigh in conjunction with hypoaesthesia to cold (p<0.03 and p<0.01 respectively), in patients compared with controls. During HNCS, the sensitivity to pressure pain and suprathreshold heat pain decreased in patients and controls alike (p<0.02 and p<0.04 respectively) and returned to baseline following HNCS. In conclusion, in a remote non-painful area allodynia to pressure and hypoaesthesia to cold were found in conjunction with preserved function of DNIC-related mechanisms. Whether altered central somatosensory processing at rest may indicate a predisposition for further spread of pain is at present unclear.
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| 18. |
- Leffler, Ann-Sofie, et al.
(författare)
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Somatosensory perception in patients suffering from long-term trapezius myalgia at the site overlying the most painful part of the muscle and in an area of pain referral.
- 2003
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Ingår i: European Journal of Pain. - 1090-3801 .- 1532-2149. ; 7:3, s. 267-76
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Tidskriftsartikel (refereegranskat)abstract
- In subgroups of patients with localised musculoskeletal pain spread of pain and signs of altered somatosensory processing at painful sites, both focal and referred areas have been reported. The purpose of the study was to examine somatosensory processing in patients with mainly unilateral long-term (> or =1 year) trapezius myalgia with ongoing pain for the last 3 months in the trapezius muscle in conjunction with ongoing or recurrent referral of pain to the ipsilateral arm. Ten patients with trapezius myalgia and 10 age- and sex-matched healthy controls participated. Pressure pain sensitivity, low threshold mechanoreceptive function and thermal sensitivity, including thermal pain, were assessed at the site overlying the most painful part of the trapezius muscle and in an area of pain referral in the ipsilateral upper arm/forearm as well as in the corresponding contralateral areas. No significant difference in sensibility was found in the most affected trapezius muscle and contralaterally compared to the corresponding areas in controls. In the area of pain referral there was a significantly increased sensitivity to pressure pain compared to the homologous contralateral area (p<0.01) as well as to the corresponding area in controls (p<0.009). Compared to controls a bilaterally decreased sensitivity to light touch was found in patients in the area of referred pain (p<0.01). No differences were found in the outcome of thermal testing. These findings suggest altered central processing of somatosensory input from the area of referred pain in patients with trapezius myalgia.
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| 19. |
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| 20. |
- Leffler, Per, 1951-
(författare)
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Cadmium induced kidney dysfunction in rodents and its relevance to biomonitoring : experimental and environmental findings
- 1996
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study deals with how workers actively introduced a new technique to their own labour process. More specifically, it is concerned with how Swedish forest workers during the 1950s gradually replaced the manual one-man crosscut saw with the motor-driven saw.The workers’ own views and actions are of central importance to the analysis of this process of technical change. Therefore fifty elderly forest workers, who had worked in forests in the county of Västerbotten in northern Sweden, were interviewed. The point of departure of the study is the fact that it was the forest workers themselves who financed and bought the chain saw.The study indicates that there were two main reasons for acquiring a chain saw. The forest workers hoped to lessen the physical work load and to improve their wages. The first workers to use the chain saw I called ”the pioneers”. They had made some, but rather little, acquaintance with the chain saw before they started to use it. They were often disappointed with the new tool. In the middle of the 1950s, the construction of the chain saws was improved and, as a result, the chain saw made its breakthrough in the second half of the 1950s. Those who bought the chain saw during this period were clearly more pleased with it than the pioneers had been.A few years into the 1960s, when almost all forest workers had bought a chain saw, unemployment slowly started to increase. Simultaneously, the piecework wage system began to change. The chain saws were by this time becoming very efficient, and the benefit could and would not go solely to the forest workers. Employers and forest owners were also to have a share and they manifested this will in the wage negotiations. The forest workers responded by increasing their work tempo, to make the salaries remain at a high level, at least for the most efficient workers. For others, the older and those who were less productive, things became harder.The increase in work intensity brought with it an increase in accidents and injuries. The workers’ satisfaction in their job deteriorated.The lesson the forest workers learned, and this guided their actions when new machines were introduced later, was that it was important to act as a collective. Equally important, however, was the insight that good working conditions and a positive wage development do not only depend on technology, but on the social order in which the technology is embedded.
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| 21. |
- Leffler, Per E, et al.
