| 1. |
- Daneshvar, Atlasi, et al.
(författare)
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Neglected sources of pharmaceuticals in river water-footprints of a Reggae festival
- 2012
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Ingår i: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 14, s. 596-603
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Tidskriftsartikel (refereegranskat)abstract
- Wastewater treatment plants (WWTPs) are commonly considered as the main source of pharmaceuticals in surface waters. Here, however, we show that an open-air festival, attracting approximately 10 000 visitors per year at the shores of River Fyris upstream of Uppsala WWTP, can temporarily result in a higher pharmaceutical input into the river water than the WWTP. Studying the influence of Uppsala Reggae festival on the occurrence of ten commonly used acidic and basic pharmaceuticals upstream, in the effluent, and downstream of the Uppsala WWTP, we found that occasional heavy rainfalls during the festival in 2008 severely increased the mass flows of all pharmaceuticals at the WWTP upstream site. Also, strong increases in ammonium (210-fold), nitrate (21-fold), and total nitrogen (21-fold) mass flows were observed. The pharmaceutical mass flows at the upstream site were up to 3.4 times higher than those observed in the WWTP effluent. In contrast, in 2009, the festival was not accompanied with rainfalls and no major additional input of pharmaceuticals and nitrogen was observed. The findings of this study give new insights into risk assessments and are relevant for monitoring programmes.
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| 2. |
- Daneshvar, Atlasi, et al.
(författare)
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Seasonal variations in the occurrence and fate of basic and neutral pharmaceuticals in a Swedish river-lake system
- 2010
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 80:3, s. 301-309
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Tidskriftsartikel (refereegranskat)abstract
- The seasonal variations in the occurrence of carbamazepine, atenolol, metoprolol, sotalol, and acebutolol were studied at seven sites along River Fyris from December 2007 to December 2008. Samples were collected from the effluent of a waste water treatment plant (WWTP), at one upstream site, and five downstream sites of the WWTP). During one occasion in May 2008, water samples were collected at different locations and depths in the recipient lake. All analytes except of acebutolol were present in both the river and the lake at quantifiable amounts at all sampling occasions. Carbamazepine was found in similar concentrations (about 90 ng L-1) at all sampling sites and all studied depths (0.5-40 m) in the lake, indicating high environmental persistence of this compound. A clear seasonal pattern was observed for the natural attenuation of the beta-blockers in the river, with the highest attenuation occurring in summer and the lowest in winter. The loss of beta-blockers on a distance of 1320 m reached up to 75% during summer time but was insignificant during winter. The seasonal variations in the loss followed the seasonal variations in water temperature and chlorophyll a mass flow suggesting that biotransformation and adsorption are the main processes responsible for the loss of the studied pharmaceuticals in River Fyris downstream the WWTP.
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| 3. |
- Daneshvar, Atlasi, et al.
(författare)
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Winter accumulation of acidic pharmaceuticals in a Swedish river
- 2010
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Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 17:4, s. 908-916
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Tidskriftsartikel (refereegranskat)abstract
- In this study, seasonal variations in the concentration profile of four analgesics and one lipid regulator were monitored on their way from a wastewater treatment plant (WWTP) effluent, along a river, and into a lake. From December 2007 to December 2008, water samples were collected monthly (n = 12) from an upstream point, the effluent, four downstream points of the WWTP, and at the point where the river merges with the lake, and the concentrations of ibuprofen, naproxen, bezafibrate, diclofenac, and ketoprofen were determined. The analytical methodology involved solid-phase extraction of the target compounds from water samples followed by liquid chromatography coupled with tandem mass spectrometry for compound separation and detection. The studied pharmaceuticals were found in the effluent at concentrations ranging from 31 to 1,852 ng l(-1) depending on the season. In the river and lake, the concentrations were much lower (6-400 ng l(-1)) mainly due to dilution but also to a season-dependent contribution from natural transformation processes. The mean mass flow of all analgesics was highest during winter while the highest mean mass flow of the lipid regulator bezafibrate was observed in spring. The WWTP is the main source of the target compounds in the aquatic environment. The observed winter accumulation signifies the importance of natural transformation processes, which can only be estimated based on mass flow data, on the fate of pharmaceuticals in the environment.
