| 1. |
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| 2. |
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| 3. |
- Backhaus, Thomas, 1967, et al.
(författare)
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Optimisation of biocides in marine paints
- 2012
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Ingår i: Final conference of Marine Paint 14-15th of May 2012, Göteborg.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 4. |
- Wendt, Ida, 1981, et al.
(författare)
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Effects of Five Antifouling Biocides on Settlement and Growth of Zoospores from the Marine Macroalga Ulva lactuca L
- 2013
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Ingår i: Bulletin of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0007-4861 .- 1432-0800. ; 91:4, s. 426-432
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Tidskriftsartikel (refereegranskat)abstract
- Antifouling biocides are found in the marine ecosystem were they can affect non-target organisms. In this study the effects of five antifouling biocides on the settlement and growth of Ulva lactuca zoospores were investigated. The biocides investigated were copper (Cu2+), 4,5-dichloro-2-n-octyl-3(2H)-isothiazolone (DCOIT), triphenylborane pyridine (TPBP), tolylfluanid and medetomidine. Full concentration-response curves where determined for each compound. EC50 values were determined for copper, DCOIT, TPBP and tolylfluanid, all of which inhibited settlement and growth in a concentration dependent manner with the following toxicity ranking; tolylfluanid (EC50 80 nmol L-1) similar to DCOIT (EC50 83 nmol L-1) > TPBP (EC50 400 nmol L-1) > Cu2+ (EC50 2,000 nmol L-1). Medetomidine inhibited settlement and growth only at the extreme concentration of 100,000 nmol L-1 (93 % effect). The low toxicity is possibly a consequence of a lack of receptors that medetomidine can bind to in the U. lactuca zoospores.
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| 5. |
- Wendt, Ida, 1981, et al.
(författare)
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Extreme irgarol tolerance in an Ulva lactuca L. population on the Swedish west coast
- 2013
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X. ; 76:1-2, s. 360-364
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Tidskriftsartikel (refereegranskat)abstract
- The herbicide irgarol 1051 is commonly used on ship hulls to prevent growth of algae, but as a component of self-eroding paints it can also spread in the surrounding waters and affect non-target organisms. The effect of irgarol on settlement and growth of zoospores from the marine macro algae Ulva lactuca from the Gullmar fjord on the Swedish west coast was investigated in the present study. The zoospores were allowed to settle and grow in the presence of irgarol, but neither settlement - nor growth inhibition was observed at concentrations of up to 2000 nmol l(-1). This is between 10 and 100 times higher than effect concentrations reported earlier for algae. Irgarol also induced the greening effect (4-fold increase in chlorophyll a content) in the settled zoospore/germling population, typical for photosystem II inhibitors like irgarol. This study support previous findings that irgarol constitutes a selection pressure in the marine environment. (C) 2013 Elsevier Ltd. All rights reserved.
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| 6. |
- Wendt, Ida, 1981, et al.
(författare)
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The efficacy of antifouling biocides: a systematic approach
- 2010
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Ingår i: the 15th international congress on marine corrosion and fouling, 25-29 July 2010, Newcastle.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In the Marine Paint Optimization project a broad range of settling tests are used to assess the efficacy of antifoulants, in order to provide a basis for the subsequent development of optimized antifoulant mixtures. Since the fouling community is very complex, and composed of a large number of different species with vastly different sensitivities to the different antifoulants, the test approach has been to select key organisms from all the main fouling groups. By doing so the whole sensitivity range of the fouling community is captured. The “test battery” includes invertebrate larvae (barnacles (Amphibalanus improvisus), sea squirt (Ciona intestinalis) and bryozoans (Bugula neritina)) macro algae (sea lettuce (Ulva lactuca)) and biofilms (periphyton community, also referred to as slime). The sensitivity range for each individual species has been tested for a list of antifouling compounds, either in use today or likely to be registered and approved by the European Biocidal Product Directive, including Medetomedine, Copper Pyrithione, Zinc Pyrithione, Tolylfluanid, Sea-Nine (DCOIT), Copper, Borocide (TPBP) and Irgarol. EC99 for all tested species and biocides will be presented. This study is a part of the Marine Paint research programme funded by MISTRA.
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| 7. |
- Altenburger, R., et al.
(författare)
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Ecotoxicological combined effects from chemical mixtures Part 1: Relevance and adequate consideration in environmental risk assessment of plant protection products and biocides
- 2014
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- The Project deals with the possibilities of performing mixture toxicity assessment within the environmental risk assessment of the authorization of biocide and plant protection products. To this end a review on the state of scientific knowledge about the predictivity of combined effects is collated. Central in this context is the reference model of Concentration Addition which allows extrapolating combined effects for mixtures based on knowledge about the effects of the components. Building on this, options for risk regulation are developed. Their applicability is considered in the context of those data that are currently available within the authorization process for biocide and plant protection products. Deficits with respect to a – scientifically sensible – homogeneous data base can often be overcome with pragmatic decisions if additional requirements for the authorization process are not an option. Tiered schemes to specifically account for combined effects during environmental risk assessment of biocide and plant protection product authorization are suggested, accompanied with a software tool for its implementation.
