OSPAR-metodikk og plastanalyse av strandsøppel fra Nordre Langåra og Akerøya

Prosjektleder Inger Lise Nerland BråteMer strandsøppel ble registrert på Akerøya (fra 2018) fra Ytre Hvaler, enn Nordre Langåra (fra 2019) fra Indre Oslofjord, men det er usikkert om disse tallene er robuste nok til å konkludere med at Akerøya har større plastbelastning enn Nordre Langåra. Mesteparten av avfallet, målt i antall, som ble funnet i både indre og ytre Oslofjord var fiskerirelatert, og mye av dette var såkalte «dollyropes». Den nest mest vanlige kategorien var uidentifiserbare plastbiter som trolig har mange diffuse kilder. Det var polyetylen (PE) og polypropylen (PP) som dominerte på begge strendene. Dette kan skyldes at disse polymertypene er de mest produserte og brukte plasttypene, samt at de som oftest flyter i sjøvann. Mesteparten av søpla fra ytre Hvaler ble antatt å ha norsk opphav, men av det utenlandske avfallet antas det å være bidrag fra 43 land. OSPAR-metodikken er svært verdifull og på nåværende tidspunkt det beste verktøyet vi har for å registrere strandsøppel for å se på mengde og komposisjon av strandsøppel i Nordøst-Atlanteren. Det er likevel flere forbedringspunkter ved OSPAR-metodikken; blant annet foreslås det å inkludere vekt for de ulike kategoriene, samt inter-kalibrere rydding mellom strender for å harmonisere metoden.Handelens MiljøfondpublishedVersio

Innovative reference materials for method validation in microplastic analysis including interlaboratory comparison exercises

Reference materials (RMs) are vital tools in the validation of methods used to detect environmental pollutants. Microplastics, a relatively new environmental pollutant, require a variety of complex approaches to address their presence in environmental samples. Both interlaboratory comparison (ILC) studies and RMs are essential to support the validation of methods used in microplastic analysis. Presented here are results of quality assurance and quality control (QA/QC) performed on two types of candidate microplastic RMs: dissolvable gelatin capsules and soda tablets. These RMs have been used to support numerous international ILC studies in recent years (2019–2022). Dissolvable capsules containing polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene (PE), and polystyrene (PS), in different size fractions from 50 to 1000 µm, were produced for one ILC study, obtaining relative standard deviation (RSD) from 0 to 24%. The larger size fraction allowed for manual addition of particles to the capsules, yielding 0% error and 100% recovery during QA/QC. Dissolvable capsules were replaced by soda tablets in subsequent ILC studies and recovery test exercises because they were found to be a more reliable carrier for microplastic RMs. Batches of soda tablets were produced containing different single and multiple polymer mixtures, i.e., PE, PET, PS, PVC, polypropylene (PP), and polycarbonate (PC), with RSD ranging from 8 to 21%. Lastly, soda tablets consisting of a mixture of PE, PVC, and PS (125–355 µm) were produced and used for recovery testing during pretreatment of environmental samples. These had an RSD of 9%. Results showed that soda tablets and capsules containing microplastics >50 µm could be produced with sufficient precision for internal recovery tests and external ILC studies. Further work is required to optimize this method for smaller microplastics (< 50 µm) because variation was found to be too large during QA/QC. Nevertheless, this approach represents a valuable solution addressing many of the challenges associated with validating microplastic analytical methods.publishedVersio

Occurrence of pearls in mussels (Mytilus spp.) from the Norwegian coast

Project manager Inger Lise Nerland BråteMussels (Mytilus spp.) from the Norwegian coast produce pearls, up to as many >360 pearls per individual, and it seems to be a southern-northern gradient with more pearls in mussels from the south than from the north. Out of the 280 mussels studied, nearly 2000 pearls were found, and the mussels producing pearls were all >4 cm. Size and condition index did correlate with the pearl frequency, while microplastics did not. Mussel health is important to study as they are important actors in the coastal ecosystem, as bioindicators for environmental monitoring, as a food source as well as the recent reports on changes in their distribution across the Norwegian coast.Norwegian Environment AgencypublishedVersio