(författare)
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Tungsten
- 2015. - 4
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Ingår i: Handbook on the Toxicology of Metals. - : Academic Press. - 9780123982933 ; , s. 1297-1306
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Bokkapitel (refereegranskat)abstract
- In animal models, almost half of an ingested dose of tungsten in the form of a soluble salt and a third of a deposited inhaled aerosol of tungstic oxide were reported to be rapidly absorbed. Most of the absorbed tungsten was rapidly excreted in the urine. Part of the small amount of retained tungsten was transferred from the plasma to red blood cells and distributed mainly to the spleen, kidney, and bone. About 3 months after ingestion and 6 months after inhalation, the largest proportion of the body burden of tungsten was found in bone, although this was only a very small part of the administered dose. The metabolism of tungsten is related to that of molybdenum, which it closely resembles in chemical properties. A reliable biokinetic model for tungsten in humans is required. Little is known about the toxicity of tungsten compounds, although the median lethal dose of soluble salts is relatively high in the rat. Following occupational exposure to tungsten carbide dust by inhalation, cases of pulmonary fibrosis have been reported, but this hard metal disease, as it is often called, is more likely to be caused by cobalt, with which tungsten carbide is fused. Recent studies have shown a risk of cancer induction following exposure to heavy metal tungsten alloys, which requires further investigation. Apart from occupational sources, small quantities of tungsten are present in food and water; trace quantities, related to industrial emissions, have been found in the general atmosphere. Tungsten is also present in trace amounts in human serum and in urine and feces, with elimination approximately balancing intake of the metal in the few nonindustrially exposed subjects studied. Data on the biological effects of tungsten is sparse. Industrial, medical, and military uses of tungsten have been expanding rapidly; therefore, the potential for tungsten spreading into the environment is rapidly increasing.
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| 22. |
- Leffler, Per, et al.
(författare)
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Metodik för rapportering av ingående ämnen i ammunition som har betydelse för FM-verksamhet.
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Projektet Ammunitionsmiljö har undersökt modeller för miljörapportering av ammunition kopplat till miljökonsekvensanalys, samt generering av miljödata till en accessdatafil länkad med ammunitionskatalogen AMKAT. I föreliggande rapport presenteras genomfört arbete med utökade mallar för miljörapportering. Dessa bygger på tidigare föreslagen access-datafil, den första delleveransen till Försvarets Materielverk (FMV) 2011-10-31. Projektet levereras i 3 olika delleveranser och denna rapport utgör den tredje delleveransen
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| 23. |
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| 24. |
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| 25. |
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| 26. |
- Leffler, Per, 1951-, et al.
(författare)
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Red mud katastrofen i Ungern
- 2011
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Ingår i: Omvärldsanalys katastroftoxikologi 2010. - : Kunskapscentrum för Katastroftoxikologi (KcC)..
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 27. |
- Leffler, Per, et al.
(författare)
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Toxicity and accumulation of trinitrotoluene (TNT) and its metabolites in atlantic salmon alevins exposed to an industrially polluted water
- 2014
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Ingår i: Journal of Toxicology and Environmental Health. - : Taylor & Francis Group. - 1528-7394 .- 1087-2620. ; 77:19, s. 1183-1191
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Tidskriftsartikel (refereegranskat)abstract
- A pond in an industrial area in Sweden was selected to study adverse effects on salmon alevins from 2,4,6-trinitrotoluene (TNT)-contaminated water. Chemical screening revealed heavy contamination of TNT and its degradation products, 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT), ranging from 0.05 to 230 g/kg in the sediment (dry weight) within the water system. Pond water contained 3 mg/L TNT. A dilution series of pond water mixed with tap water revealed increased death frequency in alevins down to fivefold dilution (approximate 0.4 mg TNT/L). Uptake was concentration dependent, reaching 7, 9, and 22 μg/g tissue for TNT, 2-ADNT, and 4-ADNT at the highest test concentration. A time-dependent uptake of TNT and its degradation products was found at a water concentration of 0.08 mg TNT/L. Degradation products of TNT showed a more efficient uptake compared to native TNT, and accumulation of 4-ADNT was more pronounced during the late phase of the 40-d exposure study. Bioconcentration factors (BCF) (0.34, 52, and 134 ml/g for TNT, 2-ADNT, and 4-ADNT, respectively) demonstrated a significant uptake of the metabolite 4-ADNT in alevin tissue. Disturbed physiological conditions and delayed development in alevins were not studied, but may not be excluded even at 125-fold diluted pond water (0.016 mg TNT/L). BCF data indicated that bioaccumulation of TNT metabolites need to be considered in TNT chronic toxicity. Fish species and age differences in the accumulation of TNT metabolites need to be further studied.