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| 8. |
- Arrhenius, Åsa, 1973, et al.
(författare)
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A novel bioassay for evaluating the efficacy of biocides to inhibit settling and early establishment of marine biofilms
- 2014
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X. ; 87:1-2, s. 292-299
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a novel assay that allows a quick and robust assessment of the effects of biocides on the initial settling and establishment of marine photoautotrophic biofilms including the multitude of indigenous fouling organisms. Briefly, biofilms are established in the field, sampled, comminuted and re-settled on clean surfaces, after 72 h chlorophyll a is measured as an integrating endpoint to reflect both settling and growth. Eight antifoulants were used to evaluate the assay. Efficacy ranking, based on EC98 values from most to least efficacious compound is: copper pyrithione > TPBP > DCOIT > tolylfluanid > zinc pyrithione > medetomidine > copper (Cu2+), while ecotoxicological ranking (based on EC10 values) is irgarol, copper pyrithione > zinc pyrithione > TPBP > tolylfluanid > DCOIT > copper (Cu2+)>medetomidine. The algaecide irgarol did not cause full inhibition. Instead the inhibition leveled out at 95% effect at 30 nmol l−1, a concentration that was clearly lower than for any other of the tested biocides.
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| 9. |
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| 10. |
- Arrhenius, Åsa, 1973, et al.
(författare)
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Combined effects of antifoulants – synergistic, additive or antagonistic effects?
- 2010
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Ingår i: the 15th International Congress on Marine Corrosion and Fouling, 25-29 July 2010, Newcastle.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Antifoulants are often used in combinations in paints. A survey of the scientific literatures shows that the effects of such antifoulant combinations are often predictable with a reasonable accuracy by the classical mixture toxicity concepts of Concentration Addition (CA) and Independent Action (IA). However, some studies also reported mixture effects that were substantially higher (synergistic) or lower (antagonistic) than predicted by either CA or IA. We therefore systematically explored the frequency and quantitative importance of such interactions within a group of 6 antifoulants using settling and growth of marine periphytic communities as the endpoint. All 15 possible 2-compound combinations that can be composed from the pool of six antifoulants were experimentally tested in three different ratios per mixture and their observed toxicity was compared to the predictions by CA and IA. The results show that the toxicities of the mixtures in most cases are at least roughly in agreement with the predictions, but that in several cases antagonistic effects occurred, which were related to the mixture-ratio and concentrations applied. No cases of synergism were observed for any of the investigated combinations. Implications for paint production as well as for the environment will be discussed. This study is part of the Marine Paint research programme funded by MISTRA, the Swedish Foundation for Strategic Environmental Research.
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| 11. |
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| 12. |
- Arrhenius, Åsa, 1973, et al.
(författare)
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Effects of antimycotics and fungicides to limnic microbial biofilms – a case study of the run-off from a golf course
- 2016
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Ingår i: 4th Biofilm Workshop - Basis and application of biofilms to assess the effects of environmental change in aquatic ecosystems - Girona, 7-8 April 2016.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Antimycotic pharmaceuticals and fungicides are widely used for treating fungal infections in humans and animals and control pests in different areas and applications. They enter the aquatic environment either after passage through the body, or after being rinsed off from areas of application (skin, crops, farmland etc.). However, substantial knowledge gaps currently hamper a proper environmental risk assessment of the individual antimycotics and fungicides and their mixtures for marine and freshwater environments. Previously it has been shown that clotrimazole, a marine priority pollutant, affected sterol composition of marine microalgal communities already at 50 pmol/L which indicates effects at environmental concentrations. In this presentation we will discuss results from our work with limnic microbial biofilms and effects from antimycotics and fungicides individually and as mixtures. Endpoints include growth, pigment pattern, sterol composition, and species composition. Special focus will be on a case study from a Swedish golf course with a high usage of fungicides. Based on an analytical survey we prepared a worst-case-mixture study were we exposed biofilms in indoor microcosms for several days. Effects on growth and some shifts in microalgal species composition could be observed at concentrations relevant for the nearby golf area. Analysis of sterol composition and analytical confirmation of exposure concentrations are work in progress. The work is performed within the Swedish Formas-funded project “Aquatic Environmental Risk Assessment of Antimycotics”.
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| 13. |
- Arrhenius, Åsa, 1973, et al.
