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  • 1. Aksmann, Anna
    et al.
    Shutova, Tatiana
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Tukaj, Zbigniew
    The mechanism of anthracene interaction with photosynthetic apparatus: A study using intact cells, thylakoid membranes and PS II complexes isolated from Chlamydomonas reinhardtii2011Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 104, nr 3-4, s. 205-210Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Intact cells of Chlamydomonas reinhardtii as well as isolated thylakoid membranes and photosystem II complexes were used to examine a possible mechanism of anthracene (ANT) interaction with the photosynthetic apparatus. Since ANT concentrations above 1 mM were required to significantly inhibit the rate of oxygen evolution in PS II membrane fragments it may indicate that the toxicant did not directly interact with this photosystem. On the other hand, stimulation of oxygen uptake by ANT-treated thylakoids suggested that ANT could either act as an artificial electron acceptor in the photosynthetic electron transport chain or function as an uncoupler. Electron transfer from excited chlorophyll to ANT is impossible due to the very low reduction potential of ANT and therefore we propose that toxic concentrations of ANT increase the thylakoid membrane permeability and thereby function as an uncoupler, enhancing electron transport in vitro. Hence, its unspecific interference with photosynthetic membranes in vitro suggests that the inhibitory effect observed on intact cell photosynthesis is caused by uncoupling of phosphorylation. 

  • 2. Gyllenhammar, Irina
    et al.
    Eriksson, Hanna
    Söderqvist, Anneli
    Lindberg, Richard
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Berg, Cecilia
    Clotrimazole exposure modulates aromatase activity in gonads, brain during gonadal differentiation in Xenopus tropicalis frogs2009Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 91, nr 2, s. 102-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Clotrimazole is a pharmaceutical used for treatment of fungal infections. It has been found in surface waters outside municipal waste water treatment plants but data are scarce regarding its effects on aquatic organisms. It is known that clotrimazole and other imidazole fungicides are inhibitors of the enzyme aromatase (CYP 19). Aromatase converts androgens into estrogens and is suggested to be involved in the sex differentiation in amphibians. The aim of the present study was to evaluate effects of larval exposure to clotrimazole on aromatase activity in brain and gonads, and on gonadal differentiation in Xenopus tropicalis frogs. Another purpose was to determine if larval exposure to ethynylestradiol (EE2), at a concentration known to cause male-to-female sex reversal, affects aromatase activity in brain and gonads during gonadal differentiation. Tadpoles were exposed from shortly after hatching (Nieuwkoop and Faber developmental stage 47-48) until complete metamorphosis (NF stage 66) to 6, 41, and 375 nM clotrimazole or 100 nM (nominal) EE2. Aromatase activity was measured in the brain and gonad/kidney complex of tadpoles during gonadal differentiation (NF stage 56) and, in the clotrimazole experiment, also at metamorphosis. In clotrimazoleexposed tadpoles gonadal aromatase activity increased over exposure time in the 41- and 375 nM groups but did not differ significantly from the control group. Gonadal aromatase activity was increased in both sexes exposed to 41 and 375 nM clotrimazole at metamorphosis. Brain aromatase activity was decreased in tadpoles (NF stage 56) exposed to 375 nM clotrimazole, but at metamorphosis no differences were seen between groups or between sexes. No effects of clotrimazole on sex ratio or gonadal histology were noted at completed metamorphosis. EE2-exposed tadpoles had a slightly decreased gonadal aromatase activity, though not significantly different from control group, and there was no effect of EE2 on brain aromatase activity. All EE2-exposed tadpoles developed ovaries. These findings indicate that estrogen-induced ovarian differentiation is not paralleled by increased gonadal aromatase activity in X. tropicalis. Further studies are needed, especially on developmental reproductive toxicity, to assess the risk for endocrine disruption in wild amphibians posed by clotrimazole and other imidazole fungicides.