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| 28. |
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| 29. |
- Lewis, Jeffrey, et al.
(författare)
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The effect of subsurface military detonations on vadose zone hydraulic conductivity, contaminant transport and aquifer recharge
- 2013
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Ingår i: Journal of Contaminant Hydrology. - : Elsevier. - 0169-7722 .- 1873-6009. ; 146, s. 8-15
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Tidskriftsartikel (refereegranskat)abstract
- Live fire military training involves the detonation of explosive warheads on training ranges. The purpose of this experiment is to evaluate the hydrogeological changes to the vadose zone caused by military training with high explosive ammunition. In particular, this study investigates artillery ammunition which penetrates underground prior to exploding, either by design or by defective fuze mechanisms. A 105 mm artillery round was detonated 2.6 m underground, and hydraulic conductivity measurements were taken before and after the explosion. A total of 114 hydraulic conductivity measurements were obtained within a radius of 3m from the detonation point, at four different depths and at three different time periods separated by 18months. This data was used to produce a three dimensional numerical model of the soil affected by the exploding artillery round. This model was then used to investigate potential changes to aquifer recharge and contaminant transport caused by the detonating round. The results indicate that an exploding artillery round can strongly affect the hydraulic conductivity in the vadose zone, increasing it locally by over an order of magnitude. These variations, however, appear to cause relatively small changes to both local groundwater recharge and contaminant transport.
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| 30. |
- Lidelöw, Sofia, et al.
(författare)
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Field trials to assess the use of iron-bearing industrial by-products for stabilisation of chromated copper arsenate-contaminated soil
- 2007
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Ingår i: Science of The Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 387:1-3, s. 68-78
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Tidskriftsartikel (refereegranskat)abstract
- Two industrial by-products with high iron contents were tested for their effectiveness in the stabilisation of arsenic and trace metals in chromated copper arsenate (CCA)-contaminated soil. Steel abrasive (SA; 97% Fe0) and oxygen scarfing granulate (OSG; 69% Fe3O4) were applied at levels of 1% and 8% (w/w) respectively to two soils with different organic matter contents. Field lysimeter measurements indicated that SA and OSG treatments decreased the arsenic concentration in pore water by 68% and 92%, respectively, for the soil with low organic matter content, and by about 30% in pore water of soil with high organic matter content. At pH ≤ 6, the amended soil with low organic content contained elevated levels of manganese and nickel in their pore water, which were sufficient to induce cytotoxic effects in L-929 mouse fibroblast cells. The industrial by-products have significant potential for soil amendment at field-scale, but caution is required because of the potential release of their chemical contaminants and their reduced capacity for sorption of arsenic in organic-rich soils.
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| 31. |
- Liljedahl, B. E., et al.
(författare)
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Some ecological effects of underwater self-explosion of ammunition in Lake Lomtjärn Sweden : The impact from mercury
- 2012
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Ingår i: International Journal of Design & Nature and Ecodynamics. - 1755-7437 .- 1755-7445. ; 7:2, s. 210-226
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Tidskriftsartikel (refereegranskat)abstract
- After the Second World War, dumping in lakes was a rational way to solve the security problem with the extensive amount of unreliable or unused ageing ammunition. Most commonly the ammunition was dumped in sealed boxes or as pieces. In some cases the ammunition was deliberately detonated when dumped. In Lake Lomtjärn, a small lake in central Sweden, extremely high levels of mercury (300 mg/kg dry weight Hg) were detected in the sediments. The mercury was expected to originate from years of dumping followed by an underwater self-explosion of ignition capsule containing mercury. The lake is unique in the sense that the mercury levels are among the highest found so far in Sweden and that no other source of pollutant is present in the area. The aim of this study was to evaluate the environmental impact from the underwater explosion. Samples of sediment, bottom water, surface water, bottom fauna, littoral fauna and fi sh (muscle and liver) were analysed for metals as well as physical parameters in order to investigate effects on biota. Acute toxicity of bottom water was determined by Daphnia magna. Results showed very high mercury content (2–338 mg/kg dry weight) in sediment down to 15 cm depth evenly distributed over the whole lake and low levels for other heavy metals (As, Cd, Cu, Pb and Zn). Water showed low levels of mercury (0.02 μg/L in bottom and surface water) as for the other heavy metals (As, Cd, Cu, Pb and Zn). Disturbance of bottom fauna was found for BQI index and O/C index. Disturbance in littoral fauna was seen around the lake (low taxa in six families, ASPT index 5.4. Danish fauna index 4 and acidity index 2). Acute toxicity (Daphnia magna ) was high. Levels of mercury in perch were high (muscle 0.6–3.59 mg/kg and liver 1.05–7.64 mg/kg). It was concluded that the underwater detonation of ammunition in Lake Lomtjärn has caused very high levels of mercury in the sediment and a high impact on the ecological chain. In risk assessments aiming to remediation decisions it is recommended early to highlight expected ecological pathways of (mercury) and relevant biomarkers in the ecosystem of concern.