(författare)
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Effects of three antifouling agents on algal communities and algal reproduction: Mixture toxicity studies with TBT, Irgarol, and Sea-Nine
- 2006
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 50:3, s. 335-345
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Tidskriftsartikel (refereegranskat)abstract
- The toxicity of three antifoulants (Sea-Nine, Irgarol, and TBT) was determined individually and in mixtures in two tests with microalgae. Effects on periphyton community photosynthesis and reproduction of the unicellular green algae Scenedesmus vacuolatus were investigated. The tested antifoulants were highly toxic in both tests. Observed mixture toxicities were compared with predictions derived from two concepts: Independent Action (IA), assumed to be more relevant for the tested mixtures that were composed of dissimilarly acting substances, and Concentration Addition (CA), regarded as a reasonable worst-case approach in predictive mixture hazard assessment. Despite the corresponding mechanistic basis, IA failed to provide accurate predictions of the observed mixture toxicities. Results show the same pattern in both assays. Mixture effects at high concentrations were slightly overestimated and effects at low concentrations were slightly underestimated. Maximum observed deviations between observed and IA-predicted concentrations amount to a factor of 4. The suggested worst-case approach using CA was protective only in effect regions above 20%. Nevertheless, the application of any concept that accounts for possible mixture effects is more realistic than the present chemical-by-chemical assessment
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| 14. |
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| 15. |
- Arrhenius, Åsa, 1973, et al.
(författare)
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Marine Paint Optimisation: settling assays with marine periphyton communities and sea lettuce (Ulva lactuca)
- 2008
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Ingår i: The 14th International Congress on Marine Corrosion and Fouling, July 27-31, 2008, Kobe, Japan.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In the Marine Paint Optimisation project the major groups of fouling organisms will be studied. From each group of organisms one model organism was selected and used in settling assays to assess the efficacy of a number of individual antifoulants. A tentative list of existing and promising compounds include medetomidine, tolylfluanide, copper pyrithione, Sea-Nine, Irgarol, copper, Borocide, and Econea. Based on the produced data we will predict the joint effects of almost all possible combinations in terms of efficacy. The optimisation will be based both on high efficacy and low environmental risk. We will present and summarise the results from two settling assays with marine biofilms (microfouling) and the zoospores of the macroalga sea lettuce (Ulva lactuca). The microfoulers are important parts of the fouling community with a high number of different species and individuals which form the basis for all subsequent settlers. In this periphyton assay a multispecies microbial biofilm established in the field on Plexi glas (PMMA) are used to prepare an inoculum using a scrape, shake and sieve technique. Using this approach we include a large set of the potential species in the microbial fouling community. Ulva lactuca belongs to the most common family of fouling macroalgae. Thalli of Ulva lactuca were sampled in the field in September 2007, cultivated in the laboratory until further testing of the zoospores. Both assays are semistatic and run over three days and include both settling and growth. Efficacy data for a number of antifouling agents will be presented. This study is part of the Marine Paint research programme funded by MISTRA.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Arrhenius, Åsa, 1973, et al.
(författare)
-
Predictability of the mixture toxicity of 12 similarly acting congeneric inhibitors of photosystem II in marine periphyton and epipsammon communities
- 2004
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X. ; 68:4, s. 351-367
-
Tidskriftsartikel (refereegranskat)abstract
- Testing of single chemicals with single species is common ecotoxicological practice in contrast to contaminated environments where highly diverse biological communities are exposed to highly diverse mixtures of chemical compounds. We, therefore, investigated whether mixture toxicity approaches that have been used successfully for single species, might also be applied on a community level of biological complexity. Twelve inhibitors of photosystem II, selected by QSAR and chemometrical approaches as the structurally most similar from a congeneric group of phenylurea herbicides, were tested singly and as mixtures on two types of marine microalgal communities, periphyton and epipsammon. Inhibition of photosynthesis was measured in short-term tests using incorporation of radiolabelled carbon (14C) to estimate photosynthetic rates. Two basic concepts, concentration addition (CA) and independent action (IA), were used to predict the toxicities of the mixtures. Congeneric and similar-acting substances such as the phenylureas are expected to comply with CA rather than IA. The aim of the present study was to evaluate whether these concepts can be used to predict mixture toxicity also to periphyton and epipsammon photosynthesis, i.e. at the level of natural communities. We found that deviations between observed and predicted mixture toxicity were relatively small but that CA predictions were the more accurate ones. The predictions proved to be robust, when based on single substance information even from different seasons, years, and sites. We conclude that the concept of CA for predicting mixture toxicity applies also at the community level of algal testing; at least when a physiological short-term effect indicator is used that matches the mechanism of action of the substances
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| 20. |
- Arrhenius, Åsa, 1973, et al.