  • 3. Haldén, Anna Norman
    et al.
    Nyholm, Jenny Rattfelt
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Patrik L
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Holbech, Henrik
    Norrgren, Leif
    Oral exposure of adult zebrafish (Danio rerio) to 2,4,6-tribromophenol affects reproduction2010Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 100, nr 1, s. 30-7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The bromophenol 2,4,6-tribromophenol (TBP) is widely used as an industrial chemical, formed by degradation of tetrabromobisphenol-A, and it occurs naturally in marine organisms. Concentrations of TBP in fish have been related to intake via feed, but little is known about effects on fish health after oral exposure. In this study, we exposed adult male and female zebrafish (Danio rerio) to TBP via feed in nominal concentrations of 33, 330, and 3300 μg/g feed (or control feed) for 6 weeks to assess the effects of TBP on reproductive output, gonad morphology, circulatory vitellogenin levels, and early embryo development. The aim was also to investigate the extent to which TBP was metabolised to 2,4,6-tribromoanisole (TBA) in dietary exposed zebrafish, and the amounts of TBP and TBA found in offspring. After 6 weeks of exposure, we found about 3% of the daily dose of TBP in adult fish and the mean concentration of TBA was 25-30% of the TBP concentration. TBP and TBA were detected in offspring with wet weight-based egg/fish concentration ratios well below one. Exposure to TBP significantly reduced the fertilization success and disturbed the gonad morphology, i.e. fewer spermatid cysts in males and increased presence of atretic follicles and oocytes with decreased vitellogenesis in females. In females, the disturbed gonad morphology was accompanied by increased levels of circulating vitellogenin. Significant effects were observed at 3300 μg/g feed. Offspring early development was not significantly affected, but yolk-sac oedema tended to increase in frequency in exposed groups with time. Our results show that dietary exposure to TBP, at concentrations found in marine organisms that are part of the natural diet of wild fish, can interfere with reproduction in zebrafish. We also observed low accumulation from feed of TBP in zebrafish and biotransformation of TBP to TBA. This is the first paper showing gonadal histopathological changes and effects on fertility in TBP exposed fish.

  • 4.
    Hellström, Gustav
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Jonsson, Micael
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Upscaling behavioural studies to the field using acoustic telemetry2016Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 170, s. 384-389Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Laboratory-based behavioural assays are often used in ecotoxicological studies to assess the environmental risk of aquatic contaminants. While results from such laboratory-based risk assessments may be difficult to extrapolate to natural environments, technological advancements over the past decade now make it possible to perform risk assessments through detailed studies of exposed individuals in natural settings. Acoustic telemetry is a technology to monitor movement and behaviour of aquatic organism in oceans, lakes, and rivers. The technology allows for tracking of multiple individuals simultaneously with very high temporal and spatial resolution, with the option to incorporate sensors to measure various physiological and environmental parameters. Although frequently used in fisheries research, aquatic ecotoxicology has been slow to adopt acoustic telemetry as a tool in field-based studies. This mini-review intends to introduce acoustic telemetry to aquatic ecotoxicologists, focusing on the potential of the technology to bridge the gap between laboratory assays and natural behaviours when making toxicological risk assessments.

  • 5.
    Heynen, Martina
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Backstrom, Tobias
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jonsson, Micael
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Home alone: the effects of isolation on uptake of a pharmaceutical contaminant in a social fish2016Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 180, s. 71-77Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A wide range of biologically active pharmaceutical residues is present in aquatic systems worldwide. As uptake potential and the risk of effects in aquatic wildlife are directly coupled, the aim of this study was to investigate the relationships between stress by isolation, uptake and effects of the psychiatric pharmaceutical oxazepam in fish. To do this, we measured cortisol levels, behavioral stress responses, and oxazepam uptake under different stress and social conditions, in juvenile perch (Percafluviatilis) that were either exposed (1.03 mu gl(-1)) or not exposed to oxazepam. We found single exposed individuals to take up more oxazepam than individuals exposed in groups, likely as a result of stress caused by isolation. Furthermore, the bioconcentration factor (BCF) was significantly negatively correlated with fish weight in both social treatments. We found no effect of oxazepam exposure on body cortisol concentration or behavioral stress response. Most laboratory experiments, including standardized bioconcentration assays, are designed to minimize stress for the test organisms, however wild animals experience stress naturally. Hence, differences in stress levels between laboratory and natural environments can be one of the reasons why predictions from artificial laboratory experiments largely underestimate uptake of oxazepam, and other pharmaceuticals, in the wild.