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| 32. |
- Mann, Koren K., et al.
(författare)
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Tungsten
- 2022. - 5
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Ingår i: Handbook on the toxicology of metals. - : Elsevier. - 9780128229460 ; , s. 869-883
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Bokkapitel (refereegranskat)abstract
- Tungsten is a rare element with a natural abundance thought to be around 1.5 parts per million. It is remarkable for its robust physical properties, making it useful for many industrial applications. Tungsten is the heaviest metal to have a known biological role as it is essential as a cofactor for oxidoreductases in some thermophilic prokaryotes. In animal models, ingested and inhaled tungsten is rapidly absorbed and excreted in the urine. The remaining tungsten in the body is distributed mainly to the spleen, kidney, and bone, with the highest tungsten accumulation in the bone. Tungsten metabolism closely resembles molybdenum in chemical properties. Occupational inhalation exposure to tungsten carbide dust has been linked to cases of pulmonary fibrosis, a hard metal disease, although the contribution of tungsten carbide versus cobalt coexposure is unclear. Small quantities of tungsten are present in food and water and trace quantities, related to industrial emissions, are found in the general atmosphere. Tungsten is also present in human serum, urine, and feces, with elimination approximately balancing intake of the metal in the few nonindustrially exposed subjects studied. Industrial, medical, and military uses of tungsten have been expanding rapidly; therefore, the potential for tungsten spreading into the environment is rapidly increasing.
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| 33. |
- Maurice, Christian, et al.
(författare)
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Improving soil investigations at brownfield sites using a flexible work strategy and screening methods inspired by the US Environmental Protection Agency's Triad approach
- 2007
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:6, s. 502-11
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Tidskriftsartikel (refereegranskat)abstract
- Investigations of polluted brownfield sites and sample analyses are expensive, and the resulting data are often of poor quality. Efforts are needed, therefore, to improve the methods used in investigations of brownfield sites to both reduce costs and improve the quality of the results. One approach that could be useful for both of these purposes is the triad strategy, developed by the US Environmental Protection Agency, in which managing uncertainty is a central feature. In the investigations reported here, a field study was conducted to identify possible ways in which uncertainties could be managed in practice. One example considered involves optimizing the uncertainty by adjusting the sizes of samples and the efforts expended in analytical work according to the specific aims of the project. In addition, the potential utility of several toxicity assessment methods for screening sites was evaluated. As well as presenting the results of these assessments, in this contribution we discuss ways in which a flexible work strategy and screening methods inspired of the triad philosophy could be incorporated into the Swedish approach to remediate brownfield sites. A tiered approach taking advantage of field and screening methods is proposed to assess brownfield sites focusing on the response and acceptable uncertainty that are required for the task.
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| 34. |
- Maurice, Christian, et al.