(författare)
-
Toxicity of the fungicide ketoconazole to freshwater microalgal communities
- 2015
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Ingår i: SETAC Europe 25th Annual Meeting, Barcelona Spain.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Antimycotic pharmaceuticals are widely used for treating fungal infections in humans and animals. They enter the aquatic environment either after passage through the body, or after being rinsed off if they are topically applied. However, substantial knowledge gaps currently hamper a proper environmental risk assessment of the individual antimycotics and their mixtures for marine and freshwater environments. Clotrimazole, a marine priority pollutant, affected sterol composition of marine microalgal communities already at 50 pmol/L which indicates effects already at environmental concentrations. In the present study we focus on ketoconazole (also an azole fungicide) and toxicity to freshwater microalgal communities. A concentration response curve was first established using pigment profiles (HPLC) as endpoint which resulted in an EC50 of around 1 micromol/L. During autumn 2014 we repeated the study but focused on the lower concentration range from 0.0001 to 1 micromol/L. Results on chlorophyll a show similar patterns as in the initial study. The experiments were finished during autumn 2014 and are currently under final evaluation and sterol analysis, species determinations and analytical confirmation of exposure concentrations are currently evaluated. The work is performed within the Swedish Formas-funded project “Aquatic Environmental Risk Assessment of Antimycotics”.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
- Backhaus, Thomas, 1967, et al.
(författare)
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SINGLE-SUBSTANCE AND MIXTURE TOXICITY OF FIVE PHARMACEUTICALS AND PERSONAL CARE PRODUCTS TO MARINE PERIPHYTON COMMUNITIES
- 2011
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268. ; 30:9, s. 2030-2040
-
Tidskriftsartikel (refereegranskat)abstract
- The single-substance and mixture toxicity of five pharmaceuticals and personal care products (fluoxetine, propranolol, triclosan, zinc-pyrithione, and clotrimazole) to marine microalgal communities (periphyton) was investigated. All compounds proved to be toxic, with median effective concentration values (EC50s) between 1,800 nmol/L (triclosan) and 7.2 nmol/L (Zn-pyrithione). With an EC50 of 356 nmol/L, the toxicity of the mixture falls into this span, indicating the absence of strong synergisms or antagonisms. In fact, a comparison with mixture toxicity predictions by the classical mixture concepts of concentration addition and independent action showed a good predictability in the upper effect range. However, the mixture provoked stimulating effects (hormesis) in the lower effect range, hampering the application of either concept. An independent repetition of the mixture experiment resulted in a principally similar concentration-response curve, again with clear hormesis effects in the lower range of test concentrations. However, the curve was shifted toward higher effect concentrations (EC50 1,070 nmol/L), which likely is due to changes in the initial species composition. Clear mixture effects were observed even when all five components were present only at their individual no-observed-effect concentrations (NOECs). These results show that, even with respect to mixtures of chemically and functionally dissimilar compounds, such as the five pharmaceuticals and personal care products investigated, environmental quality standards must take possible mixture effects from low-effect concentrations of individual compounds into consideration. Environ. Toxicol. Chem. 2011;30:2030-2040. (C) 2011 SETAC
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| 25. |
- Backhaus, Thomas, 1967, et al.
(författare)
-
Toxicity of a mixture of dissimilarly acting substances to natural algal communities: predictive power and limitations of independent action and concentration addition.
- 2004
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Ingår i: Environmental science & technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 38:23, s. 6363-70
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Tidskriftsartikel (refereegranskat)abstract
- Predictive studies of chemical mixtures are typically based on experiments with single species. To study the applicability of the concepts of independent action (IA) and concentration addition (CA) on a multispecies level, the carbon fixation of natural algal communities under toxicant exposure was studied. The presented study focused on a mixture of six dissimilarly acting substances. Conceptual reasoning as well as empirical evidence from single-species tests suggest that IA is more appropriate for this type of mixture. Nonetheless, the potential of CA was also investigated, to assess whether this concept may be applicable as a reasonable worst case prediction of mixture toxicities also on a community level. IA predicted the experimental EC50 precisely. CA underestimated the EC50 by a factor of only 1.4, although the shape of the predicted concentration-response curve was clearly different from experimental data. Hence, it can be concluded that the applicability of the concepts is not restricted to the level of single species. However, some limitations of both concepts became apparent, when stimulating (hormesis-like) effects were observed fo rtwo of the mixture components. These effects were also seen in the experimental mixture toxicity data but cannot be adequately modeled by either concept.
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| 26. |
- Bighiu, Maria, et al.
(författare)
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Pesticide Mixtures Cause Short-Term, Reversible Effects on the Function of Autotrophic Periphyton Assemblages
- 2020
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 39:7, s. 1367-1374
-
Tidskriftsartikel (refereegranskat)abstract
- In a laboratory experiment we investigated the effects of pesticide mixtures on the structure and function of freshwater biofilms, with focus on their photoautotrophic component. We identified 6 herbicides and 1 fungicide commonly found in Swedish streams at relatively high concentrations and created 3 ternary mixtures that were tested in concentration series ranging from observed environmental concentrations to up to 100 times higher. Biofilms were exposed to these pesticide mixtures for 8 d and then allowed to recover for another 12 d. Our results show a rapid and consistent inhibition of photosynthesis after just 24-h exposure to the highest test concentration of pesticides, as well as in some treatments with lower concentrations (i.e., 10 times the environmental level), on exposure. Interestingly, the observed effects were reversible because biofilm photosynthesis recovered rapidly and completely in clean media in all but one treatment. In contrast to the functional response, no effects were observed on the algal assemblage structure, as assessed by diagnostic pigments. We conclude that the pesticide mixtures induce a rapid but reversible inhibition of photosynthesis, without short-term effects on biofilm structure. Environ Toxicol Chem 2020;00:1-8. (c) 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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| 27. |
- Blanck, Hans, 1950, et al.