  • 6. Kvarnryd, Moa
    et al.
    Grabic, Roman
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Brandt, Ingvar
    Berg, Cecilia
    Early life progestin exposure causes arrested oocyte development, oviductal agenesis and sterility in adult Xenopus tropicalis frogs2011Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 103, nr 1-2, s. 18-24Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Levonorgestrel (LNG) is a commonly used pharmaceutical progestin found in the environment. Information on the long-term toxicity of progestins following early life exposure is scant. We investigated the effects of developmental LNG exposure on sex differentiation, reproductive organ development and fertility in the model frog Xenopus tropicalis. Tadpoles were exposed to 0, 0.06 or 0.5 nM LNG via the water from hatching until metamorphosis. At metamorphosis effects on gonadal differentiation were evaluated using a subsample of frogs. Remaining animals were held unexposed for nine months, at which time reproductive organ structure, function and fertility were determined. LNG exposure severely impaired oviduct and ovary development and fertility. All adult females in the 0.5 nM group (n =10) completely lacked oviducts. They also displayed a significantly larger fraction of immature oocytes, arrested in meiotic prophase, than control females. Upon mating with unexposed males, only one of 11 LNG-exposed females laid eggs, whereas all control females did. No effects on testicular development, sperm count or male fertility were observed. At metamorphosis, no effects on sex ratio or gonadal histology were evident. The effects on ovarian and oviductal development were detected at adult age but not at metamorphosis, emphasising the importance of investigating the long-term consequences of developmental exposure. This is the first developmental reproductive toxicity study of a progestin in an aquatic vertebrate. Considering that several progestins are present in contaminated surface waters, further investigation into the sensitivity of frogs to progestins is warranted to understand the risk such compounds may pose to wild frog populations.

  • 7. Li, Zhi-Hua
    et al.
    Zlabek, Vladimir
    Grabic, Roman
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Li, Ping
    Machova, Jana
    Velisek, Josef
    Randak, Tomas
    Effects of exposure to sublethal propiconazole on the antioxidant defense system and Na+-K+-ATPase activity in brain of rainbow trout, Oncorhynchus mykiss2010Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 98, nr 3, s. 297-303Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Propiconazole (PCZ), a triazole fungicide, is widely present in the aquatic environment, but little is known regarding its chronic toxicity in the fish brain. This study assessed the effects of long-term exposure to PCZ on the antioxidant defense system and Na(+)-K(+)-ATPase activity of rainbow trout brain. Fish were exposed to sublethal concentrations of PCZ (0.2, 50, and 500 microg/l) for 7, 20, and 30 days, respectively. Oxidative stress indices (reactive oxygen species, lipid peroxidation, and carbonyl protein) and antioxidant parameters (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and reduced glutathione) were measured, as well as Na(+)-K(+)-ATPase activity. Adaptive responses to PCZ-induced stress were observed at 7 days. With prolonged exposure, significantly higher levels of oxidative indices were indicative of oxidative stress, as also were the significant inhibition of antioxidant enzyme activity and reduced glutathione content. Na(+)-K(+)-ATPase activity was significantly inhibited after prolonged exposure. Chemometrics of all parameters by principal component analysis, enabled the separation of sampled individuals into four groups with 93.39% of total accumulated variance. A low level of oxidative stress can induce the adaptive responses of the antioxidant defense system, while prolonged exposure to PCZ may lead to serious oxidative damage in fish brain. We suggest that selected biochemical markers in fish brain could be used as potential biomarkers for monitoring residual fungicides present in the aquatic environments.

  • 8.
    McCallum, Erin
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Sundelin, Anna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Alanärä, Anders
    Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hellström, Gustav
    Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Investigating tissue bioconcentration and the behavioural effects of two pharmaceutical pollutants on sea trout (Salmo trutta) in the laboratory and field2019Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 207, s. 170-178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pharmaceuticals entering aquatic ecosystems via wastewater effluents are of increasing concern for wild animals. Because some pharmaceuticals are designed to modulate human behaviour, measuring the impacts of exposure to pharmaceuticals on fish behaviour has become a valuable endpoint. While laboratory studies have shown that pharmaceuticals can affect fish behaviour, there is a lack of understanding if behaviour is similarly affected in natural environments. Here, we exposed sea trout (Salmo trutta) smolts to two concentrations of two pharmaceutical pollutants often detected in surface waters: temazepam (a benzodiazepine, anxiolytic) or irbesartan (an angiotensin II receptor blocker, anti-hypertensive). We tested the hypothesis that changes to behavioural traits (anxiety and activity) measured in laboratory trials following exposure are predictive of behaviour in the natural environment (downstream migration). Measures of anxiety and activity in the laboratory assay did not vary with temazepam treatment, but temazepam-exposed fish began migrating faster in the field. Activity in the laboratory assay did predict overall migration speed in the field. In contrast to temazepam, we found that irbesartan exposure did not affect behaviour in the laboratory, field, or the relationship between the two end-points. However, irbesartan was also not readily taken up into fish tissue (i.e. below detection levels in the muscle tissue), while temazepam bioconcentrated (bioconcentration factor 7.68) rapidly (t(1/2) < 24 h). Our findings add to a growing literature showing that benzodiazepine pollutants can modulate fish behaviour and that laboratory assays may be less sensitive at detecting the effects of pollutants compared to measuring effects in natural settings. Therefore, we underscore the importance of measuring behavioural effects in the natural environment.