(författare)
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Techniques for the stabilization and assessment of treated copper- chromium- and arsenic-contaminated soil
- 2007
-
Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:6, s. 430–6-
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Tidskriftsartikel (refereegranskat)abstract
- Remediation mainly based on excavation and burial of the contaminated soil is impractical with regard to the large numbers of sites identified as being in need of remediation. Therefore alternative methods are needed for brownfield remediation. This study was conducted to assess a chemical stabilisation procedure of CCA-contaminated soil using iron-containing blaster sand or oxygen scarfing granulate. The stabilisation technique was assessed with regard to the feasibility of mixing ameliorants at an industrial scale and the efficiency of the stabilisation under different redox conditions. The stability was investigated under natural conditions in 1-m3 lysimeters in a field experiment and the effect of redox conditions was assessed in a laboratory experiment (10 l). The treatments with high additions of ameliorant (8 and 17%) were more successful in both the laboratory and field experiments, even though there was enough iron on a stochiometric basis even at the lowest addition rates (0.1 and 1%). The particle size of the iron and the mixing influenced the stabilisation efficiency. The development of anaerobic conditions, simulated by water saturation, increases the fraction of AsIII and, consequently, arsenic mobility. The use of high concentrations of OSG under aerobic conditions increased the concentrations of Ni and Cu in the pore water. However, under anaerobic conditions, it decreased the arsenic leaching compared to the untreated soil and Ni and Cu leaching was not critical. The final destination of the treated soil should govern the amendment choice, e.g. an OSG concentration around 10% may be suitable if the soil is to be landfilled under anaerobic conditions. Alternatively, the soil mixed with 1% BS could be kept under aerobic conditions in a landfill cover or in situ at brownfield site. In addition, the treatment with BS appeared to produce better effects in the long term than with OSG.
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| 35. |
- Moparthi, Lavanya, et al.
(författare)
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Human TRPA1 is a heat sensor displaying intrinsic U-shaped thermosensitivity
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- Thermosensitive Transient Receptor Potential (TRP) channels are believed to respond to either cold or heat. In the case of TRP subtype A1 (TRPA1), there seems to be a species-dependent divergence in temperature sensation as non-mammalian TRPA1 is heat-sensitive whereas mammalian TRPA1 is sensitive to cold. It has been speculated but never experimentally proven that TRPA1 and other temperature-sensitive ion channels have the inherent capability of responding to both cold and heat. Here we show that redox modification and ligands affect human TRPA1 (hTRPA1) cold and heat sensing properties in lipid bilayer and whole-cell patch-clamp recordings as well as heat-evoked TRPA1-dependent calcitonin gene-related peptide (CGRP) release from mouse trachea. Studies of purified hTRPA1 intrinsic tryptophan fluorescence, in the absence of lipid bilayer, consolidate hTRPA1 as an intrinsic bidirectional thermosensor that is modified by the redox state and ligands. Thus, the heat sensing property of TRPA1 is conserved in mammalians, in which TRPA1 may contribute to sensing warmth and uncomfortable heat in addition to noxious cold.
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| 36. |
- Ragnvaldsson, Daniel, et al.
(författare)
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Arsenic chemical species-dependent genotoxic potential in water extracts from two CCA-contaminated soils measured by DNA-repair deficient CHO-cells
- 2009
-
Ingår i: Science of the Total Environment. - : Elsevier B.V.. - 0048-9697 .- 1879-1026. ; 407:14, s. 4253-4260
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Tidskriftsartikel (refereegranskat)abstract
- Two soils with similar contamination levels from wood preservatives containing Chromium (Cr), Copper (Cu) and Arsenic (As) (CCA), were assessed for their general toxicity and genotoxicity. A set of water-based extraction methods, including pressurized liquid extraction (PLE), and batch leaching in milli-Q water and a weak CaCl2-solution, was used to produce soil extracts containing available fractions of contaminants. In addition, to obtain indications of the contaminants' bioavailability and toxic potential the genotoxicity of the extracts was estimated by testing their ability to inhibit the growth of wildtype Chinese hamster ovary cells (CHO-cells) and three genetically modified pheno-types that are deficient in different DNA-repair mechanisms. Total extractable arsenic concentrations in the extracts were comparable between the sites. However, the genotoxic potential was clearly higher in soil R extracts. The differences in genotoxic responses were related to differences in inorganic arsenic speciation. The ratio of trivalent arsenic (AsIII) to pentavalent arsenic (AsV) was higher in all soil extracts from soil R, regardless of the leaching method used. The results of the various combinations of soil extraction techniques and assays using the CHO-cell lines reflected important differences in arsenic speciation in the two soils and possible synergistic effects in CCA-related exposure. They also indicate that speciation and combinatory effects are factors that should be taken into account when assessing risks at former wood impregnation sites contaminated by CCA-agents.
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| 37. |
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| 38. |
- Ragnvaldsson, Daniel, et al.
