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Adverse outcome pathways (AOPs) for radiation-induced reproductive effects in environmental species: state of science and identification of a consensus AOP network
Get PDFReproductive effects of ionizing radiation in organisms have been observed under laboratory and field conditions. Such assessments often rely on associations between exposure and effects, and thus lacking a detailed mechanistic understanding of causality between effects occurring at different levels of biological organization. The Adverse Outcome Pathway (AOP), a conceptual knowledge framework to capture, organize, evaluate and visualize the scientific knowledge of relevant toxicological effects, has the potential to evaluate the causal relationships between molecular, cellular, individual, and population effects. This paper presents the first development of a set of consensus AOPs for reproductive effects of ionizing radiation in wildlife. This work was performed by a group of experts formed during a workshop organized jointly by the Multidisciplinary European Low Dose Initiative (MELODI) and the European Radioecology Alliance (ALLIANCE) associations to present the AOP approach and tools. The work presents a series of taxon-specific case studies that were used to identify relevant empirical evidence, identify common AOP components and propose a set of consensus AOPs that could be organized into an AOP network with broader taxonomic applicability.publishedVersio
Tilpasning av en kvantitativ PCR metode for deteksjon av Prymnesium parvum i sjøvann
Get PDFProsjektleder Trine DaleEt fellestrekk ved flere av de algene som skaper problemer i akvakultur er at den konvensjonelle metoden for deteksjon og mengdebestemmelse er mikroskop. Når det gjelder skadelige alger er mange arter små og skjøre og blir lett ødelagt ved konservering. Flere arter er vanskelige å identifisere og identifisering krever kvalifisert personell med mye praktisk erfaring. Realtime og kvantitativ real-time PCR (qPCR) metodene er blant de alternative metodene som har blitt testet i overvåkningsøyemed. Helt fra slutten av 1980 tallet har blomstringer av svepeflagellaten Prymnesium parvum vært et problem i Hylsfjorden og tilgrensende fjordsystem, hvor den periodevis har forårsaket betydelig dødelighet hos oppdrettsfisk. Med utgangspunkt i publiserte protokoller har vi tilpasset/utviklet assays for identifisering av P. parvum i vannprøver. I 2018 ble protokollen testet ut i overvåkningsprogrammet som Grieg Seafood Rogaland kjører hver sommer i Hylsfjorden. Programmet av ukentlige vannprøver fra to dyp i perioden mai til desember. Det antydes en deteksjonsgrense på 1000 celler/L ved bruk av denne protokollen. Det ble detektert forekomster av P. parvum i fire prøver med qPCR metoden. P. parum ble ikke detektert med mikroskopi i noen prøver dette året. Lav deteksjonsgrense er viktig fordi det kan avdekke en blomstring som er under oppbygging og dermed gi oppdrettere bedre tid til å iverksette tiltak.publishedVersio
Utredning: Organiseringsmodell for Alna - effektiv og langsiktig organisering for samordnet og kunnskapsbasert tiltaksarbeid i et byvassdrag
Get PDFProsjektleder/Hovedforfatter Ingrid NesheimRapporten er sluttproduktet for et prosjekt om utredning av organiseringsmodeller for samordnet og kunnskapsbasert tiltaksarbeid i og langs Alnavassdraget. Utarbeidelsen av rapporten bygger på informasjonsinnhenting gjennom evalueringsrapporter som har adressert organisering for samordning vertikalt og horisontalt nivå, og andre større prosjekter. Rapporten presenterer et forslag til organisering av en satsning for restaurering av Alna, som kan oppnå synergier mellom sektorer på statlig og kommunalt nivå.publishedVersio
Tiltaksorientert vannovervåking etter vannforskriften i Karmsundet. Undersøkelser av blåskjell, sedimenter, bløtbunnsfauna og fjæresone i 2021.