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| 4. |
- Davies, Ronnie, 1966-
(författare)
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New approaches for synthesis and analysis of adducts to N-terminal valine in hemoglobin from isocyanates, aldehydes, methyl vinyl ketone and diepoxybutane
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human exposure to harmful compounds in the environment, from intake via food, occupational exposures or other sources, could have health implications. Exposure to reactive compounds/metabolites can be identified and quantified as hemoglobin (Hb) adducts by mass spectrometry. This thesis aimed at improved synthetic pathways for reference standards, and improved analytical methods for adducts to N-terminal valine in Hb from a range of reactive compounds; isocyanates, aldehydes, methyl vinyl ketone (MVK), and diepoxybutane (DEB).Isocyanates form urea adducts with N-terminal valine by carbamoylation, which are detachable as hydantoins by hydrolysis. A new synthetic pathway for reference standards of adducts from isocyanates and a method for their analysis by liquid chromatography/mass spectrometry (LC/MS) were developed.Aldehydes form reversible imines (Schiff bases) with N-termini in Hb. After stabilisation by reduction and detachment by isothiocyanates using modified Edman methods, these adducts could be analysed by gas chromatography/mass spectrometry (GC/MS) or LC/MS. 5-Hydroxymethylfurfural, its metabolites, and other aldehydes related to exposure via food, were studied with regard to analysis by these methods with synthesised standard references. A considerably improved analytical method for imines was developed. Many of the studied adducts are too short-lived in vivo or in vitro to be used for long-term biomonitoring. However, different approaches for the analysis were evaluated.Through synthesised reference standards, an observed unknown adduct in blood was verified as the adduct from MVK. There exist both natural and anthropogenic sources for MVK.DEB, metabolite of butadiene, forms a cyclic adduct to valine-N. A new approach using hydrazinolysis of protein and enrichment by molecularly imprinted solid-phase extraction was tested on synthesised reference DEB-adduct and gave promising results.Synthesised standards were characterized by NMR, LC/MS and GC/MS.
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| 5. |
- Eriksson, Sune, 1954-
(författare)
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Acrylamide in food products : Identification, formation and analytical methodology
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to verify the indicated occurrence of acrylamide formation in heating of food, to identify factors affecting the formation, and to identify important sources of acrylamide exposure from food. As a prerequisite for the studies, gas- and liquid-chromatographic methods with mass spectrometric detection were developed for the analysis of acrylamide in food. The developed methods showed a high correlation coefficient (0.99), high sensitivity and reproducibility. Acrylamide was demonstrated to occur in heated food products, with unexpectedly high levels in potato products (up to mg/kg level in potato crisps) and in beetroot. The identity of acrylamide was confirmed by the developed methods. With potato as a food model, different factors affecting the acrylamide formation were tested. It was shown that the addition of asparagine and fructose, as well as heating temperature and time had a large impact on the formation. Other factors affecting the acrylamide content were pH, addition of other amino acids apart from asparagine, protein and other reducing sugars. No significant effects were observed from addition of neither antioxidant nor radical initiators. It was discovered that acrylamide could be formed during heating of biological materials similar to food, also at temperatures below 100 ˚C. Furthermore, it was demonstrated that a fraction of acrylamide evaporates during heating, similar to conditions for cooking in household kitchens, and during dry matter determinations in laboratories (65-130 ˚C). This constitutes an earlier unobserved source of exposure to acrylamide.The method for extraction of food was studied with regard to yield of acrylamide. It was shown that the yield at pH ≥12 increases 3 - 4 times compared to normal water extraction for some foods products. Extraction at acidic pH or with enzymatic treatment was also tested, showing no effect on yield.In a study with mice the bioaviability of acrylamide extracted with the normal water extration and at alkaline pH was compared. It was shown that the extra acrylamide released at alkaline pH gave insignificant contributions to the in vivo dose, measured by hemoglobin adducts.
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| 6. |
- Hellström, Per M., et al.