(författare)
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Multiple effect thresholds and pollution-induced community tolerance in marine periphyton communities exposed to the antifouling agent DCOIT (Sea-Nine 211).
- 2005
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Ingår i: SETAC Europe 15th Annual Meeting, 22-26 May 2005, Lille , France.
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Konferensbidrag (refereegranskat)abstract
- Sea-Nine 211 is an antifouling agent with the active ingredient 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one (DCOIT). Compounds in the Kathon class of biocides contain a reactive sulfur atom suggested to target disulfide bridges of proteins. This causes formation of RS∙ radicals that attack new proteins and form new RS∙ radicals in a cascade reaction. This has the potential to affect and inhibit a variety of enzymatic cellular reactions. We hypothesise that this process, although not sufficiently studied, might also explain the extreme toxicity and rapid degradation of DCOIT in the presence of biota. An unusual response pattern among microalgae was revealed when periphyton communities were established in flow-through marine microcosm under DCOIT exposure for three weeks; biomass-related variables (chlorophyll a and primary production) showed effects alternating with recovery in the concentration gradient. These events coincided with at least three toxicant-induced successions (TIS) that appeared to be clearly separated from each other (approximately by a factor 100 on the concentration scale). The first TIS occurred at very low concentrations of DCOIT (0.007 nM) and was accompanied by a small increase in community tolerance. At slightly higher concentrations this PICT signal disappeared and PICT was only observed again at 1 to 5 nM, now accompanied by a second much stronger replacement of species. A third major shift in species composition occurred at 10 to100 nM where PICT continued to increase. Between the shifts in algal species, biomass tended to increase until further loss of dominant species was observed. We suggest that the observed multiple effect thresholds are due to differences in sensitivity either between biochemical target processes or between target species within the periphyton community.
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| 28. |
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| 29. |
- Brosché, Sara, 1978, et al.
(författare)
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Effects of two realistic pharmaceutical mixtures on natural freshwater periphyton communities
- 2007
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Ingår i: Society of Environmental Toxicology and Chemistry Europe annual meeting, 20-24 May 2006, Porto, Portugal.
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Konferensbidrag (refereegranskat)abstract
- During the last decade pharmaceuticals have been established as an important class of environmental pollutants. Main route of entry into the environment is from their regular use, which makes effluents from sewage treatment plants important sources of pollution. According to data from standard ecotoxicological tests, pharmaceuticals rarely pose an immediate risk at environmentally realistic concentrations. In reality though, pharmaceuticals act as mixtures on whole biological communities. Whether, and to what extent ecological effects can be expected under these circumstances is unknown. Hence we investigated the effects of two mixtures consisting of 15-20 pharmaceuticals on natural freshwater periphyton communities. The mixture compositions were based on effluent data from two sewage treatments plants, Ryaverket (Göteborg, Sweden) and Châtillon-sur-Chalaronne (Lyon, France). Effects on periphytic bacteria were measured as changes in metabolic diversity (Ecolog®). For the algal part of the communities, changes in pigment pattern and species composition were measured. Clear community-level effects were observed for the two mixtures
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| 30. |
- Eriksson, Martin, 1970, et al.
(författare)
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Long-term effects of the antibacterial agent triclosan on marine periphyton communities
- 2015
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 34:9, s. 2067-2077
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Tidskriftsartikel (refereegranskat)abstract
- Triclosan is a widely used antibacterial agent that has become a ubiquitous contaminant in freshwater, estuary, and marine environments. Concerns about potential adverse effects of triclosan have been described in several recent risk assessments. Its effects on freshwater microbial communities have been well studied, but studies addressing effects on marine microbial communities are scarce. In the present study, the authors describe short- and long-term effects of triclosan on marine periphyton (microbial biofilm) communities. Short-term effects on photosynthesis were estimated after 60min to 210min of exposure. Long-term effects on photosynthesis, chlorophyll a fluorescence, pigment content, community tolerance, and bacterial carbon utilization were studied after exposing periphyton for 17d in flow-through microcosms to 0.316nM to 10000nM triclosan. Results from the short-term studies show that triclosan is toxic to periphyton photosynthesis. Half maximal effective concentration (EC50) values of 1080nM and 3000nM were estimated using (CO2)-C-14-incorporation and pulse amplitude modulation (PAM) fluorescence measurements, respectively. After long-term triclosan exposure in flow-through microcosms, photosynthesis estimated using PAM fluorometry was not inhibited by triclosan concentrations up to 1000nM but instead increased with increasing triclosan concentration. Similarly, at exposure concentrations of 31.6nM and higher, triclosan caused an increase in photosynthetic pigments. At 316nM triclosan, the pigment amounts were increased by a factor of 1.4 to 1.9 compared with the control level. Pollution-induced community tolerance was observed for algae and cyanobacteria at 100nM triclosan and higher. Despite the widespread use of triclosan as an antibacterial agent, the compound did not have any effects on bacterial carbon utilization after long-term exposure.
