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- Carney Almroth, Bethanie, 1974, et al.
(författare)
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Assessing the effects of textile leachates in fish using multiple testing methods: From gene expression to behavior
- 2021
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Ingår i: Ecotoxicology and Environmental Safety. - : Elsevier BV. - 0147-6513 .- 1090-2414. ; 207
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Tidskriftsartikel (refereegranskat)abstract
- The textile industry, while of major importance in the world economy, is a toxic industry utilizing and emitting thousands of chemical substances into the aquatic environment. The aim of this project was to study the potentially harmful effects associated with the leaching of chemical residues from three different types of textiles: sportswear, children’s bath towels, and denim using different fish models (cell lines, fish larvae and juvenile fish). A combination of in vitro and in vivo test systems was used. Numerous biomarkers, ranging from gene expression, cytotoxicity and biochemical analysis to behavior, were measured to detect effects of leached chemicals. Principle findings indicate that leachates from all three types of textiles induced cytotoxicity on fish cell lines (RTgill-W1). Leachates from sportswear and towels induced mortality in zebrafish embryos, and chemical residues from sportswear reduced locomotion responses in developing larval fish. Sportswear leachate increased Cyp1a mRNA expression and EROD activity in liver of exposed brown trout. Leachates from towels induced EROD activity and VTG in rainbow trout, and these effects were mitigated by the temperature of the extraction process. All indicators of toxicity tested showed that exposure to textile leachate can cause adverse reactions in fish. These findings suggested that chemical leaching from textiles from domestic households could pose an ecotoxicological threat to the health of the aquatic environment.
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| 3. |
- Book, Frida, 1989, et al.
(författare)
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Aquatic ecotoxicity of manufactured silica nanoparticles: A systematic review and meta-analysis
- 2022
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 806:4
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Forskningsöversikt (refereegranskat)abstract
- Manufactured silica nanoparticles are used worldwide in large volumes for a variety of applications. An exposure of environmental organisms is therefore likely, and several data on the ecotoxicology of silica nanoparticles to different organisms have been published in recent years. This systematic review compiles and assesses these studies, in order to analyse the sensitivity distribution across different organisms. On this basis, maximum acceptable environmental concentrations are suggested and potential environmental risks are discussed. 1429 papers were retrieved from the scientific literature (Scopus), the U.S. ECOTOX knowledge database. 63 studies were finally included in the review and appraised according to the nanoCRED criteria. A total of 219 ecotoxicological endpoints recorded in 38 species (7 taxonomic groups) were condensed into a species sensitivity distribution. The resulting concentration that is hazardous for a maximum of 5% of exposed species (HC05) is 130 μg/L, from which a PNEC of 30 μg/L is estimated by applying an assessment factor of 5. These concentrations are 1-3 orders of magnitudes above the concentrations modelled to occur in European aquatic ecosystems. Algae and bacteria have a comparatively low sensitivity to MSNP exposure, likely because their cell wall forms a protective barrier against nanoparticle exposure. Similarly, embryonic stages of fish also show a comparatively low sensitivity due to the protection from their chorion. However, the fish species Labeo rohita and Oncorhynchus mykiss are among the most sensitive species. The ecotoxicity of silica nanoparticles is linked to the number of hydroxyl groups on their surface, corresponding to findings from human toxicological studies. It is recommended that future ecotoxicological studies use explicit concentration-response designs, use proven biocide-free testing material, comparatively apply mass and surface area as exposure metrics, and provide important metainformation in the study report.
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| 5. |
- Book, Frida, 1989, et al.
(författare)
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Ecotoxicity screening of seven different types of commercial silica nanoparticles using cellular and organismic assays : Importance of surface and size
- 2019
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Ingår i: NanoImpact. - : Elsevier BV. - 2452-0748. ; 13, s. 100-111
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Tidskriftsartikel (refereegranskat)abstract
- We show that seven different types of commercial, biocide-free, colloidal silica products with mean particle sizes between 17 and 88 nm with 3 different surface chemistries (Na-stabilized, aluminized and silane-modified) are not toxic to the bacterium Pseudomonas putida, and the algae Raphidocelis subcapitata in the concentration range 5–500 mg/L. They are also not acutely toxic to Daphnia magna at concentrations up to 10,000 mg/L. Six silica particles are toxic to the gill cell line RTgill-W1 from Rainbow trout (Oncorhynchus mykiss), showing a clear concentration-response relationship with EC50 values between 13 and 92 mg/L. Toxicity in the fish cells decreases with increasing hydrodynamic size and is dependent on particle surface area. The average EC50 across the tested particles is 2.1 (±0.3) m2/L. Surface modifications clearly impact toxicity, with silane-modified particles showing no cytotoxicity. The reduced number of free silanol groups on the surface of the silane modified particle, in combination with an increased steric hindrance that prevents contact with the cells is a possible mechanism for the observed lack of toxicity. This is also in line with previous studies on silica nanoparticles in human toxicology. Overall, these findings show a generally low ecotoxicity of silica nanoparticles and indicate that silica particles of different sizes but identical surface chemistry could potentially be grouped into an assessment group under regulation such as REACH.