Occurrence of pearls in mussels (Mytilus spp.) from the Norwegian coast

Mussels (Mytilus spp.) from the Norwegian coast produce pearls, up to as many >360 pearls per individual, and it seems to be a southern-northern gradient with more pearls in mussels from the south than from the north. Out of the 280 mussels studied, nearly 2000 pearls were found, and the mussels producing pearls were all >4 cm. Size and condition index did correlate with the pearl frequency, while microplastics did not. Mussel health is important to study as they are important actors in the coastal ecosystem, as bioindicators for environmental monitoring, as a food source as well as the recent reports on changes in their distribution across the Norwegian coast

Occurrence of pearls in mussels (Mytilus spp.) from the Norwegian coast

Project manager Inger Lise Nerland BråteMussels (Mytilus spp.) from the Norwegian coast produce pearls, up to as many >360 pearls per individual, and it seems to be a southern-northern gradient with more pearls in mussels from the south than from the north. Out of the 280 mussels studied, nearly 2000 pearls were found, and the mussels producing pearls were all >4 cm. Size and condition index did correlate with the pearl frequency, while microplastics did not. Mussel health is important to study as they are important actors in the coastal ecosystem, as bioindicators for environmental monitoring, as a food source as well as the recent reports on changes in their distribution across the Norwegian coast.Norwegian Environment AgencypublishedVersio

Hydrophobic/Hydrophilic Triblock Copolymers: Synthesis and Properties of Physically Cross-Linked Hydrogels

Hydrophobic/hydrophilic triblock copolymers of poly­(2-(<i>N</i>-ethylperfluorooctane­sulfonamido)­ethylmethyl acrylate) and poly­(<i>N,N</i>′-dimethylacrylamide) (PD) were synthesized by sequential reversible addition–fragmentation chain transfer polymerization. Physically cross-linked hydrogels were produced by immersing compression-molded triblock copolymers into water. The copolymers and their hydrogels were characterized by differential scanning calorimetry, thermogravimetric analysis, thermal desorption-GC/MS analysis, swelling isotherms, wide- and small-angle X-ray scattering, and dynamic mechanical analysis. The equilibrium water sorption of the hydrogels depended on the length of the water-soluble polymer block (PD), and the block copolymers swelled more in water than a random copolymer of the same composition. The block copolymer hydrogels were viscoelastic, though the frequency dependence of the dynamic modulus was weak. The dynamic modulus of the block copolymer hydrogels ranged from ∼10³ to 4 × 10⁴ Pa, which was much lower than the modulus of a random copolymer hydrogel of the same composition

OSPAR-metodikk og plastanalyse av strandsøppel fra Nordre Langåra og Akerøya

Mer strandsøppel ble registrert på Akerøya (fra 2018) fra Ytre Hvaler, enn Nordre Langåra (fra 2019) fra Indre Oslofjord, men det er usikkert om disse tallene er robuste nok til å konkludere med at Akerøya har større plastbelastning enn Nordre Langåra. Mesteparten av avfallet, målt i antall, som ble funnet i både indre og ytre Oslofjord var fiskerirelatert, og mye av dette var såkalte «dollyropes». Den nest mest vanlige kategorien var uidentifiserbare plastbiter som trolig har mange diffuse kilder. Det var polyetylen (PE) og polypropylen (PP) som dominerte på begge strendene. Dette kan skyldes at disse polymertypene er de mest produserte og brukte plasttypene, samt at de som oftest flyter i sjøvann. Mesteparten av søpla fra ytre Hvaler ble antatt å ha norsk opphav, men av det utenlandske avfallet antas det å være bidrag fra 43 land. OSPAR-metodikken er svært verdifull og på nåværende tidspunkt det beste verktøyet vi har for å registrere strandsøppel for å se på mengde og komposisjon av strandsøppel i Nordøst-Atlanteren. Det er likevel flere forbedringspunkter ved OSPAR-metodikken; blant annet foreslås det å inkludere vekt for de ulike kategoriene, samt inter-kalibrere rydding mellom strender for å harmonisere metoden

Freshwater microplastics in Norway: A first look at sediment, biota and historical plankton samples from Lake Mjøsa and Lake Femunden