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| 31. |
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| 32. |
- Inostroza, Pedro, et al.
(författare)
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Target Screening of Chemicals of Emerging Concern (CECs) in Surface Waters of the Swedish West Coast
- 2023
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Ingår i: Data. - 2306-5729. ; 8:6
-
Tidskriftsartikel (refereegranskat)abstract
- The aquatic environment faces increasing threats from a variety of unregulated organic chemicals originating from human activities, collectively known as chemicals of emerging concern (CECs). These include pharmaceuticals, personal-care products, pesticides, surfactants, industrial chemicals, and their transformation products. CECs enter aquatic environments through various sources, including effluents from wastewater treatment plants, industrial facilities, runoff from agricultural and residential areas, as well as accidental spills. Data on the occurrence of CECs in the marine environment are scarce, and more information is needed to assess the chemical and ecological status of water bodies, and to prioritize toxic chemicals for further studies or risk assessment. In this study, we describe a monitoring campaign targeting CECs in surface waters at the Swedish west coast using, for the first time, an on-site large volume solid phase extraction (LVSPE) device. We detected up to 80 and 227 CECs in marine sites and the wastewater treatment plant (WWTP) effluent, respectively. The dataset will contribute to defining pollution fingerprints and assessing the chemical status of marine and freshwater systems affected by industrial hubs, agricultural areas, and the discharge of urban wastewater. Dataset: 10.5281/zenodo.7845557 Dataset License: CC-BY-NC-SA 4.0
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| 33. |
- Menz, J., et al.
(författare)
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Antimicrobial activity of pharmaceutical cocktails in sewage treatment plant effluent – An experimental and predictive approach to mixture risk assessment
- 2017
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 231, s. 1507-1517
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Tidskriftsartikel (refereegranskat)abstract
- Municipal wastewater contains multi-component mixtures of active pharmaceutical ingredients (APIs). This could shape microbial communities in sewage treatment plants (STPs) and the effluent-receiving ecosystems. In this paper we assess the risk of antimicrobial effects in STPs and the aquatic environment for a mixture of 18 APIs that was previously detected in the effluent of a European municipal STP. Effects on microbial consortia (collected from a separate STP) were determined using respirometry, enumeration of culturable microorganisms and community-level physiological profiling. The mixture toxicity against selected bacteria was assessed using assays with Pseudomonas putida and Vibrio fischeri. Additional data on the toxicity to environmental bacteria were compiled from literature in order to assess the individual and expected joint bacterial toxicity of the pharmaceuticals in the mixture. The reported effluent concentration of the mixture was 15.4 nmol/l and the lowest experimentally obtained effect concentrations (EC10) were 242 nmol/l for microbial consortia in STPs, 225 nmol/l for P. putida and 73 nmol/l for V. fischeri. The lowest published effect concentrations (EC50) of the individual antibiotics in the mixture range between 15 and 150 nmol/l, whereas 0.9–190 μmol/l was the range of bacterial EC50 values found for the non-antibiotic mixture components. Pharmaceutical cocktails could shape microbial communities at concentrations relevant to STPs and the effluent receiving aquatic environment. The risk of antimicrobial mixture effects was completely dominated by the presence of antibiotics, whereas other pharmaceutical classes contributed only negligibly to the mixture toxicity. The joint bacterial toxicity can be accurately predicted from the individual toxicity of the mixture components, provided that standardized data on representative bacterial strains becomes available for all relevant compounds. These findings argue for a more sophisticated bacterial toxicity assessment of environmentally relevant pharmaceuticals, especially for those with a mode of action that is known to specifically affect prokaryotic microorganisms. Pharmaceutical cocktails pose a risk to microbial communities in sewage treatment plants and the aquatic environment. © 2017 Elsevier Ltd
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| 34. |
- Porsbring, Tobias, 1974, et al.