  • 9. Naslund, Johanna
    et al.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Asker, Noomi
    Ekman, Elisabet
    Larsson, D. G. Joakim
    Norrgren, Leif
    Diclofenac affects kidney histology in the three-spined stickleback (Gasterosteus aculeatus) at low mu g/L concentrations2017Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 189, s. 87-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diclofenac, a commonly used non-steroidal anti-inflammatory drug, is considered for regulation under the European water framework directive. This is because effects on fish have been reported at concentrations around those regularly found in treated sewage effluents (similar to 1 mu g/L). However, a recent publication reports no effects on fish at 320 mu g/L. In this study, three-spined sticklebacks (Gasterosteus aculeatus) were exposed to 0, 4.6, 22, 82 and 271 mu g/L diclofenac in flow-through systems for 28 days using triplicate aquaria per concentration. At the highest concentration, significant mortalities were observed already after 21 days (no mortalities found up to 22 mu g/L). Histological analysis revealed a significant increase in the proportion of renal hematopoietic tissue (renal hematopoietic hyperplasia) after 28 days at the lowest concentration and at all higher concentrations, following a clear dose-response pattern. Skin ulcerations of the jaw were noted by macroscopic observations, primarily at the two highest concentrations. No histological changes were observed in the liver. There was an increase in the relative hepatic mRNA levels of c7 (complement component 7), a gene involved in the innate immune system, at 22 mu g/L and at all higher concentrations, again following a clear dose-response. The bio-concentration factor was stable across concentrations, but lower than reported for rainbow trout, suggesting lower internal exposure to the drug in the stickleback. In conclusion, this study demonstrates that diclofenac causes histological changes in the three-spined stickleback at low mu g/L concentrations, which cause concern for fish populations exposed to treated sewage effluents.

  • 10.
    Norman Haldén, Anna
    et al.
    Institutionen för biomedicin och veterinär folkhälsovetenskap, Sveriges Lantbruksuniversitet.
    Arnoldsson, Kristina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Mattsson, A.
    Institutionen för biomedicin och veterinär folkhälsovetenskap; Sveriges Lantbruksuniversitet.
    Ullerås, E.
    Institutionen för biomedicin och veterinär folkhälsovetenskap, Sveriges Lantbruksuniversitet.
    Sturve, J.
    Zoologiska institutionen, Göteborgs universitet.
    Norrgren, Leif
    Institutionen för biomedicin och veterinär folkhälsovetenskap, Sveriges Lantbruksuniversitet.
    Retention and maternal transfer of brominated dioxins in zebrafish (Danio rerio) and effects on reproduction, aryl hydrocarbon receptor-regulated genes, and ethoxyresorufin-O-deethylase (EROD) activity2011Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 102, nr 3-4, s. 150-161Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Brominated dioxins have recently been detected in Baltic Sea biota. Due to their similarities to the highly toxic chlorinated dioxins, concern has been raised about their potential biological effects. The present study investigated retention and effects of brominated dioxins in adult zebrafish, as well as maternal transfer and effects on offspring. We exposed adult zebrafish for nine weeks via feed to 2,3,7,8-tetrabromodibenzo-p-dioxin (TBDD) or to a mixture of brominated dioxins (Baltic Sea mixture), which was designed to reflect relative concentrations found in Baltic Sea biota. We studied spawning success, gonad morphology, hepatic vitellogenin gene expression, and offspring early life-stage development to investigate effects on zebrafish reproduction. Hepatic ethoxyresorufin-O-deethylase (EROD) activity and hepatic expression of a number of aryl hydrocarbon receptor (AHR)-regulated genes were studied to investigate if the brominated dioxins can activate gene transcription through the AHR pathway in zebrafish. In addition, glutathione reductase activity and expression of genes involved in adaptive responses to intracellular stress were studied to investigate potential stress effects of brominated dioxins. After nine weeks of exposure, all brominated dioxins spiked to the feed were detected in female fish and transferred to eggs. Exposure to the Baltic Sea mixture and TBDD clearly induced AHR-regulated genes and EROD activity. Exposure to TBDD reduced spawning success, altered ovarian morphology and reduced hepatic vitellogenin gene expression, which implies that TBDD has a similar effect pattern as the chlorinated analogue. Overall, our results show that dietary exposure to sublethal concentrations of brominated dioxins may impair reproductive physiology in fish and induce AHR-regulated genes. (C) 2011 Elsevier B.V. All rights reserved.