(författare)
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Environmental Hazard Screening of a Metal-polluted Site Using Pressurized Liquid Extraction and Two In Vitro Bioassays
- 2007
-
Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:6, s. 494-501
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Tidskriftsartikel (refereegranskat)abstract
- Rapid screening methods can improve the cost effectiveness, throughput, and quality of risk assessments of contaminated sites. In the present case study, the objective was to evaluate a combination of pressurized liquid extraction and 2 in vitro bioassays for the hazard assessment of surface soil sampled from 46 points across a pyrotechnical industrial site. Pressurized liquid extraction was used to rapidly produce soil-water extracts compatible with 2 high-capacity bioassays. Hazard assessment using combined toxicological and chemical screening revealed zones with relatively high potential risks of metal pollution. Multivariate data analysis provided indications that significant inhibition in the bioassays was correlated with levels of metals in the extracts, suggesting an elevated toxic potential from certain metals. Low pH and high concentrations of dissolved organic carbon were associated with increased cytotoxicity of extracts, indicating that these factors influence metal bioavailability. The cytotoxicity observed was more strongly correlated to metal concentrations in the extracts than in the soil, suggesting that measurements of total metal concentrations in soils do not provide good indications of the soil's potential toxicity.
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| 39. |
- Ragnvaldsson, Daniel, 1976-
(författare)
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Hazard screening of contaminated sites : bioavailable fractions and biological in vitro tools
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The environmental bioavailability of contaminants, rather than their total concentrations in the soil compartment play a decisive role for the risks associated with contaminated sites. Various soil constituents and abiotic conditions have strong influence on bioavailability, which may vary substantially between different locations. It is therefore necessary to site-specifically use tools that reflect the fractions of contaminants that are available to biota and pose the highest potential environmental risks. Bioassays provide integrated toxic responses which include effects from unknown contaminants or combinatory toxic effects from mixtures of contaminants. Thus, biological effect data greatly contribute to establish more realistic exposure and risk-scenarios at contaminated sites. The work underlying this thesis presents possible techniques for high capacity screening for site-specific hazards at contaminated areas. By combining rapid water extractions and cell-based in vitro designs measures of the toxic potential in soils was obtained. Toxicologically bioavailable fractions of mixed metal pollution, including arsenic, were primarily investigated in this thesis. In two of the studies, environmental availability and toxicological bioavailability of arsenic was explored in CCA-contaminated soils. Application of cell-based in vitro screening techniques was also conducted at a metal contaminated industrial site to obtain spatial distribution of toxicity. Multivariate association techniques were employed in the interpretation of environmental exposure and cytotoxicity data. It was shown that cell-based in vitro systems for both basal cytotoxicity and specific end-points targeting arsenic could assess the toxic potential from extracts obtained by several water-based extraction techniques including Pressurised Liquid Extraction (PLE). The cell-based in vitro systems were found to add important information on the site-specific differences in arsenics genotoxic potential from CCA-contaminated soils. The results highlight the importance of taking speciation and toxicological bioavailability into account in the risk analysis, rather than to base risk estimates on total load of contaminants. The presented screening approach was successfully applied at a metal polluted industrial site where spatial distribution of toxicity was obtained. PLE extraction also provided means for combined toxicological and chemical screening of explosives in soils from live-fire training ranges. Multivariate association techniques highly facilitated the interpretation of complex environmental data. The PLE was found to be a rapid extraction technique that has sufficient environmental relevance to be used in environmental impact analyses. It was also concluded that other cell-based in vitro systems that target specific toxic effects have large potential for being used in screening for a variety of environmental chemicals. Keywords: Environmental availability, Environmental bioavailability, Toxicological bioavailability, mixture toxicity, hazard screening, contaminated soils, heavy metals, arsenic, CCA, explosives, soil extraction, water extracts, cell-based in vitro tests, cytotoxicity, genotoxicity, PLE, MVDA, PCA, PLS.
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| 40. |
- Rudjord-Levann, Asha M., et al.