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| 6. |
- Book, Frida, 1989
(författare)
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The aquatic ecotoxicity of manufactured silica nanomaterials and their interactions with organic pollutants
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Manufactured silica nanomaterials are one of the nanomaterials consumed in the highest volumes (more than 4 000 000 tons/year/globally) and are used in a wide range of products and industries such as food, cosmetics, coatings, paints, textiles, concrete and the paper and pulp industry. They also provide promising properties that help solving societal challenges, such as water remediation, by binding contaminants. However, their large and wide use leads to an inevitable release into surface waters, which raises concerns of potential environmental impacts, because of their small size, reactive surfaces and the risk of facilitating biological uptake of other co-occurring chemicals (“trojan horse effect”). Therefore, this thesis systematically investigates the aquatic ecotoxicity of manufactured silica nanomaterials alone and in combination with toxic organic chemicals. The thesis is based on an in-depth ecotoxicological evaluation of nine silica nanomaterials with different size, charge, surface modification and shape in experiments with bacteria (Pseudomonas putida), algae (Raphidocelis subcapitata), crustacean (Daphnia magna) and fish gill cells (Oncorhynchus mykiss). These data are then complemented with data from other scientific publications in a systematic review in the ecotoxicology of silica nanomaterials, in order to derive the maximum acceptable environment concentration in the aquatic environment (PNEC, the predicted no effect concentration). Finally, this thesis examinesthe ability of silica materials to adsorb organic pollutants with different charges: paraquat (cationic), hexadecylpyridinium (cationic), pentachlorophenol (anionic), diflufenican (neutral) and whether this interaction alters the ecotoxicity of exposed organisms and cells. The results show that impacts are a result of surface area, surface chemistry and exposed organism/cell type. Silica nanomaterial that is sterically stabilized with glycerol propyl tails is benign in all assays showing no signs of toxic action. This is likely due to a steric hindrance that prevents contact between the material and the cells/species. Weakly anionic (non-modified) and strongly anionic (aluminium-modified) silica are toxic to fish gill cells with EC50 values between 12 and 93 mg/L. This toxicity in fish cells depends on the total surface area of the nanomaterial that is covered with deprotonated silanol groups which binds to and interrupts membrane proteins function. As a consequence, if concentrations are expressed as surface area instead of mass, the toxicity of different nanomaterials becomes quite similar, with EC50 values differing not more than by a mere factor of 1.4 (1.8-2.5 m2 /L). In contrast to experiments with fish cells, strongly anionic silica is not toxic to algae at concentrations up to 500 mg/L, likely due to the presence of a cell wall, which hampers nanomaterial-cell interactions. However, cationic and non-modified silica nanomaterials cause an inhibition of algal growth, EC50 values of 124 mg/L and 200 mg/L, respectively. This effect is likely caused by an adsorption of the material to the algae, shading them and thereby impacting the photosynthetic production of physiological energy. The results from the exposures to mixtures of silica nanomaterial and organic pollutants show that strongly anionic nanomaterials bind cationic paraquat and thereby reduce paraquat toxicity to algal cells. In addition, the cationic material can bind and reduce toxicity of pentachlorophenol in algae, which is likely pH and phosphate dependant. Experiments with fish cells indicate that the anionic NMs bind the cationic hexadecylpyridinium, but do not reduce the toxicity in exposed fish cells. Instead, the observed effects correspond well with the effects predicted with the two concepts independent action and concentration addition. In general, the mixture experiments indicate that silica nanomaterials possess promising properties to bind and remove certain pollutants in water. However, the use of silica nanomaterials for such purpose in industrial applications requires additional research on the water types that can be cleaned (industrial wastewater, household wastewater, raw drinking water, surface waters etc.), life-cycle based assessments of costs and benefits, and a comparison with other materials for water treatment.
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