| 1. |
- Hellström, Anders, et al.
(författare)
-
8. Aquaculture and Fish Health
- 2012. - 1
-
Ingår i: Ecology and Animal Health. - Uppsala : Baltic University Press. - 9789186189129 ; , s. 63-72
-
Bokkapitel (populärvet., debatt m.m.)
|
|
| 2. |
- Arnoldsson, Kristina, 1961-, et al.
(författare)
-
Retention and maternal transfer of environmentally relevant polybrominated dibenzo-p-dioxins and dibenzofurans, polychlorinated dibenzo-p-dioxins and dibenzofurans, and polychlorinated biphenyls in zebrafish (Danio rerio) after dietary exposure
- 2012
-
Ingår i: Environmental Toxicology and Chemistry. - : John Wiley & Sons. - 0730-7268 .- 1552-8618. ; 31:4, s. 804-812
-
Tidskriftsartikel (refereegranskat)abstract
- High levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), mono- and non-ortho polychlorinated biphenyls (PCBs), and polybrominated dibenzo-p-dioxins (PBDDs) are found in fish from coastal areas in the Baltic Sea, which may cause ecotoxicological effects. To increase our understanding of the persistency of the emerging pollutants polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), fish feed was spiked with 21 PBDD/Fs, 17 PCDD/Fs, and 30 PCBs and fed to zebrafish. Concentrations in fish and eggs were examined during a six- or twelve-week uptake period, and a six-week elimination period. Steady-state was reached for 2, 3, 7, and/or 8-substituted tri- and tetra-BDD/Fs, with 2,3,7,8-tetra-BDD (2,3,7,8-TeBDD) being the most strongly retained. Steady-state was not reached for tetra- to hexa-CDDs. Non-2,3,7,8-congeners showed little of or no retention. Most PCBs had high retention and did not reach steady-state. Half-lives decreased in the order: PCBs > PCDD/Fs > PBDD/Fs. Concentrations of 2,3,7,8-penta- to octa-CDD/Fs decreased with their degree of chlorination suggesting that the rate-limiting factor for uptake is low bioavailability. Maternal transfer was observed for all retained compounds, with most transfer factors < 1, indicating that transfer rates are affected by the poor water solubility of the compounds. The limited retention of the major PBDD congeners found in Baltic Sea fish suggests that they are exposed to high or very high concentrations via either food or water.
|
|
| 3. |
- Carlsson, Gunnar, et al.
(författare)
-
Toxicity of 15 veterinary Pharmaceuticals in zebrafish (Danio rerio) embryos
- 2013
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 126, s. 30-41
-
Tidskriftsartikel (refereegranskat)abstract
- Extensive use of veterinary pharmaceuticals may result in contamination of water bodies adjacent to pasture land or areas where animal manure has been applied. In order to evaluate the potential risk to fish embryos 15 veterinary pharmaceuticals were investigated by use of an extended zebrafish embryo toxicity test. Chemical analysis of the exposure medium was performed by solid phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) for 11 of the compounds and potential metabolism by the embryos was studied for albendazole, febantel, fenbendazole and oxfendazole. Newly fertilized zebrafish eggs were exposed under static conditions in 96-well plates for 6 days to the pharmaceuticals: 5 antibacterials and 10 antiparasitics. Endpoints including mortality, malformations and other sublethal responses were recorded at 24, 48 and 144 h post fertilization (hpf). The pharmaceuticals causing the highest toxicity were antiparasitics whereas the tested antibacterials, danofloxacin, enrofloxacin, tylosine, trimethoprim and oxytetracyclin had a much lower toxic potency in zebrafish embryos. Most toxic were fenbendazole, albendazole and flumethrin with no observed effect concentrations (NOECs) around 0.02 mg/L. The overall NOEC was determined by lethality for the following pharmaceuticals: albendazole, fenbendazole and oxfendazole. Sublethal endpoints, including malformations, side-laying embryos, tremors, reduced movements and altered heart rate increased the sensitivity of the tests and determined the overall NOECs for febantel, doramectin, ivermectin, flumethrin and toltrazuril. Exposure to doramectin and ivermectin caused a decrease in movements at 24 hpf and a decrease in heart rate at 48 hpf. Flumethrin exposure resulted in decreased time to hatching, except at the highest concentrations, and caused an increase in heart rate at 48 hpf. In contrast, toltrazuril caused an increased time to hatching and a decrease in heart rate. Chemical analysis of the exposure medium after the tests revealed great differences between nominal and measured concentrations, emphasizing the need of including analysis of the actual exposure concentrations. The results indicated that metabolism of albendazole into its sulfoxide protected the embryos from toxicity. Albendazole was metabolized efficiently into albendazole sulfoxide at lower exposure concentrations, resulting in reduced toxicity. At higher concentrations, an increasing proportion of albendazole remained unmetabolized and embryo mortality occurred. Metabolism by the embryos of febantel into fenbendazole and oxfendazole and of fenbendazole into oxfendazole was demonstrated. It is suggested that the toxic effect of febantel in zebrafish embryos is due to metabolism into fenbendazole.
|
|
| 4. |
|
|
| 5. |
- Näslund, Johanna, et al.
(författare)
-
Diclofenac affects kidney histology in the three-spined stickleback (Gasterosteus aculeatus) at low mu g/L concentrations
- 2017
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 189, s. 87-96
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
| 6. |
- Pohl, Johannes, et al.
(författare)
-
Effects of ozonated sewage effluent on reproduction and behavioral endpoints in zebrafish (Danio rerio)
- 2018
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 200, s. 93-101
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
| 7. |
|
|