Get PDFProsjektleder Merete SchøyenNIVA har utført tiltaksorientert overvåking i henhold til vannforskriften i Karmsundet i 2021. Ved syv blåskjellstasjoner og åtte sedimentsstasjoner har det blitt analysert for et utslippsrelevant utvalg av de prioriterte stoffene kvikksølv (Hg), bly (Pb), kadmium (Cd), nikkel (Ni), en rekke PAH-forbindelser og PFOS. Det ble også analysert for de vannregionspesifikke stoffene arsen (As), krom (Cr), kobber (Cu), sink (Zn), en rekke PAH-forbindelser og PFOA. Det har blir gjort undersøkelser av bløtbunnsfauna ved seks stasjoner og fjæresone ved to stasjoner. For de prioriterte stoffene i blåskjell var det overskridelser av grenseverdier (EQS) for PAH-forbindelsene benzo(a)pyren og fluoranten på stasjon KB6-Høgevarde, og kjemisk tilstand var «ikke god». For de andre seks blåskjellstasjonene var kjemisk tilstand «god». For de prioriterte stoffene i sedimenter var det overskridelser for Hg og flere PAH-forbindelser, og kjemisk tilstand var «ikke god» på seks av åtte stasjoner. Undersøkelsen av bløtbunnsfauna viste at den økologiske tilstanden var «god» på tre stasjoner og «dårlig» på tre stasjoner. Undersøkelsen av makroalgevegetasjonen i fjæresonen viste «god» økologisk tilstand på de to stasjonene som var undersøkt.publishedVersio
Assessing Stress Resilience After Smolt Transportation by Waterborne Cortisol and Feeding Behavior in a Commercial Atlantic Salmon (Salmo salar) Grow-Out Recirculating Aquaculture System
Get PDFSampling protocols and water quality sensors have been developed to assess fish health and welfare in recirculating aquaculture systems (RASs). Still, the use of fish-based non-invasive welfare indicators, reflecting the physiological state of the fish, is limited in this type of system. Cortisol, the major stress-coping hormone in fish, diffuses through the gills. Consequently, waterborne cortisol is a potential fish-based non-invasive welfare indicator in RAS. However, its use in commercial rearing systems is sparse. In this study, we evaluated water cortisol levels and feeding behavior as welfare indicators of newly inserted smolt in a commercial RAS for harvest size Atlantic salmon. The RAS consisted of two parallel fish rearing raceways, raceways 1 and 2, sharing the same water treatment with common outlets and inlets. The smolts were inserted in raceway 1 while salmon that have been in the system for 6 months or more were kept in raceway 2. The smolt insertion period was 3 days. Samples for water cortisol levels were withdrawn the day before, 1 and 3 days after the smolt insertion period. Smolt insertion resulted in elevated water cortisol concentrations in the entire system, with the highest values in raceway 1, one day after smolt insertion. Estimated cortisol production in newly inserted smolt decreased over time, was similar to what has been reported in salmon adapting to experimental tanks. Feeding behavior indicated that the appetite was not fully resumed in the newly inserted smolts, while the appetite of fish in raceway 2 was unaffected by smolt insertion. These results, obtained in a highly intensive commercial RAS, suggest that waterborne cortisol together with feeding behavior can be used as indicators for adaptive processes associated with stress resilience in farmed fish. Thus, they are promising non-invasive indicators for assessing the impact of potential stressors on fish welfare in this type of rearing system.publishedVersio
Økokyst – DP Skagerrak. Årsrapport 2020.
Get PDFRevidert versjon av rapport 7627-2021.Overvåkingsprogrammet "Økosystemovervåking i Kystvann – Økokyst" har til hensikt å overvåke miljøtilstanden i utvalgte områder langs norskekysten i henhold til vannforskriften. Delprogram Skagerrak omfatter 14 vannforekomster lokalisert i Ytre Oslofjord og Grenlands- fjordene. Samlet tilstand i vannforekomstene varierte fra “dårlig” til “god” tilstand i 2020. Blant undersøkte biologiske kvalitetselementer, er det særlig makroalge-samfunnene som viser en negativ trend. Totalt fem av åtte makroalgestasjoner oppnår «moderat» tilstand i 2020.publishedVersio
Effects of Polyester Fibers and Car Tire Particles on Freshwater Invertebrates
Get PDFMicroplastic ingestion has been shown for various organisms, but knowledge of the potential adverse effects on freshwater invertebrates remains limited. We assessed the ingestion capacity and the associated effects of polyester fibers (26–5761 µm) and car tire particles (25–75 µm) on freshwater invertebrates under acute and chronic exposure conditions. A range of microplastic concentrations was tested on Daphnia magna, Hyalella azteca, Asellus aquaticus, and Lumbriculus variegatus using water only (up to 0.15 g/L) or spiked sediment (up to 2 g/kg dry wt), depending on the habitat of the species. Daphnia magna did not ingest any fibers, but low levels of fibers were ingested by all tested benthic invertebrate species. Car tire particle ingestion rose with increasing exposure concentration for all tested invertebrates and was highest in D. magna and L. variegatus. In most cases, no statistically significant effects on mobility, survival, or reproductive output were observed after acute and chronic exposure at the tested concentrations. However, fibers affected the reproduction and survival of D. magna (no-observed-effect concentration [NOEC]: 0.15 mg/L) due to entanglement and limited mobility under chronic conditions. Car tire particles affected the reproduction (NOEC: 1.5 mg/L) and survival (NOEC: 0.15 mg/L) of D. magna after chronic exposure at concentrations in the same order of magnitude as modeled river water concentrations, suggesting that refined exposure and effect studies should be performed with these microplastics. Our results confirm that microplastic ingestion by freshwater invertebrates depends on particle shape and size and that ingestion quantity depends on the exposure pathway and the feeding strategy of the test organism.publishedVersio