The Norwegian Environment Agency (Miljødirektoratet) tasked NIVA to investigate the presence of microplastics in one of Norway’s largest freshwater ecosystems, Lake Mjøsa, using monitoring methods which have been recently optimised for the marine environment. Presented here is a baseline description of microplastic distribution in Lake Mjøsa and Lake Femunden, as well as NIVAs recommendations for future monitoring of microplastics in the Norwegian freshwater environment. Microplastics were identified in sediment across all sites in Lake Mjøsa. Core slices from a known volume of sediment are well suited to investigate both geographical and historical distribution of microplastics. Bivalves, such as the duck mussel appear less useful as a test medium but might be useful for comparative analyses against the marine environment. Samples of historical plankton could be a useful way to study temporal changes in a specific area. However, fibres need to be excluded from historical samples as contamination during past sampling campaigns cannot be accounted for. Contamination mitigation measures should be considered in ongoing plankton sampling to facilitate microplastic monitoring in the future. It is not likely that choosing to investigate only one matrix (i.e. just sediments or just plankton samples) will provide a robust assessment of microplastic contamination for a whole ecosystem. A combination of water, sediment and biota samples are recommended. Microplastic monitoring could also be introduced to already established monitoring programs (e.g. Milfersk and/or ØKOSTOR), albeit gradually, to get a better understanding of microplastic distribution both geographically and between different matrixes (such as water, sediment and different biota). Long-term, continuous monitoring will eventually generate a knowledge base for assessing both the fate of microplastics and the effects they may have on organisms

Fate of microplastics in agricultural soils amended with sewage sludge: Is surface water runoff a relevant environmental pathway?

Embargo until November 18, 2023Sewage sludge used as agricultural fertilizer has been identified as an important source of microplastics (MPs) to the environment. However, the fate of MPs added to agricultural soils is largely unknown. This study investigated the fate of MPs in agricultural soils amended with sewage sludge and the role of surface water runoff as a mechanism driving their transfer to aquatic ecosystems. This was assessed using three experimental plots located in a semi-arid area of Central Spain, which were planted with barley. The experimental plots received the following treatments: (1) control or no sludge application; (2) historical sludge application, five years prior to the experiment; and (3) sludge application at the beginning of the experiment. MPs were analyzed in surface water runoff and in different soil layers to investigate transport and infiltration for one year. The sewage sludge used in our experiment contained 5972–7771 MPs/kg dw. Based on this, we estimated that about 16,000 MPs were added to the agricultural plot amended with sludge. As expected, the sludge application significantly increased the MP concentration in soils. The control plot contained low MP concentrations (31–120 MPs kg−1 dw), potentially originating from atmospheric deposition. The plot treated five years prior to the experiment contained 226–412 and 177–235 MPs kg−1 dw at the start and end of the experiment, respectively; while the recently treated plot contained 182–231 and 138–288 MPs kg−1 dw. Our study shows that MP concentrations remain relatively constant in agricultural soils and that the MP infiltration capacity is very low. Surface water runoff had a negligible influence on the export of MPs from agricultural soils, mobilizing only 0.2–0.4% of the MPs added with sludge. We conclude that, in semi-arid regions, agricultural soils can be considered as long-term accumulators of MPs.publishedVersio

Microplastics in Norwegian coastal areas, rivers, lakes and air (MIKRONOR1)

Prosjektleder Bert van BavelThe Norwegian Environment Agency (Miljødirektoratet, NEA) tasked the Norwegian Institute for Water Research (NIVA) to initiate Norway’s National microplastic monitoring program. The program “Microplastics in Norwegian coastal areas, rivers, lakes and air (MIKRONOR)”, was designed to target the multitude of environments in the Norwegian coastal, freshwater and terrestrial ecosystems. The primary aim is to provide information on levels and types of microplastics in aquatic environments as well as in air and build on the baseline data already generated for a number of these environments on previous assignments by NEA. This report contains the first results of coastal sites, open marine waters, lakes, rivers and air including high-volume water samples (freshwater and marine, n=48), Ferrybox samples (marine, n=20), blue mussels (marine, n=71), vertical plankton net samples (marine, n=29) and 24 air samples (precipitation n= 12 and active air sampling n = 12).Norwegian Environment AgencypublishedVersio