(författare)
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Effects of clotrimazole on the pigment composition of marine periphyton communities for use in predictive ecological mixture toxicity assessment
- 2006
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Ingår i: SETAC Europe 16th Annual Meeting, The Hague, The Netherlands.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Clotrimazole is a pharmaceutic fungicide classified as persistent and toxic according to EU Technical Guidance Document, and reaches the marine environment mainly from municipal waste water treatment plants together with several other pollutants. In a project to assess mixture toxicity of pharmaceuticals on microbial communities, clotrimazole effects on the development of periphyton were measured in two independent SWIFT tests in 2004 and 2005. Microalgal communities were precolonised in the Gullmar fjord on the west coast of Sweden on 1.5 cm2 glass discs. Following a 96h incubation in a concentration series of clotrimazole, periphyton pigment profiles were analysed using HPLC, and effects were calculated as Bray-Curtis dissimilarity indices. In both tests, a clotrimazole concentration of 11 microg/l had a significant effect on pigment composition with a NOEC of 3.45 microg/l (nominal). This indicates an approximately 5 times higher clotrimazole toxicity to algae than single species data, although comparisons to PEC values suggests a low risk for marine algae. However, the importance of clotrimazole for the risks of mixtures is further researched.
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| 35. |
- Porsbring, Tobias, 1974, et al.
(författare)
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Observed and predicted combination effects of the antifouling agents irgarol 1051, TBT and Sea-Nine TM 211 on the structural and functional properties of marine microalgal communities
- 2004
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Ingår i: SETAC Europe 14th Annual meeting, Prague, Czech Republic.
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Konferensbidrag (refereegranskat)abstract
- Risks of mixtures of pollutants in ecosystems cannot be assessed when chemicals are treated as acting alone. This issue is increasingly recognised, but valid and useful tools for considering mixtures are needed. However the concepts Concentration Addition (CA) and Independent Action (IA) has been shown to have potential for predicting mixture toxicities. With the aim to evaluate CA and IA under ecologically realistic conditions the antifouling agents irgarol 1051, Sea-NineTM211 and TBT were tested singly and in an equieffective mixture on marine periphyton communities in a semistatic SWIFT test. Periphyton was established on 1.5 cm2 glass discs submerged in the Gullmar fjord, Sweden and then incubated for 96 h under constant light and temperature in a medium of GF/F filtered seawater with added phosphate, nitrate and toxicant(s). Effects were then quantified by comparing analysed pigment and species composition between treatments and controls using Bray-Curtis dissimilarity index. The observed mixture effect on species composition was in perfect agreement with CA, while IA was accurate for lower observed effects but overestimated the toxicity at higher. Using pigments for predictions was found to be sensitive as this reflected lower observed effects on species composition. IA and CA are beleived to apply for mixtures of toxicants with dissimilar and similar biochemical mechanisms of action respectively and as irgarol, TBT and Sea-Nine are dissimilarly acting the most accurate prediction should be IA. However biochemical modes of action may become less relevant for predictions in an ecological context where a mode of action could be defined more by impacts on specific species and trophic levels. Results indicates that risks of mixtures should be considered and are predictable.
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| 36. |
- Porsbring, Tobias, 1974, et al.
(författare)
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The SWIFT periphyton test for high-capacity assessments of toxicant effects on microalgal community development
- 2007
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Ingår i: Journal of Experimental Marine Biology and Ecology. - : Elsevier BV. - 0022-0981. ; 349:2, s. 299-312
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Tidskriftsartikel (refereegranskat)abstract
- The SWIFT periphyton test was developed as a simple and high-capacity approach for assessing toxicant effects on the succession of natural communities. Attached microbial communities (periphyton) were developed over a 7 to 9 day period on artificial glass substratum submerged at sea and then transferred to a controlled indoor environment for 4 day incubation with toxicants. Added nutrients and continuous light over the test phase facilitated periphyton growth and consequently accelerated the rate of ecological succession. The structure and physiology of the algal community can be analysed using any suitable method. In this paper we suggest HPLC-based analyses of community pigment profiles as a fast and less laborious alternative to e.g. microscopic species counts. Several crucial properties of the SWIFT test were evaluated: the biological complexity of the periphyton used for testing, the consequences of the 4 day incubation under artificial conditions, toxicant effects on community structure and the feasibility of using pigment profiles as descriptors of periphyton communities. The performance of SWIFT as an ecotoxicological test system was evaluated using the three antifouling agents irgarol 105 1, Sea-Nine(TM) 211 (DCOIT) and TBT (tri-n-butyltin). Periphyton communities used in SWIFT were of high taxonomic richness and diversity, and there were no indications for adverse changes in these characteristics over the 4 day test phase. Community pigment profiles discriminated between different communities with a resolution equally good to microscopic species counts. Comparative concentration-response studies with a two-week microcosm experiment and SWIFT revealed similar concentration and toxicant-dependent shifts in the relative abundances of species. This shows that despite the methodological simplifications in SWIFT, crucial ecological features such as competition and species sensitivity profiles were still the major factors determining the ecological succession under toxicant exposure. The sensitivity of SWIFT was equal to that of the flow-through microcosms for irgarol and TBT and lower for DCOIT, probably because of the semi-static test regime in SWIFT. Species composition and pigment profiles over seasons, together with toxicant-induced effects on the diatom xantophyll cycle and the relative content of beta-carotene, shows that pigment profiles reflect both the taxonomy and the physiology of a community. Similar to encountered changes in species composition, pigment profiles were specifically influenced by the tested toxicants. (C) 2007 Elsevier B.V. All rights reserved.