  • 11. Pohl, Johannes
    et al.
    Björlenius, Berndt
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Carlsson, Gunnar
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Larsson, D. G. Joakim
    Norrgren, Leif
    Örn, Stefan
    Effects of ozonated sewage effluent on reproduction and behavioral endpoints in zebrafish (Danio rerio)2018Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 200, s. 93-101Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pharmaceutical residues and other micro-contaminants may enter aquatic environments through effluent from sewage treatment plants (STPs) and could cause adverse effects in wild fish. One strategy to alleviate this situation is to improve wastewater treatment by ozonation. To test the effectiveness of full-scale wastewater effluent ozonation at a Swedish municipal STP, the added removal efficiency was measured for 105 pharmaceuticals. In addition, gene expression, reproductive and behavioral endpoints were analyzed in zebrafish (Danio rerio) exposed on-site over 21 days to ozonated or non-ozonated effluents as well as to tap water. Ozone treatment (7 g O-3/m(3)) removed pharmaceuticals by an average efficiency of 77% in addition to the conventional treatment, leaving 11 screened pharmaceuticals above detection limits. Differences in biological responses of the exposure treatments were recorded in gene expression, reproduction and behavior. Hepatic vitellogenin gene expression was higher in male zebrafish exposed to the ozonated effluent compared to the non-ozonated effluent and tap water treatments. The reproductive success was higher in fish exposed to ozonated effluent compared to non-ozonated effluent and to tap water. The behavioral measurements showed that fish exposed to the ozonated STP effluent were less active in swimming the first minute after placed in a novel vessel. Ozonation is a capable method for removing pharmaceuticals in effluents. However, its implementation should be thoroughly evaluated for any potential biological impact. Future research is needed for uncovering the factors which produced the in vivo responses in fish.

  • 12. Safholm, Moa
    et al.
    Jansson, Erika
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Berg, Cecilia
    Mixture effects of levonorgestrel and ethinylestradiol: Estrogenic biomarkers and hormone receptor mRNA expression during sexual programming2015Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 161, s. 146-153Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Synthetic progesterone (progestins) and estrogens are widely used pharmaceuticals. Given that their simultaneous unintentional exposure occurs in wildlife and also in human infants, data on mixture effects of combined exposures to these hormones during development is needed. Using the Xenopus (Silurana) tropicalis test system we investigated mixture effects of levonorgestrel (LNG) and ethinylestradiol (EE2) on hormone sensitive endpoints. After larval exposure to LNG (0.1 nM), or EE2 (0.1 nM) singly, or in combination with LNG (0.01, 0.1, 1.0 nM), the gonadal sex ratio was determined histologically and hepatic mRNA levels of genes encoding vitellogenin (vtg beta1) and the estrogen (esr1, esr2), progesterone (ipgr) and androgen (or) receptors were quantified using quantitative PCR. All EE2-exposed groups showed female-biased sex ratios and increased vtgbeta1 mRNA levels compared with the controls. Compared with the EE2-alone group (positive control) there were no significant alterations in vtg betal levels or in sex ratios in the co-exposure groups. Exposure to LNG-alone caused an increase in ar mRNA levels in females, but not in males, compared to the controls and the co-exposed groups, indicating that co-exposure to EE2 counteracted the LNG-induced or levels. No treatment related impacts on the mRNA expression of esr1, esr2, and ipgr in female tadpoles were found, suggesting that these endpoints are insensitive to long-term exposure to estrogen or progestin. Due to the EE2-induced female-biased sex ratios, the mRNA expression data for the low number of males in the EE2-exposed groups were not statistically analyzed. In conclusion, our results suggest that induced vtg expression is a robust biomarker for estrogenic activity in exposure scenarios involving both estrogens and progestins. Developmental exposure to LNG caused an induction of hepatic or mRNA expression that was antagonized by combined exposure to EE2 and LNG. To our knowledge this is the first study to report effects of combined exposures to EE2 and LNG during the period of sexual programming. (C) 2015 Elsevier B.V. All rights reserved.