(författare)
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Slow-release L-cysteine capsule prevents gastric mucosa exposure to carcinogenic acetaldehyde : results of a randomised single-blinded, cross-over study of Helicobacter-associated atrophic gastritis
- 2017
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 52:2, s. 230-237
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Helicobacter-induced atrophic gastritis with a hypochlorhydric milieu is a risk factor for gastric cancer. Microbes colonising acid-free stomach oxidise ethanol to acetaldehyde, a recognised group 1 carcinogen. Objective: To assess gastric production of acetaldehyde and its inert condensation product, non-toxic 2-methyl-1,3-thiazolidine-4-carboxylic acid (MTCA), after alcohol intake under treatment with slow-release L-cysteine or placebo. Methods: Seven patients with biopsy-confirmed atrophic gastritis, low serum pepsinogen and high gastrin-17 were studied in a cross-over single-blinded design. On separate days, patients randomly received 200 mg slow-release L-cysteine or placebo with intragastric instillation of 15% (0.3 g/kg) ethanol. After intake, gastric concentrations of ethanol, acetaldehyde, L-cysteine and MTCA were analysed. Results: Administration of L-cysteine increased MTCA (p < .0004) and decreased gastric acetaldehyde concentrations by 68% (p < .0001). The peak L-cysteine level was 7552 +/- 2687 mu mol/L at 40 min and peak MTCA level 196 +/- 98 mu mol/L at 80 min after intake. Gastric L-cysteine and MTCA concentrations were maintained for 3 h. The AUC for MTCA was 11-fold higher than acetaldehyde, indicating gastric first-pass metabolism of ethanol. With placebo, acetaldehyde remained elevated also at low ethanol concentrations representing 'non-alcoholic' beverages and food items. Conclusions: After gastric ethanol instillation, slow-release L-cysteine eliminates acetaldehyde to form inactive MTCA, which remains in gastric juice for up to 3 h. High acetaldehyde levels indicate a marked gastric first-pass metabolism of ethanol resulting in gastric accumulation of carcinogenic acetaldehyde. Local exposure of the gastric mucosa to acetaldehyde can be mitigated by slow-release L-cysteine capsules.
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| 7. |
- Kotova, Natalia, et al.
(författare)
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(32)P-HPLC analysis of N1-(2-carboxy-2-hydroxyethyl)deoxyadenosine : A DNA adduct of the acrylamide-derived epoxide glycidamide
- 2011
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Ingår i: Toxicology Letters. - : Elsevier BV. - 0378-4274 .- 1879-3169. ; 207:1, s. 18-24
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Tidskriftsartikel (refereegranskat)abstract
- Acrylamide (AA) is produced in many types of food products cooked or processed at high temperature. AA is metabolized to the epoxide glycidamide (GA), which can bind to deoxyguanosine and deoxyadenosine in DNA. The GA-derived N7-guanine and N3-adenine adducts are the only products which so far have been analysed in vivo. Because of previous excellent experience from analysis of adducts to N1-adenine, the aim of our study was to investigate if the N1-adenine adduct of GA could be used as a biomarker of AA exposure. A (32)P-postlabelling method was developed and tested (a) on DNA modified in vitro with GA, (b) on cells treated with GA and (c) on liver DNA from mice treated with M. The N1-adenine adduct of GA (analysed after conversion to N(6)-GA-deoxyadenosine-5'-monophosphate) was easily detected in DNA reacted with GA and in DNA from cells exposed to GA, but not in DNA from mice treated with AA. The reason for this is currently not clearly understood, but some of the possible contributing factors are discussed. The application of the method in other experimental conditions should be further pursued in order to solve this matter.
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| 8. |
- Minten, Johanna, 1968-
(författare)
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Development of Methods for the Analysis of Polar Compounds in Environmental Matrices using LC/UV and LC/MS
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent years, the awareness of environmentally hazardous compounds with polar and ionizable properties has intensified. Pharmaceuticals, the pesticide tebuconazole as well as the artificial sweetener sucralose are examples of such new, emerging, contaminants. The toxicological and ecotoxicological effects of these contaminants require investigation. This has led to an increasing need for analytical methods capable of measuring polar compounds in environmental matrices. This thesis describes the use of liquid chromatography (LC) hyphenated with ultraviolet (UV) or mass spectrometric (MS) detection for four environmental applications. Paper I describes a method for the detection and qualitative analysis of hydroxyalkyl cobalamins using LC/MS. The method was part of a project for the determination of carcinogenic compounds bound as adducts to the DNA molecule. In paper II, a LC/UV method for the analysis of the pesticide tebuconazole was developed. The method was used to evaluate a novel ecotoxicological test system. Paper III describes an LC/MS method for the determination of the artificial sweetener sucralose in sewage and recipient water. The sucralose molecule and its fragments were found difficult to detect, and a method was developed as an alternative to multiple reaction monitoring (MRM). Both quadrupoles scanned the same ion, a novel technique hypothesized to reduce matrix effects compared to selected ion recording (SIR). Paper IV describes a method for the extraction and analysis of pharmaceuticals in sediment. The study emphasizes the evaluation of suitable solvents for the extraction of basic, neutral and acidic pharmaceuticals. It was concluded that an extraction solvent containing acetone : McIlvaine buffer (pH 4) was appropriate. Electrospray LC/MS in the MRM mode was used. Additional qualitative identification of non target pharmaceuticals was performed by accurate mass measurements utilizing a quadrupole time-of-flight (Q/TOF) instrument.