Empirical support for sequential imprinting during downstream migration in Atlantic salmon (Salmo salar) smolts
Get PDFThe precise homing of Atlantic salmon to their natal river and spawning grounds is the foundation for locally adapted genetically differentiated populations across rivers or across river sections. A sequential imprinting hypothesis states that salmon smolts may imprint on environmental clues along the outward migration route and then use this in reverse order to direct the spawning migration later in life. In this study, we provide empirical support for this hypothesis. PIT-tagged wild Atlantic salmon using a 2 km hydropower tunnel as downstream migrating smolts had a 18% (1SW) and 23% (2SW) lower probability of successfully migrating through the parallel river stretch as adult spawners compared to spawners that migrated through the same river stretch as smolts. These findings highlight how a fine-scale riverine migration route may be imprinted in wild Atlantic salmon smolts. From an applied perspective, these results stress the importance of not depriving smolts from parts of their migration route to ensure successful return of adults to their natal spawning grounds.publishedVersio
What Are Lake Beaches Made of? An Assessment of Plastic Beach Litter on the Shores of Como Bay (Italy)
Get PDFPlastic waste dispersion is a well-recognized environmental threat, despite continuous efforts towards improving waste disposal management over the last few decades. Plastic litter is known to strongly impact upon water bodies and shorelines, affecting the health of ecosystems and impacting upon the aesthetic value of sites. Moreover, plastic waste that is abandoned on beaches contributes towards different degradation processes that potentially lead to the formation of secondary microplastics (MPs), with likely cascade effects upon the whole ecosystem. In this view, this study aims to characterize the plastic beach litter found on the shores of the western basin of Como Lake (Italy) to better understand the origin of MPs in littoral sediments, including the recognition of object typologies and the chemical characterization of polymers using Fourier-transformed infrared analysis (FTIR). The results highlighted that the most abundant polymers on beaches are polypropylene (PP) and polyethylene (PE), representing 73% of the collected polymers. This confirms that floating, low-density polymers are more likely to accumulate on beaches. Moreover, almost 66% of litter is represented by commonly used manufactured items (disposable objects, packaging, and everyday items). This evidence, combined with the analysis of the main environmental features of the sampling sites (the main winds, distance to urban areas, and the presence of tributaries) indicate that abundance of beached litter is mainly linked to beach accessibility and the local winds. These results highlight that multiple factors affect the environmental fate of plastic litter and give insights into the assessment of secondary microplastics in beach sediments.publishedVersio
Monitoring ocean water quality by deployment of lumpfish (Cyclopterus lumpus) eggs: In situ bioaccumulation and toxicity in embryos
Get PDFFish embryos can bioaccumulate and are particularly sensitive to a wide range of contaminants, which makes them suitable sentinels for environmental biomonitoring. However, fish embryos are very rarely utilized in environmental monitoring surveys, possibly due to their fragility and seasonality. In the present work, we assessed the applicability of caged lumpfish (Cyclopterus lumpus) eggs for in situ biomonitoring of exposure and effects of organic contaminants focusing on polyaromatic hydrocarbons and phenolic compounds. Fertilized eggs (1 dpf) were transplanted for 17–19 days at different locations that differed in terms of contaminant load, depths and weather conditions, namely at three stations close to the city of Trondheim (two harbour areas and a one in the Fjord) and three stations at a coastal aquaculture facility. High survival upon retrieval after deployment showed that lumpfish eggs are relatively robust and survive encaging in different environments. Bioaccumulation of organic contaminants (PAHs and phenolic compounds) was measured and potential effects on hatching, development, survival and larvae morphometry were determined. Chemical analyses showed that especially PAHs were effectively accumulated in eggs in contaminated sites, with concentrations of ƩPAHs being 15 – 25 times higher in harbour areas compared to those at the aquaculture facility. A higher incidence of embryonic deformations was observed in the most polluted deployment location, but larvae morphometry revealed no evidence of toxicity related to pollutant body burden. In conclusion, the in-situ exposure method was proven to work well, making it attractive for implementations in environmental monitoring programs.publishedVersio