  • 13.
    Svensson, Johan
    et al.
    Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Brandt, Ingvar
    Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden.
    Brunström, Björn
    Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden.
    Environmental concentrations of an androgenic progestin disrupts the seasonal breeding cycle in male three-spined stickleback (Gasterosteus aculeatus)2014Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 147, s. 84-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Synthetic steroid hormones from contraceptive pharmaceuticals have become global aquatic contaminants. Progestins, the synthetic analogs to progesterone, are receiving increasing attention as contaminants and have been shown to impair reproduction in fish and amphibians at low ng L-1 concentrations. Certain progestins, such as levonorgestrel have androgenic properties and seem to be several orders of magnitude more potent in terms of reproductive impairment in fish than non-androgenic progestins and progestagens. We recently reported that levonorgestrel has strong androgenic effects in female three-spined sticklebacks (Gasterosteus aculeatus), including induction of the normally male-specific glue protein spiggin and suppression of vitellogenesis. In light of this we investigated if exposure to levonorgestrel could disrupt the highly androgen-dependent seasonal reproductive cycle in male sticklebacks. Male sticklebacks that were in the final stage of a breeding period were exposed to various concentrations of levonorgestrel for six weeks in winter conditions in terms of light and temperature, after which reproductive status was evaluated from gross morphology, histology and key gene transcript levels. During the experimental period the controls had transitioned from full breeding condition into the non-breeding state, including regression of secondary sex characteristics, cessation of spiggin production in the kidney, and resumption of spermatogenesis in the testes. This is ascribed to the natural drop in plasma androgen levels after breeding. However, in the groups concurrently exposed to levonorgestrel, transition to the non-breeding condition was dose-dependently inhibited. Our results show that levonorgestrel can disrupt the seasonal breeding cycle in male sticklebacks. The fitness costs of such an effect could be detrimental to natural stickleback populations. Some effects occurred at a levonorgestrel concentration of 6.5 ng L-1, well within the range of levonorgestrel levels in surface waters and may therefore occur in progestin-contaminated waters. Furthermore, the effects by levonorgestrel in the present study were likely mediated mainly by its androgenic activity, and the low concentration at which they occurred makes levonorgestrel one of the most potent androgenic contaminants known. (C) 2013 Elsevier B.V. All rights reserved.

  • 14. Svensson, Johan
    et al.
    Mustafa, Arshi
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Schmitz, Monika
    Brunstrom, Bjorn
    Developmental exposure to progestins causes male bias and precocious puberty in zebrafish (Danio rerio)2016Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 177, s. 316-323Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Progestins are aquatic contaminants that in low concentrations can impair fish reproduction. The mechanisms are likely multiple since different progestins interact with other steroid receptors in addition to progesterone receptors. Puberty is the process when animals first acquire the capability to reproduce and it comprises maturation of sperm and eggs. In zebrafish, puberty is initiated around 45 days post fertilization (dpf) in females and around 53-55 dpf in males, and is marked by increased production of pituitary gonadotropins. We exposed juvenile zebrafish from 20 to 80 dpf to the androgenic progestin levonorgestrel at concentrations of 5.5, 79 and 834 ng L-1 and to the non-androgenic progestin progesterone at concentrations of 3.7, 77 and 1122 ng L-1, during sexual differentiation and puberty. Levonorgestrel exposure caused 100% males even at the lowest concentration tested whereas progesterone did not affect the sex ratio. Transcript levels of the gonadal genes amh, CYP11B and CYP19a1a indicated that the masculinizing effect of levonorgestrel occurred very rapidly. Transcript concentrations of gonadotropins in pituitaries were low in control fish at 44 dpf, but high at 55 dpf and onward. In fish exposed to levonorgestrel or progesterone gonadotropin transcript concentrations were high already at 44 dpf, indicating that both progestins caused precocious puberty. Gonad histology at 50 dpf confirmed a well advanced sexual maturation, but only in males. Our results show that progestins can affect sexual development in fish and that the androgenic progestin levonorgestrel induces a male phenotype at concentrations similar to those detected in aquatic environments. 

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