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| 37. |
- Tlili, Ahmed, et al.
(författare)
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Addendum to Tolerance Patterns in Stream Biofilms Link Complex Chemical Pollution to Ecological Impacts
- 2021
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 55:1
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Tidskriftsartikel (refereegranskat)abstract
- Following publication of our paper, we were made aware that we might not have sufficiently pointed out the potential role that microorganisms released with wastewater effluents could play in the increased tolerance of downstream biofilms toward micropollutants. Indeed, a large survey in 23 wastewaterimpacted streams, including the three sampling sites investigated in our study, showed that downstream bacterialcommunity profiles in the water column were a mixture between the upstream and the effluent.1 Whether these microorganisms go from a planktonic into a benthic biofilm state and play a role in the tolerance to micropollutants remains unclear. Nevertheless, it is plausible that suchmicroorganisms might have developed a tolerance to micropollutants in the wastewater treatment plants (WWTP) before their release into the streams. Mußmann et al.2 have shown that, among all identified nitrifying bacteria in the WWTP effluent, only one taxa preferentially added to the downstream biofilm community whereas the others did not. Similarly, Chonova3 showed that less than 5% and not the most abundant bacterial taxa were found in the biofilms downstream of urban and hospital WWTP. Even if actively colonizing downstream biofilms, monitoring the diversity profile of these microorganisms alone does not answer the question whether they contribute to the community tolerance to micropollutants. Therefore, controlled experiments focusing on both benthic bacterial and algal communities are needed to address this issue.
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| 38. |
- Tlili, A., et al.
(författare)
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Tolerance Patterns in Stream Biofilms Link Complex Chemical Pollution to Ecological Impacts
- 2020
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Ingår i: Environmental Science & Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 54:17, s. 10735-10743
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Tidskriftsartikel (refereegranskat)abstract
- Preventing and remedying fresh waters from chemical pollution is a fundamental societal and scientific challenge. With other nonchemical stressors potentially co-occurring, assessing the ecological consequences of reducing chemical loads in the environment is arduous. In this case study, we comparatively assessed the community structure, functions, and tolerance of stream biofilms to micropollutant mixtures extracted from deployed passive samplers at wastewater treatment plant effluents. These biofilms were growing up- and downstream of one upgraded and two nonupgraded wastewater treatment plants before being sampled for analyses. Our results showed a substantial decrease in micropollutant concentrations by 85%, as the result of upgrading the wastewater treatment plant at one of the sampling sites with activated carbon filtration. This decrease was positively correlated with a loss of community tolerance to micropollutants and the recovery of the community structure downstream of the effluent. On the other hand, downstream biofilms at the nonupgraded sites displayed higher tolerance to the extracts than the upstream biofilms. The observed higher tolerance was positively linked to micropollutant levels both in stream water and in biofilm samples, and to shifts in the community structure. Although more investigations of upgraded sites are needed, our findings point toward the suitability of using community tolerance for the retrospective assessment of the risks posed by micropollutants, to assess community recovery, and to relate effects to causes in complex environmental conditions.
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| 39. |
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| 40. |
- Wendt, Ida, 1981, et al.
(författare)
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The toxicity of the three antifouling biocides DCOIT, TPBP and medetomidine to the marine pelagic copepod Acartia tonsa
- 2016
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Ingår i: Ecotoxicology. - : Springer Science and Business Media LLC. - 0963-9292 .- 1573-3017. ; 25:5, s. 871-879
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Tidskriftsartikel (refereegranskat)abstract
- © 2016 Springer Science+Business Media New York Copepods, the largest group of pelagic grazers, are at risk from exposure to antifouling biocides. This study investigated the toxicity of the antifouling biocides 4,5-dichloro-2-octyl-1,2-thiazol-3(2H)-one (DCOIT), triphenylborane pyridine (TPBP) and 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (medetomidine) to the copepod Acartia tonsa, using mortality and egg production as endpoints. The toxicity ranking for mortality was as follows: DCOIT (LC50 57 nmol l−1) = TPBP (LC50 56 nmol l−1) > medetomidine (LC50 241 nmol l−1). Egg production was more sensitive than mortality to TPBP (EC50 3.2 nmol l−1), while DCOIT and medetomidine inhibited egg production at roughly the same concentrations (72 and 186 nmol l−1 respectively). Furthermore, TPBP seems to affect egg hatching directly which was not the case for DCOIT and medetomidine. DCOIT and medetomidine might pose an environmental risk as they have been reported to occur in different exposure scenarios or analytical surveys at concentrations only 2–3 times lower than the respective EC10. Reported environmental concentrations of TPBP are few but clearly lower than the EC10 values reported here, suggesting current risk of TPBP to copepods to be moderate.
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