(författare)
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Galectin-1 induces a tumor-associated macrophage phenotype and upregulates indoleamine 2,3-dioxygenase-1
- 2023
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Ingår i: iScience. - 2589-0042. ; 26:7
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Tidskriftsartikel (refereegranskat)abstract
- Galectins are a group of carbohydrate-binding proteins with a presumed immunomodulatory role and an elusive function on antigen-presenting cells. Here we analyzed the expression of galectin-1 and found upregulation of galectin-1 in the extracellular matrix across multiple tumors. Performing an in-depth and dynamic proteomic and phosphoproteomic analysis of human macrophages stimulated with galectin-1, we show that galectin-1 induces a tumor-associated macrophage phenotype with increased expression of key immune checkpoint protein programmed cell death 1 ligand 1 (PD-L1/CD274) and immunomodulator indoleamine 2,3-dioxygenase-1 (IDO1). Galectin-1 induced IDO1 and its active metabolite kynurenine in a dose-dependent manner through JAK/STAT signaling. In a 3D organotypic tissue model system equipped with genetically engineered tumorigenic epithelial cells, we analyzed the cellular source of galectin-1 in the extracellular matrix and found that galectin-1 is derived from epithelial and stromal cells. Our results highlight the potential of targeting galectin-1 in immunotherapeutic treatment of human cancers.
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| 41. |
- Scott Andersson, Åsa, 1970-
(författare)
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Development of an Environment-Accident Index : A planning tool to protect the environment in case of a chemical spill
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The increasing mass and complexity of chemicals being produced and transported has resulted in more rigorous demands on both authorities as well as chemical-handling industries to assess the risks involved. The Environment-Accident Index (EAI), has been proposed as a planning tool created as an equation in which chemical properties (variables describing the chemical involved) are combined with site-specific properties (variables describing the accident site). The EAI is intended to facilitate assessment of the environmental effects related to chemical accident scenarios and hence assist the organisation of preventative programs. The main objective of the work described in this thesis was to evaluate, develop and improve the proposed EAI. The steps involved in the development process included I) evaluation of the feasibility of the EAI approach, II) selection of a representative and diverse set of chemical accidents to be used in the development III) the use of questionnaires and expert judgements to develop response values for environmental effects of a chemical accident, and IV) to create a new EAI model using multivariate modelling (PLS). The EAI approach proved to be useful in the work to protect the environment in case of a chemical accident. A representative set of accidents was selected by means of statistical multivariate design (PCA) based on assembled data related to a set of 55 chemical accidents. The selection generated a set of accidents representing a diverse spectrum of chemical accident scenarios. To develop a measure of environmental effects of the chemical accidents i.e. responses, an expert panel was asked to judge their environmental effects (such as effects on animal life in the aquatic or terrestrial environment). The results showed that the judgements give a rough estimate of environmental effects that could be used as responses in the development of the EAI. The developed responses were then related to the chemical and site-specific properties to create a new EAI model. This resulted in a PLS-based EAI connected to a new classification scale. The advantages of the new EAI are that it can be calculated without the use of tables; it can estimate the effects for all included responses, and make a rough classification of chemical accidents according to the new classification scale. Finally, the new EAI is a more stable model than the previously proposed EAI, and it is founded on a valid base of accident scenarios, making its use for a variety of chemicals and situations more reliable since it covers a broader spectrum of accident scenarios. The new EAI can be expressed as a regression model to facilitate calculation of the index for people that do not have access to PLS. The highest priorities for further refining the new EAI in the future are: external validation of the EAI; further refinement of the formula’s structure; adjustment of the new classification scale; and real-life evaluation of the EAI.
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| 42. |
- Sörme, Pernilla, et al.
(författare)
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Low micromolar inhibitors of galectin-3 based on 3'-derivatization of N-acetyllactosamine.
- 2002
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Ingår i: ChemBioChem. - 1439-4227. ; 3:2-3, s. 183-189
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Tidskriftsartikel (refereegranskat)abstract
- A strategy for generating potential galectin inhibitors was devised based on derivatization at the C-3′ atom in 3′-amino-N-acetyllactosamine by using structural knowledge of the galectin carbohydrate recognition site. A collection of 12 compounds was prepared by N-acylations or N-sulfonylations. Hydrophobic tagging of the O-3 atom in the N-acetylglucosamine residue with a stearic ester allowed rapid and simple product purification. The compounds were screened in a galectin-3 binding assay and three compounds with significantly higher inhibitory activities compared to the parent N-acetyllactosaminide were found. These three best inhibitors all carried an aromatic amide at the C-3′ position of the galactose moiety, which indicates that favorable interactions were formed between the aromatic group and galectin-3. The best inhibitor had an IC50 value (4.4 μM) about 50 times better than the parent N-acetyllactosaminide, which implies that it has potential as a valuable tool for studying galectin-3 biological functions and also as a lead compound for the development of galectin-3-blocking pharmaceuticals.
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