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| 9. |
- Moreira Bastos, Patricia, 1978-
(författare)
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Comparison of experimentally and theoretically determined oxidation and photochemical transformation rates of some organohalogens to promote prediction of persistence
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The diversity of choices we have to make everyday influence our environment and ourselves in more ways than most of us realise. Anthropogenic substances, such as flame retardants, date back as early as 450 BC when the Egyptians used alum to reduce flammability. The increasing demand for new articles has led to an increased production of chemical substances, for which many are commercially produced without complete knowledge on properties such as persistence, bioaccumulation and toxicology (PBT). Commercial compounds may be properly tested and denominated as “safe” regarding PBT properties, but their degradation products and/or metabolites may cause environmental impact. The availability of uniform and accurate data for prediction of persistence is of key importance for the understanding of chemical fate. A method to determine the susceptibility of chemicals to undergo oxidation in water has been developed and applied on several organohalogens, including PBDEs and OH-PBDEs. The method was used to determine reaction rates and the group of OH-PBDEs were subsequently subjected to photolysis by use of UV-light. Hence, susceptibility to undergo both oxidation and photolysis for the OH-PBDEs were investigated and compared to previously reported degradation rates on PBDEs. As a final step in promoting the prediction of persistence, Quantitative structure-property relationship (QSPR) models were performed on a set of compounds which had undergone photolytic degradation under similar conditions. The QSPRs were used as a preliminary step in predicting photolysis half-lives for chemical substances and to determine which physicochemical descriptors are of greatest importance thereof. This thesis presents the possibility of performing and assessing oxidation transformations on compounds of low and high water solubility, photolysis transformations in various media and using obtained data to predict behaviour via QSPR models, to promote predictions of persistence.
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| 10. |
- Pettersson, Maria
(författare)
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Endocrine disrupting compounds in effluent waters : Chemical analysis to evaluate exposure of fish
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to investigate if endocrine disruption related to the release of estrogenic and/or androgenic substances via sewage treatment plant and pulp mill effluents is significant in Swedish waters. Chemical analysis of bile fluid in combination with measurement of biomarkers was used for the evaluation of internal exposure and effects in fish.Exposure to estrogenic substances was demonstrated by pronounced induction of the yolk protein precursor vitellogenin in fish exposed in cages downstream of a small domestic Swedish sewage treatment plant. Estrogenic substances identified in bile from the fish included the natural estrogens, the synthetic estrogen ethinylestradiol and some estrogenic phenols. The bile levels of estrogenic substances corresponded well with the plasma levels of vitellogenin. Significant concentrations of the estrogenic substances were also determined in the effluent water, and it was suggested that the level of ethinylestradiol was sufficient to explain a major part of the observed estrogenicity. Low or no induction of vitellogenin was observed in fish when exposed to final effluent from two modern Swedish sewage treatment plants, and it was concluded that a well functioning biological treatment reduces the amounts of estrogenic substances from the sewage water and that slow sand filtration contributes to further reduction. A field survey along the Baltic Sea coast revealed no signs of estrogenic or androgenic disruption in recipients of sewage treatment plants or pulp mills. This is likely due to efficient water treatment and high dilution rates in the recipients. Endocrine disruption might still be of local concern in receiving waters of less treated effluents that have low dilution rates.A sensitive method for determination of estrogenic substances in water was developed, which will make it possible to establish bioconcentration relationships between water and fish, and dose-response relationships with biomarkers in fish.
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